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-rw-r--r--arch/arm/mach-davinci/cdce949.c293
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diff --git a/arch/arm/mach-davinci/cdce949.c b/arch/arm/mach-davinci/cdce949.c
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+/*
+ * TI CDCE949 clock synthesizer driver
+ *
+ * Note: This implementation assumes an input of 27MHz to the CDCE.
+ * This is by no means constrained by CDCE hardware although the datasheet
+ * does use this as an example for all illustrations and more importantly:
+ * that is the crystal input on boards it is currently used on.
+ *
+ * Copyright (C) 2009 Texas Instruments Incorporated. http://www.ti.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/kernel.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+
+#include <mach/clock.h>
+
+#include "clock.h"
+
+static struct i2c_client *cdce_i2c_client;
+static DEFINE_MUTEX(cdce_mutex);
+
+/* CDCE register descriptor */
+struct cdce_reg {
+ u8 addr;
+ u8 val;
+};
+
+/* Per-Output (Y1, Y2 etc.) frequency descriptor */
+struct cdce_freq {
+ /* Frequency in KHz */
+ unsigned long frequency;
+ /*
+ * List of registers to program to obtain a particular frequency.
+ * 0x0 in register address and value is the end of list marker.
+ */
+ struct cdce_reg *reglist;
+};
+
+#define CDCE_FREQ_TABLE_ENTRY(line, out) \
+{ \
+ .reglist = cdce_y ##line## _ ##out, \
+ .frequency = out, \
+}
+
+/* List of CDCE outputs */
+struct cdce_output {
+ /* List of frequencies on this output */
+ struct cdce_freq *freq_table;
+ /* Number of possible frequencies */
+ int size;
+};
+
+/*
+ * Finding out the values to program into CDCE949 registers for a particular
+ * frequency output is not a simple calculation. Have a look at the datasheet
+ * for the details. There is desktop software available to help users with
+ * the calculations. Here, we just depend on the output of that software
+ * (or hand calculations) instead trying to runtime calculate the register
+ * values and inflicting misery on ourselves.
+ */
+static struct cdce_reg cdce_y1_148500[] = {
+ { 0x13, 0x00 },
+ /* program PLL1_0 multiplier */
+ { 0x18, 0xaf },
+ { 0x19, 0x50 },
+ { 0x1a, 0x02 },
+ { 0x1b, 0xc9 },
+ /* program PLL1_11 multiplier */
+ { 0x1c, 0x00 },
+ { 0x1d, 0x40 },
+ { 0x1e, 0x02 },
+ { 0x1f, 0xc9 },
+ /* output state selection */
+ { 0x15, 0x00 },
+ { 0x14, 0xef },
+ /* switch MUX to PLL1 output */
+ { 0x14, 0x6f },
+ { 0x16, 0x06 },
+ /* set P2DIV divider, P3DIV and input crystal */
+ { 0x17, 0x06 },
+ { 0x01, 0x00 },
+ { 0x05, 0x48 },
+ { 0x02, 0x80 },
+ /* enable and disable PLL */
+ { 0x02, 0xbc },
+ { 0x03, 0x01 },
+ { },
+};
+
+static struct cdce_reg cdce_y1_74250[] = {
+ { 0x13, 0x00 },
+ { 0x18, 0xaf },
+ { 0x19, 0x50 },
+ { 0x1a, 0x02 },
+ { 0x1b, 0xc9 },
+ { 0x1c, 0x00 },
+ { 0x1d, 0x40 },
+ { 0x1e, 0x02 },
+ { 0x1f, 0xc9 },
+ /* output state selection */
+ { 0x15, 0x00 },
+ { 0x14, 0xef },
+ /* switch MUX to PLL1 output */
+ { 0x14, 0x6f },
+ { 0x16, 0x06 },
+ /* set P2DIV divider, P3DIV and input crystal */
+ { 0x17, 0x06 },
+ { 0x01, 0x00 },
+ { 0x05, 0x48 },
+ { 0x02, 0x80 },
+ /* enable and disable PLL */
+ { 0x02, 0xbc },
+ { 0x03, 0x02 },
+ { },
+};
+
+static struct cdce_reg cdce_y1_27000[] = {
+ { 0x13, 0x00 },
+ { 0x18, 0x00 },
+ { 0x19, 0x40 },
+ { 0x1a, 0x02 },
+ { 0x1b, 0x08 },
+ { 0x1c, 0x00 },
+ { 0x1d, 0x40 },
+ { 0x1e, 0x02 },
+ { 0x1f, 0x08 },
+ { 0x15, 0x02 },
+ { 0x14, 0xed },
+ { 0x16, 0x01 },
+ { 0x17, 0x01 },
+ { 0x01, 0x00 },
+ { 0x05, 0x50 },
+ { 0x02, 0xb4 },
+ { 0x03, 0x01 },
+ { },
+};
+
+static struct cdce_freq cdce_y1_freqs[] = {
+ CDCE_FREQ_TABLE_ENTRY(1, 148500),
+ CDCE_FREQ_TABLE_ENTRY(1, 74250),
+ CDCE_FREQ_TABLE_ENTRY(1, 27000),
+};
+
+static struct cdce_reg cdce_y5_13500[] = {
+ { 0x27, 0x08 },
+ { 0x28, 0x00 },
+ { 0x29, 0x40 },
+ { 0x2a, 0x02 },
+ { 0x2b, 0x08 },
+ { 0x24, 0x6f },
+ { },
+};
+
+static struct cdce_reg cdce_y5_16875[] = {
+ { 0x27, 0x08 },
+ { 0x28, 0x9f },
+ { 0x29, 0xb0 },
+ { 0x2a, 0x02 },
+ { 0x2b, 0x89 },
+ { 0x24, 0x6f },
+ { },
+};
+
+static struct cdce_reg cdce_y5_27000[] = {
+ { 0x27, 0x04 },
+ { 0x28, 0x00 },
+ { 0x29, 0x40 },
+ { 0x2a, 0x02 },
+ { 0x2b, 0x08 },
+ { 0x24, 0x6f },
+ { },
+};
+static struct cdce_reg cdce_y5_54000[] = {
+ { 0x27, 0x04 },
+ { 0x28, 0xff },
+ { 0x29, 0x80 },
+ { 0x2a, 0x02 },
+ { 0x2b, 0x07 },
+ { 0x24, 0x6f },
+ { },
+};
+
+static struct cdce_reg cdce_y5_81000[] = {
+ { 0x27, 0x02 },
+ { 0x28, 0xbf },
+ { 0x29, 0xa0 },
+ { 0x2a, 0x03 },
+ { 0x2b, 0x0a },
+ { 0x24, 0x6f },
+ { },
+};
+
+static struct cdce_freq cdce_y5_freqs[] = {
+ CDCE_FREQ_TABLE_ENTRY(5, 13500),
+ CDCE_FREQ_TABLE_ENTRY(5, 16875),
+ CDCE_FREQ_TABLE_ENTRY(5, 27000),
+ CDCE_FREQ_TABLE_ENTRY(5, 54000),
+ CDCE_FREQ_TABLE_ENTRY(5, 81000),
+};
+
+
+static struct cdce_output output_list[] = {
+ [1] = { cdce_y1_freqs, ARRAY_SIZE(cdce_y1_freqs) },
+ [5] = { cdce_y5_freqs, ARRAY_SIZE(cdce_y5_freqs) },
+};
+
+int cdce_set_rate(struct clk *clk, unsigned long rate)
+{
+ int i, ret = 0;
+ struct cdce_freq *freq_table = output_list[clk->lpsc].freq_table;
+ struct cdce_reg *regs = NULL;
+
+ if (!cdce_i2c_client)
+ return -ENODEV;
+
+ if (!freq_table)
+ return -EINVAL;
+
+ for (i = 0; i < output_list[clk->lpsc].size; i++) {
+ if (freq_table[i].frequency == rate / 1000) {
+ regs = freq_table[i].reglist;
+ break;
+ }
+ }
+
+ if (!regs)
+ return -EINVAL;
+
+ mutex_lock(&cdce_mutex);
+ for (i = 0; regs[i].addr; i++) {
+ ret = i2c_smbus_write_byte_data(cdce_i2c_client,
+ regs[i].addr | 0x80, regs[i].val);
+ if (ret)
+ break;
+ }
+ mutex_unlock(&cdce_mutex);
+
+ if (!ret)
+ clk->rate = rate;
+
+ return ret;
+}
+
+static int cdce_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ cdce_i2c_client = client;
+ return 0;
+}
+
+static int __devexit cdce_remove(struct i2c_client *client)
+{
+ cdce_i2c_client = NULL;
+ return 0;
+}
+
+static const struct i2c_device_id cdce_id[] = {
+ {"cdce949", 0},
+ {},
+};
+MODULE_DEVICE_TABLE(i2c, cdce_id);
+
+static struct i2c_driver cdce_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "cdce949",
+ },
+ .probe = cdce_probe,
+ .remove = __devexit_p(cdce_remove),
+ .id_table = cdce_id,
+};
+
+static int __init cdce_init(void)
+{
+ return i2c_add_driver(&cdce_driver);
+}
+subsys_initcall(cdce_init);
+
+static void __exit cdce_exit(void)
+{
+ i2c_del_driver(&cdce_driver);
+}
+module_exit(cdce_exit);
+
+MODULE_AUTHOR("Texas Instruments");
+MODULE_DESCRIPTION("CDCE949 clock synthesizer driver");
+MODULE_LICENSE("GPL v2");