Currently the backlight device is registered unconditionally, but many
(probably most) Toshibas either don't support HCI_LCD_BRIGHTNESS or only
support reading from it. This patch adds a test of HCI_LCD_BRIGHTNESS
during initialization and only registers the backlight device if this
interface supports both reads and writes.
Cc: Akio Idehara <zbe64533@xxxxxxxxx>
Signed-off-by: Seth Forshee <seth.forshee@xxxxxxxxxxxxx>
---
Matthew,
Please consider applying this as a fix for 3.4.
This is certainly going to conflict with Akio's tr_backlight patch, but
I made no attempt at merging the two since the tr_backlight patch is not
applied yet and is probably 3.5 material anyway. I'm more than happy to
work with Akio to fix up the conflicts.
drivers/platform/x86/toshiba_acpi.c | 77 ++++++++++++++++++++++++-----------
1 file changed, 54 insertions(+), 23 deletions(-)
diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index ee79ce6..33ee2e8 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -480,9 +480,8 @@ static const struct rfkill_ops toshiba_rfk_ops = {
static struct proc_dir_entry *toshiba_proc_dir /*= 0*/ ;
-static int get_lcd(struct backlight_device *bd)
+static int __get_lcd_brightness(struct toshiba_acpi_dev *dev)
{
- struct toshiba_acpi_dev *dev = bl_get_data(bd);
u32 hci_result;
u32 value;
@@ -493,6 +492,12 @@ static int get_lcd(struct backlight_device *bd)
return -EIO;
}
+static int get_lcd_brightness(struct backlight_device *bd)
+{
+ struct toshiba_acpi_dev *dev = bl_get_data(bd);
+ return __get_lcd_brightness(dev);
+}
+
static int lcd_proc_show(struct seq_file *m, void *v)
{
struct toshiba_acpi_dev *dev = m->private;
@@ -501,7 +506,7 @@ static int lcd_proc_show(struct seq_file *m, void *v)
if (!dev->backlight_dev)
return -ENODEV;
- value = get_lcd(dev->backlight_dev);
+ value = get_lcd_brightness(dev->backlight_dev);
if (value >= 0) {
seq_printf(m, "brightness: %d\n", value);
seq_printf(m, "brightness_levels: %d\n",
@@ -518,7 +523,7 @@ static int lcd_proc_open(struct inode *inode, struct file *file)
return single_open(file, lcd_proc_show, PDE(inode)->data);
}
-static int set_lcd(struct toshiba_acpi_dev *dev, int value)
+static int set_lcd_brightness(struct toshiba_acpi_dev *dev, int value)
{
u32 hci_result;
@@ -530,7 +535,7 @@ static int set_lcd(struct toshiba_acpi_dev *dev, int value)
static int set_lcd_status(struct backlight_device *bd)
{
struct toshiba_acpi_dev *dev = bl_get_data(bd);
- return set_lcd(dev, bd->props.brightness);
+ return set_lcd_brightness(dev, bd->props.brightness);
}
static ssize_t lcd_proc_write(struct file *file, const char __user *buf,
@@ -549,7 +554,7 @@ static ssize_t lcd_proc_write(struct file *file, const char __user *buf,
if (sscanf(cmd, " brightness : %i", &value) == 1 &&
value >= 0 && value < HCI_LCD_BRIGHTNESS_LEVELS) {
- ret = set_lcd(dev, value);
+ ret = set_lcd_brightness(dev, value);
if (ret == 0)
ret = count;
} else {
@@ -860,8 +865,8 @@ static void remove_toshiba_proc_entries(struct toshiba_acpi_dev *dev)
}
static const struct backlight_ops toshiba_backlight_data = {
- .get_brightness = get_lcd,
- .update_status = set_lcd_status,
+ .get_brightness = get_lcd_brightness,
+ .update_status = set_lcd_status,
};
static bool toshiba_acpi_i8042_filter(unsigned char data, unsigned char str,
@@ -1020,6 +1025,45 @@ static int __devinit toshiba_acpi_setup_keyboard(struct toshiba_acpi_dev *dev)
return error;
}
+static int __devinit toshiba_acpi_setup_backlight(struct toshiba_acpi_dev *dev)
+{
+ struct backlight_properties props;
+ int brightness;
+ int ret;
+
+ /*
+ * Some machines don't support the backlight methods at all, and
+ * others support it read-only. Either of these is pretty useless,
+ * so only register the backlight device if the backlight method
+ * supports both reads and writes.
+ */
+ brightness = __get_lcd_brightness(dev);
+ if (brightness < 0)
+ return 0;
+ ret = set_lcd_brightness(dev, brightness);
+ if (ret) {
+ pr_debug("Backlight method is read-only, disabling backlight support\n");
+ return 0;
+ }
+
+ props.type = BACKLIGHT_PLATFORM;
+ props.max_brightness = HCI_LCD_BRIGHTNESS_LEVELS - 1;
+ dev->backlight_dev = backlight_device_register("toshiba",
+ &dev->acpi_dev->dev,
+ dev,
+ &toshiba_backlight_data,
+ &props);
+ if (IS_ERR(dev->backlight_dev)) {
+ ret = PTR_ERR(dev->backlight_dev);
+ pr_err("Could not register toshiba backlight device\n");
+ dev->backlight_dev = NULL;
+ return ret;
+ }
+
+ dev->backlight_dev->props.brightness = brightness;
+ return 0;
+}
+
static int toshiba_acpi_remove(struct acpi_device *acpi_dev, int type)
{
struct toshiba_acpi_dev *dev = acpi_driver_data(acpi_dev);
@@ -1078,7 +1122,6 @@ static int __devinit toshiba_acpi_add(struct acpi_device *acpi_dev)
u32 dummy;
bool bt_present;
int ret = 0;
- struct backlight_properties props;
if (toshiba_acpi)
return -EBUSY;
@@ -1104,21 +1147,9 @@ static int __devinit toshiba_acpi_add(struct acpi_device *acpi_dev)
mutex_init(&dev->mutex);
- props.type = BACKLIGHT_PLATFORM;
- props.max_brightness = HCI_LCD_BRIGHTNESS_LEVELS - 1;
- dev->backlight_dev = backlight_device_register("toshiba",
- &acpi_dev->dev,
- dev,
- &toshiba_backlight_data,
- &props);
- if (IS_ERR(dev->backlight_dev)) {
- ret = PTR_ERR(dev->backlight_dev);
-
- pr_err("Could not register toshiba backlight device\n");
- dev->backlight_dev = NULL;
+ ret = toshiba_acpi_setup_backlight(dev);
+ if (ret)
goto error;
- }
- dev->backlight_dev->props.brightness = get_lcd(dev->backlight_dev);
/* Register rfkill switch for Bluetooth */
if (hci_get_bt_present(dev, &bt_present) == HCI_SUCCESS && bt_present) {
--
1.7.9.5
--
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