Re: [PATCH v7 6/8] Loongson: YeeLoong: add video output driver

[Wu Zhangjin <wuzhangjin@gmail.com>]

On Fri, 2009-12-04 at 09:11 +0100, Pavel Machek wrote:
> On Fri 2009-12-04 21:36:43, Wu Zhangjin wrote:
> > From: Wu Zhangjin <wuzhangjin@gmail.com>
> > 
> > This patch adds Video Output Driver, it provides standard
> > interface(/sys/class/video_output) to turn on/off the video output of
> > LCD, CRT.
> > 
> 
> > diff --git a/drivers/platform/mips/Kconfig b/drivers/platform/mips/Kconfig
> > index 9c8385c..4a89c01 100644
> > --- a/drivers/platform/mips/Kconfig
> > +++ b/drivers/platform/mips/Kconfig
> > @@ -21,6 +21,7 @@ config LEMOTE_YEELOONG2F
> >     select SYS_SUPPORTS_APM_EMULATION
> >     select APM_EMULATION
> >     select HWMON
> > +   select VIDEO_OUTPUT_CONTROL
> >     default m
> >     help
> >       YeeLoong netbook is a mini laptop made by Lemote, which is basically
> 
> default m is evil.
> 

why? this module can be loaded automatically, so, I let it be a module
by default.

> > +   if (status == BIT_DISPLAY_LCD_ON) {
> > +           /* Turn on LCD */
> > +           outb(0x31, 0x3c4);
> > +           value = inb(0x3c5);
> > +           value = (value & 0xf8) | 0x03;
> > +           outb(0x31, 0x3c4);
> > +           outb(value, 0x3c5);
> > +           /* Turn on backlight */
> > +           ec_write(REG_BACKLIGHT_CTRL, BIT_BACKLIGHT_ON);
> > +   } else {
> > +           /* Turn off backlight */
> > +           ec_write(REG_BACKLIGHT_CTRL, BIT_BACKLIGHT_OFF);
> > +           /* Turn off LCD */
> > +           outb(0x31, 0x3c4);
> > +           value = inb(0x3c5);
> > +           value = (value & 0xf8) | 0x02;
> > +           outb(0x31, 0x3c4);
> > +           outb(value, 0x3c5);
> > +   }
> 
> IIRC this is opencoded in suspend support; should that get common
> helpers?
> 
> > +   if (status == BIT_CRT_DETECT_PLUG) {
> > +           if (ec_read(REG_CRT_DETECT) == BIT_CRT_DETECT_PLUG) {
> > +                   /* Turn on CRT */
> > +                   outb(0x21, 0x3c4);
> > +                   value = inb(0x3c5);
> > +                   value &= ~(1 << 7);
> > +                   outb(0x21, 0x3c4);
> > +                   outb(value, 0x3c5);
> > +           }
> > +   } else {
> > +           /* Turn off CRT */
> > +           outb(0x21, 0x3c4);
> > +           value = inb(0x3c5);
> > +           value |= (1 << 7);
> > +           outb(0x21, 0x3c4);
> > +           outb(value, 0x3c5);
> > +   }
> 
> This looks suspiciously similar to one another and to code
> above. Perhaps some more helpers?
> 

Yes, lots of duplicated source code above, thanks!

Regards,
        Wu Zhangjin