summaryrefslogtreecommitdiffstats
path: root/arch/arm/mach-davinci/cdce949.c
blob: aec375690543ee1e06dde197f50bbd2ee7d8cfef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
/*
 * 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");