Re: [PATCH] ASoC: DAPM: Add support for multi register mux

From: Lars-Peter Clausen
Date: Tue Apr 01 2014 - 03:47:48 EST

On 04/01/2014 08:21 AM, Arun Shamanna Lakshmi wrote:
Modify soc_enum struct to handle pointers for reg and mask. Add
dapm get and put APIs for multi register mux with one hot encoding.

Signed-off-by: Arun Shamanna Lakshmi <aruns@xxxxxxxxxx>
Signed-off-by: Songhee Baek <sbaek@xxxxxxxxxx>

Looks in my opinion much better than the previous version :) Just a few minor issues, comments inline

---
include/sound/soc-dapm.h | 10 ++++
include/sound/soc.h | 22 +++++--
sound/soc/soc-core.c | 12 ++--
sound/soc/soc-dapm.c | 143 +++++++++++++++++++++++++++++++++++++++++-----
4 files changed, 162 insertions(+), 25 deletions(-)

diff --git a/include/sound/soc-dapm.h b/include/sound/soc-dapm.h
index ef78f56..983b0ab 100644
--- a/include/sound/soc-dapm.h
+++ b/include/sound/soc-dapm.h
@@ -305,6 +305,12 @@ struct device;
.get = snd_soc_dapm_get_enum_double, \
.put = snd_soc_dapm_put_enum_double, \
.private_value = (unsigned long)&xenum }
+#define SOC_DAPM_ENUM_WIDE(xname, xenum) \

maybe just call it ENUM_ONEHOT, since it doesn't actually have to be more than one register.

[...]
diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index cd52d52..aba0094 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -2601,12 +2601,12 @@ int snd_soc_get_enum_double(struct snd_kcontrol *kcontrol,
unsigned int val, item;
unsigned int reg_val;

- reg_val = snd_soc_read(codec, e->reg);
- val = (reg_val >> e->shift_l) & e->mask;
+ reg_val = snd_soc_read(codec, e->reg[0]);
+ val = (reg_val >> e->shift_l) & e->mask[0];
item = snd_soc_enum_val_to_item(e, val);
ucontrol->value.enumerated.item[0] = item;
if (e->shift_l != e->shift_r) {
- val = (reg_val >> e->shift_l) & e->mask;
+ val = (reg_val >> e->shift_l) & e->mask[0];
item = snd_soc_enum_val_to_item(e, val);
ucontrol->value.enumerated.item[1] = item;
}
@@ -2636,15 +2636,15 @@ int snd_soc_put_enum_double(struct snd_kcontrol *kcontrol,
if (item[0] >= e->items)
return -EINVAL;
val = snd_soc_enum_item_to_val(e, item[0]) << e->shift_l;
- mask = e->mask << e->shift_l;
+ mask = e->mask[0] << e->shift_l;
if (e->shift_l != e->shift_r) {
if (item[1] >= e->items)
return -EINVAL;
val |= snd_soc_enum_item_to_val(e, item[1]) << e->shift_r;
- mask |= e->mask << e->shift_r;
+ mask |= e->mask[0] << e->shift_r;
}

- return snd_soc_update_bits_locked(codec, e->reg, mask, val);
+ return snd_soc_update_bits_locked(codec, e->reg[0], mask, val);
}
EXPORT_SYMBOL_GPL(snd_soc_put_enum_double);

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c
index c8a780d..4d2b35c 100644
--- a/sound/soc/soc-dapm.c
+++ b/sound/soc/soc-dapm.c
@@ -514,9 +514,9 @@ static int dapm_connect_mux(struct snd_soc_dapm_context *dapm,
unsigned int val, item;
int i;

- if (e->reg != SND_SOC_NOPM) {
- soc_widget_read(dest, e->reg, &val);
- val = (val >> e->shift_l) & e->mask;
+ if (e->reg[0] != SND_SOC_NOPM) {
+ soc_widget_read(dest, e->reg[0], &val);
+ val = (val >> e->shift_l) & e->mask[0];
item = snd_soc_enum_val_to_item(e, val);

This probably should handle the new enum type as well. You'll probably need some kind of flag in the struct to distinguish between the two enum types.

} else {
/* since a virtual mux has no backing registers to
[...]
/**
+ * snd_soc_dapm_get_enum_wide - dapm semi enumerated multiple registers

What's a semi-enumerated register?

+ * mixer get callback
+ * @kcontrol: mixer control
+ * @ucontrol: control element information
+ *
+ * Callback to get the value of a dapm semi enumerated multiple register mixer
+ * control.
+ *
+ * semi enumerated multiple registers mixer:
+ * the mixer has multiple registers to set the enumerated items. The enumerated
+ * items are referred as values.
+ * Can be used for handling bit field coded enumeration for example.
+ *
+ * Returns 0 for success.
+ */
+int snd_soc_dapm_get_enum_wide(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_soc_codec *codec = snd_soc_dapm_kcontrol_codec(kcontrol);
+ struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
+ unsigned int reg_val, val, bit_pos = 0, reg_idx;
+
+ for (reg_idx = 0; reg_idx < e->num_regs; reg_idx++) {
+ reg_val = snd_soc_read(codec, e->reg[reg_idx]);
+ val = reg_val & e->mask[reg_idx];
+ if (val != 0) {
+ bit_pos = ffs(val) + (e->reg_width * reg_idx);

Should be __ffs. __ffs returns the bits zero-indexed and ffs one-indexed. That will work better for cases where there is not additional value table necessary, since it means bit 1 maps to value 0.

+ break;
+ }
+ }
+
+ ucontrol->value.enumerated.item[0] =
+ snd_soc_enum_val_to_item(e, bit_pos);
+
+ return 0;
+}
[...]
+int snd_soc_dapm_put_enum_wide(struct snd_kcontrol *kcontrol,
+ struct snd_ctl_elem_value *ucontrol)
+{
+ struct snd_soc_codec *codec = snd_soc_dapm_kcontrol_codec(kcontrol);
+ struct snd_soc_card *card = codec->card;
+ struct soc_enum *e = (struct soc_enum *)kcontrol->private_value;
+ unsigned int *item = ucontrol->value.enumerated.item;
+ unsigned int change = 0, reg_idx = 0, value, bit_pos;
+ struct snd_soc_dapm_update update;
+ int ret = 0, reg_val = 0, i;
+
+ if (item[0] >= e->items)
+ return -EINVAL;
+
+ value = snd_soc_enum_item_to_val(e, item[0]);
+
+ if (value) {
+ /* get the register index and value to set */
+ reg_idx = (value - 1) / e->reg_width;
+ bit_pos = (value - 1) % e->reg_width;

Changing the ffs to __ffs also means you can drop the ' - 1' here.

Also e->reg_width should be (codec->val_bytes * 8) and reg_width field should be dropped from the enum struct.

+ reg_val = BIT(bit_pos);
+ }
+
+ for (i = 0; i < e->num_regs; i++) {
+ if (i == reg_idx) {
+ change = snd_soc_test_bits(codec, e->reg[i],
+ e->mask[i], reg_val);
+
+ } else {
+ /* accumulate the change to update the DAPM path
+ when none is selected */
+ change += snd_soc_test_bits(codec, e->reg[i],
+ e->mask[i], 0);

change |=

+
+ /* clear the register when not selected */
+ snd_soc_write(codec, e->reg[i], 0);

I think this should happen as part of the DAPM update sequence like you had earlier. Some special care should probably be take to make sure that you de-select the previous mux input before selecting the new one if the new one is in a different register than the previous one.

+ }
+ }
+
+ mutex_lock_nested(&card->dapm_mutex, SND_SOC_DAPM_CLASS_RUNTIME);
+
[...]

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/