blob: 1f542e19746286dd88af98395ec486e84a8f5579 [file] [log] [blame]
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <dirent.h>
#include <systemd/sd-bus.h>
/*
* These are control files that are present for each led under
*'/sys/class/leds/<led_name>/' which are used to trigger action
* on the respective leds by writing predefined data.
*/
const char *power_ctrl = "brightness";
const char *blink_ctrl = "trigger";
const char *duty_on = "delay_on";
const char *duty_off = "delay_off";
/*
* --------------------------------------------------
* Given the dbus path, returns the name of the LED
* --------------------------------------------------
*/
char *
get_led_name(const char *dbus_path)
{
char *led_name = NULL;
/* Get the led name from /org/openbmc/control/led/<name> */
led_name = strrchr(dbus_path, '/');
if(led_name)
{
led_name++;
}
return led_name;
}
/*
* -------------------------------------------------------------------------
* Writes the 'on / off / blink' trigger to leds.
* -------------------------------------------------------------------------
*/
int
write_to_led(const char *name, const char *ctrl_file, const char *value)
{
/* Generic error reporter. */
int rc = -1;
/* To get /sys/class/leds/<name>/<control file> */
char led_path[128] = {0};
int len = 0;
len = snprintf(led_path, sizeof(led_path),
"/sys/class/leds/%s/%s",name, ctrl_file);
if(len >= sizeof(led_path))
{
fprintf(stderr, "Error. LED path is too long. :[%d]\n",len);
return rc;
}
FILE *fp = fopen(led_path,"w");
if(fp == NULL)
{
fprintf(stderr,"Error:[%s] opening:[%s]\n",strerror(errno),led_path);
return rc;
}
rc = fwrite(value, strlen(value), 1, fp);
if(rc != 1)
{
fprintf(stderr, "Error:[%s] writing to :[%s]\n",strerror(errno),led_path);
}
fclose(fp);
/* When we get here, rc would be what it was from writing to the file */
return (rc == 1) ? 0 : -1;
}
/*
* ----------------------------------------------------------------
* Router function for any LED operations that come via dbus
*----------------------------------------------------------------
*/
static int
led_function_router(sd_bus_message *msg, void *user_data,
sd_bus_error *ret_error)
{
/* Generic error reporter. */
int rc = -1;
/* Extract the led name from the full dbus path */
const char *led_path = sd_bus_message_get_path(msg);
if(led_path == NULL)
{
fprintf(stderr, "Error. LED path is empty");
return sd_bus_reply_method_return(msg, "i", rc);
}
char *led_name = get_led_name(led_path);
if(led_name == NULL)
{
fprintf(stderr, "Invalid LED name for path :[%s]\n",led_path);
return sd_bus_reply_method_return(msg, "i", rc);
}
/* Now that we have the LED name, get the Operation. */
const char *led_function = sd_bus_message_get_member(msg);
if(led_function == NULL)
{
fprintf(stderr, "Null LED function specificed for : [%s]\n",led_name);
return sd_bus_reply_method_return(msg, "i", rc);
}
/* Route the user action to appropriate handlers. */
if( (strcmp(led_function, "setOn") == 0) ||
(strcmp(led_function, "setOff") == 0))
{
rc = led_stable_state_function(led_name, led_function);
return sd_bus_reply_method_return(msg, "i", rc);
}
else if( (strcmp(led_function, "setBlinkFast") == 0) ||
(strcmp(led_function, "setBlinkSlow") == 0))
{
rc = led_default_blink(led_name, led_function);
return sd_bus_reply_method_return(msg, "i", rc);
}
else if(strcmp(led_function, "BlinkCustom") == 0)
{
rc = led_custom_blink(led_name, msg);
return sd_bus_reply_method_return(msg, "i", rc);
}
else if(strcmp(led_function, "GetLedState") == 0)
{
char value_str[10] = {0};
const char *led_state = NULL;
rc = read_led(led_name, power_ctrl, value_str, sizeof(value_str)-1);
if(rc >= 0)
{
/* LED is active HI */
led_state = strtoul(value_str, NULL, 0) ? "On" : "Off";
}
return sd_bus_reply_method_return(msg, "is", rc, led_state);
}
else
{
fprintf(stderr,"Invalid LED function:[%s]\n",led_function);
}
return sd_bus_reply_method_return(msg, "i", rc);
}
/*
* --------------------------------------------------------------
* Turn On or Turn Off the LED
* --------------------------------------------------------------
*/
int
led_stable_state_function(char *led_name, char *led_function)
{
/* Generic error reporter. */
int rc = -1;
const char *value = NULL;
if(strcmp(led_function, "setOff") == 0)
{
/* LED active low */
value = "0";
}
else if(strcmp(led_function, "setOn") == 0)
{
value = "255";
}
else
{
fprintf(stderr,"Invalid LED stable state operation:[%s] \n",led_function);
return rc;
}
/*
* Before doing anything, need to turn off the blinking
* if there is one in progress by writing 'none' to trigger
*/
rc = write_to_led(led_name, blink_ctrl, "none");
if(rc < 0)
{
fprintf(stderr,"Error disabling blink. Function:[%s]\n", led_function);
return rc;
}
/*
* Open the brightness file and write corresponding values.
*/
rc = write_to_led(led_name, power_ctrl, value);
if(rc < 0)
{
fprintf(stderr,"Error driving LED. Function:[%s]\n", led_function);
}
return rc;
}
//-----------------------------------------------------------------------------------
// Given the on and off duration, applies the action on the specified LED.
//-----------------------------------------------------------------------------------
int
blink_led(const char *led_name, const char *on_duration, const char *off_duration)
{
/* Generic error reporter */
int rc = -1;
/* Protocol demands that 'timer' be echoed to 'trigger' */
rc = write_to_led(led_name, blink_ctrl, "timer");
if(rc < 0)
{
fprintf(stderr,"Error writing timer to Led:[%s]\n", led_name);
return rc;
}
/*
* After writing 'timer to 'trigger', 2 new files get generated namely
*'delay_on' and 'delay_off' which are telling the time duration for a
* particular LED on and off.
*/
rc = write_to_led(led_name, duty_on, on_duration);
if(rc < 0)
{
fprintf(stderr,"Error writing [%s] to delay_on:[%s]\n",on_duration,led_name);
return rc;
}
rc = write_to_led(led_name, duty_off, off_duration);
if(rc < 0)
{
fprintf(stderr,"Error writing [%s] to delay_off:[%s]\n",off_duration,led_name);
}
return rc;
}
/*
* ----------------------------------------------------
* Default blink action on the LED.
* ----------------------------------------------------
*/
int
led_default_blink(char *led_name, char *blink_type)
{
/* Generic error reporter */
int rc = -1;
/* How long the LED needs to be in on and off state while blinking */
const char *on_duration = NULL;
const char *off_duration = NULL;
if(strcmp(blink_type, "setBlinkSlow") == 0)
{
//*Delay 900 millisec before 'on' and delay 900 millisec before off */
on_duration = "900";
off_duration = "900";
}
else if(strcmp(blink_type, "setBlinkFast") == 0)
{
/* Delay 200 millisec before 'on' and delay 200 millisec before off */
on_duration = "200";
off_duration = "200";
}
else
{
fprintf(stderr,"Invalid blink operation:[%s]\n",blink_type);
return rc;
}
rc = blink_led(led_name, on_duration, off_duration);
return rc;
}
/*
* -------------------------------------------------
* Blinks at user defined 'on' and 'off' intervals.
* -------------------------------------------------
*/
int
led_custom_blink(const char *led_name, sd_bus_message *msg)
{
/* Generic error reporter. */
int rc = -1;
int led_len = 0;
/* User supplied 'on' and 'off' duration converted into string */
char on_duration[32] = {0};
char off_duration[32] = {0};
/* User supplied 'on' and 'off' duration */
uint32_t user_input_on = 0;
uint32_t user_input_off = 0;
/* Extract values into 'ss' ( string, string) */
rc = sd_bus_message_read(msg, "uu", &user_input_on, &user_input_off);
if(rc < 0)
{
fprintf(stderr, "Failed to read 'on' and 'off' duration.[%s]\n", strerror(-rc));
}
else
{
/*
* Converting user supplied integer arguments into string as required by
* sys interface. The top level REST will make sure that an error is
* thrown right away on invalid inputs. However, REST is allowing the
* unsigned decimal and floating numbers but when its received here, its
* received as decimal so no input validation needed.
*/
led_len = snprintf(on_duration, sizeof(on_duration),
"%d",user_input_on);
if(led_len >= sizeof(on_duration))
{
fprintf(stderr, "Error. Blink ON duration is too long. :[%d]\n",led_len);
return rc;
}
led_len = snprintf(off_duration, sizeof(off_duration),
"%d",user_input_off);
if(led_len >= sizeof(off_duration))
{
fprintf(stderr, "Error. Blink OFF duration is too long. :[%d]\n",led_len);
return rc;
}
/* We are good here.*/
rc = blink_led(led_name, on_duration, off_duration);
}
return rc;
}
/*
* ---------------------------------------------------------------
* Gets the current value of passed in LED file
* Mainly used for reading 'brightness'
* NOTE : It is the responsibility of the caller to allocate
* sufficient space for buffer. This will read upto user supplied
* size -or- entire contents of file whichever is smaller
* ----------------------------------------------------------------
*/
int
read_led(const char *name, const char *ctrl_file,
void *value, const size_t len)
{
/* Generic error reporter. */
int rc = -1;
int count = 0;
if(value == NULL || len <= 0)
{
fprintf(stderr, "Invalid buffer passed to LED read\n");
return rc;
}
/* To get /sys/class/leds/<name>/<control file> */
char led_path[128] = {0};
int led_len = 0;
led_len = snprintf(led_path, sizeof(led_path),
"/sys/class/leds/%s/%s",name, ctrl_file);
if(led_len >= sizeof(led_path))
{
fprintf(stderr, "Error. LED path is too long. :[%d]\n",led_len);
return rc;
}
FILE *fp = fopen(led_path,"rb");
if(fp == NULL)
{
fprintf(stderr,"Error:[%s] opening:[%s]\n",strerror(errno),led_path);
return rc;
}
char *sysfs_value = (char *)value;
while(!feof(fp) && (count < len))
{
sysfs_value[count++] = fgetc(fp);
}
fclose(fp);
return 0;
}
/*
* -----------------------------------------------
* Dbus Services offered by this LED controller
* -----------------------------------------------
*/
static const sd_bus_vtable led_control_vtable[] =
{
SD_BUS_VTABLE_START(0),
SD_BUS_METHOD("setOn", "", "i", &led_function_router, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("setOff", "", "i", &led_function_router, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("setBlinkFast", "", "i", &led_function_router, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("setBlinkSlow", "", "i", &led_function_router, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("GetLedState", "", "is", &led_function_router, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_METHOD("BlinkCustom", "uu", "i", &led_function_router, SD_BUS_VTABLE_UNPRIVILEGED),
SD_BUS_VTABLE_END,
};
/*
* ---------------------------------------------
* Interested in all files except standard ones
* ---------------------------------------------
*/
int
led_select(const struct dirent *entry)
{
if( (strcmp(entry->d_name, ".") == 0) ||
(strcmp(entry->d_name, "..") == 0))
{
return 0;
}
return 1;
}
/*
* ------------------------------------------------
* Called as part of setting up skeleton services.
* -----------------------------------------------
*/
int
start_led_services()
{
/* Generic error reporter. */
int rc = -1;
int num_leds = 0;
int count_leds = 0;
/* Bus and slot where we are offering the LED dbus service. */
sd_bus *bus_type = NULL;
sd_bus_slot *led_slot = NULL;
/* For walking '/sys/class/leds/' looking for names of LED.*/
struct dirent **led_list;
/* Get a hook onto system bus. */
rc = sd_bus_open_system(&bus_type);
if(rc < 0)
{
fprintf(stderr,"Error opening system bus.\n");
return rc;
}
count_leds = num_leds = scandir("/sys/class/leds/",
&led_list, led_select, alphasort);
if(num_leds <= 0)
{
fprintf(stderr,"No LEDs present in the system\n");
sd_bus_slot_unref(led_slot);
sd_bus_unref(bus_type);
return rc;
}
/* Fully qualified Dbus object for a particular LED */
char led_object[128] = {0};
int len = 0;
/* For each led present, announce the service on dbus. */
while(num_leds--)
{
memset(led_object, 0x0, sizeof(led_object));
len = snprintf(led_object, sizeof(led_object), "%s%s",
"/org/openbmc/control/led/", led_list[num_leds]->d_name);
if(len >= sizeof(led_object))
{
fprintf(stderr, "Error. LED object is too long:[%d]\n",len);
rc = -1;
break;
}
/* Install the object */
rc = sd_bus_add_object_vtable(bus_type,
&led_slot,
led_object, /* object path */
"org.openbmc.Led", /* interface name */
led_control_vtable,
NULL);
if(rc < 0)
{
fprintf(stderr, "Failed to add object to dbus: %s\n", strerror(-rc));
break;
}
}
/* Done with all registration. */
while(count_leds > 0)
{
free(led_list[--count_leds]);
}
free(led_list);
/* If we had success in adding the providers, request for a bus name. */
if(rc == 0)
{
/* Take one in OpenBmc */
rc = sd_bus_request_name(bus_type, "org.openbmc.control.led", 0);
if(rc < 0)
{
fprintf(stderr, "Failed to acquire service name: %s\n", strerror(-rc));
}
else
{
for(;;)
{
/* Process requests */
rc = sd_bus_process(bus_type, NULL);
if(rc < 0)
{
fprintf(stderr, "Failed to process bus: %s\n", strerror(-rc));
break;
}
if(rc > 0)
{
continue;
}
rc = sd_bus_wait(bus_type, (uint64_t) - 1);
if(rc < 0)
{
fprintf(stderr, "Failed to wait on bus: %s\n", strerror(-rc));
break;
}
}
}
}
sd_bus_slot_unref(led_slot);
sd_bus_unref(bus_type);
return rc;
}
int
main(void)
{
int rc = 0;
/* This call is not supposed to return. If it does, then an error */
rc = start_led_services();
if(rc < 0)
{
fprintf(stderr, "Error starting LED Services. Exiting");
}
return rc;
}