[alsa-devel] [PATCH] ASoC: rl6231: get better PLL parameters
For those which can only get approximation PLL out cases, this patch will use higher resolution to get a better PLL parameter.
Signed-off-by: Bard Liao bardliao@realtek.com --- sound/soc/codecs/rl6231.c | 95 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 66 insertions(+), 29 deletions(-)
diff --git a/sound/soc/codecs/rl6231.c b/sound/soc/codecs/rl6231.c index 974a904..33690e9 100644 --- a/sound/soc/codecs/rl6231.c +++ b/sound/soc/codecs/rl6231.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/regmap.h>
+#include <linux/gcd.h> #include "rl6231.h"
/** @@ -106,6 +107,25 @@ static const struct pll_calc_map pll_preset_table[] = { {19200000, 24576000, 3, 30, 3, false}, };
+static unsigned int find_best_div(unsigned int in, + unsigned int max, unsigned int div) +{ + unsigned int d; + + if (in <= max) + return 1; + + d = in / max; + if (in % max) + d++; + + while (div % d != 0) + d++; + + + return d; +} + /** * rl6231_pll_calc - Calcualte PLL M/N/K code. * @freq_in: external clock provided to codec. @@ -120,9 +140,11 @@ int rl6231_pll_calc(const unsigned int freq_in, const unsigned int freq_out, struct rl6231_pll_code *pll_code) { int max_n = RL6231_PLL_N_MAX, max_m = RL6231_PLL_M_MAX; - int i, k, red, n_t, pll_out, in_t, out_t; - int n = 0, m = 0, m_t = 0; - int red_t = abs(freq_out - freq_in); + int i, k, n_t; + int k_t, min_k, max_k, n = 0, m = 0, m_t = 0; + unsigned int red, pll_out, in_t, out_t, div, div_t; + unsigned int red_t = abs(freq_out - freq_in); + unsigned int f_in, f_out, f_max; bool bypass = false;
if (RL6231_PLL_INP_MAX < freq_in || RL6231_PLL_INP_MIN > freq_in) @@ -140,39 +162,54 @@ int rl6231_pll_calc(const unsigned int freq_in, } }
- k = 100000000 / freq_out - 2; - if (k > RL6231_PLL_K_MAX) - k = RL6231_PLL_K_MAX; - for (n_t = 0; n_t <= max_n; n_t++) { - in_t = freq_in / (k + 2); - pll_out = freq_out / (n_t + 2); - if (in_t < 0) - continue; - if (in_t == pll_out) { - bypass = true; - n = n_t; - goto code_find; - } - red = abs(in_t - pll_out); - if (red < red_t) { - bypass = true; - n = n_t; - m = m_t; - if (red == 0) + min_k = 80000000 / freq_out - 2; + max_k = 150000000 / freq_out - 2; + if (max_k > RL6231_PLL_K_MAX) + max_k = RL6231_PLL_K_MAX; + if (min_k > RL6231_PLL_K_MAX) + min_k = max_k = RL6231_PLL_K_MAX; + div_t = gcd(freq_in, freq_out); + f_max = 0xffffffff / RL6231_PLL_N_MAX; + div = find_best_div(freq_in, f_max, div_t); + f_in = freq_in / div; + f_out = freq_out / div; + k = min_k; + for (k_t = min_k; k_t <= max_k; k_t++) { + for (n_t = 0; n_t <= max_n; n_t++) { + in_t = f_in * (n_t + 2); + pll_out = f_out * (k_t + 2); + if (in_t < 0) + continue; + if (in_t == pll_out) { + bypass = true; + n = n_t; + k = k_t; goto code_find; - red_t = red; - } - for (m_t = 0; m_t <= max_m; m_t++) { - out_t = in_t / (m_t + 2); - red = abs(out_t - pll_out); + } + out_t = in_t / (k_t + 2); + red = abs(f_out - out_t); if (red < red_t) { - bypass = false; + bypass = true; n = n_t; - m = m_t; + m = 0; + k = k_t; if (red == 0) goto code_find; red_t = red; } + for (m_t = 0; m_t <= max_m; m_t++) { + out_t = in_t / ((m_t + 2) * (k_t + 2)); + red = abs(f_out - out_t); + if (red < red_t) { + bypass = false; + n = n_t; + m = m_t; + k = k_t; + if (red == 0) + goto code_find; + red_t = red; + } + } } } pr_debug("Only get approximation about PLL\n");
The patch
ASoC: rl6231: get better PLL parameters
has been applied to the asoc tree at
https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound.git
All being well this means that it will be integrated into the linux-next tree (usually sometime in the next 24 hours) and sent to Linus during the next merge window (or sooner if it is a bug fix), however if problems are discovered then the patch may be dropped or reverted.
You may get further e-mails resulting from automated or manual testing and review of the tree, please engage with people reporting problems and send followup patches addressing any issues that are reported if needed.
If any updates are required or you are submitting further changes they should be sent as incremental updates against current git, existing patches will not be replaced.
Please add any relevant lists and maintainers to the CCs when replying to this mail.
Thanks, Mark
From 2f8aab3d29fda158fa49ecae94b3b3a4b494909d Mon Sep 17 00:00:00 2001
From: Bard Liao bardliao@realtek.com Date: Mon, 27 Nov 2017 20:03:14 +0800 Subject: [PATCH] ASoC: rl6231: get better PLL parameters
For those which can only get approximation PLL out cases, this patch will use higher resolution to get a better PLL parameter.
Signed-off-by: Bard Liao bardliao@realtek.com Signed-off-by: Mark Brown broonie@kernel.org --- sound/soc/codecs/rl6231.c | 95 ++++++++++++++++++++++++++++++++--------------- 1 file changed, 66 insertions(+), 29 deletions(-)
diff --git a/sound/soc/codecs/rl6231.c b/sound/soc/codecs/rl6231.c index 974a9040651d..33690e98e297 100644 --- a/sound/soc/codecs/rl6231.c +++ b/sound/soc/codecs/rl6231.c @@ -13,6 +13,7 @@ #include <linux/module.h> #include <linux/regmap.h>
+#include <linux/gcd.h> #include "rl6231.h"
/** @@ -106,6 +107,25 @@ static const struct pll_calc_map pll_preset_table[] = { {19200000, 24576000, 3, 30, 3, false}, };
+static unsigned int find_best_div(unsigned int in, + unsigned int max, unsigned int div) +{ + unsigned int d; + + if (in <= max) + return 1; + + d = in / max; + if (in % max) + d++; + + while (div % d != 0) + d++; + + + return d; +} + /** * rl6231_pll_calc - Calcualte PLL M/N/K code. * @freq_in: external clock provided to codec. @@ -120,9 +140,11 @@ int rl6231_pll_calc(const unsigned int freq_in, const unsigned int freq_out, struct rl6231_pll_code *pll_code) { int max_n = RL6231_PLL_N_MAX, max_m = RL6231_PLL_M_MAX; - int i, k, red, n_t, pll_out, in_t, out_t; - int n = 0, m = 0, m_t = 0; - int red_t = abs(freq_out - freq_in); + int i, k, n_t; + int k_t, min_k, max_k, n = 0, m = 0, m_t = 0; + unsigned int red, pll_out, in_t, out_t, div, div_t; + unsigned int red_t = abs(freq_out - freq_in); + unsigned int f_in, f_out, f_max; bool bypass = false;
if (RL6231_PLL_INP_MAX < freq_in || RL6231_PLL_INP_MIN > freq_in) @@ -140,39 +162,54 @@ int rl6231_pll_calc(const unsigned int freq_in, } }
- k = 100000000 / freq_out - 2; - if (k > RL6231_PLL_K_MAX) - k = RL6231_PLL_K_MAX; - for (n_t = 0; n_t <= max_n; n_t++) { - in_t = freq_in / (k + 2); - pll_out = freq_out / (n_t + 2); - if (in_t < 0) - continue; - if (in_t == pll_out) { - bypass = true; - n = n_t; - goto code_find; - } - red = abs(in_t - pll_out); - if (red < red_t) { - bypass = true; - n = n_t; - m = m_t; - if (red == 0) + min_k = 80000000 / freq_out - 2; + max_k = 150000000 / freq_out - 2; + if (max_k > RL6231_PLL_K_MAX) + max_k = RL6231_PLL_K_MAX; + if (min_k > RL6231_PLL_K_MAX) + min_k = max_k = RL6231_PLL_K_MAX; + div_t = gcd(freq_in, freq_out); + f_max = 0xffffffff / RL6231_PLL_N_MAX; + div = find_best_div(freq_in, f_max, div_t); + f_in = freq_in / div; + f_out = freq_out / div; + k = min_k; + for (k_t = min_k; k_t <= max_k; k_t++) { + for (n_t = 0; n_t <= max_n; n_t++) { + in_t = f_in * (n_t + 2); + pll_out = f_out * (k_t + 2); + if (in_t < 0) + continue; + if (in_t == pll_out) { + bypass = true; + n = n_t; + k = k_t; goto code_find; - red_t = red; - } - for (m_t = 0; m_t <= max_m; m_t++) { - out_t = in_t / (m_t + 2); - red = abs(out_t - pll_out); + } + out_t = in_t / (k_t + 2); + red = abs(f_out - out_t); if (red < red_t) { - bypass = false; + bypass = true; n = n_t; - m = m_t; + m = 0; + k = k_t; if (red == 0) goto code_find; red_t = red; } + for (m_t = 0; m_t <= max_m; m_t++) { + out_t = in_t / ((m_t + 2) * (k_t + 2)); + red = abs(f_out - out_t); + if (red < red_t) { + bypass = false; + n = n_t; + m = m_t; + k = k_t; + if (red == 0) + goto code_find; + red_t = red; + } + } } } pr_debug("Only get approximation about PLL\n");
participants (2)
-
Bard Liao -
Mark Brown