| Message ID | 1461333147-11873-2-git-send-email-harald@ccbib.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 04/22/2016 03:52 PM, Harald Geyer wrote: > The hardware has two current sources ISRC0 and ISRC1 to allow measuring > resistors without additional circuitry. This commit makes them available > as regulators. > > Tested on an imx233-olinuxino board. > > Signed-off-by: Harald Geyer <harald@ccbib.org> > --- > The current regulator API doesn't fit this type of device very well: Typically > consumers will want to set a defined current, ie. min_uA == max_uA, but they > can't without help from configuration data, because the valid values aren't > reported by the API for current regulators. I have been thinking about > extending the API, but currently AFAIK no such consumers exist and most > users, like myself, will force the regulator to a defined value in > devicetree anyway. I am tempted to block this patch and ask you to properly split the mxs-lradc driver into MFD with touchscreen and IIO part and only then add the regulator bits. The lradc is becoming a katamari of ad-hoc misplaced functionality. > .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ > drivers/iio/adc/Kconfig | 1 + > drivers/iio/adc/mxs-lradc.c | 152 +++++++++++++++++++++ > 3 files changed, 182 insertions(+) > > diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > index 555fb11..983952c 100644 > --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > @@ -19,6 +19,15 @@ Optional properties: > - fsl,settling: delay between plate switch to next sample. Allowed value is > 1 ... 2047. It counts at 2 kHz and its default is > 10 (= 5 ms) > +- ISRC0: A node describing the regulator of internal current source 0 > +- ISRC1: A node describing the regulator of internal current source 1 > + > +Required properties for the ISRCx sub-nodes: > +- regulator-max-microamp: See standard regulator binding documentation. > + Valid values are from 0 to 300 in steps of 20. > + > +Optional properties for the ISRCx sub-nodes: > +Any standard regulator properties that apply to current regulators. > > Example for i.MX23 SoC: > > @@ -31,6 +40,16 @@ Example for i.MX23 SoC: > fsl,ave-ctrl = <4>; > fsl,ave-delay = <2>; > fsl,settling = <10>; > + > + isrc_lradc0: ISRC0 { > + regulator-max-microamp = <300>; > + }; > + > + isrc_lradc1: ISRC1 { > + regulator-max-microamp = <120>; > + regulator-min-microamp = <120>; > + regulator-always-on; > + }; > }; > > Example for i.MX28 SoC: > @@ -44,4 +63,14 @@ Example for i.MX28 SoC: > fsl,ave-ctrl = <4>; > fsl,ave-delay = <2>; > fsl,settling = <10>; > + > + isrc_lradc0: ISRC0 { > + regulator-max-microamp = <300>; > + }; > + > + isrc_lradc6: ISRC1 { > + regulator-max-microamp = <120>; > + regulator-min-microamp = <120>; > + regulator-always-on; > + }; > }; > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 5937030..1968d1c 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -319,6 +319,7 @@ config MXS_LRADC > tristate "Freescale i.MX23/i.MX28 LRADC" > depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM > depends on INPUT > + depends on REGULATOR > select STMP_DEVICE > select IIO_BUFFER > select IIO_TRIGGERED_BUFFER > diff --git a/drivers/iio/adc/mxs-lradc.c b/drivers/iio/adc/mxs-lradc.c > index 33051b8..f22f339 100644 > --- a/drivers/iio/adc/mxs-lradc.c > +++ b/drivers/iio/adc/mxs-lradc.c > @@ -40,6 +40,10 @@ > #include <linux/iio/triggered_buffer.h> > #include <linux/iio/sysfs.h> > > +#include <linux/regulator/driver.h> > +#include <linux/regulator/machine.h> > +#include <linux/regulator/of_regulator.h> > + > #define DRIVER_NAME "mxs-lradc" > > #define LRADC_MAX_DELAY_CHANS 4 > @@ -261,6 +265,9 @@ struct mxs_lradc { > unsigned over_sample_delay; > /* time in clocks to wait after the plates where switched */ > unsigned settling_delay; > + > + struct regulator_desc isrc0; > + struct regulator_desc isrc1; > }; > > #define LRADC_CTRL0 0x00 > @@ -305,6 +312,11 @@ struct mxs_lradc { > #define LRADC_CTRL2 0x20 > #define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24 > #define LRADC_CTRL2_TEMPSENSE_PWD BIT(15) > +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE1 BIT(9) > +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE0 BIT(8) > +#define LRADC_CTRL2_TEMP_ISRC1_OFFSET 4 > +#define LRADC_CTRL2_TEMP_ISRC0_OFFSET 0 > +#define LRADC_CTRL2_TEMP_ISRC_MASK 0x0f > > #define LRADC_STATUS 0x40 > #define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0) > @@ -1383,6 +1395,109 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = { > .validate_scan_mask = &mxs_lradc_validate_scan_mask, > }; > > +static int mxs_lradc_regulator_is_enabled(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + int reg = readl(lradc->base + LRADC_CTRL2); > + > + if (dev->desc == &lradc->isrc0) > + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE0; > + else if (dev->desc == &lradc->isrc1) > + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE1; > + > + /* This should never happen */ > + return -ENODEV; > +} > + > +#define LRADC_REGVALUE2uA(regval, offset) \ > + (20 * ((regval >> offset) & LRADC_CTRL2_TEMP_ISRC_MASK)) > + > +static int mxs_lradc_regulator_get_current_limit(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + int reg = readl(lradc->base + LRADC_CTRL2); > + > + if (dev->desc == &lradc->isrc0) > + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC0_OFFSET); > + else if (dev->desc == &lradc->isrc1) > + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC1_OFFSET); > + > + /* This should never happen */ > + return -ENODEV; > +} > + > +static int mxs_lradc_regulator_enable(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + > + if (dev->desc == &lradc->isrc0) > + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, > + LRADC_CTRL2); > + else if (dev->desc == &lradc->isrc1) > + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, > + LRADC_CTRL2); > + else > + /* This should never happen */ > + return -ENODEV; > + > + return 0; > +} > + > +static int mxs_lradc_regulator_disable(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + > + if (dev->desc == &lradc->isrc0) > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, > + LRADC_CTRL2); > + else if (dev->desc == &lradc->isrc1) > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, > + LRADC_CTRL2); > + else > + /* This should never happen */ > + return -ENODEV; > + > + return 0; > +} > + > +static int mxs_lradc_regulator_set_current_limit(struct regulator_dev *dev, > + int min_uA, int max_uA) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + int offset, value; > + > + if (dev->desc == &lradc->isrc0) > + offset = LRADC_CTRL2_TEMP_ISRC0_OFFSET; > + else if (dev->desc == &lradc->isrc1) > + offset = LRADC_CTRL2_TEMP_ISRC1_OFFSET; > + else > + /* This should never happen */ > + return -ENODEV; > + > + value = min_uA / 20; > + if (min_uA % 20) > + value++; > + if (value * 20 > max_uA) > + return -EINVAL; > + if (value & ~LRADC_CTRL2_TEMP_ISRC_MASK) > + /* This should never happen */ > + return -EPERM; > + > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_ISRC_MASK << offset, > + LRADC_CTRL2); > + mxs_lradc_reg_set(lradc, value << offset, LRADC_CTRL2); > + > + return 0; > +} > + > +static struct regulator_ops mxs_lradc_regulator_current_ops = { > + .enable = mxs_lradc_regulator_enable, > + .is_enabled = mxs_lradc_regulator_is_enabled, > + .disable = mxs_lradc_regulator_disable, > + .get_current_limit = mxs_lradc_regulator_get_current_limit, > + .set_current_limit = mxs_lradc_regulator_set_current_limit, > +}; > + > /* > * Driver initialization > */ > @@ -1519,6 +1634,10 @@ static void mxs_lradc_hw_stop(struct mxs_lradc *lradc) > > for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++) > mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i)); > + > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0 | > + LRADC_CTRL2_TEMP_SENSOR_IENABLE1, > + LRADC_CTRL2); > } > > static const struct of_device_id mxs_lradc_dt_ids[] = { > @@ -1592,6 +1711,32 @@ static int mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc, > return 0; > } > > +static void mxs_lradc_reg_helper(struct device_node *np, const char *name, > + struct regulator_config *conf, > + struct regulator_desc *desc) > +{ > + struct regulator_dev *ret; > + > + conf->of_node = of_get_child_by_name(np, name); > + if (!conf->of_node) > + return; > + > + desc->name = name; > + desc->owner = THIS_MODULE; > + desc->type = REGULATOR_CURRENT; > + desc->ops = &mxs_lradc_regulator_current_ops; > + > + conf->init_data = of_get_regulator_init_data(conf->dev, conf->of_node, > + desc); > + ret = devm_regulator_register(conf->dev, desc, conf); > + if (IS_ERR(ret)) > + /* Just pretend the regulator isn't there */ > + dev_err(conf->dev, "Failed to register regulator %s: %ld\n", > + desc->name, PTR_ERR(ret)); > + > + of_node_put(conf->of_node); > +} > + > static int mxs_lradc_probe(struct platform_device *pdev) > { > const struct of_device_id *of_id = > @@ -1603,6 +1748,7 @@ static int mxs_lradc_probe(struct platform_device *pdev) > struct mxs_lradc *lradc; > struct iio_dev *iio; > struct resource *iores; > + struct regulator_config regconf; > int ret = 0, touch_ret; > int i, s; > u64 scale_uv; > @@ -1727,6 +1873,12 @@ static int mxs_lradc_probe(struct platform_device *pdev) > goto err_ts; > } > > + /* Setup regulator devices for current source. */ > + regconf.dev = dev; > + regconf.driver_data = lradc; > + mxs_lradc_reg_helper(node, "ISRC0", ®conf, &lradc->isrc0); > + mxs_lradc_reg_helper(node, "ISRC1", ®conf, &lradc->isrc1); > + > return 0; > > err_ts: >
CCing Mark and Liam. I guess I shouldn't rely blindly on get_maintainer.pl ... On 22.04.2016 15:52, Harald Geyer wrote: > The hardware has two current sources ISRC0 and ISRC1 to allow > measuring > resistors without additional circuitry. This commit makes them > available > as regulators. > > Tested on an imx233-olinuxino board. > > Signed-off-by: Harald Geyer <harald@ccbib.org> > --- > The current regulator API doesn't fit this type of device very well: > Typically > consumers will want to set a defined current, ie. min_uA == max_uA, > but they > can't without help from configuration data, because the valid values > aren't > reported by the API for current regulators. I have been thinking > about > extending the API, but currently AFAIK no such consumers exist and > most > users, like myself, will force the regulator to a defined value in > devicetree anyway. > > .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ > drivers/iio/adc/Kconfig | 1 + > drivers/iio/adc/mxs-lradc.c | 152 > +++++++++++++++++++++ > 3 files changed, 182 insertions(+) > > diff --git > a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > index 555fb11..983952c 100644 > --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > @@ -19,6 +19,15 @@ Optional properties: > - fsl,settling: delay between plate switch to next sample. Allowed > value is > 1 ... 2047. It counts at 2 kHz and its default is > 10 (= 5 ms) > +- ISRC0: A node describing the regulator of internal current source > 0 > +- ISRC1: A node describing the regulator of internal current source > 1 > + > +Required properties for the ISRCx sub-nodes: > +- regulator-max-microamp: See standard regulator binding > documentation. > + Valid values are from 0 to 300 in steps of > 20. > + > +Optional properties for the ISRCx sub-nodes: > +Any standard regulator properties that apply to current regulators. > > Example for i.MX23 SoC: > > @@ -31,6 +40,16 @@ Example for i.MX23 SoC: > fsl,ave-ctrl = <4>; > fsl,ave-delay = <2>; > fsl,settling = <10>; > + > + isrc_lradc0: ISRC0 { > + regulator-max-microamp = <300>; > + }; > + > + isrc_lradc1: ISRC1 { > + regulator-max-microamp = <120>; > + regulator-min-microamp = <120>; > + regulator-always-on; > + }; > }; > > Example for i.MX28 SoC: > @@ -44,4 +63,14 @@ Example for i.MX28 SoC: > fsl,ave-ctrl = <4>; > fsl,ave-delay = <2>; > fsl,settling = <10>; > + > + isrc_lradc0: ISRC0 { > + regulator-max-microamp = <300>; > + }; > + > + isrc_lradc6: ISRC1 { > + regulator-max-microamp = <120>; > + regulator-min-microamp = <120>; > + regulator-always-on; > + }; > }; > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 5937030..1968d1c 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -319,6 +319,7 @@ config MXS_LRADC > tristate "Freescale i.MX23/i.MX28 LRADC" > depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM > depends on INPUT > + depends on REGULATOR > select STMP_DEVICE > select IIO_BUFFER > select IIO_TRIGGERED_BUFFER > diff --git a/drivers/iio/adc/mxs-lradc.c > b/drivers/iio/adc/mxs-lradc.c > index 33051b8..f22f339 100644 > --- a/drivers/iio/adc/mxs-lradc.c > +++ b/drivers/iio/adc/mxs-lradc.c > @@ -40,6 +40,10 @@ > #include <linux/iio/triggered_buffer.h> > #include <linux/iio/sysfs.h> > > +#include <linux/regulator/driver.h> > +#include <linux/regulator/machine.h> > +#include <linux/regulator/of_regulator.h> > + > #define DRIVER_NAME "mxs-lradc" > > #define LRADC_MAX_DELAY_CHANS 4 > @@ -261,6 +265,9 @@ struct mxs_lradc { > unsigned over_sample_delay; > /* time in clocks to wait after the plates where switched */ > unsigned settling_delay; > + > + struct regulator_desc isrc0; > + struct regulator_desc isrc1; > }; > > #define LRADC_CTRL0 0x00 > @@ -305,6 +312,11 @@ struct mxs_lradc { > #define LRADC_CTRL2 0x20 > #define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24 > #define LRADC_CTRL2_TEMPSENSE_PWD BIT(15) > +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE1 BIT(9) > +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE0 BIT(8) > +#define LRADC_CTRL2_TEMP_ISRC1_OFFSET 4 > +#define LRADC_CTRL2_TEMP_ISRC0_OFFSET 0 > +#define LRADC_CTRL2_TEMP_ISRC_MASK 0x0f > > #define LRADC_STATUS 0x40 > #define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0) > @@ -1383,6 +1395,109 @@ static const struct iio_buffer_setup_ops > mxs_lradc_buffer_ops = { > .validate_scan_mask = &mxs_lradc_validate_scan_mask, > }; > > +static int mxs_lradc_regulator_is_enabled(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + int reg = readl(lradc->base + LRADC_CTRL2); > + > + if (dev->desc == &lradc->isrc0) > + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE0; > + else if (dev->desc == &lradc->isrc1) > + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE1; > + > + /* This should never happen */ > + return -ENODEV; > +} > + > +#define LRADC_REGVALUE2uA(regval, offset) \ > + (20 * ((regval >> offset) & LRADC_CTRL2_TEMP_ISRC_MASK)) > + > +static int mxs_lradc_regulator_get_current_limit(struct > regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + int reg = readl(lradc->base + LRADC_CTRL2); > + > + if (dev->desc == &lradc->isrc0) > + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC0_OFFSET); > + else if (dev->desc == &lradc->isrc1) > + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC1_OFFSET); > + > + /* This should never happen */ > + return -ENODEV; > +} > + > +static int mxs_lradc_regulator_enable(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + > + if (dev->desc == &lradc->isrc0) > + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, > + LRADC_CTRL2); > + else if (dev->desc == &lradc->isrc1) > + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, > + LRADC_CTRL2); > + else > + /* This should never happen */ > + return -ENODEV; > + > + return 0; > +} > + > +static int mxs_lradc_regulator_disable(struct regulator_dev *dev) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + > + if (dev->desc == &lradc->isrc0) > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, > + LRADC_CTRL2); > + else if (dev->desc == &lradc->isrc1) > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, > + LRADC_CTRL2); > + else > + /* This should never happen */ > + return -ENODEV; > + > + return 0; > +} > + > +static int mxs_lradc_regulator_set_current_limit(struct > regulator_dev *dev, > + int min_uA, int max_uA) > +{ > + struct mxs_lradc *lradc = rdev_get_drvdata(dev); > + int offset, value; > + > + if (dev->desc == &lradc->isrc0) > + offset = LRADC_CTRL2_TEMP_ISRC0_OFFSET; > + else if (dev->desc == &lradc->isrc1) > + offset = LRADC_CTRL2_TEMP_ISRC1_OFFSET; > + else > + /* This should never happen */ > + return -ENODEV; > + > + value = min_uA / 20; > + if (min_uA % 20) > + value++; > + if (value * 20 > max_uA) > + return -EINVAL; > + if (value & ~LRADC_CTRL2_TEMP_ISRC_MASK) > + /* This should never happen */ > + return -EPERM; > + > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_ISRC_MASK << offset, > + LRADC_CTRL2); > + mxs_lradc_reg_set(lradc, value << offset, LRADC_CTRL2); > + > + return 0; > +} > + > +static struct regulator_ops mxs_lradc_regulator_current_ops = { > + .enable = mxs_lradc_regulator_enable, > + .is_enabled = mxs_lradc_regulator_is_enabled, > + .disable = mxs_lradc_regulator_disable, > + .get_current_limit = mxs_lradc_regulator_get_current_limit, > + .set_current_limit = mxs_lradc_regulator_set_current_limit, > +}; > + > /* > * Driver initialization > */ > @@ -1519,6 +1634,10 @@ static void mxs_lradc_hw_stop(struct mxs_lradc > *lradc) > > for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++) > mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i)); > + > + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0 | > + LRADC_CTRL2_TEMP_SENSOR_IENABLE1, > + LRADC_CTRL2); > } > > static const struct of_device_id mxs_lradc_dt_ids[] = { > @@ -1592,6 +1711,32 @@ static int mxs_lradc_probe_touchscreen(struct > mxs_lradc *lradc, > return 0; > } > > +static void mxs_lradc_reg_helper(struct device_node *np, const char > *name, > + struct regulator_config *conf, > + struct regulator_desc *desc) > +{ > + struct regulator_dev *ret; > + > + conf->of_node = of_get_child_by_name(np, name); > + if (!conf->of_node) > + return; > + > + desc->name = name; > + desc->owner = THIS_MODULE; > + desc->type = REGULATOR_CURRENT; > + desc->ops = &mxs_lradc_regulator_current_ops; > + > + conf->init_data = of_get_regulator_init_data(conf->dev, > conf->of_node, > + desc); > + ret = devm_regulator_register(conf->dev, desc, conf); > + if (IS_ERR(ret)) > + /* Just pretend the regulator isn't there */ > + dev_err(conf->dev, "Failed to register regulator %s: %ld\n", > + desc->name, PTR_ERR(ret)); > + > + of_node_put(conf->of_node); > +} > + > static int mxs_lradc_probe(struct platform_device *pdev) > { > const struct of_device_id *of_id = > @@ -1603,6 +1748,7 @@ static int mxs_lradc_probe(struct > platform_device *pdev) > struct mxs_lradc *lradc; > struct iio_dev *iio; > struct resource *iores; > + struct regulator_config regconf; > int ret = 0, touch_ret; > int i, s; > u64 scale_uv; > @@ -1727,6 +1873,12 @@ static int mxs_lradc_probe(struct > platform_device *pdev) > goto err_ts; > } > > + /* Setup regulator devices for current source. */ > + regconf.dev = dev; > + regconf.driver_data = lradc; > + mxs_lradc_reg_helper(node, "ISRC0", ®conf, &lradc->isrc0); > + mxs_lradc_reg_helper(node, "ISRC1", ®conf, &lradc->isrc1); > + > return 0; > > err_ts:
HI On Fri, Apr 22, 2016 at 5:50 PM, Marek Vasut <marex@denx.de> wrote: > On 04/22/2016 03:52 PM, Harald Geyer wrote: >> The hardware has two current sources ISRC0 and ISRC1 to allow measuring >> resistors without additional circuitry. This commit makes them available >> as regulators. >> >> Tested on an imx233-olinuxino board. >> >> Signed-off-by: Harald Geyer <harald@ccbib.org> >> --- >> The current regulator API doesn't fit this type of device very well: Typically >> consumers will want to set a defined current, ie. min_uA == max_uA, but they >> can't without help from configuration data, because the valid values aren't >> reported by the API for current regulators. I have been thinking about >> extending the API, but currently AFAIK no such consumers exist and most >> users, like myself, will force the regulator to a defined value in >> devicetree anyway. > > I am tempted to block this patch and ask you to properly split the > mxs-lradc driver into MFD with touchscreen and IIO part and only then > add the regulator bits. The lradc is becoming a katamari of ad-hoc > misplaced functionality. I almost finished, I already split the driver into MFD, sorry for the delay. Can this wait a little bit? Thanks, Ksenija >> .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ >> drivers/iio/adc/Kconfig | 1 + >> drivers/iio/adc/mxs-lradc.c | 152 +++++++++++++++++++++ >> 3 files changed, 182 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> index 555fb11..983952c 100644 >> --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> @@ -19,6 +19,15 @@ Optional properties: >> - fsl,settling: delay between plate switch to next sample. Allowed value is >> 1 ... 2047. It counts at 2 kHz and its default is >> 10 (= 5 ms) >> +- ISRC0: A node describing the regulator of internal current source 0 >> +- ISRC1: A node describing the regulator of internal current source 1 >> + >> +Required properties for the ISRCx sub-nodes: >> +- regulator-max-microamp: See standard regulator binding documentation. >> + Valid values are from 0 to 300 in steps of 20. >> + >> +Optional properties for the ISRCx sub-nodes: >> +Any standard regulator properties that apply to current regulators. >> >> Example for i.MX23 SoC: >> >> @@ -31,6 +40,16 @@ Example for i.MX23 SoC: >> fsl,ave-ctrl = <4>; >> fsl,ave-delay = <2>; >> fsl,settling = <10>; >> + >> + isrc_lradc0: ISRC0 { >> + regulator-max-microamp = <300>; >> + }; >> + >> + isrc_lradc1: ISRC1 { >> + regulator-max-microamp = <120>; >> + regulator-min-microamp = <120>; >> + regulator-always-on; >> + }; >> }; >> >> Example for i.MX28 SoC: >> @@ -44,4 +63,14 @@ Example for i.MX28 SoC: >> fsl,ave-ctrl = <4>; >> fsl,ave-delay = <2>; >> fsl,settling = <10>; >> + >> + isrc_lradc0: ISRC0 { >> + regulator-max-microamp = <300>; >> + }; >> + >> + isrc_lradc6: ISRC1 { >> + regulator-max-microamp = <120>; >> + regulator-min-microamp = <120>; >> + regulator-always-on; >> + }; >> }; >> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >> index 5937030..1968d1c 100644 >> --- a/drivers/iio/adc/Kconfig >> +++ b/drivers/iio/adc/Kconfig >> @@ -319,6 +319,7 @@ config MXS_LRADC >> tristate "Freescale i.MX23/i.MX28 LRADC" >> depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM >> depends on INPUT >> + depends on REGULATOR >> select STMP_DEVICE >> select IIO_BUFFER >> select IIO_TRIGGERED_BUFFER >> diff --git a/drivers/iio/adc/mxs-lradc.c b/drivers/iio/adc/mxs-lradc.c >> index 33051b8..f22f339 100644 >> --- a/drivers/iio/adc/mxs-lradc.c >> +++ b/drivers/iio/adc/mxs-lradc.c >> @@ -40,6 +40,10 @@ >> #include <linux/iio/triggered_buffer.h> >> #include <linux/iio/sysfs.h> >> >> +#include <linux/regulator/driver.h> >> +#include <linux/regulator/machine.h> >> +#include <linux/regulator/of_regulator.h> >> + >> #define DRIVER_NAME "mxs-lradc" >> >> #define LRADC_MAX_DELAY_CHANS 4 >> @@ -261,6 +265,9 @@ struct mxs_lradc { >> unsigned over_sample_delay; >> /* time in clocks to wait after the plates where switched */ >> unsigned settling_delay; >> + >> + struct regulator_desc isrc0; >> + struct regulator_desc isrc1; >> }; >> >> #define LRADC_CTRL0 0x00 >> @@ -305,6 +312,11 @@ struct mxs_lradc { >> #define LRADC_CTRL2 0x20 >> #define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24 >> #define LRADC_CTRL2_TEMPSENSE_PWD BIT(15) >> +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE1 BIT(9) >> +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE0 BIT(8) >> +#define LRADC_CTRL2_TEMP_ISRC1_OFFSET 4 >> +#define LRADC_CTRL2_TEMP_ISRC0_OFFSET 0 >> +#define LRADC_CTRL2_TEMP_ISRC_MASK 0x0f >> >> #define LRADC_STATUS 0x40 >> #define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0) >> @@ -1383,6 +1395,109 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = { >> .validate_scan_mask = &mxs_lradc_validate_scan_mask, >> }; >> >> +static int mxs_lradc_regulator_is_enabled(struct regulator_dev *dev) >> +{ >> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >> + int reg = readl(lradc->base + LRADC_CTRL2); >> + >> + if (dev->desc == &lradc->isrc0) >> + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE0; >> + else if (dev->desc == &lradc->isrc1) >> + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE1; >> + >> + /* This should never happen */ >> + return -ENODEV; >> +} >> + >> +#define LRADC_REGVALUE2uA(regval, offset) \ >> + (20 * ((regval >> offset) & LRADC_CTRL2_TEMP_ISRC_MASK)) >> + >> +static int mxs_lradc_regulator_get_current_limit(struct regulator_dev *dev) >> +{ >> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >> + int reg = readl(lradc->base + LRADC_CTRL2); >> + >> + if (dev->desc == &lradc->isrc0) >> + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC0_OFFSET); >> + else if (dev->desc == &lradc->isrc1) >> + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC1_OFFSET); >> + >> + /* This should never happen */ >> + return -ENODEV; >> +} >> + >> +static int mxs_lradc_regulator_enable(struct regulator_dev *dev) >> +{ >> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >> + >> + if (dev->desc == &lradc->isrc0) >> + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, >> + LRADC_CTRL2); >> + else if (dev->desc == &lradc->isrc1) >> + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >> + LRADC_CTRL2); >> + else >> + /* This should never happen */ >> + return -ENODEV; >> + >> + return 0; >> +} >> + >> +static int mxs_lradc_regulator_disable(struct regulator_dev *dev) >> +{ >> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >> + >> + if (dev->desc == &lradc->isrc0) >> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, >> + LRADC_CTRL2); >> + else if (dev->desc == &lradc->isrc1) >> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >> + LRADC_CTRL2); >> + else >> + /* This should never happen */ >> + return -ENODEV; >> + >> + return 0; >> +} >> + >> +static int mxs_lradc_regulator_set_current_limit(struct regulator_dev *dev, >> + int min_uA, int max_uA) >> +{ >> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >> + int offset, value; >> + >> + if (dev->desc == &lradc->isrc0) >> + offset = LRADC_CTRL2_TEMP_ISRC0_OFFSET; >> + else if (dev->desc == &lradc->isrc1) >> + offset = LRADC_CTRL2_TEMP_ISRC1_OFFSET; >> + else >> + /* This should never happen */ >> + return -ENODEV; >> + >> + value = min_uA / 20; >> + if (min_uA % 20) >> + value++; >> + if (value * 20 > max_uA) >> + return -EINVAL; >> + if (value & ~LRADC_CTRL2_TEMP_ISRC_MASK) >> + /* This should never happen */ >> + return -EPERM; >> + >> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_ISRC_MASK << offset, >> + LRADC_CTRL2); >> + mxs_lradc_reg_set(lradc, value << offset, LRADC_CTRL2); >> + >> + return 0; >> +} >> + >> +static struct regulator_ops mxs_lradc_regulator_current_ops = { >> + .enable = mxs_lradc_regulator_enable, >> + .is_enabled = mxs_lradc_regulator_is_enabled, >> + .disable = mxs_lradc_regulator_disable, >> + .get_current_limit = mxs_lradc_regulator_get_current_limit, >> + .set_current_limit = mxs_lradc_regulator_set_current_limit, >> +}; >> + >> /* >> * Driver initialization >> */ >> @@ -1519,6 +1634,10 @@ static void mxs_lradc_hw_stop(struct mxs_lradc *lradc) >> >> for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++) >> mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i)); >> + >> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0 | >> + LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >> + LRADC_CTRL2); >> } >> >> static const struct of_device_id mxs_lradc_dt_ids[] = { >> @@ -1592,6 +1711,32 @@ static int mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc, >> return 0; >> } >> >> +static void mxs_lradc_reg_helper(struct device_node *np, const char *name, >> + struct regulator_config *conf, >> + struct regulator_desc *desc) >> +{ >> + struct regulator_dev *ret; >> + >> + conf->of_node = of_get_child_by_name(np, name); >> + if (!conf->of_node) >> + return; >> + >> + desc->name = name; >> + desc->owner = THIS_MODULE; >> + desc->type = REGULATOR_CURRENT; >> + desc->ops = &mxs_lradc_regulator_current_ops; >> + >> + conf->init_data = of_get_regulator_init_data(conf->dev, conf->of_node, >> + desc); >> + ret = devm_regulator_register(conf->dev, desc, conf); >> + if (IS_ERR(ret)) >> + /* Just pretend the regulator isn't there */ >> + dev_err(conf->dev, "Failed to register regulator %s: %ld\n", >> + desc->name, PTR_ERR(ret)); >> + >> + of_node_put(conf->of_node); >> +} >> + >> static int mxs_lradc_probe(struct platform_device *pdev) >> { >> const struct of_device_id *of_id = >> @@ -1603,6 +1748,7 @@ static int mxs_lradc_probe(struct platform_device *pdev) >> struct mxs_lradc *lradc; >> struct iio_dev *iio; >> struct resource *iores; >> + struct regulator_config regconf; >> int ret = 0, touch_ret; >> int i, s; >> u64 scale_uv; >> @@ -1727,6 +1873,12 @@ static int mxs_lradc_probe(struct platform_device *pdev) >> goto err_ts; >> } >> >> + /* Setup regulator devices for current source. */ >> + regconf.dev = dev; >> + regconf.driver_data = lradc; >> + mxs_lradc_reg_helper(node, "ISRC0", ®conf, &lradc->isrc0); >> + mxs_lradc_reg_helper(node, "ISRC1", ®conf, &lradc->isrc1); >> + >> return 0; >> >> err_ts: >> > > > -- > Best regards, > Marek Vasut > -- > To unsubscribe from this list: send the line "unsubscribe linux-iio" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
[CCing Mark and Liam again] On 22.04.2016 19:00, Ksenija Stanojevi? wrote: > On Fri, Apr 22, 2016 at 5:50 PM, Marek Vasut <marex@denx.de> wrote: >> On 04/22/2016 03:52 PM, Harald Geyer wrote: >>> The hardware has two current sources ISRC0 and ISRC1 to allow >>> measuring >>> resistors without additional circuitry. This commit makes them >>> available >>> as regulators. >>> >>> Tested on an imx233-olinuxino board. >>> >>> Signed-off-by: Harald Geyer <harald@ccbib.org> >>> --- >>> The current regulator API doesn't fit this type of device very >>> well: Typically >>> consumers will want to set a defined current, ie. min_uA == max_uA, >>> but they >>> can't without help from configuration data, because the valid >>> values aren't >>> reported by the API for current regulators. I have been thinking >>> about >>> extending the API, but currently AFAIK no such consumers exist and >>> most >>> users, like myself, will force the regulator to a defined value in >>> devicetree anyway. >> >> I am tempted to block this patch and ask you to properly split the >> mxs-lradc driver into MFD with touchscreen and IIO part and only >> then >> add the regulator bits. The lradc is becoming a katamari of ad-hoc >> misplaced functionality. I know. However I'm afraid working this into a proper MFD is above my skills and I don't feel responsible for the status quo either. > I almost finished, I already split the driver into MFD, sorry for the > delay. Wow, looks like I have a lot of luck today. > Can this wait a little bit? Sure. I now have a working kernel for my purposes, so no hurry on my part. CC my when you submit your code or maybe even pick my patch into your series, if you feel like it. Thanks, Harald > Thanks, > Ksenija > >>> .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ >>> drivers/iio/adc/Kconfig | 1 + >>> drivers/iio/adc/mxs-lradc.c | 152 >>> +++++++++++++++++++++ >>> 3 files changed, 182 insertions(+) >>> >>> diff --git >>> a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> index 555fb11..983952c 100644 >>> --- >>> a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> +++ >>> b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> @@ -19,6 +19,15 @@ Optional properties: >>> - fsl,settling: delay between plate switch to next sample. Allowed >>> value is >>> 1 ... 2047. It counts at 2 kHz and its default is >>> 10 (= 5 ms) >>> +- ISRC0: A node describing the regulator of internal current >>> source 0 >>> +- ISRC1: A node describing the regulator of internal current >>> source 1 >>> + >>> +Required properties for the ISRCx sub-nodes: >>> +- regulator-max-microamp: See standard regulator binding >>> documentation. >>> + Valid values are from 0 to 300 in steps >>> of 20. >>> + >>> +Optional properties for the ISRCx sub-nodes: >>> +Any standard regulator properties that apply to current >>> regulators. >>> >>> Example for i.MX23 SoC: >>> >>> @@ -31,6 +40,16 @@ Example for i.MX23 SoC: >>> fsl,ave-ctrl = <4>; >>> fsl,ave-delay = <2>; >>> fsl,settling = <10>; >>> + >>> + isrc_lradc0: ISRC0 { >>> + regulator-max-microamp = <300>; >>> + }; >>> + >>> + isrc_lradc1: ISRC1 { >>> + regulator-max-microamp = <120>; >>> + regulator-min-microamp = <120>; >>> + regulator-always-on; >>> + }; >>> }; >>> >>> Example for i.MX28 SoC: >>> @@ -44,4 +63,14 @@ Example for i.MX28 SoC: >>> fsl,ave-ctrl = <4>; >>> fsl,ave-delay = <2>; >>> fsl,settling = <10>; >>> + >>> + isrc_lradc0: ISRC0 { >>> + regulator-max-microamp = <300>; >>> + }; >>> + >>> + isrc_lradc6: ISRC1 { >>> + regulator-max-microamp = <120>; >>> + regulator-min-microamp = <120>; >>> + regulator-always-on; >>> + }; >>> }; >>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >>> index 5937030..1968d1c 100644 >>> --- a/drivers/iio/adc/Kconfig >>> +++ b/drivers/iio/adc/Kconfig >>> @@ -319,6 +319,7 @@ config MXS_LRADC >>> tristate "Freescale i.MX23/i.MX28 LRADC" >>> depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM >>> depends on INPUT >>> + depends on REGULATOR >>> select STMP_DEVICE >>> select IIO_BUFFER >>> select IIO_TRIGGERED_BUFFER >>> diff --git a/drivers/iio/adc/mxs-lradc.c >>> b/drivers/iio/adc/mxs-lradc.c >>> index 33051b8..f22f339 100644 >>> --- a/drivers/iio/adc/mxs-lradc.c >>> +++ b/drivers/iio/adc/mxs-lradc.c >>> @@ -40,6 +40,10 @@ >>> #include <linux/iio/triggered_buffer.h> >>> #include <linux/iio/sysfs.h> >>> >>> +#include <linux/regulator/driver.h> >>> +#include <linux/regulator/machine.h> >>> +#include <linux/regulator/of_regulator.h> >>> + >>> #define DRIVER_NAME "mxs-lradc" >>> >>> #define LRADC_MAX_DELAY_CHANS 4 >>> @@ -261,6 +265,9 @@ struct mxs_lradc { >>> unsigned over_sample_delay; >>> /* time in clocks to wait after the plates where switched */ >>> unsigned settling_delay; >>> + >>> + struct regulator_desc isrc0; >>> + struct regulator_desc isrc1; >>> }; >>> >>> #define LRADC_CTRL0 0x00 >>> @@ -305,6 +312,11 @@ struct mxs_lradc { >>> #define LRADC_CTRL2 0x20 >>> #define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24 >>> #define LRADC_CTRL2_TEMPSENSE_PWD BIT(15) >>> +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE1 BIT(9) >>> +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE0 BIT(8) >>> +#define LRADC_CTRL2_TEMP_ISRC1_OFFSET 4 >>> +#define LRADC_CTRL2_TEMP_ISRC0_OFFSET 0 >>> +#define LRADC_CTRL2_TEMP_ISRC_MASK 0x0f >>> >>> #define LRADC_STATUS 0x40 >>> #define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0) >>> @@ -1383,6 +1395,109 @@ static const struct iio_buffer_setup_ops >>> mxs_lradc_buffer_ops = { >>> .validate_scan_mask = &mxs_lradc_validate_scan_mask, >>> }; >>> >>> +static int mxs_lradc_regulator_is_enabled(struct regulator_dev >>> *dev) >>> +{ >>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>> + int reg = readl(lradc->base + LRADC_CTRL2); >>> + >>> + if (dev->desc == &lradc->isrc0) >>> + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE0; >>> + else if (dev->desc == &lradc->isrc1) >>> + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE1; >>> + >>> + /* This should never happen */ >>> + return -ENODEV; >>> +} >>> + >>> +#define LRADC_REGVALUE2uA(regval, offset) \ >>> + (20 * ((regval >> offset) & LRADC_CTRL2_TEMP_ISRC_MASK)) >>> + >>> +static int mxs_lradc_regulator_get_current_limit(struct >>> regulator_dev *dev) >>> +{ >>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>> + int reg = readl(lradc->base + LRADC_CTRL2); >>> + >>> + if (dev->desc == &lradc->isrc0) >>> + return LRADC_REGVALUE2uA(reg, >>> LRADC_CTRL2_TEMP_ISRC0_OFFSET); >>> + else if (dev->desc == &lradc->isrc1) >>> + return LRADC_REGVALUE2uA(reg, >>> LRADC_CTRL2_TEMP_ISRC1_OFFSET); >>> + >>> + /* This should never happen */ >>> + return -ENODEV; >>> +} >>> + >>> +static int mxs_lradc_regulator_enable(struct regulator_dev *dev) >>> +{ >>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>> + >>> + if (dev->desc == &lradc->isrc0) >>> + mxs_lradc_reg_set(lradc, >>> LRADC_CTRL2_TEMP_SENSOR_IENABLE0, >>> + LRADC_CTRL2); >>> + else if (dev->desc == &lradc->isrc1) >>> + mxs_lradc_reg_set(lradc, >>> LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >>> + LRADC_CTRL2); >>> + else >>> + /* This should never happen */ >>> + return -ENODEV; >>> + >>> + return 0; >>> +} >>> + >>> +static int mxs_lradc_regulator_disable(struct regulator_dev *dev) >>> +{ >>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>> + >>> + if (dev->desc == &lradc->isrc0) >>> + mxs_lradc_reg_clear(lradc, >>> LRADC_CTRL2_TEMP_SENSOR_IENABLE0, >>> + LRADC_CTRL2); >>> + else if (dev->desc == &lradc->isrc1) >>> + mxs_lradc_reg_clear(lradc, >>> LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >>> + LRADC_CTRL2); >>> + else >>> + /* This should never happen */ >>> + return -ENODEV; >>> + >>> + return 0; >>> +} >>> + >>> +static int mxs_lradc_regulator_set_current_limit(struct >>> regulator_dev *dev, >>> + int min_uA, int >>> max_uA) >>> +{ >>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>> + int offset, value; >>> + >>> + if (dev->desc == &lradc->isrc0) >>> + offset = LRADC_CTRL2_TEMP_ISRC0_OFFSET; >>> + else if (dev->desc == &lradc->isrc1) >>> + offset = LRADC_CTRL2_TEMP_ISRC1_OFFSET; >>> + else >>> + /* This should never happen */ >>> + return -ENODEV; >>> + >>> + value = min_uA / 20; >>> + if (min_uA % 20) >>> + value++; >>> + if (value * 20 > max_uA) >>> + return -EINVAL; >>> + if (value & ~LRADC_CTRL2_TEMP_ISRC_MASK) >>> + /* This should never happen */ >>> + return -EPERM; >>> + >>> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_ISRC_MASK << >>> offset, >>> + LRADC_CTRL2); >>> + mxs_lradc_reg_set(lradc, value << offset, LRADC_CTRL2); >>> + >>> + return 0; >>> +} >>> + >>> +static struct regulator_ops mxs_lradc_regulator_current_ops = { >>> + .enable = mxs_lradc_regulator_enable, >>> + .is_enabled = mxs_lradc_regulator_is_enabled, >>> + .disable = mxs_lradc_regulator_disable, >>> + .get_current_limit = mxs_lradc_regulator_get_current_limit, >>> + .set_current_limit = mxs_lradc_regulator_set_current_limit, >>> +}; >>> + >>> /* >>> * Driver initialization >>> */ >>> @@ -1519,6 +1634,10 @@ static void mxs_lradc_hw_stop(struct >>> mxs_lradc *lradc) >>> >>> for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++) >>> mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i)); >>> + >>> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0 | >>> + >>> LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >>> + LRADC_CTRL2); >>> } >>> >>> static const struct of_device_id mxs_lradc_dt_ids[] = { >>> @@ -1592,6 +1711,32 @@ static int >>> mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc, >>> return 0; >>> } >>> >>> +static void mxs_lradc_reg_helper(struct device_node *np, const >>> char *name, >>> + struct regulator_config *conf, >>> + struct regulator_desc *desc) >>> +{ >>> + struct regulator_dev *ret; >>> + >>> + conf->of_node = of_get_child_by_name(np, name); >>> + if (!conf->of_node) >>> + return; >>> + >>> + desc->name = name; >>> + desc->owner = THIS_MODULE; >>> + desc->type = REGULATOR_CURRENT; >>> + desc->ops = &mxs_lradc_regulator_current_ops; >>> + >>> + conf->init_data = of_get_regulator_init_data(conf->dev, >>> conf->of_node, >>> + desc); >>> + ret = devm_regulator_register(conf->dev, desc, conf); >>> + if (IS_ERR(ret)) >>> + /* Just pretend the regulator isn't there */ >>> + dev_err(conf->dev, "Failed to register regulator %s: >>> %ld\n", >>> + desc->name, PTR_ERR(ret)); >>> + >>> + of_node_put(conf->of_node); >>> +} >>> + >>> static int mxs_lradc_probe(struct platform_device *pdev) >>> { >>> const struct of_device_id *of_id = >>> @@ -1603,6 +1748,7 @@ static int mxs_lradc_probe(struct >>> platform_device *pdev) >>> struct mxs_lradc *lradc; >>> struct iio_dev *iio; >>> struct resource *iores; >>> + struct regulator_config regconf; >>> int ret = 0, touch_ret; >>> int i, s; >>> u64 scale_uv; >>> @@ -1727,6 +1873,12 @@ static int mxs_lradc_probe(struct >>> platform_device *pdev) >>> goto err_ts; >>> } >>> >>> + /* Setup regulator devices for current source. */ >>> + regconf.dev = dev; >>> + regconf.driver_data = lradc; >>> + mxs_lradc_reg_helper(node, "ISRC0", ®conf, &lradc->isrc0); >>> + mxs_lradc_reg_helper(node, "ISRC1", ®conf, &lradc->isrc1); >>> + >>> return 0; >>> >>> err_ts: >>> >> >> >> -- >> Best regards, >> Marek Vasut >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-iio" >> in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html
On 22/04/16 20:23, Harald Geyer wrote: > [CCing Mark and Liam again] > > On 22.04.2016 19:00, Ksenija Stanojevi? wrote: >> On Fri, Apr 22, 2016 at 5:50 PM, Marek Vasut <marex@denx.de> wrote: >>> On 04/22/2016 03:52 PM, Harald Geyer wrote: >>>> The hardware has two current sources ISRC0 and ISRC1 to allow measuring >>>> resistors without additional circuitry. This commit makes them available >>>> as regulators. >>>> >>>> Tested on an imx233-olinuxino board. >>>> >>>> Signed-off-by: Harald Geyer <harald@ccbib.org> >>>> --- >>>> The current regulator API doesn't fit this type of device very well: Typically >>>> consumers will want to set a defined current, ie. min_uA == max_uA, but they >>>> can't without help from configuration data, because the valid values aren't >>>> reported by the API for current regulators. I have been thinking about >>>> extending the API, but currently AFAIK no such consumers exist and most >>>> users, like myself, will force the regulator to a defined value in >>>> devicetree anyway. >>> >>> I am tempted to block this patch and ask you to properly split the >>> mxs-lradc driver into MFD with touchscreen and IIO part and only then >>> add the regulator bits. The lradc is becoming a katamari of ad-hoc >>> misplaced functionality. > > I know. However I'm afraid working this into a proper MFD is above my skills > and I don't feel responsible for the status quo either. > >> I almost finished, I already split the driver into MFD, sorry for the delay. > > Wow, looks like I have a lot of luck today. Indeed! Glad to here you have this underway Ksenija. Let me know if you want any other patches held until this is done. For now I'm assuming that Stefan's series won't cause too much trouble, so I'll probably apply those, but will hold anything more major until your patches show up. Thanks, Jonathan > >> Can this wait a little bit? > > Sure. I now have a working kernel for my purposes, so no hurry on my part. > CC my when you submit your code or maybe even pick my patch into your series, > if you feel like it. > > Thanks, > Harald > >> Thanks, >> Ksenija >> >>>> .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ >>>> drivers/iio/adc/Kconfig | 1 + >>>> drivers/iio/adc/mxs-lradc.c | 152 +++++++++++++++++++++ >>>> 3 files changed, 182 insertions(+) >>>> >>>> diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> index 555fb11..983952c 100644 >>>> --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> @@ -19,6 +19,15 @@ Optional properties: >>>> - fsl,settling: delay between plate switch to next sample. Allowed value is >>>> 1 ... 2047. It counts at 2 kHz and its default is >>>> 10 (= 5 ms) >>>> +- ISRC0: A node describing the regulator of internal current source 0 >>>> +- ISRC1: A node describing the regulator of internal current source 1 >>>> + >>>> +Required properties for the ISRCx sub-nodes: >>>> +- regulator-max-microamp: See standard regulator binding documentation. >>>> + Valid values are from 0 to 300 in steps of 20. >>>> + >>>> +Optional properties for the ISRCx sub-nodes: >>>> +Any standard regulator properties that apply to current regulators. >>>> >>>> Example for i.MX23 SoC: >>>> >>>> @@ -31,6 +40,16 @@ Example for i.MX23 SoC: >>>> fsl,ave-ctrl = <4>; >>>> fsl,ave-delay = <2>; >>>> fsl,settling = <10>; >>>> + >>>> + isrc_lradc0: ISRC0 { >>>> + regulator-max-microamp = <300>; >>>> + }; >>>> + >>>> + isrc_lradc1: ISRC1 { >>>> + regulator-max-microamp = <120>; >>>> + regulator-min-microamp = <120>; >>>> + regulator-always-on; >>>> + }; >>>> }; >>>> >>>> Example for i.MX28 SoC: >>>> @@ -44,4 +63,14 @@ Example for i.MX28 SoC: >>>> fsl,ave-ctrl = <4>; >>>> fsl,ave-delay = <2>; >>>> fsl,settling = <10>; >>>> + >>>> + isrc_lradc0: ISRC0 { >>>> + regulator-max-microamp = <300>; >>>> + }; >>>> + >>>> + isrc_lradc6: ISRC1 { >>>> + regulator-max-microamp = <120>; >>>> + regulator-min-microamp = <120>; >>>> + regulator-always-on; >>>> + }; >>>> }; >>>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >>>> index 5937030..1968d1c 100644 >>>> --- a/drivers/iio/adc/Kconfig >>>> +++ b/drivers/iio/adc/Kconfig >>>> @@ -319,6 +319,7 @@ config MXS_LRADC >>>> tristate "Freescale i.MX23/i.MX28 LRADC" >>>> depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM >>>> depends on INPUT >>>> + depends on REGULATOR >>>> select STMP_DEVICE >>>> select IIO_BUFFER >>>> select IIO_TRIGGERED_BUFFER >>>> diff --git a/drivers/iio/adc/mxs-lradc.c b/drivers/iio/adc/mxs-lradc.c >>>> index 33051b8..f22f339 100644 >>>> --- a/drivers/iio/adc/mxs-lradc.c >>>> +++ b/drivers/iio/adc/mxs-lradc.c >>>> @@ -40,6 +40,10 @@ >>>> #include <linux/iio/triggered_buffer.h> >>>> #include <linux/iio/sysfs.h> >>>> >>>> +#include <linux/regulator/driver.h> >>>> +#include <linux/regulator/machine.h> >>>> +#include <linux/regulator/of_regulator.h> >>>> + >>>> #define DRIVER_NAME "mxs-lradc" >>>> >>>> #define LRADC_MAX_DELAY_CHANS 4 >>>> @@ -261,6 +265,9 @@ struct mxs_lradc { >>>> unsigned over_sample_delay; >>>> /* time in clocks to wait after the plates where switched */ >>>> unsigned settling_delay; >>>> + >>>> + struct regulator_desc isrc0; >>>> + struct regulator_desc isrc1; >>>> }; >>>> >>>> #define LRADC_CTRL0 0x00 >>>> @@ -305,6 +312,11 @@ struct mxs_lradc { >>>> #define LRADC_CTRL2 0x20 >>>> #define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24 >>>> #define LRADC_CTRL2_TEMPSENSE_PWD BIT(15) >>>> +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE1 BIT(9) >>>> +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE0 BIT(8) >>>> +#define LRADC_CTRL2_TEMP_ISRC1_OFFSET 4 >>>> +#define LRADC_CTRL2_TEMP_ISRC0_OFFSET 0 >>>> +#define LRADC_CTRL2_TEMP_ISRC_MASK 0x0f >>>> >>>> #define LRADC_STATUS 0x40 >>>> #define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0) >>>> @@ -1383,6 +1395,109 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = { >>>> .validate_scan_mask = &mxs_lradc_validate_scan_mask, >>>> }; >>>> >>>> +static int mxs_lradc_regulator_is_enabled(struct regulator_dev *dev) >>>> +{ >>>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>>> + int reg = readl(lradc->base + LRADC_CTRL2); >>>> + >>>> + if (dev->desc == &lradc->isrc0) >>>> + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE0; >>>> + else if (dev->desc == &lradc->isrc1) >>>> + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE1; >>>> + >>>> + /* This should never happen */ >>>> + return -ENODEV; >>>> +} >>>> + >>>> +#define LRADC_REGVALUE2uA(regval, offset) \ >>>> + (20 * ((regval >> offset) & LRADC_CTRL2_TEMP_ISRC_MASK)) >>>> + >>>> +static int mxs_lradc_regulator_get_current_limit(struct regulator_dev *dev) >>>> +{ >>>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>>> + int reg = readl(lradc->base + LRADC_CTRL2); >>>> + >>>> + if (dev->desc == &lradc->isrc0) >>>> + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC0_OFFSET); >>>> + else if (dev->desc == &lradc->isrc1) >>>> + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC1_OFFSET); >>>> + >>>> + /* This should never happen */ >>>> + return -ENODEV; >>>> +} >>>> + >>>> +static int mxs_lradc_regulator_enable(struct regulator_dev *dev) >>>> +{ >>>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>>> + >>>> + if (dev->desc == &lradc->isrc0) >>>> + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, >>>> + LRADC_CTRL2); >>>> + else if (dev->desc == &lradc->isrc1) >>>> + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >>>> + LRADC_CTRL2); >>>> + else >>>> + /* This should never happen */ >>>> + return -ENODEV; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int mxs_lradc_regulator_disable(struct regulator_dev *dev) >>>> +{ >>>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>>> + >>>> + if (dev->desc == &lradc->isrc0) >>>> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, >>>> + LRADC_CTRL2); >>>> + else if (dev->desc == &lradc->isrc1) >>>> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >>>> + LRADC_CTRL2); >>>> + else >>>> + /* This should never happen */ >>>> + return -ENODEV; >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static int mxs_lradc_regulator_set_current_limit(struct regulator_dev *dev, >>>> + int min_uA, int max_uA) >>>> +{ >>>> + struct mxs_lradc *lradc = rdev_get_drvdata(dev); >>>> + int offset, value; >>>> + >>>> + if (dev->desc == &lradc->isrc0) >>>> + offset = LRADC_CTRL2_TEMP_ISRC0_OFFSET; >>>> + else if (dev->desc == &lradc->isrc1) >>>> + offset = LRADC_CTRL2_TEMP_ISRC1_OFFSET; >>>> + else >>>> + /* This should never happen */ >>>> + return -ENODEV; >>>> + >>>> + value = min_uA / 20; >>>> + if (min_uA % 20) >>>> + value++; >>>> + if (value * 20 > max_uA) >>>> + return -EINVAL; >>>> + if (value & ~LRADC_CTRL2_TEMP_ISRC_MASK) >>>> + /* This should never happen */ >>>> + return -EPERM; >>>> + >>>> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_ISRC_MASK << offset, >>>> + LRADC_CTRL2); >>>> + mxs_lradc_reg_set(lradc, value << offset, LRADC_CTRL2); >>>> + >>>> + return 0; >>>> +} >>>> + >>>> +static struct regulator_ops mxs_lradc_regulator_current_ops = { >>>> + .enable = mxs_lradc_regulator_enable, >>>> + .is_enabled = mxs_lradc_regulator_is_enabled, >>>> + .disable = mxs_lradc_regulator_disable, >>>> + .get_current_limit = mxs_lradc_regulator_get_current_limit, >>>> + .set_current_limit = mxs_lradc_regulator_set_current_limit, >>>> +}; >>>> + >>>> /* >>>> * Driver initialization >>>> */ >>>> @@ -1519,6 +1634,10 @@ static void mxs_lradc_hw_stop(struct mxs_lradc *lradc) >>>> >>>> for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++) >>>> mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i)); >>>> + >>>> + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0 | >>>> + LRADC_CTRL2_TEMP_SENSOR_IENABLE1, >>>> + LRADC_CTRL2); >>>> } >>>> >>>> static const struct of_device_id mxs_lradc_dt_ids[] = { >>>> @@ -1592,6 +1711,32 @@ static int mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc, >>>> return 0; >>>> } >>>> >>>> +static void mxs_lradc_reg_helper(struct device_node *np, const char *name, >>>> + struct regulator_config *conf, >>>> + struct regulator_desc *desc) >>>> +{ >>>> + struct regulator_dev *ret; >>>> + >>>> + conf->of_node = of_get_child_by_name(np, name); >>>> + if (!conf->of_node) >>>> + return; >>>> + >>>> + desc->name = name; >>>> + desc->owner = THIS_MODULE; >>>> + desc->type = REGULATOR_CURRENT; >>>> + desc->ops = &mxs_lradc_regulator_current_ops; >>>> + >>>> + conf->init_data = of_get_regulator_init_data(conf->dev, conf->of_node, >>>> + desc); >>>> + ret = devm_regulator_register(conf->dev, desc, conf); >>>> + if (IS_ERR(ret)) >>>> + /* Just pretend the regulator isn't there */ >>>> + dev_err(conf->dev, "Failed to register regulator %s: %ld\n", >>>> + desc->name, PTR_ERR(ret)); >>>> + >>>> + of_node_put(conf->of_node); >>>> +} >>>> + >>>> static int mxs_lradc_probe(struct platform_device *pdev) >>>> { >>>> const struct of_device_id *of_id = >>>> @@ -1603,6 +1748,7 @@ static int mxs_lradc_probe(struct platform_device *pdev) >>>> struct mxs_lradc *lradc; >>>> struct iio_dev *iio; >>>> struct resource *iores; >>>> + struct regulator_config regconf; >>>> int ret = 0, touch_ret; >>>> int i, s; >>>> u64 scale_uv; >>>> @@ -1727,6 +1873,12 @@ static int mxs_lradc_probe(struct platform_device *pdev) >>>> goto err_ts; >>>> } >>>> >>>> + /* Setup regulator devices for current source. */ >>>> + regconf.dev = dev; >>>> + regconf.driver_data = lradc; >>>> + mxs_lradc_reg_helper(node, "ISRC0", ®conf, &lradc->isrc0); >>>> + mxs_lradc_reg_helper(node, "ISRC1", ®conf, &lradc->isrc1); >>>> + >>>> return 0; >>>> >>>> err_ts: >>>> >>> >>> >>> -- >>> Best regards, >>> Marek Vasut >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-iio" in >>> the body of a message to majordomo@vger.kernel.org >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >
Hi Harald, Am 22.04.2016 um 15:52 schrieb Harald Geyer: > The hardware has two current sources ISRC0 and ISRC1 to allow measuring > resistors without additional circuitry. This commit makes them available > as regulators. > > Tested on an imx233-olinuxino board. > > Signed-off-by: Harald Geyer <harald@ccbib.org> > --- > The current regulator API doesn't fit this type of device very well: Typically > consumers will want to set a defined current, ie. min_uA == max_uA, but they > can't without help from configuration data, because the valid values aren't > reported by the API for current regulators. I have been thinking about > extending the API, but currently AFAIK no such consumers exist and most > users, like myself, will force the regulator to a defined value in > devicetree anyway. > > .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ > drivers/iio/adc/Kconfig | 1 + > drivers/iio/adc/mxs-lradc.c | 152 +++++++++++++++++++++ > 3 files changed, 182 insertions(+) > > diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > index 555fb11..983952c 100644 > --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt > @@ -19,6 +19,15 @@ Optional properties: > - fsl,settling: delay between plate switch to next sample. Allowed value is > 1 ... 2047. It counts at 2 kHz and its default is > 10 (= 5 ms) > +- ISRC0: A node describing the regulator of internal current source 0 > +- ISRC1: A node describing the regulator of internal current source 1 > + > +Required properties for the ISRCx sub-nodes: > +- regulator-max-microamp: See standard regulator binding documentation. > + Valid values are from 0 to 300 in steps of 20. > + > +Optional properties for the ISRCx sub-nodes: > +Any standard regulator properties that apply to current regulators. > > Example for i.MX23 SoC: > > @@ -31,6 +40,16 @@ Example for i.MX23 SoC: > fsl,ave-ctrl = <4>; > fsl,ave-delay = <2>; > fsl,settling = <10>; > + > + isrc_lradc0: ISRC0 { > + regulator-max-microamp = <300>; > + }; > + > + isrc_lradc1: ISRC1 { > + regulator-max-microamp = <120>; > + regulator-min-microamp = <120>; > + regulator-always-on; > + }; IMHO the binding should represent the direct connection between the current source and the physical channel. I think a node label isn't enough. Unfortunately i don't have an idea to do it the "right way". > }; > > Example for i.MX28 SoC: > @@ -44,4 +63,14 @@ Example for i.MX28 SoC: > fsl,ave-ctrl = <4>; > fsl,ave-delay = <2>; > fsl,settling = <10>; > + > + isrc_lradc0: ISRC0 { > + regulator-max-microamp = <300>; > + }; > + > + isrc_lradc6: ISRC1 { > + regulator-max-microamp = <120>; > + regulator-min-microamp = <120>; > + regulator-always-on; > + }; > }; > diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig > index 5937030..1968d1c 100644 > --- a/drivers/iio/adc/Kconfig > +++ b/drivers/iio/adc/Kconfig > @@ -319,6 +319,7 @@ config MXS_LRADC > tristate "Freescale i.MX23/i.MX28 LRADC" > depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM > depends on INPUT > + depends on REGULATOR Any chance to avoid this dependency for an optional feature? Stefan > select STMP_DEVICE > select IIO_BUFFER > select IIO_TRIGGERED_BUFFER
Hi Stefan! On 03.05.2016 13:07, Stefan Wahren wrote: > Am 22.04.2016 um 15:52 schrieb Harald Geyer: >> The hardware has two current sources ISRC0 and ISRC1 to allow >> measuring >> resistors without additional circuitry. This commit makes them >> available >> as regulators. >> >> Tested on an imx233-olinuxino board. >> >> Signed-off-by: Harald Geyer <harald@ccbib.org> >> --- >> The current regulator API doesn't fit this type of device very well: >> Typically >> consumers will want to set a defined current, ie. min_uA == max_uA, >> but they >> can't without help from configuration data, because the valid values >> aren't >> reported by the API for current regulators. I have been thinking >> about >> extending the API, but currently AFAIK no such consumers exist and >> most >> users, like myself, will force the regulator to a defined value in >> devicetree anyway. >> >> .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ >> drivers/iio/adc/Kconfig | 1 + >> drivers/iio/adc/mxs-lradc.c | 152 >> +++++++++++++++++++++ >> 3 files changed, 182 insertions(+) >> >> diff --git >> a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> index 555fb11..983952c 100644 >> --- >> a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> +++ >> b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >> @@ -19,6 +19,15 @@ Optional properties: >> - fsl,settling: delay between plate switch to next sample. Allowed >> value is >> 1 ... 2047. It counts at 2 kHz and its default is >> 10 (= 5 ms) >> +- ISRC0: A node describing the regulator of internal current source >> 0 >> +- ISRC1: A node describing the regulator of internal current source >> 1 >> + >> +Required properties for the ISRCx sub-nodes: >> +- regulator-max-microamp: See standard regulator binding >> documentation. >> + Valid values are from 0 to 300 in steps >> of 20. >> + >> +Optional properties for the ISRCx sub-nodes: >> +Any standard regulator properties that apply to current regulators. >> >> Example for i.MX23 SoC: >> >> @@ -31,6 +40,16 @@ Example for i.MX23 SoC: >> fsl,ave-ctrl = <4>; >> fsl,ave-delay = <2>; >> fsl,settling = <10>; >> + >> + isrc_lradc0: ISRC0 { >> + regulator-max-microamp = <300>; >> + }; >> + >> + isrc_lradc1: ISRC1 { >> + regulator-max-microamp = <120>; >> + regulator-min-microamp = <120>; >> + regulator-always-on; >> + }; > > IMHO the binding should represent the direct connection between the > current source and the physical channel. I think a node label isn't > enough. Unfortunately i don't have an idea to do it the "right way". I strictly followed the names of the data sheet here: imx23 and imx28 reference manuals both call the current sources ISRC0 and ISRC1 even if they are attached to different channels of the ADC. I think inventing some ISRC6 for imx28 would do more harm then good. >> }; >> >> Example for i.MX28 SoC: >> @@ -44,4 +63,14 @@ Example for i.MX28 SoC: >> fsl,ave-ctrl = <4>; >> fsl,ave-delay = <2>; >> fsl,settling = <10>; >> + >> + isrc_lradc0: ISRC0 { >> + regulator-max-microamp = <300>; >> + }; >> + >> + isrc_lradc6: ISRC1 { >> + regulator-max-microamp = <120>; >> + regulator-min-microamp = <120>; >> + regulator-always-on; >> + }; >> }; >> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >> index 5937030..1968d1c 100644 >> --- a/drivers/iio/adc/Kconfig >> +++ b/drivers/iio/adc/Kconfig >> @@ -319,6 +319,7 @@ config MXS_LRADC >> tristate "Freescale i.MX23/i.MX28 LRADC" >> depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM >> depends on INPUT >> + depends on REGULATOR > > Any chance to avoid this dependency for an optional feature? I haven't looked into it yet, but I expect that that the mfd conversion will avoid this neatly. Thanks, Harald > Stefan > >> select STMP_DEVICE >> select IIO_BUFFER >> select IIO_TRIGGERED_BUFFER
On 03/05/16 12:22, Harald Geyer wrote: > Hi Stefan! > > On 03.05.2016 13:07, Stefan Wahren wrote: >> Am 22.04.2016 um 15:52 schrieb Harald Geyer: >>> The hardware has two current sources ISRC0 and ISRC1 to allow measuring >>> resistors without additional circuitry. This commit makes them available >>> as regulators. >>> >>> Tested on an imx233-olinuxino board. >>> >>> Signed-off-by: Harald Geyer <harald@ccbib.org> >>> --- >>> The current regulator API doesn't fit this type of device very well: Typically >>> consumers will want to set a defined current, ie. min_uA == max_uA, but they >>> can't without help from configuration data, because the valid values aren't >>> reported by the API for current regulators. I have been thinking about >>> extending the API, but currently AFAIK no such consumers exist and most >>> users, like myself, will force the regulator to a defined value in >>> devicetree anyway. >>> >>> .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ >>> drivers/iio/adc/Kconfig | 1 + >>> drivers/iio/adc/mxs-lradc.c | 152 +++++++++++++++++++++ >>> 3 files changed, 182 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> index 555fb11..983952c 100644 >>> --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>> @@ -19,6 +19,15 @@ Optional properties: >>> - fsl,settling: delay between plate switch to next sample. Allowed value is >>> 1 ... 2047. It counts at 2 kHz and its default is >>> 10 (= 5 ms) >>> +- ISRC0: A node describing the regulator of internal current source 0 >>> +- ISRC1: A node describing the regulator of internal current source 1 >>> + >>> +Required properties for the ISRCx sub-nodes: >>> +- regulator-max-microamp: See standard regulator binding documentation. >>> + Valid values are from 0 to 300 in steps of 20. >>> + >>> +Optional properties for the ISRCx sub-nodes: >>> +Any standard regulator properties that apply to current regulators. >>> >>> Example for i.MX23 SoC: >>> >>> @@ -31,6 +40,16 @@ Example for i.MX23 SoC: >>> fsl,ave-ctrl = <4>; >>> fsl,ave-delay = <2>; >>> fsl,settling = <10>; >>> + >>> + isrc_lradc0: ISRC0 { >>> + regulator-max-microamp = <300>; >>> + }; >>> + >>> + isrc_lradc1: ISRC1 { >>> + regulator-max-microamp = <120>; >>> + regulator-min-microamp = <120>; >>> + regulator-always-on; >>> + }; >> >> IMHO the binding should represent the direct connection between the >> current source and the physical channel. I think a node label isn't >> enough. Unfortunately i don't have an idea to do it the "right way". > > I strictly followed the names of the data sheet here: imx23 and imx28 > reference manuals both call the current sources ISRC0 and ISRC1 even > if they are attached to different channels of the ADC. I think > inventing some ISRC6 for imx28 would do more harm then good. So just to check... These two current sources are effectively pushing current out of the ADC input pin? Assumption being that this causes an appropriate voltage across a component between there and 0V? I wonder if we are better off not treating these as regulators at all - whilst you could in theory use them for general purposes, it would be a bit nuts and sometimes the 'it is nuts argument' is enough to mean we don't support something :) I wouldn't have any problem with an additional attribute for the adc channels - maybe something like... in_voltage6_sourcecurrent? Then the control could be pushed to userspace. Or if it only makes sense to do it as a fixed value in DT then define optional child nodes for the individual channels, with the relevant ones have current-source-microamp or something like that as an parameter. What do you think? Jonathan > >>> }; >>> >>> Example for i.MX28 SoC: >>> @@ -44,4 +63,14 @@ Example for i.MX28 SoC: >>> fsl,ave-ctrl = <4>; >>> fsl,ave-delay = <2>; >>> fsl,settling = <10>; >>> + >>> + isrc_lradc0: ISRC0 { >>> + regulator-max-microamp = <300>; >>> + }; >>> + >>> + isrc_lradc6: ISRC1 { >>> + regulator-max-microamp = <120>; >>> + regulator-min-microamp = <120>; >>> + regulator-always-on; >>> + }; >>> }; >>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >>> index 5937030..1968d1c 100644 >>> --- a/drivers/iio/adc/Kconfig >>> +++ b/drivers/iio/adc/Kconfig >>> @@ -319,6 +319,7 @@ config MXS_LRADC >>> tristate "Freescale i.MX23/i.MX28 LRADC" >>> depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM >>> depends on INPUT >>> + depends on REGULATOR >> >> Any chance to avoid this dependency for an optional feature? > > I haven't looked into it yet, but I expect that that the mfd > conversion will avoid this neatly. > > Thanks, > Harald > >> Stefan >> >>> select STMP_DEVICE >>> select IIO_BUFFER >>> select IIO_TRIGGERED_BUFFER >
On 04.05.2016 09:15, Jonathan Cameron wrote: > On 03/05/16 12:22, Harald Geyer wrote: >> On 03.05.2016 13:07, Stefan Wahren wrote: >>> Am 22.04.2016 um 15:52 schrieb Harald Geyer: >>>> The hardware has two current sources ISRC0 and ISRC1 to allow >>>> measuring >>>> resistors without additional circuitry. This commit makes them >>>> available >>>> as regulators. >>>> >>>> Tested on an imx233-olinuxino board. >>>> >>>> Signed-off-by: Harald Geyer <harald@ccbib.org> >>>> --- >>>> The current regulator API doesn't fit this type of device very >>>> well: Typically >>>> consumers will want to set a defined current, ie. min_uA == >>>> max_uA, but they >>>> can't without help from configuration data, because the valid >>>> values aren't >>>> reported by the API for current regulators. I have been thinking >>>> about >>>> extending the API, but currently AFAIK no such consumers exist and >>>> most >>>> users, like myself, will force the regulator to a defined value in >>>> devicetree anyway. >>>> >>>> .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ >>>> drivers/iio/adc/Kconfig | 1 + >>>> drivers/iio/adc/mxs-lradc.c | 152 >>>> +++++++++++++++++++++ >>>> 3 files changed, 182 insertions(+) >>>> >>>> diff --git >>>> a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> index 555fb11..983952c 100644 >>>> --- >>>> a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> +++ >>>> b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt >>>> @@ -19,6 +19,15 @@ Optional properties: >>>> - fsl,settling: delay between plate switch to next sample. >>>> Allowed value is >>>> 1 ... 2047. It counts at 2 kHz and its default is >>>> 10 (= 5 ms) >>>> +- ISRC0: A node describing the regulator of internal current >>>> source 0 >>>> +- ISRC1: A node describing the regulator of internal current >>>> source 1 >>>> + >>>> +Required properties for the ISRCx sub-nodes: >>>> +- regulator-max-microamp: See standard regulator binding >>>> documentation. >>>> + Valid values are from 0 to 300 in steps >>>> of 20. >>>> + >>>> +Optional properties for the ISRCx sub-nodes: >>>> +Any standard regulator properties that apply to current >>>> regulators. >>>> >>>> Example for i.MX23 SoC: >>>> >>>> @@ -31,6 +40,16 @@ Example for i.MX23 SoC: >>>> fsl,ave-ctrl = <4>; >>>> fsl,ave-delay = <2>; >>>> fsl,settling = <10>; >>>> + >>>> + isrc_lradc0: ISRC0 { >>>> + regulator-max-microamp = <300>; >>>> + }; >>>> + >>>> + isrc_lradc1: ISRC1 { >>>> + regulator-max-microamp = <120>; >>>> + regulator-min-microamp = <120>; >>>> + regulator-always-on; >>>> + }; >>> >>> IMHO the binding should represent the direct connection between the >>> current source and the physical channel. I think a node label isn't >>> enough. Unfortunately i don't have an idea to do it the "right >>> way". >> >> I strictly followed the names of the data sheet here: imx23 and >> imx28 >> reference manuals both call the current sources ISRC0 and ISRC1 even >> if they are attached to different channels of the ADC. I think >> inventing some ISRC6 for imx28 would do more harm then good. > So just to check... These two current sources are effectively > pushing current out of the ADC input pin? Assumption being that > this causes an appropriate voltage across a component between there > and 0V? Exactly. > I wonder if we are better off not treating these as regulators at > all - whilst you could in theory use them for general purposes, it > would be a bit nuts and sometimes the 'it is nuts argument' is > enough to mean we don't support something :) Yeah, it would be some funny 4-bit DAC ... > I wouldn't have any problem with an additional attribute for the > adc channels - maybe something like... > > in_voltage6_sourcecurrent? Then the control could be pushed to > userspace. I'm very open to that idea. Not having yet an other subsystem involved would simplify some things a lot. > Or if it only makes sense to do it as a fixed value in DT then > define optional child nodes for the individual channels, with > the relevant ones have current-source-microamp or > something like that as an parameter. My research in thermistors is still ongoing (so I don't have a kernel driver yet) but I think for thermistors with exponential temperature dependence dynamic setting of the current source will be necessary to get high resolution across the whole temperature range. Of course many applications wont need this. For checks like "Is my battery over-heating?" a simple fixed current from DT will to well, so I guess we should support both. > What do you think? As I already stated in an other subthread, I'm not entirely happy with the regulator approach. Having everything inside iio would make supporting complex use cases easier in the future, I guess. Also IIO devices are much easier to control from user space then regulators, which might be desired for this type of device. OTOH I'm not sure how many other devices out there have a similar feature. I'd rather not invent a new API for just very few devices. IMO iio already suffers from the complexity of the sysfs API. Maybe somebody with a good overview of ADCs available on the market can provide some input here. Also of course there are lots of ADCs out there without internal current source and those could be used with thermistors too but would need a regulator anyway. So maybe eventually we would end up with both solutions supported, which I'd avoid if at all possible. (I guess we could work around the last issue by providing some generic driver to pull an iio channel and a regulator together - do we like that level of abstraction?) If we start our own API to control current sources we might end up pretty much reimplementing the regulator API for the single consumer case. I'd like to have input from more people on the above points before going one way or the other. Thanks, Harald > Jonathan > >> >>>> }; >>>> >>>> Example for i.MX28 SoC: >>>> @@ -44,4 +63,14 @@ Example for i.MX28 SoC: >>>> fsl,ave-ctrl = <4>; >>>> fsl,ave-delay = <2>; >>>> fsl,settling = <10>; >>>> + >>>> + isrc_lradc0: ISRC0 { >>>> + regulator-max-microamp = <300>; >>>> + }; >>>> + >>>> + isrc_lradc6: ISRC1 { >>>> + regulator-max-microamp = <120>; >>>> + regulator-min-microamp = <120>; >>>> + regulator-always-on; >>>> + }; >>>> }; >>>> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >>>> index 5937030..1968d1c 100644 >>>> --- a/drivers/iio/adc/Kconfig >>>> +++ b/drivers/iio/adc/Kconfig >>>> @@ -319,6 +319,7 @@ config MXS_LRADC >>>> tristate "Freescale i.MX23/i.MX28 LRADC" >>>> depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM >>>> depends on INPUT >>>> + depends on REGULATOR >>> >>> Any chance to avoid this dependency for an optional feature? >> >> I haven't looked into it yet, but I expect that that the mfd >> conversion will avoid this neatly. >> >> Thanks, >> Harald >> >>> Stefan >>> >>>> select STMP_DEVICE >>>> select IIO_BUFFER >>>> select IIO_TRIGGERED_BUFFER >>
diff --git a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt index 555fb11..983952c 100644 --- a/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt +++ b/Documentation/devicetree/bindings/staging/iio/adc/mxs-lradc.txt @@ -19,6 +19,15 @@ Optional properties: - fsl,settling: delay between plate switch to next sample. Allowed value is 1 ... 2047. It counts at 2 kHz and its default is 10 (= 5 ms) +- ISRC0: A node describing the regulator of internal current source 0 +- ISRC1: A node describing the regulator of internal current source 1 + +Required properties for the ISRCx sub-nodes: +- regulator-max-microamp: See standard regulator binding documentation. + Valid values are from 0 to 300 in steps of 20. + +Optional properties for the ISRCx sub-nodes: +Any standard regulator properties that apply to current regulators. Example for i.MX23 SoC: @@ -31,6 +40,16 @@ Example for i.MX23 SoC: fsl,ave-ctrl = <4>; fsl,ave-delay = <2>; fsl,settling = <10>; + + isrc_lradc0: ISRC0 { + regulator-max-microamp = <300>; + }; + + isrc_lradc1: ISRC1 { + regulator-max-microamp = <120>; + regulator-min-microamp = <120>; + regulator-always-on; + }; }; Example for i.MX28 SoC: @@ -44,4 +63,14 @@ Example for i.MX28 SoC: fsl,ave-ctrl = <4>; fsl,ave-delay = <2>; fsl,settling = <10>; + + isrc_lradc0: ISRC0 { + regulator-max-microamp = <300>; + }; + + isrc_lradc6: ISRC1 { + regulator-max-microamp = <120>; + regulator-min-microamp = <120>; + regulator-always-on; + }; }; diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 5937030..1968d1c 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -319,6 +319,7 @@ config MXS_LRADC tristate "Freescale i.MX23/i.MX28 LRADC" depends on (ARCH_MXS || COMPILE_TEST) && HAS_IOMEM depends on INPUT + depends on REGULATOR select STMP_DEVICE select IIO_BUFFER select IIO_TRIGGERED_BUFFER diff --git a/drivers/iio/adc/mxs-lradc.c b/drivers/iio/adc/mxs-lradc.c index 33051b8..f22f339 100644 --- a/drivers/iio/adc/mxs-lradc.c +++ b/drivers/iio/adc/mxs-lradc.c @@ -40,6 +40,10 @@ #include <linux/iio/triggered_buffer.h> #include <linux/iio/sysfs.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/machine.h> +#include <linux/regulator/of_regulator.h> + #define DRIVER_NAME "mxs-lradc" #define LRADC_MAX_DELAY_CHANS 4 @@ -261,6 +265,9 @@ struct mxs_lradc { unsigned over_sample_delay; /* time in clocks to wait after the plates where switched */ unsigned settling_delay; + + struct regulator_desc isrc0; + struct regulator_desc isrc1; }; #define LRADC_CTRL0 0x00 @@ -305,6 +312,11 @@ struct mxs_lradc { #define LRADC_CTRL2 0x20 #define LRADC_CTRL2_DIVIDE_BY_TWO_OFFSET 24 #define LRADC_CTRL2_TEMPSENSE_PWD BIT(15) +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE1 BIT(9) +#define LRADC_CTRL2_TEMP_SENSOR_IENABLE0 BIT(8) +#define LRADC_CTRL2_TEMP_ISRC1_OFFSET 4 +#define LRADC_CTRL2_TEMP_ISRC0_OFFSET 0 +#define LRADC_CTRL2_TEMP_ISRC_MASK 0x0f #define LRADC_STATUS 0x40 #define LRADC_STATUS_TOUCH_DETECT_RAW BIT(0) @@ -1383,6 +1395,109 @@ static const struct iio_buffer_setup_ops mxs_lradc_buffer_ops = { .validate_scan_mask = &mxs_lradc_validate_scan_mask, }; +static int mxs_lradc_regulator_is_enabled(struct regulator_dev *dev) +{ + struct mxs_lradc *lradc = rdev_get_drvdata(dev); + int reg = readl(lradc->base + LRADC_CTRL2); + + if (dev->desc == &lradc->isrc0) + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE0; + else if (dev->desc == &lradc->isrc1) + return reg & LRADC_CTRL2_TEMP_SENSOR_IENABLE1; + + /* This should never happen */ + return -ENODEV; +} + +#define LRADC_REGVALUE2uA(regval, offset) \ + (20 * ((regval >> offset) & LRADC_CTRL2_TEMP_ISRC_MASK)) + +static int mxs_lradc_regulator_get_current_limit(struct regulator_dev *dev) +{ + struct mxs_lradc *lradc = rdev_get_drvdata(dev); + int reg = readl(lradc->base + LRADC_CTRL2); + + if (dev->desc == &lradc->isrc0) + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC0_OFFSET); + else if (dev->desc == &lradc->isrc1) + return LRADC_REGVALUE2uA(reg, LRADC_CTRL2_TEMP_ISRC1_OFFSET); + + /* This should never happen */ + return -ENODEV; +} + +static int mxs_lradc_regulator_enable(struct regulator_dev *dev) +{ + struct mxs_lradc *lradc = rdev_get_drvdata(dev); + + if (dev->desc == &lradc->isrc0) + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, + LRADC_CTRL2); + else if (dev->desc == &lradc->isrc1) + mxs_lradc_reg_set(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, + LRADC_CTRL2); + else + /* This should never happen */ + return -ENODEV; + + return 0; +} + +static int mxs_lradc_regulator_disable(struct regulator_dev *dev) +{ + struct mxs_lradc *lradc = rdev_get_drvdata(dev); + + if (dev->desc == &lradc->isrc0) + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0, + LRADC_CTRL2); + else if (dev->desc == &lradc->isrc1) + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE1, + LRADC_CTRL2); + else + /* This should never happen */ + return -ENODEV; + + return 0; +} + +static int mxs_lradc_regulator_set_current_limit(struct regulator_dev *dev, + int min_uA, int max_uA) +{ + struct mxs_lradc *lradc = rdev_get_drvdata(dev); + int offset, value; + + if (dev->desc == &lradc->isrc0) + offset = LRADC_CTRL2_TEMP_ISRC0_OFFSET; + else if (dev->desc == &lradc->isrc1) + offset = LRADC_CTRL2_TEMP_ISRC1_OFFSET; + else + /* This should never happen */ + return -ENODEV; + + value = min_uA / 20; + if (min_uA % 20) + value++; + if (value * 20 > max_uA) + return -EINVAL; + if (value & ~LRADC_CTRL2_TEMP_ISRC_MASK) + /* This should never happen */ + return -EPERM; + + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_ISRC_MASK << offset, + LRADC_CTRL2); + mxs_lradc_reg_set(lradc, value << offset, LRADC_CTRL2); + + return 0; +} + +static struct regulator_ops mxs_lradc_regulator_current_ops = { + .enable = mxs_lradc_regulator_enable, + .is_enabled = mxs_lradc_regulator_is_enabled, + .disable = mxs_lradc_regulator_disable, + .get_current_limit = mxs_lradc_regulator_get_current_limit, + .set_current_limit = mxs_lradc_regulator_set_current_limit, +}; + /* * Driver initialization */ @@ -1519,6 +1634,10 @@ static void mxs_lradc_hw_stop(struct mxs_lradc *lradc) for (i = 0; i < LRADC_MAX_DELAY_CHANS; i++) mxs_lradc_reg_wrt(lradc, 0, LRADC_DELAY(i)); + + mxs_lradc_reg_clear(lradc, LRADC_CTRL2_TEMP_SENSOR_IENABLE0 | + LRADC_CTRL2_TEMP_SENSOR_IENABLE1, + LRADC_CTRL2); } static const struct of_device_id mxs_lradc_dt_ids[] = { @@ -1592,6 +1711,32 @@ static int mxs_lradc_probe_touchscreen(struct mxs_lradc *lradc, return 0; } +static void mxs_lradc_reg_helper(struct device_node *np, const char *name, + struct regulator_config *conf, + struct regulator_desc *desc) +{ + struct regulator_dev *ret; + + conf->of_node = of_get_child_by_name(np, name); + if (!conf->of_node) + return; + + desc->name = name; + desc->owner = THIS_MODULE; + desc->type = REGULATOR_CURRENT; + desc->ops = &mxs_lradc_regulator_current_ops; + + conf->init_data = of_get_regulator_init_data(conf->dev, conf->of_node, + desc); + ret = devm_regulator_register(conf->dev, desc, conf); + if (IS_ERR(ret)) + /* Just pretend the regulator isn't there */ + dev_err(conf->dev, "Failed to register regulator %s: %ld\n", + desc->name, PTR_ERR(ret)); + + of_node_put(conf->of_node); +} + static int mxs_lradc_probe(struct platform_device *pdev) { const struct of_device_id *of_id = @@ -1603,6 +1748,7 @@ static int mxs_lradc_probe(struct platform_device *pdev) struct mxs_lradc *lradc; struct iio_dev *iio; struct resource *iores; + struct regulator_config regconf; int ret = 0, touch_ret; int i, s; u64 scale_uv; @@ -1727,6 +1873,12 @@ static int mxs_lradc_probe(struct platform_device *pdev) goto err_ts; } + /* Setup regulator devices for current source. */ + regconf.dev = dev; + regconf.driver_data = lradc; + mxs_lradc_reg_helper(node, "ISRC0", ®conf, &lradc->isrc0); + mxs_lradc_reg_helper(node, "ISRC1", ®conf, &lradc->isrc1); + return 0; err_ts:
The hardware has two current sources ISRC0 and ISRC1 to allow measuring resistors without additional circuitry. This commit makes them available as regulators. Tested on an imx233-olinuxino board. Signed-off-by: Harald Geyer <harald@ccbib.org> --- The current regulator API doesn't fit this type of device very well: Typically consumers will want to set a defined current, ie. min_uA == max_uA, but they can't without help from configuration data, because the valid values aren't reported by the API for current regulators. I have been thinking about extending the API, but currently AFAIK no such consumers exist and most users, like myself, will force the regulator to a defined value in devicetree anyway. .../bindings/staging/iio/adc/mxs-lradc.txt | 29 ++++ drivers/iio/adc/Kconfig | 1 + drivers/iio/adc/mxs-lradc.c | 152 +++++++++++++++++++++ 3 files changed, 182 insertions(+)