kblight: Add keyboard backlight control module

This patch promotes board/nami/keyboard_backlight.c to common
directory.
Board customization is done via board_kblight_init callback.
It currently supports two drivers: direct PWM control and lm3509.

Signed-off-by: Daisuke Nojiri <dnojiri@chromium.org>

BUG=b:78360907,b:78141647
BRANCH=none
TEST=On Nami (for lm3509) and Sona (pwm), verify the followings:
1. Alt + brightness up/down works
2. After suspend-resume, brightness is restored
3. Lid close/open
4. After screen is off, keyboard backlight is turned off

Change-Id: I584c06e8702fe7b289999698f277311cfd3400bd
Reviewed-on: https://chromium-review.googlesource.com/1051027
Commit-Ready: Daisuke Nojiri <dnojiri@chromium.org>
Tested-by: Daisuke Nojiri <dnojiri@chromium.org>
Reviewed-by: Daisuke Nojiri <dnojiri@chromium.org>

1 files changed, 149 insertions, 0 deletions

diff --git a/common/keyboard_backlight.c b/common/keyboard_backlight.c
new file mode 100644
index 0000000000..d17c2bd319
--- /dev/null
+++ b/common/keyboard_backlight.c
@@ -0,0 +1,149 @@
+/* Copyright 2018 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.
+ */
+
+#include "console.h"
+#include "ec_commands.h"
+#include "hooks.h"
+#include "host_command.h"
+#include "keyboard_backlight.h"
+#include "lid_switch.h"
+#include "timer.h"
+#include "util.h"
+
+#define CPRINTF(format, args...) cprintf(CC_KEYBOARD, format, ## args)
+#define CPRINTS(format, args...) cprints(CC_KEYBOARD, format, ## args)
+
+static struct kblight_conf kblight;
+static int current_percent;
+
+void __attribute__((weak)) board_kblight_init(void)
+{ }
+
+static int kblight_init(void)
+{
+	if (!kblight.drv || !kblight.drv->init)
+		return EC_ERROR_UNIMPLEMENTED;
+	return kblight.drv->init();
+}
+
+static void kblight_set_deferred(void)
+{
+	if (!kblight.drv || !kblight.drv->set)
+		return;
+	kblight.drv->set(current_percent);
+}
+DECLARE_DEFERRED(kblight_set_deferred);
+
+/*
+ * APIs
+ */
+int kblight_set(int percent)
+{
+	if (current_percent < 0 || 100 < current_percent)
+		return EC_ERROR_INVAL;
+	current_percent = percent;
+	/* Need to defer i2c in case it's called from an interrupt handler. */
+	hook_call_deferred(&kblight_set_deferred_data, 0);
+	return EC_SUCCESS;
+}
+
+int kblight_get(void)
+{
+	return current_percent;
+}
+
+int kblight_enable(int enable)
+{
+	if (!kblight.drv || !kblight.drv->enable)
+		return -1;
+	return kblight.drv->enable(enable);
+}
+
+int kblight_register(const struct kblight_drv *drv)
+{
+	kblight.drv = drv;
+	CPRINTS("kblight registered");
+	return EC_SUCCESS;
+}
+
+/*
+ * Hooks
+ */
+static void keyboard_backlight_init(void)
+{
+	/* Uses PWM by default. Can be customized by board_kblight_init */
+	kblight_register(&kblight_pwm);
+	board_kblight_init();
+	if (kblight_init())
+		CPRINTS("kblight init failed");
+}
+DECLARE_HOOK(HOOK_INIT, keyboard_backlight_init, HOOK_PRIO_DEFAULT);
+
+static void kblight_suspend(void)
+{
+	kblight_enable(0);
+}
+DECLARE_HOOK(HOOK_CHIPSET_SUSPEND, kblight_suspend, HOOK_PRIO_DEFAULT);
+
+static void kblight_resume(void)
+{
+	if (lid_is_open()) {
+		kblight_enable(1);
+		kblight_set(current_percent);
+	}
+}
+DECLARE_HOOK(HOOK_CHIPSET_RESUME, kblight_resume, HOOK_PRIO_DEFAULT);
+
+static void kblight_lid_change(void)
+{
+	kblight_enable(lid_is_open());
+}
+DECLARE_HOOK(HOOK_LID_CHANGE, kblight_lid_change, HOOK_PRIO_DEFAULT);
+
+/*
+ * Console and host commands
+ */
+static int cc_kblight(int argc, char **argv)
+{
+	if (argc >= 2) {
+		char *e;
+		int i = strtoi(argv[1], &e, 0);
+		if (*e)
+			return EC_ERROR_PARAM1;
+		if (kblight_set(i))
+			return EC_ERROR_PARAM1;
+	}
+	ccprintf("Keyboard backlight: %d%%\n", kblight_get());
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(kblight, cc_kblight,
+			"percent",
+			"Get/set keyboard backlight");
+
+int hc_get_keyboard_backlight(struct host_cmd_handler_args *args)
+{
+	struct ec_response_pwm_get_keyboard_backlight *r = args->response;
+
+	r->percent = kblight_get();
+	r->enabled = 1;			/* Deprecated */
+	args->response_size = sizeof(*r);
+
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_GET_KEYBOARD_BACKLIGHT,
+		     hc_get_keyboard_backlight,
+		     EC_VER_MASK(0));
+
+int hc_set_keyboard_backlight(struct host_cmd_handler_args *args)
+{
+	const struct ec_params_pwm_set_keyboard_backlight *p = args->params;
+
+	if (kblight_set(p->percent))
+		return EC_RES_ERROR;
+	return EC_RES_SUCCESS;
+}
+DECLARE_HOST_COMMAND(EC_CMD_PWM_SET_KEYBOARD_BACKLIGHT,
+		     hc_set_keyboard_backlight,
+		     EC_VER_MASK(0));