Re: [PATCH] drm/i915/display: Add default case to mipi_exec_send_packet

[Jani Nikula <jani.nikula@linux.intel.com>]

On Tue, 04 Nov 2025, Jani Nikula <jani.nikula@linux.intel.com> wrote:
> On Tue, 04 Nov 2025, Jonathan Cavitt <jonathan.cavitt@intel.com> wrote:
>> Add a default case to the switch case statement in mipi_exec_send_packet
>> to prevent attempts to read an uninitialized ret value.  It's unlikely
>> the default case will ever occur during regular exeuction, but if more
>> MIPI DSI Processor-to-Peripheral transaction types are ever added, then
>> having this in place will be a useful safety guard.
>>
>> Signed-off-by: Jonathan Cavitt <jonathan.cavitt@intel.com>
>
> Fixes: 23db1577ce2d ("drm/i915/dsi: log send packet sequence errors")
> Reviewed-by: Jani Nikula <jani.nikula@intel.com>

Fell between the cracks a bit, but pushed now.

Thanks for the patch.

>
>> ---
>>  drivers/gpu/drm/i915/display/intel_dsi_vbt.c | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
>> index 31edf57a296f..4b815ce6b1fe 100644
>> --- a/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
>> +++ b/drivers/gpu/drm/i915/display/intel_dsi_vbt.c
>> @@ -171,6 +171,9 @@ static const u8 *mipi_exec_send_packet(struct intel_dsi *intel_dsi,
>>  	case MIPI_DSI_DCS_LONG_WRITE:
>>  		ret = mipi_dsi_dcs_write_buffer(dsi_device, data, len);
>>  		break;
>> +	default:
>> +		ret = -EINVAL;
>> +		break;
>>  	}
>>  
>>  	if (ret < 0)

-- 
Jani Nikula, Intel