Re: [PATCH AUTOSEL 6.14 483/642] drm/amd/display/dc: enable oem i2c support for DCE 12.x

[Alex Deucher <alexdeucher@gmail.com>]

On Mon, May 5, 2025 at 6:34 PM Sasha Levin <sashal@kernel.org> wrote:
>
> From: Alex Deucher <alexander.deucher@amd.com>
>
> [ Upstream commit 2ed83f2cc41e8f7ced1c0610ec2b0821c5522ed5 ]
>
> Use the value pulled from the vbios just like newer chips.
>
> Reviewed-by: Harry Wentland <harry.wentland@amd.com>
> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
> Signed-off-by: Sasha Levin <sashal@kernel.org>

This isn't a bug fix.  This is a new feature and depends on other
changes to actually utilize.

Alex

> ---
>  .../dc/resource/dce120/dce120_resource.c        | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c
> index c63c596234333..eb1e158d34361 100644
> --- a/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c
> +++ b/drivers/gpu/drm/amd/display/dc/resource/dce120/dce120_resource.c
> @@ -67,6 +67,7 @@
>  #include "reg_helper.h"
>
>  #include "dce100/dce100_resource.h"
> +#include "link.h"
>
>  #ifndef mmDP0_DP_DPHY_INTERNAL_CTRL
>         #define mmDP0_DP_DPHY_INTERNAL_CTRL             0x210f
> @@ -659,6 +660,12 @@ static void dce120_resource_destruct(struct dce110_resource_pool *pool)
>
>         if (pool->base.dmcu != NULL)
>                 dce_dmcu_destroy(&pool->base.dmcu);
> +
> +       if (pool->base.oem_device != NULL) {
> +               struct dc *dc = pool->base.oem_device->ctx->dc;
> +
> +               dc->link_srv->destroy_ddc_service(&pool->base.oem_device);
> +       }
>  }
>
>  static void read_dce_straps(
> @@ -1054,6 +1061,7 @@ static bool dce120_resource_construct(
>         struct dc *dc,
>         struct dce110_resource_pool *pool)
>  {
> +       struct ddc_service_init_data ddc_init_data = {0};
>         unsigned int i;
>         int j;
>         struct dc_context *ctx = dc->ctx;
> @@ -1257,6 +1265,15 @@ static bool dce120_resource_construct(
>
>         bw_calcs_data_update_from_pplib(dc);
>
> +       if (dc->ctx->dc_bios->fw_info.oem_i2c_present) {
> +               ddc_init_data.ctx = dc->ctx;
> +               ddc_init_data.link = NULL;
> +               ddc_init_data.id.id = dc->ctx->dc_bios->fw_info.oem_i2c_obj_id;
> +               ddc_init_data.id.enum_id = 0;
> +               ddc_init_data.id.type = OBJECT_TYPE_GENERIC;
> +               pool->base.oem_device = dc->link_srv->create_ddc_service(&ddc_init_data);
> +       }
> +
>         return true;
>
>  irqs_create_fail:
> --
> 2.39.5
>