diff options
Diffstat (limited to 'drivers/gpio')
| -rw-r--r-- | drivers/gpio/devres.c | 32 | ||||
| -rw-r--r-- | drivers/gpio/gpio-omap.c | 8 | ||||
| -rw-r--r-- | drivers/gpio/gpio-sch.c | 293 | ||||
| -rw-r--r-- | drivers/gpio/gpio-zynq.c | 2 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib-acpi.c | 117 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.c | 85 | ||||
| -rw-r--r-- | drivers/gpio/gpiolib.h | 7 |
7 files changed, 337 insertions, 207 deletions
diff --git a/drivers/gpio/devres.c b/drivers/gpio/devres.c index 954b9f6b0ef..13dbd3dfc33 100644 --- a/drivers/gpio/devres.c +++ b/drivers/gpio/devres.c @@ -109,6 +109,38 @@ struct gpio_desc *__must_check __devm_gpiod_get_index(struct device *dev, EXPORT_SYMBOL(__devm_gpiod_get_index); /** + * devm_get_gpiod_from_child - get a GPIO descriptor from a device's child node + * @dev: GPIO consumer + * @child: firmware node (child of @dev) + * + * GPIO descriptors returned from this function are automatically disposed on + * driver detach. + */ +struct gpio_desc *devm_get_gpiod_from_child(struct device *dev, + struct fwnode_handle *child) +{ + struct gpio_desc **dr; + struct gpio_desc *desc; + + dr = devres_alloc(devm_gpiod_release, sizeof(struct gpio_desc *), + GFP_KERNEL); + if (!dr) + return ERR_PTR(-ENOMEM); + + desc = fwnode_get_named_gpiod(child, "gpios"); + if (IS_ERR(desc)) { + devres_free(dr); + return desc; + } + + *dr = desc; + devres_add(dev, dr); + + return desc; +} +EXPORT_SYMBOL(devm_get_gpiod_from_child); + +/** * devm_gpiod_get_index_optional - Resource-managed gpiod_get_index_optional() * @dev: GPIO consumer * @con_id: function within the GPIO consumer diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c index 415682f6921..3d6b445665a 100644 --- a/drivers/gpio/gpio-omap.c +++ b/drivers/gpio/gpio-omap.c @@ -1259,7 +1259,7 @@ static int omap_gpio_probe(struct platform_device *pdev) #ifdef CONFIG_ARCH_OMAP2PLUS -#if defined(CONFIG_PM_RUNTIME) +#if defined(CONFIG_PM) static void omap_gpio_restore_context(struct gpio_bank *bank); static int omap_gpio_runtime_suspend(struct device *dev) @@ -1440,7 +1440,7 @@ static int omap_gpio_runtime_resume(struct device *dev) return 0; } -#endif /* CONFIG_PM_RUNTIME */ +#endif /* CONFIG_PM */ void omap2_gpio_prepare_for_idle(int pwr_mode) { @@ -1468,7 +1468,7 @@ void omap2_gpio_resume_after_idle(void) } } -#if defined(CONFIG_PM_RUNTIME) +#if defined(CONFIG_PM) static void omap_gpio_init_context(struct gpio_bank *p) { struct omap_gpio_reg_offs *regs = p->regs; @@ -1525,7 +1525,7 @@ static void omap_gpio_restore_context(struct gpio_bank *bank) writel_relaxed(bank->context.irqenable2, bank->base + bank->regs->irqenable2); } -#endif /* CONFIG_PM_RUNTIME */ +#endif /* CONFIG_PM */ #else #define omap_gpio_runtime_suspend NULL #define omap_gpio_runtime_resume NULL diff --git a/drivers/gpio/gpio-sch.c b/drivers/gpio/gpio-sch.c index 41e91d70301..99720c8bc8e 100644 --- a/drivers/gpio/gpio-sch.c +++ b/drivers/gpio/gpio-sch.c @@ -29,290 +29,221 @@ #include <linux/gpio.h> -static DEFINE_SPINLOCK(gpio_lock); - -#define CGEN (0x00) -#define CGIO (0x04) -#define CGLV (0x08) - -#define RGEN (0x20) -#define RGIO (0x24) -#define RGLV (0x28) - -static unsigned short gpio_ba; - -static int sch_gpio_core_direction_in(struct gpio_chip *gc, unsigned gpio_num) -{ - u8 curr_dirs; - unsigned short offset, bit; - - spin_lock(&gpio_lock); - - offset = CGIO + gpio_num / 8; - bit = gpio_num % 8; - - curr_dirs = inb(gpio_ba + offset); - - if (!(curr_dirs & (1 << bit))) - outb(curr_dirs | (1 << bit), gpio_ba + offset); +#define GEN 0x00 +#define GIO 0x04 +#define GLV 0x08 + +struct sch_gpio { + struct gpio_chip chip; + spinlock_t lock; + unsigned short iobase; + unsigned short core_base; + unsigned short resume_base; +}; - spin_unlock(&gpio_lock); - return 0; -} +#define to_sch_gpio(c) container_of(c, struct sch_gpio, chip) -static int sch_gpio_core_get(struct gpio_chip *gc, unsigned gpio_num) +static unsigned sch_gpio_offset(struct sch_gpio *sch, unsigned gpio, + unsigned reg) { - int res; - unsigned short offset, bit; + unsigned base = 0; - offset = CGLV + gpio_num / 8; - bit = gpio_num % 8; + if (gpio >= sch->resume_base) { + gpio -= sch->resume_base; + base += 0x20; + } - res = !!(inb(gpio_ba + offset) & (1 << bit)); - return res; + return base + reg + gpio / 8; } -static void sch_gpio_core_set(struct gpio_chip *gc, unsigned gpio_num, int val) +static unsigned sch_gpio_bit(struct sch_gpio *sch, unsigned gpio) { - u8 curr_vals; - unsigned short offset, bit; - - spin_lock(&gpio_lock); - - offset = CGLV + gpio_num / 8; - bit = gpio_num % 8; - - curr_vals = inb(gpio_ba + offset); - - if (val) - outb(curr_vals | (1 << bit), gpio_ba + offset); - else - outb((curr_vals & ~(1 << bit)), gpio_ba + offset); - spin_unlock(&gpio_lock); + if (gpio >= sch->resume_base) + gpio -= sch->resume_base; + return gpio % 8; } -static int sch_gpio_core_direction_out(struct gpio_chip *gc, - unsigned gpio_num, int val) +static void sch_gpio_enable(struct sch_gpio *sch, unsigned gpio) { - u8 curr_dirs; unsigned short offset, bit; + u8 enable; - spin_lock(&gpio_lock); + spin_lock(&sch->lock); - offset = CGIO + gpio_num / 8; - bit = gpio_num % 8; - - curr_dirs = inb(gpio_ba + offset); - if (curr_dirs & (1 << bit)) - outb(curr_dirs & ~(1 << bit), gpio_ba + offset); + offset = sch_gpio_offset(sch, gpio, GEN); + bit = sch_gpio_bit(sch, gpio); - spin_unlock(&gpio_lock); + enable = inb(sch->iobase + offset); + if (!(enable & (1 << bit))) + outb(enable | (1 << bit), sch->iobase + offset); - /* - * according to the datasheet, writing to the level register has no - * effect when GPIO is programmed as input. - * Actually the the level register is read-only when configured as input. - * Thus presetting the output level before switching to output is _NOT_ possible. - * Hence we set the level after configuring the GPIO as output. - * But we cannot prevent a short low pulse if direction is set to high - * and an external pull-up is connected. - */ - sch_gpio_core_set(gc, gpio_num, val); - return 0; + spin_unlock(&sch->lock); } -static struct gpio_chip sch_gpio_core = { - .label = "sch_gpio_core", - .owner = THIS_MODULE, - .direction_input = sch_gpio_core_direction_in, - .get = sch_gpio_core_get, - .direction_output = sch_gpio_core_direction_out, - .set = sch_gpio_core_set, -}; - -static int sch_gpio_resume_direction_in(struct gpio_chip *gc, - unsigned gpio_num) +static int sch_gpio_direction_in(struct gpio_chip *gc, unsigned gpio_num) { + struct sch_gpio *sch = to_sch_gpio(gc); u8 curr_dirs; unsigned short offset, bit; - spin_lock(&gpio_lock); + spin_lock(&sch->lock); - offset = RGIO + gpio_num / 8; - bit = gpio_num % 8; + offset = sch_gpio_offset(sch, gpio_num, GIO); + bit = sch_gpio_bit(sch, gpio_num); - curr_dirs = inb(gpio_ba + offset); + curr_dirs = inb(sch->iobase + offset); if (!(curr_dirs & (1 << bit))) - outb(curr_dirs | (1 << bit), gpio_ba + offset); + outb(curr_dirs | (1 << bit), sch->iobase + offset); - spin_unlock(&gpio_lock); + spin_unlock(&sch->lock); return 0; } -static int sch_gpio_resume_get(struct gpio_chip *gc, unsigned gpio_num) +static int sch_gpio_get(struct gpio_chip *gc, unsigned gpio_num) { + struct sch_gpio *sch = to_sch_gpio(gc); + int res; unsigned short offset, bit; - offset = RGLV + gpio_num / 8; - bit = gpio_num % 8; + offset = sch_gpio_offset(sch, gpio_num, GLV); + bit = sch_gpio_bit(sch, gpio_num); + + res = !!(inb(sch->iobase + offset) & (1 << bit)); - return !!(inb(gpio_ba + offset) & (1 << bit)); + return res; } -static void sch_gpio_resume_set(struct gpio_chip *gc, - unsigned gpio_num, int val) +static void sch_gpio_set(struct gpio_chip *gc, unsigned gpio_num, int val) { + struct sch_gpio *sch = to_sch_gpio(gc); u8 curr_vals; unsigned short offset, bit; - spin_lock(&gpio_lock); + spin_lock(&sch->lock); - offset = RGLV + gpio_num / 8; - bit = gpio_num % 8; + offset = sch_gpio_offset(sch, gpio_num, GLV); + bit = sch_gpio_bit(sch, gpio_num); - curr_vals = inb(gpio_ba + offset); + curr_vals = inb(sch->iobase + offset); if (val) - outb(curr_vals | (1 << bit), gpio_ba + offset); + outb(curr_vals | (1 << bit), sch->iobase + offset); else - outb((curr_vals & ~(1 << bit)), gpio_ba + offset); + outb((curr_vals & ~(1 << bit)), sch->iobase + offset); - spin_unlock(&gpio_lock); + spin_unlock(&sch->lock); } -static int sch_gpio_resume_direction_out(struct gpio_chip *gc, - unsigned gpio_num, int val) +static int sch_gpio_direction_out(struct gpio_chip *gc, unsigned gpio_num, + int val) { + struct sch_gpio *sch = to_sch_gpio(gc); u8 curr_dirs; unsigned short offset, bit; - offset = RGIO + gpio_num / 8; - bit = gpio_num % 8; + spin_lock(&sch->lock); - spin_lock(&gpio_lock); + offset = sch_gpio_offset(sch, gpio_num, GIO); + bit = sch_gpio_bit(sch, gpio_num); - curr_dirs = inb(gpio_ba + offset); + curr_dirs = inb(sch->iobase + offset); if (curr_dirs & (1 << bit)) - outb(curr_dirs & ~(1 << bit), gpio_ba + offset); + outb(curr_dirs & ~(1 << bit), sch->iobase + offset); - spin_unlock(&gpio_lock); + spin_unlock(&sch->lock); /* - * according to the datasheet, writing to the level register has no - * effect when GPIO is programmed as input. - * Actually the the level register is read-only when configured as input. - * Thus presetting the output level before switching to output is _NOT_ possible. - * Hence we set the level after configuring the GPIO as output. - * But we cannot prevent a short low pulse if direction is set to high - * and an external pull-up is connected. - */ - sch_gpio_resume_set(gc, gpio_num, val); + * according to the datasheet, writing to the level register has no + * effect when GPIO is programmed as input. + * Actually the the level register is read-only when configured as input. + * Thus presetting the output level before switching to output is _NOT_ possible. + * Hence we set the level after configuring the GPIO as output. + * But we cannot prevent a short low pulse if direction is set to high + * and an external pull-up is connected. + */ + sch_gpio_set(gc, gpio_num, val); return 0; } -static struct gpio_chip sch_gpio_resume = { - .label = "sch_gpio_resume", +static struct gpio_chip sch_gpio_chip = { + .label = "sch_gpio", .owner = THIS_MODULE, - .direction_input = sch_gpio_resume_direction_in, - .get = sch_gpio_resume_get, - .direction_output = sch_gpio_resume_direction_out, - .set = sch_gpio_resume_set, + .direction_input = sch_gpio_direction_in, + .get = sch_gpio_get, + .direction_output = sch_gpio_direction_out, + .set = sch_gpio_set, }; static int sch_gpio_probe(struct platform_device *pdev) { + struct sch_gpio *sch; struct resource *res; - int err, id; - id = pdev->id; - if (!id) - return -ENODEV; + sch = devm_kzalloc(&pdev->dev, sizeof(*sch), GFP_KERNEL); + if (!sch) + return -ENOMEM; res = platform_get_resource(pdev, IORESOURCE_IO, 0); if (!res) return -EBUSY; - if (!request_region(res->start, resource_size(res), pdev->name)) + if (!devm_request_region(&pdev->dev, res->start, resource_size(res), + pdev->name)) return -EBUSY; - gpio_ba = res->start; + spin_lock_init(&sch->lock); + sch->iobase = res->start; + sch->chip = sch_gpio_chip; + sch->chip.label = dev_name(&pdev->dev); + sch->chip.dev = &pdev->dev; - switch (id) { + switch (pdev->id) { case PCI_DEVICE_ID_INTEL_SCH_LPC: - sch_gpio_core.base = 0; - sch_gpio_core.ngpio = 10; - sch_gpio_resume.base = 10; - sch_gpio_resume.ngpio = 4; + sch->core_base = 0; + sch->resume_base = 10; + sch->chip.ngpio = 14; + /* * GPIO[6:0] enabled by default * GPIO7 is configured by the CMC as SLPIOVR * Enable GPIO[9:8] core powered gpios explicitly */ - outb(0x3, gpio_ba + CGEN + 1); + sch_gpio_enable(sch, 8); + sch_gpio_enable(sch, 9); /* * SUS_GPIO[2:0] enabled by default * Enable SUS_GPIO3 resume powered gpio explicitly */ - outb(0x8, gpio_ba + RGEN); + sch_gpio_enable(sch, 13); break; case PCI_DEVICE_ID_INTEL_ITC_LPC: - sch_gpio_core.base = 0; - sch_gpio_core.ngpio = 5; - sch_gpio_resume.base = 5; - sch_gpio_resume.ngpio = 9; + sch->core_base = 0; + sch->resume_base = 5; + sch->chip.ngpio = 14; break; case PCI_DEVICE_ID_INTEL_CENTERTON_ILB: - sch_gpio_core.base = 0; - sch_gpio_core.ngpio = 21; - sch_gpio_resume.base = 21; - sch_gpio_resume.ngpio = 9; + sch->core_base = 0; + sch->resume_base = 21; + sch->chip.ngpio = 30; break; default: - err = -ENODEV; - goto err_sch_gpio_core; + return -ENODEV; } - sch_gpio_core.dev = &pdev->dev; - sch_gpio_resume.dev = &pdev->dev; - - err = gpiochip_add(&sch_gpio_core); - if (err < 0) - goto err_sch_gpio_core; + platform_set_drvdata(pdev, sch); - err = gpiochip_add(&sch_gpio_resume); - if (err < 0) - goto err_sch_gpio_resume; - - return 0; - -err_sch_gpio_resume: - gpiochip_remove(&sch_gpio_core); - -err_sch_gpio_core: - release_region(res->start, resource_size(res)); - gpio_ba = 0; - - return err; + return gpiochip_add(&sch->chip); } static int sch_gpio_remove(struct platform_device *pdev) { - struct resource *res; - if (gpio_ba) { - - gpiochip_remove(&sch_gpio_core); - gpiochip_remove(&sch_gpio_resume); - - res = platform_get_resource(pdev, IORESOURCE_IO, 0); - - release_region(res->start, resource_size(res)); - gpio_ba = 0; - } + struct sch_gpio *sch = platform_get_drvdata(pdev); + gpiochip_remove(&sch->chip); return 0; } diff --git a/drivers/gpio/gpio-zynq.c b/drivers/gpio/gpio-zynq.c index 74cd480bf8d..184c4b1b255 100644 --- a/drivers/gpio/gpio-zynq.c +++ b/drivers/gpio/gpio-zynq.c @@ -578,7 +578,7 @@ static void zynq_gpio_free(struct gpio_chip *chip, unsigned offset) static const struct dev_pm_ops zynq_gpio_dev_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(zynq_gpio_suspend, zynq_gpio_resume) - SET_PM_RUNTIME_PM_OPS(zynq_gpio_runtime_suspend, + SET_RUNTIME_PM_OPS(zynq_gpio_runtime_suspend, zynq_gpio_runtime_resume, NULL) }; diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 05c6275da22..ba98bb59a58 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -287,9 +287,45 @@ void acpi_gpiochip_free_interrupts(struct gpio_chip *chip) } } +int acpi_dev_add_driver_gpios(struct acpi_device *adev, + const struct acpi_gpio_mapping *gpios) +{ + if (adev && gpios) { + adev->driver_gpios = gpios; + return 0; + } + return -EINVAL; +} +EXPORT_SYMBOL_GPL(acpi_dev_add_driver_gpios); + +static bool acpi_get_driver_gpio_data(struct acpi_device *adev, + const char *name, int index, + struct acpi_reference_args *args) +{ + const struct acpi_gpio_mapping *gm; + + if (!adev->driver_gpios) + return false; + + for (gm = adev->driver_gpios; gm->name; gm++) + if (!strcmp(name, gm->name) && gm->data && index < gm->size) { + const struct acpi_gpio_params *par = gm->data + index; + + args->adev = adev; + args->args[0] = par->crs_entry_index; + args->args[1] = par->line_index; + args->args[2] = par->active_low; + args->nargs = 3; + return true; + } + + return false; +} + struct acpi_gpio_lookup { struct acpi_gpio_info info; int index; + int pin_index; struct gpio_desc *desc; int n; }; @@ -303,13 +339,24 @@ static int acpi_find_gpio(struct acpi_resource *ares, void *data) if (lookup->n++ == lookup->index && !lookup->desc) { const struct acpi_resource_gpio *agpio = &ares->data.gpio; + int pin_index = lookup->pin_index; + + if (pin_index >= agpio->pin_table_length) + return 1; lookup->desc = acpi_get_gpiod(agpio->resource_source.string_ptr, - agpio->pin_table[0]); + agpio->pin_table[pin_index]); lookup->info.gpioint = agpio->connection_type == ACPI_RESOURCE_GPIO_TYPE_INT; - lookup->info.active_low = - agpio->polarity == ACPI_ACTIVE_LOW; + + /* + * ActiveLow is only specified for GpioInt resource. If + * GpioIo is used then the only way to set the flag is + * to use _DSD "gpios" property. + */ + if (lookup->info.gpioint) + lookup->info.active_low = + agpio->polarity == ACPI_ACTIVE_LOW; } return 1; @@ -317,40 +364,79 @@ static int acpi_find_gpio(struct acpi_resource *ares, void *data) /** * acpi_get_gpiod_by_index() - get a GPIO descriptor from device resources - * @dev: pointer to a device to get GPIO from + * @adev: pointer to a ACPI device to get GPIO from + * @propname: Property name of the GPIO (optional) * @index: index of GpioIo/GpioInt resource (starting from %0) * @info: info pointer to fill in (optional) * - * Function goes through ACPI resources for @dev and based on @index looks + * Function goes through ACPI resources for @adev and based on @index looks * up a GpioIo/GpioInt resource, translates it to the Linux GPIO descriptor, * and returns it. @index matches GpioIo/GpioInt resources only so if there * are total %3 GPIO resources, the index goes from %0 to %2. * + * If @propname is specified the GPIO is looked using device property. In + * that case @index is used to select the GPIO entry in the property value + * (in case of multiple). + * * If the GPIO cannot be translated or there is an error an ERR_PTR is * returned. * * Note: if the GPIO resource has multiple entries in the pin list, this * function only returns the first. */ -struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index, +struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, + const char *propname, int index, struct acpi_gpio_info *info) { struct acpi_gpio_lookup lookup; struct list_head resource_list; - struct acpi_device *adev; - acpi_handle handle; + bool active_low = false; int ret; - if (!dev) - return ERR_PTR(-EINVAL); - - handle = ACPI_HANDLE(dev); - if (!handle || acpi_bus_get_device(handle, &adev)) + if (!adev) return ERR_PTR(-ENODEV); memset(&lookup, 0, sizeof(lookup)); lookup.index = index; + if (propname) { + struct acpi_reference_args args; + + dev_dbg(&adev->dev, "GPIO: looking up %s\n", propname); + + memset(&args, 0, sizeof(args)); + ret = acpi_dev_get_property_reference(adev, propname, + index, &args); + if (ret) { + bool found = acpi_get_driver_gpio_data(adev, propname, + index, &args); + if (!found) + return ERR_PTR(ret); + } + + /* + * The property was found and resolved so need to + * lookup the GPIO based on returned args instead. + */ + adev = args.adev; + if (args.nargs >= 2) { + lookup.index = args.args[0]; + lookup.pin_index = args.args[1]; + /* + * 3rd argument, if present is used to + * specify active_low. + */ + if (args.nargs >= 3) + active_low = !!args.args[2]; + } + + dev_dbg(&adev->dev, "GPIO: _DSD returned %s %zd %llu %llu %llu\n", + dev_name(&adev->dev), args.nargs, + args.args[0], args.args[1], args.args[2]); + } else { + dev_dbg(&adev->dev, "GPIO: looking up %d in _CRS\n", index); + } + INIT_LIST_HEAD(&resource_list); ret = acpi_dev_get_resources(adev, &resource_list, acpi_find_gpio, &lookup); @@ -359,8 +445,11 @@ struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index, acpi_dev_free_resource_list(&resource_list); - if (lookup.desc && info) + if (lookup.desc && info) { *info = lookup.info; + if (active_low) + info->active_low = active_low; + } return lookup.desc ? lookup.desc : ERR_PTR(-ENOENT); } diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index e8e98ca25ec..58659dbe702 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1505,14 +1505,36 @@ 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; + char propname[32]; + int i; - desc = acpi_get_gpiod_by_index(dev, idx, &info); - if (IS_ERR(desc)) - return desc; + /* Try first from _DSD */ + for (i = 0; i < ARRAY_SIZE(suffixes); i++) { + if (con_id && strcmp(con_id, "gpios")) { + snprintf(propname, sizeof(propname), "%s-%s", + con_id, suffixes[i]); + } else { + snprintf(propname, sizeof(propname), "%s", + suffixes[i]); + } + + desc = acpi_get_gpiod_by_index(adev, propname, idx, &info); + if (!IS_ERR(desc) || (PTR_ERR(desc) == -EPROBE_DEFER)) + break; + } - if (info.gpioint && info.active_low) + /* Then from plain _CRS GPIOs */ + if (IS_ERR(desc)) { + desc = acpi_get_gpiod_by_index(adev, NULL, idx, &info); + if (IS_ERR(desc)) + return desc; + } + + if (info.active_low) *flags |= GPIO_ACTIVE_LOW; return desc; @@ -1713,6 +1735,61 @@ struct gpio_desc *__must_check __gpiod_get_index(struct device *dev, EXPORT_SYMBOL_GPL(__gpiod_get_index); /** + * fwnode_get_named_gpiod - obtain a GPIO from firmware node + * @fwnode: handle of the firmware node + * @propname: name of the firmware property representing the GPIO + * + * This function can be used for drivers that get their configuration + * from firmware. + * + * Function properly finds the corresponding GPIO using whatever is the + * underlying firmware interface and then makes sure that the GPIO + * descriptor is requested before it is returned to the caller. + * + * In case of error an ERR_PTR() is returned. + */ +struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, + const char *propname) +{ + struct gpio_desc *desc = ERR_PTR(-ENODEV); + bool active_low = false; + int ret; + + if (!fwnode) + return ERR_PTR(-EINVAL); + + if (is_of_node(fwnode)) { + enum of_gpio_flags flags; + + desc = of_get_named_gpiod_flags(of_node(fwnode), propname, 0, + &flags); + if (!IS_ERR(desc)) + active_low = flags & OF_GPIO_ACTIVE_LOW; + } else if (is_acpi_node(fwnode)) { + struct acpi_gpio_info info; + + desc = acpi_get_gpiod_by_index(acpi_node(fwnode), propname, 0, + &info); + if (!IS_ERR(desc)) + active_low = info.active_low; + } + + if (IS_ERR(desc)) + return desc; + + ret = gpiod_request(desc, NULL); + if (ret) + return ERR_PTR(ret); + + /* Only value flag can be set from both DT and ACPI is active_low */ + if (active_low) + set_bit(FLAG_ACTIVE_LOW, &desc->flags); + + return desc; +} +EXPORT_SYMBOL_GPL(fwnode_get_named_gpiod); + +/** * gpiod_get_index_optional - obtain an optional GPIO from a multi-index GPIO * function * @dev: GPIO consumer, can be NULL for system-global GPIOs diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h index 9db2b6a71c5..e3a52113a54 100644 --- a/drivers/gpio/gpiolib.h +++ b/drivers/gpio/gpiolib.h @@ -34,7 +34,8 @@ void acpi_gpiochip_remove(struct gpio_chip *chip); void acpi_gpiochip_request_interrupts(struct gpio_chip *chip); void acpi_gpiochip_free_interrupts(struct gpio_chip *chip); -struct gpio_desc *acpi_get_gpiod_by_index(struct device *dev, int index, +struct gpio_desc *acpi_get_gpiod_by_index(struct acpi_device *adev, + const char *propname, int index, struct acpi_gpio_info *info); #else static inline void acpi_gpiochip_add(struct gpio_chip *chip) { } @@ -47,8 +48,8 @@ static inline void acpi_gpiochip_free_interrupts(struct gpio_chip *chip) { } static inline struct gpio_desc * -acpi_get_gpiod_by_index(struct device *dev, int index, - struct acpi_gpio_info *info) +acpi_get_gpiod_by_index(struct acpi_device *adev, const char *propname, + int index, struct acpi_gpio_info *info) { return ERR_PTR(-ENOSYS); } |