Messages in this thread Patch in this message | | | Date | Tue, 2 Jun 2015 12:33:34 +0300 | From | Roger Quadros <> | Subject | [PATCH v2] Input: pixcir_i2c_ts - Add RESET gpio |
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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 <rogerq@ti.com> --- .../bindings/input/touchscreen/pixcir_i2c_ts.txt | 3 ++ drivers/input/touchscreen/pixcir_i2c_ts.c | 37 ++++++++++++++++++++-- include/linux/input/pixcir_ts.h | 1 + 3 files changed, 38 insertions(+), 3 deletions(-)
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 2c21071..80c956d 100644 --- a/drivers/input/touchscreen/pixcir_i2c_ts.c +++ b/drivers/input/touchscreen/pixcir_i2c_ts.c @@ -51,6 +51,19 @@ struct pixcir_report_data { struct pixcir_touch touches[PIXCIR_MAX_SLOTS]; }; +static void pixcir_reset(struct pixcir_i2c_ts_data *tsdata) +{ + const struct pixcir_ts_platform_data *pdata = tsdata->pdata; + + if (gpio_is_valid(pdata->gpio_reset)) { + gpio_set_value(pdata->gpio_reset, 1); + ndelay(100); /* datasheet section 1.2.3 says 80ns min. */ + gpio_set_value(pdata->gpio_reset, 0); + /* wait for controller ready. 100ms guess. */ + msleep(100); + } +} + static void pixcir_ts_parse(struct pixcir_i2c_ts_data *tsdata, struct pixcir_report_data *report) { @@ -428,7 +441,8 @@ static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev) pdata->chip = *(const struct pixcir_i2c_chip_data *)match->data; pdata->gpio_attb = of_get_named_gpio(np, "attb-gpio", 0); - /* gpio_attb validity is checked in probe */ + pdata->gpio_reset = of_get_named_gpio(np, "reset-gpio", 0); + /* gpio validity is checked in probe */ if (of_property_read_u32(np, "touchscreen-size-x", &pdata->x_max)) { dev_err(dev, "Failed to get touchscreen-size-x property\n"); @@ -442,8 +456,9 @@ static struct pixcir_ts_platform_data *pixcir_parse_dt(struct device *dev) } pdata->y_max -= 1; - dev_dbg(dev, "%s: x %d, y %d, gpio %d\n", __func__, - pdata->x_max + 1, pdata->y_max + 1, pdata->gpio_attb); + dev_dbg(dev, "%s: x %d, y %d, ATTB gpio %d, RESET gpio %d\n", __func__, + pdata->x_max + 1, pdata->y_max + 1, pdata->gpio_attb, + pdata->gpio_reset); return pdata; } @@ -481,6 +496,10 @@ static int pixcir_i2c_ts_probe(struct i2c_client *client, return -EINVAL; } + /* RESET gpio is optional */ + if (!gpio_is_valid(pdata->gpio_reset)) + dev_info(dev, "Invalid gpio_reset in pdata\n"); + if (!pdata->chip.max_fingers) { dev_err(dev, "Invalid max_fingers in pdata\n"); return -EINVAL; @@ -530,6 +549,16 @@ static int pixcir_i2c_ts_probe(struct i2c_client *client, input_set_drvdata(input, tsdata); + if (gpio_is_valid(pdata->gpio_reset)) { + error = devm_gpio_request_one(dev, pdata->gpio_reset, + GPIOF_OUT_INIT_LOW, + "pixcir_i2c_reset"); + if (error) { + dev_err(dev, "Failed to request RESET gpio\n"); + return error; + } + } + error = devm_gpio_request_one(dev, pdata->gpio_attb, GPIOF_DIR_IN, "pixcir_i2c_attb"); if (error) { @@ -545,6 +574,8 @@ 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) { diff --git a/include/linux/input/pixcir_ts.h b/include/linux/input/pixcir_ts.h index 7bae83b..5b204dd 100644 --- a/include/linux/input/pixcir_ts.h +++ b/include/linux/input/pixcir_ts.h @@ -58,6 +58,7 @@ struct pixcir_ts_platform_data { int x_max; int y_max; int gpio_attb; /* GPIO connected to ATTB line */ + int gpio_reset; /* GPIO to RESET line. Set to -1 if unused */ struct pixcir_i2c_chip_data chip; }; -- 2.1.4
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