aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/pinctrl
diff options
context:
space:
mode:
authorTimur Tabi <timur@codeaurora.org>2017-02-10 17:21:00 -0600
committerLinus Walleij <linus.walleij@linaro.org>2017-03-06 14:38:05 +0100
commit8e51533780ba223a3562ff4382c6b6f350c7e9a4 (patch)
tree02b1881346ea5ecfd25eafb2e07c38c9849b15f5 /drivers/pinctrl
parentLinux 4.11-rc1 (diff)
downloadlinux-dev-8e51533780ba223a3562ff4382c6b6f350c7e9a4.tar.xz
linux-dev-8e51533780ba223a3562ff4382c6b6f350c7e9a4.zip
pinctrl: qcom: add get_direction function
The get_direction callback function allows gpiolib to know the current direction (input vs output) for a given GPIO. This is particularly useful on ACPI systems, where the GPIOs are configured only by firmware (typically UEFI), so the only way to know the initial values to query the hardware directly. Without this function, gpiolib thinks that all GPIOs are configured for input. Signed-off-by: Timur Tabi <timur@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Diffstat (limited to 'drivers/pinctrl')
-rw-r--r--drivers/pinctrl/qcom/pinctrl-msm.c15
1 files changed, 15 insertions, 0 deletions
diff --git a/drivers/pinctrl/qcom/pinctrl-msm.c b/drivers/pinctrl/qcom/pinctrl-msm.c
index f8e9e1c2b2f6..c978be5eb9eb 100644
--- a/drivers/pinctrl/qcom/pinctrl-msm.c
+++ b/drivers/pinctrl/qcom/pinctrl-msm.c
@@ -422,6 +422,20 @@ static int msm_gpio_direction_output(struct gpio_chip *chip, unsigned offset, in
return 0;
}
+static int msm_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ struct msm_pinctrl *pctrl = gpiochip_get_data(chip);
+ const struct msm_pingroup *g;
+ u32 val;
+
+ g = &pctrl->soc->groups[offset];
+
+ val = readl(pctrl->regs + g->ctl_reg);
+
+ /* 0 = output, 1 = input */
+ return val & BIT(g->oe_bit) ? 0 : 1;
+}
+
static int msm_gpio_get(struct gpio_chip *chip, unsigned offset)
{
const struct msm_pingroup *g;
@@ -510,6 +524,7 @@ static void msm_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
static struct gpio_chip msm_gpio_template = {
.direction_input = msm_gpio_direction_input,
.direction_output = msm_gpio_direction_output,
+ .get_direction = msm_gpio_get_direction,
.get = msm_gpio_get,
.set = msm_gpio_set,
.request = gpiochip_generic_request,