From 8acb025085aa88c41063bfa0f2c3b4d0a3f2ef11 Mon Sep 17 00:00:00 2001 From: Holger Macht Date: Fri, 20 Oct 2006 14:30:28 -0700 Subject: ACPI: ibm_acpi: Add support for the generic backlight device Add support for the generic backlight interface below /sys/class/backlight. The patch keeps the procfs brightness handling for backward compatibility. Add two generic functions brightness_get and brightness_set to be used both by the procfs related and the sysfs related methods. [apw@shadowen.org: backlight users need to select BACKLIGHT_CLASS_DEVICE] Signed-off-by: Holger Macht Signed-off-by: Andy Whitcroft Signed-off-by: Andrew Morton Signed-off-by: Len Brown --- drivers/acpi/Kconfig | 1 + drivers/acpi/ibm_acpi.c | 75 ++++++++++++++++++++++++++++++++++++++++--------- 2 files changed, 62 insertions(+), 14 deletions(-) diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 0f9d4be7ed7..bc58a3b18e0 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -200,6 +200,7 @@ config ACPI_ASUS config ACPI_IBM tristate "IBM ThinkPad Laptop Extras" depends on X86 + select BACKLIGHT_CLASS_DEVICE ---help--- This is a Linux ACPI driver for the IBM ThinkPad laptops. It adds support for Fn-Fx key combinations, Bluetooth control, video diff --git a/drivers/acpi/ibm_acpi.c b/drivers/acpi/ibm_acpi.c index 003a9876c96..cd8722e4157 100644 --- a/drivers/acpi/ibm_acpi.c +++ b/drivers/acpi/ibm_acpi.c @@ -78,6 +78,7 @@ #include #include #include +#include #include #include @@ -243,6 +244,8 @@ struct ibm_struct { static struct proc_dir_entry *proc_dir = NULL; +static struct backlight_device *ibm_backlight_device; + #define onoff(status,bit) ((status) & (1 << (bit)) ? "on" : "off") #define enabled(status,bit) ((status) & (1 << (bit)) ? "enabled" : "disabled") #define strlencmp(a,b) (strncmp((a), (b), strlen(b))) @@ -1381,12 +1384,22 @@ static int ecdump_write(char *buf) static int brightness_offset = 0x31; +static int brightness_get(struct backlight_device *bd) +{ + u8 level; + if (!acpi_ec_read(brightness_offset, &level)) + return -EIO; + + level &= 0x7; + return level; +} + static int brightness_read(char *p) { int len = 0; - u8 level; + int level; - if (!acpi_ec_read(brightness_offset, &level)) { + 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); @@ -1401,16 +1414,34 @@ static int brightness_read(char *p) #define BRIGHTNESS_UP 4 #define BRIGHTNESS_DOWN 5 -static int brightness_write(char *buf) +static int brightness_set(int value) { int cmos_cmd, inc, i; - u8 level; + int current_value = brightness_get(NULL); + + value &= 7; + + cmos_cmd = value > current_value ? BRIGHTNESS_UP : BRIGHTNESS_DOWN; + inc = value > current_value ? 1 : -1; + for (i = current_value; i != value; i += inc) { + if (!cmos_eval(cmos_cmd)) + return -EIO; + if (!acpi_ec_write(brightness_offset, i + inc)) + return -EIO; + } + + return 0; +} + +static int brightness_write(char *buf) +{ + int level; int new_level; char *cmd; while ((cmd = next_cmd(&buf))) { - if (!acpi_ec_read(brightness_offset, &level)) - return -EIO; + if ((level = brightness_get(NULL)) < 0) + return level; level &= 7; if (strlencmp(cmd, "up") == 0) { @@ -1423,19 +1454,17 @@ static int brightness_write(char *buf) } else return -EINVAL; - cmos_cmd = new_level > level ? BRIGHTNESS_UP : BRIGHTNESS_DOWN; - inc = new_level > level ? 1 : -1; - for (i = level; i != new_level; i += inc) { - if (!cmos_eval(cmos_cmd)) - return -EIO; - if (!acpi_ec_write(brightness_offset, i + inc)) - return -EIO; - } + brightness_set(new_level); } return 0; } +static int brightness_update_status(struct backlight_device *bd) +{ + return brightness_set(bd->props->brightness); +} + static int volume_offset = 0x30; static int volume_read(char *p) @@ -1963,10 +1992,20 @@ IBM_PARAM(brightness); IBM_PARAM(volume); IBM_PARAM(fan); +static struct backlight_properties ibm_backlight_data = { + .owner = THIS_MODULE, + .get_brightness = brightness_get, + .update_status = brightness_update_status, + .max_brightness = 7, +}; + static void acpi_ibm_exit(void) { int i; + if (ibm_backlight_device) + backlight_device_unregister(ibm_backlight_device); + for (i = ARRAY_SIZE(ibms) - 1; i >= 0; i--) ibm_exit(&ibms[i]); @@ -2034,6 +2073,14 @@ static int __init acpi_ibm_init(void) } } + ibm_backlight_device = backlight_device_register("ibm", NULL, + &ibm_backlight_data); + if (IS_ERR(ibm_backlight_device)) { + printk(IBM_ERR "Could not register ibm backlight device\n"); + ibm_backlight_device = NULL; + acpi_ibm_exit(); + } + return 0; } -- cgit v1.2.3