From 8eb1f71e7acca4f92cf9cf83030cbb8ec2524025 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Fri, 11 Nov 2022 14:19:07 -0800 Subject: [PATCH] gpiolib: consolidate GPIO lookups Ensure that all paths to obtain/look up GPIOD from generic consumer-visible APIs go through the new gpiod_find_and_request() helper, so that we can easily extend it with support for new firmware mechanisms. The only exception is OF-specific [devm_]gpiod_get_from_of_node() API that is still being used by a couple of drivers and will be removed as soon as patches converting them to use generic fwnode/device APIs are accepted. Acked-by: Linus Walleij Signed-off-by: Dmitry Torokhov Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpiolib-acpi.c | 39 --------- drivers/gpio/gpiolib-acpi.h | 10 --- drivers/gpio/gpiolib.c | 204 +++++++++++++++++--------------------------- 3 files changed, 76 insertions(+), 177 deletions(-) diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 1d69b70..c99c94e 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -1025,45 +1025,6 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode, } /** - * acpi_node_get_gpiod() - get a GPIO descriptor from ACPI resources - * @fwnode: pointer to an ACPI firmware node to get the GPIO information from - * @propname: Property name of the GPIO - * @index: index of GpioIo/GpioInt resource (starting from %0) - * @lflags: bitmask of gpio_lookup_flags GPIO_* values - * @dflags: gpiod initialization flags - * - * If @fwnode is an ACPI device object, call acpi_get_gpiod_by_index() for it. - * Otherwise (i.e. it is a data-only non-device object), use the property-based - * GPIO lookup to get to the GPIO resource with the relevant information and use - * that to obtain the GPIO descriptor to return. - * - * If the GPIO cannot be translated or there is an error an ERR_PTR is - * returned. - */ -struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode, - const char *propname, int index, - unsigned long *lflags, - enum gpiod_flags *dflags) -{ - struct acpi_gpio_info info; - struct acpi_device *adev; - struct gpio_desc *desc; - - adev = to_acpi_device_node(fwnode); - if (adev) - desc = acpi_get_gpiod_by_index(adev, propname, index, &info); - else - desc = acpi_get_gpiod_from_data(fwnode, propname, index, &info); - - if (!IS_ERR(desc)) { - acpi_gpio_update_gpiod_flags(dflags, &info); - acpi_gpio_update_gpiod_lookup_flags(lflags, &info); - } - - return desc; -} - -/** * acpi_dev_gpio_irq_wake_get_by() - Find GpioInt and translate it to Linux IRQ number * @adev: pointer to a ACPI device to get IRQ from * @name: optional name of GpioInt resource diff --git a/drivers/gpio/gpiolib-acpi.h b/drivers/gpio/gpiolib-acpi.h index 42adaab..d2b5dab 100644 --- a/drivers/gpio/gpiolib-acpi.h +++ b/drivers/gpio/gpiolib-acpi.h @@ -24,10 +24,6 @@ struct gpio_desc *acpi_find_gpio(struct fwnode_handle *fwnode, unsigned int idx, enum gpiod_flags *dflags, unsigned long *lookupflags); -struct gpio_desc *acpi_node_get_gpiod(struct fwnode_handle *fwnode, - const char *propname, int index, - unsigned long *lflags, - enum gpiod_flags *dflags); int acpi_gpio_count(struct device *dev, const char *con_id); #else @@ -49,12 +45,6 @@ acpi_find_gpio(struct fwnode_handle *fwnode, const char *con_id, { return ERR_PTR(-ENOENT); } -static inline struct gpio_desc * -acpi_node_get_gpiod(struct fwnode_handle *fwnode, const char *propname, - int index, unsigned long *lflags, enum gpiod_flags *dflags) -{ - return ERR_PTR(-ENXIO); -} static inline int acpi_gpio_count(struct device *dev, const char *con_id) { return -ENODEV; diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index b213f5f9..7f73909 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -366,7 +366,7 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc) static int devprop_gpiochip_set_names(struct gpio_chip *chip) { struct gpio_device *gdev = chip->gpiodev; - struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); + const struct fwnode_handle *fwnode = dev_fwnode(&gdev->dev); const char **names; int ret, i; int count; @@ -3853,58 +3853,84 @@ static int platform_gpio_count(struct device *dev, const char *con_id) return count; } -/** - * 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 - * @index: index of the GPIO to obtain for the consumer - * @dflags: GPIO initialization flags - * @label: label to attach to the requested GPIO - * - * This function can be used for drivers that get their configuration - * from opaque firmware. - * - * The 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. - * - * Returns: - * On successful request the GPIO pin is configured in accordance with - * provided @dflags. - * - * In case of error an ERR_PTR() is returned. - */ -static struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, - const char *propname, int index, - enum gpiod_flags dflags, - const char *label) +static struct gpio_desc *gpiod_find_by_fwnode(struct fwnode_handle *fwnode, + struct device *consumer, + const char *con_id, + unsigned int idx, + enum gpiod_flags *flags, + unsigned long *lookupflags) { - unsigned long lflags = GPIO_LOOKUP_FLAGS_DEFAULT; - struct gpio_desc *desc = ERR_PTR(-ENODEV); - int ret; + struct gpio_desc *desc = ERR_PTR(-ENOENT); if (is_of_node(fwnode)) { - desc = gpiod_get_from_of_node(to_of_node(fwnode), - propname, index, - dflags, - label); - return desc; + dev_dbg(consumer, "using DT '%pfw' for '%s' GPIO lookup\n", + fwnode, con_id); + desc = of_find_gpio(to_of_node(fwnode), con_id, idx, lookupflags); } else if (is_acpi_node(fwnode)) { - desc = acpi_node_get_gpiod(fwnode, propname, index, - &lflags, &dflags); - if (IS_ERR(desc)) - return desc; - } else { - return ERR_PTR(-EINVAL); + dev_dbg(consumer, "using ACPI '%pfw' for '%s' GPIO lookup\n", + fwnode, con_id); + desc = acpi_find_gpio(fwnode, con_id, idx, flags, lookupflags); } - /* Currently only ACPI takes this path */ + return desc; +} + +static struct gpio_desc *gpiod_find_and_request(struct device *consumer, + struct fwnode_handle *fwnode, + const char *con_id, + unsigned int idx, + enum gpiod_flags flags, + const char *label, + bool platform_lookup_allowed) +{ + struct gpio_desc *desc = ERR_PTR(-ENOENT); + unsigned long lookupflags; + int ret; + + if (!IS_ERR_OR_NULL(fwnode)) + desc = gpiod_find_by_fwnode(fwnode, consumer, con_id, idx, + &flags, &lookupflags); + + if (gpiod_not_found(desc) && platform_lookup_allowed) { + /* + * Either we are not using DT or ACPI, or their lookup did not + * return a result. In that case, use platform lookup as a + * fallback. + */ + dev_dbg(consumer, "using lookup tables for GPIO lookup\n"); + desc = gpiod_find(consumer, con_id, idx, &lookupflags); + } + + if (IS_ERR(desc)) { + dev_dbg(consumer, "No GPIO consumer %s found\n", con_id); + return desc; + } + + /* + * If a connection label was passed use that, else attempt to use + * the device name as label + */ ret = gpiod_request(desc, label); - if (ret) - return ERR_PTR(ret); + if (ret) { + if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE)) + return ERR_PTR(ret); + + /* + * This happens when there are several consumers for + * the same GPIO line: we just return here without + * further initialization. It is a bit of a hack. + * This is necessary to support fixed regulators. + * + * FIXME: Make this more sane and safe. + */ + dev_info(consumer, + "nonexclusive access to GPIO for %s\n", con_id); + return desc; + } - ret = gpiod_configure_flags(desc, propname, lflags, dflags); + ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); if (ret < 0) { + dev_dbg(consumer, "setup of GPIO %s failed\n", con_id); gpiod_put(desc); return ERR_PTR(ret); } @@ -3937,29 +3963,12 @@ static struct gpio_desc *fwnode_get_named_gpiod(struct fwnode_handle *fwnode, * In case of error an ERR_PTR() is returned. */ struct gpio_desc *fwnode_gpiod_get_index(struct fwnode_handle *fwnode, - const char *con_id, int index, + const char *con_id, + int index, enum gpiod_flags flags, const char *label) { - struct gpio_desc *desc; - char prop_name[32]; /* 32 is max size of property name */ - unsigned int i; - - for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { - if (con_id) - snprintf(prop_name, sizeof(prop_name), "%s-%s", - con_id, gpio_suffixes[i]); - else - snprintf(prop_name, sizeof(prop_name), "%s", - gpio_suffixes[i]); - - desc = fwnode_get_named_gpiod(fwnode, prop_name, index, flags, - label); - if (!gpiod_not_found(desc)) - break; - } - - return desc; + return gpiod_find_and_request(NULL, fwnode, con_id, index, flags, label, false); } EXPORT_SYMBOL_GPL(fwnode_gpiod_get_index); @@ -4113,72 +4122,11 @@ struct gpio_desc *__must_check gpiod_get_index(struct device *dev, unsigned int idx, enum gpiod_flags flags) { - unsigned long lookupflags = GPIO_LOOKUP_FLAGS_DEFAULT; - struct gpio_desc *desc = NULL; - int ret; - /* Maybe we have a device name, maybe not */ - const char *devname = dev ? dev_name(dev) : "?"; struct fwnode_handle *fwnode = dev ? dev_fwnode(dev) : NULL; + const char *devname = dev ? dev_name(dev) : "?"; + const char *label = con_id ?: devname; - dev_dbg(dev, "GPIO lookup for consumer %s\n", con_id); - - /* Using device tree? */ - if (is_of_node(fwnode)) { - dev_dbg(dev, "using device tree for GPIO lookup\n"); - desc = of_find_gpio(to_of_node(fwnode), - con_id, idx, &lookupflags); - } else if (is_acpi_node(fwnode)) { - dev_dbg(dev, "using ACPI for GPIO lookup\n"); - desc = acpi_find_gpio(fwnode, - con_id, idx, &flags, &lookupflags); - } - - /* - * Either we are not using DT or ACPI, or their lookup did not return - * a result. In that case, use platform lookup as a fallback. - */ - if (!desc || gpiod_not_found(desc)) { - dev_dbg(dev, "using lookup tables for GPIO lookup\n"); - desc = gpiod_find(dev, con_id, idx, &lookupflags); - } - - if (IS_ERR(desc)) { - dev_dbg(dev, "No GPIO consumer %s found\n", con_id); - return desc; - } - - /* - * If a connection label was passed use that, else attempt to use - * the device name as label - */ - ret = gpiod_request(desc, con_id ?: devname); - if (ret) { - if (!(ret == -EBUSY && flags & GPIOD_FLAGS_BIT_NONEXCLUSIVE)) - return ERR_PTR(ret); - - /* - * This happens when there are several consumers for - * the same GPIO line: we just return here without - * further initialization. It is a bit of a hack. - * This is necessary to support fixed regulators. - * - * FIXME: Make this more sane and safe. - */ - dev_info(dev, "nonexclusive access to GPIO for %s\n", con_id ?: devname); - return desc; - } - - ret = gpiod_configure_flags(desc, con_id, lookupflags, flags); - if (ret < 0) { - dev_dbg(dev, "setup of GPIO %s failed\n", con_id); - gpiod_put(desc); - return ERR_PTR(ret); - } - - blocking_notifier_call_chain(&desc->gdev->notifier, - GPIOLINE_CHANGED_REQUESTED, desc); - - return desc; + return gpiod_find_and_request(dev, fwnode, con_id, idx, flags, label, true); } EXPORT_SYMBOL_GPL(gpiod_get_index); -- 2.7.4