pinctrl: tegra: Add SFIO/GPIO programming on Tegra194

Prior to Tegra186, the selection of SFIO vs. GPIO modes was done as part
of the GPIO controller's register programming. Starting with Tegra186, a
pin is configured as GPIO or SFIO with a bit in a configuration register
of the pin controller.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200319122737.3063291-10-thierry.reding@gmail.com
Tested-by: Vidya Sagar <vidyas@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/tegra/pinctrl-tegra.c

@@ -275,11 +275,57 @@ static int tegra_pinctrl_set_mux(struct pinctrl_dev *pctldev,
 	return 0;
 }
 
+static int tegra_pinctrl_gpio_request_enable(struct pinctrl_dev *pctldev,
+					     struct pinctrl_gpio_range *range,
+					     unsigned int offset)
+{
+	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+	const struct tegra_pingroup *group;
+	u32 value;
+
+	if (!pmx->soc->sfsel_in_mux)
+		return 0;
+
+	group = &pmx->soc->groups[offset];
+
+	if (group->mux_reg < 0 || group->sfsel_bit < 0)
+		return -EINVAL;
+
+	value = pmx_readl(pmx, group->mux_bank, group->mux_reg);
+	value &= ~BIT(group->sfsel_bit);
+	pmx_writel(pmx, value, group->mux_bank, group->mux_reg);
+
+	return 0;
+}
+
+static void tegra_pinctrl_gpio_disable_free(struct pinctrl_dev *pctldev,
+					    struct pinctrl_gpio_range *range,
+					    unsigned int offset)
+{
+	struct tegra_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
+	const struct tegra_pingroup *group;
+	u32 value;
+
+	if (!pmx->soc->sfsel_in_mux)
+		return;
+
+	group = &pmx->soc->groups[offset];
+
+	if (group->mux_reg < 0 || group->sfsel_bit < 0)
+		return;
+
+	value = pmx_readl(pmx, group->mux_bank, group->mux_reg);
+	value |= BIT(group->sfsel_bit);
+	pmx_writel(pmx, value, group->mux_bank, group->mux_reg);
+}
+
 static const struct pinmux_ops tegra_pinmux_ops = {
 	.get_functions_count = tegra_pinctrl_get_funcs_count,
 	.get_function_name = tegra_pinctrl_get_func_name,
 	.get_function_groups = tegra_pinctrl_get_func_groups,
 	.set_mux = tegra_pinctrl_set_mux,
+	.gpio_request_enable = tegra_pinctrl_gpio_request_enable,
+	.gpio_disable_free = tegra_pinctrl_gpio_disable_free,
 };
 
 static int tegra_pinconf_reg(struct tegra_pmx *pmx,

drivers/pinctrl/tegra/pinctrl-tegra.h

@@ -107,6 +107,7 @@ struct tegra_function {
  *			drvup, slwr, slwf, and drvtype parameters.
  * @drv_bank:		Drive fields register bank.
  * @hsm_bit:		High Speed Mode register bit.
+ * @sfsel_bit:		GPIO/SFIO selection register bit.
  * @schmitt_bit:	Schmitt register bit.
  * @lpmd_bit:		Low Power Mode register bit.
  * @drvdn_bit:		Drive Down register bit.
@@ -153,6 +154,7 @@ struct tegra_pingroup {
 	s32 ioreset_bit:6;
 	s32 rcv_sel_bit:6;
 	s32 hsm_bit:6;
+	s32 sfsel_bit:6;
 	s32 schmitt_bit:6;
 	s32 lpmd_bit:6;
 	s32 drvdn_bit:6;
@@ -192,6 +194,7 @@ struct tegra_pinctrl_soc_data {
 	bool hsm_in_mux;
 	bool schmitt_in_mux;
 	bool drvtype_in_mux;
+	bool sfsel_in_mux;
 };
 
 extern const struct dev_pm_ops tegra_pinctrl_pm;

drivers/pinctrl/tegra/pinctrl-tegra194.c

@@ -95,6 +95,7 @@ static struct tegra_function tegra194_functions[] = {
 		.tri_bit = 4,					\
 		.einput_bit = e_input,				\
 		.odrain_bit = e_od,				\
+		.sfsel_bit = 10,				\
 		.schmitt_bit = schmitt_b,			\
 		.drvtype_bit = 13,				\
 		.drv_reg = -1,					\
@@ -140,6 +141,7 @@ static const struct tegra_pinctrl_soc_data tegra194_pinctrl = {
 	.hsm_in_mux = true,
 	.schmitt_in_mux = true,
 	.drvtype_in_mux = true,
+	.sfsel_in_mux = true,
 };
 
 static int tegra194_pinctrl_probe(struct platform_device *pdev)