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authorDave Airlie <airlied@redhat.com>2015-04-20 11:32:26 +1000
committerDave Airlie <airlied@redhat.com>2015-04-20 13:05:20 +1000
commit2c33ce009ca2389dbf0535d0672214d09738e35e (patch)
tree6186a6458c3c160385d794a23eaf07c786a9e61b /drivers/gpio/gpiolib.c
parentcec32a47010647e8b0603726ebb75b990a4057a4 (diff)
parent09d51602cf84a1264946711dd4ea0dddbac599a1 (diff)
downloadlinux-stable-2c33ce009ca2389dbf0535d0672214d09738e35e.tar.gz
linux-stable-2c33ce009ca2389dbf0535d0672214d09738e35e.tar.bz2
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Merge Linus master into drm-next
The merge is clean, but the arm build fails afterwards, due to API changes in the regulator tree. I've included the patch into the merge to fix the build. Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c299
1 files changed, 265 insertions, 34 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 1ca9295b2c10..59eaa23767d8 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -315,6 +315,7 @@ EXPORT_SYMBOL_GPL(gpiochip_add);
/* 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
@@ -333,6 +334,7 @@ void gpiochip_remove(struct gpio_chip *chip)
acpi_gpiochip_remove(chip);
gpiochip_remove_pin_ranges(chip);
+ gpiochip_free_hogs(chip);
of_gpiochip_remove(chip);
spin_lock_irqsave(&gpio_lock, flags);
@@ -866,6 +868,7 @@ static bool __gpiod_free(struct gpio_desc *desc)
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;
}
@@ -1659,19 +1662,18 @@ static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
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);
@@ -1692,7 +1694,6 @@ static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
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;
@@ -1700,13 +1701,13 @@ static struct gpio_desc *acpi_find_gpio(struct device *dev, const char *con_id,
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);
@@ -1805,6 +1806,70 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
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
@@ -1840,6 +1905,47 @@ struct gpio_desc *__must_check __gpiod_get_optional(struct device *dev,
}
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
@@ -1865,13 +1971,15 @@ struct gpio_desc *__must_check __gpiod_get_index(struct device *dev,
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);
+ }
}
/*
@@ -1889,28 +1997,10 @@ struct gpio_desc *__must_check __gpiod_get_index(struct device *dev,
}
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);
@@ -2006,6 +2096,132 @@ struct gpio_desc *__must_check __gpiod_get_index_optional(struct device *dev,
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
*
@@ -2017,6 +2233,21 @@ void gpiod_put(struct gpio_desc *desc)
}
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)