diff options
Diffstat (limited to 'drivers/misc/thinkpad_acpi.c')
| -rw-r--r-- | drivers/misc/thinkpad_acpi.c | 62 |
1 files changed, 53 insertions, 9 deletions
diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c index 99500af651c1..5318eb272c61 100644 --- a/drivers/misc/thinkpad_acpi.c +++ b/drivers/misc/thinkpad_acpi.c @@ -2953,9 +2953,22 @@ static int __init brightness_init(struct ibm_init_struct *iibm) vdbg_printk(TPACPI_DBG_INIT, "initializing brightness subdriver\n"); + if (!brightness_mode) { + if (thinkpad_id.vendor == PCI_VENDOR_ID_LENOVO) + brightness_mode = 2; + else + brightness_mode = 3; + + dbg_printk(TPACPI_DBG_INIT, "selected brightness_mode=%d\n", + brightness_mode); + } + + if (brightness_mode > 3) + return -EINVAL; + b = brightness_get(NULL); if (b < 0) - return b; + return 1; ibm_backlight_device = backlight_device_register( TPACPI_BACKLIGHT_DEV_NAME, NULL, NULL, @@ -2991,13 +3004,35 @@ static int brightness_update_status(struct backlight_device *bd) bd->props.brightness : 0); } +/* + * ThinkPads can read brightness from two places: EC 0x31, or + * CMOS NVRAM byte 0x5E, bits 0-3. + */ static int brightness_get(struct backlight_device *bd) { - u8 level; - if (!acpi_ec_read(brightness_offset, &level)) - return -EIO; + u8 lec = 0, lcmos = 0, level = 0; - level &= 0x7; + if (brightness_mode & 1) { + if (!acpi_ec_read(brightness_offset, &lec)) + return -EIO; + lec &= 7; + level = lec; + }; + if (brightness_mode & 2) { + lcmos = (nvram_read_byte(TP_NVRAM_ADDR_BRIGHTNESS) + & TP_NVRAM_MASK_LEVEL_BRIGHTNESS) + >> TP_NVRAM_POS_LEVEL_BRIGHTNESS; + level = lcmos; + } + + if (brightness_mode == 3 && lec != lcmos) { + printk(IBM_ERR + "CMOS NVRAM (%u) and EC (%u) do not agree " + "on display brightness level\n", + (unsigned int) lcmos, + (unsigned int) lec); + return -EIO; + } return level; } @@ -3007,14 +3042,20 @@ static int brightness_set(int value) int cmos_cmd, inc, i; int current_value = brightness_get(NULL); - value &= 7; + if (value > 7) + return -EINVAL; - cmos_cmd = value > current_value ? TP_CMOS_BRIGHTNESS_UP : TP_CMOS_BRIGHTNESS_DOWN; + 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)) + if ((brightness_mode & 2) && + issue_thinkpad_cmos_command(cmos_cmd)) return -EIO; - if (!acpi_ec_write(brightness_offset, i + inc)) + if ((brightness_mode & 1) && + !acpi_ec_write(brightness_offset, i + inc)) return -EIO; } @@ -4485,6 +4526,9 @@ module_param(force_load, bool, 0); static int fan_control_allowed; module_param_named(fan_control, fan_control_allowed, bool, 0); +static int brightness_mode; +module_param_named(brightness_mode, brightness_mode, int, 0); + #define IBM_PARAM(feature) \ module_param_call(feature, set_ibm_param, NULL, NULL, 0) |