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path: root/drivers/gpio/gpiolib.c
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Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c130
1 files changed, 77 insertions, 53 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index d407f904a31c..be74bd370f1f 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -20,6 +20,7 @@
#include <linux/cdev.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
+#include <linux/compat.h>
#include <uapi/linux/gpio.h>
#include "gpiolib.h"
@@ -316,7 +317,7 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct gpio_device *gdev = filp->private_data;
struct gpio_chip *chip = gdev->chip;
- int __user *ip = (int __user *)arg;
+ void __user *ip = (void __user *)arg;
/* We fail any subsequent ioctl():s when the chip is gone */
if (!chip)
@@ -388,6 +389,14 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return -EINVAL;
}
+#ifdef CONFIG_COMPAT
+static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
+ unsigned long arg)
+{
+ return gpio_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
/**
* gpio_chrdev_open() - open the chardev for ioctl operations
* @inode: inode for this chardev
@@ -431,14 +440,15 @@ static const struct file_operations gpio_fileops = {
.owner = THIS_MODULE,
.llseek = noop_llseek,
.unlocked_ioctl = gpio_ioctl,
- .compat_ioctl = gpio_ioctl,
+#ifdef CONFIG_COMPAT
+ .compat_ioctl = gpio_ioctl_compat,
+#endif
};
static void gpiodevice_release(struct device *dev)
{
struct gpio_device *gdev = dev_get_drvdata(dev);
- cdev_del(&gdev->chrdev);
list_del(&gdev->list);
ida_simple_remove(&gpio_ida, gdev->id);
kfree(gdev->label);
@@ -471,7 +481,6 @@ static int gpiochip_setup_dev(struct gpio_device *gdev)
/* From this point, the .release() function cleans up gpio_device */
gdev->dev.release = gpiodevice_release;
- get_device(&gdev->dev);
pr_debug("%s: registered GPIOs %d to %d on device: %s (%s)\n",
__func__, gdev->base, gdev->base + gdev->ngpio - 1,
dev_name(&gdev->dev), gdev->chip->label ? : "generic");
@@ -618,6 +627,8 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
goto err_free_label;
}
+ spin_unlock_irqrestore(&gpio_lock, flags);
+
for (i = 0; i < chip->ngpio; i++) {
struct gpio_desc *desc = &gdev->descs[i];
@@ -649,8 +660,6 @@ int gpiochip_add_data(struct gpio_chip *chip, void *data)
}
}
- spin_unlock_irqrestore(&gpio_lock, flags);
-
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&gdev->pin_ranges);
#endif
@@ -759,6 +768,8 @@ void gpiochip_remove(struct gpio_chip *chip)
* be removed, else it will be dangling until the last user is
* gone.
*/
+ cdev_del(&gdev->chrdev);
+ device_del(&gdev->dev);
put_device(&gdev->dev);
}
EXPORT_SYMBOL_GPL(gpiochip_remove);
@@ -858,7 +869,7 @@ struct gpio_chip *gpiochip_find(void *data,
spin_lock_irqsave(&gpio_lock, flags);
list_for_each_entry(gdev, &gpio_devices, list)
- if (match(gdev->chip, data))
+ if (gdev->chip && match(gdev->chip, data))
break;
/* No match? */
@@ -1341,14 +1352,6 @@ static int __gpiod_request(struct gpio_desc *desc, const char *label)
spin_lock_irqsave(&gpio_lock, flags);
}
done:
- if (status < 0) {
- /* Clear flags that might have been set by the caller before
- * requesting the GPIO.
- */
- clear_bit(FLAG_ACTIVE_LOW, &desc->flags);
- clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
- clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
- }
spin_unlock_irqrestore(&gpio_lock, flags);
return status;
}
@@ -1356,11 +1359,18 @@ done:
/*
* This descriptor validation needs to be inserted verbatim into each
* function taking a descriptor, so we need to use a preprocessor
- * macro to avoid endless duplication.
+ * macro to avoid endless duplication. If the desc is NULL it is an
+ * optional GPIO and calls should just bail out.
*/
#define VALIDATE_DESC(desc) do { \
- if (!desc || !desc->gdev) { \
- pr_warn("%s: invalid GPIO\n", __func__); \
+ if (!desc) \
+ return 0; \
+ if (IS_ERR(desc)) { \
+ pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
+ return PTR_ERR(desc); \
+ } \
+ if (!desc->gdev) { \
+ pr_warn("%s: invalid GPIO (no device)\n", __func__); \
return -EINVAL; \
} \
if ( !desc->gdev->chip ) { \
@@ -1370,8 +1380,14 @@ done:
} } while (0)
#define VALIDATE_DESC_VOID(desc) do { \
- if (!desc || !desc->gdev) { \
- pr_warn("%s: invalid GPIO\n", __func__); \
+ if (!desc) \
+ return; \
+ if (IS_ERR(desc)) { \
+ pr_warn("%s: invalid GPIO (errorpointer)\n", __func__); \
+ return; \
+ } \
+ if (!desc->gdev) { \
+ pr_warn("%s: invalid GPIO (no device)\n", __func__); \
return; \
} \
if (!desc->gdev->chip) { \
@@ -2040,7 +2056,14 @@ int gpiod_to_irq(const struct gpio_desc *desc)
struct gpio_chip *chip;
int offset;
- VALIDATE_DESC(desc);
+ /*
+ * Cannot VALIDATE_DESC() here as gpiod_to_irq() consumer semantics
+ * requires this function to not return zero on an invalid descriptor
+ * but rather a negative error number.
+ */
+ if (!desc || IS_ERR(desc) || !desc->gdev || !desc->gdev->chip)
+ return -EINVAL;
+
chip = desc->gdev->chip;
offset = gpio_chip_hwgpio(desc);
if (chip->to_irq) {
@@ -2066,17 +2089,30 @@ EXPORT_SYMBOL_GPL(gpiod_to_irq);
*/
int gpiochip_lock_as_irq(struct gpio_chip *chip, unsigned int offset)
{
- if (offset >= chip->ngpio)
- return -EINVAL;
+ struct gpio_desc *desc;
- if (test_bit(FLAG_IS_OUT, &chip->gpiodev->descs[offset].flags)) {
+ desc = gpiochip_get_desc(chip, offset);
+ if (IS_ERR(desc))
+ return PTR_ERR(desc);
+
+ /* Flush direction if something changed behind our back */
+ if (chip->get_direction) {
+ int dir = chip->get_direction(chip, offset);
+
+ if (dir)
+ clear_bit(FLAG_IS_OUT, &desc->flags);
+ else
+ set_bit(FLAG_IS_OUT, &desc->flags);
+ }
+
+ if (test_bit(FLAG_IS_OUT, &desc->flags)) {
chip_err(chip,
"%s: tried to flag a GPIO set as output for IRQ\n",
__func__);
return -EIO;
}
- set_bit(FLAG_USED_AS_IRQ, &chip->gpiodev->descs[offset].flags);
+ set_bit(FLAG_USED_AS_IRQ, &desc->flags);
return 0;
}
EXPORT_SYMBOL_GPL(gpiochip_lock_as_irq);
@@ -2543,28 +2579,13 @@ struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
}
EXPORT_SYMBOL_GPL(gpiod_get_optional);
-/**
- * gpiod_parse_flags - helper function to parse GPIO lookup flags
- * @desc: gpio to be setup
- * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
- * of_get_gpio_hog()
- *
- * Set the GPIO descriptor flags based on the given GPIO lookup flags.
- */
-static void gpiod_parse_flags(struct gpio_desc *desc, unsigned long lflags)
-{
- if (lflags & GPIO_ACTIVE_LOW)
- set_bit(FLAG_ACTIVE_LOW, &desc->flags);
- if (lflags & GPIO_OPEN_DRAIN)
- set_bit(FLAG_OPEN_DRAIN, &desc->flags);
- if (lflags & GPIO_OPEN_SOURCE)
- set_bit(FLAG_OPEN_SOURCE, &desc->flags);
-}
/**
* gpiod_configure_flags - helper function to configure a given GPIO
* @desc: gpio whose value will be assigned
* @con_id: function within the GPIO consumer
+ * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
+ * of_get_gpio_hog()
* @dflags: gpiod_flags - optional GPIO initialization flags
*
* Return 0 on success, -ENOENT if no GPIO has been assigned to the
@@ -2572,10 +2593,17 @@ static void gpiod_parse_flags(struct gpio_desc *desc, unsigned long lflags)
* occurred while trying to acquire the GPIO.
*/
static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
- enum gpiod_flags dflags)
+ unsigned long lflags, enum gpiod_flags dflags)
{
int status;
+ if (lflags & GPIO_ACTIVE_LOW)
+ set_bit(FLAG_ACTIVE_LOW, &desc->flags);
+ if (lflags & GPIO_OPEN_DRAIN)
+ set_bit(FLAG_OPEN_DRAIN, &desc->flags);
+ if (lflags & GPIO_OPEN_SOURCE)
+ set_bit(FLAG_OPEN_SOURCE, &desc->flags);
+
/* No particular flag request, return here... */
if (!(dflags & GPIOD_FLAGS_BIT_DIR_SET)) {
pr_debug("no flags found for %s\n", con_id);
@@ -2642,13 +2670,11 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
return desc;
}
- gpiod_parse_flags(desc, lookupflags);
-
status = gpiod_request(desc, con_id);
if (status < 0)
return ERR_PTR(status);
- status = gpiod_configure_flags(desc, con_id, flags);
+ status = gpiod_configure_flags(desc, con_id, lookupflags, flags);
if (status < 0) {
dev_dbg(dev, "setup of GPIO %s failed\n", con_id);
gpiod_put(desc);
@@ -2704,6 +2730,10 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
if (IS_ERR(desc))
return desc;
+ ret = gpiod_request(desc, NULL);
+ if (ret)
+ return ERR_PTR(ret);
+
if (active_low)
set_bit(FLAG_ACTIVE_LOW, &desc->flags);
@@ -2714,10 +2744,6 @@ struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode,
set_bit(FLAG_OPEN_SOURCE, &desc->flags);
}
- ret = gpiod_request(desc, NULL);
- if (ret)
- return ERR_PTR(ret);
-
return desc;
}
EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
@@ -2770,8 +2796,6 @@ int gpiod_hog(struct gpio_desc *desc, const char *name,
chip = gpiod_to_chip(desc);
hwnum = gpio_chip_hwgpio(desc);
- gpiod_parse_flags(desc, lflags);
-
local_desc = gpiochip_request_own_desc(chip, hwnum, name);
if (IS_ERR(local_desc)) {
status = PTR_ERR(local_desc);
@@ -2780,7 +2804,7 @@ int gpiod_hog(struct gpio_desc *desc, const char *name,
return status;
}
- status = gpiod_configure_flags(desc, name, dflags);
+ status = gpiod_configure_flags(desc, name, lflags, dflags);
if (status < 0) {
pr_err("setup of hog GPIO %s (chip %s, offset %d) failed, %d\n",
name, chip->label, hwnum, status);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 15:13:09 +0000