On Tue, 08 Dec 2020 17:09:41 +0100,
Kai Vehmanen wrote:
>
> To help in debugging issues with DisplayPort Multi-Stream Transport (aka
> DP-MST) support, print information of active connections for
> each device of a display audio pin widget.
>
> Example output with the patch with two monitors connected to a DP-MST hub:
Somehow the text is folded irregularly...
> Devices: 4
> Dev 00: PD = 0, ELDV = 0, IA = 0, Connections [ 0x03* 0x05 0x07 0x09 ]
> Dev 01: PD = 1, ELDV = 1, IA = 0, Connections [ 0x03* 0x05 0x07 0x09 ]
> *Dev 02: PD = 1, ELDV = 1, IA = 0, Connections [ 0x03 0x05* 0x07 0x09 ]
> Dev 03: PD = 0, ELDV = 0, IA = 0, Connections [ 0x03* 0x05 0x07 0x09 ]
> Connection: 4
> 0x03 0x05* 0x07 0x09
>
> Format of existing "Connection:" entry is left intact to keep
> compatibility.
>
> Signed-off-by: Kai Vehmanen <kai.vehmanen@xxxxxxxxxxxxxxx>
> ---
> sound/pci/hda/hda_proc.c | 39 ++++++++++++++++++++++++++++++++++++++-
> 1 file changed, 38 insertions(+), 1 deletion(-)
>
> diff --git a/sound/pci/hda/hda_proc.c b/sound/pci/hda/hda_proc.c
> index 0631f31ef87f..e1cba574cadb 100644
> --- a/sound/pci/hda/hda_proc.c
> +++ b/sound/pci/hda/hda_proc.c
> @@ -679,6 +679,39 @@ static void print_gpio(struct snd_info_buffer *buffer,
> print_nid_array(buffer, codec, nid, &codec->nids);
> }
>
> +static void print_dpmst_connections(struct snd_info_buffer *buffer, struct hda_codec *codec,
> + hda_nid_t nid, int dev_num)
> +{
> + int c, conn_len, curr, dev_id_saved;
> + hda_nid_t *conn;
> +
> + conn_len = snd_hda_get_num_raw_conns(codec, nid);
> + if (conn_len <= 0)
> + return;
> +
> + conn = kmalloc_array(conn_len,
> + sizeof(hda_nid_t),
> + GFP_KERNEL);
Missing NULL check? Also you can fold into a single line.
The rest looks good.
thanks,
Takashi
