gpio: tegra186: Add Tegra194 pin ranges for GG.0 and GG.1

The GG.0 and GG.1 GPIOs serve as CLKREQ and RST pins, respectively, for
PCIe controller 5 on Tegra194. When this controller is configured in
endpoint mode, these pins need to be used as GPIOs by the PCIe endpoint
driver. Typically the mode programming of these pins (GPIO vs. SFIO) is
performed by early boot firmware to ensure that the configuration is
consistent.

However, the GG.0 and GG.1 pins are part of a special power partition
that is not enabled during early boot, and hence the early boot firmware
cannot program these pins to be GPIOs (they are SFIO by default). Adding
them as pin ranges for the pin controller allows the pin controller to
be involved when these pins are requested as GPIOs and allows the proper
programming to take place.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200319122737.3063291-4-thierry.reding@gmail.com
Tested-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c
index 1086c1f..79b553d 100644 (file)
--- a/drivers/gpio/gpio-tegra186.c
+++ b/drivers/gpio/gpio-tegra186.c
@@ -839,11 +839,19 @@ static const struct tegra_gpio_port tegra194_main_ports[] = {
        TEGRA194_MAIN_GPIO_PORT(GG, 0, 0, 2)
 };
 
+static const struct tegra186_pin_range tegra194_main_pin_ranges[] = {
+       { TEGRA194_MAIN_GPIO(GG, 0), "pex_l5_clkreq_n_pgg0" },
+       { TEGRA194_MAIN_GPIO(GG, 1), "pex_l5_rst_n_pgg1" },
+};
+
 static const struct tegra_gpio_soc tegra194_main_soc = {
        .num_ports = ARRAY_SIZE(tegra194_main_ports),
        .ports = tegra194_main_ports,
        .name = "tegra194-gpio",
        .instance = 0,
+       .num_pin_ranges = ARRAY_SIZE(tegra194_main_pin_ranges),
+       .pin_ranges = tegra194_main_pin_ranges,
+       .pinmux = "nvidia,tegra194-pinmux",
 };
 
 #define TEGRA194_AON_GPIO_PORT(_name, _bank, _port, _pins)     \