diff options
author | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2014-06-08 10:24:07 +0400 |
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committer | Dmitry Torokhov <dmitry.torokhov@gmail.com> | 2014-06-08 10:24:07 +0400 |
commit | a292241cccb7e20e8b997a9a44177e7c98141859 (patch) | |
tree | a0b0bb95e7dce3233a2d8b203f9e326cdec7a00e /drivers/gpio/gpiolib.c | |
parent | d49cb7aeebb974713f9f7ab2991352d3050b095b (diff) | |
parent | 68807a0c2015cb40df4869e16651f0ce5cc14d52 (diff) | |
download | linux-a292241cccb7e20e8b997a9a44177e7c98141859.tar.xz |
Merge branch 'next' into for-linus
Prepare input updates for 3.16.
Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r-- | drivers/gpio/gpiolib.c | 417 |
1 files changed, 352 insertions, 65 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 50c4922fe53a..f48817d97480 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -164,16 +164,17 @@ struct gpio_desc *gpio_to_desc(unsigned gpio) EXPORT_SYMBOL_GPL(gpio_to_desc); /** - * Convert an offset on a certain chip to a corresponding descriptor + * Get the GPIO descriptor corresponding to the given hw number for this chip. */ -static struct gpio_desc *gpiochip_offset_to_desc(struct gpio_chip *chip, - unsigned int offset) +struct gpio_desc *gpiochip_get_desc(struct gpio_chip *chip, + u16 hwnum) { - if (offset >= chip->ngpio) + if (hwnum >= chip->ngpio) return ERR_PTR(-EINVAL); - return &chip->desc[offset]; + return &chip->desc[hwnum]; } +EXPORT_SYMBOL_GPL(gpiochip_get_desc); /** * Convert a GPIO descriptor to the integer namespace. @@ -350,9 +351,9 @@ static ssize_t gpio_direction_store(struct device *dev, if (!test_bit(FLAG_EXPORT, &desc->flags)) status = -EIO; else if (sysfs_streq(buf, "high")) - status = gpiod_direction_output(desc, 1); + status = gpiod_direction_output_raw(desc, 1); else if (sysfs_streq(buf, "out") || sysfs_streq(buf, "low")) - status = gpiod_direction_output(desc, 0); + status = gpiod_direction_output_raw(desc, 0); else if (sysfs_streq(buf, "in")) status = gpiod_direction_input(desc); else @@ -1253,6 +1254,9 @@ fail: } EXPORT_SYMBOL_GPL(gpiochip_add); +/* Forward-declaration */ +static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip); + /** * gpiochip_remove() - unregister a gpio_chip * @chip: the chip to unregister @@ -1265,11 +1269,13 @@ int gpiochip_remove(struct gpio_chip *chip) int status = 0; unsigned id; + acpi_gpiochip_remove(chip); + spin_lock_irqsave(&gpio_lock, flags); + gpiochip_irqchip_remove(chip); gpiochip_remove_pin_ranges(chip); of_gpiochip_remove(chip); - acpi_gpiochip_remove(chip); for (id = 0; id < chip->ngpio; id++) { if (test_bit(FLAG_REQUESTED, &chip->desc[id].flags)) { @@ -1337,6 +1343,215 @@ static struct gpio_chip *find_chip_by_name(const char *name) return gpiochip_find((void *)name, gpiochip_match_name); } +#ifdef CONFIG_GPIOLIB_IRQCHIP + +/* + * The following is irqchip helper code for gpiochips. + */ + +/** + * gpiochip_add_chained_irqchip() - adds a chained irqchip to a gpiochip + * @gpiochip: the gpiochip to add the irqchip to + * @irqchip: the irqchip to add to the gpiochip + * @parent_irq: the irq number corresponding to the parent IRQ for this + * chained irqchip + * @parent_handler: the parent interrupt handler for the accumulated IRQ + * coming out of the gpiochip + */ +void gpiochip_set_chained_irqchip(struct gpio_chip *gpiochip, + struct irq_chip *irqchip, + int parent_irq, + irq_flow_handler_t parent_handler) +{ + irq_set_chained_handler(parent_irq, parent_handler); + /* + * 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); +} +EXPORT_SYMBOL_GPL(gpiochip_set_chained_irqchip); + +/** + * gpiochip_irq_map() - maps an IRQ into a GPIO irqchip + * @d: the irqdomain used by this irqchip + * @irq: the global irq number used by this GPIO irqchip irq + * @hwirq: the local IRQ/GPIO line offset on this gpiochip + * + * This function will set up the mapping for a certain IRQ line on a + * gpiochip by assigning the gpiochip as chip data, and using the irqchip + * stored inside the gpiochip. + */ +static int gpiochip_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) +{ + struct gpio_chip *chip = d->host_data; + + irq_set_chip_data(irq, chip); + irq_set_chip_and_handler(irq, chip->irqchip, chip->irq_handler); +#ifdef CONFIG_ARM + set_irq_flags(irq, IRQF_VALID); +#else + irq_set_noprobe(irq); +#endif + irq_set_irq_type(irq, chip->irq_default_type); + + return 0; +} + +static void gpiochip_irq_unmap(struct irq_domain *d, unsigned int irq) +{ +#ifdef CONFIG_ARM + set_irq_flags(irq, 0); +#endif + irq_set_chip_and_handler(irq, NULL, NULL); + irq_set_chip_data(irq, NULL); +} + +static const struct irq_domain_ops gpiochip_domain_ops = { + .map = gpiochip_irq_map, + .unmap = gpiochip_irq_unmap, + /* Virtually all GPIO irqchips are twocell:ed */ + .xlate = irq_domain_xlate_twocell, +}; + +static int gpiochip_irq_reqres(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + + if (gpio_lock_as_irq(chip, d->hwirq)) { + chip_err(chip, + "unable to lock HW IRQ %lu for IRQ\n", + d->hwirq); + return -EINVAL; + } + return 0; +} + +static void gpiochip_irq_relres(struct irq_data *d) +{ + struct gpio_chip *chip = irq_data_get_irq_chip_data(d); + + gpio_unlock_as_irq(chip, d->hwirq); +} + +static int gpiochip_to_irq(struct gpio_chip *chip, unsigned offset) +{ + return irq_find_mapping(chip->irqdomain, offset); +} + +/** + * gpiochip_irqchip_remove() - removes an irqchip added to a gpiochip + * @gpiochip: the gpiochip to remove the irqchip from + * + * This is called only from gpiochip_remove() + */ +static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) +{ + unsigned int offset; + + /* Remove all IRQ mappings and delete the domain */ + if (gpiochip->irqdomain) { + for (offset = 0; offset < gpiochip->ngpio; offset++) + irq_dispose_mapping(gpiochip->irq_base + offset); + irq_domain_remove(gpiochip->irqdomain); + } + + if (gpiochip->irqchip) { + gpiochip->irqchip->irq_request_resources = NULL; + gpiochip->irqchip->irq_release_resources = NULL; + gpiochip->irqchip = NULL; + } +} + +/** + * gpiochip_irqchip_add() - adds an irqchip to a gpiochip + * @gpiochip: the gpiochip to add the irqchip to + * @irqchip: the irqchip to add to the gpiochip + * @first_irq: if not dynamically assigned, the base (first) IRQ to + * allocate gpiochip irqs from + * @handler: the irq handler to use (often a predefined irq core function) + * @type: the default type for IRQs on this irqchip + * + * This function closely associates a certain irqchip with a certain + * gpiochip, providing an irq domain to translate the local IRQs to + * global irqs in the gpiolib core, and making sure that the gpiochip + * is passed as chip data to all related functions. Driver callbacks + * need to use container_of() to get their local state containers back + * from the gpiochip passed as chip data. An irqdomain will be stored + * in the gpiochip that shall be used by the driver to handle IRQ number + * translation. The gpiochip will need to be initialized and registered + * before calling this function. + * + * This function will handle two cell:ed simple IRQs and assumes all + * 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) +{ + struct device_node *of_node; + unsigned int offset; + unsigned irq_base = 0; + + if (!gpiochip || !irqchip) + return -EINVAL; + + if (!gpiochip->dev) { + pr_err("missing gpiochip .dev parent pointer\n"); + return -EINVAL; + } + of_node = gpiochip->dev->of_node; +#ifdef CONFIG_OF_GPIO + /* + * If the gpiochip has an assigned OF node this takes precendence + * FIXME: get rid of this and use gpiochip->dev->of_node everywhere + */ + if (gpiochip->of_node) + of_node = gpiochip->of_node; +#endif + gpiochip->irqchip = irqchip; + gpiochip->irq_handler = handler; + gpiochip->irq_default_type = type; + gpiochip->to_irq = gpiochip_to_irq; + gpiochip->irqdomain = irq_domain_add_simple(of_node, + gpiochip->ngpio, first_irq, + &gpiochip_domain_ops, gpiochip); + if (!gpiochip->irqdomain) { + gpiochip->irqchip = NULL; + return -EINVAL; + } + irqchip->irq_request_resources = gpiochip_irq_reqres; + irqchip->irq_release_resources = gpiochip_irq_relres; + + /* + * Prepare the mapping since the irqchip shall be orthogonal to + * any gpiochip calls. If the first_irq was zero, this is + * necessary to allocate descriptors for all IRQs. + */ + for (offset = 0; offset < gpiochip->ngpio; offset++) { + irq_base = irq_create_mapping(gpiochip->irqdomain, offset); + if (offset == 0) + /* + * Store the base into the gpiochip to be used when + * unmapping the irqs. + */ + gpiochip->irq_base = irq_base; + } + + return 0; +} +EXPORT_SYMBOL_GPL(gpiochip_irqchip_add); + +#else /* CONFIG_GPIOLIB_IRQCHIP */ + +static void gpiochip_irqchip_remove(struct gpio_chip *gpiochip) {} + +#endif /* CONFIG_GPIOLIB_IRQCHIP */ + #ifdef CONFIG_PINCTRL /** @@ -1457,26 +1672,14 @@ EXPORT_SYMBOL_GPL(gpiochip_remove_pin_ranges); * on each other, and help provide better diagnostics in debugfs. * They're called even less than the "set direction" calls. */ -static int gpiod_request(struct gpio_desc *desc, const char *label) +static int __gpiod_request(struct gpio_desc *desc, const char *label) { - struct gpio_chip *chip; - int status = -EPROBE_DEFER; + struct gpio_chip *chip = desc->chip; + int status; unsigned long flags; - if (!desc) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } - spin_lock_irqsave(&gpio_lock, flags); - chip = desc->chip; - if (chip == NULL) - goto done; - - if (!try_module_get(chip->owner)) - goto done; - /* NOTE: gpio_request() can be called in early boot, * before IRQs are enabled, for non-sleeping (SOC) GPIOs. */ @@ -1486,7 +1689,6 @@ static int gpiod_request(struct gpio_desc *desc, const char *label) status = 0; } else { status = -EBUSY; - module_put(chip->owner); goto done; } @@ -1498,7 +1700,6 @@ static int gpiod_request(struct gpio_desc *desc, const char *label) if (status < 0) { desc_set_label(desc, NULL); - module_put(chip->owner); clear_bit(FLAG_REQUESTED, &desc->flags); goto done; } @@ -1510,9 +1711,34 @@ static int gpiod_request(struct gpio_desc *desc, const char *label) spin_lock_irqsave(&gpio_lock, flags); } done: + spin_unlock_irqrestore(&gpio_lock, flags); + return status; +} + +static int gpiod_request(struct gpio_desc *desc, const char *label) +{ + int status = -EPROBE_DEFER; + struct gpio_chip *chip; + + if (!desc) { + pr_warn("%s: invalid GPIO\n", __func__); + return -EINVAL; + } + + chip = desc->chip; + if (!chip) + goto done; + + if (try_module_get(chip->owner)) { + status = __gpiod_request(desc, label); + if (status < 0) + module_put(chip->owner); + } + +done: if (status) gpiod_dbg(desc, "%s: status %d\n", __func__, status); - spin_unlock_irqrestore(&gpio_lock, flags); + return status; } @@ -1522,18 +1748,14 @@ int gpio_request(unsigned gpio, const char *label) } EXPORT_SYMBOL_GPL(gpio_request); -static void gpiod_free(struct gpio_desc *desc) +static bool __gpiod_free(struct gpio_desc *desc) { + bool ret = false; unsigned long flags; struct gpio_chip *chip; might_sleep(); - if (!desc) { - WARN_ON(extra_checks); - return; - } - gpiod_unexport(desc); spin_lock_irqsave(&gpio_lock, flags); @@ -1547,15 +1769,23 @@ static void gpiod_free(struct gpio_desc *desc) spin_lock_irqsave(&gpio_lock, flags); } desc_set_label(desc, NULL); - module_put(desc->chip->owner); clear_bit(FLAG_ACTIVE_LOW, &desc->flags); clear_bit(FLAG_REQUESTED, &desc->flags); clear_bit(FLAG_OPEN_DRAIN, &desc->flags); clear_bit(FLAG_OPEN_SOURCE, &desc->flags); - } else - WARN_ON(extra_checks); + ret = true; + } spin_unlock_irqrestore(&gpio_lock, flags); + return ret; +} + +static void gpiod_free(struct gpio_desc *desc) +{ + if (desc && __gpiod_free(desc)) + module_put(desc->chip->owner); + else + WARN_ON(extra_checks); } void gpio_free(unsigned gpio) @@ -1590,7 +1820,7 @@ int gpio_request_one(unsigned gpio, unsigned long flags, const char *label) if (flags & GPIOF_DIR_IN) err = gpiod_direction_input(desc); else - err = gpiod_direction_output(desc, + err = gpiod_direction_output_raw(desc, (flags & GPIOF_INIT_HIGH) ? 1 : 0); if (err) @@ -1677,6 +1907,37 @@ const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset) } EXPORT_SYMBOL_GPL(gpiochip_is_requested); +/** + * gpiochip_request_own_desc - Allow GPIO chip to request its own descriptor + * @desc: GPIO descriptor to request + * @label: label for the GPIO + * + * Function allows GPIO chip drivers to request and use their own GPIO + * descriptors via gpiolib API. Difference to gpiod_request() is that this + * function will not increase reference count of the GPIO chip module. This + * allows the GPIO chip module to be unloaded as needed (we assume that the + * GPIO chip driver handles freeing the GPIOs it has requested). + */ +int gpiochip_request_own_desc(struct gpio_desc *desc, const char *label) +{ + if (!desc || !desc->chip) + return -EINVAL; + + return __gpiod_request(desc, label); +} + +/** + * gpiochip_free_own_desc - Free GPIO requested by the chip driver + * @desc: GPIO descriptor to free + * + * Function frees the given GPIO requested previously with + * gpiochip_request_own_desc(). + */ +void gpiochip_free_own_desc(struct gpio_desc *desc) +{ + if (desc) + __gpiod_free(desc); +} /* Drivers MUST set GPIO direction before making get/set calls. In * some cases this is done in early boot, before IRQs are enabled. @@ -1756,28 +2017,13 @@ fail: } EXPORT_SYMBOL_GPL(gpiod_direction_input); -/** - * gpiod_direction_output - set the GPIO direction to input - * @desc: GPIO to set to output - * @value: initial output value of the GPIO - * - * Set the direction of the passed GPIO to output, such as gpiod_set_value() can - * be called safely on it. The initial value of the output must be specified. - * - * Return 0 in case of success, else an error code. - */ -int gpiod_direction_output(struct gpio_desc *desc, int value) +static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value) { unsigned long flags; struct gpio_chip *chip; int status = -EINVAL; int offset; - if (!desc || !desc->chip) { - pr_warn("%s: invalid GPIO\n", __func__); - return -EINVAL; - } - /* GPIOs used for IRQs shall not be set as output */ if (test_bit(FLAG_USED_AS_IRQ, &desc->flags)) { gpiod_err(desc, @@ -1840,6 +2086,50 @@ fail: gpiod_dbg(desc, "%s: gpio status %d\n", __func__, status); return status; } + +/** + * gpiod_direction_output_raw - set the GPIO direction to output + * @desc: GPIO to set to output + * @value: initial output value of the GPIO + * + * Set the direction of the passed GPIO to output, such as gpiod_set_value() can + * be called safely on it. The initial value of the output must be specified + * as raw value on the physical line without regard for the ACTIVE_LOW status. + * + * Return 0 in case of success, else an error code. + */ +int gpiod_direction_output_raw(struct gpio_desc *desc, int value) +{ + if (!desc || !desc->chip) { + pr_warn("%s: invalid GPIO\n", __func__); + return -EINVAL; + } + return _gpiod_direction_output_raw(desc, value); +} +EXPORT_SYMBOL_GPL(gpiod_direction_output_raw); + +/** + * gpiod_direction_output - set the GPIO direction to output + * @desc: GPIO to set to output + * @value: initial output value of the GPIO + * + * Set the direction of the passed GPIO to output, such as gpiod_set_value() can + * be called safely on it. The initial value of the output must be specified + * as the logical value of the GPIO, i.e. taking its ACTIVE_LOW status into + * account. + * + * Return 0 in case of success, else an error code. + */ +int gpiod_direction_output(struct gpio_desc *desc, int value) +{ + if (!desc || !desc->chip) { + pr_warn("%s: invalid GPIO\n", __func__); + return -EINVAL; + } + if (test_bit(FLAG_ACTIVE_LOW, &desc->flags)) + value = !value; + return _gpiod_direction_output_raw(desc, value); +} EXPORT_SYMBOL_GPL(gpiod_direction_output); /** @@ -1928,15 +2218,15 @@ EXPORT_SYMBOL_GPL(gpiod_is_active_low); * that the GPIO was actually requested. */ -static int _gpiod_get_raw_value(const struct gpio_desc *desc) +static bool _gpiod_get_raw_value(const struct gpio_desc *desc) { struct gpio_chip *chip; - int value; + bool value; int offset; chip = desc->chip; offset = gpio_chip_hwgpio(desc); - value = chip->get ? chip->get(chip, offset) : 0; + value = chip->get ? chip->get(chip, offset) : false; trace_gpio_value(desc_to_gpio(desc), 1, value); return value; } @@ -1992,7 +2282,7 @@ EXPORT_SYMBOL_GPL(gpiod_get_value); * @desc: gpio descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherise it will set to LOW. */ -static void _gpio_set_open_drain_value(struct gpio_desc *desc, int value) +static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value) { int err = 0; struct gpio_chip *chip = desc->chip; @@ -2019,7 +2309,7 @@ static void _gpio_set_open_drain_value(struct gpio_desc *desc, int value) * @desc: gpio descriptor whose state need to be set. * @value: Non-zero for setting it HIGH otherise it will set to LOW. */ -static void _gpio_set_open_source_value(struct gpio_desc *desc, int value) +static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value) { int err = 0; struct gpio_chip *chip = desc->chip; @@ -2041,7 +2331,7 @@ static void _gpio_set_open_source_value(struct gpio_desc *desc, int value) __func__, err); } -static void _gpiod_set_raw_value(struct gpio_desc *desc, int value) +static void _gpiod_set_raw_value(struct gpio_desc *desc, bool value) { struct gpio_chip *chip; @@ -2137,10 +2427,7 @@ EXPORT_SYMBOL_GPL(gpiod_to_irq); * @gpio: the GPIO line to lock as used for IRQ * * This is used directly by GPIO drivers that want to lock down - * a certain GPIO line to be used as IRQs, for example in the - * .to_irq() callback of their gpio_chip, or in the .irq_enable() - * of its irq_chip implementation if the GPIO is known from that - * code. + * a certain GPIO line to be used for IRQs. */ int gpiod_lock_as_irq(struct gpio_desc *desc) { @@ -2161,7 +2448,7 @@ EXPORT_SYMBOL_GPL(gpiod_lock_as_irq); int gpio_lock_as_irq(struct gpio_chip *chip, unsigned int offset) { - return gpiod_lock_as_irq(gpiochip_offset_to_desc(chip, offset)); + return gpiod_lock_as_irq(gpiochip_get_desc(chip, offset)); } EXPORT_SYMBOL_GPL(gpio_lock_as_irq); @@ -2183,7 +2470,7 @@ EXPORT_SYMBOL_GPL(gpiod_unlock_as_irq); void gpio_unlock_as_irq(struct gpio_chip *chip, unsigned int offset) { - return gpiod_unlock_as_irq(gpiochip_offset_to_desc(chip, offset)); + return gpiod_unlock_as_irq(gpiochip_get_desc(chip, offset)); } EXPORT_SYMBOL_GPL(gpio_unlock_as_irq); @@ -2404,7 +2691,7 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id, return ERR_PTR(-EINVAL); } - desc = gpiochip_offset_to_desc(chip, p->chip_hwnum); + desc = gpiochip_get_desc(chip, p->chip_hwnum); *flags = p->flags; return desc; |