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led: Add on board LED support

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This patch adds support for using on board LED through sysfs.
Commonly available LED parameters are supported.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>
This commit is contained in:
Manivannan Sadhasivam
2017-08-25 18:01:19 +05:30
committed by Brendan Le Foll
parent e7b51f3b66
commit e1382ad845
8 changed files with 653 additions and 1 deletions
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3
src/CMakeLists.txt
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@@ -28,6 +28,7 @@ set (mraa_LIB_SRCS_NOAUTO
${PROJECT_SOURCE_DIR}/src/spi/spi.c
${PROJECT_SOURCE_DIR}/src/aio/aio.c
${PROJECT_SOURCE_DIR}/src/uart/uart.c
${PROJECT_SOURCE_DIR}/src/led/led.c
${mraa_LIB_SRCS_NOAUTO}
)
@@ -236,7 +237,7 @@ mraa_create_install_pkgconfig (mraa.pc ${LIB_INSTALL_DIR}/pkgconfig)
if (DOXYGEN_FOUND)
set (CMAKE_SWIG_FLAGS -DDOXYGEN=${DOXYGEN_FOUND})
set (DOCCLASSES aio gpio i2c pwm spi uart)
set (DOCCLASSES aio gpio i2c pwm spi uart led)
# CPP class headers
foreach (_file ${DOCCLASSES})
add_custom_command (OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${_file}_class_doc.i

380
src/led/led.c Normal file
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@@ -0,0 +1,380 @@
/*
* Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
* Copyright (c) 2017 Linaro Ltd.
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include "led.h"
#include "mraa_internal.h"
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdlib.h>
#include <string.h>
#include <sys/errno.h>
#include <sys/stat.h>
#include <unistd.h>
#define SYSFS_CLASS_LED "/sys/class/leds"
#define MAX_SIZE 64
static mraa_result_t
mraa_led_get_trigfd(mraa_led_context dev)
{
char buf[MAX_SIZE];
snprintf(buf, MAX_SIZE, "%s/%s", dev->led_path, "trigger");
dev->trig_fd = open(buf, O_RDWR);
if (dev->trig_fd == -1) {
syslog(LOG_ERR, "led: trigger: Failed to open 'trigger': %s", strerror(errno));
return MRAA_ERROR_INVALID_RESOURCE;
}
return MRAA_SUCCESS;
}
static mraa_result_t
mraa_led_get_brightfd(mraa_led_context dev)
{
char buf[MAX_SIZE];
snprintf(buf, MAX_SIZE, "%s/%s", dev->led_path, "brightness");
dev->bright_fd = open(buf, O_RDWR);
if (dev->bright_fd == -1) {
syslog(LOG_ERR, "led: brightness: Failed to open 'brightness': %s", strerror(errno));
return MRAA_ERROR_INVALID_RESOURCE;
}
return MRAA_SUCCESS;
}
static mraa_result_t
mraa_led_get_maxbrightfd(mraa_led_context dev)
{
char buf[MAX_SIZE];
snprintf(buf, MAX_SIZE, "%s/%s", dev->led_path, "max_brightness");
dev->max_bright_fd = open(buf, O_RDONLY);
if (dev->max_bright_fd == -1) {
syslog(LOG_ERR, "led: max_brightness: Failed to open 'max_brightness': %s", strerror(errno));
return MRAA_ERROR_INVALID_RESOURCE;
}
return MRAA_SUCCESS;
}
static mraa_led_context
mraa_led_init_internal(const char* led)
{
DIR* dir;
struct dirent* entry;
int cnt = 0;
mraa_led_context dev = (mraa_led_context) calloc(1, sizeof(struct _led));
if (dev == NULL) {
syslog(LOG_CRIT, "led: init: Failed to allocate memory for context");
return NULL;
}
dev->led_name = NULL;
dev->trig_fd = -1;
dev->bright_fd = -1;
dev->max_bright_fd = -1;
if ((dir = opendir(SYSFS_CLASS_LED)) != NULL) {
/* get the led name from sysfs path */
while ((entry = readdir(dir)) != NULL) {
if (strstr((const char*) entry->d_name, led)) {
dev->led_name = (char*) entry->d_name;
}
cnt++;
}
}
dev->count = cnt;
if (dev->led_name == NULL) {
syslog(LOG_CRIT, "led: init: unknown device specified");
closedir(dir);
free(dev);
return NULL;
}
closedir(dir);
return dev;
}
mraa_led_context
mraa_led_init(const char* led)
{
mraa_led_context dev = NULL;
char directory[MAX_SIZE];
struct stat dir;
if (plat == NULL) {
syslog(LOG_ERR, "led: init: platform not initialised");
return NULL;
}
if (led == NULL) {
syslog(LOG_ERR, "led: init: invalid device specified");
return NULL;
}
dev = mraa_led_init_internal(led);
if (dev == NULL) {
return NULL;
}
snprintf(directory, MAX_SIZE, "%s/%s", SYSFS_CLASS_LED, dev->led_name);
if (stat(directory, &dir) == 0 && S_ISDIR(dir.st_mode)) {
syslog(LOG_NOTICE, "led: init: current user don't have access rights for using LED %s", dev->led_name);
}
strncpy(dev->led_path, (const char*) directory, sizeof(directory));
return dev;
}
mraa_result_t
mraa_led_set_brightness(mraa_led_context dev, int value)
{
char buf[MAX_SIZE];
int length;
if (dev == NULL) {
syslog(LOG_ERR, "led: set_brightness: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (dev->trig_fd != -1) {
close(dev->trig_fd);
dev->trig_fd = -1;
}
if (dev->max_bright_fd != -1) {
close(dev->max_bright_fd);
dev->max_bright_fd = -1;
}
if (dev->bright_fd == -1) {
if (mraa_led_get_brightfd(dev) != MRAA_SUCCESS) {
return MRAA_ERROR_INVALID_RESOURCE;
}
}
if (lseek(dev->bright_fd, 0, SEEK_SET) == -1) {
syslog(LOG_ERR, "led: set_brightness: Failed to lseek 'brightness': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
length = snprintf(buf, sizeof(buf), "%d", value);
if (write(dev->bright_fd, buf, length * sizeof(char)) == -1) {
syslog(LOG_ERR, "led: set_brightness: Failed to write 'brightness': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
int
mraa_led_read_brightness(mraa_led_context dev)
{
char buf[3];
if (dev == NULL) {
syslog(LOG_ERR, "led: read_brightness: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (dev->trig_fd != -1) {
close(dev->trig_fd);
dev->trig_fd = -1;
}
if (dev->max_bright_fd != -1) {
close(dev->max_bright_fd);
dev->max_bright_fd = -1;
}
if (dev->bright_fd == -1) {
if (mraa_led_get_brightfd(dev) != MRAA_SUCCESS) {
return MRAA_ERROR_INVALID_RESOURCE;
}
} else {
lseek(dev->bright_fd, 0, SEEK_SET);
}
if (read(dev->bright_fd, buf, 3 * sizeof(char)) == -1) {
syslog(LOG_ERR, "led: read_brightness: Failed to read 'brightness': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
lseek(dev->bright_fd, 0, SEEK_SET);
return (int) atoi(buf);
}
int
mraa_led_read_max_brightness(mraa_led_context dev)
{
char buf[3];
if (dev == NULL) {
syslog(LOG_ERR, "led: read_max_brightness: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (dev->trig_fd != -1) {
close(dev->trig_fd);
dev->trig_fd = -1;
}
if (dev->bright_fd != -1) {
close(dev->bright_fd);
dev->bright_fd = -1;
}
if (dev->max_bright_fd == -1) {
if (mraa_led_get_maxbrightfd(dev) != MRAA_SUCCESS) {
return MRAA_ERROR_INVALID_RESOURCE;
}
} else {
lseek(dev->max_bright_fd, 0, SEEK_SET);
}
if (read(dev->max_bright_fd, buf, 3 * sizeof(char)) == -1) {
syslog(LOG_ERR, "led: read_max_brightness: Failed to read 'max_brightness': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
lseek(dev->max_bright_fd, 0, SEEK_SET);
return (int) atoi(buf);
}
mraa_result_t
mraa_led_set_trigger(mraa_led_context dev, const char* trigger)
{
char buf[MAX_SIZE];
int length;
if (dev == NULL) {
syslog(LOG_ERR, "led: set_trigger: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (dev->bright_fd != -1) {
close(dev->bright_fd);
dev->bright_fd = -1;
}
if (dev->max_bright_fd != -1) {
close(dev->max_bright_fd);
dev->max_bright_fd = -1;
}
if (trigger == NULL) {
syslog(LOG_ERR, "led: trigger: invalid trigger specified");
return MRAA_ERROR_INVALID_RESOURCE;
}
if (dev->trig_fd == -1) {
if (mraa_led_get_trigfd(dev) != MRAA_SUCCESS) {
return MRAA_ERROR_INVALID_RESOURCE;
}
}
if (lseek(dev->trig_fd, 0, SEEK_SET) == -1) {
syslog(LOG_ERR, "led: set_trigger: Failed to lseek 'trigger': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
length = snprintf(buf, sizeof(buf), "%s", trigger);
if (write(dev->trig_fd, buf, length * sizeof(char)) == -1) {
syslog(LOG_ERR, "led: set_trigger: Failed to write 'trigger': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
mraa_result_t
mraa_led_clear_trigger(mraa_led_context dev)
{
char buf[1] = { '0' };
if (dev == NULL) {
syslog(LOG_ERR, "led: clear_trigger: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (dev->trig_fd != -1) {
close(dev->trig_fd);
dev->trig_fd = -1;
}
if (dev->max_bright_fd != -1) {
close(dev->max_bright_fd);
dev->max_bright_fd = -1;
}
if (dev->bright_fd == -1) {
if (mraa_led_get_brightfd(dev) != MRAA_SUCCESS) {
return MRAA_ERROR_INVALID_RESOURCE;
}
}
if (lseek(dev->bright_fd, 0, SEEK_SET) == -1) {
syslog(LOG_ERR, "led: clear_trigger: Failed to lseek 'brightness': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
/* writing 0 to brightness clears trigger */
if (write(dev->bright_fd, buf, 1) == -1) {
syslog(LOG_ERR, "led: clear_trigger: Failed to write 'brightness': %s", strerror(errno));
return MRAA_ERROR_UNSPECIFIED;
}
return MRAA_SUCCESS;
}
mraa_result_t
mraa_led_close(mraa_led_context dev)
{
if (dev == NULL) {
syslog(LOG_ERR, "led: close: context is invalid");
return MRAA_ERROR_INVALID_HANDLE;
}
if (dev->bright_fd != -1) {
close(dev->bright_fd);
}
if (dev->trig_fd != -1) {
close(dev->trig_fd);
}
if (dev->max_bright_fd != -1) {
close(dev->max_bright_fd);
}
free(dev);
return MRAA_SUCCESS;
}

5
src/mraa.i
View File

@@ -13,6 +13,7 @@
#include "spi.hpp"
#include "aio.hpp"
#include "uart.hpp"
#include "led.hpp"
%}
%exception {
@@ -34,6 +35,7 @@
%template (spiFromDesc) mraa::initIo<mraa::Spi>;
%template (i2cFromDesc) mraa::initIo<mraa::I2c>;
%template (pwmFromDesc) mraa::initIo<mraa::Pwm>;
%template (ledFromDesc) mraa::initIo<mraa::Led>;
%ignore Aio(void* aio_context);
%ignore Pwm(void* pwm_context);
@@ -41,6 +43,7 @@
%ignore Spi(void* spi_context);
%ignore I2c(void* i2c_context);
%ignore Gpio(void* gpio_context);
%ignore Led(void* led_context);
%ignore Gpio::nop(uv_work_t* req);
%ignore Gpio::v8isr(uv_work_t* req);
@@ -59,3 +62,5 @@
%include "aio.hpp"
%include "uart.hpp"
%include "led.hpp"