Because the eld buffer can be simultaneously accessed from both workqueue context (updating) and process context (kcontrol read), we need to protect it with a mutex to guarantee consistency.
To avoid holding the mutex while reading the ELD info from the codec, we introduce a temporary eld buffer.
Signed-off-by: David Henningsson david.henningsson@canonical.com --- sound/pci/hda/hda_eld.c | 8 ++++++- sound/pci/hda/hda_local.h | 1 + sound/pci/hda/patch_hdmi.c | 51 +++++++++++++++++++++++++++++++++----------- 3 files changed, 47 insertions(+), 13 deletions(-)
diff --git a/sound/pci/hda/hda_eld.c b/sound/pci/hda/hda_eld.c index 16066d7..7dd8463 100644 --- a/sound/pci/hda/hda_eld.c +++ b/sound/pci/hda/hda_eld.c @@ -500,10 +500,13 @@ static void hdmi_print_eld_info(struct snd_info_entry *entry, [4 ... 7] = "reserved" };
+ mutex_lock(&eld->lock); snd_iprintf(buffer, "monitor_present\t\t%d\n", eld->monitor_present); snd_iprintf(buffer, "eld_valid\t\t%d\n", eld->eld_valid); - if (!eld->eld_valid) + if (!eld->eld_valid) { + mutex_unlock(&eld->lock); return; + } snd_iprintf(buffer, "monitor_name\t\t%s\n", e->monitor_name); snd_iprintf(buffer, "connection_type\t\t%s\n", eld_connection_type_names[e->conn_type]); @@ -525,6 +528,7 @@ static void hdmi_print_eld_info(struct snd_info_entry *entry,
for (i = 0; i < e->sad_count; i++) hdmi_print_sad_info(i, e->sad + i, buffer); + mutex_unlock(&eld->lock); }
static void hdmi_write_eld_info(struct snd_info_entry *entry, @@ -538,6 +542,7 @@ static void hdmi_write_eld_info(struct snd_info_entry *entry, long long val; unsigned int n;
+ mutex_lock(&eld->lock); while (!snd_info_get_line(buffer, line, sizeof(line))) { if (sscanf(line, "%s %llx", name, &val) != 2) continue; @@ -589,6 +594,7 @@ static void hdmi_write_eld_info(struct snd_info_entry *entry, e->sad_count = n + 1; } } + mutex_unlock(&eld->lock); }
diff --git a/sound/pci/hda/hda_local.h b/sound/pci/hda/hda_local.h index 363cd48..83b7486 100644 --- a/sound/pci/hda/hda_local.h +++ b/sound/pci/hda/hda_local.h @@ -739,6 +739,7 @@ struct hdmi_eld { int eld_size; char eld_buffer[ELD_MAX_SIZE]; struct parsed_hdmi_eld info; + struct mutex lock; #ifdef CONFIG_PROC_FS struct snd_info_entry *proc_entry; #endif diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c index 1e38191..e77735d 100644 --- a/sound/pci/hda/patch_hdmi.c +++ b/sound/pci/hda/patch_hdmi.c @@ -91,6 +91,7 @@ struct hdmi_spec { struct hda_pcm pcm_rec[MAX_HDMI_PINS]; unsigned int channels_max; /* max over all cvts */
+ struct hdmi_eld temp_eld; /* * Non-generic ATI/NVIDIA specific */ @@ -352,7 +353,9 @@ static int hdmi_eld_ctl_info(struct snd_kcontrol *kcontrol, pin_idx = kcontrol->private_value; eld = &spec->pins[pin_idx].sink_eld;
+ mutex_lock(&eld->lock); uinfo->count = eld->eld_valid ? eld->eld_size : 0; + mutex_unlock(&eld->lock);
return 0; } @@ -368,7 +371,9 @@ static int hdmi_eld_ctl_get(struct snd_kcontrol *kcontrol, pin_idx = kcontrol->private_value; eld = &spec->pins[pin_idx].sink_eld;
+ mutex_lock(&eld->lock); if (eld->eld_size > ARRAY_SIZE(ucontrol->value.bytes.data)) { + mutex_unlock(&eld->lock); snd_BUG(); return -EINVAL; } @@ -378,6 +383,7 @@ static int hdmi_eld_ctl_get(struct snd_kcontrol *kcontrol, if (eld->eld_valid) memcpy(ucontrol->value.bytes.data, eld->eld_buffer, eld->eld_size); + mutex_unlock(&eld->lock);
return 0; } @@ -1164,7 +1170,9 @@ static int hdmi_read_pin_conn(struct hda_codec *codec, int pin_idx) static void hdmi_present_sense(struct hdmi_spec_per_pin *per_pin, int repoll) { struct hda_codec *codec = per_pin->codec; - struct hdmi_eld *eld = &per_pin->sink_eld; + struct hdmi_spec *spec = codec->spec; + struct hdmi_eld *eld = &spec->temp_eld; + struct hdmi_eld *pin_eld = &per_pin->sink_eld; hda_nid_t pin_nid = per_pin->pin_nid; /* * Always execute a GetPinSense verb here, even when called from @@ -1175,38 +1183,56 @@ static void hdmi_present_sense(struct hdmi_spec_per_pin *per_pin, int repoll) * the unsolicited response to avoid custom WARs. */ int present = snd_hda_pin_sense(codec, pin_nid); - bool eld_valid = false; + bool update_eld = false; + bool eld_changed = false;
- eld->monitor_present = !!(present & AC_PINSENSE_PRESENCE); - if (eld->monitor_present) - eld_valid = !!(present & AC_PINSENSE_ELDV); + pin_eld->monitor_present = !!(present & AC_PINSENSE_PRESENCE); + if (pin_eld->monitor_present) + eld->eld_valid = !!(present & AC_PINSENSE_ELDV); + else + eld->eld_valid = false;
_snd_printd(SND_PR_VERBOSE, "HDMI status: Codec=%d Pin=%d Presence_Detect=%d ELD_Valid=%d\n", - codec->addr, pin_nid, eld->monitor_present, eld_valid); + codec->addr, pin_nid, eld->monitor_present, eld->eld_valid);
- eld->eld_valid = false; - if (eld_valid) { + if (eld->eld_valid) { if (snd_hdmi_get_eld(codec, pin_nid, eld->eld_buffer, &eld->eld_size) < 0) - eld_valid = false; + eld->eld_valid = false; else { memset(&eld->info, 0, sizeof(struct parsed_hdmi_eld)); if (snd_hdmi_parse_eld(&eld->info, eld->eld_buffer, eld->eld_size) < 0) - eld_valid = false; + eld->eld_valid = false; }
- if (eld_valid) { + if (eld->eld_valid) { snd_hdmi_show_eld(&eld->info); - eld->eld_valid = true; + update_eld = true; } else if (repoll) { queue_delayed_work(codec->bus->workq, &per_pin->work, msecs_to_jiffies(300)); + return; } } + + mutex_lock(&pin_eld->lock); + if (pin_eld->eld_valid && !eld->eld_valid) + update_eld = true; + if (update_eld) { + pin_eld->eld_valid = eld->eld_valid; + eld_changed = memcmp(pin_eld->eld_buffer, eld->eld_buffer, + eld->eld_size) != 0; + if (eld_changed) + memcpy(pin_eld->eld_buffer, eld->eld_buffer, + eld->eld_size); + pin_eld->eld_size = eld->eld_size; + pin_eld->info = eld->info; + } + mutex_unlock(&pin_eld->lock); }
static void hdmi_repoll_eld(struct work_struct *work) @@ -1674,6 +1700,7 @@ static int generic_hdmi_init_per_pins(struct hda_codec *codec) struct hdmi_eld *eld = &per_pin->sink_eld;
per_pin->codec = codec; + mutex_init(&eld->lock); INIT_DELAYED_WORK(&per_pin->work, hdmi_repoll_eld); snd_hda_eld_proc_new(codec, eld, pin_idx); }