On Thu, Jul 19, 2018 at 12:46:45AM +0200, Ondřej Jirman wrote:
> Hello Mylène,
>
> On Wed, Jul 18, 2018 at 08:27:17PM +0200, Mylène Josserand wrote:
> > Add the support of regulator to use it as VCC source.
> >
> > Signed-off-by: Mylène Josserand <mylene.josser...@bootlin.com>
> > ---
> > .../bindings/input/touchscreen/edt-ft5x06.txt | 1 +
> > drivers/input/touchscreen/edt-ft5x06.c | 29
> > ++++++++++++++++++++++
> > 2 files changed, 30 insertions(+)
> >
> > diff --git
> > a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> > b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> > index 025cf8c9324a..48e975b9c1aa 100644
> > --- a/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> > +++ b/Documentation/devicetree/bindings/input/touchscreen/edt-ft5x06.txt
> > @@ -30,6 +30,7 @@ Required properties:
> > Optional properties:
> > - reset-gpios: GPIO specification for the RESET input
> > - wake-gpios: GPIO specification for the WAKE input
> > + - vcc-supply: Regulator that supplies the touchscreen
> >
> > - pinctrl-names: should be "default"
> > - pinctrl-0: a phandle pointing to the pin settings for the
> > diff --git a/drivers/input/touchscreen/edt-ft5x06.c
> > b/drivers/input/touchscreen/edt-ft5x06.c
> > index 1e18ca0d1b4e..aa94494b06b5 100644
> > --- a/drivers/input/touchscreen/edt-ft5x06.c
> > +++ b/drivers/input/touchscreen/edt-ft5x06.c
> > @@ -39,6 +39,7 @@
> > #include <linux/input/mt.h>
> > #include <linux/input/touchscreen.h>
> > #include <linux/of_device.h>
> > +#include <linux/regulator/consumer.h>
> >
> > #define WORK_REGISTER_THRESHOLD 0x00
> > #define WORK_REGISTER_REPORT_RATE 0x08
> > @@ -91,6 +92,7 @@ struct edt_ft5x06_ts_data {
> > struct touchscreen_properties prop;
> > u16 num_x;
> > u16 num_y;
> > + struct regulator *vcc;
> >
> > struct gpio_desc *reset_gpio;
> > struct gpio_desc *wake_gpio;
> > @@ -991,6 +993,22 @@ static int edt_ft5x06_ts_probe(struct i2c_client
> > *client,
> >
> > tsdata->max_support_points = chip_data->max_support_points;
> >
> > + tsdata->vcc = devm_regulator_get(&client->dev, "vcc");
> > + if (IS_ERR(tsdata->vcc)) {
> > + error = PTR_ERR(tsdata->vcc);
> > + if (error != -EPROBE_DEFER)
> > + dev_err(&client->dev, "failed to request regulator:
> > %d\n",
> > + error);
> > + return error;
> > + }
> > +
> > + error = regulator_enable(tsdata->vcc);
> > + if (error < 0) {
> > + dev_err(&client->dev, "failed to enable vcc: %d\n",
> > + error);
> > + return error;
> > + }
> > +
> > tsdata->reset_gpio = devm_gpiod_get_optional(&client->dev,
> > "reset", GPIOD_OUT_HIGH);
> > if (IS_ERR(tsdata->reset_gpio)) {
You need to disable regulator here. We do not have
devm_regulator_enable() (and Mark had some concerns about mixing managed
and unmanaged APIs for regulators so we can't simply introduce it),
so I'd recommend using devm_add_action_or_reset() and iunstall custom
action to turn off regulator.
> > @@ -1120,20 +1138,31 @@ static int edt_ft5x06_ts_remove(struct i2c_client
> > *client)
> > static int __maybe_unused edt_ft5x06_ts_suspend(struct device *dev)
> > {
> > struct i2c_client *client = to_i2c_client(dev);
> > + struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
> >
> > if (device_may_wakeup(dev))
> > enable_irq_wake(client->irq);
> >
> > + regulator_disable(tsdata->vcc);
> > +
>
> How will the touchscreen wakeup the system with interrupt if you power it off
> on suspend? Perhaps guard this with device_may_wakeup() too?
Exactly, it should be in an "else" branch.
Thanks.
--
Dmitry
