Kirby LED driver

This is just a simple driver that provides a function to set LED color
and also a console command for testing.

BUG=chrome-os-partner:22056
TEST=Change LED color and brightness with the console command.
BRANCH=None

Change-Id: I66ece63310a0547127698d1b242a5a1c130abff6
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/167450

board/kirby/board.c

@@ -12,6 +12,8 @@
 #include "i2c.h"
 #include "keyboard_raw.h"
 #include "lid_switch.h"
+#include "pwm.h"
+#include "pwm_data.h"
 #include "registers.h"
 #include "spi.h"
 #include "task.h"
@@ -95,7 +97,7 @@ BUILD_ASSERT(ARRAY_SIZE(gpio_list) == GPIO_COUNT);
 
 /* Pins with alternate functions */
 const struct gpio_alt_func gpio_alt_funcs[] = {
-	{GPIO_C, 0x00e0, GPIO_ALT_TIM3_4, MODULE_LED_KIRBY},
+	{GPIO_C, 0x01c0, GPIO_ALT_TIM3_4, MODULE_LED_KIRBY},
 	{GPIO_A, 0x00f0, GPIO_ALT_SPI,    MODULE_SPI},
 	{GPIO_A, 0x0600, GPIO_ALT_USART,  MODULE_UART},
 	{GPIO_B, 0x00c0, GPIO_ALT_I2C,	  MODULE_I2C},
@@ -112,6 +114,17 @@ const struct battery_temperature_ranges bat_temp_ranges = {
 	.discharging_max_c    = 100,
 };
 
+/* PWM channels */
+const struct pwm_t pwm_channels[] = {
+	[PWM_CH_CHG_Y] = {STM32_TIM(3), STM32_TIM_CH(1), PWM_CONFIG_ACTIVE_LOW,
+			  GPIO_CHG_LED_Y},
+	[PWM_CH_CHG_G] = {STM32_TIM(3), STM32_TIM_CH(2), PWM_CONFIG_ACTIVE_LOW,
+			  GPIO_CHG_LED_G},
+	[PWM_CH_CHG_R] = {STM32_TIM(3), STM32_TIM_CH(3), PWM_CONFIG_ACTIVE_LOW,
+			  GPIO_CHG_LED_R},
+};
+BUILD_ASSERT(ARRAY_SIZE(pwm_channels) == PWM_CH_COUNT);
+
 /* I2C ports */
 const struct i2c_port_t i2c_ports[] = {
 	{"host", I2C_PORT_HOST, 100},

board/kirby/board.h

@@ -18,6 +18,7 @@
 #define CONFIG_I2C
 #define CONFIG_KEYBOARD_PROTOCOL_MKBP
 #define CONFIG_SPI
+#define CONFIG_PWM
 
 #ifndef __ASSEMBLER__
 
@@ -57,6 +58,17 @@ enum module_id {
 #define TIM_CLOCK_LSB 9
 #define TIM_WATCHDOG  4
 
+/* PWM signal */
+enum pwm_channel {
+	/* Y, G, R charging LEDs */
+	PWM_CH_CHG_Y = 0,
+	PWM_CH_CHG_G,
+	PWM_CH_CHG_R,
+
+	/* Number of PWM channels */
+	PWM_CH_COUNT
+};
+
 /* GPIO signal list */
 enum gpio_signal {
 	/* Inputs with interrupt handlers are first for efficiency */

common/build.mk

@@ -13,6 +13,7 @@ common-y+=gpio_common.o version.o printf.o queue.o
 common-$(BOARD_bolt)+=battery_link.o
 common-$(BOARD_daisy)+=extpower_snow.o
 common-$(BOARD_falco)+=battery_falco.o led_falco.o
+common-$(BOARD_kirby)+=led_kirby.o
 common-$(BOARD_link)+=battery_link.o
 common-$(BOARD_peppy)+=battery_peppy.o led_common.o led_peppy.o
 common-$(BOARD_slippy)+=battery_slippy.o led_slippy.o

common/led_kirby.c

@@ -0,0 +1,70 @@
+/* Copyright (c) 2013 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.
+ *
+ * Kirby LED driver.
+ */
+
+#include "common.h"
+#include "console.h"
+#include "gpio.h"
+#include "pwm.h"
+#include "util.h"
+
+void led_set_color(uint8_t red, uint8_t green, uint8_t yellow)
+{
+	if (!yellow)
+		pwm_enable(PWM_CH_CHG_Y, 0);
+	if (!green)
+		pwm_enable(PWM_CH_CHG_G, 0);
+	if (!red)
+		pwm_enable(PWM_CH_CHG_R, 0);
+
+	/* Only allow one color of LED */
+	if (yellow) {
+		pwm_enable(PWM_CH_CHG_Y, 1);
+		pwm_set_duty(PWM_CH_CHG_Y, yellow);
+	} else if (green) {
+		pwm_enable(PWM_CH_CHG_G, 1);
+		pwm_set_duty(PWM_CH_CHG_G, green);
+	} else if (red) {
+		pwm_enable(PWM_CH_CHG_R, 1);
+		pwm_set_duty(PWM_CH_CHG_R, red);
+	} else {
+		gpio_config_module(MODULE_LED_KIRBY, 0);
+		gpio_set_level(GPIO_CHG_LED_Y, 0);
+		gpio_set_level(GPIO_CHG_LED_G, 0);
+		gpio_set_level(GPIO_CHG_LED_R, 0);
+	}
+}
+
+/*****************************************************************************/
+/* Console commands */
+
+static int command_led(int argc, char **argv)
+{
+	char *e;
+	uint8_t brightness;
+
+	if (argc != 3)
+		return EC_ERROR_PARAM_COUNT;
+
+	brightness = strtoi(argv[2], &e, 0);
+	if ((e && *e) || brightness < 0 || brightness > 100)
+		return EC_ERROR_PARAM2;
+
+	if (!strcasecmp(argv[1], "r"))
+		led_set_color(brightness, 0, 0);
+	else if (!strcasecmp(argv[1], "g"))
+		led_set_color(0, brightness, 0);
+	else if (!strcasecmp(argv[1], "y"))
+		led_set_color(0, 0, brightness);
+	else
+		return EC_ERROR_PARAM1;
+
+	return EC_SUCCESS;
+}
+DECLARE_CONSOLE_COMMAND(led, command_led,
+			"<r | g | y> <brightness>",
+			"Set the color and brightness of the LED",
+			NULL);