1 files changed, 140 insertions, 111 deletions

diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index a768a69d58d2..b03bf5153b0f 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -304,8 +304,8 @@ static struct {
 	u32 hotkey_tablet:1;
 	u32 light:1;
 	u32 light_status:1;
-	u32 bright_16levels:1;
 	u32 bright_acpimode:1;
+	u32 bright_unkfw:1;
 	u32 wan:1;
 	u32 uwb:1;
 	u32 fan_ctrl_status_undef:1;
@@ -368,6 +368,9 @@ struct tpacpi_led_classdev {
 	unsigned int led;
 };
 
+/* brightness level capabilities */
+static unsigned int bright_maxlvl;	/* 0 = unknown */
+
 #ifdef CONFIG_THINKPAD_ACPI_DEBUGFACILITIES
 static int dbg_wlswemul;
 static int tpacpi_wlsw_emulstate;
@@ -1051,80 +1054,6 @@ static void tpacpi_disable_brightness_delay(void)
 			"ACPI backlight control delay disabled\n");
 }
 
-static int __init tpacpi_query_bcl_levels(acpi_handle handle)
-{
-	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
-	union acpi_object *obj;
-	int rc;
-
-	if (ACPI_SUCCESS(acpi_evaluate_object(handle, NULL, NULL, &buffer))) {
-		obj = (union acpi_object *)buffer.pointer;
-		if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
-			printk(TPACPI_ERR "Unknown _BCL data, "
-			       "please report this to %s\n", TPACPI_MAIL);
-			rc = 0;
-		} else {
-			rc = obj->package.count;
-		}
-	} else {
-		return 0;
-	}
-
-	kfree(buffer.pointer);
-	return rc;
-}
-
-static acpi_status __init tpacpi_acpi_walk_find_bcl(acpi_handle handle,
-					u32 lvl, void *context, void **rv)
-{
-	char name[ACPI_PATH_SEGMENT_LENGTH];
-	struct acpi_buffer buffer = { sizeof(name), &name };
-
-	if (ACPI_SUCCESS(acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer)) &&
-	    !strncmp("_BCL", name, sizeof(name) - 1)) {
-		BUG_ON(!rv || !*rv);
-		**(int **)rv = tpacpi_query_bcl_levels(handle);
-		return AE_CTRL_TERMINATE;
-	} else {
-		return AE_OK;
-	}
-}
-
-/*
- * Returns 0 (no ACPI _BCL or _BCL invalid), or size of brightness map
- */
-static int __init tpacpi_check_std_acpi_brightness_support(void)
-{
-	int status;
-	int bcl_levels = 0;
-	void *bcl_ptr = &bcl_levels;
-
-	if (!vid_handle) {
-		TPACPI_ACPIHANDLE_INIT(vid);
-	}
-	if (!vid_handle)
-		return 0;
-
-	/*
-	 * Search for a _BCL method, and execute it.  This is safe on all
-	 * ThinkPads, and as a side-effect, _BCL will place a Lenovo Vista
-	 * BIOS in ACPI backlight control mode.  We do NOT have to care
-	 * about calling the _BCL method in an enabled video device, any
-	 * will do for our purposes.
-	 */
-
-	status = acpi_walk_namespace(ACPI_TYPE_METHOD, vid_handle, 3,
-				     tpacpi_acpi_walk_find_bcl, NULL, NULL,
-				     &bcl_ptr);
-
-	if (ACPI_SUCCESS(status) && bcl_levels > 2) {
-		tp_features.bright_acpimode = 1;
-		return (bcl_levels - 2);
-	}
-
-	return 0;
-}
-
 static void printk_deprecated_attribute(const char * const what,
 					const char * const details)
 {
@@ -3420,11 +3349,8 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
 	}
 
 	/* Do not issue duplicate brightness change events to
-	 * userspace */
-	if (!tp_features.bright_acpimode)
-		/* update bright_acpimode... */
-		tpacpi_check_std_acpi_brightness_support();
-
+	 * userspace. tpacpi_detect_brightness_capabilities() must have
+	 * been called before this point  */
 	if (tp_features.bright_acpimode && acpi_video_backlight_support()) {
 		printk(TPACPI_INFO
 		       "This ThinkPad has standard ACPI backlight "
@@ -5989,7 +5915,7 @@ static unsigned int tpacpi_brightness_nvram_get(void)
 	lnvram = (nvram_read_byte(TP_NVRAM_ADDR_BRIGHTNESS)
 		  & TP_NVRAM_MASK_LEVEL_BRIGHTNESS)
 		  >> TP_NVRAM_POS_LEVEL_BRIGHTNESS;
-	lnvram &= (tp_features.bright_16levels) ? 0x0f : 0x07;
+	lnvram &= bright_maxlvl;
 
 	return lnvram;
 }
@@ -6098,8 +6024,7 @@ static int brightness_set(unsigned int value)
 {
 	int res;
 
-	if (value > ((tp_features.bright_16levels)? 15 : 7) ||
-	    value < 0)
+	if (value > bright_maxlvl || value < 0)
 		return -EINVAL;
 
 	vdbg_printk(TPACPI_DBG_BRGHT,
@@ -6174,6 +6099,80 @@ static struct backlight_ops ibm_backlight_data = {
 
 /* --------------------------------------------------------------------- */
 
+static int __init tpacpi_query_bcl_levels(acpi_handle handle)
+{
+	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
+	union acpi_object *obj;
+	int rc;
+
+	if (ACPI_SUCCESS(acpi_evaluate_object(handle, NULL, NULL, &buffer))) {
+		obj = (union acpi_object *)buffer.pointer;
+		if (!obj || (obj->type != ACPI_TYPE_PACKAGE)) {
+			printk(TPACPI_ERR "Unknown _BCL data, "
+			       "please report this to %s\n", TPACPI_MAIL);
+			rc = 0;
+		} else {
+			rc = obj->package.count;
+		}
+	} else {
+		return 0;
+	}
+
+	kfree(buffer.pointer);
+	return rc;
+}
+
+static acpi_status __init tpacpi_acpi_walk_find_bcl(acpi_handle handle,
+					u32 lvl, void *context, void **rv)
+{
+	char name[ACPI_PATH_SEGMENT_LENGTH];
+	struct acpi_buffer buffer = { sizeof(name), &name };
+
+	if (ACPI_SUCCESS(acpi_get_name(handle, ACPI_SINGLE_NAME, &buffer)) &&
+	    !strncmp("_BCL", name, sizeof(name) - 1)) {
+		BUG_ON(!rv || !*rv);
+		**(int **)rv = tpacpi_query_bcl_levels(handle);
+		return AE_CTRL_TERMINATE;
+	} else {
+		return AE_OK;
+	}
+}
+
+/*
+ * Returns 0 (no ACPI _BCL or _BCL invalid), or size of brightness map
+ */
+static unsigned int __init tpacpi_check_std_acpi_brightness_support(void)
+{
+	int status;
+	int bcl_levels = 0;
+	void *bcl_ptr = &bcl_levels;
+
+	if (!vid_handle)
+		TPACPI_ACPIHANDLE_INIT(vid);
+
+	if (!vid_handle)
+		return 0;
+
+	/*
+	 * Search for a _BCL method, and execute it.  This is safe on all
+	 * ThinkPads, and as a side-effect, _BCL will place a Lenovo Vista
+	 * BIOS in ACPI backlight control mode.  We do NOT have to care
+	 * about calling the _BCL method in an enabled video device, any
+	 * will do for our purposes.
+	 */
+
+	status = acpi_walk_namespace(ACPI_TYPE_METHOD, vid_handle, 3,
+				     tpacpi_acpi_walk_find_bcl, NULL, NULL,
+				     &bcl_ptr);
+
+	if (ACPI_SUCCESS(status) && bcl_levels > 2) {
+		tp_features.bright_acpimode = 1;
+		return bcl_levels - 2;
+	}
+
+	return 0;
+}
+
 /*
  * These are only useful for models that have only one possibility
  * of GPU.  If the BIOS model handles both ATI and Intel, don't use
@@ -6204,6 +6203,47 @@ static const struct tpacpi_quirk brightness_quirk_table[] __initconst = {
 	TPACPI_Q_IBM('7', '5', TPACPI_BRGHT_Q_NOEC),	/* X41 Tablet */
 };
 
+/*
+ * Returns < 0 for error, otherwise sets tp_features.bright_*
+ * and bright_maxlvl.
+ */
+static void __init tpacpi_detect_brightness_capabilities(void)
+{
+	unsigned int b;
+
+	vdbg_printk(TPACPI_DBG_INIT,
+		    "detecting firmware brightness interface capabilities\n");
+
+	/* we could run a quirks check here (same table used by
+	 * brightness_init) if needed */
+
+	/*
+	 * We always attempt to detect acpi support, so as to switch
+	 * Lenovo Vista BIOS to ACPI brightness mode even if we are not
+	 * going to publish a backlight interface
+	 */
+	b = tpacpi_check_std_acpi_brightness_support();
+	switch (b) {
+	case 16:
+		bright_maxlvl = 15;
+		printk(TPACPI_INFO
+		       "detected a 16-level brightness capable ThinkPad\n");
+		break;
+	case 8:
+	case 0:
+		bright_maxlvl = 7;
+		printk(TPACPI_INFO
+		       "detected a 8-level brightness capable ThinkPad\n");
+		break;
+	default:
+		printk(TPACPI_ERR
+		       "Unsupported brightness interface, "
+		       "please contact %s\n", TPACPI_MAIL);
+		tp_features.bright_unkfw = 1;
+		bright_maxlvl = b - 1;
+	}
+}
+
 static int __init brightness_init(struct ibm_init_struct *iibm)
 {
 	struct backlight_properties props;
@@ -6217,14 +6257,13 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
 	quirks = tpacpi_check_quirks(brightness_quirk_table,
 				ARRAY_SIZE(brightness_quirk_table));
 
-	/*
-	 * We always attempt to detect acpi support, so as to switch
-	 * Lenovo Vista BIOS to ACPI brightness mode even if we are not
-	 * going to publish a backlight interface
-	 */
-	b = tpacpi_check_std_acpi_brightness_support();
-	if (b > 0) {
+	/* tpacpi_detect_brightness_capabilities() must have run already */
+
+	/* if it is unknown, we don't handle it: it wouldn't be safe */
+	if (tp_features.bright_unkfw)
+		return 1;
 
+	if (tp_features.bright_acpimode) {
 		if (acpi_video_backlight_support()) {
 			if (brightness_enable > 1) {
 				printk(TPACPI_NOTICE
@@ -6253,15 +6292,6 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
 		return 1;
 	}
 
-	if (b > 16) {
-		printk(TPACPI_ERR
-		       "Unsupported brightness interface, "
-		       "please contact %s\n", TPACPI_MAIL);
-		return 1;
-	}
-	if (b == 16)
-		tp_features.bright_16levels = 1;
-
 	/*
 	 * Check for module parameter bogosity, note that we
 	 * init brightness_mode to TPACPI_BRGHT_MODE_MAX in order to be
@@ -6292,12 +6322,9 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
 	if (tpacpi_brightness_get_raw(&b) < 0)
 		return 1;
 
-	if (tp_features.bright_16levels)
-		printk(TPACPI_INFO
-		       "detected a 16-level brightness capable ThinkPad\n");
-
 	memset(&props, 0, sizeof(struct backlight_properties));
-	props.max_brightness = (tp_features.bright_16levels) ? 15 : 7;
+	props.max_brightness = bright_maxlvl;
+	props.brightness = b & TP_EC_BACKLIGHT_LVLMSK;
 	ibm_backlight_device = backlight_device_register(TPACPI_BACKLIGHT_DEV_NAME,
 							 NULL, NULL,
 							 &ibm_backlight_data,
@@ -6320,7 +6347,6 @@ static int __init brightness_init(struct ibm_init_struct *iibm)
 			"or not on your ThinkPad\n", TPACPI_MAIL);
 	}
 
-	ibm_backlight_device->props.brightness = b & TP_EC_BACKLIGHT_LVLMSK;
 	backlight_update_status(ibm_backlight_device);
 
 	vdbg_printk(TPACPI_DBG_INIT | TPACPI_DBG_BRGHT,
@@ -6363,9 +6389,8 @@ static int brightness_read(struct seq_file *m)
 	} else {
 		seq_printf(m, "level:\t\t%d\n", level);
 		seq_printf(m, "commands:\tup, down\n");
-		seq_printf(m, "commands:\tlevel <level>"
-			       " (<level> is 0-%d)\n",
-			       (tp_features.bright_16levels) ? 15 : 7);
+		seq_printf(m, "commands:\tlevel <level> (<level> is 0-%d)\n",
+			       bright_maxlvl);
 	}
 
 	return 0;
@@ -6376,7 +6401,6 @@ static int brightness_write(char *buf)
 	int level;
 	int rc;
 	char *cmd;
-	int max_level = (tp_features.bright_16levels) ? 15 : 7;
 
 	level = brightness_get(NULL);
 	if (level < 0)
@@ -6384,13 +6408,13 @@ static int brightness_write(char *buf)
 
 	while ((cmd = next_cmd(&buf))) {
 		if (strlencmp(cmd, "up") == 0) {
-			if (level < max_level)
+			if (level < bright_maxlvl)
 				level++;
 		} else if (strlencmp(cmd, "down") == 0) {
 			if (level > 0)
 				level--;
 		} else if (sscanf(cmd, "level %d", &level) == 1 &&
-			   level >= 0 && level <= max_level) {
+			   level >= 0 && level <= bright_maxlvl) {
 			/* new level set */
 		} else
 			return -EINVAL;
@@ -9130,6 +9154,11 @@ static int __init thinkpad_acpi_module_init(void)
 		tpacpi_inputdev->id.version = TPACPI_HKEY_INPUT_VERSION;
 		tpacpi_inputdev->dev.parent = &tpacpi_pdev->dev;
 	}
+
+	/* Init subdriver dependencies */
+	tpacpi_detect_brightness_capabilities();
+
+	/* Init subdrivers */
 	for (i = 0; i < ARRAY_SIZE(ibms_init); i++) {
 		ret = ibm_init(&ibms_init[i]);
 		if (ret >= 0 && *ibms_init[i].param)