diff options
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio-samsung.txt | 43 | ||||
| -rw-r--r-- | drivers/gpio/gpio-samsung.c | 63 |
2 files changed, 106 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-samsung.txt b/Documentation/devicetree/bindings/gpio/gpio-samsung.txt index 5375625e8cd..f1e5dfecf55 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-samsung.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-samsung.txt @@ -39,3 +39,46 @@ Example: #gpio-cells = <4>; gpio-controller; }; + + +Samsung S3C24XX GPIO Controller + +Required properties: +- compatible: Compatible property value should be "samsung,s3c24xx-gpio". + +- reg: Physical base address of the controller and length of memory mapped + region. + +- #gpio-cells: Should be 3. The syntax of the gpio specifier used by client nodes + should be the following with values derived from the SoC user manual. + <[phandle of the gpio controller node] + [pin number within the gpio controller] + [mux function] + [flags and pull up/down] + + Values for gpio specifier: + - Pin number: depending on the controller a number from 0 up to 15. + - Mux function: Depending on the SoC and the gpio bank the gpio can be set + as input, output or a special function + - Flags and Pull Up/Down: the values to use differ for the individual SoCs + example S3C2416/S3C2450: + 0 - Pull Up/Down Disabled. + 1 - Pull Down Enabled. + 2 - Pull Up Enabled. + Bit 16 (0x00010000) - Input is active low. + Consult the user manual for the correct values of Mux and Pull Up/Down. + +- gpio-controller: Specifies that the node is a gpio controller. +- #address-cells: should be 1. +- #size-cells: should be 1. + +Example: + + gpa: gpio-controller@56000000 { + #address-cells = <1>; + #size-cells = <1>; + compatible = "samsung,s3c24xx-gpio"; + reg = <0x56000000 0x10>; + #gpio-cells = <3>; + gpio-controller; + }; diff --git a/drivers/gpio/gpio-samsung.c b/drivers/gpio/gpio-samsung.c index ba126cc0407..f4814a889a5 100644 --- a/drivers/gpio/gpio-samsung.c +++ b/drivers/gpio/gpio-samsung.c @@ -938,6 +938,67 @@ static void __init samsung_gpiolib_add(struct samsung_gpio_chip *chip) s3c_gpiolib_track(chip); } +#if defined(CONFIG_PLAT_S3C24XX) && defined(CONFIG_OF) +static int s3c24xx_gpio_xlate(struct gpio_chip *gc, + const struct of_phandle_args *gpiospec, u32 *flags) +{ + unsigned int pin; + + if (WARN_ON(gc->of_gpio_n_cells < 3)) + return -EINVAL; + + if (WARN_ON(gpiospec->args_count < gc->of_gpio_n_cells)) + return -EINVAL; + + if (gpiospec->args[0] > gc->ngpio) + return -EINVAL; + + pin = gc->base + gpiospec->args[0]; + + if (s3c_gpio_cfgpin(pin, S3C_GPIO_SFN(gpiospec->args[1]))) + pr_warn("gpio_xlate: failed to set pin function\n"); + if (s3c_gpio_setpull(pin, gpiospec->args[2] & 0xffff)) + pr_warn("gpio_xlate: failed to set pin pull up/down\n"); + + if (flags) + *flags = gpiospec->args[2] >> 16; + + return gpiospec->args[0]; +} + +static const struct of_device_id s3c24xx_gpio_dt_match[] __initdata = { + { .compatible = "samsung,s3c24xx-gpio", }, + {} +}; + +static __init void s3c24xx_gpiolib_attach_ofnode(struct samsung_gpio_chip *chip, + u64 base, u64 offset) +{ + struct gpio_chip *gc = &chip->chip; + u64 address; + + if (!of_have_populated_dt()) + return; + + address = chip->base ? base + ((u32)chip->base & 0xfff) : base + offset; + gc->of_node = of_find_matching_node_by_address(NULL, + s3c24xx_gpio_dt_match, address); + if (!gc->of_node) { + pr_info("gpio: device tree node not found for gpio controller" + " with base address %08llx\n", address); + return; + } + gc->of_gpio_n_cells = 3; + gc->of_xlate = s3c24xx_gpio_xlate; +} +#else +static __init void s3c24xx_gpiolib_attach_ofnode(struct samsung_gpio_chip *chip, + u64 base, u64 offset) +{ + return; +} +#endif /* defined(CONFIG_PLAT_S3C24XX) && defined(CONFIG_OF) */ + static void __init s3c24xx_gpiolib_add_chips(struct samsung_gpio_chip *chip, int nr_chips, void __iomem *base) { @@ -962,6 +1023,8 @@ static void __init s3c24xx_gpiolib_add_chips(struct samsung_gpio_chip *chip, gc->direction_output = samsung_gpiolib_2bit_output; samsung_gpiolib_add(chip); + + s3c24xx_gpiolib_attach_ofnode(chip, S3C24XX_PA_GPIO, i * 0x10); } } |