[PATCH v2 4/7] touchscreen: pixcir_i2c: Add support for wake and enable gpios
Dmitry Torokhov
dmitry.torokhov at gmail.com
Fri Nov 20 11:32:14 PST 2015
On Fri, Nov 20, 2015 at 08:19:52PM +0100, Hans de Goede wrote:
> Hi,
>
> On 20-11-15 19:54, Dmitry Torokhov wrote:
> >On Fri, Nov 20, 2015 at 02:24:49PM +0100, Hans de Goede wrote:
> >>From: Sander Vermin <sander at vermin.nl>
> >>
> >>On some devices the wake and enable pins of the pixcir touchscreen
> >>controller are connected to gpios and these must be controlled by the
> >>driver for the device to operate properly.
> >>
> >>Signed-off-by: Sander Vermin <sander at vermin.nl>
> >>Signed-off-by: Hans de Goede <hdegoede at redhat.com>
> >>---
> >>Changes in v2 (Hans de Goede):
> >>-Split the changes for dealing with inverted / swapped axis out into a
> >> separate patch
> >>-Remove a bunch of dev_info calls to make the driver less chatty
> >>-Use devm_gpiod_get_optional as these new gpios are optional
> >>-Only msleep after setting enable high if we have an enable pin
> >>---
> >> .../bindings/input/touchscreen/pixcir_i2c_ts.txt | 2 +
> >> drivers/input/touchscreen/pixcir_i2c_ts.c | 46 ++++++++++++++++++++++
> >> 2 files changed, 48 insertions(+)
> >>
> >>diff --git a/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt b/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt
> >>index 8eb240a..72ca5ec 100644
> >>--- a/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt
> >>+++ b/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt
> >>@@ -10,6 +10,8 @@ Required properties:
> >>
> >> Optional properties:
> >> - reset-gpio: GPIO connected to the RESET line of the chip
> >>+- enable-gpios: GPIO connected to the ENABLE line of the chip
> >>+- wake-gpios: GPIO connected to the WAKE line of the chip
> >>
> >> Example:
> >>
> >>diff --git a/drivers/input/touchscreen/pixcir_i2c_ts.c b/drivers/input/touchscreen/pixcir_i2c_ts.c
> >>index 211408c..b75ef65 100644
> >>--- a/drivers/input/touchscreen/pixcir_i2c_ts.c
> >>+++ b/drivers/input/touchscreen/pixcir_i2c_ts.c
> >>@@ -38,6 +38,8 @@ struct pixcir_i2c_ts_data {
> >> struct input_dev *input;
> >> struct gpio_desc *gpio_attb;
> >> struct gpio_desc *gpio_reset;
> >>+ struct gpio_desc *gpio_enable;
> >>+ struct gpio_desc *gpio_wake;
> >> const struct pixcir_i2c_chip_data *chip;
> >> int max_fingers; /* Max fingers supported in this instance */
> >> bool running;
> >>@@ -208,6 +210,11 @@ static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
> >> struct device *dev = &ts->client->dev;
> >> int ret;
> >>
> >>+ if (mode == PIXCIR_POWER_ACTIVE || mode == PIXCIR_POWER_IDLE) {
> >>+ if (!IS_ERR_OR_NULL(ts->gpio_wake))
> >>+ gpiod_set_value_cansleep(ts->gpio_wake, 1);
> >>+ }
> >>+
> >> ret = i2c_smbus_read_byte_data(ts->client, PIXCIR_REG_POWER_MODE);
> >> if (ret < 0) {
> >> dev_err(dev, "%s: can't read reg 0x%x : %d\n",
> >>@@ -228,6 +235,11 @@ static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts,
> >> return ret;
> >> }
> >>
> >>+ if (mode == PIXCIR_POWER_HALT) {
> >>+ if (!IS_ERR_OR_NULL(ts->gpio_wake))
> >>+ gpiod_set_value_cansleep(ts->gpio_wake, 0);
> >>+ }
> >>+
> >> return 0;
> >> }
> >>
> >>@@ -302,6 +314,11 @@ static int pixcir_start(struct pixcir_i2c_ts_data *ts)
> >> struct device *dev = &ts->client->dev;
> >> int error;
> >>
> >>+ if (!IS_ERR_OR_NULL(ts->gpio_enable)) {
> >>+ gpiod_set_value_cansleep(ts->gpio_enable, 1);
> >>+ msleep(100);
> >>+ }
> >>+
> >> /* LEVEL_TOUCH interrupt with active low polarity */
> >> error = pixcir_set_int_mode(ts, PIXCIR_INT_LEVEL_TOUCH, 0);
> >> if (error) {
> >>@@ -343,6 +360,9 @@ static int pixcir_stop(struct pixcir_i2c_ts_data *ts)
> >> /* Wait till running ISR is complete */
> >> synchronize_irq(ts->client->irq);
> >>
> >>+ if (!IS_ERR_OR_NULL(ts->gpio_enable))
> >>+ gpiod_set_value_cansleep(ts->gpio_enable, 0);
> >>+
> >> return 0;
> >> }
> >>
> >>@@ -534,6 +554,24 @@ static int pixcir_i2c_ts_probe(struct i2c_client *client,
> >> return error;
> >> }
> >>
> >>+ tsdata->gpio_wake = devm_gpiod_get_optional(dev, "wake",
> >>+ GPIOD_OUT_HIGH);
> >>+ if (IS_ERR(tsdata->gpio_wake)) {
> >>+ error = PTR_ERR(tsdata->gpio_wake);
> >>+ if (error != -EPROBE_DEFER)
> >>+ dev_err(dev, "Failed to get wake gpio: %d\n", error);
> >>+ return error;
> >>+ }
> >>+
> >>+ tsdata->gpio_enable = devm_gpiod_get_optional(dev, "enable",
> >>+ GPIOD_OUT_HIGH);
> >>+ if (IS_ERR(tsdata->gpio_enable)) {
> >>+ error = PTR_ERR(tsdata->gpio_enable);
> >>+ if (error != -EPROBE_DEFER)
> >>+ dev_err(dev, "Failed to get enable gpio: %d\n", error);
> >>+ return error;
> >>+ }
> >>+
> >> error = devm_request_threaded_irq(dev, client->irq, NULL, pixcir_ts_isr,
> >> IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
> >> client->name, tsdata);
> >>@@ -542,6 +580,14 @@ static int pixcir_i2c_ts_probe(struct i2c_client *client,
> >> return error;
> >> }
> >>
> >>+ if (!IS_ERR_OR_NULL(tsdata->gpio_wake))
> >>+ gpiod_set_value_cansleep(tsdata->gpio_wake, 1);
> >>+
> >>+ if (!IS_ERR_OR_NULL(tsdata->gpio_enable)) {
> >>+ gpiod_set_value_cansleep(tsdata->gpio_enable, 1);
> >>+ msleep(100);
> >>+ }
> >
> >Actually, another question: why do we need this calls to activate wake
> >and enable gpios here if we request them as active?
>
> Hmm, interesting point. I will re-test with just the msleep there. For v2
> what do you want to do with the if tests, keep as "if (!IS_ERR_OR_NULL(...))"
> or change them to just "if (...)" ?
Would prefer plain "if (gpio)" where makes sense.
Thanks!
--
Dmitry
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