mtk平台pwm配置说明

摘自mt6755平台Android L cust_led.c

#include <cust_leds.h>#include <cust_leds_def.h>#include <mach/mt_pwm.h>#include <linux/kernel.h>#include <mach/upmu_common_sw.h>#include <mach/upmu_hw.h>//extern int mtkfb_set_backlight_level(unsigned int level);//extern int mtkfb_set_backlight_pwm(int div);extern int disp_bls_set_backlight(unsigned int level);// Only support 64 levels of backlight (when lcd-backlight = MT65XX_LED_MODE_PWM)#define BACKLIGHT_LEVEL_PWM_64_FIFO_MODE_SUPPORT 64 // Support 256 levels of backlight (when lcd-backlight = MT65XX_LED_MODE_PWM)#define BACKLIGHT_LEVEL_PWM_256_SUPPORT 256 // Configure the support type "BACKLIGHT_LEVEL_PWM_256_SUPPORT" or "BACKLIGHT_LEVEL_PWM_64_FIFO_MODE_SUPPORT" !!#define BACKLIGHT_LEVEL_PWM_MODE_CONFIG BACKLIGHT_LEVEL_PWM_256_SUPPORTunsigned int Cust_GetBacklightLevelSupport_byPWM(void){return BACKLIGHT_LEVEL_PWM_MODE_CONFIG;}unsigned int brightness_mapping(unsigned int level){    unsigned int mapped_level;        mapped_level = level;       return mapped_level;}/* * To explain How to set these para for cust_led_list[] of led/backlight * "name" para: led or backlight * "mode" para:which mode for led/backlight *such as: *MT65XX_LED_MODE_NONE, *MT65XX_LED_MODE_PWM, *MT65XX_LED_MODE_GPIO, *MT65XX_LED_MODE_PMIC, *MT65XX_LED_MODE_CUST_LCM, *MT65XX_LED_MODE_CUST_BLS_PWM * *"data" para: control methord for led/backlight *   such as: *MT65XX_LED_PMIC_LCD_ISINK=0, *MT65XX_LED_PMIC_NLED_ISINK0, *MT65XX_LED_PMIC_NLED_ISINK1, *MT65XX_LED_PMIC_NLED_ISINK2, *MT65XX_LED_PMIC_NLED_ISINK3 *  *"PWM_config" para:PWM(AP side Or BLS module), by default setting{0,0,0,0,0} Or {0} *struct PWM_config {  *  int clock_source; *  int div;  *  int low_duration; *  int High_duration; *  BOOL pmic_pad;//AP side PWM pin in PMIC chip (only 89 needs confirm); 1:yes 0:no(default) *}; *------------------------------------------------------------------------------------------- *   for AP PWM setting as follow: *1. PWM config data *  clock_source: clock source frequency, can be 0/1 *  div: clock division, can be any value within 0~7 (i.e. 1/2^(div) = /1, /2, /4, /8, /16, /32, /64, /128) *  low_duration: only for BACKLIGHT_LEVEL_PWM_64_FIFO_MODE_SUPPORT *  High_duration: only for BACKLIGHT_LEVEL_PWM_64_FIFO_MODE_SUPPORT * *2. PWM freq. * If BACKLIGHT_LEVEL_PWM_MODE_CONFIG = BACKLIGHT_LEVEL_PWM_256_SUPPORT, * PWM freq. = clock source / 2^(div) / 256   * * If BACKLIGHT_LEVEL_PWM_MODE_CONFIG = BACKLIGHT_LEVEL_PWM_64_FIFO_MODE_SUPPORT, * PWM freq. = clock source / 2^(div) / [(High_duration+1)(Level')+(low_duration+1)(64 - Level')] *           = clock source / 2^(div) / [(High_duration+1)*64]     (when low_duration = High_duration) *Clock source:  * 0: block clock/1625 = 26M/1625 = 16K (MT6571) * 1: block clock = 26M (MT6571) *Div: 0~7 * *For example, in MT6571, PWM_config = {1,1,0,0,0}  * ==> PWM freq. = 26M/2^1/256  =50.78 KHz ( when BACKLIGHT_LEVEL_PWM_256_SUPPORT ) * ==> PWM freq. = 26M/2^1/(0+1)*64 = 203.13 KHz ( when BACKLIGHT_LEVEL_PWM_64_FIFO_MODE_SUPPORT ) *------------------------------------------------------------------------------------------- *   for BLS PWM setting as follow: *1. PWM config data * clock_source: clock source frequency, can be 0/1/2/3 * div: clock division, can be any value within 0~1023 * low_duration: non-use * High_duration: non-use * pmic_pad: non-use * *2. PWM freq.= clock source / (div + 1) /1024 *Clock source:  * 0: 26 MHz * 1: 104 MHz * 2: 124.8 MHz * 3: 156 MHz *Div: 0~1023 * *By default, clock_source = 0 and div = 0 => PWM freq. = 26 KHz  *------------------------------------------------------------------------------------------- */static struct cust_mt65xx_led cust_led_list[MT65XX_LED_TYPE_TOTAL] = {{"red",               MT65XX_LED_MODE_NONE, -1,{0}},{"green",             MT65XX_LED_MODE_NONE, -1,{0}},{"blue",              MT65XX_LED_MODE_NONE, -1,{0}},{"jogball-backlight", MT65XX_LED_MODE_NONE, -1,{0}},{"keyboard-backlight",MT65XX_LED_MODE_NONE, -1,{0}},{"button-backlight",  MT65XX_LED_MODE_NONE, -1,{0}},{"lcd-backlight",     MT65XX_LED_MODE_CUST_BLS_PWM, (long)disp_bls_set_backlight, {3, 0, 0, 0, 0} },};struct cust_mt65xx_led *get_cust_led_list(void){return cust_led_list;}