[PATCH 1/2] panasonic-laptop: add Panasonic Let's Note laptop extras driver v0.94

[Andy Whitcroft]

On Mon, Jan 05, 2009 at 03:31:11PM +0100, Stefan Bader wrote:
> Since it is well isolated to a single driver, ACK. Two small notes, see below)
>
> Andy Whitcroft wrote:
>> Bug: #222324
>> commit 709ee531c153038d81b30649b9eeed3c44a4d5cc
>> This is a driver for ACPI extras such as hotkeys and backlight
>> brightness control on various Panasonic "Let's Note" series laptop
>> computers.
>>
>> It exports the backlight via the backlight class device API,
>> and the hotkeys as input event device.  Some more esoteric
>> items like number of installed batteries are exported via sysfs
>> device attributes.
>>
>> Hotkey events also generate old-style ACPI enents through
>> /proc/acpi/event to interoperate with current versions of acpid.
>>
>
>> --- a/drivers/misc/Kconfig
>> +++ b/drivers/misc/Kconfig
>> @@ -245,6 +245,17 @@ config MSI_LAPTOP
>>   	  If you have an MSI S270 laptop, say Y or M here.
>>  +config PANASONIC_LAPTOP
>> +	tristate "Panasonic Laptop Extras"
>> +	depends on X86 && INPUT
>
> Add ACPI here (see commit 7ba427c2363d91d4221843a9ae601f90f8d928b9)

Added.

> In the driver one minor
>> +
>> +static int bl_set_status(struct backlight_device *bd)
>> +{
>> +	struct pcc_acpi *pcc = bl_get_data(bd);
>> +	int bright = bd->props.brightness;
>> +	int rc;
>> +
>> +	if (!acpi_pcc_retrieve_biosdata(pcc, pcc->sinf))
>> +		return -EIO;
>> +
>> +	if (bright < pcc->sinf[SINF_AC_MIN_BRIGHT])
>> +		bright = pcc->sinf[SINF_AC_MIN_BRIGHT];
>> +
>> +	if (bright < pcc->sinf[SINF_DC_MIN_BRIGHT])
>> +		bright = pcc->sinf[SINF_DC_MIN_BRIGHT];
>> +
>> +	if (bright < pcc->sinf[SINF_AC_MIN_BRIGHT] ||
>> +	    bright > pcc->sinf[SINF_AC_MAX_BRIGHT])
>> +		return -EINVAL;
>> +
>
> Isn't bright always at least pcc->sinf[SINF_AC_MIN_BRIGHT] as it is set 
> above? Might this be meant to check for > SINF_DC_MAX_BRIGHT?

Yeah, it does seems pointless, though it might just represent belt and
braces checks.  I have checked with the upstream version and it has not
changed as yet.  I will report it to the maintainer, but propose to
leave it as it is for the moment.

-apw