diff options
| -rw-r--r-- | Documentation/thinkpad-acpi.txt | 61 | ||||
| -rw-r--r-- | drivers/misc/thinkpad_acpi.c | 91 | ||||
| -rw-r--r-- | drivers/misc/thinkpad_acpi.h | 3 |
3 files changed, 118 insertions, 37 deletions
diff --git a/Documentation/thinkpad-acpi.txt b/Documentation/thinkpad-acpi.txt index ec499265deca..a743bfa62b95 100644 --- a/Documentation/thinkpad-acpi.txt +++ b/Documentation/thinkpad-acpi.txt @@ -923,19 +923,26 @@ sysfs backlight device "thinkpad_screen" This feature allows software control of the LCD brightness on ThinkPad models which don't have a hardware brightness slider. -It has some limitations: the LCD backlight cannot be actually turned on or off -by this interface, and in many ThinkPad models, the "dim while on battery" -functionality will be enabled by the BIOS when this interface is used, and -cannot be controlled. - -The backlight control has eight levels, ranging from 0 to 7. Some of the -levels may not be distinct. - -There are two interfaces to the firmware for brightness control, EC and CMOS. -To select which one should be used, use the brightness_mode module parameter: -brightness_mode=1 selects EC mode, brightness_mode=2 selects CMOS mode, -brightness_mode=3 selects both EC and CMOS. The driver tries to autodetect -which interface to use. +It has some limitations: the LCD backlight cannot be actually turned on or +off by this interface, and in many ThinkPad models, the "dim while on +battery" functionality will be enabled by the BIOS when this interface is +used, and cannot be controlled. + +On IBM (and some of the earlier Lenovo) ThinkPads, the backlight control +has eight brightness levels, ranging from 0 to 7. Some of the levels +may not be distinct. Later Lenovo models that implement the ACPI +display backlight brightness control methods have 16 levels, ranging +from 0 to 15. + +There are two interfaces to the firmware for direct brightness control, +EC and CMOS. To select which one should be used, use the +brightness_mode module parameter: brightness_mode=1 selects EC mode, +brightness_mode=2 selects CMOS mode, brightness_mode=3 selects both EC +and CMOS. The driver tries to autodetect which interface to use. + +When display backlight brightness controls are available through the +standard ACPI interface, it is best to use it instead of this direct +ThinkPad-specific interface. Procfs notes: @@ -947,11 +954,11 @@ Procfs notes: Sysfs notes: -The interface is implemented through the backlight sysfs class, which is poorly -documented at this time. +The interface is implemented through the backlight sysfs class, which is +poorly documented at this time. -Locate the thinkpad_screen device under /sys/class/backlight, and inside it -there will be the following attributes: +Locate the thinkpad_screen device under /sys/class/backlight, and inside +it there will be the following attributes: max_brightness: Reads the maximum brightness the hardware can be set to. @@ -961,17 +968,19 @@ there will be the following attributes: Reads what brightness the screen is set to at this instant. brightness: - Writes request the driver to change brightness to the given - value. Reads will tell you what brightness the driver is trying - to set the display to when "power" is set to zero and the display - has not been dimmed by a kernel power management event. + Writes request the driver to change brightness to the + given value. Reads will tell you what brightness the + driver is trying to set the display to when "power" is set + to zero and the display has not been dimmed by a kernel + power management event. power: - power management mode, where 0 is "display on", and 1 to 3 will - dim the display backlight to brightness level 0 because - thinkpad-acpi cannot really turn the backlight off. Kernel - power management events can temporarily increase the current - power management level, i.e. they can dim the display. + power management mode, where 0 is "display on", and 1 to 3 + will dim the display backlight to brightness level 0 + because thinkpad-acpi cannot really turn the backlight + off. Kernel power management events can temporarily + increase the current power management level, i.e. they can + dim the display. Volume control -- /proc/acpi/ibm/volume diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c index 63b1e2610c60..322ba25b4798 100644 --- a/drivers/misc/thinkpad_acpi.c +++ b/drivers/misc/thinkpad_acpi.c @@ -3114,6 +3114,66 @@ static struct backlight_ops ibm_backlight_data = { static struct mutex brightness_mutex; +static int __init tpacpi_query_bcll_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(IBM_ERR "Unknown BCLL data, " + "please report this to %s\n", IBM_MAIL); + rc = 0; + } else { + rc = obj->package.count; + } + } else { + return 0; + } + + kfree(buffer.pointer); + return rc; +} + +static acpi_status __init brightness_find_bcll(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("BCLL", name, sizeof(name) - 1)) { + if (tpacpi_query_bcll_levels(handle) == 16) { + *rv = handle; + return AE_CTRL_TERMINATE; + } else { + return AE_OK; + } + } else { + return AE_OK; + } +} + +static int __init brightness_check_levels(void) +{ + int status; + void *found_node = NULL; + + if (!vid_handle) { + IBM_ACPIHANDLE_INIT(vid); + } + if (!vid_handle) + return 0; + + /* Search for a BCLL package with 16 levels */ + status = acpi_walk_namespace(ACPI_TYPE_PACKAGE, vid_handle, 3, + brightness_find_bcll, NULL, &found_node); + + return (ACPI_SUCCESS(status) && found_node != NULL); +} + static int __init brightness_init(struct ibm_init_struct *iibm) { int b; @@ -3135,10 +3195,17 @@ static int __init brightness_init(struct ibm_init_struct *iibm) if (brightness_mode > 3) return -EINVAL; + tp_features.bright_16levels = + thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO && + brightness_check_levels(); + b = brightness_get(NULL); if (b < 0) return 1; + if (tp_features.bright_16levels) + printk(IBM_INFO "detected a 16-level brightness capable ThinkPad\n"); + ibm_backlight_device = backlight_device_register( TPACPI_BACKLIGHT_DEV_NAME, NULL, NULL, &ibm_backlight_data); @@ -3148,7 +3215,8 @@ static int __init brightness_init(struct ibm_init_struct *iibm) } vdbg_printk(TPACPI_DBG_INIT, "brightness is supported\n"); - ibm_backlight_device->props.max_brightness = 7; + ibm_backlight_device->props.max_brightness = + (tp_features.bright_16levels)? 15 : 7; ibm_backlight_device->props.brightness = b; backlight_update_status(ibm_backlight_device); @@ -3184,13 +3252,14 @@ static int brightness_get(struct backlight_device *bd) if (brightness_mode & 1) { if (!acpi_ec_read(brightness_offset, &lec)) return -EIO; - lec &= 7; + lec &= (tp_features.bright_16levels)? 0x0f : 0x07; level = lec; }; if (brightness_mode & 2) { lcmos = (nvram_read_byte(TP_NVRAM_ADDR_BRIGHTNESS) & TP_NVRAM_MASK_LEVEL_BRIGHTNESS) >> TP_NVRAM_POS_LEVEL_BRIGHTNESS; + lcmos &= (tp_features.bright_16levels)? 0x0f : 0x07; level = lcmos; } @@ -3211,7 +3280,7 @@ static int brightness_set(int value) int cmos_cmd, inc, i, res; int current_value; - if (value > 7) + if (value > ((tp_features.bright_16levels)? 15 : 7)) return -EINVAL; res = mutex_lock_interruptible(&brightness_mutex); @@ -3227,7 +3296,7 @@ static int brightness_set(int value) cmos_cmd = value > current_value ? TP_CMOS_BRIGHTNESS_UP : TP_CMOS_BRIGHTNESS_DOWN; - inc = value > current_value ? 1 : -1; + inc = (value > current_value)? 1 : -1; res = 0; for (i = current_value; i != value; i += inc) { @@ -3256,10 +3325,11 @@ static int brightness_read(char *p) if ((level = brightness_get(NULL)) < 0) { len += sprintf(p + len, "level:\t\tunreadable\n"); } else { - len += sprintf(p + len, "level:\t\t%d\n", level & 0x7); + len += sprintf(p + len, "level:\t\t%d\n", level); len += sprintf(p + len, "commands:\tup, down\n"); len += sprintf(p + len, "commands:\tlevel <level>" - " (<level> is 0-7)\n"); + " (<level> is 0-%d)\n", + (tp_features.bright_16levels) ? 15 : 7); } return len; @@ -3270,18 +3340,19 @@ static int brightness_write(char *buf) int level; int new_level; char *cmd; + int max_level = (tp_features.bright_16levels) ? 15 : 7; while ((cmd = next_cmd(&buf))) { if ((level = brightness_get(NULL)) < 0) return level; - level &= 7; if (strlencmp(cmd, "up") == 0) { - new_level = level == 7 ? 7 : level + 1; + new_level = level == (max_level)? + max_level : level + 1; } else if (strlencmp(cmd, "down") == 0) { - new_level = level == 0 ? 0 : level - 1; + new_level = level == 0? 0 : level - 1; } else if (sscanf(cmd, "level %d", &new_level) == 1 && - new_level >= 0 && new_level <= 7) { + new_level >= 0 && new_level <= max_level) { /* new_level set */ } else return -EINVAL; diff --git a/drivers/misc/thinkpad_acpi.h b/drivers/misc/thinkpad_acpi.h index 3abcc8120634..8ca19c333727 100644 --- a/drivers/misc/thinkpad_acpi.h +++ b/drivers/misc/thinkpad_acpi.h @@ -84,7 +84,7 @@ /* ThinkPad CMOS NVRAM constants */ #define TP_NVRAM_ADDR_BRIGHTNESS 0x5e -#define TP_NVRAM_MASK_LEVEL_BRIGHTNESS 0x07 +#define TP_NVRAM_MASK_LEVEL_BRIGHTNESS 0x0f #define TP_NVRAM_POS_LEVEL_BRIGHTNESS 0 #define onoff(status,bit) ((status) & (1 << (bit)) ? "on" : "off") @@ -246,6 +246,7 @@ static struct { u32 hotkey_wlsw:1; u32 light:1; u32 light_status:1; + u32 bright_16levels:1; u32 wan:1; u32 fan_ctrl_status_undef:1; u32 input_device_registered:1; |