xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ASoC: rt5640: Add the function of the PLL clock calculation to RL6231 shared support

Browse Source 
The patch adds the function of the PLL clock calculation to RL6231 shared
support.

Signed-off-by: Oder Chiou <oder_chiou@realtek.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
This commit is contained in:
Oder Chiou
2014-05-20 15:01:54 +08:00
committed by Mark Brown
parent 49ef7925c2
commit 71c7a2d675
8 changed files with 102 additions and 206 deletions
Download Patch File Download Diff File Expand all files Collapse all files

69
sound/soc/codecs/rl6231.c
View File

@@ -62,6 +62,75 @@ int rl6231_calc_dmic_clk(int rate)
}
EXPORT_SYMBOL_GPL(rl6231_calc_dmic_clk);
/**
* rl6231_pll_calc - Calcualte PLL M/N/K code.
* @freq_in: external clock provided to codec.
* @freq_out: target clock which codec works on.
* @pll_code: Pointer to structure with M, N, K and bypass flag.
*
* Calcualte M/N/K code to configure PLL for codec.
*
* Returns 0 for success or negative error code.
*/
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 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);
bool bypass = false;
if (RL6231_PLL_INP_MAX < freq_in || RL6231_PLL_INP_MIN > freq_in)
return -EINVAL;
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)
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);
if (red < red_t) {
bypass = false;
n = n_t;
m = m_t;
if (red == 0)
goto code_find;
red_t = red;
}
}
}
pr_debug("Only get approximation about PLL\n");
code_find:
pll_code->m_bp = bypass;
pll_code->m_code = m;
pll_code->n_code = n;
pll_code->k_code = k;
return 0;
}
EXPORT_SYMBOL_GPL(rl6231_pll_calc);
MODULE_DESCRIPTION("RL6231 class device shared support");
MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
MODULE_LICENSE("GPL v2");