summaryrefslogtreecommitdiff
path: root/drivers/clk/clk-palmas.c
blob: 5efb10776ae5fcaaaa8ffc0ef86cc1bf23515ef9 (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
// SPDX-License-Identifier: GPL-2.0
/*
 * Clock driver for Palmas device.
 *
 * Copyright (c) 2013, NVIDIA Corporation.
 * Copyright (c) 2013-2014 Texas Instruments, Inc.
 *
 * Author:	Laxman Dewangan <ldewangan@nvidia.com>
 *		Peter Ujfalusi <peter.ujfalusi@ti.com>
 */

#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/mfd/palmas.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#define PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE1	1
#define PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE2	2
#define PALMAS_CLOCK_DT_EXT_CONTROL_NSLEEP	3

struct palmas_clk32k_desc {
	const char *clk_name;
	unsigned int control_reg;
	unsigned int enable_mask;
	unsigned int sleep_mask;
	unsigned int sleep_reqstr_id;
	int delay;
};

struct palmas_clock_info {
	struct device *dev;
	struct clk_hw hw;
	struct palmas *palmas;
	const struct palmas_clk32k_desc *clk_desc;
	int ext_control_pin;
};

static inline struct palmas_clock_info *to_palmas_clks_info(struct clk_hw *hw)
{
	return container_of(hw, struct palmas_clock_info, hw);
}

static unsigned long palmas_clks_recalc_rate(struct clk_hw *hw,
					     unsigned long parent_rate)
{
	return 32768;
}

static int palmas_clks_prepare(struct clk_hw *hw)
{
	struct palmas_clock_info *cinfo = to_palmas_clks_info(hw);
	int ret;

	ret = palmas_update_bits(cinfo->palmas, PALMAS_RESOURCE_BASE,
				 cinfo->clk_desc->control_reg,
				 cinfo->clk_desc->enable_mask,
				 cinfo->clk_desc->enable_mask);
	if (ret < 0)
		dev_err(cinfo->dev, "Reg 0x%02x update failed, %d\n",
			cinfo->clk_desc->control_reg, ret);
	else if (cinfo->clk_desc->delay)
		udelay(cinfo->clk_desc->delay);

	return ret;
}

static void palmas_clks_unprepare(struct clk_hw *hw)
{
	struct palmas_clock_info *cinfo = to_palmas_clks_info(hw);
	int ret;

	/*
	 * Clock can be disabled through external pin if it is externally
	 * controlled.
	 */
	if (cinfo->ext_control_pin)
		return;

	ret = palmas_update_bits(cinfo->palmas, PALMAS_RESOURCE_BASE,
				 cinfo->clk_desc->control_reg,
				 cinfo->clk_desc->enable_mask, 0);
	if (ret < 0)
		dev_err(cinfo->dev, "Reg 0x%02x update failed, %d\n",
			cinfo->clk_desc->control_reg, ret);
}

static int palmas_clks_is_prepared(struct clk_hw *hw)
{
	struct palmas_clock_info *cinfo = to_palmas_clks_info(hw);
	int ret;
	u32 val;

	if (cinfo->ext_control_pin)
		return 1;

	ret = palmas_read(cinfo->palmas, PALMAS_RESOURCE_BASE,
			  cinfo->clk_desc->control_reg, &val);
	if (ret < 0) {
		dev_err(cinfo->dev, "Reg 0x%02x read failed, %d\n",
			cinfo->clk_desc->control_reg, ret);
		return ret;
	}
	return !!(val & cinfo->clk_desc->enable_mask);
}

static const struct clk_ops palmas_clks_ops = {
	.prepare	= palmas_clks_prepare,
	.unprepare	= palmas_clks_unprepare,
	.is_prepared	= palmas_clks_is_prepared,
	.recalc_rate	= palmas_clks_recalc_rate,
};

struct palmas_clks_of_match_data {
	struct clk_init_data init;
	const struct palmas_clk32k_desc desc;
};

static const struct palmas_clks_of_match_data palmas_of_clk32kg = {
	.init = {
		.name = "clk32kg",
		.ops = &palmas_clks_ops,
		.flags = CLK_IGNORE_UNUSED,
	},
	.desc = {
		.clk_name = "clk32kg",
		.control_reg = PALMAS_CLK32KG_CTRL,
		.enable_mask = PALMAS_CLK32KG_CTRL_MODE_ACTIVE,
		.sleep_mask = PALMAS_CLK32KG_CTRL_MODE_SLEEP,
		.sleep_reqstr_id = PALMAS_EXTERNAL_REQSTR_ID_CLK32KG,
		.delay = 200,
	},
};

static const struct palmas_clks_of_match_data palmas_of_clk32kgaudio = {
	.init = {
		.name = "clk32kgaudio",
		.ops = &palmas_clks_ops,
		.flags = CLK_IGNORE_UNUSED,
	},
	.desc = {
		.clk_name = "clk32kgaudio",
		.control_reg = PALMAS_CLK32KGAUDIO_CTRL,
		.enable_mask = PALMAS_CLK32KG_CTRL_MODE_ACTIVE,
		.sleep_mask = PALMAS_CLK32KG_CTRL_MODE_SLEEP,
		.sleep_reqstr_id = PALMAS_EXTERNAL_REQSTR_ID_CLK32KGAUDIO,
		.delay = 200,
	},
};

static const struct of_device_id palmas_clks_of_match[] = {
	{
		.compatible = "ti,palmas-clk32kg",
		.data = &palmas_of_clk32kg,
	},
	{
		.compatible = "ti,palmas-clk32kgaudio",
		.data = &palmas_of_clk32kgaudio,
	},
	{ },
};
MODULE_DEVICE_TABLE(of, palmas_clks_of_match);

static void palmas_clks_get_clk_data(struct platform_device *pdev,
				     struct palmas_clock_info *cinfo)
{
	struct device_node *node = pdev->dev.of_node;
	unsigned int prop;
	int ret;

	ret = of_property_read_u32(node, "ti,external-sleep-control",
				   &prop);
	if (ret)
		return;

	switch (prop) {
	case PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE1:
		prop = PALMAS_EXT_CONTROL_ENABLE1;
		break;
	case PALMAS_CLOCK_DT_EXT_CONTROL_ENABLE2:
		prop = PALMAS_EXT_CONTROL_ENABLE2;
		break;
	case PALMAS_CLOCK_DT_EXT_CONTROL_NSLEEP:
		prop = PALMAS_EXT_CONTROL_NSLEEP;
		break;
	default:
		dev_warn(&pdev->dev, "%pOFn: Invalid ext control option: %u\n",
			 node, prop);
		prop = 0;
		break;
	}
	cinfo->ext_control_pin = prop;
}

static int palmas_clks_init_configure(struct palmas_clock_info *cinfo)
{
	int ret;

	ret = palmas_update_bits(cinfo->palmas, PALMAS_RESOURCE_BASE,
				 cinfo->clk_desc->control_reg,
				 cinfo->clk_desc->sleep_mask, 0);
	if (ret < 0) {
		dev_err(cinfo->dev, "Reg 0x%02x update failed, %d\n",
			cinfo->clk_desc->control_reg, ret);
		return ret;
	}

	if (cinfo->ext_control_pin) {
		ret = clk_prepare(cinfo->hw.clk);
		if (ret < 0) {
			dev_err(cinfo->dev, "Clock prep failed, %d\n", ret);
			return ret;
		}

		ret = palmas_ext_control_req_config(cinfo->palmas,
					cinfo->clk_desc->sleep_reqstr_id,
					cinfo->ext_control_pin, true);
		if (ret < 0) {
			dev_err(cinfo->dev, "Ext config for %s failed, %d\n",
				cinfo->clk_desc->clk_name, ret);
			clk_unprepare(cinfo->hw.clk);
			return ret;
		}
	}

	return ret;
}
static int palmas_clks_probe(struct platform_device *pdev)
{
	struct palmas *palmas = dev_get_drvdata(pdev->dev.parent);
	struct device_node *node = pdev->dev.of_node;
	const struct palmas_clks_of_match_data *match_data;
	struct palmas_clock_info *cinfo;
	int ret;

	match_data = of_device_get_match_data(&pdev->dev);
	if (!match_data)
		return 1;

	cinfo = devm_kzalloc(&pdev->dev, sizeof(*cinfo), GFP_KERNEL);
	if (!cinfo)
		return -ENOMEM;

	palmas_clks_get_clk_data(pdev, cinfo);
	platform_set_drvdata(pdev, cinfo);

	cinfo->dev = &pdev->dev;
	cinfo->palmas = palmas;

	cinfo->clk_desc = &match_data->desc;
	cinfo->hw.init = &match_data->init;
	ret = devm_clk_hw_register(&pdev->dev, &cinfo->hw);
	if (ret) {
		dev_err(&pdev->dev, "Fail to register clock %s, %d\n",
			match_data->desc.clk_name, ret);
		return ret;
	}

	ret = palmas_clks_init_configure(cinfo);
	if (ret < 0) {
		dev_err(&pdev->dev, "Clock config failed, %d\n", ret);
		return ret;
	}

	ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get, &cinfo->hw);
	if (ret < 0)
		dev_err(&pdev->dev, "Fail to add clock driver, %d\n", ret);
	return ret;
}

static void palmas_clks_remove(struct platform_device *pdev)
{
	of_clk_del_provider(pdev->dev.of_node);
}

static struct platform_driver palmas_clks_driver = {
	.driver = {
		.name = "palmas-clk",
		.of_match_table = palmas_clks_of_match,
	},
	.probe = palmas_clks_probe,
	.remove_new = palmas_clks_remove,
};

module_platform_driver(palmas_clks_driver);

MODULE_DESCRIPTION("Clock driver for Palmas Series Devices");
MODULE_ALIAS("platform:palmas-clk");
MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
MODULE_LICENSE("GPL v2");