1/*
2 * clk-s2mps11.c - Clock driver for S2MPS11.
3 *
4 * Copyright (C) 2013,2014 Samsung Electornics
5 *
6 * This program is free software; you can redistribute  it and/or modify it
7 * under  the terms of  the GNU General  Public License as published by the
8 * Free Software Foundation;  either version 2 of the  License, or (at your
9 * option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 * GNU General Public License for more details.
15 *
16 */
17
18#include <linux/module.h>
19#include <linux/err.h>
20#include <linux/of.h>
21#include <linux/clkdev.h>
22#include <linux/regmap.h>
23#include <linux/clk-provider.h>
24#include <linux/platform_device.h>
25#include <linux/mfd/samsung/s2mps11.h>
26#include <linux/mfd/samsung/s2mps13.h>
27#include <linux/mfd/samsung/s2mps14.h>
28#include <linux/mfd/samsung/s5m8767.h>
29#include <linux/mfd/samsung/core.h>
30
31#define s2mps11_name(a) (a->hw.init->name)
32
33static struct clk **clk_table;
34static struct clk_onecell_data clk_data;
35
36enum {
37	S2MPS11_CLK_AP = 0,
38	S2MPS11_CLK_CP,
39	S2MPS11_CLK_BT,
40	S2MPS11_CLKS_NUM,
41};
42
43struct s2mps11_clk {
44	struct sec_pmic_dev *iodev;
45	struct device_node *clk_np;
46	struct clk_hw hw;
47	struct clk *clk;
48	struct clk_lookup *lookup;
49	u32 mask;
50	unsigned int reg;
51};
52
53static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
54{
55	return container_of(hw, struct s2mps11_clk, hw);
56}
57
58static int s2mps11_clk_prepare(struct clk_hw *hw)
59{
60	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
61
62	return regmap_update_bits(s2mps11->iodev->regmap_pmic,
63				 s2mps11->reg,
64				 s2mps11->mask, s2mps11->mask);
65}
66
67static void s2mps11_clk_unprepare(struct clk_hw *hw)
68{
69	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
70
71	regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
72			   s2mps11->mask, ~s2mps11->mask);
73}
74
75static int s2mps11_clk_is_prepared(struct clk_hw *hw)
76{
77	int ret;
78	u32 val;
79	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
80
81	ret = regmap_read(s2mps11->iodev->regmap_pmic,
82				s2mps11->reg, &val);
83	if (ret < 0)
84		return -EINVAL;
85
86	return val & s2mps11->mask;
87}
88
89static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
90					     unsigned long parent_rate)
91{
92	return 32768;
93}
94
95static struct clk_ops s2mps11_clk_ops = {
96	.prepare	= s2mps11_clk_prepare,
97	.unprepare	= s2mps11_clk_unprepare,
98	.is_prepared	= s2mps11_clk_is_prepared,
99	.recalc_rate	= s2mps11_clk_recalc_rate,
100};
101
102static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
103	[S2MPS11_CLK_AP] = {
104		.name = "s2mps11_ap",
105		.ops = &s2mps11_clk_ops,
106		.flags = CLK_IS_ROOT,
107	},
108	[S2MPS11_CLK_CP] = {
109		.name = "s2mps11_cp",
110		.ops = &s2mps11_clk_ops,
111		.flags = CLK_IS_ROOT,
112	},
113	[S2MPS11_CLK_BT] = {
114		.name = "s2mps11_bt",
115		.ops = &s2mps11_clk_ops,
116		.flags = CLK_IS_ROOT,
117	},
118};
119
120static struct clk_init_data s2mps13_clks_init[S2MPS11_CLKS_NUM] = {
121	[S2MPS11_CLK_AP] = {
122		.name = "s2mps13_ap",
123		.ops = &s2mps11_clk_ops,
124		.flags = CLK_IS_ROOT,
125	},
126	[S2MPS11_CLK_CP] = {
127		.name = "s2mps13_cp",
128		.ops = &s2mps11_clk_ops,
129		.flags = CLK_IS_ROOT,
130	},
131	[S2MPS11_CLK_BT] = {
132		.name = "s2mps13_bt",
133		.ops = &s2mps11_clk_ops,
134		.flags = CLK_IS_ROOT,
135	},
136};
137
138static struct clk_init_data s2mps14_clks_init[S2MPS11_CLKS_NUM] = {
139	[S2MPS11_CLK_AP] = {
140		.name = "s2mps14_ap",
141		.ops = &s2mps11_clk_ops,
142		.flags = CLK_IS_ROOT,
143	},
144	[S2MPS11_CLK_BT] = {
145		.name = "s2mps14_bt",
146		.ops = &s2mps11_clk_ops,
147		.flags = CLK_IS_ROOT,
148	},
149};
150
151static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
152		struct clk_init_data *clks_init)
153{
154	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
155	struct device_node *clk_np;
156	int i;
157
158	if (!iodev->dev->of_node)
159		return ERR_PTR(-EINVAL);
160
161	clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
162	if (!clk_np) {
163		dev_err(&pdev->dev, "could not find clock sub-node\n");
164		return ERR_PTR(-EINVAL);
165	}
166
167	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
168		if (!clks_init[i].name)
169			continue; /* Skip clocks not present in some devices */
170		of_property_read_string_index(clk_np, "clock-output-names", i,
171				&clks_init[i].name);
172	}
173
174	return clk_np;
175}
176
177static int s2mps11_clk_probe(struct platform_device *pdev)
178{
179	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
180	struct s2mps11_clk *s2mps11_clks, *s2mps11_clk;
181	unsigned int s2mps11_reg;
182	struct clk_init_data *clks_init;
183	int i, ret = 0;
184
185	s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
186				sizeof(*s2mps11_clk), GFP_KERNEL);
187	if (!s2mps11_clks)
188		return -ENOMEM;
189
190	s2mps11_clk = s2mps11_clks;
191
192	clk_table = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
193				sizeof(struct clk *), GFP_KERNEL);
194	if (!clk_table)
195		return -ENOMEM;
196
197	switch(platform_get_device_id(pdev)->driver_data) {
198	case S2MPS11X:
199		s2mps11_reg = S2MPS11_REG_RTC_CTRL;
200		clks_init = s2mps11_clks_init;
201		break;
202	case S2MPS13X:
203		s2mps11_reg = S2MPS13_REG_RTCCTRL;
204		clks_init = s2mps13_clks_init;
205		break;
206	case S2MPS14X:
207		s2mps11_reg = S2MPS14_REG_RTCCTRL;
208		clks_init = s2mps14_clks_init;
209		break;
210	case S5M8767X:
211		s2mps11_reg = S5M8767_REG_CTRL1;
212		clks_init = s2mps11_clks_init;
213		break;
214	default:
215		dev_err(&pdev->dev, "Invalid device type\n");
216		return -EINVAL;
217	}
218
219	/* Store clocks of_node in first element of s2mps11_clks array */
220	s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, clks_init);
221	if (IS_ERR(s2mps11_clks->clk_np))
222		return PTR_ERR(s2mps11_clks->clk_np);
223
224	for (i = 0; i < S2MPS11_CLKS_NUM; i++, s2mps11_clk++) {
225		if (!clks_init[i].name)
226			continue; /* Skip clocks not present in some devices */
227		s2mps11_clk->iodev = iodev;
228		s2mps11_clk->hw.init = &clks_init[i];
229		s2mps11_clk->mask = 1 << i;
230		s2mps11_clk->reg = s2mps11_reg;
231
232		s2mps11_clk->clk = devm_clk_register(&pdev->dev,
233							&s2mps11_clk->hw);
234		if (IS_ERR(s2mps11_clk->clk)) {
235			dev_err(&pdev->dev, "Fail to register : %s\n",
236						s2mps11_name(s2mps11_clk));
237			ret = PTR_ERR(s2mps11_clk->clk);
238			goto err_reg;
239		}
240
241		s2mps11_clk->lookup = clkdev_create(s2mps11_clk->clk,
242					s2mps11_name(s2mps11_clk), NULL);
243		if (!s2mps11_clk->lookup) {
244			ret = -ENOMEM;
245			goto err_reg;
246		}
247	}
248
249	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
250		/* Skip clocks not present on S2MPS14 */
251		if (!clks_init[i].name)
252			continue;
253		clk_table[i] = s2mps11_clks[i].clk;
254	}
255
256	clk_data.clks = clk_table;
257	clk_data.clk_num = S2MPS11_CLKS_NUM;
258	of_clk_add_provider(s2mps11_clks->clk_np, of_clk_src_onecell_get,
259			&clk_data);
260
261	platform_set_drvdata(pdev, s2mps11_clks);
262
263	return ret;
264
265err_reg:
266	while (--i >= 0)
267		clkdev_drop(s2mps11_clks[i].lookup);
268
269	return ret;
270}
271
272static int s2mps11_clk_remove(struct platform_device *pdev)
273{
274	struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
275	int i;
276
277	of_clk_del_provider(s2mps11_clks[0].clk_np);
278	/* Drop the reference obtained in s2mps11_clk_parse_dt */
279	of_node_put(s2mps11_clks[0].clk_np);
280
281	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
282		/* Skip clocks not present on S2MPS14 */
283		if (!s2mps11_clks[i].lookup)
284			continue;
285		clkdev_drop(s2mps11_clks[i].lookup);
286	}
287
288	return 0;
289}
290
291static const struct platform_device_id s2mps11_clk_id[] = {
292	{ "s2mps11-clk", S2MPS11X},
293	{ "s2mps13-clk", S2MPS13X},
294	{ "s2mps14-clk", S2MPS14X},
295	{ "s5m8767-clk", S5M8767X},
296	{ },
297};
298MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
299
300static struct platform_driver s2mps11_clk_driver = {
301	.driver = {
302		.name  = "s2mps11-clk",
303	},
304	.probe = s2mps11_clk_probe,
305	.remove = s2mps11_clk_remove,
306	.id_table = s2mps11_clk_id,
307};
308
309static int __init s2mps11_clk_init(void)
310{
311	return platform_driver_register(&s2mps11_clk_driver);
312}
313subsys_initcall(s2mps11_clk_init);
314
315static void __exit s2mps11_clk_cleanup(void)
316{
317	platform_driver_unregister(&s2mps11_clk_driver);
318}
319module_exit(s2mps11_clk_cleanup);
320
321MODULE_DESCRIPTION("S2MPS11 Clock Driver");
322MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
323MODULE_LICENSE("GPL");
324