| Message ID | 1402672899-6995-3-git-send-email-denis@eukrea.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Denis, On Fri, Jun 13, 2014 at 05:21:35PM +0200, Denis Carikli wrote: > + > + if (ret == 0 && samples != 0) { > + /* > + * only if both touch measures are below a treshold, > + * the position is valid > + */ > + if (touch_pre < priv->pen_threshold && > + touch_post < priv->pen_threshold) { > + /* valid samples, generate a report */ > + x_pos /= priv->sample_count; > + y_pos /= priv->sample_count; > + input_report_abs(priv->idev, ABS_X, x_pos); > + input_report_abs(priv->idev, ABS_Y, y_pos); > + input_report_key(priv->idev, BTN_TOUCH, > + 0xfff - ((touch_pre + touch_post) / 2)); I still do not understand this calculation. input_report_key() converts the last argument to a boolean, so the only time it would report BTN_TOUCH UP here if (touch_pre + touch_post) / 2 is exactly 0xfff. Given that default threshold is 500 this won't ever happen. Why isn't it simply: input_report_key(priv->idev, BTN_TOUCH, 1); ? ... > + > +static irqreturn_t mx25_tcq_irq_thread(int irq, void *dev_id) > +{ > + struct mx25_tcq_priv *priv = (struct mx25_tcq_priv *) dev_id; No need to cast. > + u32 sample_buf[TSC_MAX_SAMPLES]; > + int samples = 0; > + > + /* read all samples */ > + while (1) { > + u32 stats; > + > + regmap_read(priv->regs, MX25_ADCQ_SR, &stats); > + if (stats & MX25_ADCQ_SR_EMPT) > + break; > + > + if (samples < TSC_MAX_SAMPLES) { > + regmap_read(priv->regs, MX25_ADCQ_FIFO, > + &sample_buf[samples]); > + ++samples; > + } else { > + u32 discarded; > + /* discard samples */ > + regmap_read(priv->regs, MX25_ADCQ_FIFO, &discarded); > + } > + } > + > + mx25_tcq_create_event_for_4wire(priv, sample_buf, samples); > + > + return IRQ_HANDLED; > +} > + > +static irqreturn_t mx25_tcq_irq(int irq, void *dev_id) > +{ > + struct mx25_tcq_priv *priv = (struct mx25_tcq_priv *)dev_id; Same here. > + u32 stat; > + int ret = IRQ_HANDLED; > + > + regmap_read(priv->regs, MX25_ADCQ_SR, &stat); > + > + if (stat & (MX25_ADCQ_SR_FRR | MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR)) > + mx25_tcq_fifo_reset(priv); > + > + if (stat & MX25_ADCQ_SR_PD) { > + mx25_tcq_disable_touch_irq(priv); > + mx25_tcq_force_queue_start(priv); > + mx25_tcq_enable_fifo_irq(priv); > + } > + > + if (stat & MX25_ADCQ_SR_FDRY) { > + mx25_tcq_disable_fifo_irq(priv); > + ret = IRQ_WAKE_THREAD; > + } > + > + regmap_update_bits(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_FRR | > + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | MX25_ADCQ_SR_PD | > + MX25_ADCQ_SR_EOQ, > + MX25_ADCQ_SR_FRR | > + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | MX25_ADCQ_SR_PD | > + MX25_ADCQ_SR_EOQ); > + > + return ret; > +} > + > +/* configure the statemachine for a 4-wire touchscreen */ > +static int mx25_tcq_init(struct mx25_tcq_priv *priv) > +{ > + u32 tgcr; > + unsigned int ipg_div; > + unsigned int adc_period; > + unsigned int debounce_cnt; > + unsigned int settling_time; > + int itemct; > + int ret; > + > + regmap_read(priv->core_regs, MX25_TSC_TGCR, &tgcr); > + ipg_div = max_t(unsigned int, 4, MX25_TGCR_GET_ADCCLK(tgcr)); > + adc_period = clk_get_rate(priv->clk) / (ipg_div * 2 + 2); > + debounce_cnt = DIV_ROUND_UP(priv->pen_debounce, adc_period * 8) - 1; > + settling_time = DIV_ROUND_UP(priv->settling_time, adc_period); > + > + > + /* Reset */ > + regmap_write(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QRST | > + MX25_ADCQ_CR_FRST); > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QRST | > + MX25_ADCQ_CR_FRST, 0); > + > + /* up to 128 * 8 ADC clocks are possible */ > + if (debounce_cnt > 127) > + debounce_cnt = 127; > + > + ret = imx25_setup_queue_4wire(priv, 0x0, &itemct); > + if (ret) > + return ret; > + > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_LITEMID_MASK | > + MX25_ADCQ_CR_WMRK_MASK, > + MX25_ADCQ_CR_LITEMID(itemct - 1) | > + MX25_ADCQ_CR_WMRK(priv->expected_samples - 1)); > + > + /* setup debounce count */ > + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, > + MX25_TGCR_PDBTIME_MASK, > + MX25_TGCR_PDBTIME(debounce_cnt)); > + > + /* enable debounce */ > + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, MX25_TGCR_PDBEN, > + MX25_TGCR_PDBEN); > + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, MX25_TGCR_PDEN, > + MX25_TGCR_PDEN); > + > + /* enable the engine on demand */ > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QSM_FQS, > + MX25_ADCQ_CR_QSM_FQS); > + > + mx25_tcq_re_enable_touch_detection(priv); > + > + return 0; > +} > + > +static int mx25_tcq_parse_dt(struct platform_device *pdev, > + struct mx25_tcq_priv *priv) > +{ > + struct device_node *np = pdev->dev.of_node; > + u32 wires; > + int ret; > + > + /* Setup defaults */ > + priv->pen_threshold = 500; > + priv->sample_count = 3; > + priv->pen_debounce = 1000000; > + priv->settling_time = 250000; > + > + ret = of_property_read_u32(np, "fsl,wires", &wires); > + if (ret) { > + dev_err(&pdev->dev, "Failed to find fsl,wires properties\n"); > + return ret; > + } > + > + if (wires == 4) { > + priv->mode = MX25_TS_4WIRE; > + } else { > + dev_err(&pdev->dev, "%u-wire mode not supported\n", wires); > + return -EINVAL; > + } > + > + /* These are optional, we don't care about the return values */ > + of_property_read_u32(np, "fsl,pen-threshold", &priv->pen_threshold); > + of_property_read_u32(np, "fsl,settling-time", &priv->settling_time); > + of_property_read_u32(np, "fsl,pen-debounce", &priv->pen_debounce); > + > + return 0; > +} > + > +static int mx25_tcq_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct input_dev *idev; > + struct mx25_tcq_priv *priv; > + struct resource *res; > + void __iomem *mem; > + int ret; > + int irq; > + > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + mem = devm_ioremap_resource(dev, res); > + if (!mem) > + return -ENOMEM; > + > + ret = mx25_tcq_parse_dt(pdev, priv); > + if (ret) > + return ret; > + > + priv->regs = devm_regmap_init_mmio(dev, mem, &mx25_tcq_regconfig); > + if (IS_ERR(priv->regs)) { > + dev_err(dev, "Failed to initialize regmap\n"); > + return PTR_ERR(priv->regs); > + } > + > + irq = platform_get_irq(pdev, 0); > + if (irq <= 0) { > + dev_err(dev, "Failed to get IRQ\n"); > + return irq; > + } > + > + idev = devm_input_allocate_device(dev); > + if (!idev) { > + dev_err(dev, "Failed to allocate input device\n"); > + return -ENOMEM; > + } > + > + idev->name = mx25_tcq_name; > + idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); > + idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); > + input_set_abs_params(idev, ABS_X, 0, 0xfff, 0, 0); > + input_set_abs_params(idev, ABS_Y, 0, 0xfff, 0, 0); > + > + idev->id.bustype = BUS_HOST; > + > + ret = input_register_device(idev); > + if (ret) { > + dev_err(dev, "Failed to register input device\n"); > + return ret; > + } > + > + priv->idev = idev; > + > + priv->core_regs = mx25_tsadc_get_regmap(pdev->dev.parent); > + priv->clk = mx25_tsadc_get_ipg(pdev->dev.parent); > + > + ret = clk_prepare_enable(priv->clk); > + if (ret) { > + dev_err(dev, "Failed to enable ipg clock\n"); > + return ret; > + } > + > + ret = devm_request_threaded_irq(dev, irq, mx25_tcq_irq, > + mx25_tcq_irq_thread, IRQF_ONESHOT, pdev->name, priv); > + if (ret) { > + dev_err(dev, "Failed requesting IRQ\n"); You are leaving clock enabled here. > + return ret; > + } > + > + ret = mx25_tcq_init(priv); > + if (ret) { > + dev_err(dev, "Failed to init tcq\n"); > + goto error_tcq_init; > + } > + > + platform_set_drvdata(pdev, priv); > + > + return 0; > + > +error_tcq_init: > + clk_disable_unprepare(priv->clk); > + return ret; > +} > + > +static int mx25_tcq_remove(struct platform_device *pdev) > +{ > + struct mx25_tcq_priv *priv = platform_get_drvdata(pdev); > + > + clk_disable_unprepare(priv->clk); > + > + return 0; > +} > + > +static struct platform_driver mx25_tcq_driver = { > + .driver = { > + .name = "mx25-tcq", > + .owner = THIS_MODULE, > + .of_match_table = mx25_tcq_ids, > + }, > + .probe = mx25_tcq_probe, > + .remove = mx25_tcq_remove, > +}; > +module_platform_driver(mx25_tcq_driver); > + > +MODULE_DESCRIPTION("TS input driver for Freescale mx25"); > +MODULE_AUTHOR("Markus Pargmann <mpa@pengutronix.de>"); > +MODULE_LICENSE("GPL v2"); > -- > 1.7.9.5 > Thanks.
On 13/06/14 16:21, Denis Carikli wrote: > From: Markus Pargmann <mpa@pengutronix.de> > > This is a driver for the imx25 ADC/TSC module. It controls the > touchscreen conversion queue and creates a touchscreen input device. > The driver currently only supports 4 wire touchscreens. The driver uses > a simple conversion queue of precharge, touch detection, X measurement, > Y measurement, precharge and another touch detection. > > This driver uses the regmap from the parent to setup some touch specific > settings in the core driver and setup a idle configuration with touch > detection. > > Signed-off-by: Markus Pargmann <mpa@pengutronix.de> > Signed-off-by: Denis Carikli <denis@eukrea.com> A couple of little bits inline. I haven't looked in detail by the devm irq handling looks dangerous as the clock is set to running before this is enabled, but disabled before it is disabled. Jonathan > --- > .../bindings/input/touchscreen/fsl-mx25-tcq.txt | 29 + > drivers/input/touchscreen/Kconfig | 6 + > drivers/input/touchscreen/Makefile | 1 + > drivers/input/touchscreen/fsl-imx25-tcq.c | 576 ++++++++++++++++++++ > 4 files changed, 612 insertions(+) > create mode 100644 Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt > create mode 100644 drivers/input/touchscreen/fsl-imx25-tcq.c > > diff --git a/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt b/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt > new file mode 100644 > index 0000000..4214a99 > --- /dev/null > +++ b/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt > @@ -0,0 +1,29 @@ > +Freescale mx25 TS conversion queue module > + > +mx25 touchscreen conversion queue module which controls the ADC unit of the > +mx25 for attached touchscreens. > + > +Required properties: > + - compatible: Should be "fsl,imx25-tcq". > + - reg: Memory range of the device. > + - interrupts: Should be the interrupt number associated with this module within > + the tscadc unit (<0>). > + - interrupt-parent: Should be a phandle to the tscadc unit. > + - fsl,wires: Should be '<4>' or '<5>' > + > +Optional properties: > + - fsl,pen-debounce: Pen debounce time. > + - fsl,pen-threshold: Pen-down threshold for the touchscreen. > + - fsl,settling-time: Settling time in nanoseconds. > + > +This device includes two conversion queues which can be added as subnodes. > +The first queue is for the touchscreen, the second for general purpose ADC. > + > +Example: > + tsc: tcq@50030400 { > + compatible = "fsl,imx25-tcq"; > + reg = <0x50030400 0x60>; > + interrupt-parent = <&tscadc>; > + interrupts = <0>; > + fsl,wires = <4>; > + }; > diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig > index a23a94b..a2290b9 100644 > --- a/drivers/input/touchscreen/Kconfig > +++ b/drivers/input/touchscreen/Kconfig > @@ -699,6 +699,12 @@ config TOUCHSCREEN_USB_COMPOSITE > To compile this driver as a module, choose M here: the > module will be called usbtouchscreen. > > +config TOUCHSCREEN_MX25 > + tristate "Freescale i.MX25 touchscreen input driver" > + depends on MFD_MX25_TSADC > + help > + Enable support for touchscreen connected to your i.MX25. > + > config TOUCHSCREEN_MC13783 > tristate "Freescale MC13783 touchscreen input driver" > depends on MFD_MC13XXX > diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile > index 126479d..537d591 100644 > --- a/drivers/input/touchscreen/Makefile > +++ b/drivers/input/touchscreen/Makefile > @@ -38,6 +38,7 @@ obj-$(CONFIG_TOUCHSCREEN_INEXIO) += inexio.o > obj-$(CONFIG_TOUCHSCREEN_INTEL_MID) += intel-mid-touch.o > obj-$(CONFIG_TOUCHSCREEN_LPC32XX) += lpc32xx_ts.o > obj-$(CONFIG_TOUCHSCREEN_MAX11801) += max11801_ts.o > +obj-$(CONFIG_TOUCHSCREEN_MX25) += fsl-imx25-tcq.o > obj-$(CONFIG_TOUCHSCREEN_MC13783) += mc13783_ts.o > obj-$(CONFIG_TOUCHSCREEN_MCS5000) += mcs5000_ts.o > obj-$(CONFIG_TOUCHSCREEN_MIGOR) += migor_ts.o > diff --git a/drivers/input/touchscreen/fsl-imx25-tcq.c b/drivers/input/touchscreen/fsl-imx25-tcq.c > new file mode 100644 > index 0000000..4ce576e > --- /dev/null > +++ b/drivers/input/touchscreen/fsl-imx25-tcq.c > @@ -0,0 +1,576 @@ > +/* > + * Copyright 2014 Markus Pargmann, Pengutronix <mpa@pengutronix.de> > + * Based on driver from 2011: > + * Juergen Beisert, Pengutronix <kernel@pengutronix.de> > + * > + * The code contained herein is licensed under the GNU General Public > + * License. You may obtain a copy of the GNU General Public License > + * Version 2 or later at the following locations: > + * > + * http://www.opensource.org/licenses/gpl-license.html > + * http://www.gnu.org/copyleft/gpl.html > + * > + * This is the driver for the imx25 TCQ (Touchscreen Conversion Queue) > + * connected to the imx25 ADC. > + */ > + > +#include <linux/clk.h> > +#include <linux/interrupt.h> > +#include <linux/input.h> > +#include <linux/mfd/imx25-tsadc.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <linux/platform_device.h> > +#include <linux/regmap.h> > + > +static const char mx25_tcq_name[] = "mx25-tcq"; > + > +enum mx25_tcq_mode { > + MX25_TS_4WIRE, > +}; > + > +struct mx25_tcq_priv { > + struct regmap *regs; > + struct regmap *core_regs; > + struct input_dev *idev; > + enum mx25_tcq_mode mode; > + unsigned int pen_threshold; > + unsigned int sample_count; > + unsigned int expected_samples; > + unsigned int pen_debounce; > + unsigned int settling_time; > + struct clk *clk; > +}; > + > +static struct regmap_config mx25_tcq_regconfig = { > + .fast_io = true, > + .max_register = 0x5c, > + .reg_bits = 32, > + .val_bits = 32, > + .reg_stride = 4, > +}; > + > +static struct of_device_id mx25_tcq_ids[] = { > + { .compatible = "fsl,imx25-tcq", }, > + { /* Senitel */ } > +}; > + > +#define TSC_4WIRE_PRE_INDEX 0 > +#define TSC_4WIRE_X_INDEX 1 > +#define TSC_4WIRE_Y_INDEX 2 > +#define TSC_4WIRE_POST_INDEX 3 > +#define TSC_4WIRE_LEAVE 4 > + > +#define MX25_TSC_DEF_THRESHOLD 80 > +#define TSC_MAX_SAMPLES 16 > + > + > +enum mx25_adc_configurations { > + MX25_CFG_PRECHARGE = 0, > + MX25_CFG_TOUCH_DETECT, > + MX25_CFG_X_MEASUREMENT, > + MX25_CFG_Y_MEASUREMENT, > +}; > + > +#define MX25_PRECHARGE_VALUE (\ > + MX25_ADCQ_CFG_YPLL_OFF | \ > + MX25_ADCQ_CFG_XNUR_OFF | \ > + MX25_ADCQ_CFG_XPUL_HIGH | \ > + MX25_ADCQ_CFG_REFP_INT | \ > + MX25_ADCQ_CFG_IN_XP | \ > + MX25_ADCQ_CFG_REFN_NGND2 | \ > + MX25_ADCQ_CFG_IGS) > + > +#define MX25_TOUCH_DETECT_VALUE (\ > + MX25_ADCQ_CFG_YNLR | \ > + MX25_ADCQ_CFG_YPLL_OFF | \ > + MX25_ADCQ_CFG_XNUR_OFF | \ > + MX25_ADCQ_CFG_XPUL_OFF | \ > + MX25_ADCQ_CFG_REFP_INT | \ > + MX25_ADCQ_CFG_IN_XP | \ > + MX25_ADCQ_CFG_REFN_NGND2 | \ > + MX25_ADCQ_CFG_PENIACK) > + > +static void imx25_setup_queue_cfgs(struct mx25_tcq_priv *priv, > + unsigned int settling_time) > +{ > + u32 precharge_cfg = > + MX25_PRECHARGE_VALUE | > + MX25_ADCQ_CFG_SETTLING_TIME(settling_time); > + u32 touch_detect_cfg = > + MX25_TOUCH_DETECT_VALUE | > + MX25_ADCQ_CFG_NOS(1) | > + MX25_ADCQ_CFG_SETTLING_TIME(settling_time); > + > + regmap_write(priv->core_regs, MX25_TSC_TICR, precharge_cfg); > + > + /* PRECHARGE */ > + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_PRECHARGE), > + precharge_cfg); > + > + /* TOUCH_DETECT */ > + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_TOUCH_DETECT), > + touch_detect_cfg); > + > + /* X Measurement */ > + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_X_MEASUREMENT), > + MX25_ADCQ_CFG_YPLL_OFF | > + MX25_ADCQ_CFG_XNUR_LOW | > + MX25_ADCQ_CFG_XPUL_HIGH | > + MX25_ADCQ_CFG_REFP_XP | > + MX25_ADCQ_CFG_IN_YP | > + MX25_ADCQ_CFG_REFN_XN | > + MX25_ADCQ_CFG_NOS(priv->sample_count) | > + MX25_ADCQ_CFG_SETTLING_TIME(settling_time)); > + > + /* Y Measurement */ > + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_Y_MEASUREMENT), > + MX25_ADCQ_CFG_YNLR | > + MX25_ADCQ_CFG_YPLL_HIGH | > + MX25_ADCQ_CFG_XNUR_OFF | > + MX25_ADCQ_CFG_XPUL_OFF | > + MX25_ADCQ_CFG_REFP_YP | > + MX25_ADCQ_CFG_IN_XP | > + MX25_ADCQ_CFG_REFN_YN | > + MX25_ADCQ_CFG_NOS(priv->sample_count) | > + MX25_ADCQ_CFG_SETTLING_TIME(settling_time)); > + > + /* Enable the touch detection right now */ > + regmap_write(priv->core_regs, MX25_TSC_TICR, touch_detect_cfg | > + MX25_ADCQ_CFG_IGS); > +} > + > +static int imx25_setup_queue_4wire(struct mx25_tcq_priv *priv, > + unsigned settling_time, int *items) > +{ > + imx25_setup_queue_cfgs(priv, settling_time); > + > + /* Setup the conversion queue */ > + regmap_write(priv->regs, MX25_ADCQ_ITEM_7_0, > + MX25_ADCQ_ITEM(0, MX25_CFG_PRECHARGE) | > + MX25_ADCQ_ITEM(1, MX25_CFG_TOUCH_DETECT) | > + MX25_ADCQ_ITEM(2, MX25_CFG_X_MEASUREMENT) | > + MX25_ADCQ_ITEM(3, MX25_CFG_Y_MEASUREMENT) | > + MX25_ADCQ_ITEM(4, MX25_CFG_PRECHARGE) | > + MX25_ADCQ_ITEM(5, MX25_CFG_TOUCH_DETECT)); > + > + /* We measure X/Y with 'sample_count' number of samples and execute a > + * touch detection twice, with 1 sample each */ > + priv->expected_samples = priv->sample_count * 2 + 2; > + *items = 6; > + > + return 0; > +} > + > +static void mx25_tcq_disable_touch_irq(struct mx25_tcq_priv *priv) > +{ > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_PDMSK, > + MX25_ADCQ_CR_PDMSK); > +} > + > +static void mx25_tcq_enable_touch_irq(struct mx25_tcq_priv *priv) > +{ > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_PDMSK, 0); > +} > + > +static void mx25_tcq_disable_fifo_irq(struct mx25_tcq_priv *priv) > +{ > + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_FDRY_IRQ, > + MX25_ADCQ_MR_FDRY_IRQ); > +} > + > +static void mx25_tcq_enable_fifo_irq(struct mx25_tcq_priv *priv) > +{ > + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_FDRY_IRQ, 0); > +} > + > +static void mx25_tcq_force_queue_start(struct mx25_tcq_priv *priv) > +{ > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, > + MX25_ADCQ_CR_FQS); > + > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0); > +} > + > +static void mx25_tcq_force_queue_stop(struct mx25_tcq_priv *priv) > +{ > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0); > +} > + > +static void mx25_tcq_fifo_reset(struct mx25_tcq_priv *priv) > +{ > + u32 tcqcr; > + > + regmap_read(priv->regs, MX25_ADCQ_CR, &tcqcr); > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FRST, > + MX25_ADCQ_CR_FRST); > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FRST, > + 0); > + regmap_write(priv->regs, MX25_ADCQ_CR, tcqcr); > +} > + > +static void mx25_tcq_re_enable_touch_detection(struct mx25_tcq_priv *priv) > +{ > + /* stop the queue from looping */ > + mx25_tcq_force_queue_stop(priv); > + > + /* for a clean touch detection, preload the X plane */ > + regmap_write(priv->core_regs, MX25_TSC_TICR, MX25_PRECHARGE_VALUE); > + > + /* waste some time now to pre-load the X plate to high voltage */ > + mx25_tcq_fifo_reset(priv); > + > + /* re-enable the detection right now */ > + regmap_write(priv->core_regs, MX25_TSC_TICR, MX25_TOUCH_DETECT_VALUE | > + MX25_ADCQ_CFG_IGS); > + > + regmap_update_bits(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_PD, > + MX25_ADCQ_SR_PD); > + > + /* enable the pen down event to be a source for the interrupt */ > + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_PD_IRQ, 0); > + > + /* lets fire the next IRQ if someone touches the touchscreen */ > + mx25_tcq_enable_touch_irq(priv); > +} > + > +static int mx25_tcq_create_event_for_4wire(struct mx25_tcq_priv *priv, > + u32 *sample_buf, int samples) > +{ > + unsigned int x_pos = 0; > + unsigned int y_pos = 0; > + unsigned int touch_pre = 0; > + unsigned int touch_post = 0; > + unsigned i; > + int ret = 0; > + > + for (i = 0; i < samples; i++) { > + unsigned int index = MX25_ADCQ_FIFO_ID(sample_buf[i]); > + unsigned int val = MX25_ADCQ_FIFO_DATA(sample_buf[i]); > + > + switch (index) { > + case 1: > + touch_pre = val; > + break; > + case 2: > + x_pos = val; > + break; > + case 3: > + y_pos = val; > + break; > + case 5: > + touch_post = val; > + break; > + default: > + ret = -EINVAL; > + break; > + } > + } > + > + if (ret == 0 && samples != 0) { > + /* > + * only if both touch measures are below a treshold, > + * the position is valid > + */ > + if (touch_pre < priv->pen_threshold && > + touch_post < priv->pen_threshold) { > + /* valid samples, generate a report */ > + x_pos /= priv->sample_count; > + y_pos /= priv->sample_count; > + input_report_abs(priv->idev, ABS_X, x_pos); > + input_report_abs(priv->idev, ABS_Y, y_pos); > + input_report_key(priv->idev, BTN_TOUCH, > + 0xfff - ((touch_pre + touch_post) / 2)); > + input_sync(priv->idev); > + > + /* get next sample */ > + mx25_tcq_force_queue_start(priv); > + mx25_tcq_enable_fifo_irq(priv); > + } else if (touch_pre >= priv->pen_threshold && > + touch_post >= priv->pen_threshold) { > + /* > + * if both samples are invalid, > + * generate a release report > + */ > + input_report_key(priv->idev, BTN_TOUCH, 0); > + input_sync(priv->idev); > + mx25_tcq_re_enable_touch_detection(priv); > + } else { > + /* > + * if only one of both touch measurements are > + * below the threshold, still some bouncing > + * happens. Take additional samples in this > + * case to be sure > + */ > + mx25_tcq_force_queue_start(priv); > + mx25_tcq_enable_fifo_irq(priv); > + } > + } > + > + return ret; > +} > + > +static irqreturn_t mx25_tcq_irq_thread(int irq, void *dev_id) > +{ > + struct mx25_tcq_priv *priv = (struct mx25_tcq_priv *) dev_id; > + u32 sample_buf[TSC_MAX_SAMPLES]; > + int samples = 0; > + > + /* read all samples */ > + while (1) { > + u32 stats; > + > + regmap_read(priv->regs, MX25_ADCQ_SR, &stats); > + if (stats & MX25_ADCQ_SR_EMPT) > + break; > + > + if (samples < TSC_MAX_SAMPLES) { > + regmap_read(priv->regs, MX25_ADCQ_FIFO, > + &sample_buf[samples]); > + ++samples; > + } else { > + u32 discarded; > + /* discard samples */ > + regmap_read(priv->regs, MX25_ADCQ_FIFO, &discarded); > + } > + } > + > + mx25_tcq_create_event_for_4wire(priv, sample_buf, samples); > + > + return IRQ_HANDLED; > +} > + > +static irqreturn_t mx25_tcq_irq(int irq, void *dev_id) > +{ > + struct mx25_tcq_priv *priv = (struct mx25_tcq_priv *)dev_id; > + u32 stat; > + int ret = IRQ_HANDLED; > + > + regmap_read(priv->regs, MX25_ADCQ_SR, &stat); > + > + if (stat & (MX25_ADCQ_SR_FRR | MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR)) > + mx25_tcq_fifo_reset(priv); > + > + if (stat & MX25_ADCQ_SR_PD) { > + mx25_tcq_disable_touch_irq(priv); > + mx25_tcq_force_queue_start(priv); > + mx25_tcq_enable_fifo_irq(priv); > + } > + > + if (stat & MX25_ADCQ_SR_FDRY) { > + mx25_tcq_disable_fifo_irq(priv); > + ret = IRQ_WAKE_THREAD; > + } > + > + regmap_update_bits(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_FRR | > + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | MX25_ADCQ_SR_PD | > + MX25_ADCQ_SR_EOQ, > + MX25_ADCQ_SR_FRR | > + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | MX25_ADCQ_SR_PD | > + MX25_ADCQ_SR_EOQ); > + > + return ret; > +} > + > +/* configure the statemachine for a 4-wire touchscreen */ > +static int mx25_tcq_init(struct mx25_tcq_priv *priv) > +{ > + u32 tgcr; > + unsigned int ipg_div; > + unsigned int adc_period; > + unsigned int debounce_cnt; > + unsigned int settling_time; > + int itemct; > + int ret; > + > + regmap_read(priv->core_regs, MX25_TSC_TGCR, &tgcr); > + ipg_div = max_t(unsigned int, 4, MX25_TGCR_GET_ADCCLK(tgcr)); > + adc_period = clk_get_rate(priv->clk) / (ipg_div * 2 + 2); > + debounce_cnt = DIV_ROUND_UP(priv->pen_debounce, adc_period * 8) - 1; > + settling_time = DIV_ROUND_UP(priv->settling_time, adc_period); > + > + > + /* Reset */ > + regmap_write(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QRST | > + MX25_ADCQ_CR_FRST); > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QRST | > + MX25_ADCQ_CR_FRST, 0); > + > + /* up to 128 * 8 ADC clocks are possible */ > + if (debounce_cnt > 127) > + debounce_cnt = 127; > + > + ret = imx25_setup_queue_4wire(priv, 0x0, &itemct); > + if (ret) > + return ret; > + > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_LITEMID_MASK | > + MX25_ADCQ_CR_WMRK_MASK, > + MX25_ADCQ_CR_LITEMID(itemct - 1) | > + MX25_ADCQ_CR_WMRK(priv->expected_samples - 1)); > + > + /* setup debounce count */ > + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, > + MX25_TGCR_PDBTIME_MASK, > + MX25_TGCR_PDBTIME(debounce_cnt)); > + > + /* enable debounce */ > + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, MX25_TGCR_PDBEN, > + MX25_TGCR_PDBEN); > + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, MX25_TGCR_PDEN, > + MX25_TGCR_PDEN); > + > + /* enable the engine on demand */ > + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QSM_FQS, > + MX25_ADCQ_CR_QSM_FQS); > + > + mx25_tcq_re_enable_touch_detection(priv); > + > + return 0; > +} > + > +static int mx25_tcq_parse_dt(struct platform_device *pdev, > + struct mx25_tcq_priv *priv) > +{ > + struct device_node *np = pdev->dev.of_node; > + u32 wires; > + int ret; > + > + /* Setup defaults */ > + priv->pen_threshold = 500; > + priv->sample_count = 3; > + priv->pen_debounce = 1000000; > + priv->settling_time = 250000; > + > + ret = of_property_read_u32(np, "fsl,wires", &wires); > + if (ret) { > + dev_err(&pdev->dev, "Failed to find fsl,wires properties\n"); > + return ret; > + } > + > + if (wires == 4) { > + priv->mode = MX25_TS_4WIRE; > + } else { > + dev_err(&pdev->dev, "%u-wire mode not supported\n", wires); > + return -EINVAL; > + } > + > + /* These are optional, we don't care about the return values */ > + of_property_read_u32(np, "fsl,pen-threshold", &priv->pen_threshold); > + of_property_read_u32(np, "fsl,settling-time", &priv->settling_time); > + of_property_read_u32(np, "fsl,pen-debounce", &priv->pen_debounce); > + > + return 0; > +} > + > +static int mx25_tcq_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct input_dev *idev; > + struct mx25_tcq_priv *priv; > + struct resource *res; > + void __iomem *mem; > + int ret; > + int irq; > + > + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); > + if (!priv) > + return -ENOMEM; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); Could this not in theory fail? > + mem = devm_ioremap_resource(dev, res); > + if (!mem) > + return -ENOMEM; > + > + ret = mx25_tcq_parse_dt(pdev, priv); > + if (ret) > + return ret; > + > + priv->regs = devm_regmap_init_mmio(dev, mem, &mx25_tcq_regconfig); > + if (IS_ERR(priv->regs)) { > + dev_err(dev, "Failed to initialize regmap\n"); > + return PTR_ERR(priv->regs); > + } > + > + irq = platform_get_irq(pdev, 0); > + if (irq <= 0) { > + dev_err(dev, "Failed to get IRQ\n"); > + return irq; > + } > + > + idev = devm_input_allocate_device(dev); > + if (!idev) { > + dev_err(dev, "Failed to allocate input device\n"); > + return -ENOMEM; > + } > + > + idev->name = mx25_tcq_name; > + idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); > + idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); > + input_set_abs_params(idev, ABS_X, 0, 0xfff, 0, 0); > + input_set_abs_params(idev, ABS_Y, 0, 0xfff, 0, 0); > + > + idev->id.bustype = BUS_HOST; > + > + ret = input_register_device(idev); > + if (ret) { > + dev_err(dev, "Failed to register input device\n"); > + return ret; > + } > + > + priv->idev = idev; > + > + priv->core_regs = mx25_tsadc_get_regmap(pdev->dev.parent); > + priv->clk = mx25_tsadc_get_ipg(pdev->dev.parent); > + > + ret = clk_prepare_enable(priv->clk); > + if (ret) { > + dev_err(dev, "Failed to enable ipg clock\n"); > + return ret; > + } > + > + ret = devm_request_threaded_irq(dev, irq, mx25_tcq_irq, > + mx25_tcq_irq_thread, IRQF_ONESHOT, pdev->name, priv); > + if (ret) { > + dev_err(dev, "Failed requesting IRQ\n"); > + return ret; > + } This use of devm_request_threaded_irq strikes me as potentially dangerous as the order in removing the device has the clock being disabled before the interrupt is removed whereas for a simple unwinding they would be in the other order. > + > + ret = mx25_tcq_init(priv); > + if (ret) { > + dev_err(dev, "Failed to init tcq\n"); > + goto error_tcq_init; > + } > + > + platform_set_drvdata(pdev, priv); > + > + return 0; > + > +error_tcq_init: > + clk_disable_unprepare(priv->clk); > + return ret; > +} > + > +static int mx25_tcq_remove(struct platform_device *pdev) > +{ > + struct mx25_tcq_priv *priv = platform_get_drvdata(pdev); > + > + clk_disable_unprepare(priv->clk); > + > + return 0; > +} > + > +static struct platform_driver mx25_tcq_driver = { > + .driver = { > + .name = "mx25-tcq", > + .owner = THIS_MODULE, > + .of_match_table = mx25_tcq_ids, > + }, > + .probe = mx25_tcq_probe, > + .remove = mx25_tcq_remove, > +}; > +module_platform_driver(mx25_tcq_driver); > + > +MODULE_DESCRIPTION("TS input driver for Freescale mx25"); > +MODULE_AUTHOR("Markus Pargmann <mpa@pengutronix.de>"); > +MODULE_LICENSE("GPL v2"); >
On Sat, Jun 21, 2014 at 7:18 AM, Jonathan Cameron <jic23@kernel.org> wrote: >> + >> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > > Could this not in theory fail? Yes, but devm_ioremap_resource will take care of it, so we don't need to check for error here. > >> + mem = devm_ioremap_resource(dev, res); >> + if (!mem) >> + return -ENOMEM;
On 21/06/14 20:55, Fabio Estevam wrote: > On Sat, Jun 21, 2014 at 7:18 AM, Jonathan Cameron <jic23@kernel.org> wrote: >>> + >>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >> >> Could this not in theory fail? > > Yes, but devm_ioremap_resource will take care of it, so we don't need > to check for error here. Nothing like counter intuitive behaviour. Ah well. Thanks for explaining this! > >> >>> + mem = devm_ioremap_resource(dev, res); >>> + if (!mem) >>> + return -ENOMEM;
On Sun, Jun 29, 2014 at 12:00:20PM +0100, Jonathan Cameron wrote: > On 21/06/14 20:55, Fabio Estevam wrote: >> On Sat, Jun 21, 2014 at 7:18 AM, Jonathan Cameron <jic23@kernel.org> wrote: >>>> + >>>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >>> >>> Could this not in theory fail? >> >> Yes, but devm_ioremap_resource will take care of it, so we don't need >> to check for error here. > Nothing like counter intuitive behaviour. Ah well. > > Thanks for explaining this! Maybe it would be better to have: mem = platform_ioremap_resource(pdev, IORESOURCE_MEM, 0); which wraps up both the platform_get_resource() call with devm_ioremap_resource() so driver writers don't have to be concerned about this aspect?
On 29/06/14 12:49, Russell King - ARM Linux wrote: > On Sun, Jun 29, 2014 at 12:00:20PM +0100, Jonathan Cameron wrote: >> On 21/06/14 20:55, Fabio Estevam wrote: >>> On Sat, Jun 21, 2014 at 7:18 AM, Jonathan Cameron <jic23@kernel.org> wrote: >>>>> + >>>>> + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); >>>> >>>> Could this not in theory fail? >>> >>> Yes, but devm_ioremap_resource will take care of it, so we don't need >>> to check for error here. >> Nothing like counter intuitive behaviour. Ah well. >> >> Thanks for explaining this! > > Maybe it would be better to have: > > mem = platform_ioremap_resource(pdev, IORESOURCE_MEM, 0); > > which wraps up both the platform_get_resource() call with > devm_ioremap_resource() so driver writers don't have to be concerned > about this aspect? > Good idea. Something like that would certainly make more sense to me.
diff --git a/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt b/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt new file mode 100644 index 0000000..4214a99 --- /dev/null +++ b/Documentation/devicetree/bindings/input/touchscreen/fsl-mx25-tcq.txt @@ -0,0 +1,29 @@ +Freescale mx25 TS conversion queue module + +mx25 touchscreen conversion queue module which controls the ADC unit of the +mx25 for attached touchscreens. + +Required properties: + - compatible: Should be "fsl,imx25-tcq". + - reg: Memory range of the device. + - interrupts: Should be the interrupt number associated with this module within + the tscadc unit (<0>). + - interrupt-parent: Should be a phandle to the tscadc unit. + - fsl,wires: Should be '<4>' or '<5>' + +Optional properties: + - fsl,pen-debounce: Pen debounce time. + - fsl,pen-threshold: Pen-down threshold for the touchscreen. + - fsl,settling-time: Settling time in nanoseconds. + +This device includes two conversion queues which can be added as subnodes. +The first queue is for the touchscreen, the second for general purpose ADC. + +Example: + tsc: tcq@50030400 { + compatible = "fsl,imx25-tcq"; + reg = <0x50030400 0x60>; + interrupt-parent = <&tscadc>; + interrupts = <0>; + fsl,wires = <4>; + }; diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index a23a94b..a2290b9 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -699,6 +699,12 @@ config TOUCHSCREEN_USB_COMPOSITE To compile this driver as a module, choose M here: the module will be called usbtouchscreen. +config TOUCHSCREEN_MX25 + tristate "Freescale i.MX25 touchscreen input driver" + depends on MFD_MX25_TSADC + help + Enable support for touchscreen connected to your i.MX25. + config TOUCHSCREEN_MC13783 tristate "Freescale MC13783 touchscreen input driver" depends on MFD_MC13XXX diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 126479d..537d591 100644 --- a/drivers/input/touchscreen/Makefile +++ b/drivers/input/touchscreen/Makefile @@ -38,6 +38,7 @@ obj-$(CONFIG_TOUCHSCREEN_INEXIO) += inexio.o obj-$(CONFIG_TOUCHSCREEN_INTEL_MID) += intel-mid-touch.o obj-$(CONFIG_TOUCHSCREEN_LPC32XX) += lpc32xx_ts.o obj-$(CONFIG_TOUCHSCREEN_MAX11801) += max11801_ts.o +obj-$(CONFIG_TOUCHSCREEN_MX25) += fsl-imx25-tcq.o obj-$(CONFIG_TOUCHSCREEN_MC13783) += mc13783_ts.o obj-$(CONFIG_TOUCHSCREEN_MCS5000) += mcs5000_ts.o obj-$(CONFIG_TOUCHSCREEN_MIGOR) += migor_ts.o diff --git a/drivers/input/touchscreen/fsl-imx25-tcq.c b/drivers/input/touchscreen/fsl-imx25-tcq.c new file mode 100644 index 0000000..4ce576e --- /dev/null +++ b/drivers/input/touchscreen/fsl-imx25-tcq.c @@ -0,0 +1,576 @@ +/* + * Copyright 2014 Markus Pargmann, Pengutronix <mpa@pengutronix.de> + * Based on driver from 2011: + * Juergen Beisert, Pengutronix <kernel@pengutronix.de> + * + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + * + * This is the driver for the imx25 TCQ (Touchscreen Conversion Queue) + * connected to the imx25 ADC. + */ + +#include <linux/clk.h> +#include <linux/interrupt.h> +#include <linux/input.h> +#include <linux/mfd/imx25-tsadc.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> + +static const char mx25_tcq_name[] = "mx25-tcq"; + +enum mx25_tcq_mode { + MX25_TS_4WIRE, +}; + +struct mx25_tcq_priv { + struct regmap *regs; + struct regmap *core_regs; + struct input_dev *idev; + enum mx25_tcq_mode mode; + unsigned int pen_threshold; + unsigned int sample_count; + unsigned int expected_samples; + unsigned int pen_debounce; + unsigned int settling_time; + struct clk *clk; +}; + +static struct regmap_config mx25_tcq_regconfig = { + .fast_io = true, + .max_register = 0x5c, + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + +static struct of_device_id mx25_tcq_ids[] = { + { .compatible = "fsl,imx25-tcq", }, + { /* Senitel */ } +}; + +#define TSC_4WIRE_PRE_INDEX 0 +#define TSC_4WIRE_X_INDEX 1 +#define TSC_4WIRE_Y_INDEX 2 +#define TSC_4WIRE_POST_INDEX 3 +#define TSC_4WIRE_LEAVE 4 + +#define MX25_TSC_DEF_THRESHOLD 80 +#define TSC_MAX_SAMPLES 16 + + +enum mx25_adc_configurations { + MX25_CFG_PRECHARGE = 0, + MX25_CFG_TOUCH_DETECT, + MX25_CFG_X_MEASUREMENT, + MX25_CFG_Y_MEASUREMENT, +}; + +#define MX25_PRECHARGE_VALUE (\ + MX25_ADCQ_CFG_YPLL_OFF | \ + MX25_ADCQ_CFG_XNUR_OFF | \ + MX25_ADCQ_CFG_XPUL_HIGH | \ + MX25_ADCQ_CFG_REFP_INT | \ + MX25_ADCQ_CFG_IN_XP | \ + MX25_ADCQ_CFG_REFN_NGND2 | \ + MX25_ADCQ_CFG_IGS) + +#define MX25_TOUCH_DETECT_VALUE (\ + MX25_ADCQ_CFG_YNLR | \ + MX25_ADCQ_CFG_YPLL_OFF | \ + MX25_ADCQ_CFG_XNUR_OFF | \ + MX25_ADCQ_CFG_XPUL_OFF | \ + MX25_ADCQ_CFG_REFP_INT | \ + MX25_ADCQ_CFG_IN_XP | \ + MX25_ADCQ_CFG_REFN_NGND2 | \ + MX25_ADCQ_CFG_PENIACK) + +static void imx25_setup_queue_cfgs(struct mx25_tcq_priv *priv, + unsigned int settling_time) +{ + u32 precharge_cfg = + MX25_PRECHARGE_VALUE | + MX25_ADCQ_CFG_SETTLING_TIME(settling_time); + u32 touch_detect_cfg = + MX25_TOUCH_DETECT_VALUE | + MX25_ADCQ_CFG_NOS(1) | + MX25_ADCQ_CFG_SETTLING_TIME(settling_time); + + regmap_write(priv->core_regs, MX25_TSC_TICR, precharge_cfg); + + /* PRECHARGE */ + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_PRECHARGE), + precharge_cfg); + + /* TOUCH_DETECT */ + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_TOUCH_DETECT), + touch_detect_cfg); + + /* X Measurement */ + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_X_MEASUREMENT), + MX25_ADCQ_CFG_YPLL_OFF | + MX25_ADCQ_CFG_XNUR_LOW | + MX25_ADCQ_CFG_XPUL_HIGH | + MX25_ADCQ_CFG_REFP_XP | + MX25_ADCQ_CFG_IN_YP | + MX25_ADCQ_CFG_REFN_XN | + MX25_ADCQ_CFG_NOS(priv->sample_count) | + MX25_ADCQ_CFG_SETTLING_TIME(settling_time)); + + /* Y Measurement */ + regmap_write(priv->regs, MX25_ADCQ_CFG(MX25_CFG_Y_MEASUREMENT), + MX25_ADCQ_CFG_YNLR | + MX25_ADCQ_CFG_YPLL_HIGH | + MX25_ADCQ_CFG_XNUR_OFF | + MX25_ADCQ_CFG_XPUL_OFF | + MX25_ADCQ_CFG_REFP_YP | + MX25_ADCQ_CFG_IN_XP | + MX25_ADCQ_CFG_REFN_YN | + MX25_ADCQ_CFG_NOS(priv->sample_count) | + MX25_ADCQ_CFG_SETTLING_TIME(settling_time)); + + /* Enable the touch detection right now */ + regmap_write(priv->core_regs, MX25_TSC_TICR, touch_detect_cfg | + MX25_ADCQ_CFG_IGS); +} + +static int imx25_setup_queue_4wire(struct mx25_tcq_priv *priv, + unsigned settling_time, int *items) +{ + imx25_setup_queue_cfgs(priv, settling_time); + + /* Setup the conversion queue */ + regmap_write(priv->regs, MX25_ADCQ_ITEM_7_0, + MX25_ADCQ_ITEM(0, MX25_CFG_PRECHARGE) | + MX25_ADCQ_ITEM(1, MX25_CFG_TOUCH_DETECT) | + MX25_ADCQ_ITEM(2, MX25_CFG_X_MEASUREMENT) | + MX25_ADCQ_ITEM(3, MX25_CFG_Y_MEASUREMENT) | + MX25_ADCQ_ITEM(4, MX25_CFG_PRECHARGE) | + MX25_ADCQ_ITEM(5, MX25_CFG_TOUCH_DETECT)); + + /* We measure X/Y with 'sample_count' number of samples and execute a + * touch detection twice, with 1 sample each */ + priv->expected_samples = priv->sample_count * 2 + 2; + *items = 6; + + return 0; +} + +static void mx25_tcq_disable_touch_irq(struct mx25_tcq_priv *priv) +{ + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_PDMSK, + MX25_ADCQ_CR_PDMSK); +} + +static void mx25_tcq_enable_touch_irq(struct mx25_tcq_priv *priv) +{ + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_PDMSK, 0); +} + +static void mx25_tcq_disable_fifo_irq(struct mx25_tcq_priv *priv) +{ + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_FDRY_IRQ, + MX25_ADCQ_MR_FDRY_IRQ); +} + +static void mx25_tcq_enable_fifo_irq(struct mx25_tcq_priv *priv) +{ + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_FDRY_IRQ, 0); +} + +static void mx25_tcq_force_queue_start(struct mx25_tcq_priv *priv) +{ + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, + MX25_ADCQ_CR_FQS); + + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0); +} + +static void mx25_tcq_force_queue_stop(struct mx25_tcq_priv *priv) +{ + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FQS, 0); +} + +static void mx25_tcq_fifo_reset(struct mx25_tcq_priv *priv) +{ + u32 tcqcr; + + regmap_read(priv->regs, MX25_ADCQ_CR, &tcqcr); + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FRST, + MX25_ADCQ_CR_FRST); + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_FRST, + 0); + regmap_write(priv->regs, MX25_ADCQ_CR, tcqcr); +} + +static void mx25_tcq_re_enable_touch_detection(struct mx25_tcq_priv *priv) +{ + /* stop the queue from looping */ + mx25_tcq_force_queue_stop(priv); + + /* for a clean touch detection, preload the X plane */ + regmap_write(priv->core_regs, MX25_TSC_TICR, MX25_PRECHARGE_VALUE); + + /* waste some time now to pre-load the X plate to high voltage */ + mx25_tcq_fifo_reset(priv); + + /* re-enable the detection right now */ + regmap_write(priv->core_regs, MX25_TSC_TICR, MX25_TOUCH_DETECT_VALUE | + MX25_ADCQ_CFG_IGS); + + regmap_update_bits(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_PD, + MX25_ADCQ_SR_PD); + + /* enable the pen down event to be a source for the interrupt */ + regmap_update_bits(priv->regs, MX25_ADCQ_MR, MX25_ADCQ_MR_PD_IRQ, 0); + + /* lets fire the next IRQ if someone touches the touchscreen */ + mx25_tcq_enable_touch_irq(priv); +} + +static int mx25_tcq_create_event_for_4wire(struct mx25_tcq_priv *priv, + u32 *sample_buf, int samples) +{ + unsigned int x_pos = 0; + unsigned int y_pos = 0; + unsigned int touch_pre = 0; + unsigned int touch_post = 0; + unsigned i; + int ret = 0; + + for (i = 0; i < samples; i++) { + unsigned int index = MX25_ADCQ_FIFO_ID(sample_buf[i]); + unsigned int val = MX25_ADCQ_FIFO_DATA(sample_buf[i]); + + switch (index) { + case 1: + touch_pre = val; + break; + case 2: + x_pos = val; + break; + case 3: + y_pos = val; + break; + case 5: + touch_post = val; + break; + default: + ret = -EINVAL; + break; + } + } + + if (ret == 0 && samples != 0) { + /* + * only if both touch measures are below a treshold, + * the position is valid + */ + if (touch_pre < priv->pen_threshold && + touch_post < priv->pen_threshold) { + /* valid samples, generate a report */ + x_pos /= priv->sample_count; + y_pos /= priv->sample_count; + input_report_abs(priv->idev, ABS_X, x_pos); + input_report_abs(priv->idev, ABS_Y, y_pos); + input_report_key(priv->idev, BTN_TOUCH, + 0xfff - ((touch_pre + touch_post) / 2)); + input_sync(priv->idev); + + /* get next sample */ + mx25_tcq_force_queue_start(priv); + mx25_tcq_enable_fifo_irq(priv); + } else if (touch_pre >= priv->pen_threshold && + touch_post >= priv->pen_threshold) { + /* + * if both samples are invalid, + * generate a release report + */ + input_report_key(priv->idev, BTN_TOUCH, 0); + input_sync(priv->idev); + mx25_tcq_re_enable_touch_detection(priv); + } else { + /* + * if only one of both touch measurements are + * below the threshold, still some bouncing + * happens. Take additional samples in this + * case to be sure + */ + mx25_tcq_force_queue_start(priv); + mx25_tcq_enable_fifo_irq(priv); + } + } + + return ret; +} + +static irqreturn_t mx25_tcq_irq_thread(int irq, void *dev_id) +{ + struct mx25_tcq_priv *priv = (struct mx25_tcq_priv *) dev_id; + u32 sample_buf[TSC_MAX_SAMPLES]; + int samples = 0; + + /* read all samples */ + while (1) { + u32 stats; + + regmap_read(priv->regs, MX25_ADCQ_SR, &stats); + if (stats & MX25_ADCQ_SR_EMPT) + break; + + if (samples < TSC_MAX_SAMPLES) { + regmap_read(priv->regs, MX25_ADCQ_FIFO, + &sample_buf[samples]); + ++samples; + } else { + u32 discarded; + /* discard samples */ + regmap_read(priv->regs, MX25_ADCQ_FIFO, &discarded); + } + } + + mx25_tcq_create_event_for_4wire(priv, sample_buf, samples); + + return IRQ_HANDLED; +} + +static irqreturn_t mx25_tcq_irq(int irq, void *dev_id) +{ + struct mx25_tcq_priv *priv = (struct mx25_tcq_priv *)dev_id; + u32 stat; + int ret = IRQ_HANDLED; + + regmap_read(priv->regs, MX25_ADCQ_SR, &stat); + + if (stat & (MX25_ADCQ_SR_FRR | MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR)) + mx25_tcq_fifo_reset(priv); + + if (stat & MX25_ADCQ_SR_PD) { + mx25_tcq_disable_touch_irq(priv); + mx25_tcq_force_queue_start(priv); + mx25_tcq_enable_fifo_irq(priv); + } + + if (stat & MX25_ADCQ_SR_FDRY) { + mx25_tcq_disable_fifo_irq(priv); + ret = IRQ_WAKE_THREAD; + } + + regmap_update_bits(priv->regs, MX25_ADCQ_SR, MX25_ADCQ_SR_FRR | + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | MX25_ADCQ_SR_PD | + MX25_ADCQ_SR_EOQ, + MX25_ADCQ_SR_FRR | + MX25_ADCQ_SR_FUR | MX25_ADCQ_SR_FOR | MX25_ADCQ_SR_PD | + MX25_ADCQ_SR_EOQ); + + return ret; +} + +/* configure the statemachine for a 4-wire touchscreen */ +static int mx25_tcq_init(struct mx25_tcq_priv *priv) +{ + u32 tgcr; + unsigned int ipg_div; + unsigned int adc_period; + unsigned int debounce_cnt; + unsigned int settling_time; + int itemct; + int ret; + + regmap_read(priv->core_regs, MX25_TSC_TGCR, &tgcr); + ipg_div = max_t(unsigned int, 4, MX25_TGCR_GET_ADCCLK(tgcr)); + adc_period = clk_get_rate(priv->clk) / (ipg_div * 2 + 2); + debounce_cnt = DIV_ROUND_UP(priv->pen_debounce, adc_period * 8) - 1; + settling_time = DIV_ROUND_UP(priv->settling_time, adc_period); + + + /* Reset */ + regmap_write(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QRST | + MX25_ADCQ_CR_FRST); + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QRST | + MX25_ADCQ_CR_FRST, 0); + + /* up to 128 * 8 ADC clocks are possible */ + if (debounce_cnt > 127) + debounce_cnt = 127; + + ret = imx25_setup_queue_4wire(priv, 0x0, &itemct); + if (ret) + return ret; + + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_LITEMID_MASK | + MX25_ADCQ_CR_WMRK_MASK, + MX25_ADCQ_CR_LITEMID(itemct - 1) | + MX25_ADCQ_CR_WMRK(priv->expected_samples - 1)); + + /* setup debounce count */ + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, + MX25_TGCR_PDBTIME_MASK, + MX25_TGCR_PDBTIME(debounce_cnt)); + + /* enable debounce */ + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, MX25_TGCR_PDBEN, + MX25_TGCR_PDBEN); + regmap_update_bits(priv->core_regs, MX25_TSC_TGCR, MX25_TGCR_PDEN, + MX25_TGCR_PDEN); + + /* enable the engine on demand */ + regmap_update_bits(priv->regs, MX25_ADCQ_CR, MX25_ADCQ_CR_QSM_FQS, + MX25_ADCQ_CR_QSM_FQS); + + mx25_tcq_re_enable_touch_detection(priv); + + return 0; +} + +static int mx25_tcq_parse_dt(struct platform_device *pdev, + struct mx25_tcq_priv *priv) +{ + struct device_node *np = pdev->dev.of_node; + u32 wires; + int ret; + + /* Setup defaults */ + priv->pen_threshold = 500; + priv->sample_count = 3; + priv->pen_debounce = 1000000; + priv->settling_time = 250000; + + ret = of_property_read_u32(np, "fsl,wires", &wires); + if (ret) { + dev_err(&pdev->dev, "Failed to find fsl,wires properties\n"); + return ret; + } + + if (wires == 4) { + priv->mode = MX25_TS_4WIRE; + } else { + dev_err(&pdev->dev, "%u-wire mode not supported\n", wires); + return -EINVAL; + } + + /* These are optional, we don't care about the return values */ + of_property_read_u32(np, "fsl,pen-threshold", &priv->pen_threshold); + of_property_read_u32(np, "fsl,settling-time", &priv->settling_time); + of_property_read_u32(np, "fsl,pen-debounce", &priv->pen_debounce); + + return 0; +} + +static int mx25_tcq_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct input_dev *idev; + struct mx25_tcq_priv *priv; + struct resource *res; + void __iomem *mem; + int ret; + int irq; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + mem = devm_ioremap_resource(dev, res); + if (!mem) + return -ENOMEM; + + ret = mx25_tcq_parse_dt(pdev, priv); + if (ret) + return ret; + + priv->regs = devm_regmap_init_mmio(dev, mem, &mx25_tcq_regconfig); + if (IS_ERR(priv->regs)) { + dev_err(dev, "Failed to initialize regmap\n"); + return PTR_ERR(priv->regs); + } + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) { + dev_err(dev, "Failed to get IRQ\n"); + return irq; + } + + idev = devm_input_allocate_device(dev); + if (!idev) { + dev_err(dev, "Failed to allocate input device\n"); + return -ENOMEM; + } + + idev->name = mx25_tcq_name; + idev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + input_set_abs_params(idev, ABS_X, 0, 0xfff, 0, 0); + input_set_abs_params(idev, ABS_Y, 0, 0xfff, 0, 0); + + idev->id.bustype = BUS_HOST; + + ret = input_register_device(idev); + if (ret) { + dev_err(dev, "Failed to register input device\n"); + return ret; + } + + priv->idev = idev; + + priv->core_regs = mx25_tsadc_get_regmap(pdev->dev.parent); + priv->clk = mx25_tsadc_get_ipg(pdev->dev.parent); + + ret = clk_prepare_enable(priv->clk); + if (ret) { + dev_err(dev, "Failed to enable ipg clock\n"); + return ret; + } + + ret = devm_request_threaded_irq(dev, irq, mx25_tcq_irq, + mx25_tcq_irq_thread, IRQF_ONESHOT, pdev->name, priv); + if (ret) { + dev_err(dev, "Failed requesting IRQ\n"); + return ret; + } + + ret = mx25_tcq_init(priv); + if (ret) { + dev_err(dev, "Failed to init tcq\n"); + goto error_tcq_init; + } + + platform_set_drvdata(pdev, priv); + + return 0; + +error_tcq_init: + clk_disable_unprepare(priv->clk); + return ret; +} + +static int mx25_tcq_remove(struct platform_device *pdev) +{ + struct mx25_tcq_priv *priv = platform_get_drvdata(pdev); + + clk_disable_unprepare(priv->clk); + + return 0; +} + +static struct platform_driver mx25_tcq_driver = { + .driver = { + .name = "mx25-tcq", + .owner = THIS_MODULE, + .of_match_table = mx25_tcq_ids, + }, + .probe = mx25_tcq_probe, + .remove = mx25_tcq_remove, +}; +module_platform_driver(mx25_tcq_driver); + +MODULE_DESCRIPTION("TS input driver for Freescale mx25"); +MODULE_AUTHOR("Markus Pargmann <mpa@pengutronix.de>"); +MODULE_LICENSE("GPL v2");