[PATCH 0/2] Add pinctrl_pm_select_init_state helper function

[PATCH 0/2] Add pinctrl_pm_select_init_state helper function

[Christian Bruel]

Some platforms need to set the pinctrl to an initial state during
pm_resume, just like in probe. To achieve this, the function
pinctrl_pm_select_init_state is added.

This allows a driver to balance pinctrl_pm_select_sleep_state()
with pinctrl_pm_select_default_state() and
pinctrl_pm_select_init_state() in pm_runtime_suspend and pm_runtime_resume.

Christian Bruel (2):
  pinctrl: Add pinctrl_pm_select_init_state helper function
  PCI: stm32: use pinctrl_pm_select_init_state() in
    stm32_pcie_resume_noirq()

 drivers/pci/controller/dwc/pcie-stm32.c | 10 +++++++---
 drivers/pinctrl/core.c                  | 13 +++++++++++++
 include/linux/pinctrl/consumer.h        | 10 ++++++++++
 3 files changed, 30 insertions(+), 3 deletions(-)


base-commit: 5a972a01e24b278f7302a834c6eaee5bdac12843
-- 
2.34.1

[PATCH 1/2] pinctrl: Add pinctrl_pm_select_init_state helper function

[Christian Bruel]

If a platform requires an initial state during probing, this helper function
provides the client with access to the same initial state used to balance
from a pinctrl_pm_select_sleep_state .
eg:

 xxx_suspend_noirq
    pinctrl_pm_select_sleep_state

 xxx resume_noirq
    pinctrl_pm_select_init_state
    ...
    pinctrl_pm_select_default_state

Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
---
 drivers/pinctrl/core.c           | 13 +++++++++++++
 include/linux/pinctrl/consumer.h | 10 ++++++++++
 2 files changed, 23 insertions(+)

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 9046292d1360..80cf9f20f626 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -1655,6 +1655,19 @@ int pinctrl_pm_select_default_state(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(pinctrl_pm_select_default_state);
 
+/**
+ * pinctrl_pm_select_init_state() - select init pinctrl state for PM
+ * @dev: device to select init state for
+ */
+int pinctrl_pm_select_init_state(struct device *dev)
+{
+	if (!dev->pins)
+		return 0;
+
+	return pinctrl_select_bound_state(dev, dev->pins->init_state);
+}
+EXPORT_SYMBOL_GPL(pinctrl_pm_select_init_state);
+
 /**
  * pinctrl_pm_select_sleep_state() - select sleep pinctrl state for PM
  * @dev: device to select sleep state for
diff --git a/include/linux/pinctrl/consumer.h b/include/linux/pinctrl/consumer.h
index 73de70362b98..63ce16191eb9 100644
--- a/include/linux/pinctrl/consumer.h
+++ b/include/linux/pinctrl/consumer.h
@@ -48,6 +48,7 @@ int pinctrl_select_default_state(struct device *dev);
 
 #ifdef CONFIG_PM
 int pinctrl_pm_select_default_state(struct device *dev);
+int pinctrl_pm_select_init_state(struct device *dev);
 int pinctrl_pm_select_sleep_state(struct device *dev);
 int pinctrl_pm_select_idle_state(struct device *dev);
 #else
@@ -55,6 +56,10 @@ static inline int pinctrl_pm_select_default_state(struct device *dev)
 {
 	return 0;
 }
+static inline int pinctrl_pm_select_init_state(struct device *dev)
+{
+	return 0;
+}
 static inline int pinctrl_pm_select_sleep_state(struct device *dev)
 {
 	return 0;
@@ -143,6 +148,11 @@ static inline int pinctrl_pm_select_default_state(struct device *dev)
 	return 0;
 }
 
+static inline int pinctrl_pm_select_init_state(struct device *dev)
+{
+	return 0;
+}
+
 static inline int pinctrl_pm_select_sleep_state(struct device *dev)
 {
 	return 0;
-- 
2.34.1

[PATCH 2/2] PCI: stm32: use pinctrl_pm_select_init_state() in stm32_pcie_resume_noirq()

[Christian Bruel]

Replace direct access to dev->pins->init_state with the new helper
pinctrl_pm_select_init_state() to select the init pinctrl state.
This fixes build issues when CONFIG_PINCTRL is not defined.

Signed-off-by: Christian Bruel <christian.bruel@foss.st.com>
Reported-by: Bjorn Helgaas <bhelgaas@google.com>  
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202506260920.bmQ9hQ9s-lkp@intel.com/
Fixes: 633f42f48af5 ("PCI: stm32: Add PCIe host support for STM32MP25")
---
 drivers/pci/controller/dwc/pcie-stm32.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/pci/controller/dwc/pcie-stm32.c b/drivers/pci/controller/dwc/pcie-stm32.c
index 50fae5f5ced2..c1d803dc3778 100644
--- a/drivers/pci/controller/dwc/pcie-stm32.c
+++ b/drivers/pci/controller/dwc/pcie-stm32.c
@@ -28,6 +28,7 @@ struct stm32_pcie {
 	struct clk *clk;
 	struct gpio_desc *perst_gpio;
 	struct gpio_desc *wake_gpio;
+	bool   have_pinctrl_init;
 };
 
 static void stm32_pcie_deassert_perst(struct stm32_pcie *stm32_pcie)
@@ -91,10 +92,10 @@ static int stm32_pcie_resume_noirq(struct device *dev)
 	/*
 	 * The core clock is gated with CLKREQ# from the COMBOPHY REFCLK,
 	 * thus if no device is present, must force it low with an init pinmux
-	 * to be able to access the DBI registers.
+	 * if present to be able to access the DBI registers.
 	 */
-	if (!IS_ERR(dev->pins->init_state))
-		ret = pinctrl_select_state(dev->pins->p, dev->pins->init_state);
+	if (stm32_pcie->have_pinctrl_init)
+		ret = pinctrl_pm_select_init_state(dev);
 	else
 		ret = pinctrl_pm_select_default_state(dev);
 
@@ -274,6 +275,9 @@ static int stm32_pcie_probe(struct platform_device *pdev)
 		return dev_err_probe(dev, PTR_ERR(stm32_pcie->rst),
 				     "Failed to get PCIe reset\n");
 
+	if (device_property_match_string(dev, "pinctrl-names", PINCTRL_STATE_INIT) >= 0)
+		stm32_pcie->have_pinctrl_init = true;
+
 	ret = stm32_pcie_parse_port(stm32_pcie);
 	if (ret)
 		return ret;
-- 
2.34.1