X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=drivers%2Fgpio%2Fgpiolib-of.c;h=5fe34a9df3e6b8538ddc47a8ec6008654c89d89c;hb=814502b479ae801bbdcc53b54a7b6b6c823c04ce;hp=665f9530c950f96fd4cf54fb70c03edffbcc2ef2;hpb=91e14b294f3fe4d8b28516b21ceef187ea9b1bdf;p=firefly-linux-kernel-4.4.55.git diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 665f9530c950..5fe34a9df3e6 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -12,22 +12,26 @@ */ #include +#include #include #include #include -#include +#include #include #include #include #include #include +#include + +#include "gpiolib.h" /* Private data structure for of_gpiochip_find_and_xlate */ struct gg_data { enum of_gpio_flags *flags; struct of_phandle_args gpiospec; - int out_gpio; + struct gpio_desc *out_gpio; }; /* Private function for resolving node pointer to gpio_chip */ @@ -42,31 +46,41 @@ static int of_gpiochip_find_and_xlate(struct gpio_chip *gc, void *data) return false; ret = gc->of_xlate(gc, &gg_data->gpiospec, gg_data->flags); - if (ret < 0) + if (ret < 0) { + /* We've found a gpio chip, but the translation failed. + * Store translation error in out_gpio. + * Return false to keep looking, as more than one gpio chip + * could be registered per of-node. + */ + gg_data->out_gpio = ERR_PTR(ret); return false; + } - gg_data->out_gpio = ret + gc->base; + gg_data->out_gpio = gpiochip_get_desc(gc, ret); return true; } /** - * of_get_named_gpio_flags() - Get a GPIO number and flags to use with GPIO API + * of_get_named_gpiod_flags() - Get a GPIO descriptor and flags for GPIO API * @np: device node to get GPIO from * @propname: property name containing gpio specifier(s) * @index: index of the GPIO * @flags: a flags pointer to fill in * - * Returns GPIO number to use with Linux generic 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. */ -int of_get_named_gpio_flags(struct device_node *np, const char *propname, - int index, enum of_gpio_flags *flags) +struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np, + const char *propname, int index, enum of_gpio_flags *flags) { /* Return -EPROBE_DEFER to support probe() functions to be called * later when the GPIO actually becomes available */ - struct gg_data gg_data = { .flags = flags, .out_gpio = -EPROBE_DEFER }; + struct gg_data gg_data = { + .flags = flags, + .out_gpio = ERR_PTR(-EPROBE_DEFER) + }; int ret; /* .of_xlate might decide to not fill in the flags, so clear it. */ @@ -76,18 +90,139 @@ int of_get_named_gpio_flags(struct device_node *np, const char *propname, ret = of_parse_phandle_with_args(np, propname, "#gpio-cells", index, &gg_data.gpiospec); if (ret) { - pr_debug("%s: can't parse gpios property\n", __func__); - return ret; + pr_debug("%s: can't parse '%s' property of node '%s[%d]'\n", + __func__, propname, np->full_name, index); + return ERR_PTR(ret); } gpiochip_find(&gg_data, of_gpiochip_find_and_xlate); of_node_put(gg_data.gpiospec.np); - pr_debug("%s exited with status %d\n", __func__, gg_data.out_gpio); + pr_debug("%s: parsed '%s' property of node '%s[%d]' - status (%d)\n", + __func__, propname, np->full_name, index, + PTR_ERR_OR_ZERO(gg_data.out_gpio)); return gg_data.out_gpio; } + +int of_get_named_gpio_flags(struct device_node *np, const char *list_name, + int index, enum of_gpio_flags *flags) +{ + struct gpio_desc *desc; + + desc = of_get_named_gpiod_flags(np, list_name, index, flags); + + if (IS_ERR(desc)) + return PTR_ERR(desc); + else + return desc_to_gpio(desc); +} EXPORT_SYMBOL(of_get_named_gpio_flags); +/** + * of_parse_own_gpio() - Get a GPIO hog descriptor, names and flags for GPIO API + * @np: device node to get GPIO from + * @name: GPIO line name + * @lflags: gpio_lookup_flags - returned from 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 + * value on the error condition. + */ +static struct gpio_desc *of_parse_own_gpio(struct device_node *np, + const char **name, + enum gpio_lookup_flags *lflags, + enum gpiod_flags *dflags) +{ + struct device_node *chip_np; + enum of_gpio_flags xlate_flags; + struct gg_data gg_data = { + .flags = &xlate_flags, + }; + u32 tmp; + int i, ret; + + chip_np = np->parent; + if (!chip_np) + return ERR_PTR(-EINVAL); + + xlate_flags = 0; + *lflags = 0; + *dflags = 0; + + ret = of_property_read_u32(chip_np, "#gpio-cells", &tmp); + if (ret) + return ERR_PTR(ret); + + if (tmp > MAX_PHANDLE_ARGS) + return ERR_PTR(-EINVAL); + + gg_data.gpiospec.args_count = tmp; + gg_data.gpiospec.np = chip_np; + for (i = 0; i < tmp; i++) { + ret = of_property_read_u32_index(np, "gpios", i, + &gg_data.gpiospec.args[i]); + if (ret) + return ERR_PTR(ret); + } + + gpiochip_find(&gg_data, of_gpiochip_find_and_xlate); + if (!gg_data.out_gpio) { + if (np->parent == np) + return ERR_PTR(-ENXIO); + else + return ERR_PTR(-EINVAL); + } + + if (xlate_flags & OF_GPIO_ACTIVE_LOW) + *lflags |= GPIO_ACTIVE_LOW; + + if (of_property_read_bool(np, "input")) + *dflags |= GPIOD_IN; + else if (of_property_read_bool(np, "output-low")) + *dflags |= GPIOD_OUT_LOW; + else if (of_property_read_bool(np, "output-high")) + *dflags |= GPIOD_OUT_HIGH; + else { + pr_warn("GPIO line %d (%s): no hogging state specified, bailing out\n", + desc_to_gpio(gg_data.out_gpio), np->name); + return ERR_PTR(-EINVAL); + } + + if (name && of_property_read_string(np, "line-name", name)) + *name = np->name; + + return gg_data.out_gpio; +} + +/** + * of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions + * @chip: gpio chip to act on + * + * This is only used by of_gpiochip_add to request/set GPIO initial + * configuration. + */ +static void of_gpiochip_scan_gpios(struct gpio_chip *chip) +{ + struct gpio_desc *desc = NULL; + struct device_node *np; + const char *name; + enum gpio_lookup_flags lflags; + enum gpiod_flags dflags; + + for_each_child_of_node(chip->of_node, np) { + if (!of_property_read_bool(np, "gpio-hog")) + continue; + + desc = of_parse_own_gpio(np, &name, &lflags, &dflags); + if (IS_ERR(desc)) + continue; + + if (gpiod_hog(desc, name, lflags, dflags)) + continue; + } +} + /** * of_gpio_simple_xlate - translate gpio_spec to the GPIO number and flags * @gc: pointer to the gpio_chip structure @@ -104,7 +239,7 @@ int of_gpio_simple_xlate(struct gpio_chip *gc, { /* * We're discouraging gpio_cells < 2, since that way you'll have to - * write your own xlate function (that will have to retrive the GPIO + * write your own xlate function (that will have to retrieve the GPIO * number and the flags from a single gpio cell -- this is possible, * but not recommended). */ @@ -182,63 +317,136 @@ err0: } EXPORT_SYMBOL(of_mm_gpiochip_add); +/** + * of_mm_gpiochip_remove - Remove memory mapped GPIO chip (bank) + * @mm_gc: pointer to the of_mm_gpio_chip allocated structure + */ +void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc) +{ + struct gpio_chip *gc = &mm_gc->gc; + + if (!mm_gc) + return; + + gpiochip_remove(gc); + iounmap(mm_gc->regs); + kfree(gc->label); +} +EXPORT_SYMBOL(of_mm_gpiochip_remove); + #ifdef CONFIG_PINCTRL -static void of_gpiochip_add_pin_range(struct gpio_chip *chip) +static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { struct device_node *np = chip->of_node; struct of_phandle_args pinspec; struct pinctrl_dev *pctldev; int index = 0, ret; + const char *name; + static const char group_names_propname[] = "gpio-ranges-group-names"; + struct property *group_names; if (!np) - return; + return 0; + + group_names = of_find_property(np, group_names_propname, NULL); for (;; index++) { - ret = of_parse_phandle_with_args(np, "gpio-ranges", - "#gpio-range-cells", index, &pinspec); + ret = of_parse_phandle_with_fixed_args(np, "gpio-ranges", 3, + index, &pinspec); if (ret) break; pctldev = of_pinctrl_get(pinspec.np); if (!pctldev) - break; - - ret = gpiochip_add_pin_range(chip, - pinctrl_dev_get_devname(pctldev), - pinspec.args[0], - pinspec.args[1], - pinspec.args[2]); - - if (ret) - break; + return -EPROBE_DEFER; + + if (pinspec.args[2]) { + if (group_names) { + of_property_read_string_index(np, + group_names_propname, + index, &name); + if (strlen(name)) { + pr_err("%s: Group name of numeric GPIO ranges must be the empty string.\n", + np->full_name); + break; + } + } + /* npins != 0: linear range */ + ret = gpiochip_add_pin_range(chip, + pinctrl_dev_get_devname(pctldev), + pinspec.args[0], + pinspec.args[1], + pinspec.args[2]); + if (ret) + return ret; + } else { + /* npins == 0: special range */ + if (pinspec.args[1]) { + pr_err("%s: Illegal gpio-range format.\n", + np->full_name); + break; + } + + if (!group_names) { + pr_err("%s: GPIO group range requested but no %s property.\n", + np->full_name, group_names_propname); + break; + } + + ret = of_property_read_string_index(np, + group_names_propname, + index, &name); + if (ret) + break; + + if (!strlen(name)) { + pr_err("%s: Group name of GPIO group range cannot be the empty string.\n", + np->full_name); + break; + } + + ret = gpiochip_add_pingroup_range(chip, pctldev, + pinspec.args[0], name); + if (ret) + return ret; + } } + + return 0; } #else -static void of_gpiochip_add_pin_range(struct gpio_chip *chip) {} +static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { return 0; } #endif -void of_gpiochip_add(struct gpio_chip *chip) +int of_gpiochip_add(struct gpio_chip *chip) { + int status; + if ((!chip->of_node) && (chip->dev)) chip->of_node = chip->dev->of_node; if (!chip->of_node) - return; + return 0; if (!chip->of_xlate) { chip->of_gpio_n_cells = 2; chip->of_xlate = of_gpio_simple_xlate; } - of_gpiochip_add_pin_range(chip); + status = of_gpiochip_add_pin_range(chip); + if (status) + return status; + of_node_get(chip->of_node); + + of_gpiochip_scan_gpios(chip); + + return 0; } void of_gpiochip_remove(struct gpio_chip *chip) { gpiochip_remove_pin_ranges(chip); - - if (chip->of_node) - of_node_put(chip->of_node); + of_node_put(chip->of_node); }