[PATCH v17 2/7] video: add display_timing and videomode

[Steffen Trumtrar]

Ah, sorry. Forgot to answer this.

On Wed, Feb 27, 2013 at 05:45:31PM +0200, Tomi Valkeinen wrote:
> Ping.
> 
> On 2013-02-18 16:09, Tomi Valkeinen wrote:
> > Hi Steffen,
> > 
> > On 2013-01-25 11:01, Steffen Trumtrar wrote:
> > 
> >> +/* VESA display monitor timing parameters */
> >> +#define VESA_DMT_HSYNC_LOW		BIT(0)
> >> +#define VESA_DMT_HSYNC_HIGH		BIT(1)
> >> +#define VESA_DMT_VSYNC_LOW		BIT(2)
> >> +#define VESA_DMT_VSYNC_HIGH		BIT(3)
> >> +
> >> +/* display specific flags */
> >> +#define DISPLAY_FLAGS_DE_LOW		BIT(0)	/* data enable flag */
> >> +#define DISPLAY_FLAGS_DE_HIGH		BIT(1)
> >> +#define DISPLAY_FLAGS_PIXDATA_POSEDGE	BIT(2)	/* drive data on pos. edge */
> >> +#define DISPLAY_FLAGS_PIXDATA_NEGEDGE	BIT(3)	/* drive data on neg. edge */
> >> +#define DISPLAY_FLAGS_INTERLACED	BIT(4)
> >> +#define DISPLAY_FLAGS_DOUBLESCAN	BIT(5)
> > 
> > <snip>
> > 
> >> +	unsigned int dmt_flags;	/* VESA DMT flags */
> >> +	unsigned int data_flags; /* video data flags */
> > 
> > Why did you go for this approach? To be able to represent
> > true/false/not-specified?
> > 

We decided somewhere between v3 and v8 (I think), that those flags can be
high/low/ignored.

> > Would it be simpler to just have "flags" field? What does it give us to
> > have those two separately?
> > 

I decided to split them, so it is clear that some flags are VESA defined and
the others are "invented" for the display-timings framework and may be
extended.

> > Should the above say raising edge/falling edge instead of positive
> > edge/negative edge?
> > 

Hm, I used posedge/negedge because it is shorter (and because of my Verilog past
pretty natural to me :-) ). I don't know what others are thinking though.

Regards,
Steffen

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