[alsa-devel] [PATCH] ASoC: wm_adsp: Add support for TLV based binary controls

[Charles Keepax]

This patch adds support for the arbitrary length TLV based binary
controls. This allows users to properly access controls that are
more than 512 bytes in length.

Signed-off-by: Charles Keepax <ckeepax at opensource.wolfsonmicro.com>
---
 sound/soc/codecs/wm_adsp.c | 128 ++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 108 insertions(+), 20 deletions(-)

diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c
index 5699a81..630ebcd 100644
--- a/sound/soc/codecs/wm_adsp.c
+++ b/sound/soc/codecs/wm_adsp.c
@@ -160,6 +160,8 @@
 #define ADSP2_RAM_RDY_SHIFT                    0
 #define ADSP2_RAM_RDY_WIDTH                    1
 
+#define ADSP_MAX_STD_CTRL_SIZE               512
+
 struct wm_adsp_buf {
 	struct list_head list;
 	void *buf;
@@ -435,6 +437,7 @@ struct wm_coeff_ctl {
 	size_t len;
 	unsigned int set:1;
 	struct snd_kcontrol *kcontrol;
+	struct soc_bytes_ext bytes_ext;
 	unsigned int flags;
 };
 
@@ -711,10 +714,17 @@ static void wm_adsp2_show_fw_status(struct wm_adsp *dsp)
 		 be16_to_cpu(scratch[3]));
 }
 
+static inline struct wm_coeff_ctl *bytes_ext_to_ctl(struct soc_bytes_ext *ext)
+{
+	return container_of(ext, struct wm_coeff_ctl, bytes_ext);
+}
+
 static int wm_coeff_info(struct snd_kcontrol *kctl,
 			 struct snd_ctl_elem_info *uinfo)
 {
-	struct wm_coeff_ctl *ctl = (struct wm_coeff_ctl *)kctl->private_value;
+	struct soc_bytes_ext *bytes_ext =
+		(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;
@@ -763,7 +773,9 @@ static int wm_coeff_write_control(struct wm_coeff_ctl *ctl,
 static int wm_coeff_put(struct snd_kcontrol *kctl,
 			struct snd_ctl_elem_value *ucontrol)
 {
-	struct wm_coeff_ctl *ctl = (struct wm_coeff_ctl *)kctl->private_value;
+	struct soc_bytes_ext *bytes_ext =
+		(struct soc_bytes_ext *)kctl->private_value;
+	struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
 	char *p = ucontrol->value.bytes.data;
 	int ret = 0;
 
@@ -780,6 +792,29 @@ static int wm_coeff_put(struct snd_kcontrol *kctl,
 	return ret;
 }
 
+static int wm_coeff_tlv_put(struct snd_kcontrol *kctl,
+			    const unsigned int __user *bytes, unsigned int size)
+{
+	struct soc_bytes_ext *bytes_ext =
+		(struct soc_bytes_ext *)kctl->private_value;
+	struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
+	int ret = 0;
+
+	mutex_lock(&ctl->dsp->pwr_lock);
+
+	if (copy_from_user(ctl->cache, bytes, size)) {
+		ret = -EFAULT;
+	} else {
+		ctl->set = 1;
+		if (ctl->enabled)
+			ret = wm_coeff_write_control(ctl, ctl->cache, size);
+	}
+
+	mutex_unlock(&ctl->dsp->pwr_lock);
+
+	return ret;
+}
+
 static int wm_coeff_read_control(struct wm_coeff_ctl *ctl,
 				 void *buf, size_t len)
 {
@@ -822,7 +857,9 @@ static int wm_coeff_read_control(struct wm_coeff_ctl *ctl,
 static int wm_coeff_get(struct snd_kcontrol *kctl,
 			struct snd_ctl_elem_value *ucontrol)
 {
-	struct wm_coeff_ctl *ctl = (struct wm_coeff_ctl *)kctl->private_value;
+	struct soc_bytes_ext *bytes_ext =
+		(struct soc_bytes_ext *)kctl->private_value;
+	struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
 	char *p = ucontrol->value.bytes.data;
 	int ret = 0;
 
@@ -845,12 +882,72 @@ static int wm_coeff_get(struct snd_kcontrol *kctl,
 	return ret;
 }
 
+static int wm_coeff_tlv_get(struct snd_kcontrol *kctl,
+			    unsigned int __user *bytes, unsigned int size)
+{
+	struct soc_bytes_ext *bytes_ext =
+		(struct soc_bytes_ext *)kctl->private_value;
+	struct wm_coeff_ctl *ctl = bytes_ext_to_ctl(bytes_ext);
+	int ret = 0;
+
+	mutex_lock(&ctl->dsp->pwr_lock);
+
+	if (ctl->flags & WMFW_CTL_FLAG_VOLATILE) {
+		if (ctl->enabled)
+			ret = wm_coeff_read_control(ctl, ctl->cache, size);
+		else
+			ret = -EPERM;
+	} else {
+		if (!ctl->flags && ctl->enabled)
+			ret = wm_coeff_read_control(ctl, ctl->cache, size);
+	}
+
+	if (!ret && copy_to_user(bytes, ctl->cache, size))
+		ret = -EFAULT;
+
+	mutex_unlock(&ctl->dsp->pwr_lock);
+
+	return ret;
+}
+
 struct wmfw_ctl_work {
 	struct wm_adsp *dsp;
 	struct wm_coeff_ctl *ctl;
 	struct work_struct work;
 };
 
+static unsigned int wmfw_convert_flags(unsigned int in, unsigned int len)
+{
+	unsigned int out, rd, wr, vol;
+
+	if (len > ADSP_MAX_STD_CTRL_SIZE) {
+		rd = SNDRV_CTL_ELEM_ACCESS_TLV_READ;
+		wr = SNDRV_CTL_ELEM_ACCESS_TLV_WRITE;
+		vol = SNDRV_CTL_ELEM_ACCESS_VOLATILE;
+
+		out = SNDRV_CTL_ELEM_ACCESS_TLV_CALLBACK;
+	} else {
+		rd = SNDRV_CTL_ELEM_ACCESS_READ;
+		wr = SNDRV_CTL_ELEM_ACCESS_WRITE;
+		vol = SNDRV_CTL_ELEM_ACCESS_VOLATILE;
+
+		out = 0;
+	}
+
+	if (in) {
+		if (in & WMFW_CTL_FLAG_READABLE)
+			out |= rd;
+		if (in & WMFW_CTL_FLAG_WRITEABLE)
+			out |= wr;
+		if (in & WMFW_CTL_FLAG_VOLATILE)
+			out |= vol;
+	} else {
+		out |= rd | wr | vol;
+	}
+
+	return out;
+}
+
 static int wmfw_add_ctl(struct wm_adsp *dsp, struct wm_coeff_ctl *ctl)
 {
 	struct snd_kcontrol_new *kcontrol;
@@ -868,19 +965,15 @@ static int wmfw_add_ctl(struct wm_adsp *dsp, struct wm_coeff_ctl *ctl)
 	kcontrol->info = wm_coeff_info;
 	kcontrol->get = wm_coeff_get;
 	kcontrol->put = wm_coeff_put;
-	kcontrol->private_value = (unsigned long)ctl;
+	kcontrol->iface = SNDRV_CTL_ELEM_IFACE_MIXER;
+	kcontrol->tlv.c = snd_soc_bytes_tlv_callback;
+	kcontrol->private_value = (unsigned long)&ctl->bytes_ext;
 
-	if (ctl->flags) {
-		if (ctl->flags & WMFW_CTL_FLAG_WRITEABLE)
-			kcontrol->access |= SNDRV_CTL_ELEM_ACCESS_WRITE;
-		if (ctl->flags & WMFW_CTL_FLAG_READABLE)
-			kcontrol->access |= SNDRV_CTL_ELEM_ACCESS_READ;
-		if (ctl->flags & WMFW_CTL_FLAG_VOLATILE)
-			kcontrol->access |= SNDRV_CTL_ELEM_ACCESS_VOLATILE;
-	} else {
-		kcontrol->access = SNDRV_CTL_ELEM_ACCESS_READWRITE;
-		kcontrol->access |= SNDRV_CTL_ELEM_ACCESS_VOLATILE;
-	}
+	ctl->bytes_ext.max = ctl->len;
+	ctl->bytes_ext.get = wm_coeff_tlv_get;
+	ctl->bytes_ext.put = wm_coeff_tlv_put;
+
+	kcontrol->access = wmfw_convert_flags(ctl->flags, ctl->len);
 
 	ret = snd_soc_add_card_controls(dsp->card, kcontrol, 1);
 	if (ret < 0)
@@ -1039,11 +1132,6 @@ static int wm_adsp_create_control(struct wm_adsp *dsp,
 
 	ctl->flags = flags;
 	ctl->offset = offset;
-	if (len > 512) {
-		adsp_warn(dsp, "Truncating control %s from %d\n",
-			  ctl->name, len);
-		len = 512;
-	}
 	ctl->len = len;
 	ctl->cache = kzalloc(ctl->len, GFP_KERNEL);
 	if (!ctl->cache) {
-- 
2.1.4