/******************************************************************************
* Copyright 2013-2014 Espressif Systems (Wuxi)
*
* FileName: pwm.c
*
* Description: pwm driver
*
* Modification history:
* 2014/5/1, v1.0 create this file.
*******************************************************************************/
#include "platform.h"
#include "ets_sys.h"
#include "os_type.h"
#include "osapi.h"
#include "gpio.h"
#include "hw_timer.h"
#include "user_interface.h"
#include "driver/pwm.h"
// #define PWM_DBG os_printf
#define PWM_DBG
// Enabling the next line will cause the interrupt handler to toggle
// this output pin during processing so that the timing is obvious
//
// #define PWM_DBG_PIN 13 // GPIO7
#ifdef PWM_DBG_PIN
#define PWM_DBG_PIN_HIGH() GPIO_REG_WRITE(GPIO_OUT_W1TS_ADDRESS, 1 << PWM_DBG_PIN)
#define PWM_DBG_PIN_LOW() GPIO_REG_WRITE(GPIO_OUT_W1TC_ADDRESS, 1 << PWM_DBG_PIN)
#else
#define PWM_DBG_PIN_HIGH()
#define PWM_DBG_PIN_LOW()
#endif
LOCAL struct pwm_single_param pwm_single_toggle[2][PWM_CHANNEL + 1];
LOCAL struct pwm_single_param *pwm_single;
LOCAL struct pwm_param pwm;
// LOCAL uint8 pwm_out_io_num[PWM_CHANNEL] = {PWM_0_OUT_IO_NUM, PWM_1_OUT_IO_NUM, PWM_2_OUT_IO_NUM};
LOCAL int8 pwm_out_io_num[PWM_CHANNEL] = {-1, -1, -1, -1, -1, -1};
LOCAL uint8 pwm_channel_toggle[2];
LOCAL uint8 *pwm_channel;
// Toggle flips between 1 and 0 when we make updates so that the interrupt code
// cn switch cleanly between the two states. The cinterrupt handler uses either
// the pwm_single_toggle[0] or pwm_single_toggle[1]
// pwm_toggle indicates which state should be used on the *next* timer interrupt
// freq boundary.
LOCAL uint8 pwm_toggle = 1;
LOCAL volatile uint8 pwm_current_toggle = 1;
LOCAL uint8 pwm_timer_down = 1;
LOCAL uint8 pwm_current_channel = 0;
LOCAL uint16 pwm_gpio = 0;
LOCAL uint8 pwm_channel_num = 0;
LOCAL void ICACHE_RAM_ATTR pwm_tim1_intr_handler(os_param_t p);
#define TIMER_OWNER ((os_param_t) 'P')
LOCAL void ICACHE_FLASH_ATTR
pwm_insert_sort(struct pwm_single_param pwm[], uint8 n)
{
uint8 i;
for (i = 1; i < n; i++) {
if (pwm[i].h_time < pwm[i - 1].h_time) {
int8 j = i - 1;
struct pwm_single_param tmp;
os_memcpy(&tmp, &pwm[i], sizeof(struct pwm_single_param));
while (tmp.h_time < pwm[j].h_time) {
os_memcpy(&pwm[j + 1], &pwm[j], sizeof(struct pwm_single_param));
j--;
if (j < 0) {
break;
}
}
os_memcpy(&pwm[j + 1], &tmp, sizeof(struct pwm_single_param));
}
}
}
// Returns FALSE if we cannot start
bool ICACHE_FLASH_ATTR
pwm_start(void)
{
uint8 i, j;
PWM_DBG("--Function pwm_start() is called\n");
PWM_DBG("pwm_gpio:%x,pwm_channel_num:%d\n",pwm_gpio,pwm_channel_num);
PWM_DBG("pwm_out_io_num[0]:%d,[1]:%d,[2]:%d\n",pwm_out_io_num[0],pwm_out_io_num[1],pwm_out_io_num[2]);
PWM_DBG("pwm.period:%d,pwm.duty[0]:%d,[1]:%d,[2]:%d\n",pwm.period,pwm.duty[0],pwm.duty[1],pwm.duty[2]);
// First we need to make sure that the interrupt handler is running
// out of the same set of params as we expect
while (!pwm_timer_down && pwm_toggle != pwm_current_toggle) {
os_delay_us(100);
}
if (pwm_timer_down) {
pwm_toggle = pwm_current_toggle;
}
uint8_t new_toggle = pwm_toggle ^ 0x01;
struct pwm_single_param *local_single = pwm_single_toggle[new_toggle];
uint8 *local_channel = &pwm_channel_toggle[new_toggle];
// step 1: init PWM_CHANNEL+1 channels param
for (i = 0; i < pwm_channel_num; i++) {
uint32 us = pwm.period * pwm.duty[i] / PWM_DEPTH;
local_single[i].h_time = US_TO_RTC_TIMER_TICKS(us);
PWM_DBG("i:%d us:%d ht:%d\n",i,us,local_single[i].h_time);
local_single[i].gpio_set = 0;
local_single[i].gpio_clear = 1 << pin_num[pwm_out_io_num[i]];
}
local_single[pwm_channel_num].h_time = US_TO_RTC_TIMER_TICKS(pwm.period);
local_single[pwm_channel_num].gpio_set = pwm_gpio;
local_single[pwm_channel_num].gpio_clear = 0;
PWM_DBG("i:%d period:%d ht:%d\n",pwm_channel_num,pwm.period,local_single[pwm_channel_num].h_time);
// step 2: sort, small to big
pwm_insert_sort(local_single, pwm_channel_num + 1);
*local_channel = pwm_channel_num + 1;
PWM_DBG("1channel:%d,single[0]:%d,[1]:%d,[2]:%d,[3]:%d\n",*local_channel,local_single[0].h_time,local_single[1].h_time,local_single[2].h_time,local_single[3].h_time);
// step 3: combine same duty channels (or nearly the same duty). If there is
// under 2 us between pwm outputs, then treat them as the same.
for (i = pwm_channel_num; i > 0; i--) {
if (local_single[i].h_time <= local_single[i - 1].h_time + US_TO_RTC_TIMER_TICKS(2)) {
local_single[i - 1].gpio_set |= local_single[i].gpio_set;
local_single[i - 1].gpio_clear |= local_single[i].gpio_clear;
for (j = i + 1; j < *local_channel; j++) {
os_memcpy(&local_single[j - 1], &local_single[j], sizeof(struct pwm_single_param));
}
(*local_channel)--;
}
}
PWM_DBG("2channel:%d,single[0]:%d,[1]:%d,[2]:%d,[3]:%d\n",*local_channel,local_single[0].h_time,local_single[1].h_time,local_single[2].h_time,local_single[3].h_time);
// step 4: cacl delt time
for (i = *local_channel - 1; i > 0; i--) {
local_single[i].h_time -= local_single[i - 1].h_time;
}
// step 5: last channel needs to clean
local_single[*local_channel-1].gpio_clear = 0;
// step 6: if first channel duty is 0, remove it
if (local_single[0].h_time == 0) {
local_single[*local_channel - 1].gpio_set &= ~local_single[0].gpio_clear;
local_single[*local_channel - 1].gpio_clear |= local_single[0].gpio_clear;
for (i = 1; i < *local_channel; i++) {
os_memcpy(&local_single[i - 1], &local_single[i], sizeof(struct pwm_single_param));
}
(*local_channel)--;
}
// Make the new ones active
pwm_toggle = new_toggle;
// if timer is down, need to set gpio and start timer
if (pwm_timer_down == 1) {
pwm_channel = local_channel;
pwm_single = local_single;
pwm_current_toggle = pwm_toggle;
// start
gpio_output_set(local_single[0].gpio_set, local_single[0].gpio_clear, pwm_gpio, 0);
// yeah, if all channels' duty is 0 or 255, don't need to start timer, otherwise start...
if (*local_channel != 1) {
PWM_DBG("Need to setup timer\n");
if (!platform_hw_timer_init(TIMER_OWNER, FRC1_SOURCE, FALSE)) {
return FALSE;
}
pwm_timer_down = 0;
platform_hw_timer_set_func(TIMER_OWNER, pwm_tim1_intr_handler, 0);
platform_hw_timer_arm_ticks(TIMER_OWNER, local_single[0].h_time);
} else {
PWM_DBG("Timer left idle\n");
platform_hw_timer_close(TIMER_OWNER);
}
} else {
// ensure that all outputs are outputs
gpio_output_set(0, 0, pwm_gpio, 0);
}
#ifdef PWM_DBG_PIN
// Enable as output
gpio_output_set(0, 0, 1 << PWM_DBG_PIN, 0);
#endif
PWM_DBG("3channel:%d,single[0]:%d,[1]:%d,[2]:%d,[3]:%d\n",*local_channel,local_single[0].h_time,local_single[1].h_time,local_single[2].h_time,local_single[3].h_time);
return TRUE;
}
/******************************************************************************
* FunctionName : pwm_set_duty
* Description : set each channel's duty params
* Parameters : uint8 duty : 0 ~ PWM_DEPTH
* uint8 channel : channel index
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
pwm_set_duty(uint16 duty, uint8 channel)
{
uint8 i;
for(i=0;i<pwm_channel_num;i++){
if(pwm_out_io_num[i] == channel){
channel = i;
break;
}
}
if(i==pwm_channel_num) // non found
return;
if (duty < 1) {
pwm.duty[channel] = 0;
} else if (duty >= PWM_DEPTH) {
pwm.duty[channel] = PWM_DEPTH;
} else {
pwm.duty[channel] = duty;
}
}
/******************************************************************************
* FunctionName : pwm_set_freq
* Description : set pwm frequency
* Parameters : uint16 freq : 100hz typically
* Returns : NONE
*******************************************************************************/
void ICACHE_FLASH_ATTR
pwm_set_freq(uint16 freq, uint8 channel)
{
if (freq > PWM_FREQ_MAX) {
pwm.freq = PWM_FREQ_MAX;
} else if (freq < 1) {
pwm.freq = 1;
} else {
pwm.freq = freq;
}
pwm.period = PWM_1S / pwm.freq;
}
/******************************************************************************
* FunctionName : pwm_set_freq_duty
* Description : set pwm frequency and each channel's duty
* Parameters : uint16 freq : 100hz typically
* uint16 *duty : each channel's duty
* Returns : NONE
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
pwm_set_freq_duty(uint16 freq, uint16 *duty)
{
uint8 i;
pwm_set_freq(freq, 0);
for (i = 0; i < PWM_CHANNEL; i++) {
// pwm_set_duty(duty[i], i);
if(pwm_out_io_num[i] != -1)
pwm_set_duty(duty[i], pwm_out_io_num[i]);
}
}
/******************************************************************************
* FunctionName : pwm_get_duty
* Description : get duty of each channel
* Parameters : uint8 channel : channel index
* Returns : NONE
*******************************************************************************/
uint16 ICACHE_FLASH_ATTR
pwm_get_duty(uint8 channel)
{
uint8 i;
for(i=0;i<pwm_channel_num;i++){
if(pwm_out_io_num[i] == channel){
channel = i;
break;
}
}
if(i==pwm_channel_num) // non found
return 0;
return pwm.duty[channel];
}
/******************************************************************************
* FunctionName : pwm_get_freq
* Description : get pwm frequency
* Parameters : NONE
* Returns : uint16 : pwm frequency
*******************************************************************************/
uint16 ICACHE_FLASH_ATTR
pwm_get_freq(uint8 channel)
{
return pwm.freq;
}
/******************************************************************************
* FunctionName : pwm_period_timer
* Description : pwm period timer function, output high level,
* start each channel's high level timer
* Parameters : NONE
* Returns : NONE
*******************************************************************************/
LOCAL void ICACHE_RAM_ATTR
pwm_tim1_intr_handler(os_param_t p)
{
(void)p;
PWM_DBG_PIN_HIGH();
int offset = 0;
while (1) {
if (pwm_current_channel >= (*pwm_channel - 1)) {
pwm_single = pwm_single_toggle[pwm_toggle];
pwm_channel = &pwm_channel_toggle[pwm_toggle];
pwm_current_toggle = pwm_toggle;
gpio_output_set(pwm_single[*pwm_channel - 1].gpio_set,
pwm_single[*pwm_channel - 1].gpio_clear,
0,
0);
pwm_current_channel = 0;
if (*pwm_channel == 1) {
pwm_timer_down = 1;
break;
}
} else {
gpio_output_set(pwm_single[pwm_current_channel].gpio_set,
pwm_single[pwm_current_channel].gpio_clear,
0, 0);
pwm_current_channel++;
}
int next_time = pwm_single[pwm_current_channel].h_time;
// Delay now holds the time (in ticks) since when the last timer expiry was
PWM_DBG_PIN_LOW();
int delay = platform_hw_timer_get_delay_ticks(TIMER_OWNER) + 4 - offset;
offset += next_time;
next_time = next_time - delay;
if (next_time > US_TO_RTC_TIMER_TICKS(4)) {
PWM_DBG_PIN_HIGH();
platform_hw_timer_arm_ticks(TIMER_OWNER, next_time);
break;
}
PWM_DBG_PIN_HIGH();
}
PWM_DBG_PIN_LOW();
}
/******************************************************************************
* FunctionName : pwm_init
* Description : pwm gpio, params and timer initialization
* Parameters : uint16 freq : pwm freq param
* uint16 *duty : each channel's duty
* Returns : void
*******************************************************************************/
void ICACHE_FLASH_ATTR
pwm_init(uint16 freq, uint16 *duty)
{
uint8 i;
// PIN_FUNC_SELECT(PWM_0_OUT_IO_MUX, PWM_0_OUT_IO_FUNC);
// PIN_FUNC_SELECT(PWM_1_OUT_IO_MUX, PWM_1_OUT_IO_FUNC);
// PIN_FUNC_SELECT(PWM_2_OUT_IO_MUX, PWM_2_OUT_IO_FUNC);
// GPIO_OUTPUT_SET(GPIO_ID_PIN(PWM_0_OUT_IO_NUM), 0);
// GPIO_OUTPUT_SET(GPIO_ID_PIN(PWM_1_OUT_IO_NUM), 0);
// GPIO_OUTPUT_SET(GPIO_ID_PIN(PWM_2_OUT_IO_NUM), 0);
for (i = 0; i < PWM_CHANNEL; i++) {
// pwm_gpio |= (1 << pwm_out_io_num[i]);
pwm_gpio = 0;
pwm.duty[i] = 0;
}
pwm_set_freq(500, 0);
// pwm_set_freq_duty(freq, duty);
pwm_start();
PWM_DBG("pwm_init returning\n");
}
bool ICACHE_FLASH_ATTR
pwm_add(uint8 channel){
PWM_DBG("--Function pwm_add() is called. channel:%d\n", channel);
PWM_DBG("pwm_gpio:%x,pwm_channel_num:%d\n",pwm_gpio,pwm_channel_num);
PWM_DBG("pwm_out_io_num[0]:%d,[1]:%d,[2]:%d\n",pwm_out_io_num[0],pwm_out_io_num[1],pwm_out_io_num[2]);
PWM_DBG("pwm.duty[0]:%d,[1]:%d,[2]:%d\n",pwm.duty[0],pwm.duty[1],pwm.duty[2]);
uint8 i;
for(i=0;i<PWM_CHANNEL;i++){
if(pwm_out_io_num[i]==channel) // already exist
return true;
if(pwm_out_io_num[i] == -1){ // empty exist
pwm_out_io_num[i] = channel;
pwm.duty[i] = 0;
pwm_gpio |= (1 << pin_num[channel]);
PIN_FUNC_SELECT(pin_mux[channel], pin_func[channel]);
GPIO_REG_WRITE(GPIO_PIN_ADDR(GPIO_ID_PIN(pin_num[channel])), GPIO_REG_READ(GPIO_PIN_ADDR(GPIO_ID_PIN(pin_num[channel]))) & (~ GPIO_PIN_PAD_DRIVER_SET(GPIO_PAD_DRIVER_ENABLE))); //disable open drain;
pwm_channel_num++;
return true;
}
}
return false;
}
bool ICACHE_FLASH_ATTR
pwm_delete(uint8 channel){
PWM_DBG("--Function pwm_delete() is called. channel:%d\n", channel);
PWM_DBG("pwm_gpio:%x,pwm_channel_num:%d\n",pwm_gpio,pwm_channel_num);
PWM_DBG("pwm_out_io_num[0]:%d,[1]:%d,[2]:%d\n",pwm_out_io_num[0],pwm_out_io_num[1],pwm_out_io_num[2]);
PWM_DBG("pwm.duty[0]:%d,[1]:%d,[2]:%d\n",pwm.duty[0],pwm.duty[1],pwm.duty[2]);
uint8 i,j;
for(i=0;i<pwm_channel_num;i++){
if(pwm_out_io_num[i]==channel){ // exist
pwm_out_io_num[i] = -1;
pwm_gpio &= ~(1 << pin_num[channel]); //clear the bit
for(j=i;j<pwm_channel_num-1;j++){
pwm_out_io_num[j] = pwm_out_io_num[j+1];
pwm.duty[j] = pwm.duty[j+1];
}
pwm_out_io_num[pwm_channel_num-1] = -1;
pwm.duty[pwm_channel_num-1] = 0;
pwm_channel_num--;
return true;
}
}
// non found
return true;
}
bool ICACHE_FLASH_ATTR
pwm_exist(uint8 channel){
PWM_DBG("--Function pwm_exist() is called. channel:%d\n", channel);
PWM_DBG("pwm_gpio:%x,pwm_channel_num:%d\n",pwm_gpio,pwm_channel_num);
PWM_DBG("pwm_out_io_num[0]:%d,[1]:%d,[2]:%d\n",pwm_out_io_num[0],pwm_out_io_num[1],pwm_out_io_num[2]);
PWM_DBG("pwm.duty[0]:%d,[1]:%d,[2]:%d\n",pwm.duty[0],pwm.duty[1],pwm.duty[2]);
uint8 i;
for(i=0;i<PWM_CHANNEL;i++){
if(pwm_out_io_num[i]==channel) // exist
return true;
}
return false;
}