ThinkPad ACPI Extras Driver
- Version 0.16
- August 2nd, 2007
+ Version 0.17
+ October 04th, 2007
Borislav Deianov <borislav@users.sf.net>
Henrique de Moraes Holschuh <hmh@hmh.eng.br>
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. The driver will disable its native
+backlight brightness control interface if it detects that the standard
+ACPI interface is available in the ThinkPad.
+
+The brightness_enable module parameter can be used to control whether
+the LCD brightness control feature will be enabled when available.
+brightness_enable=0 forces it to be disabled. brightness_enable=1
+forces it to be enabled when available, even if the standard ACPI
+interface is also available.
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.
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
* 02110-1301, USA.
*/
-#define IBM_VERSION "0.16"
+#define IBM_VERSION "0.17"
#define TPACPI_SYSFS_VERSION 0x020000
/*
KEY_UNKNOWN, /* 0x0C: FN+BACKSPACE */
KEY_UNKNOWN, /* 0x0D: FN+INSERT */
KEY_UNKNOWN, /* 0x0E: FN+DELETE */
- KEY_BRIGHTNESSUP, /* 0x0F: FN+HOME (brightness up) */
+ KEY_RESERVED, /* 0x0F: FN+HOME (brightness up) */
/* Scan codes 0x10 to 0x1F: Extended ACPI HKEY hot keys */
- KEY_BRIGHTNESSDOWN, /* 0x10: FN+END (brightness down) */
+ KEY_RESERVED, /* 0x10: FN+END (brightness down) */
KEY_RESERVED, /* 0x11: FN+PGUP (thinklight toggle) */
KEY_UNKNOWN, /* 0x12: FN+PGDOWN */
KEY_ZOOM, /* 0x13: FN+SPACE (zoom) */
- KEY_VOLUMEUP, /* 0x14: VOLUME UP */
- KEY_VOLUMEDOWN, /* 0x15: VOLUME DOWN */
- KEY_MUTE, /* 0x16: MUTE */
+ KEY_RESERVED, /* 0x14: VOLUME UP */
+ KEY_RESERVED, /* 0x15: VOLUME DOWN */
+ KEY_RESERVED, /* 0x16: MUTE */
KEY_VENDOR, /* 0x17: Thinkpad/AccessIBM/Lenovo */
/* (assignments unknown, please report if found) */
KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
KEY_RESERVED, /* 0x11: FN+PGUP (thinklight toggle) */
KEY_UNKNOWN, /* 0x12: FN+PGDOWN */
KEY_ZOOM, /* 0x13: FN+SPACE (zoom) */
- KEY_VOLUMEUP, /* 0x14: VOLUME UP */
- KEY_VOLUMEDOWN, /* 0x15: VOLUME DOWN */
- KEY_MUTE, /* 0x16: MUTE */
+ KEY_RESERVED, /* 0x14: VOLUME UP */
+ KEY_RESERVED, /* 0x15: VOLUME DOWN */
+ KEY_RESERVED, /* 0x16: MUTE */
KEY_VENDOR, /* 0x17: Thinkpad/AccessIBM/Lenovo */
/* (assignments unknown, please report if found) */
KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN, KEY_UNKNOWN,
return len;
}
- res = mutex_lock_interruptible(&hotkey_mutex);
- if (res < 0)
- return res;
+ if (mutex_lock_interruptible(&hotkey_mutex))
+ return -ERESTARTSYS;
res = hotkey_get(&status, &mask);
mutex_unlock(&hotkey_mutex);
if (res)
if (!tp_features.hotkey)
return -ENODEV;
- res = mutex_lock_interruptible(&hotkey_mutex);
- if (res < 0)
- return res;
+ if (mutex_lock_interruptible(&hotkey_mutex))
+ return -ERESTARTSYS;
res = hotkey_get(&status, &mask);
if (res)
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 acpi_status __init brightness_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)) {
+ *rv = handle;
+ return AE_CTRL_TERMINATE;
+ } else {
+ return AE_OK;
+ }
+}
+
+static int __init brightness_check_std_acpi_support(void)
+{
+ int status;
+ void *found_node = NULL;
+
+ if (!vid_handle) {
+ IBM_ACPIHANDLE_INIT(vid);
+ }
+ if (!vid_handle)
+ return 0;
+
+ /* Search for a _BCL method, but don't execute it */
+ status = acpi_walk_namespace(ACPI_TYPE_METHOD, vid_handle, 3,
+ brightness_find_bcl, NULL, &found_node);
+
+ return (ACPI_SUCCESS(status) && found_node != NULL);
+}
+
static int __init brightness_init(struct ibm_init_struct *iibm)
{
int b;
mutex_init(&brightness_mutex);
+ if (!brightness_enable) {
+ dbg_printk(TPACPI_DBG_INIT,
+ "brightness support disabled by module parameter\n");
+ return 1;
+ } else if (brightness_enable > 1) {
+ if (brightness_check_std_acpi_support()) {
+ printk(IBM_NOTICE
+ "standard ACPI backlight interface available, not loading native one...\n");
+ return 1;
+ }
+ }
+
if (!brightness_mode) {
if (thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO)
brightness_mode = 2;
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);
}
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);
static int brightness_update_status(struct backlight_device *bd)
{
+ /* it is the backlight class's job (caller) to handle
+ * EINTR and other errors properly */
return brightness_set(
(bd->props.fb_blank == FB_BLANK_UNBLANK &&
bd->props.power == FB_BLANK_UNBLANK) ?
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;
}
return level;
}
+/* May return EINTR which can always be mapped to ERESTARTSYS */
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);
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) {
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;
static int brightness_write(char *buf)
{
int level;
- int new_level;
+ int rc;
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;
+ level = brightness_get(NULL);
+ if (level < 0)
+ return level;
+ while ((cmd = next_cmd(&buf))) {
if (strlencmp(cmd, "up") == 0) {
- new_level = level == 7 ? 7 : level + 1;
+ if (level < max_level)
+ level++;
} else if (strlencmp(cmd, "down") == 0) {
- new_level = level == 0 ? 0 : level - 1;
- } else if (sscanf(cmd, "level %d", &new_level) == 1 &&
- new_level >= 0 && new_level <= 7) {
- /* new_level set */
+ if (level > 0)
+ level--;
+ } else if (sscanf(cmd, "level %d", &level) == 1 &&
+ level >= 0 && level <= max_level) {
+ /* new level set */
} else
return -EINVAL;
-
- brightness_set(new_level);
}
- return 0;
+ /*
+ * Now we know what the final level should be, so we try to set it.
+ * Doing it this way makes the syscall restartable in case of EINTR
+ */
+ rc = brightness_set(level);
+ return (rc == -EINTR)? ERESTARTSYS : rc;
}
static struct ibm_struct brightness_driver_data = {
/* scale down from 0-255 to 0-7 */
newlevel = (s >> 5) & 0x07;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = fan_get_status(&status);
if (!rc && (status &
int rc;
u8 s;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = fan_get_status(&s);
if (!rc)
fan_update_desired_level(s);
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
if (level == TPACPI_FAN_LAST_LEVEL)
level = fan_control_desired_level;
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
switch (fan_control_access_mode) {
case TPACPI_FAN_WR_ACPI_FANS:
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = 0;
switch (fan_control_access_mode) {
if (!fan_control_allowed)
return -EPERM;
- rc = mutex_lock_interruptible(&fan_mutex);
- if (rc < 0)
- return rc;
+ if (mutex_lock_interruptible(&fan_mutex))
+ return -ERESTARTSYS;
rc = 0;
switch (fan_control_access_mode) {
unsigned int i;
struct ibm_struct *ibm;
+ if (!kp || !kp->name || !val)
+ return -EINVAL;
+
for (i = 0; i < ARRAY_SIZE(ibms_init); i++) {
ibm = ibms_init[i].data;
- BUG_ON(ibm == NULL);
+ WARN_ON(ibm == NULL);
+
+ if (!ibm || !ibm->name)
+ continue;
if (strcmp(ibm->name, kp->name) == 0 && ibm->write) {
if (strlen(val) > sizeof(ibms_init[i].param) - 2)
static int brightness_mode;
module_param_named(brightness_mode, brightness_mode, int, 0);
+static unsigned int brightness_enable = 2; /* 2 = auto, 0 = no, 1 = yes */
+module_param(brightness_enable, uint, 0);
+
static unsigned int hotkey_report_mode;
module_param(hotkey_report_mode, uint, 0);
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