[PATCH] drm/pl111: Fix regression from fbdev CMA helper

[Noralf Trønnes]

Den 12.02.2018 14.42, skrev Noralf Trønnes:
>
> Den 12.02.2018 13.40, skrev Linus Walleij:
>> Commit d18df744de1a ("drm/pl111: Use drm_fb_cma_fbdev_init/fini()")
>> refactored the driver to use fbdev handling in the core, but
>> mistakedly limited the number of maximum connections to 0.
>>
>> Predictably, zero possible connections also gives zero
>> framebuffers when using the system. So let's bump it to 1 so
>> we get our framebuffer back.
>>
>> Cc: Noralf Trønnes <noralf at tronnes.org>
>> Cc: Eric Anholt <eric at anholt.net>
>> Fixes: d18df744de1a ("drm/pl111: Use drm_fb_cma_fbdev_init/fini()")
>> Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
>> ---
>>   drivers/gpu/drm/pl111/pl111_drv.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/pl111/pl111_drv.c 
>> b/drivers/gpu/drm/pl111/pl111_drv.c
>> index acb738c69873..306ac7cabd90 100644
>> --- a/drivers/gpu/drm/pl111/pl111_drv.c
>> +++ b/drivers/gpu/drm/pl111/pl111_drv.c
>> @@ -138,7 +138,7 @@ static int pl111_modeset_init(struct drm_device 
>> *dev)
>>         drm_mode_config_reset(dev);
>>   -    drm_fb_cma_fbdev_init(dev, 32, 0);
>> +    drm_fb_cma_fbdev_init(dev, 32, 1);
>>         drm_kms_helper_poll_init(dev);
>
> Sorry about that.
>
> I don't know how bridges work, but since it doesn't work this means that
> there's no connector available at this point?
>
> This is the arg docs:
>
>  * @max_conn_count: Maximum number of connectors.
>  *                  @dev->mode_config.num_connector is used if this is 
> zero.
>
> Anyways:
> Acked-by: Noralf Trønnes <noralf at tronnes.org>
>

I forgot to look at the change, and I don't understand how this broke 
anything,

drm/pl111: Use drm_fb_cma_fbdev_init/fini():

@@ -137,8 +138,7 @@ static int pl111_modeset_init(struct drm_device *dev)

      drm_mode_config_reset(dev);

-    priv->fbdev = drm_fbdev_cma_init(dev, 32,
-                     dev->mode_config.num_connector);
+    drm_fb_cma_fbdev_init(dev, 32, 0);

      drm_kms_helper_poll_init(dev);

New max_conn_count setting:

int drm_fb_cma_fbdev_init(struct drm_device *dev, unsigned int 
preferred_bpp,
               unsigned int max_conn_count)
{
     return drm_fb_cma_fbdev_init_with_funcs(dev, preferred_bpp,
                         max_conn_count, NULL);
}

int drm_fb_cma_fbdev_init_with_funcs(struct drm_device *dev,
     unsigned int preferred_bpp, unsigned int max_conn_count,
     const struct drm_framebuffer_funcs *funcs)
{
...
     if (!max_conn_count)
         max_conn_count = dev->mode_config.num_connector;

Noralf.