Hello Dimitry,

Thank you for the review!

Le Mon, 22 Jan 2018 09:42:08 -0800,
Dmitry Torokhov [off-list ref] a ?crit :

Hi Myl?ne,

On Thu, Dec 28, 2017 at 8:33 AM, Myl?ne Josserand
[off-list ref] wrote:

quoted

Add the support of regulator to use it as VCC source.

Signed-off-by: Myl?ne Josserand <redacted>
---
 .../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.

Yes, thanks, I will fix that in next version.

quoted

+
+       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.

Okay, thanks for the explanation, I will remove that.

quoted

+               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.

yep

quoted

+               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.

yep

quoted

+               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).

Okay. Could you tell me how can I do that?

quoted

+       }
+
        return 0;
 }

--
2.11.0
 

Thanks.

About your V2's review, you suggested to add support for wake/reset in
suspend/resume (that I forgot in this version). I wanted to add it but
with my board, I can't test suspend/resume. What should I do about
that?

If I send a V3 in next few days, do you think you will have time to
merge it for v4.16?

Thank you in advance,

Best regards,

Myl?ne

-- 
Myl?ne Josserand, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com