From 2a88cb50f57cf010fc7d60b7e686f960417d6fd0 Mon Sep 17 00:00:00 2001
From: Jordan Yates <jordan@embeint.com>
Date: Tue, 18 Mar 2025 10:52:57 +1000
Subject: [PATCH] spi: stm32: initialise according to
 `zephyr,pm-device-runtime-auto`

Don't automatically enable device runtime PM on the SPI port just
because `PM_DEVICE_RUNTIME` is enabled. Require the user to explicitly
call `pm_device_runtime_enable` on the port, or add
`zephyr,pm-device-runtime-auto` to the devicetree node.

Through the usage of `pm_device_driver_init`, the default clock control
and pinctrl handling can all be contained in `spi_stm32_pm_action`.

Signed-off-by: Jordan Yates <jordan@embeint.com>
---
 drivers/spi/spi_ll_stm32.c | 72 +++++++++++++++-----------------------
 1 file changed, 29 insertions(+), 43 deletions(-)

diff --git a/drivers/spi/spi_ll_stm32.c b/drivers/spi/spi_ll_stm32.c
index d4a722e9df1..b1891dea1fa 100644
--- a/drivers/spi/spi_ll_stm32.c
+++ b/drivers/spi/spi_ll_stm32.c
@@ -1403,7 +1403,24 @@ static inline bool spi_stm32_is_subghzspi(const struct device *dev)
 #endif /* st_stm32_spi_subghz */
 }
 
-#ifdef CONFIG_PM_DEVICE
+static int spi_stm32_pinctrl_apply(const struct device *dev, uint8_t id)
+{
+	const struct spi_stm32_config *config = dev->config;
+	int err;
+
+	if (spi_stm32_is_subghzspi(dev)) {
+		return 0;
+	}
+
+	/* Move pins to requested state */
+	err = pinctrl_apply_state(config->pcfg, id);
+	if ((id == PINCTRL_STATE_SLEEP) && (err == -ENOENT)) {
+		/* Sleep state is optional */
+		err = 0;
+	}
+	return err;
+}
+
 static int spi_stm32_pm_action(const struct device *dev,
 			       enum pm_device_action action)
 {
@@ -1411,17 +1428,13 @@ static int spi_stm32_pm_action(const struct device *dev,
 	const struct device *const clk = DEVICE_DT_GET(STM32_CLOCK_CONTROL_NODE);
 	int err;
 
-
 	switch (action) {
 	case PM_DEVICE_ACTION_RESUME:
-		if (!spi_stm32_is_subghzspi(dev)) {
-			/* Set pins to active state */
-			err = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_DEFAULT);
-			if (err < 0) {
-				return err;
-			}
+		/* Configure pins for active mode */
+		err = spi_stm32_pinctrl_apply(dev, PINCTRL_STATE_DEFAULT);
+		if (err < 0) {
+			return err;
 		}
-
 		/* enable clock */
 		err = clock_control_on(clk, (clock_control_subsys_t)&config->pclken[0]);
 		if (err != 0) {
@@ -1436,22 +1449,12 @@ static int spi_stm32_pm_action(const struct device *dev,
 			LOG_ERR("Could not disable SPI clock");
 			return err;
 		}
-
-		if (!spi_stm32_is_subghzspi(dev)) {
-			/* Move pins to sleep state */
-			err = pinctrl_apply_state(config->pcfg, PINCTRL_STATE_SLEEP);
-			if ((err < 0) && (err != -ENOENT)) {
-				/*
-				 * If returning -ENOENT, no pins where defined for sleep mode :
-				 * Do not output on console (might sleep already) when going to
-				 * sleep,
-				 * "SPI pinctrl sleep state not available"
-				 * and don't block PM suspend.
-				 * Else return the error.
-				 */
-				return err;
-			}
-		}
+		/* Configure pins for sleep mode */
+		return spi_stm32_pinctrl_apply(dev, PINCTRL_STATE_SLEEP);
+	case PM_DEVICE_ACTION_TURN_ON:
+		/* Configure pins for sleep mode */
+		return spi_stm32_pinctrl_apply(dev, PINCTRL_STATE_SLEEP);
+	case PM_DEVICE_ACTION_TURN_OFF:
 		break;
 	default:
 		return -ENOTSUP;
@@ -1459,7 +1462,6 @@ static int spi_stm32_pm_action(const struct device *dev,
 
 	return 0;
 }
-#endif /* CONFIG_PM_DEVICE */
 
 static int spi_stm32_init(const struct device *dev)
 {
@@ -1472,13 +1474,6 @@ static int spi_stm32_init(const struct device *dev)
 		return -ENODEV;
 	}
 
-	err = clock_control_on(DEVICE_DT_GET(STM32_CLOCK_CONTROL_NODE),
-			       (clock_control_subsys_t) &cfg->pclken[0]);
-	if (err < 0) {
-		LOG_ERR("Could not enable SPI clock");
-		return err;
-	}
-
 	if (IS_ENABLED(STM32_SPI_DOMAIN_CLOCK_SUPPORT) && (cfg->pclk_len > 1)) {
 		err = clock_control_configure(DEVICE_DT_GET(STM32_CLOCK_CONTROL_NODE),
 					      (clock_control_subsys_t) &cfg->pclken[1],
@@ -1489,15 +1484,6 @@ static int spi_stm32_init(const struct device *dev)
 		}
 	}
 
-	if (!spi_stm32_is_subghzspi(dev)) {
-		/* Configure dt provided device signals when available */
-		err = pinctrl_apply_state(cfg->pcfg, PINCTRL_STATE_DEFAULT);
-		if (err < 0) {
-			LOG_ERR("SPI pinctrl setup failed (%d)", err);
-			return err;
-		}
-	}
-
 #ifdef CONFIG_SPI_STM32_INTERRUPT
 	cfg->irq_config(dev);
 #endif /* CONFIG_SPI_STM32_INTERRUPT */
@@ -1526,7 +1512,7 @@ static int spi_stm32_init(const struct device *dev)
 
 	spi_context_unlock_unconditionally(&data->ctx);
 
-	return pm_device_runtime_enable(dev);
+	return pm_device_driver_init(dev, spi_stm32_pm_action);
 }
 
 #ifdef CONFIG_SPI_STM32_INTERRUPT