diff options
| -rw-r--r-- | Documentation/laptops/thinkpad-acpi.txt | 12 | ||||
| -rw-r--r-- | drivers/platform/x86/thinkpad_acpi.c | 317 |
2 files changed, 227 insertions, 102 deletions
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index 25ed43d..3d76507 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt @@ -1157,10 +1157,15 @@ 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 +EC and UCMS (or 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 auto-detect which interface to use. +brightness_mode=2 selects UCMS mode, brightness_mode=3 selects EC +mode with NVRAM backing (so that brightness changes are remembered +across shutdown/reboot). + +The driver tries to select which interface to use from a table of +defaults for each ThinkPad model. If it makes a wrong choice, please +report this as a bug, so that we can fix it. When display backlight brightness controls are available through the standard ACPI interface, it is best to use it instead of this direct @@ -1498,6 +1503,7 @@ to enable more than one output class, just add their values. (bluetooth, WWAN, UWB...) 0x0008 HKEY event interface, hotkeys 0x0010 Fan control + 0x0020 Backlight brightness There is also a kernel build option to enable more debugging information, which may be necessary to debug driver problems. diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c index 4eec7703..ba3682c 100644 --- a/drivers/platform/x86/thinkpad_acpi.c +++ b/drivers/platform/x86/thinkpad_acpi.c @@ -192,6 +192,7 @@ enum { #define TPACPI_DBG_RFKILL 0x0004 #define TPACPI_DBG_HKEY 0x0008 #define TPACPI_DBG_FAN 0x0010 +#define TPACPI_DBG_BRGHT 0x0020 #define onoff(status, bit) ((status) & (1 << (bit)) ? "on" : "off") #define enabled(status, bit) ((status) & (1 << (bit)) ? "enabled" : "disabled") @@ -274,7 +275,6 @@ static struct { static struct { u16 hotkey_mask_ff:1; - u16 bright_cmos_ec_unsync:1; } tp_warned; struct thinkpad_id_data { @@ -5526,6 +5526,20 @@ static struct ibm_struct ecdump_driver_data = { #define TPACPI_BACKLIGHT_DEV_NAME "thinkpad_screen" +/* + * ThinkPads can read brightness from two places: EC HBRV (0x31), or + * CMOS NVRAM byte 0x5E, bits 0-3. + * + * EC HBRV (0x31) has the following layout + * Bit 7: unknown function + * Bit 6: unknown function + * Bit 5: Z: honour scale changes, NZ: ignore scale changes + * Bit 4: must be set to zero to avoid problems + * Bit 3-0: backlight brightness level + * + * brightness_get_raw returns status data in the HBRV layout + */ + enum { TP_EC_BACKLIGHT = 0x31, @@ -5535,108 +5549,164 @@ enum { TP_EC_BACKLIGHT_MAPSW = 0x20, }; +enum tpacpi_brightness_access_mode { + TPACPI_BRGHT_MODE_AUTO = 0, /* Not implemented yet */ + TPACPI_BRGHT_MODE_EC, /* EC control */ + TPACPI_BRGHT_MODE_UCMS_STEP, /* UCMS step-based control */ + TPACPI_BRGHT_MODE_ECNVRAM, /* EC control w/ NVRAM store */ + TPACPI_BRGHT_MODE_MAX +}; + static struct backlight_device *ibm_backlight_device; -static int brightness_mode; + +static enum tpacpi_brightness_access_mode brightness_mode = + TPACPI_BRGHT_MODE_MAX; + static unsigned int brightness_enable = 2; /* 2 = auto, 0 = no, 1 = yes */ static struct mutex brightness_mutex; -/* - * ThinkPads can read brightness from two places: EC 0x31, or - * CMOS NVRAM byte 0x5E, bits 0-3. - * - * EC 0x31 has the following layout - * Bit 7: unknown function - * Bit 6: unknown function - * Bit 5: Z: honour scale changes, NZ: ignore scale changes - * Bit 4: must be set to zero to avoid problems - * Bit 3-0: backlight brightness level - * - * brightness_get_raw returns status data in the EC 0x31 layout - */ -static int brightness_get_raw(int *status) +/* NVRAM brightness access, + * call with brightness_mutex held! */ +static unsigned int tpacpi_brightness_nvram_get(void) { - u8 lec = 0, lcmos = 0, level = 0; + u8 lnvram; - if (brightness_mode & 1) { - if (!acpi_ec_read(TP_EC_BACKLIGHT, &lec)) - return -EIO; - level = lec & TP_EC_BACKLIGHT_LVLMSK; - }; - 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; - } - - if (brightness_mode == 3) { - *status = lec; /* Prefer EC, CMOS is just a backing store */ - lec &= TP_EC_BACKLIGHT_LVLMSK; - if (lec == lcmos) - tp_warned.bright_cmos_ec_unsync = 0; - else { - if (!tp_warned.bright_cmos_ec_unsync) { - printk(TPACPI_ERR - "CMOS NVRAM (%u) and EC (%u) do not " - "agree on display brightness level\n", - (unsigned int) lcmos, - (unsigned int) lec); - tp_warned.bright_cmos_ec_unsync = 1; - } + 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; + + return lnvram; +} + +static void tpacpi_brightness_checkpoint_nvram(void) +{ + u8 lec = 0; + u8 b_nvram; + + if (brightness_mode != TPACPI_BRGHT_MODE_ECNVRAM) + return; + + vdbg_printk(TPACPI_DBG_BRGHT, + "trying to checkpoint backlight level to NVRAM...\n"); + + if (mutex_lock_killable(&brightness_mutex) < 0) + return; + + if (unlikely(!acpi_ec_read(TP_EC_BACKLIGHT, &lec))) + goto unlock; + lec &= TP_EC_BACKLIGHT_LVLMSK; + b_nvram = nvram_read_byte(TP_NVRAM_ADDR_BRIGHTNESS); + + if (lec != ((b_nvram & TP_NVRAM_MASK_LEVEL_BRIGHTNESS) + >> TP_NVRAM_POS_LEVEL_BRIGHTNESS)) { + /* NVRAM needs update */ + b_nvram &= ~(TP_NVRAM_MASK_LEVEL_BRIGHTNESS << + TP_NVRAM_POS_LEVEL_BRIGHTNESS); + b_nvram |= lec; + nvram_write_byte(b_nvram, TP_NVRAM_ADDR_BRIGHTNESS); + dbg_printk(TPACPI_DBG_BRGHT, + "updated NVRAM backlight level to %u (0x%02x)\n", + (unsigned int) lec, (unsigned int) b_nvram); + } else + vdbg_printk(TPACPI_DBG_BRGHT, + "NVRAM backlight level already is %u (0x%02x)\n", + (unsigned int) lec, (unsigned int) b_nvram); + +unlock: + mutex_unlock(&brightness_mutex); +} + + +/* call with brightness_mutex held! */ +static int tpacpi_brightness_get_raw(int *status) +{ + u8 lec = 0; + + switch (brightness_mode) { + case TPACPI_BRGHT_MODE_UCMS_STEP: + *status = tpacpi_brightness_nvram_get(); + return 0; + case TPACPI_BRGHT_MODE_EC: + case TPACPI_BRGHT_MODE_ECNVRAM: + if (unlikely(!acpi_ec_read(TP_EC_BACKLIGHT, &lec))) return -EIO; - } - } else { - *status = level; + *status = lec; + return 0; + default: + return -ENXIO; } +} + +/* call with brightness_mutex held! */ +/* do NOT call with illegal backlight level value */ +static int tpacpi_brightness_set_ec(unsigned int value) +{ + u8 lec = 0; + + if (unlikely(!acpi_ec_read(TP_EC_BACKLIGHT, &lec))) + return -EIO; + + if (unlikely(!acpi_ec_write(TP_EC_BACKLIGHT, + (lec & TP_EC_BACKLIGHT_CMDMSK) | + (value & TP_EC_BACKLIGHT_LVLMSK)))) + return -EIO; + + return 0; +} + +/* call with brightness_mutex held! */ +static int tpacpi_brightness_set_ucmsstep(unsigned int value) +{ + int cmos_cmd, inc; + unsigned int current_value, i; + + current_value = tpacpi_brightness_nvram_get(); + + if (value == current_value) + return 0; + + cmos_cmd = (value > current_value) ? + TP_CMOS_BRIGHTNESS_UP : + TP_CMOS_BRIGHTNESS_DOWN; + inc = (value > current_value) ? 1 : -1; + + for (i = current_value; i != value; i += inc) + if (issue_thinkpad_cmos_command(cmos_cmd)) + return -EIO; return 0; } /* May return EINTR which can always be mapped to ERESTARTSYS */ -static int brightness_set(int value) +static int brightness_set(unsigned int value) { - int cmos_cmd, inc, i, res; - int current_value; - int command_bits; + int res; if (value > ((tp_features.bright_16levels)? 15 : 7) || value < 0) return -EINVAL; + vdbg_printk(TPACPI_DBG_BRGHT, + "set backlight level to %d\n", value); + res = mutex_lock_killable(&brightness_mutex); if (res < 0) return res; - res = brightness_get_raw(¤t_value); - if (res < 0) - goto errout; - - command_bits = current_value & TP_EC_BACKLIGHT_CMDMSK; - current_value &= TP_EC_BACKLIGHT_LVLMSK; - - cmos_cmd = value > current_value ? - TP_CMOS_BRIGHTNESS_UP : - TP_CMOS_BRIGHTNESS_DOWN; - inc = (value > current_value)? 1 : -1; - - res = 0; - for (i = current_value; i != value; i += inc) { - if ((brightness_mode & 2) && - issue_thinkpad_cmos_command(cmos_cmd)) { - res = -EIO; - goto errout; - } - if ((brightness_mode & 1) && - !acpi_ec_write(TP_EC_BACKLIGHT, - (i + inc) | command_bits)) { - res = -EIO; - goto errout;; - } + switch (brightness_mode) { + case TPACPI_BRGHT_MODE_EC: + case TPACPI_BRGHT_MODE_ECNVRAM: + res = tpacpi_brightness_set_ec(value); + break; + case TPACPI_BRGHT_MODE_UCMS_STEP: + res = tpacpi_brightness_set_ucmsstep(value); + break; + default: + res = -ENXIO; } -errout: mutex_unlock(&brightness_mutex); return res; } @@ -5645,21 +5715,34 @@ errout: 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( + unsigned int level = (bd->props.fb_blank == FB_BLANK_UNBLANK && bd->props.power == FB_BLANK_UNBLANK) ? - bd->props.brightness : 0); + bd->props.brightness : 0; + + dbg_printk(TPACPI_DBG_BRGHT, + "backlight: attempt to set level to %d\n", + level); + + /* it is the backlight class's job (caller) to handle + * EINTR and other errors properly */ + return brightness_set(level); } static int brightness_get(struct backlight_device *bd) { int status, res; - res = brightness_get_raw(&status); + res = mutex_lock_killable(&brightness_mutex); if (res < 0) - return 0; /* FIXME: teach backlight about error handling */ + return 0; + + res = tpacpi_brightness_get_raw(&status); + + mutex_unlock(&brightness_mutex); + + if (res < 0) + return 0; return status & TP_EC_BACKLIGHT_LVLMSK; } @@ -5709,7 +5792,7 @@ static int __init brightness_init(struct ibm_init_struct *iibm) } if (!brightness_enable) { - dbg_printk(TPACPI_DBG_INIT, + dbg_printk(TPACPI_DBG_INIT | TPACPI_DBG_BRGHT, "brightness support disabled by " "module parameter\n"); return 1; @@ -5724,20 +5807,38 @@ static int __init brightness_init(struct ibm_init_struct *iibm) if (b == 16) tp_features.bright_16levels = 1; - if (!brightness_mode) { - if (thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO) - brightness_mode = 2; - else - brightness_mode = 3; + /* + * Check for module parameter bogosity, note that we + * init brightness_mode to TPACPI_BRGHT_MODE_MAX in order to be + * able to detect "unspecified" + */ + if (brightness_mode > TPACPI_BRGHT_MODE_MAX) + return -EINVAL; - dbg_printk(TPACPI_DBG_INIT, "selected brightness_mode=%d\n", - brightness_mode); - } + /* TPACPI_BRGHT_MODE_AUTO not implemented yet, just use default */ + if (brightness_mode == TPACPI_BRGHT_MODE_AUTO || + brightness_mode == TPACPI_BRGHT_MODE_MAX) { + if (thinkpad_id.vendor == PCI_VENDOR_ID_IBM) { + /* + * IBM models that define HBRV probably have + * EC-based backlight level control + */ + if (acpi_evalf(ec_handle, NULL, "HBRV", "qd")) + /* T40-T43, R50-R52, R50e, R51e, X31-X41 */ + brightness_mode = TPACPI_BRGHT_MODE_ECNVRAM; + else + /* all other IBM ThinkPads */ + brightness_mode = TPACPI_BRGHT_MODE_UCMS_STEP; + } else + /* All Lenovo ThinkPads */ + brightness_mode = TPACPI_BRGHT_MODE_UCMS_STEP; - if (brightness_mode > 3) - return -EINVAL; + dbg_printk(TPACPI_DBG_BRGHT, + "selected brightness_mode=%d\n", + brightness_mode); + } - if (brightness_get_raw(&b) < 0) + if (tpacpi_brightness_get_raw(&b) < 0) return 1; if (tp_features.bright_16levels) @@ -5751,7 +5852,8 @@ static int __init brightness_init(struct ibm_init_struct *iibm) printk(TPACPI_ERR "Could not register backlight device\n"); return PTR_ERR(ibm_backlight_device); } - vdbg_printk(TPACPI_DBG_INIT, "brightness is supported\n"); + vdbg_printk(TPACPI_DBG_INIT | TPACPI_DBG_BRGHT, + "brightness is supported\n"); ibm_backlight_device->props.max_brightness = (tp_features.bright_16levels)? 15 : 7; @@ -5761,13 +5863,25 @@ static int __init brightness_init(struct ibm_init_struct *iibm) return 0; } +static void brightness_suspend(pm_message_t state) +{ + tpacpi_brightness_checkpoint_nvram(); +} + +static void brightness_shutdown(void) +{ + tpacpi_brightness_checkpoint_nvram(); +} + static void brightness_exit(void) { if (ibm_backlight_device) { - vdbg_printk(TPACPI_DBG_EXIT, + vdbg_printk(TPACPI_DBG_EXIT | TPACPI_DBG_BRGHT, "calling backlight_device_unregister()\n"); backlight_device_unregister(ibm_backlight_device); } + + tpacpi_brightness_checkpoint_nvram(); } static int brightness_read(char *p) @@ -5814,6 +5928,9 @@ static int brightness_write(char *buf) return -EINVAL; } + tpacpi_disclose_usertask("procfs brightness", + "set level to %d\n", level); + /* * 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 @@ -5827,6 +5944,8 @@ static struct ibm_struct brightness_driver_data = { .read = brightness_read, .write = brightness_write, .exit = brightness_exit, + .suspend = brightness_suspend, + .shutdown = brightness_shutdown, }; /************************************************************************* @@ -7465,10 +7584,10 @@ module_param_named(fan_control, fan_control_allowed, bool, 0); MODULE_PARM_DESC(fan_control, "Enables setting fan parameters features when true"); -module_param_named(brightness_mode, brightness_mode, int, 0); +module_param_named(brightness_mode, brightness_mode, uint, 0); MODULE_PARM_DESC(brightness_mode, "Selects brightness control strategy: " - "0=auto, 1=EC, 2=CMOS, 3=both"); + "0=auto, 1=EC, 2=UCMS, 3=EC+NVRAM"); module_param(brightness_enable, uint, 0); MODULE_PARM_DESC(brightness_enable, |