[PATCH v2 1/2] Input: edt-ft5x06 - Add support for regulator

Dmitry Torokhov
2018-01-22T17:42:08Z

Hi Myl?ne,

On Thu, Dec 28, 2017 at 8:33 AM, Myl?ne Josserand
<mylene.josserand@free-electrons.com> wrote:
> Add the support of regulator to use it as VCC source.
>
> Signed-off-by: Myl?ne Josserand <mylene.josserand@free-electrons.com>
> ---
> .../bindings/input/touchscreen/edt-ft5x06.txt | 1 +
> drivers/input/touchscreen/edt-ft5x06.c | 33 ++++++++++++++++++++++
> 2 files changed, 34 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 c53a3d7239e7..5ee14a25a382 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;
> @@ -993,6 +995,23 @@ 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);
> + dev_err(&client->dev, "failed to request regulator: %d\n",
> + error);
> + return error;
> + };

As 0-day pounted out, this semicolon is not needed.

> +
> + if (tsdata->vcc) {

You do not need to check for non-NULL here, devm_regulator_get() wil
lnever give you a NULL. If regulator is not defined in DT/board
mappings, then dummy regulator will be provided. You can call
regulator_enable() and regulator_disable() and other regulator APIs
with dummy regulator.

> + 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)) {
> @@ -1122,20 +1141,34 @@ 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);
>
> + if (tsdata->vcc)

Same here.

> + regulator_disable(tsdata->vcc);
> +
> return 0;
> }
>
> static int __maybe_unused edt_ft5x06_ts_resume(struct device *dev)
> {
> struct i2c_client *client = to_i2c_client(dev);
> + struct edt_ft5x06_ts_data *tsdata = i2c_get_clientdata(client);
> + int ret;
>
> if (device_may_wakeup(dev))
> disable_irq_wake(client->irq);
>
> + if (tsdata->vcc) {

And here.

> + ret = regulator_enable(tsdata->vcc);
> + if (ret < 0) {
> + dev_err(dev, "failed to enable vcc: %d\n", ret);
> + return ret;
> + }

Since power to the device may have been cut, I think you need to
restore the register settings to whatever it was (factory vs work
mode, threshold, gain and offset registers, etc, etc).

> + }
> +
> return 0;
> }
>
> --
> 2.11.0
>

Thanks.

--
Dmitry