Re: [PATCH v4] toshiba_acpi: Add support for transflective LCD

[Seth Forshee <seth.forshee@canonical.com>]

On Fri, Apr 06, 2012 at 01:46:43AM +0900, Akio Idehara wrote:
> 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>

Looks good.

Acked-by: Seth Forshee <seth.forshee@canonical.com>

> ---
>  drivers/platform/x86/toshiba_acpi.c |   63 +++++++++++++++++++++++++++++++---
>  1 files changed, 57 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
> index ee79ce6..cc0641b 100644
> --- a/drivers/platform/x86/toshiba_acpi.c
> +++ b/drivers/platform/x86/toshiba_acpi.c
> @@ -95,6 +95,7 @@ MODULE_LICENSE("GPL");
>  
>  /* 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 @@ struct toshiba_acpi_dev {
>  	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;
>  };
> @@ -478,6 +480,25 @@ static const struct rfkill_ops toshiba_rfk_ops = {
>  	.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(struct backlight_device *bd)
> @@ -485,10 +506,21 @@ static int get_lcd(struct backlight_device *bd)
>  	struct toshiba_acpi_dev *dev = bl_get_data(bd);
>  	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;
>  }
> @@ -497,15 +529,16 @@ static int lcd_proc_show(struct seq_file *m, void *v)
>  {
>  	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(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;
>  	}
>  
> @@ -521,6 +554,14 @@ static int lcd_proc_open(struct inode *inode, struct file *file)
>  static int set_lcd(struct toshiba_acpi_dev *dev, int value)
>  {
>  	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);
> @@ -541,6 +582,7 @@ static ssize_t lcd_proc_write(struct file *file, const char __user *buf,
>  	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))
> @@ -548,7 +590,7 @@ static ssize_t lcd_proc_write(struct file *file, const char __user *buf,
>  	cmd[len] = '\0';
>  
>  	if (sscanf(cmd, " brightness : %i", &value) == 1 &&
> -	    value >= 0 && value < HCI_LCD_BRIGHTNESS_LEVELS) {
> +	    value >= 0 && value < levels) {
>  		ret = set_lcd(dev, value);
>  		if (ret == 0)
>  			ret = count;
> @@ -860,8 +902,9 @@ 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,
> +	.options	= BL_CORE_SUSPENDRESUME,
> +	.get_brightness	= get_lcd,
> +	.update_status	= set_lcd_status,
>  };
>  
>  static bool toshiba_acpi_i8042_filter(unsigned char data, unsigned char str,
> @@ -1079,6 +1122,7 @@ static int __devinit toshiba_acpi_add(struct acpi_device *acpi_dev)
>  	bool bt_present;
>  	int ret = 0;
>  	struct backlight_properties props;
> +	bool enabled;
>  
>  	if (toshiba_acpi)
>  		return -EBUSY;
> @@ -1104,8 +1148,15 @@ static int __devinit toshiba_acpi_add(struct acpi_device *acpi_dev)
>  
>  	mutex_init(&dev->mutex);
>  
> +	/* 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;
> +	/* 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",
>  						       &acpi_dev->dev,
>  						       dev,
> -- 
> 1.7.7.6
>