diff options
Diffstat (limited to 'drivers/gpio/gpiolib-of.c')
| -rw-r--r-- | drivers/gpio/gpiolib-of.c | 283 |
1 files changed, 213 insertions, 70 deletions
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index cb0cefaec37e..37ab78243fab 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' @@ -77,6 +80,11 @@ 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(const struct device_node *np, const char *con_id) @@ -97,20 +105,12 @@ 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(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]); - + for_each_gpio_property_name(propname, con_id) { ret = of_gpio_named_count(np, propname); if (ret > 0) break; @@ -193,6 +193,8 @@ static void of_gpio_try_fixup_polarity(const struct device_node *np, */ { "himax,hx8357", "gpios-reset", false }, { "himax,hx8369", "gpios-reset", false }, +#endif +#if IS_ENABLED(CONFIG_MTD_NAND_JZ4780) /* * The rb-gpios semantics was undocumented and qi,lb60 (along with * the ingenic driver) got it wrong. The active state encodes the @@ -203,6 +205,42 @@ static void of_gpio_try_fixup_polarity(const struct device_node *np, */ { "qi,lb60", "rb-gpios", true }, #endif +#if IS_ENABLED(CONFIG_IEEE802154_CA8210) + /* + * According to the datasheet, the NRST pin 27 is an active-low + * signal. However, the device tree schema and admittedly + * the out-of-tree implementations have been used for a long + * time incorrectly by describing reset GPIO as active-high. + */ + { "cascoda,ca8210", "reset-gpio", false }, +#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_REGULATOR_S5M8767) + /* + * According to S5M8767, the DVS and DS pin are + * active-high signals. However, exynos5250-spring.dts use + * active-low setting. + */ + { "samsung,s5m8767-pmic", "s5m8767,pmic-buck-dvs-gpios", true }, + { "samsung,s5m8767-pmic", "s5m8767,pmic-buck-ds-gpios", true }, +#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; @@ -239,6 +277,9 @@ static void of_gpio_set_polarity_by_property(const struct device_node *np, { "fsl,imx8qm-fec", "phy-reset-gpios", "phy-reset-active-high" }, { "fsl,s32v234-fec", "phy-reset-gpios", "phy-reset-active-high" }, #endif +#if IS_ENABLED(CONFIG_MMC_ATMELMCI) + { "atmel,hsmci", "cd-gpios", "cd-inverted" }, +#endif #if IS_ENABLED(CONFIG_PCI_IMX6) { "fsl,imx6q-pcie", "reset-gpio", "reset-gpio-active-high" }, { "fsl,imx6sx-pcie", "reset-gpio", "reset-gpio-active-high" }, @@ -265,9 +306,6 @@ static void of_gpio_set_polarity_by_property(const struct device_node *np, { "regulator-gpio", "enable-gpio", "enable-active-high" }, { "regulator-gpio", "enable-gpios", "enable-active-high" }, #endif -#if IS_ENABLED(CONFIG_MMC_ATMELMCI) - { "atmel,hsmci", "cd-gpios", "cd-inverted" }, -#endif }; unsigned int i; bool active_high; @@ -319,12 +357,11 @@ 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; @@ -345,7 +382,6 @@ 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; } } @@ -365,7 +401,8 @@ 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. */ @@ -417,7 +454,8 @@ out: * * **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 + * 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, @@ -504,9 +542,9 @@ 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 /* @@ -669,23 +707,14 @@ 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 */ - enum of_gpio_flags of_flags; + char propname[32]; /* 32 is max size of property name */ + enum of_gpio_flags of_flags = 0; 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; } @@ -712,7 +741,8 @@ 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, @@ -780,7 +810,8 @@ 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) { @@ -814,22 +845,21 @@ 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); } @@ -919,7 +949,7 @@ struct notifier_block gpio_of_notifier = { #endif /* CONFIG_OF_DYNAMIC */ /** - * of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags + * of_gpio_twocell_xlate - translate twocell gpiospec to the GPIO number and flags * @gc: pointer to the gpio_chip structure * @gpiospec: GPIO specifier as found in the device tree * @flags: a flags pointer to fill in @@ -927,10 +957,13 @@ 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, - u32 *flags) +static int of_gpio_twocell_xlate(struct gpio_chip *gc, + const struct of_phandle_args *gpiospec, + u32 *flags) { /* * We're discouraging gpio_cells < 2, since that way you'll have to @@ -938,7 +971,7 @@ static int of_gpio_simple_xlate(struct gpio_chip *gc, * number and the flags from a single gpio cell -- this is possible, * but not recommended). */ - if (gc->of_gpio_n_cells < 2) { + if (gc->of_gpio_n_cells != 2) { WARN_ON(1); return -EINVAL; } @@ -955,6 +988,49 @@ static int of_gpio_simple_xlate(struct gpio_chip *gc, return gpiospec->args[0]; } +/** + * of_gpio_threecell_xlate - translate threecell gpiospec to the GPIO number and flags + * @gc: pointer to the gpio_chip structure + * @gpiospec: GPIO specifier as found in the device tree + * @flags: a flags pointer to fill in + * + * This is simple translation function, suitable for the most 1:n mapped + * GPIO chips, i.e. several GPIO chip instances from one device tree node. + * In this case the following binding is implied: + * + * foo-gpios = <&gpio instance offset flags>; + * + * Returns: + * GPIO number (>= 0) on success, negative errno on failure. + */ +static int of_gpio_threecell_xlate(struct gpio_chip *gc, + const struct of_phandle_args *gpiospec, + u32 *flags) +{ + if (gc->of_gpio_n_cells != 3) { + WARN_ON(1); + return -EINVAL; + } + + if (WARN_ON(gpiospec->args_count != 3)) + return -EINVAL; + + /* + * Check chip instance number, the driver responds with true if + * this is the chip we are looking for. + */ + if (!gc->of_node_instance_match(gc, gpiospec->args[0])) + return -EINVAL; + + if (gpiospec->args[1] >= gc->ngpio) + return -EINVAL; + + if (flags) + *flags = gpiospec->args[2]; + + return gpiospec->args[1]; +} + #if IS_ENABLED(CONFIG_OF_GPIO_MM_GPIOCHIP) #include <linux/gpio/legacy-of-mm-gpiochip.h> /** @@ -976,6 +1052,9 @@ 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, @@ -1037,19 +1116,30 @@ 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; + int offset; /* Offset of the first GPIO line on the chip */ + int pin; /* Pin base number in the range */ + int count; /* Number of pins/GPIO lines to map */ 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, + /* + * Ordinary phandles contain 2-3 cells: + * gpios = <&gpio [instance] offset flags>; + * Ranges always contain one more cell: + * gpio-ranges <&pinctrl [gpio_instance] gpio_offet pin_offet count>; + * This is why we parse chip->of_gpio_n_cells + 1 cells + */ + ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", + chip->of_gpio_n_cells + 1, index, &pinspec); if (ret) break; @@ -1059,8 +1149,35 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) if (!pctldev) return -EPROBE_DEFER; - if (pinspec.args[2]) { - if (group_names) { + if (chip->of_gpio_n_cells == 3) { + /* First cell is the gpiochip instance number */ + offset = pinspec.args[1]; + pin = pinspec.args[2]; + count = pinspec.args[3]; + } else { + offset = pinspec.args[0]; + pin = pinspec.args[1]; + count = pinspec.args[2]; + } + + /* + * With multiple GPIO chips per node, check that this chip is the + * right instance. + */ + if (chip->of_node_instance_match && + (chip->of_gpio_n_cells == 3) && + !chip->of_node_instance_match(chip, pinspec.args[0])) + continue; + + /* Ignore ranges outside of this GPIO chip */ + if (offset >= (chip->offset + chip->ngpio)) + continue; + if (offset + count <= chip->offset) + continue; + + if (count) { + /* npins != 0: linear range */ + if (has_group_names) { of_property_read_string_index(np, group_names_propname, index, &name); @@ -1070,23 +1187,35 @@ 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 > offset) { + trim = chip->offset - offset; + count -= trim; + pin += trim; + offset = 0; + } else { + offset -= chip->offset; + } + if ((offset + count) > chip->ngpio) + count = chip->ngpio - offset; + ret = gpiochip_add_pin_range(chip, pinctrl_dev_get_devname(pctldev), - pinspec.args[0], - pinspec.args[1], - pinspec.args[2]); + offset, + pin, + count); if (ret) return ret; } else { /* npins == 0: special range */ - if (pinspec.args[1]) { + if (pin) { pr_err("%pOF: Illegal gpio-range format.\n", np); 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; @@ -1105,7 +1234,7 @@ static int of_gpiochip_add_pin_range(struct gpio_chip *chip) } ret = gpiochip_add_pingroup_range(chip, pctldev, - pinspec.args[0], name); + offset, name); if (ret) return ret; } @@ -1128,8 +1257,14 @@ int of_gpiochip_add(struct gpio_chip *chip) return 0; if (!chip->of_xlate) { - chip->of_gpio_n_cells = 2; - chip->of_xlate = of_gpio_simple_xlate; + if (chip->of_gpio_n_cells == 3) { + if (!chip->of_node_instance_match) + return -EINVAL; + chip->of_xlate = of_gpio_threecell_xlate; + } else { + chip->of_gpio_n_cells = 2; + chip->of_xlate = of_gpio_twocell_xlate; + } } if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS) @@ -1152,3 +1287,11 @@ void of_gpiochip_remove(struct gpio_chip *chip) { of_node_put(dev_of_node(&chip->gpiodev->dev)); } + +bool of_gpiochip_instance_match(struct gpio_chip *gc, unsigned int index) +{ + if (gc->of_node_instance_match) + return gc->of_node_instance_match(gc, index); + + return false; +} |