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:

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@linux.intel.com --- sound/pci/hda/hda_proc.c | 38 +++++++++++++++++++++++++++++++++++++- 1 file changed, 37 insertions(+), 1 deletion(-)

v2 changes: - add NULL check to conn array allocation - put a few functions to a single line as they fit within 100 columns - reformat the first paragraph of commit message

diff --git a/sound/pci/hda/hda_proc.c b/sound/pci/hda/hda_proc.c index 0631f31ef87f..00c2eeb2c472 100644 --- a/sound/pci/hda/hda_proc.c +++ b/sound/pci/hda/hda_proc.c @@ -679,6 +679,38 @@ 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); + if (!conn) + return; + + dev_id_saved = snd_hda_get_dev_select(codec, nid); + + snd_hda_set_dev_select(codec, nid, dev_num); + curr = snd_hda_codec_read(codec, nid, 0, AC_VERB_GET_CONNECT_SEL, 0); + if (snd_hda_get_raw_connections(codec, nid, conn, conn_len) < 0) + goto out; + + for (c = 0; c < conn_len; c++) { + snd_iprintf(buffer, " 0x%02x", conn[c]); + if (c == curr) + snd_iprintf(buffer, "*"); + } + +out: + kfree(conn); + snd_hda_set_dev_select(codec, nid, dev_id_saved); +} + static void print_device_list(struct snd_info_buffer *buffer, struct hda_codec *codec, hda_nid_t nid) { @@ -702,10 +734,14 @@ static void print_device_list(struct snd_info_buffer *buffer, snd_iprintf(buffer, " ");

snd_iprintf(buffer, - "Dev %02d: PD = %d, ELDV = %d, IA = %d\n", i, + "Dev %02d: PD = %d, ELDV = %d, IA = %d, Connections [", i, !!(dev_list[i] & AC_DE_PD), !!(dev_list[i] & AC_DE_ELDV), !!(dev_list[i] & AC_DE_IA)); + + print_dpmst_connections(buffer, codec, nid, i); + + snd_iprintf(buffer, " ]\n"); } }