• Chanho Park's avatar
    pinctrl: add a pin_base for sparse gpio-ranges · 3c739ad0
    Chanho Park authored
    This patch enables mapping a base offset of gpio ranges with
    a pin offset even if does'nt matched. A base of pinctrl_gpio_range
    means a base offset of gpio. However, we cannot convert gpio to pin
    number for sparse gpio ranges just only using a gpio base offset.
    We can convert a gpio to real pin number(even if not matched) using
    a new pin_base which means a base pin offset of requested gpio range.
    Now, the pin control subsystem passes the pin base offset to the
    pinmux driver.
    
    For example, let's assume below two gpio ranges in the system.
    
    static struct pinctrl_gpio_range gpio_range_a = {
        .name = "chip a",
        .id = 0,
        .base = 32,
        .pin_base = 32,
        .npins = 16,
        .gc = &chip_a;
    };
    
    static struct pinctrl_gpio_range gpio_range_b = {
        .name = "chip b",
        .id = 0,
        .base = 48,
        .pin_base = 64,
        .npins = 8,
        .gc = &chip_b;
    };
    
    We can calucalate a exact pin ranges even if doesn't matched with gpio ranges.
    
    chip a:
        gpio-range : [32 .. 47]
        pin-range  : [32 .. 47]
    chip b:
        gpio-range : [48 .. 55]
        pin-range  : [64 .. 71]
    Signed-off-by: default avatarChanho Park <chanho61.park@samsung.com>
    Signed-off-by: default avatarKyungmin Park <kyungmin.park@samsung.com>
    Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    3c739ad0
pinmux.c 30.1 KB