Re: [PATCH 1/3] drivers/gpio: devres.c: allow gpio array requests for managed devices

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

 




On 18/06/14 14:24, Heiko Stübner wrote:
Am Dienstag, 10. Juni 2014, 15:41:46 schrieb Rob Jones:
Add functions devm_gpio_request_array() and devm_gpio_free_array()
which are exactly analogous to the equivalent non-managed device
functions gpio_request_array() and gpio_free_array(), which can be
found in module gpiolib.c.

Note that if devm_gpio_request_array() fails, no gpios are obtained.
No indication is provided as to which particular request failed.

Reviewed-by: Ian Molton <ian.molton@xxxxxxxxxxxxxxx>
Signed-off-by: Rob Jones <rob.jones@xxxxxxxxxxxxxxx>
apart from the doc issue below this looks ok to me


---
  drivers/gpio/devres.c |   57
+++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/gpio.h  |
  4 ++++
  2 files changed, 61 insertions(+)

diff --git a/drivers/gpio/devres.c b/drivers/gpio/devres.c
index 307464f..fd95240d 100644
--- a/drivers/gpio/devres.c
+++ b/drivers/gpio/devres.c
@@ -186,6 +186,63 @@ int devm_gpio_request_one(struct device *dev, unsigned
gpio, EXPORT_SYMBOL(devm_gpio_request_one);

  /**
+ * devm_gpio_request_array - request multiple GPIOs in a single call
+ *			     for a managed device
+ * @dev:	device requesting the gpio
+ * @array:      array of the 'struct gpio'
+ * @num:        how many GPIOs in the array
@dev uses a tab as spacing, while @array and @num use spaces, might be nice to
have this consistent.

I'm not sure how that happened. I'll rework it before re-submitting the series.



+ *
+ * Except for the extra @dev argument, this function takes the
+ * same arguments and performs the same function as
+ * gpio_request().  GPIOs requested with this function will be
+ * automatically freed on driver detach.
+ *
+ * If GPIOs allocated with this function need to be freed separately,
+ * devm_gpio_free_array() or devm_gpio_free() must be used.
+ */
+int devm_gpio_request_array(struct device *dev,
+			    const struct gpio *array,
+			    size_t num)
+{
+	int i, err = 0;
+
+	for (i = 0; i < num; i++, array++) {
+		err = devm_gpio_request_one(dev,
+					    array->gpio,
+					    array->flags,
+					    array->label);
+		if (err) {
+			while (i--)
+				devm_gpio_free(dev, (--array)->gpio);
+		}
+	}
+
+	return err;
+}
+EXPORT_SYMBOL(devm_gpio_request_array);
+
+/**
+ * devm_gpio_free_array - release multiple GPIOs in a single call
+ *			  for a managed device
+ * @dev:	device requesting the gpio
+ * @array:      array of the 'struct gpio'
+ * @num:        how many GPIOs in the array
same here

+ *
+ * Except for the extra @dev argument, this function takes the
+ * same arguments and performs the same function as gpio_free_array().
+ * This function instead of gpio_free_array() should be used to
+ * manually free GPIOs allocated with devm_gpio_request().
+ */
+void devm_gpio_free_array(struct device *dev,
+			  const struct gpio *array,
+			  size_t num)
+{
+	while (num--)
+		devm_gpio_free(dev, (array++)->gpio);
+}
+EXPORT_SYMBOL(devm_gpio_free_array);
+
+/**
   *      devm_gpio_free - free a GPIO
   *      @dev: device to free GPIO for
   *      @gpio: GPIO to free
diff --git a/include/linux/gpio.h b/include/linux/gpio.h
index 85aa5d0..12d5648 100644
--- a/include/linux/gpio.h
+++ b/include/linux/gpio.h
@@ -84,6 +84,10 @@ struct device;
  int devm_gpio_request(struct device *dev, unsigned gpio, const char
*label); int devm_gpio_request_one(struct device *dev, unsigned gpio,
  			  unsigned long flags, const char *label);
+int devm_gpio_request_array(struct device *dev, const struct gpio *array,
+			    size_t num);
+void devm_gpio_free_array(struct device *dev, const struct gpio *array,
+			 size_t num);
  void devm_gpio_free(struct device *dev, unsigned int gpio);

  #else /* ! CONFIG_GPIOLIB */



--
Rob Jones
Project Manager
Codethink Ltd
mailto:rob.jones@xxxxxxxxxxxxxxx
tel:+44 161 236 5575

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




[Index of Archives]     [Linux SPI]     [Linux Kernel]     [Linux ARM (vger)]     [Linux ARM MSM]     [Linux Omap]     [Linux Arm]     [Linux Tegra]     [Fedora ARM]     [Linux for Samsung SOC]     [eCos]     [Linux Fastboot]     [Gcc Help]     [Git]     [DCCP]     [IETF Announce]     [Security]     [Linux MIPS]     [Yosemite Campsites]

  Powered by Linux