From f9f890ba2b13ea9ccfffd0e7354c7b64d9109790 Mon Sep 17 00:00:00 2001 From: Serge Semin Date: Thu, 30 Jul 2020 18:28:01 +0300 Subject: gpio: dwapb: Add max GPIOs macro Add a new macro DWAPB_MAX_GPIOS which defines the maximum possible number of GPIO lines corresponding to the maximum DW APB GPIO controller port width. Use the new macro instead of number literal 32 where it's applicable. Suggested-by: Andy Shevchenko Signed-off-by: Serge Semin Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20200730152808.2955-5-Sergey.Semin@baikalelectronics.ru Signed-off-by: Linus Walleij --- include/linux/platform_data/gpio-dwapb.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/linux/platform_data/gpio-dwapb.h b/include/linux/platform_data/gpio-dwapb.h index ff1be737bad6..0aa5c6720259 100644 --- a/include/linux/platform_data/gpio-dwapb.h +++ b/include/linux/platform_data/gpio-dwapb.h @@ -6,12 +6,14 @@ #ifndef GPIO_DW_APB_H #define GPIO_DW_APB_H +#define DWAPB_MAX_GPIOS 32 + struct dwapb_port_property { struct fwnode_handle *fwnode; unsigned int idx; unsigned int ngpio; unsigned int gpio_base; - int irq[32]; + int irq[DWAPB_MAX_GPIOS]; bool irq_shared; }; -- cgit v1.2.3 From d284c16f84c9f8facdde25c9c077cfdcb66163d5 Mon Sep 17 00:00:00 2001 From: dillon min Date: Thu, 3 Sep 2020 15:30:22 +0800 Subject: gpio: tc35894: Disable Direct KBD interrupts to enable gpio irq On tc35894, have to disable direct keypad interrupts to make it as general purpose interrupts functionality work. if not, after chip reset, IRQST(0x91) will always 0x20, IRQN always low level, can't be clear. Configure DIRECTx to enable general purpose gpio mode, else read GPIOMISx register always zero in irq routine. verified on tc35894, need more test on other tc3589x. Signed-off-by: dillon min Acked-by: Lee Jones Signed-off-by: Bartosz Golaszewski --- drivers/gpio/gpio-tc3589x.c | 18 ++++++++++++++++-- include/linux/mfd/tc3589x.h | 6 ++++++ 2 files changed, 22 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/drivers/gpio/gpio-tc3589x.c b/drivers/gpio/gpio-tc3589x.c index 58b0da9eb76f..79d285b845dc 100644 --- a/drivers/gpio/gpio-tc3589x.c +++ b/drivers/gpio/gpio-tc3589x.c @@ -19,9 +19,9 @@ * These registers are modified under the irq bus lock and cached to avoid * unnecessary writes in bus_sync_unlock. */ -enum { REG_IBE, REG_IEV, REG_IS, REG_IE }; +enum { REG_IBE, REG_IEV, REG_IS, REG_IE, REG_DIRECT }; -#define CACHE_NR_REGS 4 +#define CACHE_NR_REGS 5 #define CACHE_NR_BANKS 3 struct tc3589x_gpio { @@ -200,6 +200,7 @@ static void tc3589x_gpio_irq_sync_unlock(struct irq_data *d) [REG_IEV] = TC3589x_GPIOIEV0, [REG_IS] = TC3589x_GPIOIS0, [REG_IE] = TC3589x_GPIOIE0, + [REG_DIRECT] = TC3589x_DIRECT0, }; int i, j; @@ -228,6 +229,7 @@ static void tc3589x_gpio_irq_mask(struct irq_data *d) int mask = BIT(offset % 8); tc3589x_gpio->regs[REG_IE][regoffset] &= ~mask; + tc3589x_gpio->regs[REG_DIRECT][regoffset] |= mask; } static void tc3589x_gpio_irq_unmask(struct irq_data *d) @@ -239,6 +241,7 @@ static void tc3589x_gpio_irq_unmask(struct irq_data *d) int mask = BIT(offset % 8); tc3589x_gpio->regs[REG_IE][regoffset] |= mask; + tc3589x_gpio->regs[REG_DIRECT][regoffset] &= ~mask; } static struct irq_chip tc3589x_gpio_irq_chip = { @@ -334,6 +337,17 @@ static int tc3589x_gpio_probe(struct platform_device *pdev) if (ret < 0) return ret; + /* For tc35894, have to disable Direct KBD interrupts, + * else IRQST will always be 0x20, IRQN low level, can't + * clear the irq status. + * TODO: need more test on other tc3589x chip. + * + */ + ret = tc3589x_reg_write(tc3589x, TC3589x_DKBDMSK, + TC3589x_DKBDMSK_ELINT | TC3589x_DKBDMSK_EINT); + if (ret < 0) + return ret; + ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, tc3589x_gpio_irq, IRQF_ONESHOT, "tc3589x-gpio", diff --git a/include/linux/mfd/tc3589x.h b/include/linux/mfd/tc3589x.h index bb2b19599761..b84955410e03 100644 --- a/include/linux/mfd/tc3589x.h +++ b/include/linux/mfd/tc3589x.h @@ -19,6 +19,9 @@ enum tx3589x_block { #define TC3589x_RSTCTRL_KBDRST (1 << 1) #define TC3589x_RSTCTRL_GPIRST (1 << 0) +#define TC3589x_DKBDMSK_ELINT (1 << 1) +#define TC3589x_DKBDMSK_EINT (1 << 0) + /* Keyboard Configuration Registers */ #define TC3589x_KBDSETTLE_REG 0x01 #define TC3589x_KBDBOUNCE 0x02 @@ -101,6 +104,9 @@ enum tx3589x_block { #define TC3589x_GPIOODM2 0xE4 #define TC3589x_GPIOODE2 0xE5 +#define TC3589x_DIRECT0 0xEC +#define TC3589x_DKBDMSK 0xF3 + #define TC3589x_INT_GPIIRQ 0 #define TC3589x_INT_TI0IRQ 1 #define TC3589x_INT_TI1IRQ 2 -- cgit v1.2.3 From 6b6ff4acb310a0351005474673f1e09a90020efd Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Wed, 9 Sep 2020 10:54:24 +0200 Subject: device: property: add helpers to count items in string arrays Instead of doing the following: count = device_property_read_string_array(dev, propname, NULL, 0); Let's provide inline helpers with hardcoded arguments for counting strings in property arrays. Suggested-by: Andy Shevchenko Signed-off-by: Bartosz Golaszewski Reviewed-by: Mika Westerberg Reviewed-by: Andy Shevchenko --- include/linux/property.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) (limited to 'include') diff --git a/include/linux/property.h b/include/linux/property.h index 9f805c442819..75c178055bc9 100644 --- a/include/linux/property.h +++ b/include/linux/property.h @@ -170,6 +170,12 @@ static inline int device_property_count_u64(struct device *dev, const char *prop return device_property_read_u64_array(dev, propname, NULL, 0); } +static inline int device_property_string_array_count(struct device *dev, + const char *propname) +{ + return device_property_read_string_array(dev, propname, NULL, 0); +} + static inline bool fwnode_property_read_bool(const struct fwnode_handle *fwnode, const char *propname) { @@ -224,6 +230,13 @@ static inline int fwnode_property_count_u64(const struct fwnode_handle *fwnode, return fwnode_property_read_u64_array(fwnode, propname, NULL, 0); } +static inline int +fwnode_property_string_array_count(const struct fwnode_handle *fwnode, + const char *propname) +{ + return fwnode_property_read_string_array(fwnode, propname, NULL, 0); +} + struct software_node; /** -- cgit v1.2.3 From 7cba1a4d5e1628e099728d849918de50dab2e24e Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Wed, 9 Sep 2020 10:54:25 +0200 Subject: gpiolib: generalize devprop_gpiochip_set_names() for device properties devprop_gpiochip_set_names() is overly complicated with taking the fwnode argument (which requires using dev_fwnode() & of_fwnode_handle() in ACPI and OF GPIO code respectively). Let's just switch to using the generic device properties. This allows us to pull the code setting line names directly into gpiochip_add_data_with_key() instead of handling it separately for ACPI and OF. Signed-off-by: Bartosz Golaszewski Reviewed-by: Andy Shevchenko Reviewed-by: Mika Westerberg --- drivers/gpio/gpiolib-acpi.c | 3 --- drivers/gpio/gpiolib-devprop.c | 20 ++++++++++---------- drivers/gpio/gpiolib-of.c | 5 ----- drivers/gpio/gpiolib.c | 8 ++++---- include/linux/gpio/driver.h | 3 +-- 5 files changed, 15 insertions(+), 24 deletions(-) (limited to 'include') diff --git a/drivers/gpio/gpiolib-acpi.c b/drivers/gpio/gpiolib-acpi.c index 9276051663da..e8dc58f771d8 100644 --- a/drivers/gpio/gpiolib-acpi.c +++ b/drivers/gpio/gpiolib-acpi.c @@ -1221,9 +1221,6 @@ void acpi_gpiochip_add(struct gpio_chip *chip) return; } - if (!chip->names) - devprop_gpiochip_set_names(chip, dev_fwnode(chip->parent)); - acpi_gpiochip_request_regions(acpi_gpio); acpi_gpiochip_scan_gpios(acpi_gpio); acpi_walk_dep_device_list(handle); diff --git a/drivers/gpio/gpiolib-devprop.c b/drivers/gpio/gpiolib-devprop.c index 26741032fa9e..31599d89a85d 100644 --- a/drivers/gpio/gpiolib-devprop.c +++ b/drivers/gpio/gpiolib-devprop.c @@ -17,25 +17,23 @@ /** * devprop_gpiochip_set_names - Set GPIO line names using device properties * @chip: GPIO chip whose lines should be named, if possible - * @fwnode: Property Node containing the gpio-line-names property * * Looks for device property "gpio-line-names" and if it exists assigns * GPIO line names for the chip. The memory allocated for the assigned - * names belong to the underlying firmware node and should not be released + * names belong to the underlying software node and should not be released * by the caller. */ -void devprop_gpiochip_set_names(struct gpio_chip *chip, - const struct fwnode_handle *fwnode) +int devprop_gpiochip_set_names(struct gpio_chip *chip) { struct gpio_device *gdev = chip->gpiodev; + struct device *dev = chip->parent; const char **names; int ret, i; int count; - count = fwnode_property_read_string_array(fwnode, "gpio-line-names", - NULL, 0); + count = device_property_string_array_count(dev, "gpio-line-names"); if (count < 0) - return; + return 0; if (count > gdev->ngpio) { dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d", @@ -45,19 +43,21 @@ void devprop_gpiochip_set_names(struct gpio_chip *chip, names = kcalloc(count, sizeof(*names), GFP_KERNEL); if (!names) - return; + return -ENOMEM; - ret = fwnode_property_read_string_array(fwnode, "gpio-line-names", + ret = device_property_read_string_array(dev, "gpio-line-names", names, count); if (ret < 0) { dev_warn(&gdev->dev, "failed to read GPIO line names\n"); kfree(names); - return; + return ret; } for (i = 0; i < count; i++) gdev->descs[i].name = names[i]; kfree(names); + + return 0; } EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names); diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index bd31dd3b6a75..2f895a2b8411 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -1026,11 +1026,6 @@ int of_gpiochip_add(struct gpio_chip *chip) if (ret) return ret; - /* If the chip defines names itself, these take precedence */ - if (!chip->names) - devprop_gpiochip_set_names(chip, - of_fwnode_handle(chip->of_node)); - of_node_get(chip->of_node); ret = of_gpiochip_scan_gpios(chip); diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 03543b8f7ab4..d50e111b0d95 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -340,9 +340,6 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc) struct gpio_device *gdev = gc->gpiodev; int i; - if (!gc->names) - return 0; - /* First check all names if they are unique */ for (i = 0; i != gc->ngpio; ++i) { struct gpio_desc *gpio; @@ -621,7 +618,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data, INIT_LIST_HEAD(&gdev->pin_ranges); #endif - ret = gpiochip_set_desc_names(gc); + if (gc->names) + ret = gpiochip_set_desc_names(gc); + else + ret = devprop_gpiochip_set_names(gc); if (ret) goto err_remove_from_list; diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index d1cef5c2715c..56485a040b82 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -756,8 +756,7 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc, enum gpiod_flags dflags); void gpiochip_free_own_desc(struct gpio_desc *desc); -void devprop_gpiochip_set_names(struct gpio_chip *gc, - const struct fwnode_handle *fwnode); +int devprop_gpiochip_set_names(struct gpio_chip *gc); #ifdef CONFIG_GPIOLIB -- cgit v1.2.3 From 32fc5aa2df12c7a95dbd1c2c9ee3eb8d7f920d9e Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Wed, 9 Sep 2020 10:54:26 +0200 Subject: gpiolib: unexport devprop_gpiochip_set_names() Now that devprop_gpiochip_set_names() is only used in a single place inside drivers/gpio/gpiolib.c, there's no need anymore for it to be exported or to even live in its own source file. Pull this function into the core source file for gpiolib. Signed-off-by: Bartosz Golaszewski Reviewed-by: Mika Westerberg Reviewed-by: Andy Shevchenko --- drivers/gpio/Makefile | 1 - drivers/gpio/gpiolib-devprop.c | 63 ------------------------------------------ drivers/gpio/gpiolib.c | 47 +++++++++++++++++++++++++++++++ include/linux/gpio/driver.h | 2 -- 4 files changed, 47 insertions(+), 66 deletions(-) delete mode 100644 drivers/gpio/gpiolib-devprop.c (limited to 'include') diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile index 4f9abff4f2dc..639275eb4e4d 100644 --- a/drivers/gpio/Makefile +++ b/drivers/gpio/Makefile @@ -6,7 +6,6 @@ ccflags-$(CONFIG_DEBUG_GPIO) += -DDEBUG obj-$(CONFIG_GPIOLIB) += gpiolib.o obj-$(CONFIG_GPIOLIB) += gpiolib-devres.o obj-$(CONFIG_GPIOLIB) += gpiolib-legacy.o -obj-$(CONFIG_GPIOLIB) += gpiolib-devprop.o obj-$(CONFIG_GPIOLIB) += gpiolib-cdev.o obj-$(CONFIG_OF_GPIO) += gpiolib-of.o obj-$(CONFIG_GPIO_SYSFS) += gpiolib-sysfs.o diff --git a/drivers/gpio/gpiolib-devprop.c b/drivers/gpio/gpiolib-devprop.c deleted file mode 100644 index 31599d89a85d..000000000000 --- a/drivers/gpio/gpiolib-devprop.c +++ /dev/null @@ -1,63 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Device property helpers for GPIO chips. - * - * Copyright (C) 2016, Intel Corporation - * Author: Mika Westerberg - */ - -#include -#include -#include -#include -#include - -#include "gpiolib.h" - -/** - * devprop_gpiochip_set_names - Set GPIO line names using device properties - * @chip: GPIO chip whose lines should be named, if possible - * - * Looks for device property "gpio-line-names" and if it exists assigns - * GPIO line names for the chip. The memory allocated for the assigned - * names belong to the underlying software node and should not be released - * by the caller. - */ -int devprop_gpiochip_set_names(struct gpio_chip *chip) -{ - struct gpio_device *gdev = chip->gpiodev; - struct device *dev = chip->parent; - const char **names; - int ret, i; - int count; - - count = device_property_string_array_count(dev, "gpio-line-names"); - if (count < 0) - return 0; - - if (count > gdev->ngpio) { - dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d", - count, gdev->ngpio); - count = gdev->ngpio; - } - - names = kcalloc(count, sizeof(*names), GFP_KERNEL); - if (!names) - return -ENOMEM; - - ret = device_property_read_string_array(dev, "gpio-line-names", - names, count); - if (ret < 0) { - dev_warn(&gdev->dev, "failed to read GPIO line names\n"); - kfree(names); - return ret; - } - - for (i = 0; i < count; i++) - gdev->descs[i].name = names[i]; - - kfree(names); - - return 0; -} -EXPORT_SYMBOL_GPL(devprop_gpiochip_set_names); diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index d50e111b0d95..b7b608ef9e6b 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -358,6 +358,53 @@ static int gpiochip_set_desc_names(struct gpio_chip *gc) return 0; } +/* + * devprop_gpiochip_set_names - Set GPIO line names using device properties + * @chip: GPIO chip whose lines should be named, if possible + * + * Looks for device property "gpio-line-names" and if it exists assigns + * GPIO line names for the chip. The memory allocated for the assigned + * names belong to the underlying software node and should not be released + * by the caller. + */ +static int devprop_gpiochip_set_names(struct gpio_chip *chip) +{ + struct gpio_device *gdev = chip->gpiodev; + struct device *dev = chip->parent; + const char **names; + int ret, i; + int count; + + count = device_property_string_array_count(dev, "gpio-line-names"); + if (count < 0) + return 0; + + if (count > gdev->ngpio) { + dev_warn(&gdev->dev, "gpio-line-names is length %d but should be at most length %d", + count, gdev->ngpio); + count = gdev->ngpio; + } + + names = kcalloc(count, sizeof(*names), GFP_KERNEL); + if (!names) + return -ENOMEM; + + ret = device_property_read_string_array(dev, "gpio-line-names", + names, count); + if (ret < 0) { + dev_warn(&gdev->dev, "failed to read GPIO line names\n"); + kfree(names); + return ret; + } + + for (i = 0; i < count; i++) + gdev->descs[i].name = names[i]; + + kfree(names); + + return 0; +} + static unsigned long *gpiochip_allocate_mask(struct gpio_chip *gc) { unsigned long *p; diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h index 56485a040b82..4a7e295c3640 100644 --- a/include/linux/gpio/driver.h +++ b/include/linux/gpio/driver.h @@ -756,8 +756,6 @@ struct gpio_desc *gpiochip_request_own_desc(struct gpio_chip *gc, enum gpiod_flags dflags); void gpiochip_free_own_desc(struct gpio_desc *desc); -int devprop_gpiochip_set_names(struct gpio_chip *gc); - #ifdef CONFIG_GPIOLIB /* lock/unlock as IRQ */ -- cgit v1.2.3 From 0fd16012adc0a994a7ce980a78e22e4de6220778 Mon Sep 17 00:00:00 2001 From: Bartosz Golaszewski Date: Tue, 29 Sep 2020 12:09:55 +0200 Subject: lib: string_helpers: provide kfree_strarray() There's a common pattern of dynamically allocating an array of char pointers and then also dynamically allocating each string in this array. Provide a helper for freeing such a string array with one call. Signed-off-by: Bartosz Golaszewski Reviewed-by: Andy Shevchenko --- include/linux/string_helpers.h | 2 ++ lib/string_helpers.c | 23 +++++++++++++++++++++++ 2 files changed, 25 insertions(+) (limited to 'include') diff --git a/include/linux/string_helpers.h b/include/linux/string_helpers.h index 86f150c2a6b6..fa06dcdc481e 100644 --- a/include/linux/string_helpers.h +++ b/include/linux/string_helpers.h @@ -94,4 +94,6 @@ char *kstrdup_quotable(const char *src, gfp_t gfp); char *kstrdup_quotable_cmdline(struct task_struct *task, gfp_t gfp); char *kstrdup_quotable_file(struct file *file, gfp_t gfp); +void kfree_strarray(char **array, size_t n); + #endif diff --git a/lib/string_helpers.c b/lib/string_helpers.c index 963050c0283e..7f2d5fbaf243 100644 --- a/lib/string_helpers.c +++ b/lib/string_helpers.c @@ -649,3 +649,26 @@ char *kstrdup_quotable_file(struct file *file, gfp_t gfp) return pathname; } EXPORT_SYMBOL_GPL(kstrdup_quotable_file); + +/** + * kfree_strarray - free a number of dynamically allocated strings contained + * in an array and the array itself + * + * @array: Dynamically allocated array of strings to free. + * @n: Number of strings (starting from the beginning of the array) to free. + * + * Passing a non-NULL @array and @n == 0 as well as NULL @array are valid + * use-cases. If @array is NULL, the function does nothing. + */ +void kfree_strarray(char **array, size_t n) +{ + unsigned int i; + + if (!array) + return; + + for (i = 0; i < n; i++) + kfree(array[i]); + kfree(array); +} +EXPORT_SYMBOL_GPL(kfree_strarray); -- cgit v1.2.3 From 539430fbbcc4a8d02451c77fff1ecd1f3b5f8abf Mon Sep 17 00:00:00 2001 From: Kent Gibson Date: Mon, 28 Sep 2020 08:27:50 +0800 Subject: gpio: uapi: define GPIO_MAX_NAME_SIZE for array sizes Replace constant array sizes with a macro constant to clarify the source of array sizes, provide a place to document any constraints on the size, and to simplify array sizing in userspace if constructing structs from their composite fields. Signed-off-by: Kent Gibson Reviewed-by: Andy Shevchenko Signed-off-by: Bartosz Golaszewski --- include/uapi/linux/gpio.h | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h index 9c27cecf406f..285cc10355b2 100644 --- a/include/uapi/linux/gpio.h +++ b/include/uapi/linux/gpio.h @@ -14,6 +14,11 @@ #include #include +/* + * The maximum size of name and label arrays. + */ +#define GPIO_MAX_NAME_SIZE 32 + /** * struct gpiochip_info - Information about a certain GPIO chip * @name: the Linux kernel name of this GPIO chip @@ -22,8 +27,8 @@ * @lines: number of GPIO lines on this chip */ struct gpiochip_info { - char name[32]; - char label[32]; + char name[GPIO_MAX_NAME_SIZE]; + char label[GPIO_MAX_NAME_SIZE]; __u32 lines; }; @@ -52,8 +57,8 @@ struct gpiochip_info { struct gpioline_info { __u32 line_offset; __u32 flags; - char name[32]; - char consumer[32]; + char name[GPIO_MAX_NAME_SIZE]; + char consumer[GPIO_MAX_NAME_SIZE]; }; /* Maximum number of requested handles */ @@ -123,7 +128,7 @@ struct gpiohandle_request { __u32 lineoffsets[GPIOHANDLES_MAX]; __u32 flags; __u8 default_values[GPIOHANDLES_MAX]; - char consumer_label[32]; + char consumer_label[GPIO_MAX_NAME_SIZE]; __u32 lines; int fd; }; @@ -182,7 +187,7 @@ struct gpioevent_request { __u32 lineoffset; __u32 handleflags; __u32 eventflags; - char consumer_label[32]; + char consumer_label[GPIO_MAX_NAME_SIZE]; int fd; }; -- cgit v1.2.3 From b53911aa872db462be2e5f1dd611b25c4c2e663b Mon Sep 17 00:00:00 2001 From: Kent Gibson Date: Mon, 28 Sep 2020 08:27:51 +0800 Subject: gpio: uapi: define uAPI v2 Add a new version of the uAPI to address existing 32/64-bit alignment issues, add support for debounce and event sequence numbers, allow requested lines with different configurations, and provide some future proofing by adding padding reserved for future use. The alignment issue relates to the gpioevent_data, which packs to different sizes on 32-bit and 64-bit platforms. That creates problems for 32-bit apps running on 64-bit kernels. uAPI v2 addresses that particular issue, and the problem more generally, by adding pad fields that explicitly pad structs out to 64-bit boundaries, so they will pack to the same size now, and even if some of the reserved padding is used for __u64 fields in the future. The new structs have been analysed with pahole to ensure that they are sized as expected and contain no implicit padding. The lack of future proofing in v1 makes it impossible to, for example, add the debounce feature that is included in v2. The future proofing is addressed by providing configurable attributes in line config and reserved padding in all structs for future features. Specifically, the line request, config, info, info_changed and event structs receive updated versions and new ioctls. As the majority of the structs and ioctls were being replaced, it is opportune to rework some of the other aspects of the uAPI: v1 has three different flags fields, each with their own separate bit definitions. In v2 that is collapsed to one - gpio_v2_line_flag. The handle and event requests are merged into a single request, the line request, as the two requests were mostly the same other than the edge detection provided by event requests. As a byproduct, the v2 uAPI allows for multiple lines producing edge events on the same line handle. This is a new capability as v1 only supports a single line in an event request. As a consequence, there are now only two types of file handle to be concerned with, the chip and the line, and it is clearer which ioctls apply to which type of handle. There is also some minor renaming of fields for consistency compared to their v1 counterparts, e.g. offset rather than lineoffset or line_offset, and consumer rather than consumer_label. Additionally, v1 GPIOHANDLES_MAX becomes GPIO_V2_LINES_MAX in v2 for clarity, and the gpiohandle_data __u8 array becomes a bitmap in gpio_v2_line_values. The v2 uAPI is mostly a reorganisation and extension of v1, so userspace code, particularly libgpiod, should readily port to it. Signed-off-by: Kent Gibson Reviewed-by: Andy Shevchenko Signed-off-by: Bartosz Golaszewski --- include/uapi/linux/gpio.h | 291 ++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 284 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h index 285cc10355b2..5904f49399de 100644 --- a/include/uapi/linux/gpio.h +++ b/include/uapi/linux/gpio.h @@ -11,11 +11,14 @@ #ifndef _UAPI_GPIO_H_ #define _UAPI_GPIO_H_ +#include #include #include /* * The maximum size of name and label arrays. + * + * Must be a multiple of 8 to ensure 32/64-bit alignment of structs. */ #define GPIO_MAX_NAME_SIZE 32 @@ -32,6 +35,265 @@ struct gpiochip_info { __u32 lines; }; +/* + * Maximum number of requested lines. + * + * Must be no greater than 64, as bitmaps are restricted here to 64-bits + * for simplicity, and a multiple of 2 to ensure 32/64-bit alignment of + * structs. + */ +#define GPIO_V2_LINES_MAX 64 + +/* + * The maximum number of configuration attributes associated with a line + * request. + */ +#define GPIO_V2_LINE_NUM_ATTRS_MAX 10 + +/** + * enum gpio_v2_line_flag - &struct gpio_v2_line_attribute.flags values + * @GPIO_V2_LINE_FLAG_USED: line is not available for request + * @GPIO_V2_LINE_FLAG_ACTIVE_LOW: line active state is physical low + * @GPIO_V2_LINE_FLAG_INPUT: line is an input + * @GPIO_V2_LINE_FLAG_OUTPUT: line is an output + * @GPIO_V2_LINE_FLAG_EDGE_RISING: line detects rising (inactive to active) + * edges + * @GPIO_V2_LINE_FLAG_EDGE_FALLING: line detects falling (active to + * inactive) edges + * @GPIO_V2_LINE_FLAG_OPEN_DRAIN: line is an open drain output + * @GPIO_V2_LINE_FLAG_OPEN_SOURCE: line is an open source output + * @GPIO_V2_LINE_FLAG_BIAS_PULL_UP: line has pull-up bias enabled + * @GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN: line has pull-down bias enabled + * @GPIO_V2_LINE_FLAG_BIAS_DISABLED: line has bias disabled + */ +enum gpio_v2_line_flag { + GPIO_V2_LINE_FLAG_USED = _BITULL(0), + GPIO_V2_LINE_FLAG_ACTIVE_LOW = _BITULL(1), + GPIO_V2_LINE_FLAG_INPUT = _BITULL(2), + GPIO_V2_LINE_FLAG_OUTPUT = _BITULL(3), + GPIO_V2_LINE_FLAG_EDGE_RISING = _BITULL(4), + GPIO_V2_LINE_FLAG_EDGE_FALLING = _BITULL(5), + GPIO_V2_LINE_FLAG_OPEN_DRAIN = _BITULL(6), + GPIO_V2_LINE_FLAG_OPEN_SOURCE = _BITULL(7), + GPIO_V2_LINE_FLAG_BIAS_PULL_UP = _BITULL(8), + GPIO_V2_LINE_FLAG_BIAS_PULL_DOWN = _BITULL(9), + GPIO_V2_LINE_FLAG_BIAS_DISABLED = _BITULL(10), +}; + +/** + * struct gpio_v2_line_values - Values of GPIO lines + * @bits: a bitmap containing the value of the lines, set to 1 for active + * and 0 for inactive. + * @mask: a bitmap identifying the lines to get or set, with each bit + * number corresponding to the index into &struct + * gpio_v2_line_request.offsets. + */ +struct gpio_v2_line_values { + __aligned_u64 bits; + __aligned_u64 mask; +}; + +/** + * enum gpio_v2_line_attr_id - &struct gpio_v2_line_attribute.id values + * identifying which field of the attribute union is in use. + * @GPIO_V2_LINE_ATTR_ID_FLAGS: flags field is in use + * @GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES: values field is in use + * @GPIO_V2_LINE_ATTR_ID_DEBOUNCE: debounce_period_us is in use + */ +enum gpio_v2_line_attr_id { + GPIO_V2_LINE_ATTR_ID_FLAGS = 1, + GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES = 2, + GPIO_V2_LINE_ATTR_ID_DEBOUNCE = 3, +}; + +/** + * struct gpio_v2_line_attribute - a configurable attribute of a line + * @id: attribute identifier with value from &enum gpio_v2_line_attr_id + * @padding: reserved for future use and must be zero filled + * @flags: if id is GPIO_V2_LINE_ATTR_ID_FLAGS, the flags for the GPIO + * line, with values from enum gpio_v2_line_flag, such as + * GPIO_V2_LINE_FLAG_ACTIVE_LOW, GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed + * together. This overrides the default flags contained in the &struct + * gpio_v2_line_config for the associated line. + * @values: if id is GPIO_V2_LINE_ATTR_ID_OUTPUT_VALUES, a bitmap + * containing the values to which the lines will be set, with each bit + * number corresponding to the index into &struct + * gpio_v2_line_request.offsets. + * @debounce_period_us: if id is GPIO_V2_LINE_ATTR_ID_DEBOUNCE, the desired + * debounce period, in microseconds + */ +struct gpio_v2_line_attribute { + __u32 id; + __u32 padding; + union { + __aligned_u64 flags; + __aligned_u64 values; + __u32 debounce_period_us; + }; +}; + +/** + * struct gpio_v2_line_config_attribute - a configuration attribute + * associated with one or more of the requested lines. + * @attr: the configurable attribute + * @mask: a bitmap identifying the lines to which the attribute applies, + * with each bit number corresponding to the index into &struct + * gpio_v2_line_request.offsets. + */ +struct gpio_v2_line_config_attribute { + struct gpio_v2_line_attribute attr; + __aligned_u64 mask; +}; + +/** + * struct gpio_v2_line_config - Configuration for GPIO lines + * @flags: flags for the GPIO lines, with values from enum + * gpio_v2_line_flag, such as GPIO_V2_LINE_FLAG_ACTIVE_LOW, + * GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed together. This is the default for + * all requested lines but may be overridden for particular lines using + * attrs. + * @num_attrs: the number of attributes in attrs + * @padding: reserved for future use and must be zero filled + * @attrs: the configuration attributes associated with the requested + * lines. Any attribute should only be associated with a particular line + * once. If an attribute is associated with a line multiple times then the + * first occurrence (i.e. lowest index) has precedence. + */ +struct gpio_v2_line_config { + __aligned_u64 flags; + __u32 num_attrs; + /* Pad to fill implicit padding and reserve space for future use. */ + __u32 padding[5]; + struct gpio_v2_line_config_attribute attrs[GPIO_V2_LINE_NUM_ATTRS_MAX]; +}; + +/** + * struct gpio_v2_line_request - Information about a request for GPIO lines + * @offsets: an array of desired lines, specified by offset index for the + * associated GPIO chip + * @consumer: a desired consumer label for the selected GPIO lines such as + * "my-bitbanged-relay" + * @config: requested configuration for the lines. + * @num_lines: number of lines requested in this request, i.e. the number + * of valid fields in the GPIO_V2_LINES_MAX sized arrays, set to 1 to + * request a single line + * @event_buffer_size: a suggested minimum number of line events that the + * kernel should buffer. This is only relevant if edge detection is + * enabled in the configuration. Note that this is only a suggested value + * and the kernel may allocate a larger buffer or cap the size of the + * buffer. If this field is zero then the buffer size defaults to a minimum + * of num_lines*16. + * @padding: reserved for future use and must be zero filled + * @fd: if successful this field will contain a valid anonymous file handle + * after a GPIO_GET_LINE_IOCTL operation, zero or negative value means + * error + */ +struct gpio_v2_line_request { + __u32 offsets[GPIO_V2_LINES_MAX]; + char consumer[GPIO_MAX_NAME_SIZE]; + struct gpio_v2_line_config config; + __u32 num_lines; + __u32 event_buffer_size; + /* Pad to fill implicit padding and reserve space for future use. */ + __u32 padding[5]; + __s32 fd; +}; + +/** + * struct gpio_v2_line_info - Information about a certain GPIO line + * @name: the name of this GPIO line, such as the output pin of the line on + * the chip, a rail or a pin header name on a board, as specified by the + * GPIO chip, may be empty + * @consumer: a functional name for the consumer of this GPIO line as set + * by whatever is using it, will be empty if there is no current user but + * may also be empty if the consumer doesn't set this up + * @flags: flags for the GPIO line, such as GPIO_V2_LINE_FLAG_ACTIVE_LOW, + * GPIO_V2_LINE_FLAG_OUTPUT etc, OR:ed together + * @offset: the local offset on this GPIO chip, fill this in when + * requesting the line information from the kernel + * @num_attrs: the number of attributes in attrs + * @attrs: the configuration attributes associated with the line + * @padding: reserved for future use + */ +struct gpio_v2_line_info { + char name[GPIO_MAX_NAME_SIZE]; + char consumer[GPIO_MAX_NAME_SIZE]; + __u32 offset; + __u32 num_attrs; + __aligned_u64 flags; + struct gpio_v2_line_attribute attrs[GPIO_V2_LINE_NUM_ATTRS_MAX]; + /* Space reserved for future use. */ + __u32 padding[4]; +}; + +/** + * enum gpio_v2_line_changed_type - &struct gpio_v2_line_changed.event_type + * values + * @GPIO_V2_LINE_CHANGED_REQUESTED: line has been requested + * @GPIO_V2_LINE_CHANGED_RELEASED: line has been released + * @GPIO_V2_LINE_CHANGED_CONFIG: line has been reconfigured + */ +enum gpio_v2_line_changed_type { + GPIO_V2_LINE_CHANGED_REQUESTED = 1, + GPIO_V2_LINE_CHANGED_RELEASED = 2, + GPIO_V2_LINE_CHANGED_CONFIG = 3, +}; + +/** + * struct gpio_v2_line_info_changed - Information about a change in status + * of a GPIO line + * @info: updated line information + * @timestamp_ns: estimate of time of status change occurrence, in nanoseconds + * @event_type: the type of change with a value from enum + * gpio_v2_line_changed_type + * @padding: reserved for future use + */ +struct gpio_v2_line_info_changed { + struct gpio_v2_line_info info; + __aligned_u64 timestamp_ns; + __u32 event_type; + /* Pad struct to 64-bit boundary and reserve space for future use. */ + __u32 padding[5]; +}; + +/** + * enum gpio_v2_line_event_id - &struct gpio_v2_line_event.id values + * @GPIO_V2_LINE_EVENT_RISING_EDGE: event triggered by a rising edge + * @GPIO_V2_LINE_EVENT_FALLING_EDGE: event triggered by a falling edge + */ +enum gpio_v2_line_event_id { + GPIO_V2_LINE_EVENT_RISING_EDGE = 1, + GPIO_V2_LINE_EVENT_FALLING_EDGE = 2, +}; + +/** + * struct gpio_v2_line_event - The actual event being pushed to userspace + * @timestamp_ns: best estimate of time of event occurrence, in nanoseconds. + * The timestamp_ns is read from CLOCK_MONOTONIC and is intended to allow the + * accurate measurement of the time between events. It does not provide + * the wall-clock time. + * @id: event identifier with value from enum gpio_v2_line_event_id + * @offset: the offset of the line that triggered the event + * @seqno: the sequence number for this event in the sequence of events for + * all the lines in this line request + * @line_seqno: the sequence number for this event in the sequence of + * events on this particular line + * @padding: reserved for future use + */ +struct gpio_v2_line_event { + __aligned_u64 timestamp_ns; + __u32 id; + __u32 offset; + __u32 seqno; + __u32 line_seqno; + /* Space reserved for future use. */ + __u32 padding[6]; +}; + +/* + * ABI v1 + */ + /* Informational flags */ #define GPIOLINE_FLAG_KERNEL (1UL << 0) /* Line used by the kernel */ #define GPIOLINE_FLAG_IS_OUT (1UL << 1) @@ -149,8 +411,6 @@ struct gpiohandle_config { __u32 padding[4]; /* padding for future use */ }; -#define GPIOHANDLE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0a, struct gpiohandle_config) - /** * struct gpiohandle_data - Information of values on a GPIO handle * @values: when getting the state of lines this contains the current @@ -161,9 +421,6 @@ struct gpiohandle_data { __u8 values[GPIOHANDLES_MAX]; }; -#define GPIOHANDLE_GET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x08, struct gpiohandle_data) -#define GPIOHANDLE_SET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x09, struct gpiohandle_data) - /* Eventrequest flags */ #define GPIOEVENT_REQUEST_RISING_EDGE (1UL << 0) #define GPIOEVENT_REQUEST_FALLING_EDGE (1UL << 1) @@ -207,11 +464,31 @@ struct gpioevent_data { __u32 id; }; +/* + * v1 and v2 ioctl()s + */ #define GPIO_GET_CHIPINFO_IOCTL _IOR(0xB4, 0x01, struct gpiochip_info) +#define GPIO_GET_LINEINFO_UNWATCH_IOCTL _IOWR(0xB4, 0x0C, __u32) + +/* + * v2 ioctl()s + */ +#define GPIO_V2_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x05, struct gpio_v2_line_info) +#define GPIO_V2_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x06, struct gpio_v2_line_info) +#define GPIO_V2_GET_LINE_IOCTL _IOWR(0xB4, 0x07, struct gpio_v2_line_request) +#define GPIO_V2_LINE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0D, struct gpio_v2_line_config) +#define GPIO_V2_LINE_GET_VALUES_IOCTL _IOWR(0xB4, 0x0E, struct gpio_v2_line_values) +#define GPIO_V2_LINE_SET_VALUES_IOCTL _IOWR(0xB4, 0x0F, struct gpio_v2_line_values) + +/* + * v1 ioctl()s + */ #define GPIO_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x02, struct gpioline_info) -#define GPIO_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x0b, struct gpioline_info) -#define GPIO_GET_LINEINFO_UNWATCH_IOCTL _IOWR(0xB4, 0x0c, __u32) #define GPIO_GET_LINEHANDLE_IOCTL _IOWR(0xB4, 0x03, struct gpiohandle_request) #define GPIO_GET_LINEEVENT_IOCTL _IOWR(0xB4, 0x04, struct gpioevent_request) +#define GPIOHANDLE_GET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x08, struct gpiohandle_data) +#define GPIOHANDLE_SET_LINE_VALUES_IOCTL _IOWR(0xB4, 0x09, struct gpiohandle_data) +#define GPIOHANDLE_SET_CONFIG_IOCTL _IOWR(0xB4, 0x0A, struct gpiohandle_config) +#define GPIO_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x0B, struct gpioline_info) #endif /* _UAPI_GPIO_H_ */ -- cgit v1.2.3 From b234d233fe30c63c4e461b03e2884a6765c8e5b0 Mon Sep 17 00:00:00 2001 From: Kent Gibson Date: Mon, 28 Sep 2020 08:28:00 +0800 Subject: gpio: uapi: document uAPI v1 as deprecated Update uAPI documentation to deprecate v1 structs and ioctls. Signed-off-by: Kent Gibson Signed-off-by: Bartosz Golaszewski --- include/uapi/linux/gpio.h | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'include') diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h index 5904f49399de..07865c601099 100644 --- a/include/uapi/linux/gpio.h +++ b/include/uapi/linux/gpio.h @@ -292,6 +292,9 @@ struct gpio_v2_line_event { /* * ABI v1 + * + * This version of the ABI is deprecated. + * Use the latest version of the ABI, defined above, instead. */ /* Informational flags */ @@ -315,6 +318,9 @@ struct gpio_v2_line_event { * @consumer: a functional name for the consumer of this GPIO line as set by * whatever is using it, will be empty if there is no current user but may * also be empty if the consumer doesn't set this up + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_info instead. */ struct gpioline_info { __u32 line_offset; @@ -346,6 +352,9 @@ enum { * guarantee there are no implicit holes between it and subsequent members. * The 20-byte padding at the end makes sure we don't add any implicit padding * at the end of the structure on 64-bit architectures. + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_info_changed instead. */ struct gpioline_info_changed { struct gpioline_info info; @@ -385,6 +394,9 @@ struct gpioline_info_changed { * @fd: if successful this field will contain a valid anonymous file handle * after a GPIO_GET_LINEHANDLE_IOCTL operation, zero or negative value * means error + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_request instead. */ struct gpiohandle_request { __u32 lineoffsets[GPIOHANDLES_MAX]; @@ -404,6 +416,9 @@ struct gpiohandle_request { * this specifies the default output value, should be 0 (low) or * 1 (high), anything else than 0 or 1 will be interpreted as 1 (high) * @padding: reserved for future use and should be zero filled + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_config instead. */ struct gpiohandle_config { __u32 flags; @@ -416,6 +431,9 @@ struct gpiohandle_config { * @values: when getting the state of lines this contains the current * state of a line, when setting the state of lines these should contain * the desired target state + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_values instead. */ struct gpiohandle_data { __u8 values[GPIOHANDLES_MAX]; @@ -439,6 +457,9 @@ struct gpiohandle_data { * @fd: if successful this field will contain a valid anonymous file handle * after a GPIO_GET_LINEEVENT_IOCTL operation, zero or negative value * means error + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_request instead. */ struct gpioevent_request { __u32 lineoffset; @@ -458,6 +479,9 @@ struct gpioevent_request { * struct gpioevent_data - The actual event being pushed to userspace * @timestamp: best estimate of time of event occurrence, in nanoseconds * @id: event identifier + * + * This struct is part of ABI v1 and is deprecated. + * Use struct gpio_v2_line_event instead. */ struct gpioevent_data { __u64 timestamp; @@ -482,6 +506,8 @@ struct gpioevent_data { /* * v1 ioctl()s + * + * These ioctl()s are deprecated. Use the v2 equivalent instead. */ #define GPIO_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x02, struct gpioline_info) #define GPIO_GET_LINEHANDLE_IOCTL _IOWR(0xB4, 0x03, struct gpiohandle_request) -- cgit v1.2.3