[PATCH v2] drm/arcpgu: Accommodate adv7511 switch to DRM bridge

[Ramiro Oliveira]

On 10/19/2016 01:16 PM, Eugeniy Paltsev wrote:
> ARC PGU driver starts crashing on initialization after
> 'commit e12c2f645557 ("drm/i2c: adv7511: Convert to drm_bridge")'
> This happenes because in "arcpgu_drm_hdmi_init" function we get pointer
> of "drm_i2c_encoder_driver" structure, which doesn't exist after
> adv7511 hdmi encoder interface changed from slave encoder to drm bridge.
> So, when we call "encoder_init" function from this structure driver
> crashes.
> 
> Bootlog:
> ------------------------------------->8--------------------------------
> [drm] Initialized drm 1.1.0 20060810
> arcpgu e0017000.pgu: arc_pgu ID: 0xabbabaab
> arcpgu e0017000.pgu: assigned reserved memory node frame_buffer at 9e000000
> Path: (null)
> CPU: 0 PID: 1 Comm: swapper Not tainted 4.8.0-00001-gb5642252fa01-dirty #8
> task: 9a058000 task.stack: 9a032000
> 
> [ECR   ]: 0x00220100 => Invalid Read @ 0x00000004 by insn @ 0x803934e8
> [EFA   ]: 0x00000004
> [BLINK ]: drm_atomic_helper_connector_dpms+0xa6/0x230
> [ERET  ]: drm_atomic_helper_connector_dpms+0xa4/0x230
> [STAT32]: 0x00000846 : K DE       E2 E1
> BTA: 0x8016d949  SP: 0x9a033e34  FP: 0x00000000
> LPS: 0x8036f6fc LPE: 0x8036f700 LPC: 0x00000000
> r00: 0x8063c118 r01: 0x805b98ac r02: 0x00000b11
> r03: 0x00000000 r04: 0x9a010f54 r05: 0x00000000
> r06: 0x00000001 r07: 0x00000000 r08: 0x00000028
> r09: 0x00000001 r10: 0x00000007 r11: 0x00000054
> r12: 0x720a3033
> 
> Stack Trace:
>   drm_atomic_helper_connector_dpms+0xa4/0x230
>   arcpgu_drm_hdmi_init+0xbc/0x228
>   arcpgu_probe+0x168/0x244
>   platform_drv_probe+0x26/0x64
>   really_probe+0x1f0/0x32c
>   __driver_attach+0xa8/0xd0
>   bus_for_each_dev+0x3c/0x74
>   bus_add_driver+0xc2/0x184
>   driver_register+0x50/0xec
>   do_one_initcall+0x3a/0x120
>   kernel_init_freeable+0x108/0x1a0
> ------------------------------------->8--------------------------------
> 
> Fix ARC PGU driver to be able work with drm bridge hdmi encoder
> interface. The hdmi connector code isn't needed anymore as we expect
> the adv7511 bridge driver to create/manage the connector.

Tested-by: Ramiro Oliveira <Ramiro.Oliveira at synopsys.com>