diff mbox series

[v4] pinctrl: samsung: Add support for pull-up and pull-down

Message ID 20240729153631.24536-1-vishnu.reddy@samsung.com
State New
Headers show
Series [v4] pinctrl: samsung: Add support for pull-up and pull-down | expand

Commit Message

Vishnu Reddy July 29, 2024, 3:36 p.m. UTC
Gpiolib framework has the implementation of setting up the
PUD configuration for GPIO pins but there is no driver support.

Add support to handle the PUD configuration request from the
userspace in samsung pinctrl driver.

Signed-off-by: Vishnu Reddy <vishnu.reddy@samsung.com>
---
 drivers/pinctrl/samsung/pinctrl-exynos-arm.c | 14 ++++
 drivers/pinctrl/samsung/pinctrl-s3c64xx.c    | 14 ++++
 drivers/pinctrl/samsung/pinctrl-samsung.c    | 77 ++++++++++++++++++++
 drivers/pinctrl/samsung/pinctrl-samsung.h    | 21 ++++++
 4 files changed, 126 insertions(+)

Comments

Krzysztof Kozlowski Aug. 4, 2024, 2:45 p.m. UTC | #1
On 29/07/2024 17:36, Vishnu Reddy wrote:
> Gpiolib framework has the implementation of setting up the
> PUD configuration for GPIO pins but there is no driver support.
> 
> Add support to handle the PUD configuration request from the
> userspace in samsung pinctrl driver.
> 
> Signed-off-by: Vishnu Reddy <vishnu.reddy@samsung.com>
> ---

Where is the changelog? What happened with this patch?

Best regards,
Krzysztof
Vishnu Reddy Aug. 7, 2024, 3:15 a.m. UTC | #2
> -----Original Message-----
> From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Sent: 04 August 2024 20:15
> To: Vishnu Reddy <vishnu.reddy@samsung.com>;
> s.nawrocki@samsung.com; alim.akhtar@samsung.com;
> linus.walleij@linaro.org
> Cc: linux-arm-kernel@lists.infradead.org; linux-samsung-
> soc@vger.kernel.org; linux-gpio@vger.kernel.org; linux-
> kernel@vger.kernel.org; pankaj.dubey@samsung.com;
> ravi.patel@samsung.com; gost.dev@samsung.com
> Subject: Re: [PATCH v4] pinctrl: samsung: Add support for pull-up and pull-
> down
> 
> On 29/07/2024 17:36, Vishnu Reddy wrote:
> > Gpiolib framework has the implementation of setting up the PUD
> > configuration for GPIO pins but there is no driver support.
> >
> > Add support to handle the PUD configuration request from the userspace
> > in samsung pinctrl driver.
> >
> > Signed-off-by: Vishnu Reddy <vishnu.reddy@samsung.com>
> > ---
> 
> Where is the changelog? What happened with this patch?

Sorry, I missed to include changelog in all previous version of patches.
I will take care this part in future, below are the changelogs:

changes in v4:
- Update code in s5pv210_pud_value_init and s3c64xx_pud_value_init
functions for storing the pud values into array using macro names
instead of loop.
- Removed unnecessary and weird style comments.
- Updated proper comments.
- Fixed typo errors.
- Updated macro names based on suggestions which got in v3 review
comments.

changes in v3:
- Add new code to get the s5pv210 and s3c64xx and other exynos
series of pull down, pull up and disable values into an array and use
it in set config function for pud configuration.
- Add clock enable and disable setting while accessing registers.

changes in v2:
- Updated the macro names based on review comment that suggested
to follow the naming conventions according the file how previous macro
names defined.

Do let me know if I need to revise the patch or you are okay to consider
above changelog?

Regards,
Vishnu Reddy
> 
> Best regards,
> Krzysztof
diff mbox series

Patch

diff --git a/drivers/pinctrl/samsung/pinctrl-exynos-arm.c b/drivers/pinctrl/samsung/pinctrl-exynos-arm.c
index 85ddf49a5188..d3d8672f74dc 100644
--- a/drivers/pinctrl/samsung/pinctrl-exynos-arm.c
+++ b/drivers/pinctrl/samsung/pinctrl-exynos-arm.c
@@ -40,6 +40,19 @@  static const struct samsung_pin_bank_type bank_type_alive = {
 #define S5P_OTHERS_RET_MMC		(1 << 29)
 #define S5P_OTHERS_RET_UART		(1 << 28)
 
+#define S5P_PIN_PULL_DISABLE		0
+#define S5P_PIN_PULL_DOWN		1
+#define S5P_PIN_PULL_UP			2
+
+static void s5pv210_pud_value_init(struct samsung_pinctrl_drv_data *drvdata)
+{
+	unsigned int  *pud_val = drvdata->pud_val;
+
+	pud_val[PUD_PULL_DISABLE] = S5P_PIN_PULL_DISABLE;
+	pud_val[PUD_PULL_DOWN] = S5P_PIN_PULL_DOWN;
+	pud_val[PUD_PULL_UP] = S5P_PIN_PULL_UP;
+}
+
 static void s5pv210_retention_disable(struct samsung_pinctrl_drv_data *drvdata)
 {
 	void __iomem *clk_base = (void __iomem *)drvdata->retention_ctrl->priv;
@@ -133,6 +146,7 @@  static const struct samsung_pin_ctrl s5pv210_pin_ctrl[] __initconst = {
 		.nr_banks	= ARRAY_SIZE(s5pv210_pin_bank),
 		.eint_gpio_init = exynos_eint_gpio_init,
 		.eint_wkup_init = exynos_eint_wkup_init,
+		.pud_value_init	= s5pv210_pud_value_init,
 		.suspend	= exynos_pinctrl_suspend,
 		.resume		= exynos_pinctrl_resume,
 		.retention_data	= &s5pv210_retention_data,
diff --git a/drivers/pinctrl/samsung/pinctrl-s3c64xx.c b/drivers/pinctrl/samsung/pinctrl-s3c64xx.c
index c5d92db4fdb1..68715c09baa9 100644
--- a/drivers/pinctrl/samsung/pinctrl-s3c64xx.c
+++ b/drivers/pinctrl/samsung/pinctrl-s3c64xx.c
@@ -63,6 +63,10 @@ 
 #define EINT_CON_MASK		0xF
 #define EINT_CON_LEN		4
 
+#define S3C_PIN_PULL_DISABLE	0
+#define S3C_PIN_PULL_DOWN	1
+#define S3C_PIN_PULL_UP		2
+
 static const struct samsung_pin_bank_type bank_type_4bit_off = {
 	.fld_width = { 4, 1, 2, 0, 2, 2, },
 	.reg_offset = { 0x00, 0x04, 0x08, 0, 0x0c, 0x10, },
@@ -255,6 +259,15 @@  static int s3c64xx_irq_get_trigger(unsigned int type)
 	return trigger;
 }
 
+static void s3c64xx_pud_value_init(struct samsung_pinctrl_drv_data *drvdata)
+{
+	unsigned int  *pud_val = drvdata->pud_val;
+
+	pud_val[PUD_PULL_DISABLE] = S3C_PIN_PULL_DISABLE;
+	pud_val[PUD_PULL_DOWN] = S3C_PIN_PULL_DOWN;
+	pud_val[PUD_PULL_UP] = S3C_PIN_PULL_UP;
+}
+
 static void s3c64xx_irq_set_handler(struct irq_data *d, unsigned int type)
 {
 	/* Edge- and level-triggered interrupts need different handlers */
@@ -797,6 +810,7 @@  static const struct samsung_pin_ctrl s3c64xx_pin_ctrl[] __initconst = {
 		.nr_banks	= ARRAY_SIZE(s3c64xx_pin_banks0),
 		.eint_gpio_init = s3c64xx_eint_gpio_init,
 		.eint_wkup_init = s3c64xx_eint_eint0_init,
+		.pud_value_init	= s3c64xx_pud_value_init,
 	},
 };
 
diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.c b/drivers/pinctrl/samsung/pinctrl-samsung.c
index 623df65a5d6f..15aa1b71c025 100644
--- a/drivers/pinctrl/samsung/pinctrl-samsung.c
+++ b/drivers/pinctrl/samsung/pinctrl-samsung.c
@@ -997,6 +997,77 @@  static int samsung_pinctrl_unregister(struct platform_device *pdev,
 	return 0;
 }
 
+static void samsung_pud_value_init(struct samsung_pinctrl_drv_data *drvdata)
+{
+	unsigned int  *pud_val = drvdata->pud_val;
+
+	pud_val[PUD_PULL_DISABLE] = EXYNOS_PIN_PUD_PULL_DISABLE;
+	pud_val[PUD_PULL_DOWN] = EXYNOS_PIN_PID_PULL_DOWN;
+	pud_val[PUD_PULL_UP] = EXYNOS_PIN_PID_PULL_UP;
+}
+
+/*
+ * Enable or Disable the pull-down and pull-up for the gpio pins in the
+ * PUD register.
+ */
+static void samsung_gpio_set_pud(struct gpio_chip *gc, unsigned int offset,
+				 unsigned int value)
+{
+	struct samsung_pin_bank *bank = gpiochip_get_data(gc);
+	const struct samsung_pin_bank_type *type = bank->type;
+	void __iomem *reg;
+	unsigned int data, mask;
+
+	reg = bank->pctl_base + bank->pctl_offset;
+	data = readl(reg + type->reg_offset[PINCFG_TYPE_PUD]);
+	mask = (1 << type->fld_width[PINCFG_TYPE_PUD]) - 1;
+	data &= ~(mask << (offset * type->fld_width[PINCFG_TYPE_PUD]));
+	data |= value << (offset * type->fld_width[PINCFG_TYPE_PUD]);
+	writel(data, reg + type->reg_offset[PINCFG_TYPE_PUD]);
+}
+
+/*
+ * Identify the type of PUD config based on the gpiolib request to enable
+ * or disable the PUD config.
+ */
+static int samsung_gpio_set_config(struct gpio_chip *gc, unsigned int offset,
+				   unsigned long config)
+{
+	struct samsung_pin_bank *bank = gpiochip_get_data(gc);
+	struct samsung_pinctrl_drv_data *drvdata = bank->drvdata;
+	unsigned int value;
+	int ret = 0;
+	unsigned long flags;
+
+	switch (pinconf_to_config_param(config)) {
+	case PIN_CONFIG_BIAS_DISABLE:
+		value = drvdata->pud_val[PUD_PULL_DISABLE];
+		break;
+	case PIN_CONFIG_BIAS_PULL_DOWN:
+		value = drvdata->pud_val[PUD_PULL_DOWN];
+		break;
+	case PIN_CONFIG_BIAS_PULL_UP:
+		value = drvdata->pud_val[PUD_PULL_UP];
+		break;
+	default:
+		return -ENOTSUPP;
+	}
+
+	ret = clk_enable(drvdata->pclk);
+	if (ret) {
+		dev_err(drvdata->dev, "failed to enable clock\n");
+		return ret;
+	}
+
+	raw_spin_lock_irqsave(&bank->slock, flags);
+	samsung_gpio_set_pud(gc, offset, value);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
+
+	clk_disable(drvdata->pclk);
+
+	return ret;
+}
+
 static const struct gpio_chip samsung_gpiolib_chip = {
 	.request = gpiochip_generic_request,
 	.free = gpiochip_generic_free,
@@ -1006,6 +1077,7 @@  static const struct gpio_chip samsung_gpiolib_chip = {
 	.direction_output = samsung_gpio_direction_output,
 	.to_irq = samsung_gpio_to_irq,
 	.add_pin_ranges = samsung_add_pin_ranges,
+	.set_config = samsung_gpio_set_config,
 	.owner = THIS_MODULE,
 };
 
@@ -1237,6 +1309,11 @@  static int samsung_pinctrl_probe(struct platform_device *pdev)
 	if (ctrl->eint_wkup_init)
 		ctrl->eint_wkup_init(drvdata);
 
+	if (ctrl->pud_value_init)
+		ctrl->pud_value_init(drvdata);
+	else
+		samsung_pud_value_init(drvdata);
+
 	ret = samsung_gpiolib_register(pdev, drvdata);
 	if (ret)
 		goto err_unregister;
diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.h b/drivers/pinctrl/samsung/pinctrl-samsung.h
index d50ba6f07d5d..a1e7377bd890 100644
--- a/drivers/pinctrl/samsung/pinctrl-samsung.h
+++ b/drivers/pinctrl/samsung/pinctrl-samsung.h
@@ -61,6 +61,25 @@  enum pincfg_type {
 #define PIN_CON_FUNC_INPUT		0x0
 #define PIN_CON_FUNC_OUTPUT		0x1
 
+/* Values for the pin PUD register */
+#define EXYNOS_PIN_PUD_PULL_DISABLE	0x0
+#define EXYNOS_PIN_PID_PULL_DOWN	0x1
+#define EXYNOS_PIN_PID_PULL_UP		0x3
+
+/*
+ * enum pud_index - Possible index values to access the pud_val array.
+ * @PUD_PULL_DISABLE: Index for the value of pud disable
+ * @PUD_PULL_DOWN: Index for the value of pull down enable
+ * @PUD_PULL_UP: Index for the value of pull up enable
+ * @PUD_MAX: Maximum value of the index
+ */
+enum pud_index {
+	PUD_PULL_DISABLE,
+	PUD_PULL_DOWN,
+	PUD_PULL_UP,
+	PUD_MAX,
+};
+
 /**
  * enum eint_type - possible external interrupt types.
  * @EINT_TYPE_NONE: bank does not support external interrupts
@@ -261,6 +280,7 @@  struct samsung_pin_ctrl {
 
 	int		(*eint_gpio_init)(struct samsung_pinctrl_drv_data *);
 	int		(*eint_wkup_init)(struct samsung_pinctrl_drv_data *);
+	void		(*pud_value_init)(struct samsung_pinctrl_drv_data *drvdata);
 	void		(*suspend)(struct samsung_pinctrl_drv_data *);
 	void		(*resume)(struct samsung_pinctrl_drv_data *);
 };
@@ -307,6 +327,7 @@  struct samsung_pinctrl_drv_data {
 	struct samsung_pin_bank		*pin_banks;
 	unsigned int			nr_banks;
 	unsigned int			nr_pins;
+	unsigned int			pud_val[PUD_MAX];
 
 	struct samsung_retention_ctrl	*retention_ctrl;