Re: [PATCH v2] Input: pixcir_i2c_ts - Add RESET gpio

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




Hi Dmitry,

On 02/06/15 12:33, Roger Quadros wrote:
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@xxxxxx>

Could you please pick this up for v4.3? Thanks.

cheers,
-roger

---
  .../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;
  };

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]
  Powered by Linux