zephyr: replace the ecos kblight driver for a deshimmed one

Replace the ECOS pwm_kblight driver with one using the Zephyr APIs for
pwm and devicetree.

BRANCH=none
BUG=b:217741090
TEST=build and run on volteer, play with the keyboard backlight
TEST=zmake configure -b brya
TEST=zmake configure -b herobrine
TEST=zmake configure -b skyrim
TEST=zmake configure -b lazor
TEST=zmake configure -b npcx9
TEST=zmake configure -b npcx7
TEST=zmake configure -b nivviks
TEST=zmake configure -b nereid

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>
Change-Id: Idb58f6bbecad4337148fd6a279ef0625247df6fa
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/ec/+/3468505
Reviewed-by: Al Semjonovs <asemjonovs@google.com>
Reviewed-by: Jeremy Bettis <jbettis@chromium.org>

27 files changed, 241 insertions, 88 deletions

diff --git a/zephyr/CMakeLists.txt b/zephyr/CMakeLists.txt
index 89bcad1362..d5d1d1c667 100644
--- a/zephyr/CMakeLists.txt
+++ b/zephyr/CMakeLists.txt
@@ -268,8 +268,7 @@ zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_MKBP_INPUT_DEVICES
 zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_KEYBOARD_VIVALDI
                                                 "${PLATFORM_EC}/common/keyboard_vivaldi.c")
 zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_PWM_KBLIGHT
-                                                "${PLATFORM_EC}/common/keyboard_backlight.c"
-                                                "${PLATFORM_EC}/common/pwm_kblight.c")
+                                                "${PLATFORM_EC}/common/keyboard_backlight.c")
 zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_COMMON
                                                 "${PLATFORM_EC}/common/led_common.c")
 zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_LED_PWM
diff --git a/zephyr/drivers/CMakeLists.txt b/zephyr/drivers/CMakeLists.txt
index d246f31703..a9fab56f36 100644
--- a/zephyr/drivers/CMakeLists.txt
+++ b/zephyr/drivers/CMakeLists.txt
@@ -5,6 +5,7 @@
 add_subdirectory(cros_cbi)
 add_subdirectory(cros_flash)
 add_subdirectory(cros_kb_raw)
+add_subdirectory(cros_kblight)
 add_subdirectory(cros_rtc)
 add_subdirectory(cros_shi)
 add_subdirectory(cros_system)
diff --git a/zephyr/drivers/cros_kblight/CMakeLists.txt b/zephyr/drivers/cros_kblight/CMakeLists.txt
new file mode 100644
index 0000000000..a9e8516f85
--- /dev/null
+++ b/zephyr/drivers/cros_kblight/CMakeLists.txt
@@ -0,0 +1,5 @@
+# Copyright 2022 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+zephyr_library_sources_ifdef(CONFIG_PLATFORM_EC_PWM_KBLIGHT pwm_kblight.c)
diff --git a/zephyr/drivers/cros_kblight/pwm_kblight.c b/zephyr/drivers/cros_kblight/pwm_kblight.c
new file mode 100644
index 0000000000..0f82f3ce99
--- /dev/null
+++ b/zephyr/drivers/cros_kblight/pwm_kblight.c
@@ -0,0 +1,96 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#define DT_DRV_COMPAT cros_ec_kblight_pwm
+
+#include <devicetree.h>
+#include <drivers/pwm.h>
+#include <logging/log.h>
+
+#include "common.h"
+#include "keyboard_backlight.h"
+#include "util.h"
+
+LOG_MODULE_REGISTER(kblight, LOG_LEVEL_ERR);
+
+BUILD_ASSERT(DT_NUM_INST_STATUS_OKAY(DT_DRV_COMPAT) == 1,
+	     "Exactly one instance of cros-ec,kblight-pwm should be defined.");
+
+#define KBLIGHT_PWM_NODE DT_INST_PWMS_CTLR(0)
+#define KBLIGHT_PWM_CHANNEL DT_INST_PWMS_CHANNEL(0)
+#define KBLIGHT_PWM_FLAGS DT_INST_PWMS_FLAGS(0)
+#define KBLIGHT_PWM_PERIOD_US (USEC_PER_SEC/DT_INST_PROP(0, frequency))
+
+static bool kblight_enabled;
+static int kblight_percent;
+
+static void kblight_pwm_set_duty(int percent)
+{
+	const struct device *pwm_dev = DEVICE_DT_GET(KBLIGHT_PWM_NODE);
+	uint32_t pulse_us;
+	int rv;
+
+	if (!device_is_ready(pwm_dev)) {
+		LOG_ERR("PWM device %s not ready", pwm_dev->name);
+		return;
+	}
+
+	pulse_us = DIV_ROUND_NEAREST(KBLIGHT_PWM_PERIOD_US * percent, 100);
+
+	LOG_DBG("kblight PWM %s set percent (%d), pulse %d",
+		pwm_dev->name, percent, pulse_us);
+
+	rv = pwm_pin_set_usec(pwm_dev, KBLIGHT_PWM_CHANNEL,
+			      KBLIGHT_PWM_PERIOD_US, pulse_us,
+			      KBLIGHT_PWM_FLAGS);
+	if (rv) {
+		LOG_ERR("pwm_pin_set_usec() failed %s (%d)",
+			pwm_dev->name, rv);
+	}
+}
+
+static int kblight_pwm_set(int percent)
+{
+	kblight_percent = percent;
+	kblight_pwm_set_duty(percent);
+	return EC_SUCCESS;
+}
+
+static int kblight_pwm_get(void)
+{
+	return kblight_percent;
+}
+
+static int kblight_pwm_enable(int enable)
+{
+	kblight_enabled = enable;
+	if (enable) {
+		kblight_pwm_set_duty(kblight_percent);
+	} else {
+		/* Disable but hold kblight_percent. */
+		kblight_pwm_set_duty(0);
+	}
+	return EC_SUCCESS;
+}
+
+static int kblight_pwm_get_enabled(void)
+{
+	return kblight_enabled;
+}
+
+static int kblight_pwm_init(void)
+{
+	kblight_percent = 0;
+	kblight_pwm_enable(0);
+	return EC_SUCCESS;
+}
+
+const struct kblight_drv kblight_pwm = {
+	.init = kblight_pwm_init,
+	.set = kblight_pwm_set,
+	.get = kblight_pwm_get,
+	.enable = kblight_pwm_enable,
+	.get_enabled = kblight_pwm_get_enabled,
+};
diff --git a/zephyr/dts/bindings/keyboard/cros-ec,kblight-pwm.yaml b/zephyr/dts/bindings/keyboard/cros-ec,kblight-pwm.yaml
new file mode 100644
index 0000000000..e30e9c8bd2
--- /dev/null
+++ b/zephyr/dts/bindings/keyboard/cros-ec,kblight-pwm.yaml
@@ -0,0 +1,20 @@
+# Copyright 2022 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+description: PWM keyboard backlight configuration
+
+compatible: "cros-ec,kblight-pwm"
+
+include: base.yaml
+
+properties:
+  pwms:
+    type: phandle-array
+    required: true
+    description: PWM controlling the Keyboard backlight level.
+
+  frequency:
+    type: int
+    required: true
+    description: PWM frequency in Hz.
diff --git a/zephyr/projects/brya/brya/BUILD.py b/zephyr/projects/brya/brya/BUILD.py
index cfc07db535..13725151b8 100644
--- a/zephyr/projects/brya/brya/BUILD.py
+++ b/zephyr/projects/brya/brya/BUILD.py
@@ -12,6 +12,7 @@ register_npcx_project(
         "fan.dts",
         "gpio.dts",
         "interrupts.dts",
+        "keyboard.dts",
         "motionsense.dts",
         "pwm.dts",
         "pwm_leds.dts",
diff --git a/zephyr/projects/brya/brya/keyboard.dts b/zephyr/projects/brya/brya/keyboard.dts
new file mode 100644
index 0000000000..04ce42fa1e
--- /dev/null
+++ b/zephyr/projects/brya/brya/keyboard.dts
@@ -0,0 +1,16 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/ {
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm3 0 0>;
+		frequency = <2400>;
+	};
+};
+
+&pwm3 {
+	status = "okay";
+};
diff --git a/zephyr/projects/brya/brya/pwm.dts b/zephyr/projects/brya/brya/pwm.dts
index 210a70d874..b322912615 100644
--- a/zephyr/projects/brya/brya/pwm.dts
+++ b/zephyr/projects/brya/brya/pwm.dts
@@ -7,10 +7,6 @@
 	named-pwms {
 		compatible = "named-pwms";
 
-		kblight: kblight {
-			pwms = <&pwm3 0 0>;
-			frequency = <2400>;
-		};
 		pwm_fan: fan {
 			pwms = <&pwm5 0 0>;
 			frequency = <1000>;
@@ -18,11 +14,6 @@
 	};
 };
 
-/* Keyboard backlight */
-&pwm3 {
-	status = "okay";
-};
-
 /* Fan control */
 &pwm5 {
 	status = "okay";
diff --git a/zephyr/projects/herobrine/BUILD.py b/zephyr/projects/herobrine/BUILD.py
index ce0391df35..4fb0cebb40 100644
--- a/zephyr/projects/herobrine/BUILD.py
+++ b/zephyr/projects/herobrine/BUILD.py
@@ -15,6 +15,7 @@ def register_variant(project_name, extra_dts_overlays=(), extra_kconfig_files=()
             here / "common.dts",
             here / "i2c.dts",
             here / "interrupts.dts",
+            here / "keyboard.dts",
             here / "motionsense.dts",
             here / "pwm.dts",
             here / "switchcap.dts",
diff --git a/zephyr/projects/herobrine/keyboard.dts b/zephyr/projects/herobrine/keyboard.dts
new file mode 100644
index 0000000000..70bdc47c53
--- /dev/null
+++ b/zephyr/projects/herobrine/keyboard.dts
@@ -0,0 +1,16 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/ {
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm3 0 0>;
+		frequency = <10000>;
+	};
+};
+
+&pwm3 {
+	status = "okay";
+};
diff --git a/zephyr/projects/herobrine/pwm.dts b/zephyr/projects/herobrine/pwm.dts
index b8c6165d72..54f3a3f015 100644
--- a/zephyr/projects/herobrine/pwm.dts
+++ b/zephyr/projects/herobrine/pwm.dts
@@ -7,10 +7,6 @@
 	named-pwms {
 		compatible = "named-pwms";
 
-		kblight: kb_bl_pwm {
-			pwms = <&pwm3 0 0>;
-			frequency = <10000>;
-		};
 		displight: ecl_bl_pwm_r {
 			pwms = <&pwm5 0 0>;
 			frequency = <4800>;
@@ -18,11 +14,6 @@
 	};
 };
 
-/* Keyboard backlight */
-&pwm3 {
-	status = "okay";
-};
-
 /* Display backlight */
 &pwm5 {
 	status = "okay";
diff --git a/zephyr/projects/nissa/BUILD.py b/zephyr/projects/nissa/BUILD.py
index ab2225d499..0ba5bf2360 100644
--- a/zephyr/projects/nissa/BUILD.py
+++ b/zephyr/projects/nissa/BUILD.py
@@ -30,6 +30,7 @@ register_nissa_project(
         here / "nivviks_generated.dts",
         here / "nivviks_overlay.dts",
         here / "nivviks_motionsense.dts",
+        here / "nivviks_keyboard.dts",
     ],
     extra_kconfig_files=[here / "prj_nivviks.conf"],
 )
@@ -41,6 +42,7 @@ register_nissa_project(
         here / "nereid_generated.dts",
         here / "nereid_overlay.dts",
         here / "nereid_motionsense.dts",
+        here / "nereid_keyboard.dts",
     ],
     extra_kconfig_files=[here / "prj_nereid.conf"],
 )
diff --git a/zephyr/projects/nissa/nereid_keyboard.dts b/zephyr/projects/nissa/nereid_keyboard.dts
new file mode 100644
index 0000000000..0e3a92900b
--- /dev/null
+++ b/zephyr/projects/nissa/nereid_keyboard.dts
@@ -0,0 +1,12 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/ {
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm0 0 0>;
+		frequency = <10000>;
+	};
+};
diff --git a/zephyr/projects/nissa/nereid_overlay.dts b/zephyr/projects/nissa/nereid_overlay.dts
index abe01434fd..d101dd11f1 100644
--- a/zephyr/projects/nissa/nereid_overlay.dts
+++ b/zephyr/projects/nissa/nereid_overlay.dts
@@ -164,16 +164,6 @@
 		/delete-node/ temp_sensor_3;
 	};
 
-	/*
-	 * Alias kblist to correct node.
-	 */
-	named-pwms {
-		compatible = "named-pwms";
-
-		kblight: pwm_kb_bl {
-		};
-	};
-
 	usbc {
 		port0 {
 			bc12 {
diff --git a/zephyr/projects/nissa/nivviks_keyboard.dts b/zephyr/projects/nissa/nivviks_keyboard.dts
new file mode 100644
index 0000000000..5ef37fb216
--- /dev/null
+++ b/zephyr/projects/nissa/nivviks_keyboard.dts
@@ -0,0 +1,12 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/ {
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm6 6 0>;
+		frequency = <10000>;
+	};
+};
diff --git a/zephyr/projects/nissa/nivviks_overlay.dts b/zephyr/projects/nissa/nivviks_overlay.dts
index 9d4db52327..52906f4bb8 100644
--- a/zephyr/projects/nissa/nivviks_overlay.dts
+++ b/zephyr/projects/nissa/nivviks_overlay.dts
@@ -144,18 +144,6 @@
 		};
 	};
 
-	/*
-	 * Alias kblist to correct node.
-	 * It would be nice to use alias here, but the code
-	 * uses DT_NODELABEL to directly reference the node label.
-	 */
-	named-pwms {
-		compatible = "named-pwms";
-
-		kblight: pwm_kb_bl {
-		};
-	};
-
 	usbc {
 		port0 {
 			bc12 {
diff --git a/zephyr/projects/npcx_evb/npcx7/keyboard.dts b/zephyr/projects/npcx_evb/npcx7/keyboard.dts
index fdeee3c02c..896999d2a6 100644
--- a/zephyr/projects/npcx_evb/npcx7/keyboard.dts
+++ b/zephyr/projects/npcx_evb/npcx7/keyboard.dts
@@ -28,4 +28,14 @@
 			0xc8	/* C12 */
 			>;
 	};
+
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm2 0 0>;
+		frequency = <10000>;
+	};
+};
+
+&pwm2 {
+	status = "okay";
 };
diff --git a/zephyr/projects/npcx_evb/npcx7/pwm.dts b/zephyr/projects/npcx_evb/npcx7/pwm.dts
index 448fc53f7a..6a8029ecfe 100644
--- a/zephyr/projects/npcx_evb/npcx7/pwm.dts
+++ b/zephyr/projects/npcx_evb/npcx7/pwm.dts
@@ -11,10 +11,6 @@
 			pwms = <&pwm0 0 0>;
 			frequency = <25000>;
 		};
-		kblight: kblight {
-			pwms = <&pwm2 0 0>;
-			frequency = <10000>;
-		};
 	};
 };
 
@@ -23,8 +19,3 @@
 	status = "okay";
 	drive-open-drain;
 };
-
-/* kblight */
-&pwm2 {
-	status = "okay";
-};
diff --git a/zephyr/projects/npcx_evb/npcx9/keyboard.dts b/zephyr/projects/npcx_evb/npcx9/keyboard.dts
index fdeee3c02c..896999d2a6 100644
--- a/zephyr/projects/npcx_evb/npcx9/keyboard.dts
+++ b/zephyr/projects/npcx_evb/npcx9/keyboard.dts
@@ -28,4 +28,14 @@
 			0xc8	/* C12 */
 			>;
 	};
+
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm2 0 0>;
+		frequency = <10000>;
+	};
+};
+
+&pwm2 {
+	status = "okay";
 };
diff --git a/zephyr/projects/npcx_evb/npcx9/pwm.dts b/zephyr/projects/npcx_evb/npcx9/pwm.dts
index 448fc53f7a..6a8029ecfe 100644
--- a/zephyr/projects/npcx_evb/npcx9/pwm.dts
+++ b/zephyr/projects/npcx_evb/npcx9/pwm.dts
@@ -11,10 +11,6 @@
 			pwms = <&pwm0 0 0>;
 			frequency = <25000>;
 		};
-		kblight: kblight {
-			pwms = <&pwm2 0 0>;
-			frequency = <10000>;
-		};
 	};
 };
 
@@ -23,8 +19,3 @@
 	status = "okay";
 	drive-open-drain;
 };
-
-/* kblight */
-&pwm2 {
-	status = "okay";
-};
diff --git a/zephyr/projects/skyrim/BUILD.py b/zephyr/projects/skyrim/BUILD.py
index 4f70ff7dfe..c8c70a7c02 100644
--- a/zephyr/projects/skyrim/BUILD.py
+++ b/zephyr/projects/skyrim/BUILD.py
@@ -15,6 +15,7 @@ def register_variant(project_name):
             here / "gpio.dts",
             here / "i2c.dts",
             here / "interrupts.dts",
+            here / "keyboard.dts",
             here / "pwm.dts",
             # Project-specific DTS customizations.
             here / f"{project_name}.dts",
diff --git a/zephyr/projects/skyrim/keyboard.dts b/zephyr/projects/skyrim/keyboard.dts
new file mode 100644
index 0000000000..7c77dd2d07
--- /dev/null
+++ b/zephyr/projects/skyrim/keyboard.dts
@@ -0,0 +1,17 @@
+/* Copyright 2022 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/ {
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm1 0 0>;
+		frequency = <100>;
+	};
+};
+
+&pwm1 {
+	status = "okay";
+	clock-bus = "NPCX_CLOCK_BUS_LFCLK";
+};
diff --git a/zephyr/projects/skyrim/pwm.dts b/zephyr/projects/skyrim/pwm.dts
index 8853615074..14cba081cc 100644
--- a/zephyr/projects/skyrim/pwm.dts
+++ b/zephyr/projects/skyrim/pwm.dts
@@ -11,10 +11,6 @@
 			pwms = <&pwm0 0 0>;
 			frequency = <25000>;
 		};
-		kblight: pwm_kb_bl {
-			pwms = <&pwm1 0 0>;
-			frequency = <100>;
-		};
 		led_charge: ec_pwm_led_chrg_l {
 			pwms = <&pwm2 0 0>;
 			frequency = <100>;
@@ -32,12 +28,6 @@
 	drive-open-drain;
 };
 
-/* Keyboard backlight */
-&pwm1 {
-	status = "okay";
-	clock-bus = "NPCX_CLOCK_BUS_LFCLK";
-};
-
 /* Amber charging LED */
 &pwm2 {
 	status = "okay";
diff --git a/zephyr/projects/trogdor/lazor/keyboard.dts b/zephyr/projects/trogdor/lazor/keyboard.dts
index 1b683d0eba..4967cc161a 100644
--- a/zephyr/projects/trogdor/lazor/keyboard.dts
+++ b/zephyr/projects/trogdor/lazor/keyboard.dts
@@ -23,4 +23,14 @@
 			0xca	/* C12 */
 			>;
 	};
+
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm3 0 0>;
+		frequency = <10000>;
+	};
+};
+
+&pwm3 {
+	status = "okay";
 };
diff --git a/zephyr/projects/trogdor/lazor/pwm.dts b/zephyr/projects/trogdor/lazor/pwm.dts
index a06860d923..1cd70a3ea0 100644
--- a/zephyr/projects/trogdor/lazor/pwm.dts
+++ b/zephyr/projects/trogdor/lazor/pwm.dts
@@ -7,10 +7,6 @@
 	named-pwms {
 		compatible = "named-pwms";
 
-		kblight: kb_bl_pwm {
-			pwms = <&pwm3 0 0>;
-			frequency = <10000>;
-		};
 		displight: edp_bkltctl {
 			pwms = <&pwm5 0 0>;
 			frequency = <4800>;
@@ -18,11 +14,6 @@
 	};
 };
 
-/* Keyboard backlight */
-&pwm3 {
-	status = "okay";
-};
-
 /* Display backlight */
 &pwm5 {
 	status = "okay";
diff --git a/zephyr/projects/volteer/volteer/keyboard.dts b/zephyr/projects/volteer/volteer/keyboard.dts
index e9b5cdf0a1..4988e14e2f 100644
--- a/zephyr/projects/volteer/volteer/keyboard.dts
+++ b/zephyr/projects/volteer/volteer/keyboard.dts
@@ -25,4 +25,14 @@
 			0	/* C14 - for keypad */
 			>;
 	};
+
+	kblight {
+		compatible = "cros-ec,kblight-pwm";
+		pwms = <&pwm3 0 0>;
+		frequency = <2400>;
+	};
+};
+
+&pwm3 {
+	status = "okay";
 };
diff --git a/zephyr/projects/volteer/volteer/pwm.dts b/zephyr/projects/volteer/volteer/pwm.dts
index c0b2d6f117..4050f54889 100644
--- a/zephyr/projects/volteer/volteer/pwm.dts
+++ b/zephyr/projects/volteer/volteer/pwm.dts
@@ -7,10 +7,6 @@
 	named-pwms {
 		compatible = "named-pwms";
 
-		kblight: ec_kb_bl_pwm {
-			pwms = <&pwm3 0 0>;
-			frequency = <2400>;
-		};
 		pwm_fan: fan_pwm {
 			pwms = <&pwm5 0 0>;
 			frequency = <25000>;
@@ -18,11 +14,6 @@
 	};
 };
 
-/* Keyboard backlight */
-&pwm3 {
-	status = "okay";
-};
-
 /* Fan control */
 &pwm5 {
 	status = "okay";