[PATCH v1 4/5] pinctrl: intel: Implement high impedance support

Andy Shevchenko
2024-08-28T18:40:28Z

Implement high impedance support for Intel pin control hardware.
It allows to set high impedance and check it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/pinctrl/intel/pinctrl-intel.c | 46 +++++++++++++++++++++++++++
1 file changed, 46 insertions(+)

diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c
index 3a135cfe435f..ae30969b2dee 100644
--- a/drivers/pinctrl/intel/pinctrl-intel.c
+++ b/drivers/pinctrl/intel/pinctrl-intel.c
@@ -78,6 +78,7 @@
#define PADCFG0_GPIODIS_FULL 3
#define PADCFG0_GPIORXDIS BIT(9)
#define PADCFG0_GPIOTXDIS BIT(8)
+#define PADCFG0_GPIODIS (BIT(9) | BIT(8))
#define PADCFG0_GPIORXSTATE BIT(1)
#define PADCFG0_GPIOTXSTATE BIT(0)

@@ -654,6 +655,23 @@ static int intel_config_get_pull(struct intel_pinctrl *pctrl, unsigned int pin,
return 0;
}

+static int intel_config_get_high_impedance(struct intel_pinctrl *pctrl, unsigned int pin,
+ enum pin_config_param param, u32 *arg)
+{
+ void __iomem *padcfg0;
+ u32 value;
+
+ padcfg0 = intel_get_padcfg(pctrl, pin, PADCFG0);
+
+ scoped_guard(raw_spinlock_irqsave, &pctrl->lock)
+ value = readl(padcfg0);
+
+ if (__intel_gpio_get_direction(value) != PAD_CONNECT_NONE)
+ return -EINVAL;
+
+ return 0;
+}
+
static int intel_config_get_debounce(struct intel_pinctrl *pctrl, unsigned int pin,
enum pin_config_param param, u32 *arg)
{
@@ -697,6 +715,12 @@ static int intel_config_get(struct pinctrl_dev *pctldev, unsigned int pin,
return ret;
break;

+ case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
+ ret = intel_config_get_high_impedance(pctrl, pin, param, &arg);
+ if (ret)
+ return ret;
+ break;
+
case PIN_CONFIG_INPUT_DEBOUNCE:
ret = intel_config_get_debounce(pctrl, pin, param, &arg);
if (ret)
@@ -795,6 +819,22 @@ static int intel_config_set_pull(struct intel_pinctrl *pctrl, unsigned int pin,
return 0;
}

+static int intel_gpio_set_high_impedance(struct intel_pinctrl *pctrl, unsigned int pin)
+{
+ void __iomem *padcfg0;
+ u32 value;
+
+ padcfg0 = intel_get_padcfg(pctrl, pin, PADCFG0);
+
+ guard(raw_spinlock_irqsave)(&pctrl->lock);
+
+ value = readl(padcfg0);
+ value = __intel_gpio_set_direction(value, false, false);
+ writel(value, padcfg0);
+
+ return 0;
+}
+
static int intel_config_set_debounce(struct intel_pinctrl *pctrl,
unsigned int pin, unsigned int debounce)
{
@@ -857,6 +897,12 @@ static int intel_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
return ret;
break;

+ case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
+ ret = intel_gpio_set_high_impedance(pctrl, pin);
+ if (ret)
+ return ret;
+ break;
+
case PIN_CONFIG_INPUT_DEBOUNCE:
ret = intel_config_set_debounce(pctrl, pin,
pinconf_to_config_argument(configs[i]));
--
2.43.0.rc1.1336.g36b5255a03ac