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-rw-r--r--sound/soc/codecs/rl6231.c133
1 files changed, 133 insertions, 0 deletions
diff --git a/sound/soc/codecs/rl6231.c b/sound/soc/codecs/rl6231.c
new file mode 100644
index 000000000..56650d6c2
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+++ b/sound/soc/codecs/rl6231.c
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+/*
+ * rl6231.c - RL6231 class device shared support
+ *
+ * Copyright 2014 Realtek Semiconductor Corp.
+ *
+ * Author: Oder Chiou <oder_chiou@realtek.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/module.h>
+
+#include "rl6231.h"
+
+/**
+ * rl6231_calc_dmic_clk - Calculate the parameter of dmic.
+ *
+ * @rate: base clock rate.
+ *
+ * Choose dmic clock between 1MHz and 3MHz.
+ * It is better for clock to approximate 3MHz.
+ */
+int rl6231_calc_dmic_clk(int rate)
+{
+ int div[] = {2, 3, 4, 6, 8, 12}, idx = -EINVAL;
+ int i, red, bound, temp;
+
+ red = 3000000 * 12;
+ for (i = 0; i < ARRAY_SIZE(div); i++) {
+ bound = div[i] * 3000000;
+ if (rate > bound)
+ continue;
+ temp = bound - rate;
+ if (temp < red) {
+ red = temp;
+ idx = i;
+ }
+ }
+
+ return idx;
+}
+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);
+
+int rl6231_get_clk_info(int sclk, int rate)
+{
+ int i, pd[] = {1, 2, 3, 4, 6, 8, 12, 16};
+
+ if (sclk <= 0 || rate <= 0)
+ return -EINVAL;
+
+ rate = rate << 8;
+ for (i = 0; i < ARRAY_SIZE(pd); i++)
+ if (sclk == rate * pd[i])
+ return i;
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(rl6231_get_clk_info);
+
+MODULE_DESCRIPTION("RL6231 class device shared support");
+MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
+MODULE_LICENSE("GPL v2");