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Diffstat (limited to 'sound/soc/stm/stm32_sai_sub.c')
-rw-r--r--sound/soc/stm/stm32_sai_sub.c16
1 files changed, 11 insertions, 5 deletions
diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c
index e8c1abf1ae0a..bf5299ba11c3 100644
--- a/sound/soc/stm/stm32_sai_sub.c
+++ b/sound/soc/stm/stm32_sai_sub.c
@@ -409,11 +409,11 @@ static int stm32_sai_set_parent_rate(struct stm32_sai_sub_data *sai,
unsigned int rate)
{
struct platform_device *pdev = sai->pdev;
- unsigned int sai_ck_rate, sai_ck_max_rate, sai_curr_rate, sai_new_rate;
+ unsigned int sai_ck_rate, sai_ck_max_rate, sai_ck_min_rate, sai_curr_rate, sai_new_rate;
int div, ret;
/*
- * Set maximum expected kernel clock frequency
+ * Set minimum and maximum expected kernel clock frequency
* - mclk on or spdif:
* f_sai_ck = MCKDIV * mclk-fs * fs
* Here typical 256 ratio is assumed for mclk-fs
@@ -423,13 +423,16 @@ static int stm32_sai_set_parent_rate(struct stm32_sai_sub_data *sai,
* Set constraint MCKDIV * FRL <= 256, to ensure MCKDIV is in available range
* f_sai_ck = sai_ck_max_rate * pow_of_two(FRL) / 256
*/
+ sai_ck_min_rate = rate * 256;
if (!(rate % SAI_RATE_11K))
sai_ck_max_rate = SAI_MAX_SAMPLE_RATE_11K * 256;
else
sai_ck_max_rate = SAI_MAX_SAMPLE_RATE_8K * 256;
- if (!sai->sai_mclk && !STM_SAI_PROTOCOL_IS_SPDIF(sai))
+ if (!sai->sai_mclk && !STM_SAI_PROTOCOL_IS_SPDIF(sai)) {
+ sai_ck_min_rate = rate * sai->fs_length;
sai_ck_max_rate /= DIV_ROUND_CLOSEST(256, roundup_pow_of_two(sai->fs_length));
+ }
/*
* Request exclusivity, as the clock is shared by SAI sub-blocks and by
@@ -444,7 +447,10 @@ static int stm32_sai_set_parent_rate(struct stm32_sai_sub_data *sai,
* return immediately.
*/
sai_curr_rate = clk_get_rate(sai->sai_ck);
- if (stm32_sai_rate_accurate(sai_ck_max_rate, sai_curr_rate))
+ dev_dbg(&pdev->dev, "kernel clock rate: min [%u], max [%u], current [%u]",
+ sai_ck_min_rate, sai_ck_max_rate, sai_curr_rate);
+ if (stm32_sai_rate_accurate(sai_ck_max_rate, sai_curr_rate) &&
+ sai_curr_rate >= sai_ck_min_rate)
return 0;
/*
@@ -472,7 +478,7 @@ static int stm32_sai_set_parent_rate(struct stm32_sai_sub_data *sai,
/* Try a lower frequency */
div++;
sai_ck_rate = sai_ck_max_rate / div;
- } while (sai_ck_rate > rate);
+ } while (sai_ck_rate >= sai_ck_min_rate);
/* No accurate rate found */
dev_err(&pdev->dev, "Failed to find an accurate rate");