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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.c118
1 files changed, 76 insertions, 42 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index bf4bd1d12..5db344555 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -190,7 +190,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_direction);
*/
static int gpiochip_add_to_list(struct gpio_chip *chip)
{
- struct list_head *pos = &gpio_chips;
+ struct list_head *pos;
struct gpio_chip *_chip;
int err = 0;
@@ -287,7 +287,13 @@ int gpiochip_add(struct gpio_chip *chip)
INIT_LIST_HEAD(&chip->pin_ranges);
#endif
- of_gpiochip_add(chip);
+ if (!chip->owner && chip->dev && chip->dev->driver)
+ chip->owner = chip->dev->driver->owner;
+
+ status = of_gpiochip_add(chip);
+ if (status)
+ goto err_remove_chip;
+
acpi_gpiochip_add(chip);
status = gpiochip_sysfs_register(chip);
@@ -443,8 +449,8 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
* The parent irqchip is already using the chip_data for this
* irqchip, so our callbacks simply use the handler_data.
*/
- irq_set_handler_data(parent_irq, gpiochip);
- irq_set_chained_handler(parent_irq, parent_handler);
+ irq_set_chained_handler_and_data(parent_irq, parent_handler,
+ gpiochip);
gpiochip->irq_parent = parent_irq;
}
@@ -456,12 +462,6 @@ void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip,
}
EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip);
-/*
- * This lock class tells lockdep that GPIO irqs are in a different
- * category than their parents, so it won't report false recursion.
- */
-static struct lock_class_key gpiochip_irq_lock_class;
-
/**
* gpiochip_irq_map() - maps an IRQ into a GPIO irqchip
* @d: the irqdomain used by this irqchip
@@ -478,16 +478,17 @@ static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq,
struct gpio_chip *chip = d->host_data;
irq_set_chip_data(irq, chip);
- irq_set_lockdep_class(irq, &gpiochip_irq_lock_class);
+ /*
+ * This lock class tells lockdep that GPIO irqs are in a different
+ * category than their parents, so it won't report false recursion.
+ */
+ irq_set_lockdep_class(irq, chip->lock_key);
irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler);
/* Chips that can sleep need nested thread handlers */
if (chip->can_sleep && !chip->irq_not_threaded)
irq_set_nested_thread(irq, 1);
-#ifdef CONFIG_ARM
- set_irq_flags(irq, IRQF_VALID);
-#else
irq_set_noprobe(irq);
-#endif
+
/*
* No set-up of the hardware will happen if IRQ_TYPE_NONE
* is passed as default type.
@@ -502,9 +503,6 @@ static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq)
{
struct gpio_chip *chip = d->host_data;
-#ifdef CONFIG_ARM
- set_irq_flags(irq, 0);
-#endif
if (chip->can_sleep)
irq_set_nested_thread(irq, 0);
irq_set_chip_and_handler(irq, NULL, NULL);
@@ -522,10 +520,14 @@ static int gpiochip_irq_reqres(struct irq_data *d)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
+ if (!try_module_get(chip->owner))
+ return -ENODEV;
+
if (gpiochip_lock_as_irq(chip, d->hwirq)) {
chip_err(chip,
"unable to lock HW IRQ %lu for IRQ\n",
d->hwirq);
+ module_put(chip->owner);
return -EINVAL;
}
return 0;
@@ -536,6 +538,7 @@ static void gpiochip_irq_relres(struct irq_data *d)
struct gpio_chip *chip = irq_data_get_irq_chip_data(d);
gpiochip_unlock_as_irq(chip, d->hwirq);
+ module_put(chip->owner);
}
static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset)
@@ -584,6 +587,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
* @handler: the irq handler to use (often a predefined irq core function)
* @type: the default type for IRQs on this irqchip, pass IRQ_TYPE_NONE
* to have the core avoid setting up any default type in the hardware.
+ * @lock_key: lockdep class
*
* This function closely associates a certain irqchip with a certain
* gpiochip, providing an irq domain to translate the local IRQs to
@@ -599,11 +603,12 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip)
* the pins on the gpiochip can generate a unique IRQ. Everything else
* need to be open coded.
*/
-int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
- struct irq_chip *irqchip,
- unsigned int first_irq,
- irq_flow_handler_t handler,
- unsigned int type)
+int _gpiochip_irqchip_add(struct gpio_chip *gpiochip,
+ struct irq_chip *irqchip,
+ unsigned int first_irq,
+ irq_flow_handler_t handler,
+ unsigned int type,
+ struct lock_class_key *lock_key)
{
struct device_node *of_node;
unsigned int offset;
@@ -629,6 +634,7 @@ int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
gpiochip->irq_handler = handler;
gpiochip->irq_default_type = type;
gpiochip->to_irq = gpiochip_to_irq;
+ gpiochip->lock_key = lock_key;
gpiochip->irqdomain = irq_domain_add_simple(of_node,
gpiochip->ngpio, first_irq,
&gpiochip_domain_ops, gpiochip);
@@ -636,8 +642,16 @@ int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
gpiochip->irqchip = NULL;
return -EINVAL;
}
- irqchip->irq_request_resources = gpiochip_irq_reqres;
- irqchip->irq_release_resources = gpiochip_irq_relres;
+
+ /*
+ * It is possible for a driver to override this, but only if the
+ * alternative functions are both implemented.
+ */
+ if (!irqchip->irq_request_resources &&
+ !irqchip->irq_release_resources) {
+ irqchip->irq_request_resources = gpiochip_irq_reqres;
+ irqchip->irq_release_resources = gpiochip_irq_relres;
+ }
/*
* Prepare the mapping since the irqchip shall be orthogonal to
@@ -658,7 +672,7 @@ int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
return 0;
}
-EXPORT_SYMBOL_GPL(gpiochip_irqchip_add);
+EXPORT_SYMBOL_GPL(_gpiochip_irqchip_add);
#else /* CONFIG_GPIOLIB_IRQCHIP */
@@ -671,7 +685,7 @@ static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {}
/**
* gpiochip_add_pingroup_range() - add a range for GPIO <-> pin mapping
* @chip: the gpiochip to add the range for
- * @pinctrl: the dev_name() of the pin controller to map to
+ * @pctldev: the pin controller to map to
* @gpio_offset: the start offset in the current gpio_chip number space
* @pin_group: name of the pin group inside the pin controller
*/
@@ -1160,15 +1174,16 @@ EXPORT_SYMBOL_GPL(gpiod_is_active_low);
* that the GPIO was actually requested.
*/
-static bool _gpiod_get_raw_value(const struct gpio_desc *desc)
+static int _gpiod_get_raw_value(const struct gpio_desc *desc)
{
struct gpio_chip *chip;
- bool value;
int offset;
+ int value;
chip = desc->chip;
offset = gpio_chip_hwgpio(desc);
- value = chip->get ? chip->get(chip, offset) : false;
+ value = chip->get ? chip->get(chip, offset) : -EIO;
+ value = value < 0 ? value : !!value;
trace_gpio_value(desc_to_gpio(desc), 1, value);
return value;
}
@@ -1178,7 +1193,7 @@ static bool _gpiod_get_raw_value(const struct gpio_desc *desc)
* @desc: gpio whose value will be returned
*
* Return the GPIO's raw value, i.e. the value of the physical line disregarding
- * its ACTIVE_LOW status.
+ * its ACTIVE_LOW status, or negative errno on failure.
*
* This function should be called from contexts where we cannot sleep, and will
* complain if the GPIO chip functions potentially sleep.
@@ -1198,7 +1213,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_value);
* @desc: gpio whose value will be returned
*
* Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
- * account.
+ * account, or negative errno on failure.
*
* This function should be called from contexts where we cannot sleep, and will
* complain if the GPIO chip functions potentially sleep.
@@ -1212,6 +1227,9 @@ int gpiod_get_value(const struct gpio_desc *desc)
WARN_ON(desc->chip->can_sleep);
value = _gpiod_get_raw_value(desc);
+ if (value < 0)
+ return value;
+
if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
value = !value;
@@ -1534,7 +1552,7 @@ EXPORT_SYMBOL_GPL(gpiochip_unlock_as_irq);
* @desc: gpio whose value will be returned
*
* Return the GPIO's raw value, i.e. the value of the physical line disregarding
- * its ACTIVE_LOW status.
+ * its ACTIVE_LOW status, or negative errno on failure.
*
* This function is to be called from contexts that can sleep.
*/
@@ -1552,7 +1570,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_raw_value_cansleep);
* @desc: gpio whose value will be returned
*
* Return the GPIO's logical value, i.e. taking the ACTIVE_LOW status into
- * account.
+ * account, or negative errno on failure.
*
* This function is to be called from contexts that can sleep.
*/
@@ -1565,6 +1583,9 @@ int gpiod_get_value_cansleep(const struct gpio_desc *desc)
return 0;
value = _gpiod_get_raw_value(desc);
+ if (value < 0)
+ return value;
+
if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
value = !value;
@@ -1672,6 +1693,19 @@ void gpiod_add_lookup_table(struct gpiod_lookup_table *table)
mutex_unlock(&gpio_lookup_lock);
}
+/**
+ * gpiod_remove_lookup_table() - unregister GPIO device consumers
+ * @table: table of consumers to unregister
+ */
+void gpiod_remove_lookup_table(struct gpiod_lookup_table *table)
+{
+ mutex_lock(&gpio_lookup_lock);
+
+ list_del(&table->list);
+
+ mutex_unlock(&gpio_lookup_lock);
+}
+
static struct gpio_desc *of_find_gpio(struct device *dev, const char *con_id,
unsigned int idx,
enum gpio_lookup_flags *flags)
@@ -1894,12 +1928,12 @@ EXPORT_SYMBOL_GPL(gpiod_count);
* dev, -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 GPIO.
*/
-struct gpio_desc *__must_check __gpiod_get(struct device *dev, const char *con_id,
+struct gpio_desc *__must_check gpiod_get(struct device *dev, const char *con_id,
enum gpiod_flags flags)
{
return gpiod_get_index(dev, con_id, 0, flags);
}
-EXPORT_SYMBOL_GPL(__gpiod_get);
+EXPORT_SYMBOL_GPL(gpiod_get);
/**
* gpiod_get_optional - obtain an optional GPIO for a given GPIO function
@@ -1911,13 +1945,13 @@ EXPORT_SYMBOL_GPL(__gpiod_get);
* the requested function it will return NULL. This is convenient for drivers
* that need to handle optional GPIOs.
*/
-struct gpio_desc *__must_check __gpiod_get_optional(struct device *dev,
+struct gpio_desc *__must_check gpiod_get_optional(struct device *dev,
const char *con_id,
enum gpiod_flags flags)
{
return gpiod_get_index_optional(dev, con_id, 0, flags);
}
-EXPORT_SYMBOL_GPL(__gpiod_get_optional);
+EXPORT_SYMBOL_GPL(gpiod_get_optional);
/**
@@ -1974,7 +2008,7 @@ static int gpiod_configure_flags(struct gpio_desc *desc, const char *con_id,
* requested function and/or index, or another IS_ERR() code if an error
* occurred while trying to acquire the GPIO.
*/
-struct gpio_desc *__must_check __gpiod_get_index(struct device *dev,
+struct gpio_desc *__must_check gpiod_get_index(struct device *dev,
const char *con_id,
unsigned int idx,
enum gpiod_flags flags)
@@ -2023,7 +2057,7 @@ struct gpio_desc *__must_check __gpiod_get_index(struct device *dev,
return desc;
}
-EXPORT_SYMBOL_GPL(__gpiod_get_index);
+EXPORT_SYMBOL_GPL(gpiod_get_index);
/**
* fwnode_get_named_gpiod - obtain a GPIO from firmware node
@@ -2092,7 +2126,7 @@ EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod);
* specified index was assigned to the requested function it will return NULL.
* This is convenient for drivers that need to handle optional GPIOs.
*/
-struct gpio_desc *__must_check __gpiod_get_index_optional(struct device *dev,
+struct gpio_desc *__must_check gpiod_get_index_optional(struct device *dev,
const char *con_id,
unsigned int index,
enum gpiod_flags flags)
@@ -2107,7 +2141,7 @@ struct gpio_desc *__must_check __gpiod_get_index_optional(struct device *dev,
return desc;
}
-EXPORT_SYMBOL_GPL(__gpiod_get_index_optional);
+EXPORT_SYMBOL_GPL(gpiod_get_index_optional);
/**
* gpiod_hog - Hog the specified GPIO desc given the provided flags