From: Roger Quadros <[email protected]> The controller has a RESET pin which is usually controlled over a GPIO line. If such a GPIO is provided, perform a RESET during probe.
Signed-off-by: Roger Quadros <[email protected]> Signed-off-by: Dmitry Torokhov <[email protected]> --- .../bindings/input/touchscreen/pixcir_i2c_ts.txt | 3 +++ drivers/input/touchscreen/pixcir_i2c_ts.c | 22 ++++++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt b/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt index 6e55109..8eb240a 100644 --- a/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt +++ b/Documentation/devicetree/bindings/input/touchscreen/pixcir_i2c_ts.txt @@ -8,6 +8,9 @@ Required properties: - touchscreen-size-x: horizontal resolution of touchscreen (in pixels) - touchscreen-size-y: vertical resolution of touchscreen (in pixels) +Optional properties: +- reset-gpio: GPIO connected to the RESET line of the chip + Example: i2c@00000000 { diff --git a/drivers/input/touchscreen/pixcir_i2c_ts.c b/drivers/input/touchscreen/pixcir_i2c_ts.c index 8965d7c..9d9ac08 100644 --- a/drivers/input/touchscreen/pixcir_i2c_ts.c +++ b/drivers/input/touchscreen/pixcir_i2c_ts.c @@ -36,6 +36,7 @@ struct pixcir_i2c_ts_data { struct i2c_client *client; struct input_dev *input; struct gpio_desc *gpio_attb; + struct gpio_desc *gpio_reset; const struct pixcir_ts_platform_data *pdata; bool running; int max_fingers; /* Max fingers supported in this instance */ @@ -189,6 +190,17 @@ static irqreturn_t pixcir_ts_isr(int irq, void *dev_id) return IRQ_HANDLED; } +static void pixcir_reset(struct pixcir_i2c_ts_data *tsdata) +{ + if (!IS_ERR_OR_NULL(tsdata->gpio_reset)) { + gpiod_set_value_cansleep(tsdata->gpio_reset, 1); + ndelay(100); /* datasheet section 1.2.3 says 80ns min. */ + gpiod_set_value_cansleep(tsdata->gpio_reset, 0); + /* wait for controller ready. 100ms guess. */ + msleep(100); + } +} + static int pixcir_set_power_mode(struct pixcir_i2c_ts_data *ts, enum pixcir_power_mode mode) { @@ -529,6 +541,14 @@ static int pixcir_i2c_ts_probe(struct i2c_client *client, return error; } + tsdata->gpio_reset = devm_gpiod_get_optional(dev, "reset", + GPIOD_OUT_LOW); + if (IS_ERR(tsdata->gpio_reset)) { + error = PTR_ERR(tsdata->gpio_reset); + dev_err(dev, "Failed to request RESET 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); @@ -537,6 +557,8 @@ static int pixcir_i2c_ts_probe(struct i2c_client *client, return error; } + pixcir_reset(tsdata); + /* Always be in IDLE mode to save power, device supports auto wake */ error = pixcir_set_power_mode(tsdata, PIXCIR_POWER_IDLE); if (error) { -- 2.4.3.573.g4eafbef -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
