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pwm: Updated API

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* Greater use of maa_result_t
* Added raw mode.
* Updated cycle-pwm3 to use new api.

Signed-off-by: Thomas Ingleby <thomas.c.ingleby@intel.com>
This commit is contained in:
Thomas Ingleby
2014-04-30 10:30:56 +01:00
parent 804c4a437d
commit ccc4544455
3 changed files with 126 additions and 52 deletions
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104
api/pwm.h
View File

@@ -33,24 +33,49 @@ extern "C" {
#include "maa.h"
/**
* A strucutre representing a PWM pin
*/
typedef struct {
int chipid, pin;
FILE *duty_fp;
/*@{*/
int pin; /**< the pin number, as known to the os. */
int chipid; /**< the chip id, which the pwm resides */
FILE *duty_fp; /**< File pointer to duty file */
/*@}*/
} maa_pwm_context;
maa_pwm_context* maa_pwm_init(int chipin, int pin);
/** Initialise pwm_context, uses board mapping.
*
* @param pin The PWM PIN.
*
* @return maa_pwm_context The returned initialised pwm context
*/
maa_pwm_context* maa_pwm_init(int pin);
/** Initialise pwm_context, raw mode.
*
* @param chipid The chip inwhich the PWM is under in SYSFS
* @param pin The PWM PIN.
*
* @return maa_pwm_context The returned initialised pwm context
*/
maa_pwm_context* maa_pwm_init_raw(int chipid, int pin);
/** Set the ouput duty-cycle percentage, as a float
*
* @param percentage A floating-point value representing percentage of output.
* @param pwm The PWM context to use.
* @param percentage A floating-point value representing percentage of output.
* The value should lie between 0.0f (representing on 0%) and 1.0f
* Values above or below this range will be set at either 0.0f or 1.0f.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_write(maa_pwm_context* pwm, float percentage);
maa_result_t maa_pwm_write(maa_pwm_context* pwm, float percentage);
/** Read the ouput duty-cycle percentage, as a float
*
* @return percentage A floating-point value representing percentage of output.
* @param pwm The PWM context to use.
* @return percentage A floating-point value representing percentage of output.
* The value should lie between 0.0f (representing on 0%) and 1.0f
* Values above or below this range will be set at either 0.0f or 1.0f.
*/
@@ -58,44 +83,75 @@ float maa_pwm_read(maa_pwm_context* pwm);
/** Set the PWM period as seconds represented in a float
*
* @param seconds Peroid represented as a float in seconds.
* @param pwm The PWM context to use.
* @param seconds Peroid represented as a float in seconds.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_period(maa_pwm_context* pwm, float seconds);
maa_result_t maa_pwm_period(maa_pwm_context* pwm, float seconds);
/** Set period. milli-oseconds.
* @param ms milli-seconds for period.
*
* @param pwm The PWM context to use.
* @param ms milli-seconds for period.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_period_ms(maa_pwm_context* pwm, int ms);
maa_result_t maa_pwm_period_ms(maa_pwm_context* pwm, int ms);
/** Set period. microseconds
* @param ns microseconds as period.
*
* @param pwm The PWM context to use.
* @param ns microseconds as period.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_period_us(maa_pwm_context* pwm, int us);
maa_result_t maa_pwm_period_us(maa_pwm_context* pwm, int us);
/** Set pulsewidth, As represnted by seconds in a (float).
* @param seconds The duration of a pulse
*
* @param pwm The PWM context to use.
* @param seconds The duration of a pulse
*
* @return maa_result_t the maa result.
*/
void maa_pwm_pulsewidth(maa_pwm_context* pwm, float seconds);
maa_result_t maa_pwm_pulsewidth(maa_pwm_context* pwm, float seconds);
/** Set pulsewidth. Milliseconds
* @param ms milliseconds for pulsewidth.
/** Set pulsewidth. Milliseconds
*
* @param pwm The PWM context to use.
* @param ms milliseconds for pulsewidth.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_pulsewidth_ms(maa_pwm_context* pwm, int ms);
maa_result_t maa_pwm_pulsewidth_ms(maa_pwm_context* pwm, int ms);
/** Set pulsewidth, microseconds.
* @param us microseconds for pulsewidth.
/** Set pulsewidth, microseconds.
*
* @param pwm The PWM context to use.
* @param us microseconds for pulsewidth.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_pulsewidth_us(maa_pwm_context* pwm, int us);
maa_result_t maa_pwm_pulsewidth_us(maa_pwm_context* pwm, int us);
/** Set the enable status of the PWM pin. None zero will assume on with output being driven.
* and 0 will disable the output.
* @param enable enable status of pin
*
* @param pwm The PWM context to use.
* @param enable enable status of pin
*
* @return maa_result_t the maa result.
*/
void maa_pwm_enable(maa_pwm_context* pwm, int enable);
maa_result_t maa_pwm_enable(maa_pwm_context* pwm, int enable);
/** Close and unexport the PWM pin.
/** Close and unexport the PWM pin.
*
* @param pwm The PWM context to use.
*
* @return maa_result_t the maa result.
*/
void maa_pwm_close(maa_pwm_context* pwm);
maa_result_t maa_pwm_close(maa_pwm_context* pwm);
#ifdef __cplusplus
}

2
examples/cycle-pwm3.c
View File

@@ -30,7 +30,7 @@ int
main ()
{
maa_pwm_context* pwm;
pwm = maa_pwm_init(0, 3);
pwm = maa_pwm_init(3);
if (pwm == NULL) {
return 1;
}

72
src/pwm/pwm.c
View File

@@ -38,7 +38,7 @@ maa_pwm_setup_duty_fp(maa_pwm_context* dev)
return 0;
}
static void
static maa_result_t
maa_pwm_write_period(maa_pwm_context* dev, int period)
{
FILE *period_f;
@@ -47,12 +47,16 @@ maa_pwm_write_period(maa_pwm_context* dev, int period)
if ((period_f = fopen(bu, "r+b")) == NULL) {
fprintf(stderr, "Failed to open period for writing!\n");
return MAA_ERROR_INVALID_RESOURCE;
}
fprintf(period_f, "%d", period);
fclose(period_f);
if (ferror(period_f) != 0)
return MAA_ERROR_INVALID_RESOURCE;
return MAA_SUCCESS;
}
static void
static maa_result_t
maa_pwm_write_duty(maa_pwm_context* dev, int duty)
{
if (dev->duty_fp == NULL) {
@@ -61,6 +65,9 @@ maa_pwm_write_duty(maa_pwm_context* dev, int duty)
fprintf(dev->duty_fp, "%d", duty);
rewind(dev->duty_fp);
fflush(dev->duty_fp);
if (ferror(dev->duty_fp) != 0)
return MAA_ERROR_INVALID_RESOURCE;
return MAA_SUCCESS;
}
static int
@@ -93,7 +100,13 @@ maa_pwm_get_duty(maa_pwm_context* dev)
}
maa_pwm_context*
maa_pwm_init(int chipin, int pin)
maa_pwm_init(int pin) {
//TODO
return maa_pwm_init_raw(0, pin);
}
maa_pwm_context*
maa_pwm_init_raw(int chipin, int pin)
{
maa_pwm_context* dev = (maa_pwm_context*) malloc(sizeof(maa_pwm_context));
if (dev == NULL)
@@ -118,10 +131,10 @@ maa_pwm_init(int chipin, int pin)
return dev;
}
void
maa_result_t
maa_pwm_write(maa_pwm_context* dev, float percentage)
{
maa_pwm_write_duty(dev, percentage * maa_pwm_get_period(dev));
return maa_pwm_write_duty(dev, percentage * maa_pwm_get_period(dev));
}
float
@@ -131,43 +144,43 @@ maa_pwm_read(maa_pwm_context* dev)
return output;
}
void
maa_result_t
maa_pwm_period(maa_pwm_context* dev, float seconds)
{
maa_pwm_period_ms(dev, seconds*1000);
return maa_pwm_period_ms(dev, seconds*1000);
}
void
maa_result_t
maa_pwm_period_ms(maa_pwm_context* dev, int ms)
{
maa_pwm_period_us(dev, ms*1000);
return maa_pwm_period_us(dev, ms*1000);
}
void
maa_result_t
maa_pwm_period_us(maa_pwm_context* dev, int us)
{
maa_pwm_write_period(dev, us*1000);
return maa_pwm_write_period(dev, us*1000);
}
void
maa_result_t
maa_pwm_pulsewidth(maa_pwm_context* dev, float seconds)
{
maa_pwm_pulsewidth_ms(dev, seconds*1000);
return maa_pwm_pulsewidth_ms(dev, seconds*1000);
}
void
maa_result_t
maa_pwm_pulsewidth_ms(maa_pwm_context* dev, int ms)
{
maa_pwm_pulsewidth_us(dev, ms*1000);
return maa_pwm_pulsewidth_us(dev, ms*1000);
}
void
maa_result_t
maa_pwm_pulsewidth_us(maa_pwm_context* dev, int us)
{
maa_pwm_write_duty(dev, us*1000);
return maa_pwm_write_duty(dev, us*1000);
}
void
maa_result_t
maa_pwm_enable(maa_pwm_context* dev, int enable)
{
int status;
@@ -181,15 +194,17 @@ maa_pwm_enable(maa_pwm_context* dev, int enable)
sprintf(bu, "/sys/class/pwm/pwmchip%d/pwm%d/enable", dev->chipid, dev->pin);
if ((enable_f = fopen(bu, "w")) == NULL) {
fprintf(stderr, "Failed to open export for writing!\n");
} else {
fprintf(enable_f, "%d", status);
fclose(enable_f);
fprintf(stderr, "Failed to open enable for writing!\n");
return MAA_ERROR_INVALID_RESOURCE;
}
//Do Something
fprintf(enable_f, "%d", status);
fclose(enable_f);
if (ferror(enable_f) != 0)
return MAA_ERROR_INVALID_RESOURCE;
return MAA_SUCCESS;
}
void
maa_result_t
maa_pwm_close(maa_pwm_context* dev)
{
maa_pwm_enable(dev, 0);
@@ -199,9 +214,12 @@ maa_pwm_close(maa_pwm_context* dev)
if ((unexport_f = fopen(buffer, "w")) == NULL) {
fprintf(stderr, "Failed to open unexport for writing!\n");
} else {
fprintf(unexport_f, "%d", dev->pin);
fclose(unexport_f);
return MAA_ERROR_INVALID_RESOURCE;
}
fprintf(unexport_f, "%d", dev->pin);
fclose(unexport_f);
free(dev);
if (ferror(unexport_f) != 0)
return MAA_ERROR_INVALID_RESOURCE;
return MAA_SUCCESS;
}