[PATCH] sandbox: cros-ec: Add tests for the cros-ec-pwm driver

[Alper Nebi Yasak <alpernebiyasak@gmail.com>]

This patch lets sandbox-cros-ec emulate a limited pwm device which has
multiple channels but can only set a duty cycle for each, as the actual
EC doesn't expose any functionality or information other than that.
Mapping non-generic EC_PWM_TYPE_* values to these emulated pwm channels
is not implemented as nothing in U-Boot uses these types.

This emulated pwm is then used to test the cros-ec-pwm driver in
sandbox. Adding the cros-ec-pwm node to the sandbox test device-tree
unfortunately makes it the first pwm device, so this also touches some
other tests to make sure they still use the sandbox pwm.

Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
---
This depends on a small fix [1] for cros-ec-pwm which otherwise fails to
build.

[1] https://patchwork.ozlabs.org/project/uboot/patch/20210514134840.19380-1-alpernebiyasak at gmail.com/

 arch/sandbox/dts/test.dts          |  6 +++
 arch/sandbox/include/asm/test.h    | 10 +++++
 configs/sandbox64_defconfig        |  1 +
 configs/sandbox_defconfig          |  1 +
 configs/sandbox_flattree_defconfig |  1 +
 configs/sandbox_noinst_defconfig   |  1 +
 configs/sandbox_spl_defconfig      |  1 +
 drivers/misc/cros_ec_sandbox.c     | 47 +++++++++++++++++++++++
 test/cmd/pwm.c                     | 32 +++++++++++++++-
 test/dm/Makefile                   |  1 +
 test/dm/cros_ec_pwm.c              | 60 ++++++++++++++++++++++++++++++
 test/dm/panel.c                    |  2 +-
 test/dm/pwm.c                      |  6 ++-
 13 files changed, 164 insertions(+), 5 deletions(-)
 create mode 100644 test/dm/cros_ec_pwm.c

diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts
index 5ca3bc502a43..c684ff0b6db8 100644
--- a/arch/sandbox/dts/test.dts
+++ b/arch/sandbox/dts/test.dts
@@ -139,6 +139,12 @@
 				size = <0x10000>;
 			};
 		};
+
+		cros_ec_pwm: cros-ec-pwm {
+			compatible = "google,cros-ec-pwm";
+			#pwm-cells = <1>;
+		};
+
 	};
 
 	dsi_host: dsi_host {
diff --git a/arch/sandbox/include/asm/test.h b/arch/sandbox/include/asm/test.h
index 1cb960ac240d..dab1a4ea01b3 100644
--- a/arch/sandbox/include/asm/test.h
+++ b/arch/sandbox/include/asm/test.h
@@ -275,4 +275,14 @@ void sandbox_set_enable_memio(bool enable);
  */
 void sandbox_cros_ec_set_test_flags(struct udevice *dev, uint flags);
 
+/**
+ * sandbox_cros_ec_get_pwm_duty() - Get EC PWM config for testing purposes
+ *
+ * @dev: Device to check
+ * @index: PWM channel index
+ * @duty: Current duty cycle in 0..EC_PWM_MAX_DUTY range.
+ * @return 0 if OK, -ENOSPC if the PWM number is invalid
+ */
+int sandbox_cros_ec_get_pwm_duty(struct udevice *dev, uint index, uint *duty);
+
 #endif
diff --git a/configs/sandbox64_defconfig b/configs/sandbox64_defconfig
index 9a373bab6fe3..188ce05cfbf1 100644
--- a/configs/sandbox64_defconfig
+++ b/configs/sandbox64_defconfig
@@ -186,6 +186,7 @@ CONFIG_REGULATOR_S5M8767=y
 CONFIG_DM_REGULATOR_SANDBOX=y
 CONFIG_REGULATOR_TPS65090=y
 CONFIG_DM_PWM=y
+CONFIG_PWM_CROS_EC=y
 CONFIG_PWM_SANDBOX=y
 CONFIG_RAM=y
 CONFIG_REMOTEPROC_SANDBOX=y
diff --git a/configs/sandbox_defconfig b/configs/sandbox_defconfig
index bdbf714e2bd9..6c7a2f02718b 100644
--- a/configs/sandbox_defconfig
+++ b/configs/sandbox_defconfig
@@ -223,6 +223,7 @@ CONFIG_DM_REGULATOR_SANDBOX=y
 CONFIG_REGULATOR_TPS65090=y
 CONFIG_DM_REGULATOR_SCMI=y
 CONFIG_DM_PWM=y
+CONFIG_PWM_CROS_EC=y
 CONFIG_PWM_SANDBOX=y
 CONFIG_RAM=y
 CONFIG_REMOTEPROC_SANDBOX=y
diff --git a/configs/sandbox_flattree_defconfig b/configs/sandbox_flattree_defconfig
index 853c9440ea02..0844d6ec23eb 100644
--- a/configs/sandbox_flattree_defconfig
+++ b/configs/sandbox_flattree_defconfig
@@ -163,6 +163,7 @@ CONFIG_REGULATOR_S5M8767=y
 CONFIG_DM_REGULATOR_SANDBOX=y
 CONFIG_REGULATOR_TPS65090=y
 CONFIG_DM_PWM=y
+CONFIG_PWM_CROS_EC=y
 CONFIG_PWM_SANDBOX=y
 CONFIG_RAM=y
 CONFIG_REMOTEPROC_SANDBOX=y
diff --git a/configs/sandbox_noinst_defconfig b/configs/sandbox_noinst_defconfig
index c7fc98b5569a..629bde1f7ed6 100644
--- a/configs/sandbox_noinst_defconfig
+++ b/configs/sandbox_noinst_defconfig
@@ -181,6 +181,7 @@ CONFIG_REGULATOR_S5M8767=y
 CONFIG_DM_REGULATOR_SANDBOX=y
 CONFIG_REGULATOR_TPS65090=y
 CONFIG_DM_PWM=y
+CONFIG_PWM_CROS_EC=y
 CONFIG_PWM_SANDBOX=y
 CONFIG_RAM=y
 CONFIG_REMOTEPROC_SANDBOX=y
diff --git a/configs/sandbox_spl_defconfig b/configs/sandbox_spl_defconfig
index 87223a54d873..aa629e231753 100644
--- a/configs/sandbox_spl_defconfig
+++ b/configs/sandbox_spl_defconfig
@@ -183,6 +183,7 @@ CONFIG_REGULATOR_S5M8767=y
 CONFIG_DM_REGULATOR_SANDBOX=y
 CONFIG_REGULATOR_TPS65090=y
 CONFIG_DM_PWM=y
+CONFIG_PWM_CROS_EC=y
 CONFIG_PWM_SANDBOX=y
 CONFIG_RAM=y
 CONFIG_REMOTEPROC_SANDBOX=y
diff --git a/drivers/misc/cros_ec_sandbox.c b/drivers/misc/cros_ec_sandbox.c
index bc01df0904eb..db5e3b0f51a2 100644
--- a/drivers/misc/cros_ec_sandbox.c
+++ b/drivers/misc/cros_ec_sandbox.c
@@ -64,6 +64,7 @@ struct ec_keymatrix_entry {
 
 enum {
 	VSTORE_SLOT_COUNT	= 4,
+	PWM_CHANNEL_COUNT	= 4,
 };
 
 struct vstore_slot {
@@ -71,6 +72,10 @@ struct vstore_slot {
 	u8 data[EC_VSTORE_SLOT_SIZE];
 };
 
+struct ec_pwm_channel {
+	uint duty;	/* not ns, EC_PWM_MAX_DUTY = 100% */
+};
+
 /**
  * struct ec_state - Information about the EC state
  *
@@ -85,6 +90,7 @@ struct vstore_slot {
  * @recovery_req: Keyboard recovery requested
  * @test_flags: Flags that control behaviour for tests
  * @slot_locked: Locked vstore slots (mask)
+ * @pwm: Information per PWM channel
  */
 struct ec_state {
 	u8 vbnv_context[EC_VBNV_BLOCK_SIZE_V2];
@@ -98,6 +104,7 @@ struct ec_state {
 	bool recovery_req;
 	uint test_flags;
 	struct vstore_slot slot[VSTORE_SLOT_COUNT];
+	struct ec_pwm_channel pwm[PWM_CHANNEL_COUNT];
 } s_state, *g_state;
 
 /**
@@ -554,6 +561,33 @@ static int process_cmd(struct ec_state *ec,
 		len = sizeof(*resp);
 		break;
 	}
+	case EC_CMD_PWM_GET_DUTY: {
+		const struct ec_params_pwm_get_duty *req = req_data;
+		struct ec_response_pwm_get_duty *resp = resp_data;
+		struct ec_pwm_channel *pwm;
+
+		if (req->pwm_type != EC_PWM_TYPE_GENERIC)
+			return -EINVAL;
+		if (req->index >= PWM_CHANNEL_COUNT)
+			return -EINVAL;
+		pwm = &ec->pwm[req->index];
+		resp->duty = pwm->duty;
+		len = sizeof(*resp);
+		break;
+	}
+	case EC_CMD_PWM_SET_DUTY: {
+		const struct ec_params_pwm_set_duty *req = req_data;
+		struct ec_pwm_channel *pwm;
+
+		if (req->pwm_type != EC_PWM_TYPE_GENERIC)
+			return -EINVAL;
+		if (req->index >= PWM_CHANNEL_COUNT)
+			return -EINVAL;
+		pwm = &ec->pwm[req->index];
+		pwm->duty = req->duty;
+		len = 0;
+		break;
+	}
 	default:
 		printf("   ** Unknown EC command %#02x\n", req_hdr->command);
 		return -1;
@@ -619,6 +653,19 @@ void sandbox_cros_ec_set_test_flags(struct udevice *dev, uint flags)
 	ec->test_flags = flags;
 }
 
+int sandbox_cros_ec_get_pwm_duty(struct udevice *dev, uint index, uint *duty)
+{
+	struct ec_state *ec = dev_get_priv(dev);
+	struct ec_pwm_channel *pwm;
+
+	if (index >= PWM_CHANNEL_COUNT)
+		return -ENOSPC;
+	pwm = &ec->pwm[index];
+	*duty = pwm->duty;
+
+	return 0;
+}
+
 int cros_ec_probe(struct udevice *dev)
 {
 	struct ec_state *ec = dev_get_priv(dev);
diff --git a/test/cmd/pwm.c b/test/cmd/pwm.c
index 5343af83fa34..2fc0b5e40704 100644
--- a/test/cmd/pwm.c
+++ b/test/cmd/pwm.c
@@ -18,16 +18,20 @@ static int dm_test_pwm_cmd(struct unit_test_state *uts)
 {
 	struct udevice *dev;
 
+	/* cros-ec-pwm */
 	ut_assertok(uclass_get_device(UCLASS_PWM, 0, &dev));
 	ut_assertnonnull(dev);
 
 	ut_assertok(console_record_reset_enable());
 
 	/* pwm <invert> <pwm_dev_num> <channel> <polarity> */
-	ut_assertok(run_command("pwm invert 0 0 1", 0));
+	/* cros-ec-pwm doesn't support invert */
+	ut_asserteq(1, run_command("pwm invert 0 0 1", 0));
+	ut_assert_nextline("error(-38)")
 	ut_assert_console_end();
 
-	ut_assertok(run_command("pwm invert 0 0 0", 0));
+	ut_asserteq(1, run_command("pwm invert 0 0 0", 0));
+	ut_assert_nextline("error(-38)")
 	ut_assert_console_end();
 
 	/* pwm <config> <pwm_dev_num> <channel> <period_ns> <duty_ns> */
@@ -41,6 +45,30 @@ static int dm_test_pwm_cmd(struct unit_test_state *uts)
 	ut_assertok(run_command("pwm disable 0 0", 0));
 	ut_assert_console_end();
 
+	/* sandbox-pwm */
+	ut_assertok(uclass_get_device(UCLASS_PWM, 1, &dev));
+	ut_assertnonnull(dev);
+
+	ut_assertok(console_record_reset_enable());
+
+	/* pwm <invert> <pwm_dev_num> <channel> <polarity> */
+	ut_assertok(run_command("pwm invert 1 0 1", 0));
+	ut_assert_console_end();
+
+	ut_assertok(run_command("pwm invert 1 0 0", 0));
+	ut_assert_console_end();
+
+	/* pwm <config> <pwm_dev_num> <channel> <period_ns> <duty_ns> */
+	ut_assertok(run_command("pwm config 1 0 10 50", 0));
+	ut_assert_console_end();
+
+	/* pwm <enable/disable> <pwm_dev_num> <channel> */
+	ut_assertok(run_command("pwm enable 1 0", 0));
+	ut_assert_console_end();
+
+	ut_assertok(run_command("pwm disable 1 0", 0));
+	ut_assert_console_end();
+
 	return 0;
 }
 
diff --git a/test/dm/Makefile b/test/dm/Makefile
index c9644617a1fe..9ef9171a1cbc 100644
--- a/test/dm/Makefile
+++ b/test/dm/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_DM_BOOTCOUNT) += bootcount.o
 obj-$(CONFIG_CLK) += clk.o clk_ccf.o
 obj-$(CONFIG_CPU) += cpu.o
 obj-$(CONFIG_CROS_EC) += cros_ec.o
+obj-$(CONFIG_PWM_CROS_EC) += cros_ec_pwm.o
 obj-$(CONFIG_DEVRES) += devres.o
 obj-$(CONFIG_DMA) += dma.o
 obj-$(CONFIG_VIDEO_MIPI_DSI) += dsi_host.o
diff --git a/test/dm/cros_ec_pwm.c b/test/dm/cros_ec_pwm.c
new file mode 100644
index 000000000000..f8d6e1e6c40f
--- /dev/null
+++ b/test/dm/cros_ec_pwm.c
@@ -0,0 +1,60 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include <common.h>
+#include <cros_ec.h>
+#include <dm.h>
+#include <pwm.h>
+#include <asm/test.h>
+#include <dm/test.h>
+#include <test/test.h>
+#include <test/ut.h>
+
+static int dm_test_cros_ec_pwm(struct unit_test_state *uts)
+{
+	struct udevice *pwm;
+	struct udevice *ec;
+	uint duty;
+
+	ut_assertok(uclass_get_device_by_name(UCLASS_PWM, "cros-ec-pwm", &pwm));
+	ut_assertnonnull(pwm);
+	ec = dev_get_parent(pwm);
+	ut_assertnonnull(ec);
+
+	ut_assertok(pwm_set_config(pwm, 0, 100, 50));
+	ut_assertok(pwm_set_enable(pwm, 0, true));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 0, &duty));
+	ut_asserteq(50 * EC_PWM_MAX_DUTY / 100, duty);
+
+	ut_assertok(pwm_set_config(pwm, 0, 15721, 2719));
+	ut_assertok(pwm_set_enable(pwm, 0, true));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 0, &duty));
+	ut_asserteq(2719 * EC_PWM_MAX_DUTY / 15721, duty);
+
+	ut_assertok(pwm_set_enable(pwm, 0, false));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 0, &duty));
+	ut_asserteq(0, duty);
+
+	ut_assertok(pwm_set_enable(pwm, 0, true));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 0, &duty));
+	ut_asserteq(2719 * EC_PWM_MAX_DUTY / 15721, duty);
+
+	ut_assertok(pwm_set_config(pwm, 1, 1000, 0));
+	ut_assertok(pwm_set_enable(pwm, 1, true));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 1, &duty));
+	ut_asserteq(0, duty);
+
+	ut_assertok(pwm_set_config(pwm, 2, 1000, 1024));
+	ut_assertok(pwm_set_enable(pwm, 2, true));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 2, &duty));
+	ut_asserteq(EC_PWM_MAX_DUTY, duty);
+
+	ut_assertok(pwm_set_config(pwm, 3, EC_PWM_MAX_DUTY, 0xABCD));
+	ut_assertok(pwm_set_enable(pwm, 3, true));
+	ut_assertok(sandbox_cros_ec_get_pwm_duty(ec, 3, &duty));
+	ut_asserteq(0xABCD, duty);
+
+	ut_asserteq(-EINVAL, pwm_set_enable(pwm, 4, true));
+
+	return 0;
+}
+DM_TEST(dm_test_cros_ec_pwm, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);
diff --git a/test/dm/panel.c b/test/dm/panel.c
index 49f5ac7169d3..4d435a0d255c 100644
--- a/test/dm/panel.c
+++ b/test/dm/panel.c
@@ -28,7 +28,7 @@ static int dm_test_panel(struct unit_test_state *uts)
 	bool polarity;
 
 	ut_assertok(uclass_first_device_err(UCLASS_PANEL, &dev));
-	ut_assertok(uclass_first_device_err(UCLASS_PWM, &pwm));
+	ut_assertok(uclass_get_device_by_name(UCLASS_PWM, "pwm", &pwm));
 	ut_assertok(uclass_get_device(UCLASS_GPIO, 1, &gpio));
 	ut_assertok(regulator_get_by_platname("VDD_EMMC_1.8V", &reg));
 	ut_assertok(sandbox_pwm_get_config(pwm, 0, &period_ns, &duty_ns,
diff --git a/test/dm/pwm.c b/test/dm/pwm.c
index b624cf3d6558..dff626c771ac 100644
--- a/test/dm/pwm.c
+++ b/test/dm/pwm.c
@@ -20,7 +20,7 @@ static int dm_test_pwm_base(struct unit_test_state *uts)
 	bool enable;
 	bool polarity;
 
-	ut_assertok(uclass_get_device(UCLASS_PWM, 0, &dev));
+	ut_assertok(uclass_get_device_by_name(UCLASS_PWM, "pwm", &dev));
 	ut_assertnonnull(dev);
 	ut_assertok(pwm_set_config(dev, 0, 100, 50));
 	ut_assertok(pwm_set_enable(dev, 0, true));
@@ -35,8 +35,10 @@ static int dm_test_pwm_base(struct unit_test_state *uts)
 	ut_asserteq(period_ns, 4096);
 	ut_asserteq(duty_ns, 50 * 4096 / 100);
 
+	ut_assertok(uclass_get_device(UCLASS_PWM, 0, &dev));
 	ut_assertok(uclass_get_device(UCLASS_PWM, 1, &dev));
-	ut_asserteq(-ENODEV, uclass_get_device(UCLASS_PWM, 2, &dev));
+	ut_assertok(uclass_get_device(UCLASS_PWM, 2, &dev));
+	ut_asserteq(-ENODEV, uclass_get_device(UCLASS_PWM, 3, &dev));
 
 	return 0;
 }
-- 
2.31.1