From ccc45444557c4527b3965c707867855ec0df0ed8 Mon Sep 17 00:00:00 2001 From: Thomas Ingleby Date: Wed, 30 Apr 2014 10:30:56 +0100 Subject: [PATCH] pwm: Updated API * Greater use of maa_result_t * Added raw mode. * Updated cycle-pwm3 to use new api. Signed-off-by: Thomas Ingleby --- api/pwm.h | 104 ++++++++++++++++++++++++++++++++++++++------------ examples/cycle-pwm3.c | 2 +- src/pwm/pwm.c | 72 +++++++++++++++++++++------------- 3 files changed, 126 insertions(+), 52 deletions(-) diff --git a/api/pwm.h b/api/pwm.h index 54cce8e..9e94304 100644 --- a/api/pwm.h +++ b/api/pwm.h @@ -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 } diff --git a/examples/cycle-pwm3.c b/examples/cycle-pwm3.c index f716cf9..1ed0d4a 100644 --- a/examples/cycle-pwm3.c +++ b/examples/cycle-pwm3.c @@ -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; } diff --git a/src/pwm/pwm.c b/src/pwm/pwm.c index 9ed1528..a0bb806 100644 --- a/src/pwm/pwm.c +++ b/src/pwm/pwm.c @@ -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; } -- 2.7.4