summaryrefslogtreecommitdiffstats
path: root/kernel/drivers/clk/at91/clk-usb.c
blob: 0b7c3e8840bae0ebf2c97cf276e44e8ab7116f6e (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
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
/*
 *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 */

#include <linux/clk-provider.h>
#include <linux/clkdev.h>
#include <linux/clk/at91_pmc.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/io.h>

#include "pmc.h"

#define USB_SOURCE_MAX		2

#define SAM9X5_USB_DIV_SHIFT	8
#define SAM9X5_USB_MAX_DIV	0xf

#define RM9200_USB_DIV_SHIFT	28
#define RM9200_USB_DIV_TAB_SIZE	4

struct at91sam9x5_clk_usb {
	struct clk_hw hw;
	struct at91_pmc *pmc;
};

#define to_at91sam9x5_clk_usb(hw) \
	container_of(hw, struct at91sam9x5_clk_usb, hw)

struct at91rm9200_clk_usb {
	struct clk_hw hw;
	struct at91_pmc *pmc;
	u32 divisors[4];
};

#define to_at91rm9200_clk_usb(hw) \
	container_of(hw, struct at91rm9200_clk_usb, hw)

static unsigned long at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw,
						    unsigned long parent_rate)
{
	u32 tmp;
	u8 usbdiv;
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;

	tmp = pmc_read(pmc, AT91_PMC_USB);
	usbdiv = (tmp & AT91_PMC_OHCIUSBDIV) >> SAM9X5_USB_DIV_SHIFT;

	return DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1));
}

static long at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw,
					      unsigned long rate,
					      unsigned long min_rate,
					      unsigned long max_rate,
					      unsigned long *best_parent_rate,
					      struct clk_hw **best_parent_hw)
{
	struct clk *parent = NULL;
	long best_rate = -EINVAL;
	unsigned long tmp_rate;
	int best_diff = -1;
	int tmp_diff;
	int i;

	for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
		int div;

		parent = clk_get_parent_by_index(hw->clk, i);
		if (!parent)
			continue;

		for (div = 1; div < SAM9X5_USB_MAX_DIV + 2; div++) {
			unsigned long tmp_parent_rate;

			tmp_parent_rate = rate * div;
			tmp_parent_rate = __clk_round_rate(parent,
							   tmp_parent_rate);
			tmp_rate = DIV_ROUND_CLOSEST(tmp_parent_rate, div);
			if (tmp_rate < rate)
				tmp_diff = rate - tmp_rate;
			else
				tmp_diff = tmp_rate - rate;

			if (best_diff < 0 || best_diff > tmp_diff) {
				best_rate = tmp_rate;
				best_diff = tmp_diff;
				*best_parent_rate = tmp_parent_rate;
				*best_parent_hw = __clk_get_hw(parent);
			}

			if (!best_diff || tmp_rate < rate)
				break;
		}

		if (!best_diff)
			break;
	}

	return best_rate;
}

static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index)
{
	u32 tmp;
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;

	if (index > 1)
		return -EINVAL;
	tmp = pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_USBS;
	if (index)
		tmp |= AT91_PMC_USBS;
	pmc_write(pmc, AT91_PMC_USB, tmp);
	return 0;
}

static u8 at91sam9x5_clk_usb_get_parent(struct clk_hw *hw)
{
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;

	return pmc_read(pmc, AT91_PMC_USB) & AT91_PMC_USBS;
}

static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
				       unsigned long parent_rate)
{
	u32 tmp;
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;
	unsigned long div;

	if (!rate)
		return -EINVAL;

	div = DIV_ROUND_CLOSEST(parent_rate, rate);
	if (div > SAM9X5_USB_MAX_DIV + 1 || !div)
		return -EINVAL;

	tmp = pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_OHCIUSBDIV;
	tmp |= (div - 1) << SAM9X5_USB_DIV_SHIFT;
	pmc_write(pmc, AT91_PMC_USB, tmp);

	return 0;
}

static const struct clk_ops at91sam9x5_usb_ops = {
	.recalc_rate = at91sam9x5_clk_usb_recalc_rate,
	.determine_rate = at91sam9x5_clk_usb_determine_rate,
	.get_parent = at91sam9x5_clk_usb_get_parent,
	.set_parent = at91sam9x5_clk_usb_set_parent,
	.set_rate = at91sam9x5_clk_usb_set_rate,
};

static int at91sam9n12_clk_usb_enable(struct clk_hw *hw)
{
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;

	pmc_write(pmc, AT91_PMC_USB,
		  pmc_read(pmc, AT91_PMC_USB) | AT91_PMC_USBS);
	return 0;
}

static void at91sam9n12_clk_usb_disable(struct clk_hw *hw)
{
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;

	pmc_write(pmc, AT91_PMC_USB,
		  pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_USBS);
}

static int at91sam9n12_clk_usb_is_enabled(struct clk_hw *hw)
{
	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;

	return !!(pmc_read(pmc, AT91_PMC_USB) & AT91_PMC_USBS);
}

static const struct clk_ops at91sam9n12_usb_ops = {
	.enable = at91sam9n12_clk_usb_enable,
	.disable = at91sam9n12_clk_usb_disable,
	.is_enabled = at91sam9n12_clk_usb_is_enabled,
	.recalc_rate = at91sam9x5_clk_usb_recalc_rate,
	.determine_rate = at91sam9x5_clk_usb_determine_rate,
	.set_rate = at91sam9x5_clk_usb_set_rate,
};

static struct clk * __init
at91sam9x5_clk_register_usb(struct at91_pmc *pmc, const char *name,
			    const char **parent_names, u8 num_parents)
{
	struct at91sam9x5_clk_usb *usb;
	struct clk *clk = NULL;
	struct clk_init_data init;

	usb = kzalloc(sizeof(*usb), GFP_KERNEL);
	if (!usb)
		return ERR_PTR(-ENOMEM);

	init.name = name;
	init.ops = &at91sam9x5_usb_ops;
	init.parent_names = parent_names;
	init.num_parents = num_parents;
	init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE |
		     CLK_SET_RATE_PARENT;

	usb->hw.init = &init;
	usb->pmc = pmc;

	clk = clk_register(NULL, &usb->hw);
	if (IS_ERR(clk))
		kfree(usb);

	return clk;
}

static struct clk * __init
at91sam9n12_clk_register_usb(struct at91_pmc *pmc, const char *name,
			     const char *parent_name)
{
	struct at91sam9x5_clk_usb *usb;
	struct clk *clk = NULL;
	struct clk_init_data init;

	usb = kzalloc(sizeof(*usb), GFP_KERNEL);
	if (!usb)
		return ERR_PTR(-ENOMEM);

	init.name = name;
	init.ops = &at91sam9n12_usb_ops;
	init.parent_names = &parent_name;
	init.num_parents = 1;
	init.flags = CLK_SET_RATE_GATE | CLK_SET_RATE_PARENT;

	usb->hw.init = &init;
	usb->pmc = pmc;

	clk = clk_register(NULL, &usb->hw);
	if (IS_ERR(clk))
		kfree(usb);

	return clk;
}

static unsigned long at91rm9200_clk_usb_recalc_rate(struct clk_hw *hw,
						    unsigned long parent_rate)
{
	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;
	u32 tmp;
	u8 usbdiv;

	tmp = pmc_read(pmc, AT91_CKGR_PLLBR);
	usbdiv = (tmp & AT91_PMC_USBDIV) >> RM9200_USB_DIV_SHIFT;
	if (usb->divisors[usbdiv])
		return parent_rate / usb->divisors[usbdiv];

	return 0;
}

static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate,
					  unsigned long *parent_rate)
{
	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
	struct clk *parent = __clk_get_parent(hw->clk);
	unsigned long bestrate = 0;
	int bestdiff = -1;
	unsigned long tmprate;
	int tmpdiff;
	int i = 0;

	for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
		unsigned long tmp_parent_rate;

		if (!usb->divisors[i])
			continue;

		tmp_parent_rate = rate * usb->divisors[i];
		tmp_parent_rate = __clk_round_rate(parent, tmp_parent_rate);
		tmprate = DIV_ROUND_CLOSEST(tmp_parent_rate, usb->divisors[i]);
		if (tmprate < rate)
			tmpdiff = rate - tmprate;
		else
			tmpdiff = tmprate - rate;

		if (bestdiff < 0 || bestdiff > tmpdiff) {
			bestrate = tmprate;
			bestdiff = tmpdiff;
			*parent_rate = tmp_parent_rate;
		}

		if (!bestdiff)
			break;
	}

	return bestrate;
}

static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate,
				       unsigned long parent_rate)
{
	u32 tmp;
	int i;
	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
	struct at91_pmc *pmc = usb->pmc;
	unsigned long div;

	if (!rate)
		return -EINVAL;

	div = DIV_ROUND_CLOSEST(parent_rate, rate);

	for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) {
		if (usb->divisors[i] == div) {
			tmp = pmc_read(pmc, AT91_CKGR_PLLBR) &
			      ~AT91_PMC_USBDIV;
			tmp |= i << RM9200_USB_DIV_SHIFT;
			pmc_write(pmc, AT91_CKGR_PLLBR, tmp);
			return 0;
		}
	}

	return -EINVAL;
}

static const struct clk_ops at91rm9200_usb_ops = {
	.recalc_rate = at91rm9200_clk_usb_recalc_rate,
	.round_rate = at91rm9200_clk_usb_round_rate,
	.set_rate = at91rm9200_clk_usb_set_rate,
};

static struct clk * __init
at91rm9200_clk_register_usb(struct at91_pmc *pmc, const char *name,
			    const char *parent_name, const u32 *divisors)
{
	struct at91rm9200_clk_usb *usb;
	struct clk *clk = NULL;
	struct clk_init_data init;

	usb = kzalloc(sizeof(*usb), GFP_KERNEL);
	if (!usb)
		return ERR_PTR(-ENOMEM);

	init.name = name;
	init.ops = &at91rm9200_usb_ops;
	init.parent_names = &parent_name;
	init.num_parents = 1;
	init.flags = CLK_SET_RATE_PARENT;

	usb->hw.init = &init;
	usb->pmc = pmc;
	memcpy(usb->divisors, divisors, sizeof(usb->divisors));

	clk = clk_register(NULL, &usb->hw);
	if (IS_ERR(clk))
		kfree(usb);

	return clk;
}

void __init of_at91sam9x5_clk_usb_setup(struct device_node *np,
					struct at91_pmc *pmc)
{
	struct clk *clk;
	int i;
	int num_parents;
	const char *parent_names[USB_SOURCE_MAX];
	const char *name = np->name;

	num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells");
	if (num_parents <= 0 || num_parents > USB_SOURCE_MAX)
		return;

	for (i = 0; i < num_parents; i++) {
		parent_names[i] = of_clk_get_parent_name(np, i);
		if (!parent_names[i])
			return;
	}

	of_property_read_string(np, "clock-output-names", &name);

	clk = at91sam9x5_clk_register_usb(pmc, name, parent_names, num_parents);
	if (IS_ERR(clk))
		return;

	of_clk_add_provider(np, of_clk_src_simple_get, clk);
}

void __init of_at91sam9n12_clk_usb_setup(struct device_node *np,
					 struct at91_pmc *pmc)
{
	struct clk *clk;
	const char *parent_name;
	const char *name = np->name;

	parent_name = of_clk_get_parent_name(np, 0);
	if (!parent_name)
		return;

	of_property_read_string(np, "clock-output-names", &name);

	clk = at91sam9n12_clk_register_usb(pmc, name, parent_name);
	if (IS_ERR(clk))
		return;

	of_clk_add_provider(np, of_clk_src_simple_get, clk);
}

void __init of_at91rm9200_clk_usb_setup(struct device_node *np,
					struct at91_pmc *pmc)
{
	struct clk *clk;
	const char *parent_name;
	const char *name = np->name;
	u32 divisors[4] = {0, 0, 0, 0};

	parent_name = of_clk_get_parent_name(np, 0);
	if (!parent_name)
		return;

	of_property_read_u32_array(np, "atmel,clk-divisors", divisors, 4);
	if (!divisors[0])
		return;

	of_property_read_string(np, "clock-output-names", &name);

	clk = at91rm9200_clk_register_usb(pmc, name, parent_name, divisors);
	if (IS_ERR(clk))
		return;

	of_clk_add_provider(np, of_clk_src_simple_get, clk);
}