xf86-video-intel: src/backlight.c src/backlight.h src/sna/sna_display.c src/uxa/intel_display.c

[Chris Wilson]

 src/backlight.c         |   60 +++++++++++++++++++++++++++---------------------
 src/backlight.h         |    2 -
 src/sna/sna_display.c   |    2 -
 src/uxa/intel_display.c |    2 -
 4 files changed, 37 insertions(+), 29 deletions(-)

New commits:
commit b24e7581bd1e5a0215cb73ec87093ebf03c20278
Author: Chris Wilson <chris at chris-wilson.co.uk>
Date:   Wed Jun 17 17:55:04 2015 +0100

    backlight: Factor known names into preferred interfaces
    
    Since the /sys/device/backlight never turned up we face an issue with
    disambiguating the backlight on multi-GPU devices. Both intel_backlight
    and nv_backlight are presented are raw interfaces, and on modern systems
    the ACPI interface is defunct, so we need a way to distinguish them. So,
    we fallback to our priority table of known interfaces and rank them
    accordingly, first by class (platform, native, raw) and then by priority.
    
    Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>

diff --git a/src/backlight.c b/src/backlight.c
index c65e466..d020a7c 100644
--- a/src/backlight.c
+++ b/src/backlight.c
@@ -152,12 +152,9 @@ int backlight_open(struct backlight *b, char *iface)
 	return param.curval;
 }
 
-enum backlight_type backlight_exists(const char *iface)
+int backlight_exists(const char *iface)
 {
-	if (iface != NULL)
-		return BL_NONE;
-
-	return BL_PLATFORM;
+	return iface == NULL;
 }
 
 int backlight_on(struct backlight *b)
@@ -250,10 +247,10 @@ static const char *known_interfaces[] = {
 	"intel_backlight",
 };
 
-static enum backlight_type __backlight_type(const char *iface)
+static int __backlight_type(const char *iface)
 {
 	char buf[1024];
-	int fd, v;
+	int fd, v, i;
 
 	v = -1;
 	fd = __backlight_open(iface, "type", O_RDONLY);
@@ -267,39 +264,41 @@ static enum backlight_type __backlight_type(const char *iface)
 		buf[v] = '\0';
 
 		if (strcmp(buf, "raw") == 0)
-			v = BL_RAW;
+			v = BL_RAW << 8;
 		else if (strcmp(buf, "platform") == 0)
-			v = BL_PLATFORM;
+			v = BL_PLATFORM << 8;
 		else if (strcmp(buf, "firmware") == 0)
-			v = BL_FIRMWARE;
+			v = BL_FIRMWARE << 8;
 		else
-			v = BL_NAMED;
+			v = BL_NAMED << 8;
 	} else
-		v = BL_NAMED;
+		v = BL_NAMED << 8;
 
-	if (v == BL_NAMED) {
-		int i;
-		for (i = 0; i < ARRAY_SIZE(known_interfaces); i++) {
-			if (strcmp(iface, known_interfaces[i]) == 0)
-				break;
-		}
-		v += i;
+	for (i = 0; i < ARRAY_SIZE(known_interfaces); i++) {
+		if (strcmp(iface, known_interfaces[i]) == 0)
+			break;
 	}
+	v += i;
 
 	return v;
 }
 
-enum backlight_type backlight_exists(const char *iface)
+static int __backlight_exists(const char *iface)
 {
 	if (__backlight_read(iface, "brightness") < 0)
-		return BL_NONE;
+		return -1;
 
 	if (__backlight_read(iface, "max_brightness") <= 0)
-		return BL_NONE;
+		return -1;
 
 	return __backlight_type(iface);
 }
 
+int backlight_exists(const char *iface)
+{
+	return __backlight_exists(iface) != -1;
+}
+
 static int __backlight_init(struct backlight *b, char *iface, int fd)
 {
 	b->fd = fd_move_cloexec(fd_set_nonblock(fd));
@@ -405,7 +404,10 @@ __backlight_find(void)
 			continue;
 
 		/* Fallback to priority list of known iface for old kernels */
-		v = backlight_exists(de->d_name);
+		v = __backlight_exists(de->d_name);
+		if (v < 0)
+			continue;
+
 		if (v < best_type) {
 			char *copy = strdup(de->d_name);
 			if (copy) {
@@ -422,14 +424,17 @@ __backlight_find(void)
 
 int backlight_open(struct backlight *b, char *iface)
 {
-	int level;
+	int level, type;
 
 	if (iface == NULL)
 		iface = __backlight_find();
 	if (iface == NULL)
 		goto err;
 
-	b->type = __backlight_type(iface);
+	type = __backlight_type(iface);
+	if (type < 0)
+		goto err;
+	b->type = type >> 8;
 
 	b->max = __backlight_read(iface, "max_brightness");
 	if (b->max <= 0)
@@ -549,7 +554,10 @@ char *backlight_find_for_device(struct pci_device *pci)
 		if (*de->d_name == '.')
 			continue;
 
-		v = backlight_exists(de->d_name);
+		v = __backlight_exists(de->d_name);
+		if (v < 0)
+			continue;
+
 		if (v < best_type) {
 			char *copy = strdup(de->d_name);
 			if (copy) {
diff --git a/src/backlight.h b/src/backlight.h
index bb0e28b..ba17755 100644
--- a/src/backlight.h
+++ b/src/backlight.h
@@ -43,7 +43,7 @@ struct backlight {
 	int pid, fd;
 };
 
-enum backlight_type backlight_exists(const char *iface);
+int backlight_exists(const char *iface);
 
 void backlight_init(struct backlight *backlight);
 int backlight_open(struct backlight *backlight, char *iface);
diff --git a/src/sna/sna_display.c b/src/sna/sna_display.c
index efc5fc9..53eb9ca 100644
--- a/src/sna/sna_display.c
+++ b/src/sna/sna_display.c
@@ -767,7 +767,7 @@ has_user_backlight_override(xf86OutputPtr output)
 	if (*str == '\0')
 		return (char *)str;
 
-	if (backlight_exists(str) == BL_NONE) {
+	if (!backlight_exists(str)) {
 		xf86DrvMsg(output->scrn->scrnIndex, X_ERROR,
 			   "Unrecognised backlight control interface '%s'\n",
 			   str);
diff --git a/src/uxa/intel_display.c b/src/uxa/intel_display.c
index 0cdc8d2..8bf0184 100644
--- a/src/uxa/intel_display.c
+++ b/src/uxa/intel_display.c
@@ -192,7 +192,7 @@ intel_output_backlight_init(xf86OutputPtr output)
 
 	str = xf86GetOptValString(intel->Options, OPTION_BACKLIGHT);
 	if (str != NULL) {
-		if (backlight_exists(str) != BL_NONE) {
+		if (backlight_exists(str)) {
 			intel_output->backlight_active_level =
 				backlight_open(&intel_output->backlight,
 					       strdup(str));