zephyr test: Verify SYV682 FRS_EN signal

In the SYV682 emulator, only assert FRS status when FRS is enabled via
GPIO. In the test, check that FRS enable and disable updates the GPIO.

BUG=b:190519131
TEST=zmake configure --test zephyr/test/drivers
BRANCH=none

Signed-off-by: Abe Levkoy <alevkoy@chromium.org>
Change-Id: I50f640882f7e59a0e609614c400e93c75fe34e0c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3271350
Reviewed-by: Keith Short <keithshort@chromium.org>
Commit-Queue: Keith Short <keithshort@chromium.org>

5 files changed, 52 insertions, 13 deletions

diff --git a/zephyr/dts/bindings/emul/zephyr,syv682x.yaml b/zephyr/dts/bindings/emul/zephyr,syv682x.yaml
index 75de7cf743..e1ce84e85d 100644
--- a/zephyr/dts/bindings/emul/zephyr,syv682x.yaml
+++ b/zephyr/dts/bindings/emul/zephyr,syv682x.yaml
@@ -7,3 +7,9 @@ description: Zephyr SYV682X Emulator
 compatible: "zephyr,syv682x-emul"
 
 include: base.yaml
+
+properties:
+  frs_en_gpio:
+    type: phandle
+    description: The GPIO that controls FRS enable on this device
+    required: true
diff --git a/zephyr/emul/emul_syv682x.c b/zephyr/emul/emul_syv682x.c
index 2a181fea23..b9d2dc57c7 100644
--- a/zephyr/emul/emul_syv682x.c
+++ b/zephyr/emul/emul_syv682x.c
@@ -6,6 +6,8 @@
 #define DT_DRV_COMPAT zephyr_syv682x_emul
 
 #include <device.h>
+#include <devicetree/gpio.h>
+#include <drivers/gpio/gpio_emul.h>
 #include <emul.h>
 #include <drivers/i2c.h>
 #include <drivers/i2c_emul.h>
@@ -25,6 +27,8 @@ struct syv682x_emul_data {
 	struct i2c_emul emul;
 	/** Smart battery device being emulated */
 	const struct device *i2c;
+	const struct device *frs_en_gpio_port;
+	gpio_pin_t frs_en_gpio_pin;
 	/** Configuration information */
 	const struct syv682x_emul_cfg *cfg;
 	/** Current state of all emulated SYV682x registers */
@@ -62,9 +66,16 @@ int syv682x_emul_set_reg(struct i2c_emul *emul, int reg, uint8_t val)
 
 void syv682x_emul_set_status(struct i2c_emul *emul, uint8_t val)
 {
-	struct syv682x_emul_data *data;
+	struct syv682x_emul_data *data =
+		CONTAINER_OF(emul, struct syv682x_emul_data, emul);
+	int frs_en_gpio = gpio_emul_output_get(data->frs_en_gpio_port,
+			data->frs_en_gpio_pin);
+
+	/* Only assert FRS status if FRS is enabled. */
+	__ASSERT_NO_MSG(frs_en_gpio >= 0);
+	if (!frs_en_gpio)
+		val &= ~SYV682X_STATUS_FRS;
 
-	data = CONTAINER_OF(emul, struct syv682x_emul_data, emul);
 	data->status_cond = val;
 	data->reg[SYV682X_STATUS_REG] |= val;
 
@@ -79,7 +90,7 @@ void syv682x_emul_set_status(struct i2c_emul *emul, uint8_t val)
 	 * the power path off when either of these conditions occurs, and they
 	 * should quickly dissipate. If they somehow stay set, the device should
 	 * interrupt continuously. Relatedly, the emulator should only generate
-	 * an FRS alert if the EC is asserting the FRS GPIO.
+	 * an interrupt based on FRS status if the FRS enable pin was asserted.
 	 */
 }
 
@@ -257,14 +268,19 @@ static int syv682x_emul_init(const struct emul *emul,
 	return ret;
 }
 
-#define SYV682X_EMUL(n)                                                       \
-	static struct syv682x_emul_data syv682x_emul_data_##n = {};           \
-	static const struct syv682x_emul_cfg syv682x_emul_cfg_##n = {         \
-		.i2c_label = DT_INST_BUS_LABEL(n),                            \
-		.data = &syv682x_emul_data_##n,                               \
-		.addr = DT_INST_REG_ADDR(n),                                  \
-	};                                                                    \
-	EMUL_DEFINE(syv682x_emul_init, DT_DRV_INST(n), &syv682x_emul_cfg_##n, \
+#define SYV682X_EMUL(n)                                                        \
+	static struct syv682x_emul_data syv682x_emul_data_##n = {              \
+		.frs_en_gpio_port = DEVICE_DT_GET(DT_GPIO_CTLR(                \
+					DT_INST_PROP(n, frs_en_gpio), gpios)), \
+		.frs_en_gpio_pin = DT_GPIO_PIN(                                \
+				DT_INST_PROP(n, frs_en_gpio), gpios),          \
+	};                                                                     \
+	static const struct syv682x_emul_cfg syv682x_emul_cfg_##n = {          \
+		.i2c_label = DT_INST_BUS_LABEL(n),                             \
+		.data = &syv682x_emul_data_##n,                                \
+		.addr = DT_INST_REG_ADDR(n),                                   \
+	};                                                                     \
+	EMUL_DEFINE(syv682x_emul_init, DT_DRV_INST(n), &syv682x_emul_cfg_##n,  \
 		    &syv682x_emul_data_##n)
 
 DT_INST_FOREACH_STATUS_OKAY(SYV682X_EMUL)
diff --git a/zephyr/test/drivers/overlay.dts b/zephyr/test/drivers/overlay.dts
index a8b5dec4d1..c247caab05 100644
--- a/zephyr/test/drivers/overlay.dts
+++ b/zephyr/test/drivers/overlay.dts
@@ -59,6 +59,11 @@
 			enum-name = "GPIO_USB_C1_RT_RST_ODL";
 			label = "USB_C1_RT_RST_ODL";
 		};
+		gpio_usb_c1_frs_en: usb_c1_frs_en {
+			gpios = <&gpio0 8 (GPIO_OUT_LOW)>;
+			enum-name = "GPIO_USB_C1_FRS_EN";
+			label = "USB_C1_FRS_EN";
+		};
 	};
 	named-i2c-ports {
 		compatible = "named-i2c-ports";
@@ -473,6 +478,7 @@
 			compatible = "zephyr,syv682x-emul";
 			reg = <0x41>;
 			label = "SYV682X_EMUL";
+			frs_en_gpio = <&gpio_usb_c1_frs_en>;
 		};
 
 		usb_c1_bb_retimer_emul: bbretimer@42 {
@@ -512,7 +518,7 @@
 };
 
 &gpio0 {
-	ngpios = <8>;
+	ngpios = <9>;
 };
 
 &i2c0 {
diff --git a/zephyr/test/drivers/src/ppc.c b/zephyr/test/drivers/src/ppc.c
index 95c8abf564..740c7a0aea 100644
--- a/zephyr/test/drivers/src/ppc.c
+++ b/zephyr/test/drivers/src/ppc.c
@@ -3,6 +3,9 @@
  * found in the LICENSE file.
  */
 
+#include <device.h>
+#include <devicetree/gpio.h>
+#include <drivers/gpio/gpio_emul.h>
 #include <zephyr.h>
 #include <ztest.h>
 #include <ztest_assert.h>
@@ -15,6 +18,8 @@
 #include "usbc_ppc.h"
 
 #define SYV682X_ORD DT_DEP_ORD(DT_NODELABEL(syv682x_emul))
+#define GPIO_USB_C1_FRS_EN_PATH DT_PATH(named_gpios, usb_c1_frs_en)
+#define GPIO_USB_C1_FRS_EN_PORT DT_GPIO_PIN(GPIO_USB_C1_FRS_EN_PATH, gpios)
 
 static const int syv682x_port = 1;
 
@@ -200,6 +205,8 @@ static void test_ppc_syv682x_interrupt(void)
 static void test_ppc_syv682x_frs(void)
 {
 	struct i2c_emul *emul = syv682x_emul_get(SYV682X_ORD);
+	const struct device *gpio_dev =
+		DEVICE_DT_GET(DT_GPIO_CTLR(GPIO_USB_C1_FRS_EN_PATH, gpios));
 	uint8_t reg;
 
 	/*
@@ -211,6 +218,8 @@ static void test_ppc_syv682x_frs(void)
 			"PPC is sourcing VBUS after sink enabled");
 	ppc_set_polarity(syv682x_port, 0 /* CC1 */);
 	ppc_set_frs_enable(syv682x_port, true);
+	zassert_equal(gpio_emul_output_get(gpio_dev, GPIO_USB_C1_FRS_EN_PORT),
+			1, "FRS enabled, but FRS GPIO not asserted");
 	zassert_ok(syv682x_emul_get_reg(emul, SYV682X_CONTROL_4_REG, &reg),
 			"Reading CONTROL_4 failed");
 	zassert_equal(reg &
@@ -219,6 +228,8 @@ static void test_ppc_syv682x_frs(void)
 			"FRS enabled with CC1 polarity, but CONTROL_4 is 0x%x",
 			reg);
 	ppc_set_frs_enable(syv682x_port, false);
+	zassert_equal(gpio_emul_output_get(gpio_dev, GPIO_USB_C1_FRS_EN_PORT),
+			0, "FRS disabled, but FRS GPIO not deasserted");
 	zassert_ok(syv682x_emul_get_reg(emul, SYV682X_CONTROL_4_REG, &reg),
 			"Reading CONTROL_4 failed");
 	zassert_equal(reg &
diff --git a/zephyr/test/drivers/src/stubs.c b/zephyr/test/drivers/src/stubs.c
index a8a478a86f..93a4d06623 100644
--- a/zephyr/test/drivers/src/stubs.c
+++ b/zephyr/test/drivers/src/stubs.c
@@ -227,7 +227,7 @@ struct ppc_config_t ppc_chips[] = {
 	[USBC_PORT_C1] = {
 		.i2c_port = I2C_PORT_USB_C1,
 		.i2c_addr_flags = SYV682X_ADDR1_FLAGS,
-		/* TODO(b/190519131): Add FRS GPIO, test FRS */
+		.frs_en = GPIO_USB_C1_FRS_EN,
 		.drv = &syv682x_drv,
 	},
 };