summaryrefslogtreecommitdiffstats
path: root/drivers/clk/samsung/clk-exynos-clkout.c
blob: 6c6afb87b4ce3babf8d7625581a5f7a288b1a1d5 (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
/*
 * Copyright (c) 2014 Samsung Electronics Co., Ltd.
 * Author: Tomasz Figa <t.figa@samsung.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.
 *
 * Clock driver for Exynos clock output
 */

#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/syscore_ops.h>

#define EXYNOS_CLKOUT_NR_CLKS		1
#define EXYNOS_CLKOUT_PARENTS		32

#define EXYNOS_PMU_DEBUG_REG		0xa00
#define EXYNOS_CLKOUT_DISABLE_SHIFT	0
#define EXYNOS_CLKOUT_MUX_SHIFT		8
#define EXYNOS4_CLKOUT_MUX_MASK		0xf
#define EXYNOS5_CLKOUT_MUX_MASK		0x1f

struct exynos_clkout {
	struct clk_gate gate;
	struct clk_mux mux;
	spinlock_t slock;
	struct clk_onecell_data data;
	struct clk *clk_table[EXYNOS_CLKOUT_NR_CLKS];
	void __iomem *reg;
	u32 pmu_debug_save;
};

static struct exynos_clkout *clkout;

static int exynos_clkout_suspend(void)
{
	clkout->pmu_debug_save = readl(clkout->reg + EXYNOS_PMU_DEBUG_REG);

	return 0;
}

static void exynos_clkout_resume(void)
{
	writel(clkout->pmu_debug_save, clkout->reg + EXYNOS_PMU_DEBUG_REG);
}

static struct syscore_ops exynos_clkout_syscore_ops = {
	.suspend = exynos_clkout_suspend,
	.resume = exynos_clkout_resume,
};

static void __init exynos_clkout_init(struct device_node *node, u32 mux_mask)
{
	const char *parent_names[EXYNOS_CLKOUT_PARENTS];
	struct clk *parents[EXYNOS_CLKOUT_PARENTS];
	int parent_count;
	int ret;
	int i;

	clkout = kzalloc(sizeof(*clkout), GFP_KERNEL);
	if (!clkout)
		return;

	spin_lock_init(&clkout->slock);

	parent_count = 0;
	for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i) {
		char name[] = "clkoutXX";

		snprintf(name, sizeof(name), "clkout%d", i);
		parents[i] = of_clk_get_by_name(node, name);
		if (IS_ERR(parents[i])) {
			parent_names[i] = "none";
			continue;
		}

		parent_names[i] = __clk_get_name(parents[i]);
		parent_count = i + 1;
	}

	if (!parent_count)
		goto free_clkout;

	clkout->reg = of_iomap(node, 0);
	if (!clkout->reg)
		goto clks_put;

	clkout->gate.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG;
	clkout->gate.bit_idx = EXYNOS_CLKOUT_DISABLE_SHIFT;
	clkout->gate.flags = CLK_GATE_SET_TO_DISABLE;
	clkout->gate.lock = &clkout->slock;

	clkout->mux.reg = clkout->reg + EXYNOS_PMU_DEBUG_REG;
	clkout->mux.mask = mux_mask;
	clkout->mux.shift = EXYNOS_CLKOUT_MUX_SHIFT;
	clkout->mux.lock = &clkout->slock;

	clkout->clk_table[0] = clk_register_composite(NULL, "clkout",
				parent_names, parent_count, &clkout->mux.hw,
				&clk_mux_ops, NULL, NULL, &clkout->gate.hw,
				&clk_gate_ops, CLK_SET_RATE_PARENT
				| CLK_SET_RATE_NO_REPARENT);
	if (IS_ERR(clkout->clk_table[0]))
		goto err_unmap;

	clkout->data.clks = clkout->clk_table;
	clkout->data.clk_num = EXYNOS_CLKOUT_NR_CLKS;
	ret = of_clk_add_provider(node, of_clk_src_onecell_get, &clkout->data);
	if (ret)
		goto err_clk_unreg;

	register_syscore_ops(&exynos_clkout_syscore_ops);

	return;

err_clk_unreg:
	clk_unregister(clkout->clk_table[0]);
err_unmap:
	iounmap(clkout->reg);
clks_put:
	for (i = 0; i < EXYNOS_CLKOUT_PARENTS; ++i)
		if (!IS_ERR(parents[i]))
			clk_put(parents[i]);
free_clkout:
	kfree(clkout);

	pr_err("%s: failed to register clkout clock\n", __func__);
}

/*
 * We use CLK_OF_DECLARE_DRIVER initialization method to avoid setting
 * the OF_POPULATED flag on the pmu device tree node, so later the
 * Exynos PMU platform device can be properly probed with PMU driver.
 */

static void __init exynos4_clkout_init(struct device_node *node)
{
	exynos_clkout_init(node, EXYNOS4_CLKOUT_MUX_MASK);
}
CLK_OF_DECLARE_DRIVER(exynos4210_clkout, "samsung,exynos4210-pmu",
		exynos4_clkout_init);
CLK_OF_DECLARE_DRIVER(exynos4212_clkout, "samsung,exynos4212-pmu",
		exynos4_clkout_init);
CLK_OF_DECLARE_DRIVER(exynos4412_clkout, "samsung,exynos4412-pmu",
		exynos4_clkout_init);
CLK_OF_DECLARE_DRIVER(exynos3250_clkout, "samsung,exynos3250-pmu",
		exynos4_clkout_init);

static void __init exynos5_clkout_init(struct device_node *node)
{
	exynos_clkout_init(node, EXYNOS5_CLKOUT_MUX_MASK);
}
CLK_OF_DECLARE_DRIVER(exynos5250_clkout, "samsung,exynos5250-pmu",
		exynos5_clkout_init);
CLK_OF_DECLARE_DRIVER(exynos5410_clkout, "samsung,exynos5410-pmu",
		exynos5_clkout_init);
CLK_OF_DECLARE_DRIVER(exynos5420_clkout, "samsung,exynos5420-pmu",
		exynos5_clkout_init);
CLK_OF_DECLARE_DRIVER(exynos5433_clkout, "samsung,exynos5433-pmu",
		exynos5_clkout_init);