summaryrefslogtreecommitdiffstats
path: root/drivers/clk/ux500/clk-sysctrl.c
blob: 8a4e93ce1e42cad595e8d8fa439e77f1ad67a2e0 (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
/*
 * Sysctrl clock implementation for ux500 platform.
 *
 * Copyright (C) 2013 ST-Ericsson SA
 * Author: Ulf Hansson <ulf.hansson@linaro.org>
 *
 * License terms: GNU General Public License (GPL) version 2
 */

#include <linux/clk-provider.h>
#include <linux/mfd/abx500/ab8500-sysctrl.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/err.h>
#include "clk.h"

#define SYSCTRL_MAX_NUM_PARENTS 4

#define to_clk_sysctrl(_hw) container_of(_hw, struct clk_sysctrl, hw)

struct clk_sysctrl {
	struct clk_hw hw;
	struct device *dev;
	u8 parent_index;
	u16 reg_sel[SYSCTRL_MAX_NUM_PARENTS];
	u8 reg_mask[SYSCTRL_MAX_NUM_PARENTS];
	u8 reg_bits[SYSCTRL_MAX_NUM_PARENTS];
	unsigned long rate;
	unsigned long enable_delay_us;
};

/* Sysctrl clock operations. */

static int clk_sysctrl_prepare(struct clk_hw *hw)
{
	int ret;
	struct clk_sysctrl *clk = to_clk_sysctrl(hw);

	ret = ab8500_sysctrl_write(clk->reg_sel[0], clk->reg_mask[0],
				clk->reg_bits[0]);

	if (!ret && clk->enable_delay_us)
		usleep_range(clk->enable_delay_us, clk->enable_delay_us);

	return ret;
}

static void clk_sysctrl_unprepare(struct clk_hw *hw)
{
	struct clk_sysctrl *clk = to_clk_sysctrl(hw);
	if (ab8500_sysctrl_clear(clk->reg_sel[0], clk->reg_mask[0]))
		dev_err(clk->dev, "clk_sysctrl: %s fail to clear %s.\n",
			__func__, clk_hw_get_name(hw));
}

static unsigned long clk_sysctrl_recalc_rate(struct clk_hw *hw,
					unsigned long parent_rate)
{
	struct clk_sysctrl *clk = to_clk_sysctrl(hw);
	return clk->rate;
}

static int clk_sysctrl_set_parent(struct clk_hw *hw, u8 index)
{
	struct clk_sysctrl *clk = to_clk_sysctrl(hw);
	u8 old_index = clk->parent_index;
	int ret = 0;

	if (clk->reg_sel[old_index]) {
		ret = ab8500_sysctrl_clear(clk->reg_sel[old_index],
					clk->reg_mask[old_index]);
		if (ret)
			return ret;
	}

	if (clk->reg_sel[index]) {
		ret = ab8500_sysctrl_write(clk->reg_sel[index],
					clk->reg_mask[index],
					clk->reg_bits[index]);
		if (ret) {
			if (clk->reg_sel[old_index])
				ab8500_sysctrl_write(clk->reg_sel[old_index],
						clk->reg_mask[old_index],
						clk->reg_bits[old_index]);
			return ret;
		}
	}
	clk->parent_index = index;

	return ret;
}

static u8 clk_sysctrl_get_parent(struct clk_hw *hw)
{
	struct clk_sysctrl *clk = to_clk_sysctrl(hw);
	return clk->parent_index;
}

static const struct clk_ops clk_sysctrl_gate_ops = {
	.prepare = clk_sysctrl_prepare,
	.unprepare = clk_sysctrl_unprepare,
};

static const struct clk_ops clk_sysctrl_gate_fixed_rate_ops = {
	.prepare = clk_sysctrl_prepare,
	.unprepare = clk_sysctrl_unprepare,
	.recalc_rate = clk_sysctrl_recalc_rate,
};

static const struct clk_ops clk_sysctrl_set_parent_ops = {
	.set_parent = clk_sysctrl_set_parent,
	.get_parent = clk_sysctrl_get_parent,
};

static struct clk *clk_reg_sysctrl(struct device *dev,
				const char *name,
				const char **parent_names,
				u8 num_parents,
				u16 *reg_sel,
				u8 *reg_mask,
				u8 *reg_bits,
				unsigned long rate,
				unsigned long enable_delay_us,
				unsigned long flags,
				const struct clk_ops *clk_sysctrl_ops)
{
	struct clk_sysctrl *clk;
	struct clk_init_data clk_sysctrl_init;
	struct clk *clk_reg;
	int i;

	if (!dev)
		return ERR_PTR(-EINVAL);

	if (!name || (num_parents > SYSCTRL_MAX_NUM_PARENTS)) {
		dev_err(dev, "clk_sysctrl: invalid arguments passed\n");
		return ERR_PTR(-EINVAL);
	}

	clk = devm_kzalloc(dev, sizeof(struct clk_sysctrl), GFP_KERNEL);
	if (!clk) {
		dev_err(dev, "clk_sysctrl: could not allocate clk\n");
		return ERR_PTR(-ENOMEM);
	}

	/* set main clock registers */
	clk->reg_sel[0] = reg_sel[0];
	clk->reg_bits[0] = reg_bits[0];
	clk->reg_mask[0] = reg_mask[0];

	/* handle clocks with more than one parent */
	for (i = 1; i < num_parents; i++) {
		clk->reg_sel[i] = reg_sel[i];
		clk->reg_bits[i] = reg_bits[i];
		clk->reg_mask[i] = reg_mask[i];
	}

	clk->parent_index = 0;
	clk->rate = rate;
	clk->enable_delay_us = enable_delay_us;
	clk->dev = dev;

	clk_sysctrl_init.name = name;
	clk_sysctrl_init.ops = clk_sysctrl_ops;
	clk_sysctrl_init.flags = flags;
	clk_sysctrl_init.parent_names = parent_names;
	clk_sysctrl_init.num_parents = num_parents;
	clk->hw.init = &clk_sysctrl_init;

	clk_reg = devm_clk_register(clk->dev, &clk->hw);
	if (IS_ERR(clk_reg))
		dev_err(dev, "clk_sysctrl: clk_register failed\n");

	return clk_reg;
}

struct clk *clk_reg_sysctrl_gate(struct device *dev,
				const char *name,
				const char *parent_name,
				u16 reg_sel,
				u8 reg_mask,
				u8 reg_bits,
				unsigned long enable_delay_us,
				unsigned long flags)
{
	const char **parent_names = (parent_name ? &parent_name : NULL);
	u8 num_parents = (parent_name ? 1 : 0);

	return clk_reg_sysctrl(dev, name, parent_names, num_parents,
			&reg_sel, &reg_mask, &reg_bits, 0, enable_delay_us,
			flags, &clk_sysctrl_gate_ops);
}

struct clk *clk_reg_sysctrl_gate_fixed_rate(struct device *dev,
					const char *name,
					const char *parent_name,
					u16 reg_sel,
					u8 reg_mask,
					u8 reg_bits,
					unsigned long rate,
					unsigned long enable_delay_us,
					unsigned long flags)
{
	const char **parent_names = (parent_name ? &parent_name : NULL);
	u8 num_parents = (parent_name ? 1 : 0);

	return clk_reg_sysctrl(dev, name, parent_names, num_parents,
			&reg_sel, &reg_mask, &reg_bits,
			rate, enable_delay_us, flags,
			&clk_sysctrl_gate_fixed_rate_ops);
}

struct clk *clk_reg_sysctrl_set_parent(struct device *dev,
				const char *name,
				const char **parent_names,
				u8 num_parents,
				u16 *reg_sel,
				u8 *reg_mask,
				u8 *reg_bits,
				unsigned long flags)
{
	return clk_reg_sysctrl(dev, name, parent_names, num_parents,
			reg_sel, reg_mask, reg_bits, 0, 0, flags,
			&clk_sysctrl_set_parent_ops);
}