toshiba_acpi: Add support for transflective LCD
Some Toshiba laptops have the transflective LCD and toshset
can control its backlight state. I brought this feature to the
mainline. To support transflective LCD, it's implemented by
adding an extra level to the backlight and having 0 change to
transflective mode. It was tested on a Toshiba Portege R500.
Signed-off-by: Akio Idehara <zbe64533@gmail.com>
Signed-off-by: Matthew Garrett <mjg@redhat.com>
diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 1bb128b..f88b9d2 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -95,6 +95,7 @@
/* registers */
#define HCI_FAN 0x0004
+#define HCI_TR_BACKLIGHT 0x0005
#define HCI_SYSTEM_EVENT 0x0016
#define HCI_VIDEO_OUT 0x001c
#define HCI_HOTKEY_EVENT 0x001e
@@ -134,6 +135,7 @@
unsigned int system_event_supported:1;
unsigned int ntfy_supported:1;
unsigned int info_supported:1;
+ unsigned int tr_backlight_supported:1;
struct mutex mutex;
};
@@ -478,16 +480,46 @@
.poll = bt_rfkill_poll,
};
+static int get_tr_backlight_status(struct toshiba_acpi_dev *dev, bool *enabled)
+{
+ u32 hci_result;
+ u32 status;
+
+ hci_read1(dev, HCI_TR_BACKLIGHT, &status, &hci_result);
+ *enabled = !status;
+ return hci_result == HCI_SUCCESS ? 0 : -EIO;
+}
+
+static int set_tr_backlight_status(struct toshiba_acpi_dev *dev, bool enable)
+{
+ u32 hci_result;
+ u32 value = !enable;
+
+ hci_write1(dev, HCI_TR_BACKLIGHT, value, &hci_result);
+ return hci_result == HCI_SUCCESS ? 0 : -EIO;
+}
+
static struct proc_dir_entry *toshiba_proc_dir /*= 0*/ ;
static int __get_lcd_brightness(struct toshiba_acpi_dev *dev)
{
u32 hci_result;
u32 value;
+ int brightness = 0;
+
+ if (dev->tr_backlight_supported) {
+ bool enabled;
+ int ret = get_tr_backlight_status(dev, &enabled);
+ if (ret)
+ return ret;
+ if (enabled)
+ return 0;
+ brightness++;
+ }
hci_read1(dev, HCI_LCD_BRIGHTNESS, &value, &hci_result);
if (hci_result == HCI_SUCCESS)
- return (value >> HCI_LCD_BRIGHTNESS_SHIFT);
+ return brightness + (value >> HCI_LCD_BRIGHTNESS_SHIFT);
return -EIO;
}
@@ -502,15 +534,16 @@
{
struct toshiba_acpi_dev *dev = m->private;
int value;
+ int levels;
if (!dev->backlight_dev)
return -ENODEV;
+ levels = dev->backlight_dev->props.max_brightness + 1;
value = get_lcd_brightness(dev->backlight_dev);
if (value >= 0) {
seq_printf(m, "brightness: %d\n", value);
- seq_printf(m, "brightness_levels: %d\n",
- HCI_LCD_BRIGHTNESS_LEVELS);
+ seq_printf(m, "brightness_levels: %d\n", levels);
return 0;
}
@@ -527,6 +560,15 @@
{
u32 hci_result;
+ if (dev->tr_backlight_supported) {
+ bool enable = !value;
+ int ret = set_tr_backlight_status(dev, enable);
+ if (ret)
+ return ret;
+ if (value)
+ value--;
+ }
+
value = value << HCI_LCD_BRIGHTNESS_SHIFT;
hci_write1(dev, HCI_LCD_BRIGHTNESS, value, &hci_result);
return hci_result == HCI_SUCCESS ? 0 : -EIO;
@@ -546,6 +588,7 @@
size_t len;
int value;
int ret;
+ int levels = dev->backlight_dev->props.max_brightness + 1;
len = min(count, sizeof(cmd) - 1);
if (copy_from_user(cmd, buf, len))
@@ -553,7 +596,7 @@
cmd[len] = '\0';
if (sscanf(cmd, " brightness : %i", &value) == 1 &&
- value >= 0 && value < HCI_LCD_BRIGHTNESS_LEVELS) {
+ value >= 0 && value < levels) {
ret = set_lcd_brightness(dev, value);
if (ret == 0)
ret = count;
@@ -865,6 +908,7 @@
}
static const struct backlight_ops toshiba_backlight_data = {
+ .options = BL_CORE_SUSPENDRESUME,
.get_brightness = get_lcd_brightness,
.update_status = set_lcd_status,
};
@@ -1030,6 +1074,7 @@
struct backlight_properties props;
int brightness;
int ret;
+ bool enabled;
/*
* Some machines don't support the backlight methods at all, and
@@ -1046,10 +1091,18 @@
return 0;
}
+ /* Determine whether or not BIOS supports transflective backlight */
+ ret = get_tr_backlight_status(dev, &enabled);
+ dev->tr_backlight_supported = !ret;
+
props.type = BACKLIGHT_PLATFORM;
props.max_brightness = HCI_LCD_BRIGHTNESS_LEVELS - 1;
memset(&props, 0, sizeof(props));
+ /* adding an extra level and having 0 change to transflective mode */
+ if (dev->tr_backlight_supported)
+ props.max_brightness++;
+
dev->backlight_dev = backlight_device_register("toshiba",
&dev->acpi_dev->dev,
dev,