According to RM, the clock divider range is from 1 to 8, clock prescaling ratio may be any power of 2 from 1 to 128. So the supported divider is not all the value between 1 and 1024, just limited value in that range.
Create table for the supported divder and add function to check the clock divider is available by comparing with the table.
Fixes: d0250cf4f2ab ("ASoC: fsl_asrc: Add an option to select internal ratio mode") Signed-off-by: Shengjiu Wang shengjiu.wang@nxp.com --- sound/soc/fsl/fsl_asrc.c | 69 +++++++++++++++++++++++++++++++++------- 1 file changed, 58 insertions(+), 11 deletions(-)
diff --git a/sound/soc/fsl/fsl_asrc.c b/sound/soc/fsl/fsl_asrc.c index 24b41881a68f..d7d1536a4f37 100644 --- a/sound/soc/fsl/fsl_asrc.c +++ b/sound/soc/fsl/fsl_asrc.c @@ -19,6 +19,7 @@ #include "fsl_asrc.h"
#define IDEAL_RATIO_DECIMAL_DEPTH 26 +#define DIVIDER_NUM 64
#define pair_err(fmt, ...) \ dev_err(&asrc->pdev->dev, "Pair %c: " fmt, 'A' + index, ##__VA_ARGS__) @@ -101,6 +102,55 @@ static unsigned char clk_map_imx8qxp[2][ASRC_CLK_MAP_LEN] = { }, };
+/* + * According to RM, the divider range is 1 ~ 8, + * prescaler is power of 2 from 1 ~ 128. + */ +static int asrc_clk_divider[DIVIDER_NUM] = { + 1, 2, 4, 8, 16, 32, 64, 128, /* divider = 1 */ + 2, 4, 8, 16, 32, 64, 128, 256, /* divider = 2 */ + 3, 6, 12, 24, 48, 96, 192, 384, /* divider = 3 */ + 4, 8, 16, 32, 64, 128, 256, 512, /* divider = 4 */ + 5, 10, 20, 40, 80, 160, 320, 640, /* divider = 5 */ + 6, 12, 24, 48, 96, 192, 384, 768, /* divider = 6 */ + 7, 14, 28, 56, 112, 224, 448, 896, /* divider = 7 */ + 8, 16, 32, 64, 128, 256, 512, 1024, /* divider = 8 */ +}; + +/* + * Check if the divider is available for internal ratio mode + */ +static bool fsl_asrc_divider_avail(int clk_rate, int rate, int *div) +{ + u32 rem, i; + u64 n; + + if (div) + *div = 0; + + if (clk_rate == 0 || rate == 0) + return false; + + n = clk_rate; + rem = do_div(n, rate); + + if (div) + *div = n; + + if (rem != 0) + return false; + + for (i = 0; i < DIVIDER_NUM; i++) { + if (n == asrc_clk_divider[i]) + break; + } + + if (i == DIVIDER_NUM) + return false; + + return true; +} + /** * fsl_asrc_sel_proc - Select the pre-processing and post-processing options * @inrate: input sample rate @@ -330,12 +380,12 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair, bool use_ideal_rate) enum asrc_word_width input_word_width; enum asrc_word_width output_word_width; u32 inrate, outrate, indiv, outdiv; - u32 clk_index[2], div[2], rem[2]; + u32 clk_index[2], div[2]; u64 clk_rate; int in, out, channels; int pre_proc, post_proc; struct clk *clk; - bool ideal; + bool ideal, div_avail;
if (!config) { pair_err("invalid pair config\n"); @@ -415,8 +465,7 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair, bool use_ideal_rate) clk = asrc_priv->asrck_clk[clk_index[ideal ? OUT : IN]];
clk_rate = clk_get_rate(clk); - rem[IN] = do_div(clk_rate, inrate); - div[IN] = (u32)clk_rate; + div_avail = fsl_asrc_divider_avail(clk_rate, inrate, &div[IN]);
/* * The divider range is [1, 1024], defined by the hardware. For non- @@ -425,7 +474,7 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair, bool use_ideal_rate) * only result in different converting speeds. So remainder does not * matter, as long as we keep the divider within its valid range. */ - if (div[IN] == 0 || (!ideal && (div[IN] > 1024 || rem[IN] != 0))) { + if (div[IN] == 0 || (!ideal && !div_avail)) { pair_err("failed to support input sample rate %dHz by asrck_%x\n", inrate, clk_index[ideal ? OUT : IN]); return -EINVAL; @@ -436,13 +485,12 @@ static int fsl_asrc_config_pair(struct fsl_asrc_pair *pair, bool use_ideal_rate) clk = asrc_priv->asrck_clk[clk_index[OUT]]; clk_rate = clk_get_rate(clk); if (ideal && use_ideal_rate) - rem[OUT] = do_div(clk_rate, IDEAL_RATIO_RATE); + div_avail = fsl_asrc_divider_avail(clk_rate, IDEAL_RATIO_RATE, &div[OUT]); else - rem[OUT] = do_div(clk_rate, outrate); - div[OUT] = clk_rate; + div_avail = fsl_asrc_divider_avail(clk_rate, outrate, &div[OUT]);
/* Output divider has the same limitation as the input one */ - if (div[OUT] == 0 || (!ideal && (div[OUT] > 1024 || rem[OUT] != 0))) { + if (div[OUT] == 0 || (!ideal && !div_avail)) { pair_err("failed to support output sample rate %dHz by asrck_%x\n", outrate, clk_index[OUT]); return -EINVAL; @@ -621,8 +669,7 @@ static void fsl_asrc_select_clk(struct fsl_asrc_priv *asrc_priv, clk_index = asrc_priv->clk_map[j][i]; clk_rate = clk_get_rate(asrc_priv->asrck_clk[clk_index]); /* Only match a perfect clock source with no remainder */ - if (clk_rate != 0 && (clk_rate / rate[j]) <= 1024 && - (clk_rate % rate[j]) == 0) + if (fsl_asrc_divider_avail(clk_rate, rate[j], NULL)) break; }