ASoC: wm_adsp: Support acknowledged controls

This patch handles publishing acknowledged controls through ALSA.
These controls allow user-side to send events to the firmware and
wait for the firmware to acknowledge it.

Note that although acked controls only operate in the direction
host->firmware, and therefore they are write-only as seen from user-
side code, we have to make them readable to account for all the code
out there that assumes that ALSA controls are always readable (amixer
for example.)

Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c
index d13dd9a9c817fce7eb28e30643eb34b3c2dd6bf3..0f705bfd76b4a3ded42389cf3fe757abe7672578 100644 (file)
--- a/sound/soc/codecs/wm_adsp.c
+++ b/sound/soc/codecs/wm_adsp.c
@@ -164,6 +164,8 @@
 
 #define WM_ADSP_ACKED_CTL_TIMEOUT_MS         100
 #define WM_ADSP_ACKED_CTL_N_QUICKPOLLS       10
+#define WM_ADSP_ACKED_CTL_MIN_VALUE          0
+#define WM_ADSP_ACKED_CTL_MAX_VALUE          0xFFFFFF
 
 /*
  * Event control messages
@@ -761,8 +763,20 @@ static int wm_coeff_info(struct snd_kcontrol *kctl,
                (struct soc_bytes_ext *)kctl->private_value;
        struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
 
-       uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES;
-       uinfo->count = ctl->len;
+       switch (ctl->type) {
+       case WMFW_CTL_TYPE_ACKED:
+               uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
+               uinfo->value.integer.min = WM_ADSP_ACKED_CTL_MIN_VALUE;
+               uinfo->value.integer.max = WM_ADSP_ACKED_CTL_MAX_VALUE;
+               uinfo->value.integer.step = 1;
+               uinfo->count = 1;
+               break;
+       default:
+               uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES;
+               uinfo->count = ctl->len;
+               break;
+       }
+
        return 0;
 }
 
@@ -910,6 +924,30 @@ static int wm_coeff_tlv_put(struct snd_kcontrol *kctl,
        return ret;
 }
 
+static int wm_coeff_put_acked(struct snd_kcontrol *kctl,
+                             struct snd_ctl_elem_value *ucontrol)
+{
+       struct soc_bytes_ext *bytes_ext =
+               (struct soc_bytes_ext *)kctl->private_value;
+       struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
+       unsigned int val = ucontrol->value.integer.value[0];
+       int ret;
+
+       if (val == 0)
+               return 0;       /* 0 means no event */
+
+       mutex_lock(&ctl->dsp->pwr_lock);
+
+       if (ctl->enabled)
+               ret = wm_coeff_write_acked_control(ctl, val);
+       else
+               ret = -EPERM;
+
+       mutex_unlock(&ctl->dsp->pwr_lock);
+
+       return ret;
+}
+
 static int wm_coeff_read_control(struct wm_coeff_ctl *ctl,
                                 void *buf, size_t len)
 {
@@ -1005,6 +1043,21 @@ static int wm_coeff_tlv_get(struct snd_kcontrol *kctl,
        return ret;
 }
 
+static int wm_coeff_get_acked(struct snd_kcontrol *kcontrol,
+                             struct snd_ctl_elem_value *ucontrol)
+{
+       /*
+        * Although it's not useful to read an acked control, we must satisfy
+        * user-side assumptions that all controls are readable and that a
+        * write of the same value should be filtered out (it's valid to send
+        * the same event number again to the firmware). We therefore return 0,
+        * meaning "no event" so valid event numbers will always be a change
+        */
+       ucontrol->value.integer.value[0] = 0;
+
+       return 0;
+}
+
 struct wmfw_ctl_work {
        struct wm_adsp *dsp;
        struct wm_coeff_ctl *ctl;
@@ -1057,17 +1110,25 @@ static int wmfw_add_ctl(struct wm_adsp *dsp, struct wm_coeff_ctl *ctl)
 
        kcontrol->name = ctl->name;
        kcontrol->info = wm_coeff_info;
-       kcontrol->get = wm_coeff_get;
-       kcontrol->put = wm_coeff_put;
        kcontrol->iface = SNDRV_CTL_ELEM_IFACE_MIXER;
        kcontrol->tlv.c = snd_soc_bytes_tlv_callback;
        kcontrol->private_value = (unsigned long)&ctl->bytes_ext;
+       kcontrol->access = wmfw_convert_flags(ctl->flags, ctl->len);
 
-       ctl->bytes_ext.max = ctl->len;
-       ctl->bytes_ext.get = wm_coeff_tlv_get;
-       ctl->bytes_ext.put = wm_coeff_tlv_put;
+       switch (ctl->type) {
+       case WMFW_CTL_TYPE_ACKED:
+               kcontrol->get = wm_coeff_get_acked;
+               kcontrol->put = wm_coeff_put_acked;
+               break;
+       default:
+               kcontrol->get = wm_coeff_get;
+               kcontrol->put = wm_coeff_put;
 
-       kcontrol->access = wmfw_convert_flags(ctl->flags, ctl->len);
+               ctl->bytes_ext.max = ctl->len;
+               ctl->bytes_ext.get = wm_coeff_tlv_get;
+               ctl->bytes_ext.put = wm_coeff_tlv_put;
+               break;
+       }
 
        ret = snd_soc_add_card_controls(dsp->card, kcontrol, 1);
        if (ret < 0)
@@ -1429,6 +1490,18 @@ static int wm_adsp_parse_coeff(struct wm_adsp *dsp,
                switch (coeff_blk.ctl_type) {
                case SNDRV_CTL_ELEM_TYPE_BYTES:
                        break;
+               case WMFW_CTL_TYPE_ACKED:
+                       if (coeff_blk.flags & WMFW_CTL_FLAG_SYS)
+                               continue;       /* ignore */
+
+                       ret = wm_adsp_check_coeff_flags(dsp, &coeff_blk,
+                                               WMFW_CTL_FLAG_VOLATILE |
+                                               WMFW_CTL_FLAG_WRITEABLE |
+                                               WMFW_CTL_FLAG_READABLE,
+                                               0);
+                       if (ret)
+                               return -EINVAL;
+                       break;
                case WMFW_CTL_TYPE_HOSTEVENT:
                        ret = wm_adsp_check_coeff_flags(dsp, &coeff_blk,
                                                WMFW_CTL_FLAG_SYS |

diff --git a/sound/soc/codecs/wmfw.h b/sound/soc/codecs/wmfw.h
index 892fc7490f3bd7a035e13e7a63cd1e3bd8ca71d1..ec78b9da020fb169be6e8f7d84285efd39a0df58 100644 (file)
--- a/sound/soc/codecs/wmfw.h
+++ b/sound/soc/codecs/wmfw.h
@@ -27,6 +27,7 @@
 #define WMFW_CTL_FLAG_READABLE    0x0001
 
 /* Non-ALSA coefficient types start at 0x1000 */
+#define WMFW_CTL_TYPE_ACKED       0x1000 /* acked control */
 #define WMFW_CTL_TYPE_HOSTEVENT   0x1001 /* event control */
 
 struct wmfw_header {