| Message ID | 1459357049-5608-1-git-send-email-bjorn.andersson@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Bjorn, On Wed, Mar 30, 2016 at 09:57:29AM -0700, Bjorn Andersson wrote: > From: Bjorn Andersson <bjorn.andersson@sonymobile.com> > > Support the two supplies - vdd and vio - to make it possible to control > power to the Synaptics chip. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 7 ++++ > drivers/input/rmi4/rmi_i2c.c | 45 ++++++++++++++++++++++ Would not we need pretty much the same changes for SPI devices? Can this be done in core? Thanks. > 2 files changed, 52 insertions(+) > > diff --git a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt > index 95fa715c6046..a8c31f40f816 100644 > --- a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt > +++ b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt > @@ -22,6 +22,13 @@ See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt > - syna,reset-delay-ms: The number of milliseconds to wait after resetting the > device. > > +- vdd-supply: VDD power supply. > +See Documentation/devicetree/bindings/regulator/regulator.txt > + > +- vio-supply: VIO power supply > +See Documentation/devicetree/bindings/regulator/regulator.txt > + > + > Function Parameters: > Parameters specific to RMI functions are contained in child nodes of the rmi device > node. Documentation for the parameters of each function can be found in: > diff --git a/drivers/input/rmi4/rmi_i2c.c b/drivers/input/rmi4/rmi_i2c.c > index a96a326b53bd..a8c794daba04 100644 > --- a/drivers/input/rmi4/rmi_i2c.c > +++ b/drivers/input/rmi4/rmi_i2c.c > @@ -11,6 +11,8 @@ > #include <linux/rmi.h> > #include <linux/irq.h> > #include <linux/of.h> > +#include <linux/delay.h> > +#include <linux/regulator/consumer.h> > #include "rmi_driver.h" > > #define BUFFER_SIZE_INCREMENT 32 > @@ -37,6 +39,8 @@ struct rmi_i2c_xport { > > u8 *tx_buf; > size_t tx_buf_size; > + > + struct regulator_bulk_data supplies[2]; > }; > > #define RMI_PAGE_SELECT_REGISTER 0xff > @@ -246,6 +250,22 @@ static int rmi_i2c_probe(struct i2c_client *client, > return -ENODEV; > } > > + rmi_i2c->supplies[0].supply = "vdd"; > + rmi_i2c->supplies[1].supply = "vio"; > + retval = devm_regulator_bulk_get(&client->dev, > + ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > + if (retval < 0) > + return retval; > + > + retval = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > + if (retval < 0) > + return retval; > + > + /* Allow the firmware to get ready */ > + msleep(10); > + > rmi_i2c->client = client; > mutex_init(&rmi_i2c->page_mutex); > > @@ -286,6 +306,8 @@ static int rmi_i2c_remove(struct i2c_client *client) > struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); > > rmi_unregister_transport_device(&rmi_i2c->xport); > + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > > return 0; > } > @@ -308,6 +330,10 @@ static int rmi_i2c_suspend(struct device *dev) > dev_warn(dev, "Failed to enable irq for wake: %d\n", > ret); > } > + > + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > + > return ret; > } > > @@ -317,6 +343,14 @@ static int rmi_i2c_resume(struct device *dev) > struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); > int ret; > > + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > + if (ret) > + return ret; > + > + /* Allow the firmware to get ready */ > + msleep(10); > + > enable_irq(rmi_i2c->irq); > if (device_may_wakeup(&client->dev)) { > ret = disable_irq_wake(rmi_i2c->irq); > @@ -346,6 +380,9 @@ static int rmi_i2c_runtime_suspend(struct device *dev) > > disable_irq(rmi_i2c->irq); > > + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > + > return 0; > } > > @@ -355,6 +392,14 @@ static int rmi_i2c_runtime_resume(struct device *dev) > struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); > int ret; > > + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), > + rmi_i2c->supplies); > + if (ret) > + return ret; > + > + /* Allow the firmware to get ready */ > + msleep(10); > + > enable_irq(rmi_i2c->irq); > > ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev); > -- > 2.5.0 >
On Thu 31 Mar 11:19 PDT 2016, Dmitry Torokhov wrote: > Hi Bjorn, > > On Wed, Mar 30, 2016 at 09:57:29AM -0700, Bjorn Andersson wrote: > > From: Bjorn Andersson <bjorn.andersson@sonymobile.com> > > > > Support the two supplies - vdd and vio - to make it possible to control > > power to the Synaptics chip. > > > > Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> > > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > > --- > > .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 7 ++++ > > drivers/input/rmi4/rmi_i2c.c | 45 ++++++++++++++++++++++ > > Would not we need pretty much the same changes for SPI devices? Can this > be done in core? > Yes, I believe it needs the exact same steps. I did a initial quick hack on v1 of the patchset and back then it was possible, when I rebased it a few weeks back I kept ending up in getting interrupts with the power off. Looking at the code this is likely because in the resume paths the IRQ is enabled before we jump to rmi_driver_resume(), so putting this in the core I ended up calling rmi_process_interrupt_requests() before powering up the chip. I assume it's done this way to allow incoming interrupts while functions are being resumed. Andrew, can you comment on this? Regards, Bjorn > Thanks. > > > 2 files changed, 52 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt > > index 95fa715c6046..a8c31f40f816 100644 > > --- a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt > > +++ b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt > > @@ -22,6 +22,13 @@ See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt > > - syna,reset-delay-ms: The number of milliseconds to wait after resetting the > > device. > > > > +- vdd-supply: VDD power supply. > > +See Documentation/devicetree/bindings/regulator/regulator.txt > > + > > +- vio-supply: VIO power supply > > +See Documentation/devicetree/bindings/regulator/regulator.txt > > + > > + > > Function Parameters: > > Parameters specific to RMI functions are contained in child nodes of the rmi device > > node. Documentation for the parameters of each function can be found in: > > diff --git a/drivers/input/rmi4/rmi_i2c.c b/drivers/input/rmi4/rmi_i2c.c > > index a96a326b53bd..a8c794daba04 100644 > > --- a/drivers/input/rmi4/rmi_i2c.c > > +++ b/drivers/input/rmi4/rmi_i2c.c > > @@ -11,6 +11,8 @@ > > #include <linux/rmi.h> > > #include <linux/irq.h> > > #include <linux/of.h> > > +#include <linux/delay.h> > > +#include <linux/regulator/consumer.h> > > #include "rmi_driver.h" > > > > #define BUFFER_SIZE_INCREMENT 32 > > @@ -37,6 +39,8 @@ struct rmi_i2c_xport { > > > > u8 *tx_buf; > > size_t tx_buf_size; > > + > > + struct regulator_bulk_data supplies[2]; > > }; > > > > #define RMI_PAGE_SELECT_REGISTER 0xff > > @@ -246,6 +250,22 @@ static int rmi_i2c_probe(struct i2c_client *client, > > return -ENODEV; > > } > > > > + rmi_i2c->supplies[0].supply = "vdd"; > > + rmi_i2c->supplies[1].supply = "vio"; > > + retval = devm_regulator_bulk_get(&client->dev, > > + ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > + if (retval < 0) > > + return retval; > > + > > + retval = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > + if (retval < 0) > > + return retval; > > + > > + /* Allow the firmware to get ready */ > > + msleep(10); > > + > > rmi_i2c->client = client; > > mutex_init(&rmi_i2c->page_mutex); > > > > @@ -286,6 +306,8 @@ static int rmi_i2c_remove(struct i2c_client *client) > > struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); > > > > rmi_unregister_transport_device(&rmi_i2c->xport); > > + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > > > return 0; > > } > > @@ -308,6 +330,10 @@ static int rmi_i2c_suspend(struct device *dev) > > dev_warn(dev, "Failed to enable irq for wake: %d\n", > > ret); > > } > > + > > + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > + > > return ret; > > } > > > > @@ -317,6 +343,14 @@ static int rmi_i2c_resume(struct device *dev) > > struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); > > int ret; > > > > + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > + if (ret) > > + return ret; > > + > > + /* Allow the firmware to get ready */ > > + msleep(10); > > + > > enable_irq(rmi_i2c->irq); > > if (device_may_wakeup(&client->dev)) { > > ret = disable_irq_wake(rmi_i2c->irq); > > @@ -346,6 +380,9 @@ static int rmi_i2c_runtime_suspend(struct device *dev) > > > > disable_irq(rmi_i2c->irq); > > > > + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > + > > return 0; > > } > > > > @@ -355,6 +392,14 @@ static int rmi_i2c_runtime_resume(struct device *dev) > > struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); > > int ret; > > > > + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), > > + rmi_i2c->supplies); > > + if (ret) > > + return ret; > > + > > + /* Allow the firmware to get ready */ > > + msleep(10); > > + > > enable_irq(rmi_i2c->irq); > > > > ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev); > > -- > > 2.5.0 > > > > -- > Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 03/31/2016 12:14 PM, Bjorn Andersson wrote: > On Thu 31 Mar 11:19 PDT 2016, Dmitry Torokhov wrote: > >> Hi Bjorn, >> >> On Wed, Mar 30, 2016 at 09:57:29AM -0700, Bjorn Andersson wrote: >>> From: Bjorn Andersson <bjorn.andersson@sonymobile.com> >>> >>> Support the two supplies - vdd and vio - to make it possible to control >>> power to the Synaptics chip. >>> >>> Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> >>> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> >>> --- >>> .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 7 ++++ >>> drivers/input/rmi4/rmi_i2c.c | 45 ++++++++++++++++++++++ >> Would not we need pretty much the same changes for SPI devices? Can this >> be done in core? >> > Yes, I believe it needs the exact same steps. > > I did a initial quick hack on v1 of the patchset and back then it was > possible, when I rebased it a few weeks back I kept ending up in getting > interrupts with the power off. > > Looking at the code this is likely because in the resume paths the IRQ > is enabled before we jump to rmi_driver_resume(), so putting this in the > core I ended up calling rmi_process_interrupt_requests() before powering > up the chip. Actually, I don't think the irq needs to be enabled before calling rmi_driver_resume(). Typically, the functions are just reading and writing to registers and do not need to handle interrupts. We could probably call to rmi_driver_resume() before enabling the irq. I can double check that there are not any exceptions to this. I have also considered adding a power callback to the core so that the transport drivers can set the power independently of suspend and resume. One example would be to shut off power to a touchpad if a mouse is connected. If we do need to have the irq enabled before calling rmi_driver_resume() we could still move regulator support to the core and call the power callback from the transport drivers. Andrew > I assume it's done this way to allow incoming interrupts while functions > are being resumed. Andrew, can you comment on this? > > Regards, > Bjorn > >> Thanks. >> >>> 2 files changed, 52 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt >>> index 95fa715c6046..a8c31f40f816 100644 >>> --- a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt >>> +++ b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt >>> @@ -22,6 +22,13 @@ See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt >>> - syna,reset-delay-ms: The number of milliseconds to wait after resetting the >>> device. >>> >>> +- vdd-supply: VDD power supply. >>> +See Documentation/devicetree/bindings/regulator/regulator.txt >>> + >>> +- vio-supply: VIO power supply >>> +See Documentation/devicetree/bindings/regulator/regulator.txt >>> + >>> + >>> Function Parameters: >>> Parameters specific to RMI functions are contained in child nodes of the rmi device >>> node. Documentation for the parameters of each function can be found in: >>> diff --git a/drivers/input/rmi4/rmi_i2c.c b/drivers/input/rmi4/rmi_i2c.c >>> index a96a326b53bd..a8c794daba04 100644 >>> --- a/drivers/input/rmi4/rmi_i2c.c >>> +++ b/drivers/input/rmi4/rmi_i2c.c >>> @@ -11,6 +11,8 @@ >>> #include <linux/rmi.h> >>> #include <linux/irq.h> >>> #include <linux/of.h> >>> +#include <linux/delay.h> >>> +#include <linux/regulator/consumer.h> >>> #include "rmi_driver.h" >>> >>> #define BUFFER_SIZE_INCREMENT 32 >>> @@ -37,6 +39,8 @@ struct rmi_i2c_xport { >>> >>> u8 *tx_buf; >>> size_t tx_buf_size; >>> + >>> + struct regulator_bulk_data supplies[2]; >>> }; >>> >>> #define RMI_PAGE_SELECT_REGISTER 0xff >>> @@ -246,6 +250,22 @@ static int rmi_i2c_probe(struct i2c_client *client, >>> return -ENODEV; >>> } >>> >>> + rmi_i2c->supplies[0].supply = "vdd"; >>> + rmi_i2c->supplies[1].supply = "vio"; >>> + retval = devm_regulator_bulk_get(&client->dev, >>> + ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> + if (retval < 0) >>> + return retval; >>> + >>> + retval = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> + if (retval < 0) >>> + return retval; >>> + >>> + /* Allow the firmware to get ready */ >>> + msleep(10); >>> + >>> rmi_i2c->client = client; >>> mutex_init(&rmi_i2c->page_mutex); >>> >>> @@ -286,6 +306,8 @@ static int rmi_i2c_remove(struct i2c_client *client) >>> struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); >>> >>> rmi_unregister_transport_device(&rmi_i2c->xport); >>> + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> >>> return 0; >>> } >>> @@ -308,6 +330,10 @@ static int rmi_i2c_suspend(struct device *dev) >>> dev_warn(dev, "Failed to enable irq for wake: %d\n", >>> ret); >>> } >>> + >>> + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> + >>> return ret; >>> } >>> >>> @@ -317,6 +343,14 @@ static int rmi_i2c_resume(struct device *dev) >>> struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); >>> int ret; >>> >>> + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> + if (ret) >>> + return ret; >>> + >>> + /* Allow the firmware to get ready */ >>> + msleep(10); >>> + >>> enable_irq(rmi_i2c->irq); >>> if (device_may_wakeup(&client->dev)) { >>> ret = disable_irq_wake(rmi_i2c->irq); >>> @@ -346,6 +380,9 @@ static int rmi_i2c_runtime_suspend(struct device *dev) >>> >>> disable_irq(rmi_i2c->irq); >>> >>> + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> + >>> return 0; >>> } >>> >>> @@ -355,6 +392,14 @@ static int rmi_i2c_runtime_resume(struct device *dev) >>> struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); >>> int ret; >>> >>> + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), >>> + rmi_i2c->supplies); >>> + if (ret) >>> + return ret; >>> + >>> + /* Allow the firmware to get ready */ >>> + msleep(10); >>> + >>> enable_irq(rmi_i2c->irq); >>> >>> ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev); >>> -- >>> 2.5.0 >>> >> -- >> Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu 31 Mar 18:47 PDT 2016, Andrew Duggan wrote: > On 03/31/2016 12:14 PM, Bjorn Andersson wrote: > >On Thu 31 Mar 11:19 PDT 2016, Dmitry Torokhov wrote: > > > >>Hi Bjorn, > >> > >>On Wed, Mar 30, 2016 at 09:57:29AM -0700, Bjorn Andersson wrote: > >>>From: Bjorn Andersson <bjorn.andersson@sonymobile.com> > >>> > >>>Support the two supplies - vdd and vio - to make it possible to control > >>>power to the Synaptics chip. > >>> > >>>Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> > >>>Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > >>>--- > >>> .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 7 ++++ > >>> drivers/input/rmi4/rmi_i2c.c | 45 ++++++++++++++++++++++ > >>Would not we need pretty much the same changes for SPI devices? Can this > >>be done in core? > >> > >Yes, I believe it needs the exact same steps. > > > >I did a initial quick hack on v1 of the patchset and back then it was > >possible, when I rebased it a few weeks back I kept ending up in getting > >interrupts with the power off. > > > >Looking at the code this is likely because in the resume paths the IRQ > >is enabled before we jump to rmi_driver_resume(), so putting this in the > >core I ended up calling rmi_process_interrupt_requests() before powering > >up the chip. > > Actually, I don't think the irq needs to be enabled before calling > rmi_driver_resume(). Typically, the functions are just reading and writing > to registers and do not need to handle interrupts. We could probably call to > rmi_driver_resume() before enabling the irq. I can double check that there > are not any exceptions to this. > I finally got back to giving this a spin. The problem is that we register the transport device with the driver, which triggers the rmi_driver probe() which resolves the resources. We then continue on and call rmi_i2c_init_irq() which will (implicitly) enable the irq. So if the rmi_driver probe() does not finish in a serial fashion we will enable interrupts before we have fully initialized the core. I don't know if this causes other issues, but with the required delay after enabling the regulators we always get an interrupt before the rmi_driver probe() function is finished. > I have also considered adding a power callback to the core so that the > transport drivers can set the power independently of suspend and resume. One > example would be to shut off power to a touchpad if a mouse is connected. If > we do need to have the irq enabled before calling rmi_driver_resume() we > could still move regulator support to the core and call the power callback > from the transport drivers. > I see no (sane) way of waiting for the rmi_driver to finish probeing; there could be cases where it's powered by a regulator (or reset gpio) that is not yet probed. EPROBE_DEFER will handle this, but we can't wait for it in the transport driver. I therefor think these physical resources should be handled in the context of the transport layer, to make sure we don't have temporal dependencies to the other layers. Or we should not have the rmi_driver as a separate device driver at all - it could be a "library" that runs in the context of the transport device. Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Bjorn, On 04/21/2016 03:37 PM, Bjorn Andersson wrote: > On Thu 31 Mar 18:47 PDT 2016, Andrew Duggan wrote: > >> On 03/31/2016 12:14 PM, Bjorn Andersson wrote: >>> On Thu 31 Mar 11:19 PDT 2016, Dmitry Torokhov wrote: >>> >>>> Hi Bjorn, >>>> >>>> On Wed, Mar 30, 2016 at 09:57:29AM -0700, Bjorn Andersson wrote: >>>>> From: Bjorn Andersson <bjorn.andersson@sonymobile.com> >>>>> >>>>> Support the two supplies - vdd and vio - to make it possible to control >>>>> power to the Synaptics chip. >>>>> >>>>> Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> >>>>> Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> >>>>> --- >>>>> .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 7 ++++ >>>>> drivers/input/rmi4/rmi_i2c.c | 45 ++++++++++++++++++++++ >>>> Would not we need pretty much the same changes for SPI devices? Can this >>>> be done in core? >>>> >>> Yes, I believe it needs the exact same steps. >>> >>> I did a initial quick hack on v1 of the patchset and back then it was >>> possible, when I rebased it a few weeks back I kept ending up in getting >>> interrupts with the power off. >>> >>> Looking at the code this is likely because in the resume paths the IRQ >>> is enabled before we jump to rmi_driver_resume(), so putting this in the >>> core I ended up calling rmi_process_interrupt_requests() before powering >>> up the chip. >> Actually, I don't think the irq needs to be enabled before calling >> rmi_driver_resume(). Typically, the functions are just reading and writing >> to registers and do not need to handle interrupts. We could probably call to >> rmi_driver_resume() before enabling the irq. I can double check that there >> are not any exceptions to this. >> > I finally got back to giving this a spin. > > The problem is that we register the transport device with the driver, > which triggers the rmi_driver probe() which resolves the resources. We > then continue on and call rmi_i2c_init_irq() which will (implicitly) > enable the irq. So if the rmi_driver probe() does not finish in a serial > fashion we will enable interrupts before we have fully initialized the > core. > > I don't know if this causes other issues, but with the required delay > after enabling the regulators we always get an interrupt before the > rmi_driver probe() function is finished. I have not observed any issues related to timing, but it looks like on the systems which I have tested on rmi_driver() seems to be completing synchronously before the init_irq() call. I was making the assumption that rmi_driver() would have completed by the time rmi_register_transport_device() returned. But, based on your description and looking into the base driver code I see that the probe can be deferred and that assumption isn't always true. >> I have also considered adding a power callback to the core so that the >> transport drivers can set the power independently of suspend and resume. One >> example would be to shut off power to a touchpad if a mouse is connected. If >> we do need to have the irq enabled before calling rmi_driver_resume() we >> could still move regulator support to the core and call the power callback >> from the transport drivers. >> > I see no (sane) way of waiting for the rmi_driver to finish probeing; > there could be cases where it's powered by a regulator (or reset gpio) > that is not yet probed. EPROBE_DEFER will handle this, but we can't wait > for it in the transport driver. Do we need to wait for rmi_driver to finish probing? What about setting a flag at the end of rmi_driver_probe() which rmi_process_interrupt_requests() can check before processing interrupts. If rmi_driver hasn't finished probing it could just return. > > I therefor think these physical resources should be handled in the > context of the transport layer, to make sure we don't have temporal > dependencies to the other layers. I'm fine with enabling the regulators in the transport driver's probe function before calling rmi_register_transport_device() to make sure the device is powered on. What about exporting common functions from rmi_driver.c which implement common regulator functionality which can then be called by the transports? To avoid duplication between rmi_i2c and rmi_spi. > Or we should not have the rmi_driver as a separate device driver at all > - it could be a "library" that runs in the context of the transport > device. I would have to look into this further to understand the impact on the bus architecture of merging the physical and transport drivers. But, I don't think this particular issue warrants such a change. But, if having them as separate devices does cause a lot of other problems, it might be possible to merge them. Andrew > Regards, > Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu 05 May 13:55 PDT 2016, Andrew Duggan wrote: > Hi Bjorn, > > On 04/21/2016 03:37 PM, Bjorn Andersson wrote: [..] > >I see no (sane) way of waiting for the rmi_driver to finish probeing; > >there could be cases where it's powered by a regulator (or reset gpio) > >that is not yet probed. EPROBE_DEFER will handle this, but we can't wait > >for it in the transport driver. > > Do we need to wait for rmi_driver to finish probing? What about setting a > flag at the end of rmi_driver_probe() which rmi_process_interrupt_requests() > can check before processing interrupts. If rmi_driver hasn't finished > probing it could just return. > Note that the required resources could be provided by a kernel module that is loaded at some future time, or never. So we can't really stall the transport probe(). > > > >I therefor think these physical resources should be handled in the > >context of the transport layer, to make sure we don't have temporal > >dependencies to the other layers. > > I'm fine with enabling the regulators in the transport driver's probe > function before calling rmi_register_transport_device() to make sure the > device is powered on. What about exporting common functions from > rmi_driver.c which implement common regulator functionality which can then > be called by the transports? To avoid duplication between rmi_i2c and > rmi_spi. > For the DT binding documents I think it's best to just duplicate the information, as long as we don't see more common properties between a growing number of transports (unlikely). For the implementation we need a context to operate on before probing the common code, as far as I can see the two places are per transport or in struct rmi_transport_dev. The latter would allow us to provide a few common helper functions. That part that I can see would make it worth adding this is the delay (Tpowerup?), especially if we need to do something more advanced here. I've found various numbers of Tpowerup (10ms to 150ms) and some implementations out there leave the regulators on during sleep, while others cut the power. So it seems we will be up for some level of additional logic here, that warrants the de-duplication. > >Or we should not have the rmi_driver as a separate device driver at all > >- it could be a "library" that runs in the context of the transport > >device. > > I would have to look into this further to understand the impact on the bus > architecture of merging the physical and transport drivers. But, I don't > think this particular issue warrants such a change. But, if having them as > separate devices does cause a lot of other problems, it might be possible > to merge them. > I get the feeling that there is an expected 1:1 relationship between the transport and core driver, making the use of the driver model for separation overkill and a potential cause of issues. I agree this might not warrant the churn of a rewrite, but I'm concern about the above helpers just working around an artificial issue. Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
The first version of the regulator support patch suffered from being implemented in the transport driver, as a work around for resource availability racing (EPROBE_DEFER of the core driver) with the interrupt handler. After reconsidering the solutions discussed following that I concluded that the interrupt management is not really part of the transport, neither conceptually or electrically. I therefor here suggest (patch 1/3) to move the interrupt registration and handling to the core rmi driver. This solves the potential race of interrupts being delivered in the transport driver before the core driver have been given a chance to recover from probe deferral. Patch 2/3 then add the necessary code for acquiring regulator handles and enabling these. Patch 3/3 removes the set_page() done in the transport drivers, as we can't rely on the chip becoming available at any time during the initialization/probe phase. Bjorn Andersson (3): input: rmi4: Move IRQ handling to rmi_driver input: rmi4: Acquire and enable VDD and VIO supplies input: rmi4: Remove set_page() call before core is initialized .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 6 ++ .../devicetree/bindings/input/rmi4/rmi_spi.txt | 6 ++ drivers/input/rmi4/rmi_driver.c | 89 +++++++++++++++++++++- drivers/input/rmi4/rmi_i2c.c | 84 ++------------------ drivers/input/rmi4/rmi_spi.c | 83 ++------------------ include/linux/rmi.h | 11 ++- 6 files changed, 118 insertions(+), 161 deletions(-)
Hi Bjorn, On 05/06/2016 09:40 PM, Bjorn Andersson wrote: > The first version of the regulator support patch suffered from being > implemented in the transport driver, as a work around for resource availability > racing (EPROBE_DEFER of the core driver) with the interrupt handler. > > After reconsidering the solutions discussed following that I concluded that the > interrupt management is not really part of the transport, neither conceptually > or electrically. I therefor here suggest (patch 1/3) to move the interrupt > registration and handling to the core rmi driver. My concern with moving interrupt processing to the core is that not all transports report attn to the rmi core using an irq. The HID and SMBus transports which are currently in development, reside a little higher in the stack and attention is reported using different mechanisms. We moved interrupt handling to the transport drivers so that they could handle the differences in how attn is reported. This message has some of the previous discussion regarding interrupt processing: https://lkml.org/lkml/2015/11/28/123 Similarly, not all transports will need support for regulators. Implementing both in the transport drivers avoids the EPROBE_DEFER racing and avoids adding checks in the core to see if it needs to handle interrupts and manage regulators. Thanks, Andrew > This solves the potential race of interrupts being delivered in the transport > driver before the core driver have been given a chance to recover from probe > deferral. > > Patch 2/3 then add the necessary code for acquiring regulator handles and > enabling these. > > Patch 3/3 removes the set_page() done in the transport drivers, as we can't > rely on the chip becoming available at any time during the initialization/probe > phase. > > Bjorn Andersson (3): > input: rmi4: Move IRQ handling to rmi_driver > input: rmi4: Acquire and enable VDD and VIO supplies > input: rmi4: Remove set_page() call before core is initialized > > .../devicetree/bindings/input/rmi4/rmi_i2c.txt | 6 ++ > .../devicetree/bindings/input/rmi4/rmi_spi.txt | 6 ++ > drivers/input/rmi4/rmi_driver.c | 89 +++++++++++++++++++++- > drivers/input/rmi4/rmi_i2c.c | 84 ++------------------ > drivers/input/rmi4/rmi_spi.c | 83 ++------------------ > include/linux/rmi.h | 11 ++- > 6 files changed, 118 insertions(+), 161 deletions(-) > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon 09 May 17:36 PDT 2016, Andrew Duggan wrote: > Hi Bjorn, > > On 05/06/2016 09:40 PM, Bjorn Andersson wrote: > >The first version of the regulator support patch suffered from being > >implemented in the transport driver, as a work around for resource availability > >racing (EPROBE_DEFER of the core driver) with the interrupt handler. > > > >After reconsidering the solutions discussed following that I concluded that the > >interrupt management is not really part of the transport, neither conceptually > >or electrically. I therefor here suggest (patch 1/3) to move the interrupt > >registration and handling to the core rmi driver. > > My concern with moving interrupt processing to the core is that not all > transports report attn to the rmi core using an irq. The HID and SMBus > transports which are currently in development, reside a little higher in the > stack and attention is reported using different mechanisms. We moved > interrupt handling to the transport drivers so that they could handle the > differences in how attn is reported. > I suspected that to be the case. > This message has some of the previous discussion regarding interrupt > processing: > https://lkml.org/lkml/2015/11/28/123 > > Similarly, not all transports will need support for regulators. Implementing > both in the transport drivers avoids the EPROBE_DEFER racing and avoids > adding checks in the core to see if it needs to handle interrupts and manage > regulators. > So either we duplicate the regulator support in spi/i2c or we make them optional in the core driver. Sounds like you prefer the prior, i.e. v1 of my patch. Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hi Bjorn, On 05/10/2016 08:49 AM, Bjorn Andersson wrote: > On Mon 09 May 17:36 PDT 2016, Andrew Duggan wrote: > >> Hi Bjorn, >> >> On 05/06/2016 09:40 PM, Bjorn Andersson wrote: >>> The first version of the regulator support patch suffered from being >>> implemented in the transport driver, as a work around for resource availability >>> racing (EPROBE_DEFER of the core driver) with the interrupt handler. >>> >>> After reconsidering the solutions discussed following that I concluded that the >>> interrupt management is not really part of the transport, neither conceptually >>> or electrically. I therefor here suggest (patch 1/3) to move the interrupt >>> registration and handling to the core rmi driver. >> My concern with moving interrupt processing to the core is that not all >> transports report attn to the rmi core using an irq. The HID and SMBus >> transports which are currently in development, reside a little higher in the >> stack and attention is reported using different mechanisms. We moved >> interrupt handling to the transport drivers so that they could handle the >> differences in how attn is reported. >> > I suspected that to be the case. > >> This message has some of the previous discussion regarding interrupt >> processing: >> https://lkml.org/lkml/2015/11/28/123 >> >> Similarly, not all transports will need support for regulators. Implementing >> both in the transport drivers avoids the EPROBE_DEFER racing and avoids >> adding checks in the core to see if it needs to handle interrupts and manage >> regulators. >> > So either we duplicate the regulator support in spi/i2c or we make them > optional in the core driver. Sounds like you prefer the prior, i.e. v1 > of my patch. Yes, after all this I think it makes sense to put regulator support in the spi/i2c transports like in your v1 patch. I essentially duplicated the irq handling code in both transports so I would be ok with duplicating regulator support too. It doesn't seem like that much code. But, if this is too much duplication we could create some sort of common file and put the common irq and regulator support functions which could be called in the transports. Similar to how rmi_2d_sensor.c defines some common functions shared between rmi_f11 and rmi_f12. Thanks, Andrew > Regards, > Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed 11 May 16:30 PDT 2016, Andrew Duggan wrote: > Hi Bjorn, > > On 05/10/2016 08:49 AM, Bjorn Andersson wrote: [..] > >So either we duplicate the regulator support in spi/i2c or we make them > >optional in the core driver. Sounds like you prefer the prior, i.e. v1 > >of my patch. > > Yes, after all this I think it makes sense to put regulator support in the > spi/i2c transports like in your v1 patch. I essentially duplicated the irq > handling code in both transports so I would be ok with duplicating regulator > support too. It doesn't seem like that much code. But, if this is too much > duplication we could create some sort of common file and put the common irq > and regulator support functions which could be called in the transports. > Similar to how rmi_2d_sensor.c defines some common functions shared between > rmi_f11 and rmi_f12. > Sounds reasonable, I'm okay with this. Did you have any comments on the implementation I had in v1? @Dmitry, do you want me to resend v1? Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/11/2016 08:05 PM, Bjorn Andersson wrote: > On Wed 11 May 16:30 PDT 2016, Andrew Duggan wrote: > >> Hi Bjorn, >> >> On 05/10/2016 08:49 AM, Bjorn Andersson wrote: > [..] >>> So either we duplicate the regulator support in spi/i2c or we make them >>> optional in the core driver. Sounds like you prefer the prior, i.e. v1 >>> of my patch. >> Yes, after all this I think it makes sense to put regulator support in the >> spi/i2c transports like in your v1 patch. I essentially duplicated the irq >> handling code in both transports so I would be ok with duplicating regulator >> support too. It doesn't seem like that much code. But, if this is too much >> duplication we could create some sort of common file and put the common irq >> and regulator support functions which could be called in the transports. >> Similar to how rmi_2d_sensor.c defines some common functions shared between >> rmi_f11 and rmi_f12. >> > Sounds reasonable, I'm okay with this. Did you have any comments on the > implementation I had in v1? I tested on a device which has an always on regulators so I didn't add anything to device tree for the device. But, it returned 0 when it didn't find anything which seems to be the correct behavior. Is there an easy way to avoid sleeping for 10ms when there are no regulators? Maybe check if both the supplies .consumer pointer is null? Andrew > @Dmitry, do you want me to resend v1? > > Regards, > Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu 12 May 17:52 PDT 2016, Andrew Duggan wrote: > On 05/11/2016 08:05 PM, Bjorn Andersson wrote: > >On Wed 11 May 16:30 PDT 2016, Andrew Duggan wrote: > > > >>Hi Bjorn, > >> > >>On 05/10/2016 08:49 AM, Bjorn Andersson wrote: > >[..] > >>>So either we duplicate the regulator support in spi/i2c or we make them > >>>optional in the core driver. Sounds like you prefer the prior, i.e. v1 > >>>of my patch. > >>Yes, after all this I think it makes sense to put regulator support in the > >>spi/i2c transports like in your v1 patch. I essentially duplicated the irq > >>handling code in both transports so I would be ok with duplicating regulator > >>support too. It doesn't seem like that much code. But, if this is too much > >>duplication we could create some sort of common file and put the common irq > >>and regulator support functions which could be called in the transports. > >>Similar to how rmi_2d_sensor.c defines some common functions shared between > >>rmi_f11 and rmi_f12. > >> > >Sounds reasonable, I'm okay with this. Did you have any comments on the > >implementation I had in v1? > > I tested on a device which has an always on regulators so I didn't add > anything to device tree for the device. But, it returned 0 when it didn't > find anything which seems to be the correct behavior. Is there an easy way > to avoid sleeping for 10ms when there are no regulators? Maybe check if both > the supplies .consumer pointer is null? > I did look at this as well, but unfortunately the regulators does not come back as NULL, but rather as dummy regulators. The delay matches Tpowerup (iirc) from the data sheet, which I assume is firmware/hardware dependant. Should we provide a knob for that and default the sleep to 0ms? Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/13/2016 03:29 PM, Bjorn Andersson wrote: > On Thu 12 May 17:52 PDT 2016, Andrew Duggan wrote: > >> On 05/11/2016 08:05 PM, Bjorn Andersson wrote: >>> On Wed 11 May 16:30 PDT 2016, Andrew Duggan wrote: >>> >>>> Hi Bjorn, >>>> >>>> On 05/10/2016 08:49 AM, Bjorn Andersson wrote: >>> [..] >>>>> So either we duplicate the regulator support in spi/i2c or we make them >>>>> optional in the core driver. Sounds like you prefer the prior, i.e. v1 >>>>> of my patch. >>>> Yes, after all this I think it makes sense to put regulator support in the >>>> spi/i2c transports like in your v1 patch. I essentially duplicated the irq >>>> handling code in both transports so I would be ok with duplicating regulator >>>> support too. It doesn't seem like that much code. But, if this is too much >>>> duplication we could create some sort of common file and put the common irq >>>> and regulator support functions which could be called in the transports. >>>> Similar to how rmi_2d_sensor.c defines some common functions shared between >>>> rmi_f11 and rmi_f12. >>>> >>> Sounds reasonable, I'm okay with this. Did you have any comments on the >>> implementation I had in v1? >> I tested on a device which has an always on regulators so I didn't add >> anything to device tree for the device. But, it returned 0 when it didn't >> find anything which seems to be the correct behavior. Is there an easy way >> to avoid sleeping for 10ms when there are no regulators? Maybe check if both >> the supplies .consumer pointer is null? >> > I did look at this as well, but unfortunately the regulators does not > come back as NULL, but rather as dummy regulators. > > The delay matches Tpowerup (iirc) from the data sheet, which I assume is > firmware/hardware dependant. Should we provide a knob for that and > default the sleep to 0ms? Making the default 0 and then setting an appropriate time out for devices which need it sounds like a good idea to me. Thanks, Andrew > Regards, > Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt index 95fa715c6046..a8c31f40f816 100644 --- a/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt +++ b/Documentation/devicetree/bindings/input/rmi4/rmi_i2c.txt @@ -22,6 +22,13 @@ See Documentation/devicetree/bindings/interrupt-controller/interrupts.txt - syna,reset-delay-ms: The number of milliseconds to wait after resetting the device. +- vdd-supply: VDD power supply. +See Documentation/devicetree/bindings/regulator/regulator.txt + +- vio-supply: VIO power supply +See Documentation/devicetree/bindings/regulator/regulator.txt + + Function Parameters: Parameters specific to RMI functions are contained in child nodes of the rmi device node. Documentation for the parameters of each function can be found in: diff --git a/drivers/input/rmi4/rmi_i2c.c b/drivers/input/rmi4/rmi_i2c.c index a96a326b53bd..a8c794daba04 100644 --- a/drivers/input/rmi4/rmi_i2c.c +++ b/drivers/input/rmi4/rmi_i2c.c @@ -11,6 +11,8 @@ #include <linux/rmi.h> #include <linux/irq.h> #include <linux/of.h> +#include <linux/delay.h> +#include <linux/regulator/consumer.h> #include "rmi_driver.h" #define BUFFER_SIZE_INCREMENT 32 @@ -37,6 +39,8 @@ struct rmi_i2c_xport { u8 *tx_buf; size_t tx_buf_size; + + struct regulator_bulk_data supplies[2]; }; #define RMI_PAGE_SELECT_REGISTER 0xff @@ -246,6 +250,22 @@ static int rmi_i2c_probe(struct i2c_client *client, return -ENODEV; } + rmi_i2c->supplies[0].supply = "vdd"; + rmi_i2c->supplies[1].supply = "vio"; + retval = devm_regulator_bulk_get(&client->dev, + ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); + if (retval < 0) + return retval; + + retval = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); + if (retval < 0) + return retval; + + /* Allow the firmware to get ready */ + msleep(10); + rmi_i2c->client = client; mutex_init(&rmi_i2c->page_mutex); @@ -286,6 +306,8 @@ static int rmi_i2c_remove(struct i2c_client *client) struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); rmi_unregister_transport_device(&rmi_i2c->xport); + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); return 0; } @@ -308,6 +330,10 @@ static int rmi_i2c_suspend(struct device *dev) dev_warn(dev, "Failed to enable irq for wake: %d\n", ret); } + + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); + return ret; } @@ -317,6 +343,14 @@ static int rmi_i2c_resume(struct device *dev) struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); int ret; + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); + if (ret) + return ret; + + /* Allow the firmware to get ready */ + msleep(10); + enable_irq(rmi_i2c->irq); if (device_may_wakeup(&client->dev)) { ret = disable_irq_wake(rmi_i2c->irq); @@ -346,6 +380,9 @@ static int rmi_i2c_runtime_suspend(struct device *dev) disable_irq(rmi_i2c->irq); + regulator_bulk_disable(ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); + return 0; } @@ -355,6 +392,14 @@ static int rmi_i2c_runtime_resume(struct device *dev) struct rmi_i2c_xport *rmi_i2c = i2c_get_clientdata(client); int ret; + ret = regulator_bulk_enable(ARRAY_SIZE(rmi_i2c->supplies), + rmi_i2c->supplies); + if (ret) + return ret; + + /* Allow the firmware to get ready */ + msleep(10); + enable_irq(rmi_i2c->irq); ret = rmi_driver_resume(rmi_i2c->xport.rmi_dev);