ACK: [PATCH] acpi: brightness: use /sys/class/backlight interface (LP: #1250517)

[Alex Hung]

On 11/12/2013 11:31 PM, Colin King wrote:
> From: Colin Ian King <colin.king at canonical.com>
>
> Use /sys/class/backlight and fall back to use the older
> /sys/devices/virtual/backlight if the former is not available for
> older releases.
>
> Signed-off-by: Colin Ian King <colin.king at canonical.com>
> ---
>   src/acpi/brightness/brightness.c | 62 +++++++++++++++++++++++-----------------
>   1 file changed, 36 insertions(+), 26 deletions(-)
>
> diff --git a/src/acpi/brightness/brightness.c b/src/acpi/brightness/brightness.c
> index 8853979..fd333d5 100644
> --- a/src/acpi/brightness/brightness.c
> +++ b/src/acpi/brightness/brightness.c
> @@ -29,28 +29,41 @@
>   #include <limits.h>
>   #include <dirent.h>
>
> -static DIR *brightnessdir;
> +static DIR *brightness_dir;
> +static char *brightness_path;
>
>   static int skip_tests = 0;
>
> -#define BRIGHTNESS_PATH	"/sys/devices/virtual/backlight"
> -
>   static int brightness_init(fwts_framework *fw)
>   {
> -	if (!(brightnessdir = opendir(BRIGHTNESS_PATH))) {
> -		fwts_failed(fw, LOG_LEVEL_LOW, "BacklightNoPath", "No %s directory available: cannot test.", BRIGHTNESS_PATH);
> -		return FWTS_ERROR;
> +	int i;
> +	static char *sys_path[] = {
> +		"/sys/class/backlight",
> +		"/sys/devices/virtual/backlight",
> +		NULL
> +	};
> +
> +	brightness_path = NULL;
> +	brightness_dir = NULL;
> +
> +	for (i = 0; sys_path[i]; i++) {
> +		brightness_dir = opendir(sys_path[i]);
> +		if (brightness_dir) {
> +			brightness_path = sys_path[i];
> +			return FWTS_OK;
> +		}
>   	}
>
> -	return FWTS_OK;
> +	fwts_failed(fw, LOG_LEVEL_LOW, "BacklightNoPath", "No sysfs backlight directory available: cannot test.");
> +	return FWTS_ERROR;
>   }
>
>   static int brightness_deinit(fwts_framework *fw)
>   {
>   	FWTS_UNUSED(fw);
>
> -	if (brightnessdir)
> -		closedir(brightnessdir);
> +	if (brightness_dir)
> +		closedir(brightness_dir);
>
>   	return FWTS_OK;
>   }
> @@ -60,7 +73,7 @@ static int get_setting(char *entry_name, char *setting, int *value)
>   	char path[PATH_MAX];
>   	FILE *fp;
>
> -	snprintf(path, sizeof(path), BRIGHTNESS_PATH "/%s/%s", entry_name, setting);
> +	snprintf(path, sizeof(path), "%s/%s/%s", brightness_path, entry_name, setting);
>   	if ((fp = fopen(path, "r")) == NULL)
>   		return -1;
>
> @@ -79,7 +92,7 @@ static int set_setting(char *entry_name, char *setting, int value)
>   	char path[PATH_MAX];
>   	FILE *fp;
>
> -	snprintf(path, sizeof(path), BRIGHTNESS_PATH "/%s/%s", entry_name, setting);
> +	snprintf(path, sizeof(path), "%s/%s/%s", brightness_path, entry_name, setting);
>   	if ((fp = fopen(path, "w")) == NULL)
>   		return -1;
>
> @@ -101,9 +114,9 @@ static int brightness_test1(fwts_framework *fw)
>
>   	skip_tests = 1;
>
> -	rewinddir(brightnessdir);
> +	rewinddir(brightness_dir);
>   	do {
> -		entry = readdir(brightnessdir);
> +		entry = readdir(brightness_dir);
>   		if (entry && strlen(entry->d_name)>2) {
>   			if (get_setting(entry->d_name, "max_brightness", &max_brightness) == FWTS_OK) {
>   				if (max_brightness <= 0)
> @@ -142,16 +155,15 @@ static int brightness_test2(fwts_framework *fw)
>   		return FWTS_SKIP;
>   	}
>
> -	rewinddir(brightnessdir);
> +	rewinddir(brightness_dir);
>   	do {
> -		entry = readdir(brightnessdir);
> +		entry = readdir(brightness_dir);
>   		if (entry && strlen(entry->d_name)>2) {
>   			if (get_setting(entry->d_name, "max_brightness", &max_brightness) == FWTS_OK) {
>   				if (max_brightness <= 0) {
>   					fwts_failed(fw, LOG_LEVEL_HIGH, "BrightnessMaxTest2", "Maximum brightness for %s is %d and should be > 0.", entry->d_name, max_brightness);
>   					continue;
>   				}
> -				
>   				if (get_setting(entry->d_name, "actual_brightness", &saved_brightness) == FWTS_OK) {
>   					int i;
>   					int failed = 0;
> @@ -194,16 +206,15 @@ static int brightness_test3(fwts_framework *fw)
>   		return FWTS_SKIP;
>   	}
>
> -	rewinddir(brightnessdir);
> +	rewinddir(brightness_dir);
>   	do {
> -		entry = readdir(brightnessdir);
> +		entry = readdir(brightness_dir);
>   		if (entry && strlen(entry->d_name)>2) {
>   			if (get_setting(entry->d_name, "max_brightness", &max_brightness) == FWTS_OK) {
>   				if (max_brightness <= 0) {
>   					fwts_failed(fw, LOG_LEVEL_HIGH, "BrightnessMaxTest3", "Maximum brightness for %s is %d and should be > 0.", entry->d_name, max_brightness);
>   					continue;
>   				}
> -				
>   				if (get_setting(entry->d_name, "actual_brightness", &saved_brightness) == FWTS_OK) {
>   					int ch;
>
> @@ -246,9 +257,9 @@ static int brightness_test4(fwts_framework *fw)
>   		return FWTS_SKIP;
>   	}
>
> -	rewinddir(brightnessdir);
> +	rewinddir(brightness_dir);
>   	do {
> -		entry = readdir(brightnessdir);
> +		entry = readdir(brightness_dir);
>   		if (entry && strlen(entry->d_name)>2) {
>   			if (get_setting(entry->d_name, "max_brightness", &max_brightness) == FWTS_OK) {
>   				int i;
> @@ -262,7 +273,7 @@ static int brightness_test4(fwts_framework *fw)
>   				if (get_setting(entry->d_name, "actual_brightness", &saved_brightness) == FWTS_OK) {
>   					long delay = 5000000/max_brightness;
>   					int ch;
> -		
> +
>   					if (delay > 1000000)
>   						delay = 1000000;
>
> @@ -301,7 +312,7 @@ static int brightness_wait_event(fwts_framework *fw)
>   		fwts_log_error(fw, "Cannot connect to acpid.");
>   		return FWTS_ERROR;
>   	}
> -	
> +
>   	for (i=0;i<=20;i++) {
>   		if ((buffer = fwts_acpi_event_read(fd, &len, 1)) != NULL)
>   			if (strstr(buffer, "video")) {
> @@ -323,9 +334,9 @@ static int brightness_test5(fwts_framework *fw)
>   	struct dirent *entry;
>   	int saved_brightness;
>
> -	rewinddir(brightnessdir);
> +	rewinddir(brightness_dir);
>   	do {
> -		entry = readdir(brightnessdir);
> +		entry = readdir(brightness_dir);
>   		if (entry && strlen(entry->d_name)>2) {
>   			if (get_setting(entry->d_name, "actual_brightness", &saved_brightness) != FWTS_OK) {
>   				fwts_failed(fw, LOG_LEVEL_HIGH, "BrightnessNotExist", "Actual brightness could not be accessed for %s.", entry->d_name);
> @@ -350,7 +361,6 @@ static int brightness_test5(fwts_framework *fw)
>   				}
>
>   				tmp = (saved_brightness > 0) ? saved_brightness : 1;
> -					
>   				set_setting(entry->d_name, "brightness", tmp);
>   				fwts_printf(fw, "==== Press the brightness DOWN hotkey for %s ====\n", entry->d_name);
>
>

Acked-by: Alex Hung <alex.hung at canonical.com>