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)