Re: [PATCH 1/3] OMAP: DSS2: Functions to request/release DSI VCs

[Tomi Valkeinen <tomi.valkeinen@ti.com>]

On Mon, 2011-02-28 at 02:47 -0600, Taneja, Archit wrote:
> Introduce functions which request and release VC's. This will be used in panel
> drivers in their probes.
> 
> omap_dsi_request_vc() takes in the pointer to the omap_dss_device, the VC_ID
> parameter which goes into the header of the DSI packets, and returns a Virtual
> channel number (or virtual channel register set) which it can use.
> 
> omap_dsi_releae_vc() takes the omap_dss_device pointer and frees all VCs which
> were used by that device.
> 
> Initialisation of VC parameters is done in dsi_init().
> 
> Signed-off-by: Archit Taneja <archit@ti.com>
> ---
>  arch/arm/plat-omap/include/plat/display.h |    3 ++
>  drivers/video/omap2/dss/dsi.c             |   55 ++++++++++++++++++++++++++---
>  2 files changed, 53 insertions(+), 5 deletions(-)
> 
> diff --git a/arch/arm/plat-omap/include/plat/display.h b/arch/arm/plat-omap/include/plat/display.h
> index d45f107..0057259 100644
> --- a/arch/arm/plat-omap/include/plat/display.h
> +++ b/arch/arm/plat-omap/include/plat/display.h
> @@ -560,6 +560,9 @@ int omap_dsi_update(struct omap_dss_device *dssdev,
>  		int channel,
>  		u16 x, u16 y, u16 w, u16 h,
>  		void (*callback)(int, void *), void *data);
> +int omap_dsi_request_vc(struct omap_dss_device *dssdev, int vc_id,
> +		int *channel);

One more thing: 

In theory the vc_id could be given per transmission, when calling
dsi_vc_send_xxx() functions, like it is currently.

But as the vc_id changes (probably) very rarely, it could be stored like
you do. But we should still have a separate function to set the vc_id,
without having to release and request the vc.

 Tomi