On Thu, Jul 16, 2020 at 05:13:52PM +0200, Arnaud Ferraris wrote:
The current clock selection algorithm might select the same clock for both input and output. This can happen when, for instance, the output sample rate is a multiple of the input rate.
What's the issue when selecting the same clock source for both input and output? Please explain it in the commit logs.
This patch makes sure it always selects distinct input and output clocks.
Signed-off-by: Arnaud Ferraris arnaud.ferraris@collabora.com
sound/soc/fsl/fsl_asrc.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-)
diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c index 02c81d2e34ad..6d43cab6c885 100644 --- a/sound/soc/fsl/fsl_asrc.c +++ b/sound/soc/fsl/fsl_asrc.c @@ -608,8 +608,8 @@ static void fsl_asrc_select_clk(struct fsl_asrc_priv *asrc_priv, { struct fsl_asrc_pair_priv *pair_priv = pair->private; struct asrc_config *config = pair_priv->config;
- int rate[2], select_clk[2]; /* Array size 2 means IN and OUT */
- int clk_rate, clk_index;
int rate[2], select_clk[2], clk_index[2]; /* Array size 2 means IN and OUT */
int clk_rate; int i = 0, j = 0;
rate[IN] = in_rate;
@@ -618,11 +618,12 @@ static void fsl_asrc_select_clk(struct fsl_asrc_priv *asrc_priv, /* Select proper clock source for internal ratio mode */ for (j = 0; j < 2; j++) { for (i = 0; i < ASRC_CLK_MAP_LEN; i++) {
clk_index = asrc_priv->clk_map[j][i];clk_rate = clk_get_rate(asrc_priv->asrck_clk[clk_index]);
clk_index[j] = asrc_priv->clk_map[j][i];clk_rate = clk_get_rate(asrc_priv->asrck_clk[clk_index[j]]); /* Only match a perfect clock source with no remainder */
Better to update the comments here as there's a new condition.
if (clk_rate != 0 && (clk_rate / rate[j]) <= 1024 &&
(clk_rate % rate[j]) == 0)
(clk_rate % rate[j]) == 0 &&(j == 0 || clk_index[j] != clk_index[j-1]))
clk_index[j - 1]