For some platforms where DA7219 is the DAI clock master, BCLK/WCLK
will be set and enabled prior to the codec's hw_params() function
being called. It is possible the platform requires a different
BCLK configuration than would be chosen by hw_params(), for
example S16_LE format needed with a 64-bit frame to satisfy certain
devices using the clocks.
To handle those kinds of scenarios, the use of clk_round_rate() is
now employed as part of hw_params(). If BCLK is already enabled
then this function will just return the currently set rate, if it
is valid for the desired frame size, so the subsequent call to
clk_set_rate() will succeed and nothing changes with regards to
clocking. In addition the specific BCLK & WCLK recalc_rate()
implementations needed updating to always give back a real value,
as those functions are called as part of the clk init code and a
real value is needed for the clk_round_rate() call to work as
expected.
Signed-off-by: Adam Thomson <Adam.Thomson.Opensource@xxxxxxxxxxx>
---
Changes in v2:
- Removed clk_round_rate() call for WCLK/SR as this is not sensible.
- Added checking after clk_round_rate() call for BCLK to verify returne rate is
suitable for the hw_params() desired frame size.
sound/soc/codecs/da7219.c | 21 +++++++++++++++------
1 file changed, 15 insertions(+), 6 deletions(-)
diff --git a/sound/soc/codecs/da7219.c b/sound/soc/codecs/da7219.c
index 5f5fa34..206d01c 100644
--- a/sound/soc/codecs/da7219.c
+++ b/sound/soc/codecs/da7219.c
@@ -1621,6 +1621,21 @@ static int da7219_hw_params(struct snd_pcm_substream *substream,
if (bclk) {
bclk_rate = frame_size * sr;
+ /*
+ * Rounding the rate here avoids failure trying to set a
+ * new rate on an already enabled bclk. In that
+ * instance this will just set the same rate as is
+ * currently in use, and so should continue without
+ * problem, as long as the BCLK rate is suitable for the
+ * desired frame size.
+ */
+ bclk_rate = clk_round_rate(bclk, bclk_rate);
+ if ((bclk_rate / sr) < frame_size) {
+ dev_err(component->dev,
+ "BCLK rate mismatch against frame size");
+ return -EINVAL;
+ }
+
ret = clk_set_rate(bclk, bclk_rate);
if (ret) {
dev_err(component->dev,
@@ -1927,9 +1942,6 @@ static unsigned long da7219_wclk_recalc_rate(struct clk_hw *hw,
struct snd_soc_component *component = da7219->component;
u8 fs = snd_soc_component_read32(component, DA7219_SR);
- if (!da7219->master)
- return 0;
-
switch (fs & DA7219_SR_MASK) {
case DA7219_SR_8000:
return 8000;
@@ -2016,9 +2028,6 @@ static unsigned long da7219_bclk_recalc_rate(struct clk_hw *hw,
u8 bclks_per_wclk = snd_soc_component_read32(component,
DA7219_DAI_CLK_MODE);
- if (!da7219->master)
- return 0;
-
switch (bclks_per_wclk & DA7219_DAI_BCLKS_PER_WCLK_MASK) {
case DA7219_DAI_BCLKS_PER_WCLK_32:
return parent_rate * 32;
--
1.9.1
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