diff options
Diffstat (limited to 'drivers/gpio/gpiolib-of.c')
| -rw-r--r-- | drivers/gpio/gpiolib-of.c | 168 |
1 files changed, 103 insertions, 65 deletions
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index e7770eedd146..2e537ee979f3 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -46,16 +46,19 @@ enum of_gpio_flags { * @propname: property name containing gpio specifier(s) * * The function returns the count of GPIOs specified for a node. - * Note that the empty GPIO specifiers count too. Returns either - * Number of gpios defined in property, - * -EINVAL for an incorrectly formed gpios property, or - * -ENOENT for a missing gpios property + * NOTE: The empty GPIO specifiers count too. * - * Example: - * gpios = <0 - * &gpio1 1 2 - * 0 - * &gpio2 3 4>; + * Returns: + * Either number of GPIOs defined in the property, or + * * %-EINVAL for an incorrectly formed "gpios" property, or + * * %-ENOENT for a missing "gpios" property. + * + * Example:: + * + * gpios = <0 + * &gpio1 1 2 + * 0 + * &gpio2 3 4>; * * The above example defines four GPIOs, two of which are not specified. * This function will return '4' @@ -68,7 +71,7 @@ static int of_gpio_named_count(const struct device_node *np, /** * of_gpio_spi_cs_get_count() - special GPIO counting for SPI - * @dev: Consuming device + * @np: Consuming device node * @con_id: Function within the GPIO consumer * * Some elder GPIO controllers need special quirks. Currently we handle @@ -77,11 +80,15 @@ static int of_gpio_named_count(const struct device_node *np, * "gpios" for the chip select lines. If we detect this, we redirect * the counting of "cs-gpios" to count "gpios" transparent to the * driver. + * + * Returns: + * Either number of GPIOs defined in the property, or + * * %-EINVAL for an incorrectly formed "gpios" property, or + * * %-ENOENT for a missing "gpios" property. */ -static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id) +static int of_gpio_spi_cs_get_count(const struct device_node *np, + const char *con_id) { - struct device_node *np = dev->of_node; - if (!IS_ENABLED(CONFIG_SPI_MASTER)) return 0; if (!con_id || strcmp(con_id, "cs")) @@ -93,34 +100,28 @@ static int of_gpio_spi_cs_get_count(struct device *dev, const char *con_id) return of_gpio_named_count(np, "gpios"); } -int of_gpio_get_count(struct device *dev, const char *con_id) +int of_gpio_count(const struct fwnode_handle *fwnode, const char *con_id) { + const struct device_node *np = to_of_node(fwnode); int ret; char propname[32]; - unsigned int i; - ret = of_gpio_spi_cs_get_count(dev, con_id); + ret = of_gpio_spi_cs_get_count(np, con_id); if (ret > 0) return ret; - for (i = 0; i < ARRAY_SIZE(gpio_suffixes); i++) { - if (con_id) - snprintf(propname, sizeof(propname), "%s-%s", - con_id, gpio_suffixes[i]); - else - snprintf(propname, sizeof(propname), "%s", - gpio_suffixes[i]); - - ret = of_gpio_named_count(dev->of_node, propname); + for_each_gpio_property_name(propname, con_id) { + ret = of_gpio_named_count(np, propname); if (ret > 0) break; } return ret ? ret : -ENOENT; } -static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data) +static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, + const void *data) { - struct of_phandle_args *gpiospec = data; + const struct of_phandle_args *gpiospec = data; return device_match_of_node(&chip->gpiodev->dev, gpiospec->np) && chip->of_xlate && @@ -128,7 +129,7 @@ static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data) } static struct gpio_device * -of_find_gpio_device_by_xlate(struct of_phandle_args *gpiospec) +of_find_gpio_device_by_xlate(const struct of_phandle_args *gpiospec) { return gpio_device_find(gpiospec, of_gpiochip_match_node_and_xlate); } @@ -202,6 +203,24 @@ static void of_gpio_try_fixup_polarity(const struct device_node *np, */ { "qi,lb60", "rb-gpios", true }, #endif +#if IS_ENABLED(CONFIG_PCI_LANTIQ) + /* + * According to the PCI specification, the RST# pin is an + * active-low signal. However, most of the device trees that + * have been widely used for a long time incorrectly describe + * reset GPIO as active-high, and were also using wrong name + * for the property. + */ + { "lantiq,pci-xway", "gpio-reset", false }, +#endif +#if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2005) + /* + * DTS for Nokia N900 incorrectly specified "active high" + * polarity for the reset line, while the chip actually + * treats it as "active low". + */ + { "ti,tsc2005", "reset-gpios", false }, +#endif }; unsigned int i; @@ -318,12 +337,11 @@ static void of_gpio_flags_quirks(const struct device_node *np, * to determine if the flags should have inverted semantics. */ if (IS_ENABLED(CONFIG_SPI_MASTER) && !strcmp(propname, "cs-gpios") && - of_property_read_bool(np, "cs-gpios")) { - struct device_node *child; + of_property_present(np, "cs-gpios")) { u32 cs; int ret; - for_each_child_of_node(np, child) { + for_each_child_of_node_scoped(np, child) { ret = of_property_read_u32(child, "reg", &cs); if (ret) continue; @@ -344,7 +362,6 @@ static void of_gpio_flags_quirks(const struct device_node *np, "spi-cs-high"); of_gpio_quirk_polarity(child, active_high, flags); - of_node_put(child); break; } } @@ -364,7 +381,8 @@ static void of_gpio_flags_quirks(const struct device_node *np, * @index: index of the GPIO * @flags: a flags pointer to fill in * - * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno + * Returns: + * GPIO descriptor to use with Linux GPIO API, or one of the errno * value on the error condition. If @flags is not NULL the function also fills * in flags for the GPIO. */ @@ -414,7 +432,10 @@ out: * @propname: Name of property containing gpio specifier(s) * @index: index of the GPIO * - * Returns GPIO number to use with Linux generic GPIO API, or one of the errno + * **DEPRECATED** This function is deprecated and must not be used in new code. + * + * Returns: + * GPIO number to use with Linux generic GPIO API, or one of the errno * value on the error condition. */ int of_get_named_gpio(const struct device_node *np, const char *propname, @@ -501,9 +522,9 @@ static struct gpio_desc *of_find_gpio_rename(struct device_node *np, { "reset", "reset-n-io", "marvell,nfc-uart" }, { "reset", "reset-n-io", "mrvl,nfc-uart" }, #endif -#if !IS_ENABLED(CONFIG_PCI_LANTIQ) +#if IS_ENABLED(CONFIG_PCI_LANTIQ) /* MIPS Lantiq PCI */ - { "reset", "gpios-reset", "lantiq,pci-xway" }, + { "reset", "gpio-reset", "lantiq,pci-xway" }, #endif /* @@ -666,23 +687,14 @@ static const of_find_gpio_quirk of_find_gpio_quirks[] = { struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, unsigned int idx, unsigned long *flags) { - char prop_name[32]; /* 32 is max size of property name */ + char propname[32]; /* 32 is max size of property name */ enum of_gpio_flags of_flags; const of_find_gpio_quirk *q; struct gpio_desc *desc; - unsigned int i; /* Try GPIO property "foo-gpios" and "foo-gpio" */ - 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 = of_get_named_gpiod_flags(np, prop_name, idx, &of_flags); - + for_each_gpio_property_name(propname, con_id) { + desc = of_get_named_gpiod_flags(np, propname, idx, &of_flags); if (!gpiod_not_found(desc)) break; } @@ -709,7 +721,8 @@ struct gpio_desc *of_find_gpio(struct device_node *np, const char *con_id, * of_find_gpio() or of_parse_own_gpio() * @dflags: gpiod_flags - optional GPIO initialization flags * - * Returns GPIO descriptor to use with Linux GPIO API, or one of the errno + * Returns: + * GPIO descriptor to use with Linux GPIO API, or one of the errno * value on the error condition. */ static struct gpio_desc *of_parse_own_gpio(struct device_node *np, @@ -777,7 +790,8 @@ static struct gpio_desc *of_parse_own_gpio(struct device_node *np, * @chip: gpio chip to act on * @hog: device node describing the hogs * - * Returns error if it fails otherwise 0 on success. + * Returns: + * 0 on success, or negative errno on failure. */ static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) { @@ -798,7 +812,7 @@ static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) return ret; #ifdef CONFIG_OF_DYNAMIC - desc->hog = hog; + WRITE_ONCE(desc->hog, hog); #endif } @@ -811,22 +825,21 @@ static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog) * * This is only used by of_gpiochip_add to request/set GPIO initial * configuration. - * It returns error if it fails otherwise 0 on success. + * + * Returns: + * 0 on success, or negative errno on failure. */ static int of_gpiochip_scan_gpios(struct gpio_chip *chip) { - struct device_node *np; int ret; - for_each_available_child_of_node(dev_of_node(&chip->gpiodev->dev), np) { + for_each_available_child_of_node_scoped(dev_of_node(&chip->gpiodev->dev), np) { if (!of_property_read_bool(np, "gpio-hog")) continue; ret = of_gpiochip_add_hog(chip, np); - if (ret < 0) { - of_node_put(np); + if (ret < 0) return ret; - } of_node_set_flag(np, OF_POPULATED); } @@ -846,11 +859,11 @@ static void of_gpiochip_remove_hog(struct gpio_chip *chip, struct gpio_desc *desc; for_each_gpio_desc_with_flag(chip, desc, FLAG_IS_HOGGED) - if (desc->hog == hog) + if (READ_ONCE(desc->hog) == hog) gpiochip_free_own_desc(desc); } -static int of_gpiochip_match_node(struct gpio_chip *chip, void *data) +static int of_gpiochip_match_node(struct gpio_chip *chip, const void *data) { return device_match_of_node(&chip->gpiodev->dev, data); } @@ -924,6 +937,9 @@ struct notifier_block gpio_of_notifier = { * This is simple translation function, suitable for the most 1:1 mapped * GPIO chips. This function performs only one sanity check: whether GPIO * is less than ngpios (that is specified in the gpio_chip). + * + * Returns: + * GPIO number (>= 0) on success, negative errno on failure. */ static int of_gpio_simple_xlate(struct gpio_chip *gc, const struct of_phandle_args *gpiospec, @@ -973,6 +989,9 @@ static int of_gpio_simple_xlate(struct gpio_chip *gc, * If succeeded, this function will map bank's memory and will * do all necessary work for you. Then you'll able to use .regs * to manage GPIOs from the callbacks. + * + * Returns: + * 0 on success, or negative errno on failure. */ int of_mm_gpiochip_add_data(struct device_node *np, struct of_mm_gpio_chip *mm_gc, @@ -1034,16 +1053,16 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) struct of_phandle_args pinspec; struct pinctrl_dev *pctldev; struct device_node *np; - int index = 0, ret; + int index = 0, ret, trim; const char *name; static const char group_names_propname[] = "gpio-ranges-group-names"; - struct property *group_names; + bool has_group_names; np = dev_of_node(&chip->gpiodev->dev); if (!np) return 0; - group_names = of_find_property(np, group_names_propname, NULL); + has_group_names = of_property_present(np, group_names_propname); for (;; index++) { ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, @@ -1056,8 +1075,15 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) if (!pctldev) return -EPROBE_DEFER; + /* Ignore ranges outside of this GPIO chip */ + if (pinspec.args[0] >= (chip->offset + chip->ngpio)) + continue; + if (pinspec.args[0] + pinspec.args[2] <= chip->offset) + continue; + if (pinspec.args[2]) { - if (group_names) { + /* npins != 0: linear range */ + if (has_group_names) { of_property_read_string_index(np, group_names_propname, index, &name); @@ -1067,7 +1093,19 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) break; } } - /* npins != 0: linear range */ + + /* Trim the range to fit this GPIO chip */ + if (chip->offset > pinspec.args[0]) { + trim = chip->offset - pinspec.args[0]; + pinspec.args[2] -= trim; + pinspec.args[1] += trim; + pinspec.args[0] = 0; + } else { + pinspec.args[0] -= chip->offset; + } + if ((pinspec.args[0] + pinspec.args[2]) > chip->ngpio) + pinspec.args[2] = chip->ngpio - pinspec.args[0]; + ret = gpiochip_add_pin_range(chip, pinctrl_dev_get_devname(pctldev), pinspec.args[0], @@ -1083,7 +1121,7 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) break; } - if (!group_names) { + if (!has_group_names) { pr_err("%pOF: GPIO group range requested but no %s property.\n", np, group_names_propname); break; |