#include <linux/device.h>
#include <linux/gfp.h>
+static void devm_gpiod_release(struct device *dev, void *res)
+{
+ struct gpio_desc **desc = res;
+
+ gpiod_put(*desc);
+}
+
+static int devm_gpiod_match(struct device *dev, void *res, void *data)
+{
+ struct gpio_desc **this = res, **gpio = data;
+
+ return *this == *gpio;
+}
+
+/**
+ * devm_gpiod_get - Resource-managed gpiod_get()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ *
+ * Managed gpiod_get(). GPIO descriptors returned from this function are
+ * automatically disposed on driver detach. See gpiod_get() for detailed
+ * information about behavior and return values.
+ */
+struct gpio_desc *__must_check devm_gpiod_get(struct device *dev,
+ const char *con_id)
+{
+ return devm_gpiod_get_index(dev, con_id, 0);
+}
+EXPORT_SYMBOL(devm_gpiod_get);
+
+/**
+ * devm_gpiod_get_index - Resource-managed gpiod_get_index()
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @idx: index of the GPIO to obtain in the consumer
+ *
+ * Managed gpiod_get_index(). GPIO descriptors returned from this function are
+ * automatically disposed on driver detach. See gpiod_get_index() for detailed
+ * information about behavior and return values.
+ */
+struct gpio_desc *__must_check devm_gpiod_get_index(struct device *dev,
+ const char *con_id,
+ unsigned int idx)
+{
+ struct gpio_desc **dr;
+ struct gpio_desc *desc;
+
+ dr = devres_alloc(devm_gpiod_release, sizeof(struct gpiod_desc *),
+ GFP_KERNEL);
+ if (!dr)
+ return ERR_PTR(-ENOMEM);
+
+ desc = gpiod_get_index(dev, con_id, idx);
+ if (IS_ERR(desc)) {
+ devres_free(dr);
+ return desc;
+ }
+
+ *dr = desc;
+ devres_add(dev, dr);
+
+ return 0;
+}
+EXPORT_SYMBOL(devm_gpiod_get_index);
+
+/**
+ * devm_gpiod_put - Resource-managed gpiod_put()
+ * @desc: GPIO descriptor to dispose of
+ *
+ * Dispose of a GPIO descriptor obtained with devm_gpiod_get() or
+ * devm_gpiod_get_index(). Normally this function will not be called as the GPIO
+ * will be disposed of by the resource management code.
+ */
+void devm_gpiod_put(struct device *dev, struct gpio_desc *desc)
+{
+ WARN_ON(devres_release(dev, devm_gpiod_release, devm_gpiod_match,
+ &desc));
+}
+EXPORT_SYMBOL(devm_gpiod_put);
+
+
+
+
static void devm_gpio_release(struct device *dev, void *res)
{
unsigned *gpio = res;
#define GPIO_OFFSET_VALID(chip, offset) (offset >= 0 && offset < chip->ngpio)
+static DEFINE_MUTEX(gpio_lookup_lock);
+static LIST_HEAD(gpio_lookup_list);
static LIST_HEAD(gpio_chips);
#ifdef CONFIG_GPIO_SYSFS
}
EXPORT_SYMBOL_GPL(gpiod_set_value_cansleep);
+/**
+ * gpiod_add_table() - register GPIO device consumers
+ * @table: array of consumers to register
+ * @num: number of consumers in table
+ */
+void gpiod_add_table(struct gpiod_lookup *table, size_t size)
+{
+ mutex_lock(&gpio_lookup_lock);
+
+ while (size--) {
+ list_add_tail(&table->list, &gpio_lookup_list);
+ table++;
+ }
+
+ mutex_unlock(&gpio_lookup_lock);
+}
+
+/*
+ * Caller must have a acquired gpio_lookup_lock
+ */
+static struct gpio_chip *find_chip_by_name(const char *name)
+{
+ struct gpio_chip *chip = NULL;
+
+ list_for_each_entry(chip, &gpio_lookup_list, list) {
+ if (chip->label == NULL)
+ continue;
+ if (!strcmp(chip->label, name))
+ break;
+ }
+
+ return chip;
+}
+
+#ifdef CONFIG_OF
+static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
+ unsigned int idx, unsigned long *flags)
+{
+ char prop_name[32]; /* 32 is max size of property name */
+ enum of_gpio_flags of_flags;
+ struct gpio_desc *desc;
+
+ if (con_id)
+ snprintf(prop_name, 32, "%s-gpios", con_id);
+ else
+ snprintf(prop_name, 32, "gpios");
+
+ desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
+ &of_flags);
+
+ if (IS_ERR(desc))
+ return desc;
+
+ if (of_flags & OF_GPIO_ACTIVE_LOW)
+ *flags |= GPIOF_ACTIVE_LOW;
+
+ return desc;
+}
+#else
+static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
+ unsigned int idx, unsigned long *flags)
+{
+ return ERR_PTR(-ENODEV);
+}
+#endif
+
+static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
+ unsigned int idx, unsigned long *flags)
+{
+ const char *dev_id = dev ? dev_name(dev) : NULL;
+ struct gpio_desc *desc = ERR_PTR(-ENODEV);
+ unsigned int match, best = 0;
+ struct gpiod_lookup *p;
+
+ mutex_lock(&gpio_lookup_lock);
+
+ list_for_each_entry(p, &gpio_lookup_list, list) {
+ match = 0;
+
+ if (p->dev_id) {
+ if (!dev_id || strcmp(p->dev_id, dev_id))
+ continue;
+
+ match += 2;
+ }
+
+ if (p->con_id) {
+ if (!con_id || strcmp(p->con_id, con_id))
+ continue;
+
+ match += 1;
+ }
+
+ if (p->idx != idx)
+ continue;
+
+ if (match > best) {
+ struct gpio_chip *chip;
+
+ chip = find_chip_by_name(p->chip_label);
+
+ if (!chip) {
+ dev_warn(dev, "cannot find GPIO chip %s\n",
+ p->chip_label);
+ continue;
+ }
+
+ if (chip->ngpio >= p->chip_hwnum) {
+ dev_warn(dev, "GPIO chip %s has %d GPIOs\n",
+ chip->label, chip->ngpio);
+ continue;
+ }
+
+ desc = gpio_to_desc(chip->base + p->chip_hwnum);
+ *flags = p->flags;
+
+ if (match != 3)
+ best = match;
+ else
+ break;
+ }
+ }
+
+ mutex_unlock(&gpio_lookup_lock);
+
+ return desc;
+}
+
+/**
+ * gpio_get - obtain a GPIO for a given GPIO function
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ *
+ * Return the GPIO descriptor corresponding to the function con_id of device
+ * dev, or an IS_ERR() condition if an error occured.
+ */
+struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id)
+{
+ return gpiod_get_index(dev, con_id, 0);
+}
+EXPORT_SYMBOL_GPL(gpiod_get);
+
+/**
+ * gpiod_get_index - obtain a GPIO from a multi-index GPIO function
+ * @dev: GPIO consumer
+ * @con_id: function within the GPIO consumer
+ * @idx: index of the GPIO to obtain in the consumer
+ *
+ * This variant of gpiod_get() allows to access GPIOs other than the first
+ * defined one for functions that define several GPIOs.
+ *
+ * Return a valid GPIO descriptor, or an IS_ERR() condition in case of error.
+ */
+struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
+ const char *con_id,
+ unsigned int idx)
+{
+ struct gpio_desc *desc;
+ int status;
+ unsigned long flags = 0;
+
+ dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id);
+
+ /* Using device tree? */
+ if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node) {
+ dev_dbg(dev, "using device tree for GPIO lookup\n");
+ desc = of_find_gpio(dev, con_id, idx, &flags);
+ } else {
+ dev_dbg(dev, "using lookup tables for GPIO lookup");
+ desc = gpiod_find(dev, con_id, idx, &flags);
+ }
+
+ if (IS_ERR(desc)) {
+ dev_warn(dev, "lookup for GPIO %s failed\n", con_id);
+ return desc;
+ }
+
+ status = gpiod_request(desc, con_id);
+
+ if (status < 0)
+ return ERR_PTR(status);
+
+ if (flags & GPIOF_ACTIVE_LOW)
+ set_bit(FLAG_ACTIVE_LOW, &desc->flags);
+
+ return desc;
+}
+EXPORT_SYMBOL_GPL(gpiod_get_index);
+
+/**
+ * gpiod_put - dispose of a GPIO descriptor
+ * @desc: GPIO descriptor to dispose of
+ *
+ * No descriptor can be used after gpiod_put() has been called on it.
+ */
+void gpiod_put(struct gpio_desc *desc)
+{
+ gpiod_free(desc);
+}
+EXPORT_SYMBOL_GPL(gpiod_put);
+
#ifdef CONFIG_DEBUG_FS
static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
int gpiod_lock_as_irq(struct gpio_desc *desc);
void gpiod_unlock_as_irq(struct gpio_desc *desc);
+/**
+ * Lookup table for associating GPIOs to specific devices and functions using
+ * platform data.
+ */
+struct gpiod_lookup {
+ struct list_head list;
+ /*
+ * name of the chip the GPIO belongs to
+ */
+ const char *chip_label;
+ /*
+ * hardware number (i.e. relative to the chip) of the GPIO
+ */
+ u16 chip_hwnum;
+ /*
+ * name of device that can claim this GPIO
+ */
+ const char *dev_id;
+ /*
+ * name of the GPIO from the device's point of view
+ */
+ const char *con_id;
+ /*
+ * index of the GPIO in case several GPIOs share the same name
+ */
+ unsigned int idx;
+ /*
+ * mask of GPIOF_* values
+ */
+ unsigned long flags;
+};
+
+/*
+ * Simple definition of a single GPIO under a con_id
+ */
+#define GPIO_LOOKUP(_chip_label, _chip_hwnum, _dev_id, _con_id, _flags) \
+ GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _dev_id, _con_id, 0, _flags)
+
+/*
+ * Use this macro if you need to have several GPIOs under the same con_id.
+ * Each GPIO needs to use a different index and can be accessed using
+ * gpiod_get_index()
+ */
+#define GPIO_LOOKUP_IDX(_chip_label, _chip_hwnum, _dev_id, _con_id, _idx, \
+ _flags) \
+{ \
+ .chip_label = _chip_label, \
+ .chip_hwnum = _chip_hwnum, \
+ .dev_id = _dev_id, \
+ .con_id = _con_id, \
+ .idx = _idx, \
+ .flags = _flags, \
+}
+
+void gpiod_add_table(struct gpiod_lookup *table, size_t size);
+
#endif
projects / kernel / kernel-generic.git / commitdiff