drivers: mipi_dbi: Add PM action for NXP driver

Add PM action for the NXP LCDIC driver so that we can
recover from a lower power mode where we lose the register
settings and we need to reconfigure the block.

Signed-off-by: Mahesh Mahadevan <[email protected]>

Author: mmahadevan108

drivers/mipi_dbi/mipi_dbi_nxp_lcdic.c

@@ -9,6 +9,8 @@
 #include <zephyr/drivers/mipi_dbi.h>
 #include <zephyr/drivers/pinctrl.h>
 #include <zephyr/drivers/clock_control.h>
+#include <zephyr/pm/device.h>
+#include <zephyr/pm/policy.h>
 #include <zephyr/drivers/spi.h>
 #include <zephyr/drivers/dma.h>
 #include <zephyr/logging/log.h>
@@ -110,6 +112,13 @@ struct mipi_dbi_lcdic_data {
 	uint8_t pixel_fmt;
 	/* Tracks TE edge setting we should use for pixel data */
 	uint8_t te_edge;
+	/* Tracks TE delay setting we should use */
+	k_timeout_t te_delay;
+	/* Flag indicates we need to reconfigure TE signal.
+	 * This is the case when we exit low power modes where we
+	 * need to configure the hardware registers.
+	 */
+	bool reconfigure_te;
 	/* Are we starting a new display frame */
 	bool new_frame;
 	const struct mipi_dbi_config *active_cfg;
@@ -418,12 +427,16 @@ static int mipi_dbi_lcdic_write_display(const struct device *dev,
 
 	ret = k_sem_take(&dev_data->lock, K_FOREVER);
 	if (ret) {
-		goto out;
+		goto release_sem;
 	}
 
+#ifdef CONFIG_PM_POLICY_DEVICE_CONSTRAINTS
+	pm_policy_device_power_lock_get(dev);
+#endif
+
 	ret = mipi_dbi_lcdic_configure(dev, dbi_config);
 	if (ret) {
-		goto out;
+		goto release_power_lock;
 	}
 
 	if (dev_data->new_frame) {
@@ -492,7 +505,7 @@ static int mipi_dbi_lcdic_write_display(const struct device *dev,
 		ret = mipi_dbi_lcdic_start_dma(dev);
 		if (ret) {
 			LOG_ERR("Could not start DMA (%d)", ret);
-			goto out;
+			goto release_power_lock;
 		}
 #else
 		/* Enable TX FIFO threshold interrupt. This interrupt
@@ -506,8 +519,19 @@ static int mipi_dbi_lcdic_write_display(const struct device *dev,
 		base->IMR &= ~interrupts;
 #endif
 		ret = k_sem_take(&dev_data->xfer_sem, K_FOREVER);
+		/* Do not release the lock from the power states.
+		 * This is released in the ISR after the transfer
+		 * is complete.
+		 */
+		goto release_sem;
 	}
-out:
+
+release_power_lock:
+#ifdef CONFIG_PM_POLICY_DEVICE_CONSTRAINTS
+	pm_policy_device_power_lock_put(dev);
+#endif
+
+release_sem:
 	k_sem_give(&dev_data->lock);
 	return ret;
 
@@ -527,12 +551,16 @@ static int mipi_dbi_lcdic_write_cmd(const struct device *dev,
 
 	ret = k_sem_take(&dev_data->lock, K_FOREVER);
 	if (ret) {
-		goto out;
+		goto release_sem;
 	}
 
+#ifdef CONFIG_PM_POLICY_DEVICE_CONSTRAINTS
+	pm_policy_device_power_lock_get(dev);
+#endif
+
 	ret = mipi_dbi_lcdic_configure(dev, dbi_config);
 	if (ret) {
-		goto out;
+		goto release_power_lock;
 	}
 
 	/* State reset is required before transfer */
@@ -580,7 +608,7 @@ static int mipi_dbi_lcdic_write_cmd(const struct device *dev,
 			ret = mipi_dbi_lcdic_start_dma(dev);
 			if (ret) {
 				LOG_ERR("Could not start DMA (%d)", ret);
-				goto out;
+				goto release_power_lock;
 			}
 		} else /* Data is not aligned */
 #endif
@@ -596,8 +624,19 @@ static int mipi_dbi_lcdic_write_cmd(const struct device *dev,
 			base->IMR &= ~interrupts;
 		}
 		ret = k_sem_take(&dev_data->xfer_sem, K_FOREVER);
+		/* Do not release the lock from the power states.
+		 * This is released in the ISR after the transfer
+		 * is complete.
+		 */
+		goto release_sem;
 	}
-out:
+
+release_power_lock:
+#ifdef CONFIG_PM_POLICY_DEVICE_CONSTRAINTS
+	pm_policy_device_power_lock_put(dev);
+#endif
+
+release_sem:
 	k_sem_give(&dev_data->lock);
 	return ret;
 }
@@ -686,12 +725,15 @@ static int mipi_dbi_lcdic_configure_te(const struct device *dev,
 	reg |= LCDIC_TE_CTRL_TTEW(ttew);
 	base->TE_CTRL = reg;
 	data->te_edge = edge;
+	data->te_delay = delay;
+	/* We should re-configure te signal when coming out of PM mode */
+	data->reconfigure_te = true;
 	return 0;
 }
 
 
 /* Initializes LCDIC peripheral */
-static int mipi_dbi_lcdic_init(const struct device *dev)
+static int mipi_dbi_lcdic_init_common(const struct device *dev)
 {
 	const struct mipi_dbi_lcdic_config *config = dev->config;
 	struct mipi_dbi_lcdic_data *data = dev->data;
@@ -714,14 +756,6 @@ static int mipi_dbi_lcdic_init(const struct device *dev)
 	if (ret) {
 		return ret;
 	}
-	ret = k_sem_init(&data->xfer_sem, 0, 1);
-	if (ret) {
-		return ret;
-	}
-	ret = k_sem_init(&data->lock, 1, 1);
-	if (ret) {
-		return ret;
-	}
 	/* Clear all interrupt flags */
 	base->ICR = LCDIC_ALL_INTERRUPTS;
 	/* Mask all interrupts */
@@ -787,6 +821,9 @@ static void mipi_dbi_lcdic_isr(const struct device *dev)
 			base->IMR |= LCDIC_ALL_INTERRUPTS;
 			/* All data has been sent. */
 			k_sem_give(&data->xfer_sem);
+#ifdef CONFIG_PM_POLICY_DEVICE_CONSTRAINTS
+			pm_policy_device_power_lock_put(dev);
+#endif
 		} else {
 			/* Command done. Queue next command */
 			data->cmd_bytes = MIN(data->xfer_bytes, LCDIC_MAX_XFER);
@@ -839,6 +876,49 @@ static void mipi_dbi_lcdic_isr(const struct device *dev)
 	}
 }
 
+static int mipi_dbi_lcdic_pm_action(const struct device *dev, enum pm_device_action action)
+{
+	struct mipi_dbi_lcdic_data *data = dev->data;
+
+	switch (action) {
+	case PM_DEVICE_ACTION_RESUME:
+		break;
+	case PM_DEVICE_ACTION_SUSPEND:
+		break;
+	case PM_DEVICE_ACTION_TURN_OFF:
+		break;
+	case PM_DEVICE_ACTION_TURN_ON:
+		mipi_dbi_lcdic_init_common(dev);
+		data->active_cfg = NULL;
+		if (data->reconfigure_te) {
+			mipi_dbi_lcdic_configure_te(dev, data->te_edge, data->te_delay);
+		}
+		break;
+	default:
+		return -ENOTSUP;
+	}
+	return 0;
+}
+
+static int mipi_dbi_lcdic_init(const struct device *dev)
+{
+	struct mipi_dbi_lcdic_data *data = dev->data;
+	int ret;
+
+	ret = k_sem_init(&data->xfer_sem, 0, 1);
+	if (ret) {
+		return ret;
+	}
+	ret = k_sem_init(&data->lock, 1, 1);
+	if (ret) {
+		return ret;
+	}
+	/* Rest of the init is done from the PM_DEVICE_TURN_ON action
+	 * which is invoked by pm_device_driver_init().
+	 */
+	return pm_device_driver_init(dev, mipi_dbi_lcdic_pm_action);
+}
+
 #ifdef CONFIG_MIPI_DBI_NXP_LCDIC_DMA
 #define LCDIC_DMA_CHANNELS(n)						\
 	.dma_stream = {							\
@@ -891,7 +971,9 @@ static void mipi_dbi_lcdic_isr(const struct device *dev)
 	static struct mipi_dbi_lcdic_data mipi_dbi_lcdic_data_##n = {	\
 		LCDIC_DMA_CHANNELS(n)					\
 	};								\
-	DEVICE_DT_INST_DEFINE(n, mipi_dbi_lcdic_init, NULL,		\
+	PM_DEVICE_DT_INST_DEFINE(n, mipi_dbi_lcdic_pm_action);		\
+	DEVICE_DT_INST_DEFINE(n, mipi_dbi_lcdic_init,			\
+			PM_DEVICE_DT_INST_GET(n),			\
 			&mipi_dbi_lcdic_data_##n,			\
 			&mipi_dbi_lcdic_config_##n,			\
 			POST_KERNEL,					\

dts/arm/nxp/nxp_rw6xx_common.dtsi

@@ -355,6 +355,7 @@
 		#size-cells = <0>;
 		clocks = <&clkctl1 MCUX_LCDIC_CLK>;
 		dmas = <&dma0 0>;
+		zephyr,disabling-power-states = <&suspend &standby>;
 		power-domains = <&power_mode3_domain>;
 	};