Re: [PATCH v3 22/24] drm/rockchip: dw-mipi-dsi: support non-burst modes

From: John Keeping
Date: Thu Feb 16 2017 - 09:22:52 EST


On Thu, 16 Feb 2017 11:01:46 +0800, Chris Zhong wrote:

> On 02/01/2017 03:22 AM, Sean Paul wrote:
> > On Sun, Jan 29, 2017 at 01:24:42PM +0000, John Keeping wrote:
> >
> > Reviewed-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
> >
> >> Signed-off-by: John Keeping <john@xxxxxxxxxxxx>
> >> Reviewed-by: Chris Zhong <zyw@xxxxxxxxxxxxxx>
> >> ---
> >> v3:
> >> - Add Chris' Reviewed-by
> >> Unchanged in v2
> >>
> >> drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 16 +++++++++-------
> >> 1 file changed, 9 insertions(+), 7 deletions(-)
> >>
> >> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> >> index 5bad92e2370e..58cb8ace2fe8 100644
> >> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> >> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> >> @@ -82,6 +82,7 @@
> >> #define FRAME_BTA_ACK BIT(14)
> >> #define ENABLE_LOW_POWER (0x3f << 8)
> >> #define ENABLE_LOW_POWER_MASK (0x3f << 8)
> >> +#define VID_MODE_TYPE_NON_BURST_SYNC_EVENTS 0x1
> >> #define VID_MODE_TYPE_BURST_SYNC_PULSES 0x2
> This field indicates the video mode transmission type as follows:
> 00: Non-burst with sync pulses
> 01: Non-burst with sync events
> 10 and 11: Burst mode
>
> So, I think define the macro like this is better:
>
> #define VID_MODE_TYPE_NON_BURST_SYNC_PULSES 0x0
> #define VID_MODE_TYPE_NON_BURST_SYNC_EVENTS 0x1
> #define VID_MODE_TYPE_BURST 0x2
>
>
> >> #define VID_MODE_TYPE_MASK 0x3
> >>
> >> @@ -286,6 +287,7 @@ struct dw_mipi_dsi {
> >> u32 format;
> >> u16 input_div;
> >> u16 feedback_div;
> >> + unsigned long mode_flags;
> >>
> >> const struct dw_mipi_dsi_plat_data *pdata;
> >> };
> >> @@ -551,15 +553,10 @@ static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host,
> >> return -EINVAL;
> >> }
> >>
> >> - if (!(device->mode_flags & MIPI_DSI_MODE_VIDEO_BURST) ||
> >> - !(device->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)) {
> >> - dev_err(dsi->dev, "device mode is unsupported\n");
> >> - return -EINVAL;
> >> - }
> >> -
> >> dsi->lanes = device->lanes;
> >> dsi->channel = device->channel;
> >> dsi->format = device->format;
> >> + dsi->mode_flags = device->mode_flags;
> >> dsi->panel = of_drm_find_panel(device->dev.of_node);
> >> if (dsi->panel)
> >> return drm_panel_attach(dsi->panel, &dsi->connector);
> >> @@ -716,7 +713,12 @@ static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
> >> {
> >> u32 val;
> >>
> >> - val = VID_MODE_TYPE_BURST_SYNC_PULSES | ENABLE_LOW_POWER;
> >> + val = ENABLE_LOW_POWER;
> >> +
> >> + if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
> >> + val |= VID_MODE_TYPE_BURST_SYNC_PULSES;
> >> + else if (!(dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE))
> >> + val |= VID_MODE_TYPE_NON_BURST_SYNC_EVENTS;
>
> if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
> val |= VID_MODE_TYPE_BURST;
> else if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
> val |= VID_MODE_TYPE_NON_BURST_SYNC_PULSES;
> else
> val |= VID_MODE_TYPE_NON_BURST_SYNC_EVENTS;

OK, this is definitely clearer now that I've forgotten most of the
datasheet; without your definitions at the top it's not clear that
VID_MODE_TYPE_BURST_SYNC_PULSES is zero.