driver: espi: implement espi PM function

1. add cs pin as espi driver wake up reference
2. removed the unnecessary update of the cached date
3. removed the unnecessary busy wait in notify funciton

Signed-off-by: Lin Yu-Cheng <[email protected]>

Author: JasonLin-RealTek

drivers/espi/espi_realtek_rts5912.c

@@ -23,6 +23,13 @@ LOG_MODULE_REGISTER(espi, CONFIG_ESPI_LOG_LEVEL);
 #include "reg/reg_kbc.h"
 #include "reg/reg_port80.h"
 
+#ifdef CONFIG_PM
+#include "reg/reg_gpio.h"
+#include <zephyr/pm/device.h>
+#include <zephyr/pm/policy.h>
+#include "reg/reg_system.h"
+#endif
+
 BUILD_ASSERT(DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) == 1, "support only one espi compatible node");
 
 struct espi_rts5912_config {
@@ -56,6 +63,9 @@ struct espi_rts5912_config {
 	volatile struct port80_reg *const port80_reg;
 	uint32_t port80_clk_grp;
 	uint32_t port80_clk_idx;
+#endif
+#ifdef CONFIG_PM
+	struct gpio_dt_spec cs_pin;
 #endif
 	const struct device *clk_dev;
 	const struct pinctrl_dev_config *pcfg;
@@ -1197,7 +1207,6 @@ static void notify_host_warning(const struct device *dev, enum espi_vwire_signal
 	uint8_t status = 0;
 
 	espi_rts5912_receive_vwire(dev, signal, &status);
-	k_busy_wait(200);
 
 	switch (signal) {
 	case ESPI_VWIRE_SIGNAL_SUS_WARN:
@@ -1394,8 +1403,6 @@ static int espi_rts5912_send_vwire(const struct device *dev, enum espi_vwire_sig
 static int espi_rts5912_receive_vwire(const struct device *dev, enum espi_vwire_signal signal,
 				      uint8_t *level)
 {
-	const struct espi_rts5912_config *const espi_config = dev->config;
-	volatile struct espi_reg *const espi_reg = espi_config->espi_reg;
 	uint8_t vw_idx, lev_msk, valid_msk;
 	uint8_t vw_data;
 
@@ -1412,9 +1419,6 @@ static int espi_rts5912_receive_vwire(const struct device *dev, enum espi_vwire_
 		vw_data = espi_vw_ch_cached_data.idx2;
 		break;
 	case VW_CH_IDX3:
-		if (espi_vw_ch_cached_data.idx3 != espi_reg->EVIDX3) {
-			espi_vw_ch_cached_data.idx3 = espi_reg->EVIDX3;
-		}
 		vw_data = espi_vw_ch_cached_data.idx3;
 		break;
 	case VW_CH_IDX4:
@@ -1427,60 +1431,33 @@ static int espi_rts5912_receive_vwire(const struct device *dev, enum espi_vwire_
 		vw_data = espi_vw_tx_cached_data.idx6;
 		break;
 	case VW_CH_IDX7:
-		if (espi_vw_ch_cached_data.idx7 != espi_reg->EVIDX7) {
-			espi_vw_ch_cached_data.idx7 = espi_reg->EVIDX7;
-		}
 		vw_data = espi_vw_ch_cached_data.idx7;
 		break;
 	case VW_CH_IDX40:
 		vw_data = espi_vw_tx_cached_data.idx40;
 		break;
 	case VW_CH_IDX41:
-		if (espi_vw_ch_cached_data.idx41 != espi_reg->EVIDX41) {
-			espi_vw_ch_cached_data.idx41 = espi_reg->EVIDX41;
-		}
 		vw_data = espi_vw_ch_cached_data.idx41;
 		break;
 	case VW_CH_IDX42:
-		if (espi_vw_ch_cached_data.idx42 != espi_reg->EVIDX42) {
-			espi_vw_ch_cached_data.idx42 = espi_reg->EVIDX42;
-		}
 		vw_data = espi_vw_ch_cached_data.idx42;
 		break;
 	case VW_CH_IDX43:
-		if (espi_vw_ch_cached_data.idx43 != espi_reg->EVIDX43) {
-			espi_vw_ch_cached_data.idx43 = espi_reg->EVIDX43;
-		}
 		vw_data = espi_vw_ch_cached_data.idx43;
 		break;
 	case VW_CH_IDX44:
-		if (espi_vw_ch_cached_data.idx44 != espi_reg->EVIDX44) {
-			espi_vw_ch_cached_data.idx44 = espi_reg->EVIDX44;
-		}
 		vw_data = espi_vw_ch_cached_data.idx44;
 		break;
 	case VW_CH_IDX47:
-		if (espi_vw_ch_cached_data.idx47 != espi_reg->EVIDX47) {
-			espi_vw_ch_cached_data.idx47 = espi_reg->EVIDX47;
-		}
 		vw_data = espi_vw_ch_cached_data.idx47;
 		break;
 	case VW_CH_IDX4A:
-		if (espi_vw_ch_cached_data.idx4a != espi_reg->EVIDX4A) {
-			espi_vw_ch_cached_data.idx4a = espi_reg->EVIDX4A;
-		}
 		vw_data = espi_vw_ch_cached_data.idx4a;
 		break;
 	case VW_CH_IDX51:
-		if (espi_vw_ch_cached_data.idx51 != espi_reg->EVIDX51) {
-			espi_vw_ch_cached_data.idx51 = espi_reg->EVIDX51;
-		}
 		vw_data = espi_vw_ch_cached_data.idx51;
 		break;
 	case VW_CH_IDX61:
-		if (espi_vw_ch_cached_data.idx61 != espi_reg->EVIDX61) {
-			espi_vw_ch_cached_data.idx61 = espi_reg->EVIDX61;
-		}
 		vw_data = espi_vw_ch_cached_data.idx61;
 		break;
 	default:
@@ -2293,7 +2270,18 @@ static void espi_bus_reset_setup(const struct device *dev)
 		    DEVICE_DT_GET(DT_DRV_INST(0)), 0);
 	irq_enable(DT_IRQ_BY_NAME(DT_DRV_INST(0), bus_rst, irq));
 }
+#ifdef CONFIG_PM
+void espi_cs_low_isr(const struct device *port, struct gpio_callback *cb, gpio_port_pins_t pins)
+{
+	gpio_flags_t cs_pin_config;
 
+	gpio_pin_get_config(port, pins, &cs_pin_config);
+	if (cs_pin_config & GPIO_INT_ENABLE) {
+		gpio_pin_interrupt_configure(port, (find_msb_set(pins) - 1),
+					     GPIO_INT_MODE_DISABLED);
+	}
+}
+#endif
 static int espi_rts5912_init(const struct device *dev)
 {
 	const struct espi_rts5912_config *const espi_config = dev->config;
@@ -2393,13 +2381,44 @@ static int espi_rts5912_init(const struct device *dev)
 		goto exit;
 	}
 #endif
-
+#ifdef CONFIG_PM
+	static struct gpio_callback cb;
+	uint32_t cs_irq_nun = DT_IRQ_BY_NAME(DT_DRV_INST(0), cs_low, irq);
+
+	NVIC_ClearPendingIRQ(cs_irq_nun);
+	gpio_init_callback(&cb, espi_cs_low_isr, BIT(espi_config->cs_pin.pin));
+	gpio_add_callback(espi_config->cs_pin.port, &cb);
+	irq_enable(cs_irq_nun);
+#endif
 exit:
 	return rc;
 }
+#ifdef CONFIG_PM
+static inline int espi_rts5912_pm_action(const struct device *dev, enum pm_device_action action)
+{
+	const struct espi_rts5912_config *const espi_config = dev->config;
+	SYSTEM_Type *sys_reg = RTS5912_SCCON_REG_BASE;
 
-PINCTRL_DT_INST_DEFINE(0);
+	switch (action) {
+	case PM_DEVICE_ACTION_RESUME:
+		sys_reg->SLPCTRL &= ~SYSTEM_SLPCTRL_GPIOWKEN_Msk;
+		gpio_pin_interrupt_configure_dt(&espi_config->cs_pin, GPIO_INT_MODE_DISABLED);
+		break;
+	case PM_DEVICE_ACTION_SUSPEND:
+		sys_reg->SLPCTRL |= SYSTEM_SLPCTRL_GPIOWKEN_Msk;
+		gpio_pin_interrupt_configure_dt(&espi_config->cs_pin,
+						GPIO_INT_MODE_EDGE | GPIO_INT_TRIG_LOW);
+		break;
+	default:
+		return -ENOTSUP;
+	}
 
+	return 0;
+}
+PM_DEVICE_DT_INST_DEFINE(0, espi_rts5912_pm_action);
+#endif
+
+PINCTRL_DT_INST_DEFINE(0);
 static struct espi_rts5912_data espi_rts5912_data_0;
 
 static const struct espi_rts5912_config espi_rts5912_config = {
@@ -2434,10 +2453,18 @@ static const struct espi_rts5912_config espi_rts5912_config = {
 	.port80_reg = (volatile struct port80_reg *const)DT_INST_REG_ADDR_BY_NAME(0, port80),
 	.port80_clk_grp = DT_CLOCKS_CELL_BY_NAME(DT_DRV_INST(0), port80, clk_grp),
 	.port80_clk_idx = DT_CLOCKS_CELL_BY_NAME(DT_DRV_INST(0), port80, clk_idx),
+#endif
+#ifdef CONFIG_PM
+	.cs_pin = GPIO_DT_SPEC_INST_GET(0, cs_gpios),
 #endif
 	.clk_dev = DEVICE_DT_GET(DT_INST_CLOCKS_CTLR(0)),
 	.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(0),
 };
-
+#ifdef CONFIG_PM
+DEVICE_DT_INST_DEFINE(0, &espi_rts5912_init, PM_DEVICE_DT_INST_GET(0), &espi_rts5912_data_0,
+		      &espi_rts5912_config, PRE_KERNEL_2, CONFIG_ESPI_INIT_PRIORITY,
+		      &espi_rts5912_driver_api);
+#else
 DEVICE_DT_INST_DEFINE(0, &espi_rts5912_init, NULL, &espi_rts5912_data_0, &espi_rts5912_config,
 		      PRE_KERNEL_2, CONFIG_ESPI_INIT_PRIORITY, &espi_rts5912_driver_api);
+#endif

dts/arm/realtek/ec/rts5912.dtsi

@@ -171,6 +171,7 @@
 
 		espi0: espi0@400b1000 {
 			compatible = "realtek,rts5912-espi";
+			cs-gpios = <&gpioa 4 0>;
 			status = "disabled";
 
 			reg = <0x400b1000 0x200		/* espi target */
@@ -229,7 +230,7 @@
 				<216 0>, <217 0>, <218 0>,
 				<219 0>, <147 0>, <148 0>,
 				<149 0>, <152 0>, <153 0>,
-				<166 0>, <220 0>;
+				<166 0>, <220 0>, <4 0>;
 
 			interrupt-names = "bus-rst", "periph-ch", "vw-ch",
 				"vw-idx2", "vw-idx3", "vw-idx7",
@@ -244,7 +245,7 @@
 				"emi4", "emi5", "emi6",
 				"emi7", "oob_tx", "oob_rx",
 				"oob_chg", "maf_tr", "flash_chg",
-				"port80", "mbx";
+				"port80", "mbx", "cs_low";
 
 		};
 

dts/bindings/espi/realtek,rts5912-espi.yaml

@@ -17,3 +17,7 @@ properties:
 
   pinctrl-names:
     required: true
+
+  cs-gpios:
+    description: select the cs pin to support the espi wakeup
+    type: phandle-array