[PATCH v2 4/6] pinctrl: intel: Implement high impedance support

From: Andy Shevchenko
Date: Thu Aug 29 2024 - 10:04:53 EST


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@xxxxxxxxxxxxxxx>
---
drivers/pinctrl/intel/pinctrl-intel.c | 41 +++++++++++++++++++++++++++
1 file changed, 41 insertions(+)

diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c
index c6013d967fa6..46530ee6e92d 100644
--- a/drivers/pinctrl/intel/pinctrl-intel.c
+++ b/drivers/pinctrl/intel/pinctrl-intel.c
@@ -652,6 +652,23 @@ 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)
{
@@ -695,6 +712,12 @@ 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)
@@ -793,6 +816,20 @@ static int intel_config_set_pull(struct intel_pinctrl *pctrl, unsigned int pin,
return 0;
}

+static void 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);
+}
+
static int intel_config_set_debounce(struct intel_pinctrl *pctrl,
unsigned int pin, unsigned int debounce)
{
@@ -855,6 +892,10 @@ static int intel_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
return ret;
break;

+ case PIN_CONFIG_BIAS_HIGH_IMPEDANCE:
+ intel_gpio_set_high_impedance(pctrl, pin);
+ 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