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
--- /dev/null
+++ b/sound/soc/codecs/rl6231.c
@@ -0,0 +1,133 @@
+/*
+ * 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");