xref: /openbmc/linux/drivers/clk/clk-s2mps11.c (revision 4f3db074)
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 
33 static struct clk **clk_table;
34 static struct clk_onecell_data clk_data;
35 
36 enum {
37 	S2MPS11_CLK_AP = 0,
38 	S2MPS11_CLK_CP,
39 	S2MPS11_CLK_BT,
40 	S2MPS11_CLKS_NUM,
41 };
42 
43 struct 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 
53 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
54 {
55 	return container_of(hw, struct s2mps11_clk, hw);
56 }
57 
58 static int s2mps11_clk_prepare(struct clk_hw *hw)
59 {
60 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
61 	int ret;
62 
63 	ret = regmap_update_bits(s2mps11->iodev->regmap_pmic,
64 				 s2mps11->reg,
65 				 s2mps11->mask, s2mps11->mask);
66 
67 	return ret;
68 }
69 
70 static void s2mps11_clk_unprepare(struct clk_hw *hw)
71 {
72 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
73 	int ret;
74 
75 	ret = regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
76 			   s2mps11->mask, ~s2mps11->mask);
77 }
78 
79 static int s2mps11_clk_is_prepared(struct clk_hw *hw)
80 {
81 	int ret;
82 	u32 val;
83 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
84 
85 	ret = regmap_read(s2mps11->iodev->regmap_pmic,
86 				s2mps11->reg, &val);
87 	if (ret < 0)
88 		return -EINVAL;
89 
90 	return val & s2mps11->mask;
91 }
92 
93 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
94 					     unsigned long parent_rate)
95 {
96 	return 32768;
97 }
98 
99 static struct clk_ops s2mps11_clk_ops = {
100 	.prepare	= s2mps11_clk_prepare,
101 	.unprepare	= s2mps11_clk_unprepare,
102 	.is_prepared	= s2mps11_clk_is_prepared,
103 	.recalc_rate	= s2mps11_clk_recalc_rate,
104 };
105 
106 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
107 	[S2MPS11_CLK_AP] = {
108 		.name = "s2mps11_ap",
109 		.ops = &s2mps11_clk_ops,
110 		.flags = CLK_IS_ROOT,
111 	},
112 	[S2MPS11_CLK_CP] = {
113 		.name = "s2mps11_cp",
114 		.ops = &s2mps11_clk_ops,
115 		.flags = CLK_IS_ROOT,
116 	},
117 	[S2MPS11_CLK_BT] = {
118 		.name = "s2mps11_bt",
119 		.ops = &s2mps11_clk_ops,
120 		.flags = CLK_IS_ROOT,
121 	},
122 };
123 
124 static struct clk_init_data s2mps13_clks_init[S2MPS11_CLKS_NUM] = {
125 	[S2MPS11_CLK_AP] = {
126 		.name = "s2mps13_ap",
127 		.ops = &s2mps11_clk_ops,
128 		.flags = CLK_IS_ROOT,
129 	},
130 	[S2MPS11_CLK_CP] = {
131 		.name = "s2mps13_cp",
132 		.ops = &s2mps11_clk_ops,
133 		.flags = CLK_IS_ROOT,
134 	},
135 	[S2MPS11_CLK_BT] = {
136 		.name = "s2mps13_bt",
137 		.ops = &s2mps11_clk_ops,
138 		.flags = CLK_IS_ROOT,
139 	},
140 };
141 
142 static struct clk_init_data s2mps14_clks_init[S2MPS11_CLKS_NUM] = {
143 	[S2MPS11_CLK_AP] = {
144 		.name = "s2mps14_ap",
145 		.ops = &s2mps11_clk_ops,
146 		.flags = CLK_IS_ROOT,
147 	},
148 	[S2MPS11_CLK_BT] = {
149 		.name = "s2mps14_bt",
150 		.ops = &s2mps11_clk_ops,
151 		.flags = CLK_IS_ROOT,
152 	},
153 };
154 
155 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
156 		struct clk_init_data *clks_init)
157 {
158 	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
159 	struct device_node *clk_np;
160 	int i;
161 
162 	if (!iodev->dev->of_node)
163 		return ERR_PTR(-EINVAL);
164 
165 	clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
166 	if (!clk_np) {
167 		dev_err(&pdev->dev, "could not find clock sub-node\n");
168 		return ERR_PTR(-EINVAL);
169 	}
170 
171 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
172 		if (!clks_init[i].name)
173 			continue; /* Skip clocks not present in some devices */
174 		of_property_read_string_index(clk_np, "clock-output-names", i,
175 				&clks_init[i].name);
176 	}
177 
178 	return clk_np;
179 }
180 
181 static int s2mps11_clk_probe(struct platform_device *pdev)
182 {
183 	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
184 	struct s2mps11_clk *s2mps11_clks, *s2mps11_clk;
185 	unsigned int s2mps11_reg;
186 	struct clk_init_data *clks_init;
187 	int i, ret = 0;
188 
189 	s2mps11_clks = devm_kzalloc(&pdev->dev, sizeof(*s2mps11_clk) *
190 					S2MPS11_CLKS_NUM, GFP_KERNEL);
191 	if (!s2mps11_clks)
192 		return -ENOMEM;
193 
194 	s2mps11_clk = s2mps11_clks;
195 
196 	clk_table = devm_kzalloc(&pdev->dev, sizeof(struct clk *) *
197 				 S2MPS11_CLKS_NUM, GFP_KERNEL);
198 	if (!clk_table)
199 		return -ENOMEM;
200 
201 	switch(platform_get_device_id(pdev)->driver_data) {
202 	case S2MPS11X:
203 		s2mps11_reg = S2MPS11_REG_RTC_CTRL;
204 		clks_init = s2mps11_clks_init;
205 		break;
206 	case S2MPS13X:
207 		s2mps11_reg = S2MPS13_REG_RTCCTRL;
208 		clks_init = s2mps13_clks_init;
209 		break;
210 	case S2MPS14X:
211 		s2mps11_reg = S2MPS14_REG_RTCCTRL;
212 		clks_init = s2mps14_clks_init;
213 		break;
214 	case S5M8767X:
215 		s2mps11_reg = S5M8767_REG_CTRL1;
216 		clks_init = s2mps11_clks_init;
217 		break;
218 	default:
219 		dev_err(&pdev->dev, "Invalid device type\n");
220 		return -EINVAL;
221 	}
222 
223 	/* Store clocks of_node in first element of s2mps11_clks array */
224 	s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, clks_init);
225 	if (IS_ERR(s2mps11_clks->clk_np))
226 		return PTR_ERR(s2mps11_clks->clk_np);
227 
228 	for (i = 0; i < S2MPS11_CLKS_NUM; i++, s2mps11_clk++) {
229 		if (!clks_init[i].name)
230 			continue; /* Skip clocks not present in some devices */
231 		s2mps11_clk->iodev = iodev;
232 		s2mps11_clk->hw.init = &clks_init[i];
233 		s2mps11_clk->mask = 1 << i;
234 		s2mps11_clk->reg = s2mps11_reg;
235 
236 		s2mps11_clk->clk = devm_clk_register(&pdev->dev,
237 							&s2mps11_clk->hw);
238 		if (IS_ERR(s2mps11_clk->clk)) {
239 			dev_err(&pdev->dev, "Fail to register : %s\n",
240 						s2mps11_name(s2mps11_clk));
241 			ret = PTR_ERR(s2mps11_clk->clk);
242 			goto err_reg;
243 		}
244 
245 		s2mps11_clk->lookup = clkdev_alloc(s2mps11_clk->clk,
246 					s2mps11_name(s2mps11_clk), NULL);
247 		if (!s2mps11_clk->lookup) {
248 			ret = -ENOMEM;
249 			goto err_lup;
250 		}
251 
252 		clkdev_add(s2mps11_clk->lookup);
253 	}
254 
255 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
256 		/* Skip clocks not present on S2MPS14 */
257 		if (!clks_init[i].name)
258 			continue;
259 		clk_table[i] = s2mps11_clks[i].clk;
260 	}
261 
262 	clk_data.clks = clk_table;
263 	clk_data.clk_num = S2MPS11_CLKS_NUM;
264 	of_clk_add_provider(s2mps11_clks->clk_np, of_clk_src_onecell_get,
265 			&clk_data);
266 
267 	platform_set_drvdata(pdev, s2mps11_clks);
268 
269 	return ret;
270 err_lup:
271 	devm_clk_unregister(&pdev->dev, s2mps11_clk->clk);
272 err_reg:
273 	while (s2mps11_clk > s2mps11_clks) {
274 		if (s2mps11_clk->lookup) {
275 			clkdev_drop(s2mps11_clk->lookup);
276 			devm_clk_unregister(&pdev->dev, s2mps11_clk->clk);
277 		}
278 		s2mps11_clk--;
279 	}
280 
281 	return ret;
282 }
283 
284 static int s2mps11_clk_remove(struct platform_device *pdev)
285 {
286 	struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
287 	int i;
288 
289 	of_clk_del_provider(s2mps11_clks[0].clk_np);
290 	/* Drop the reference obtained in s2mps11_clk_parse_dt */
291 	of_node_put(s2mps11_clks[0].clk_np);
292 
293 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
294 		/* Skip clocks not present on S2MPS14 */
295 		if (!s2mps11_clks[i].lookup)
296 			continue;
297 		clkdev_drop(s2mps11_clks[i].lookup);
298 	}
299 
300 	return 0;
301 }
302 
303 static const struct platform_device_id s2mps11_clk_id[] = {
304 	{ "s2mps11-clk", S2MPS11X},
305 	{ "s2mps13-clk", S2MPS13X},
306 	{ "s2mps14-clk", S2MPS14X},
307 	{ "s5m8767-clk", S5M8767X},
308 	{ },
309 };
310 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
311 
312 static struct platform_driver s2mps11_clk_driver = {
313 	.driver = {
314 		.name  = "s2mps11-clk",
315 	},
316 	.probe = s2mps11_clk_probe,
317 	.remove = s2mps11_clk_remove,
318 	.id_table = s2mps11_clk_id,
319 };
320 
321 static int __init s2mps11_clk_init(void)
322 {
323 	return platform_driver_register(&s2mps11_clk_driver);
324 }
325 subsys_initcall(s2mps11_clk_init);
326 
327 static void __init s2mps11_clk_cleanup(void)
328 {
329 	platform_driver_unregister(&s2mps11_clk_driver);
330 }
331 module_exit(s2mps11_clk_cleanup);
332 
333 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
334 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
335 MODULE_LICENSE("GPL");
336