/* Forward-declaration */
static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip);
+static void gpiochip_free_hogs(struct gpio_chip *chip);
/**
* gpiochip_remove() - unregister a gpio_chip
acpi_gpiochip_remove(chip);
gpiochip_remove_pin_ranges(chip);
+ gpiochip_free_hogs(chip);
of_gpiochip_remove(chip);
spin_lock_irqsave(&gpio_lock, flags);
clear_bit(FLAG_REQUESTED, &desc->flags);
clear_bit(FLAG_OPEN_DRAIN, &desc->flags);
clear_bit(FLAG_OPEN_SOURCE, &desc->flags);
+ clear_bit(FLAG_IS_HOGGED, &desc->flags);
ret = true;
}
unsigned int idx,
enum gpio_lookup_flags *flags)
{
- static const char * const suffixes[] = { "gpios", "gpio" };
char prop_name[32]; /* 32 is max size of property name */
enum of_gpio_flags of_flags;
struct gpio_desc *desc;
unsigned int i;
- for (i = 0; i < ARRAY_SIZE(suffixes); i++) {
+ for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
if (con_id)
snprintf(prop_name, sizeof(prop_name), "%s-%s", con_id,
- suffixes[i]);
+ gpio_suffixes[i]);
else
snprintf(prop_name, sizeof(prop_name), "%s",
- suffixes[i]);
+ gpio_suffixes[i]);
desc = of_get_named_gpiod_flags(dev->of_node, prop_name, idx,
&of_flags);
unsigned int idx,
enum gpio_lookup_flags *flags)
{
- static const char * const suffixes[] = { "gpios", "gpio" };
struct acpi_device *adev = ACPI_COMPANION(dev);
struct acpi_gpio_info info;
struct gpio_desc *desc;
int i;
/* Try first from _DSD */
- for (i = 0; i < ARRAY_SIZE(suffixes); i++) {
+ for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
if (con_id && strcmp(con_id, "gpios")) {
snprintf(propname, sizeof(propname), "%s-%s",
- con_id, suffixes[i]);
+ con_id, gpio_suffixes[i]);
} else {
snprintf(propname, sizeof(propname), "%s",
- suffixes[i]);
+ gpio_suffixes[i]);
}
desc = acpi_get_gpiod_by_index(adev, propname, idx, &info);
return desc;
}
+static int dt_gpio_count(struct device *dev, const char *con_id)
+{
+ int ret;
+ char propname[32];
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) {
+ if (con_id)
+ snprintf(propname, sizeof(propname), "%s-%s",
+ con_id, gpio_suffixes[i]);
+ else
+ snprintf(propname, sizeof(propname), "%s",
+ gpio_suffixes[i]);
+
+ ret = of_gpio_named_count(dev->of_node, propname);
+ if (ret >= 0)
+ break;
+ }
+ return ret;
+}
+
+static int platform_gpio_count(struct device *dev, const char *con_id)
+{
+ struct gpiod_lookup_table *table;
+ struct gpiod_lookup *p;
+ unsigned int count = 0;
+
+ table = gpiod_find_lookup_table(dev);
+ if (!table)
+ return -ENOENT;
+
+ for (p = &table->table[0]; p->chip_label; p++) {
+ if ((con_id && p->con_id && !strcmp(con_id, p->con_id)) ||
+ (!con_id && !p->con_id))
+ count++;
+ }
+ if (!count)
+ return -ENOENT;
+
+ return count;
+}
+
+/**
+ * gpiod_count - return the number of GPIOs associated with a device / function
+ * or -ENOENT if no GPIO has been assigned to the requested function
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
+ * @con_id: function within the GPIO consumer
+ */
+int gpiod_count(struct device *dev, const char *con_id)
+{
+ int count = -ENOENT;
+
+ if (IS_ENABLED(CONFIG_OF) && dev && dev->of_node)
+ count = dt_gpio_count(dev, con_id);
+ else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev))
+ count = acpi_gpio_count(dev, con_id);
+
+ if (count < 0)
+ count = platform_gpio_count(dev, con_id);
+
+ return count;
+}
+EXPORT_SYMBOL_GPL(gpiod_count);
+
/**
* gpiod_get - obtain a GPIO for a given GPIO function
* @dev: GPIO consumer, can be NULL for system-global GPIOs
}
EXPORT_SYMBOL_GPL(__gpiod_get_optional);
+
+/**
+ * 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
+ * requested function and/or index, or another IS_ERR() code if an error
+ * occurred while trying to acquire the GPIO.
+ */
+static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
+ 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);
+ return 0;
+ }
+
+ /* Process flags */
+ if (dflags & GPIOD_FLAGS_BIT_DIR_OUT)
+ status = gpiod_direction_output(desc,
+ dflags & GPIOD_FLAGS_BIT_DIR_VAL);
+ else
+ status = gpiod_direction_input(desc);
+
+ return status;
+}
+
/**
* gpiod_get_index - obtain a GPIO from a multi-index GPIO function
* @dev: GPIO consumer, can be NULL for system-global GPIOs
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, &lookupflags);
- } else if (IS_ENABLED(CONFIG_ACPI) && dev && ACPI_HANDLE(dev)) {
- dev_dbg(dev, "using ACPI for GPIO lookup\n");
- desc = acpi_find_gpio(dev, con_id, idx, &lookupflags);
+ if (dev) {
+ /* Using device tree? */
+ if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
+ dev_dbg(dev, "using device tree for GPIO lookup\n");
+ desc = of_find_gpio(dev, con_id, idx, &lookupflags);
+ } else if (ACPI_COMPANION(dev)) {
+ dev_dbg(dev, "using ACPI for GPIO lookup\n");
+ desc = acpi_find_gpio(dev, con_id, idx, &lookupflags);
+ }
}
/*
}
status = gpiod_request(desc, con_id);
-
if (status < 0)
return ERR_PTR(status);
- if (lookupflags & GPIO_ACTIVE_LOW)
- set_bit(FLAG_ACTIVE_LOW, &desc->flags);
- if (lookupflags & GPIO_OPEN_DRAIN)
- set_bit(FLAG_OPEN_DRAIN, &desc->flags);
- if (lookupflags & GPIO_OPEN_SOURCE)
- set_bit(FLAG_OPEN_SOURCE, &desc->flags);
-
- /* No particular flag request, return here... */
- if (!(flags & GPIOD_FLAGS_BIT_DIR_SET))
- return desc;
-
- /* Process flags */
- if (flags & GPIOD_FLAGS_BIT_DIR_OUT)
- status = gpiod_direction_output(desc,
- flags & GPIOD_FLAGS_BIT_DIR_VAL);
- else
- status = gpiod_direction_input(desc);
-
+ 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);
}
EXPORT_SYMBOL_GPL(__gpiod_get_index_optional);
+/**
+ * gpiod_hog - Hog the specified GPIO desc given the provided flags
+ * @desc: gpio whose value will be assigned
+ * @name: gpio line name
+ * @lflags: gpio_lookup_flags - returned from of_find_gpio() or
+ * of_get_gpio_hog()
+ * @dflags: gpiod_flags - optional GPIO initialization flags
+ */
+int gpiod_hog(struct gpio_desc *desc, const char *name,
+ unsigned long lflags, enum gpiod_flags dflags)
+{
+ struct gpio_chip *chip;
+ struct gpio_desc *local_desc;
+ int hwnum;
+ int status;
+
+ chip = gpiod_to_chip(desc);
+ hwnum = gpio_chip_hwgpio(desc);
+
+ local_desc = gpiochip_request_own_desc(chip, hwnum, name);
+ if (IS_ERR(local_desc)) {
+ pr_debug("requesting own GPIO %s failed\n", name);
+ return PTR_ERR(local_desc);
+ }
+
+ status = gpiod_configure_flags(desc, name, lflags, dflags);
+ if (status < 0) {
+ pr_debug("setup of GPIO %s failed\n", name);
+ gpiochip_free_own_desc(desc);
+ return status;
+ }
+
+ /* Mark GPIO as hogged so it can be identified and removed later */
+ set_bit(FLAG_IS_HOGGED, &desc->flags);
+
+ pr_info("GPIO line %d (%s) hogged as %s%s\n",
+ desc_to_gpio(desc), name,
+ (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ? "output" : "input",
+ (dflags&GPIOD_FLAGS_BIT_DIR_OUT) ?
+ (dflags&GPIOD_FLAGS_BIT_DIR_VAL) ? "/high" : "/low":"");
+
+ return 0;
+}
+
+/**
+ * gpiochip_free_hogs - Scan gpio-controller chip and release GPIO hog
+ * @chip: gpio chip to act on
+ *
+ * This is only used by of_gpiochip_remove to free hogged gpios
+ */
+static void gpiochip_free_hogs(struct gpio_chip *chip)
+{
+ int id;
+
+ for (id = 0; id < chip->ngpio; id++) {
+ if (test_bit(FLAG_IS_HOGGED, &chip->desc[id].flags))
+ gpiochip_free_own_desc(&chip->desc[id]);
+ }
+}
+
+/**
+ * gpiod_get_array - obtain multiple GPIOs from a multi-index GPIO function
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
+ * @con_id: function within the GPIO consumer
+ * @flags: optional GPIO initialization flags
+ *
+ * This function acquires all the GPIOs defined under a given function.
+ *
+ * Return a struct gpio_descs containing an array of descriptors, -ENOENT if
+ * no GPIO has been assigned to the requested function, or another IS_ERR()
+ * code if an error occurred while trying to acquire the GPIOs.
+ */
+struct gpio_descs *__must_check gpiod_get_array(struct device *dev,
+ const char *con_id,
+ enum gpiod_flags flags)
+{
+ struct gpio_desc *desc;
+ struct gpio_descs *descs;
+ int count;
+
+ count = gpiod_count(dev, con_id);
+ if (count < 0)
+ return ERR_PTR(count);
+
+ descs = kzalloc(sizeof(*descs) + sizeof(descs->desc[0]) * count,
+ GFP_KERNEL);
+ if (!descs)
+ return ERR_PTR(-ENOMEM);
+
+ for (descs->ndescs = 0; descs->ndescs < count; ) {
+ desc = gpiod_get_index(dev, con_id, descs->ndescs, flags);
+ if (IS_ERR(desc)) {
+ gpiod_put_array(descs);
+ return ERR_CAST(desc);
+ }
+ descs->desc[descs->ndescs] = desc;
+ descs->ndescs++;
+ }
+ return descs;
+}
+EXPORT_SYMBOL_GPL(gpiod_get_array);
+
+/**
+ * gpiod_get_array_optional - obtain multiple GPIOs from a multi-index GPIO
+ * function
+ * @dev: GPIO consumer, can be NULL for system-global GPIOs
+ * @con_id: function within the GPIO consumer
+ * @flags: optional GPIO initialization flags
+ *
+ * This is equivalent to gpiod_get_array(), except that when no GPIO was
+ * assigned to the requested function it will return NULL.
+ */
+struct gpio_descs *__must_check gpiod_get_array_optional(struct device *dev,
+ const char *con_id,
+ enum gpiod_flags flags)
+{
+ struct gpio_descs *descs;
+
+ descs = gpiod_get_array(dev, con_id, flags);
+ if (IS_ERR(descs) && (PTR_ERR(descs) == -ENOENT))
+ return NULL;
+
+ return descs;
+}
+EXPORT_SYMBOL_GPL(gpiod_get_array_optional);
+
/**
* gpiod_put - dispose of a GPIO descriptor
* @desc: GPIO descriptor to dispose of
}
EXPORT_SYMBOL_GPL(gpiod_put);
+/**
+ * gpiod_put_array - dispose of multiple GPIO descriptors
+ * @descs: struct gpio_descs containing an array of descriptors
+ */
+void gpiod_put_array(struct gpio_descs *descs)
+{
+ unsigned int i;
+
+ for (i = 0; i < descs->ndescs; i++)
+ gpiod_put(descs->desc[i]);
+
+ kfree(descs);
+}
+EXPORT_SYMBOL_GPL(gpiod_put_array);
+
#ifdef CONFIG_DEBUG_FS
static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
projects / firefly-linux-kernel-4.4.55.git / blobdiff