diff options
author | Johan Hovold <johan@kernel.org> | 2015-05-04 18:10:37 +0300 |
---|---|---|
committer | Linus Walleij <linus.walleij@linaro.org> | 2015-05-12 11:47:12 +0300 |
commit | c43960fbcc514b0ec8169a66ba9955608e6775a7 (patch) | |
tree | 10c73074ebb45203f2d7446ed7c24f06a19ce8e1 /drivers/gpio | |
parent | f0b7866a02370d9a03b0be497b9f88d982b8b67d (diff) | |
download | linux-c43960fbcc514b0ec8169a66ba9955608e6775a7.tar.xz |
gpio: sysfs: add gpiod class-device data
Add gpiod class-device data.
This is a first step in getting rid of the insane gpio-descriptor flag
overloading, backward irq-interface implementation, and course grained
sysfs-interface locking (a single static mutex for every operation on
all exported gpios in a system).
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/gpio')
-rw-r--r-- | drivers/gpio/gpiolib-sysfs.c | 62 |
1 files changed, 46 insertions, 16 deletions
diff --git a/drivers/gpio/gpiolib-sysfs.c b/drivers/gpio/gpiolib-sysfs.c index 10baf31efe74..097e7e539c9d 100644 --- a/drivers/gpio/gpiolib-sysfs.c +++ b/drivers/gpio/gpiolib-sysfs.c @@ -6,9 +6,14 @@ #include <linux/gpio/driver.h> #include <linux/interrupt.h> #include <linux/kdev_t.h> +#include <linux/slab.h> #include "gpiolib.h" +struct gpiod_data { + struct gpio_desc *desc; +}; + static DEFINE_IDR(dirent_idr); @@ -41,7 +46,8 @@ static DEFINE_MUTEX(sysfs_lock); static ssize_t direction_show(struct device *dev, struct device_attribute *attr, char *buf) { - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; mutex_lock(&sysfs_lock); @@ -58,7 +64,8 @@ static ssize_t direction_show(struct device *dev, static ssize_t direction_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; mutex_lock(&sysfs_lock); @@ -80,7 +87,8 @@ static DEVICE_ATTR_RW(direction); static ssize_t value_show(struct device *dev, struct device_attribute *attr, char *buf) { - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; mutex_lock(&sysfs_lock); @@ -94,7 +102,8 @@ static ssize_t value_show(struct device *dev, static ssize_t value_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; mutex_lock(&sysfs_lock); @@ -225,7 +234,8 @@ static const struct { static ssize_t edge_show(struct device *dev, struct device_attribute *attr, char *buf) { - const struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; unsigned long mask; ssize_t status = 0; int i; @@ -247,7 +257,8 @@ static ssize_t edge_show(struct device *dev, static ssize_t edge_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; int i; @@ -297,7 +308,8 @@ static int sysfs_set_active_low(struct gpio_desc *desc, struct device *dev, static ssize_t active_low_show(struct device *dev, struct device_attribute *attr, char *buf) { - const struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; mutex_lock(&sysfs_lock); @@ -313,7 +325,8 @@ static ssize_t active_low_show(struct device *dev, static ssize_t active_low_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t size) { - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; ssize_t status; long value; @@ -333,7 +346,8 @@ static umode_t gpio_is_visible(struct kobject *kobj, struct attribute *attr, int n) { struct device *dev = container_of(kobj, struct device, kobj); - struct gpio_desc *desc = dev_get_drvdata(dev); + struct gpiod_data *data = dev_get_drvdata(dev); + struct gpio_desc *desc = data->desc; umode_t mode = attr->mode; bool show_direction = test_bit(FLAG_SYSFS_DIR, &desc->flags); @@ -525,6 +539,7 @@ static struct class gpio_class = { int gpiod_export(struct gpio_desc *desc, bool direction_may_change) { struct gpio_chip *chip; + struct gpiod_data *data; unsigned long flags; int status; const char *ioname = NULL; @@ -549,7 +564,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) /* check if chip is being removed */ if (!chip || !chip->cdev) { status = -ENODEV; - goto fail_unlock; + goto err_unlock; } spin_lock_irqsave(&gpio_lock, flags); @@ -561,7 +576,7 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) test_bit(FLAG_REQUESTED, &desc->flags), test_bit(FLAG_EXPORT, &desc->flags)); status = -EPERM; - goto fail_unlock; + goto err_unlock; } if (chip->direction_input && chip->direction_output && @@ -571,33 +586,45 @@ int gpiod_export(struct gpio_desc *desc, bool direction_may_change) spin_unlock_irqrestore(&gpio_lock, flags); + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) { + status = -ENOMEM; + goto err_unlock; + } + + data->desc = desc; + offset = gpio_chip_hwgpio(desc); if (chip->names && chip->names[offset]) ioname = chip->names[offset]; dev = device_create_with_groups(&gpio_class, chip->dev, - MKDEV(0, 0), desc, gpio_groups, + MKDEV(0, 0), data, gpio_groups, ioname ? ioname : "gpio%u", desc_to_gpio(desc)); if (IS_ERR(dev)) { status = PTR_ERR(dev); - goto fail_unlock; + goto err_free_data; } set_bit(FLAG_EXPORT, &desc->flags); mutex_unlock(&sysfs_lock); return 0; -fail_unlock: +err_free_data: + kfree(data); +err_unlock: mutex_unlock(&sysfs_lock); gpiod_dbg(desc, "%s: status %d\n", __func__, status); return status; } EXPORT_SYMBOL_GPL(gpiod_export); -static int match_export(struct device *dev, const void *data) +static int match_export(struct device *dev, const void *desc) { - return dev_get_drvdata(dev) == data; + struct gpiod_data *data = dev_get_drvdata(dev); + + return data->desc == desc; } /** @@ -653,6 +680,7 @@ EXPORT_SYMBOL_GPL(gpiod_export_link); */ void gpiod_unexport(struct gpio_desc *desc) { + struct gpiod_data *data; int status = 0; struct device *dev = NULL; @@ -676,6 +704,7 @@ void gpiod_unexport(struct gpio_desc *desc) mutex_unlock(&sysfs_lock); if (dev) { + data = dev_get_drvdata(dev); device_unregister(dev); /* * Release irq after deregistration to prevent race with @@ -683,6 +712,7 @@ void gpiod_unexport(struct gpio_desc *desc) */ gpio_setup_irq(desc, dev, 0); put_device(dev); + kfree(data); } if (status) |