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pinctrl: qcom: add get_direction function

PATCH New Timur Tabi 2 participants 2 messages Feb 10, 2017 – Feb 13, 2017

Subsystems (5)
Arm Qualcomm mailing list GPIO Pin control Pin controller - Qualcomm +1 more subsystems
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Timur Tabi

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#0 lore raw

PATCH v2 1/1 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 <[email protected]>

---

v2: Use GPIOF_DIR_IN and GPIOF_DIR_OUT

 drivers/pinctrl/qcom/pinctrl-msm.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
drivers/pinctrl/qcom/pinctrl-msm.c +14 -0
index f8e9e1c..1dae9f3 100644
@@ -422,6 +422,19 @@ 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);
+
+	return val & BIT(g->oe_bit) ? GPIOF_DIR_OUT : GPIOF_DIR_IN;
+}
+
 static int msm_gpio_get(struct gpio_chip *chip, unsigned offset)
 {
 	const struct msm_pingroup *g;

@@ -510,6 +523,7 @@ 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,
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Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm
Technologies, Inc.  Qualcomm Technologies, Inc. is a member of the
Code Aurora Forum, a Linux Foundation Collaborative Project.
#1 lore raw

PATCH v2 1/1 pinctrl: qcom: add get_direction function

Quoted 10 lines · Timur Tabi

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 <[email protected]>
Reviewed-by Stephen Boyd <[email protected]>
Signature · 2 lines
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project