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 enum {
32 	S2MPS11_CLK_AP = 0,
33 	S2MPS11_CLK_CP,
34 	S2MPS11_CLK_BT,
35 	S2MPS11_CLKS_NUM,
36 };
37 
38 struct s2mps11_clk {
39 	struct sec_pmic_dev *iodev;
40 	struct device_node *clk_np;
41 	struct clk_hw hw;
42 	struct clk *clk;
43 	struct clk_lookup *lookup;
44 	u32 mask;
45 	unsigned int reg;
46 };
47 
to_s2mps11_clk(struct clk_hw * hw)48 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
49 {
50 	return container_of(hw, struct s2mps11_clk, hw);
51 }
52 
s2mps11_clk_prepare(struct clk_hw * hw)53 static int s2mps11_clk_prepare(struct clk_hw *hw)
54 {
55 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
56 
57 	return regmap_update_bits(s2mps11->iodev->regmap_pmic,
58 				 s2mps11->reg,
59 				 s2mps11->mask, s2mps11->mask);
60 }
61 
s2mps11_clk_unprepare(struct clk_hw * hw)62 static void s2mps11_clk_unprepare(struct clk_hw *hw)
63 {
64 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
65 
66 	regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
67 			   s2mps11->mask, ~s2mps11->mask);
68 }
69 
s2mps11_clk_is_prepared(struct clk_hw * hw)70 static int s2mps11_clk_is_prepared(struct clk_hw *hw)
71 {
72 	int ret;
73 	u32 val;
74 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
75 
76 	ret = regmap_read(s2mps11->iodev->regmap_pmic,
77 				s2mps11->reg, &val);
78 	if (ret < 0)
79 		return -EINVAL;
80 
81 	return val & s2mps11->mask;
82 }
83 
s2mps11_clk_recalc_rate(struct clk_hw * hw,unsigned long parent_rate)84 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
85 					     unsigned long parent_rate)
86 {
87 	return 32768;
88 }
89 
90 static struct clk_ops s2mps11_clk_ops = {
91 	.prepare	= s2mps11_clk_prepare,
92 	.unprepare	= s2mps11_clk_unprepare,
93 	.is_prepared	= s2mps11_clk_is_prepared,
94 	.recalc_rate	= s2mps11_clk_recalc_rate,
95 };
96 
97 /* This s2mps11_clks_init tructure is common to s2mps11, s2mps13 and s2mps14 */
98 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
99 	[S2MPS11_CLK_AP] = {
100 		.name = "s2mps11_ap",
101 		.ops = &s2mps11_clk_ops,
102 	},
103 	[S2MPS11_CLK_CP] = {
104 		.name = "s2mps11_cp",
105 		.ops = &s2mps11_clk_ops,
106 	},
107 	[S2MPS11_CLK_BT] = {
108 		.name = "s2mps11_bt",
109 		.ops = &s2mps11_clk_ops,
110 	},
111 };
112 
s2mps11_clk_parse_dt(struct platform_device * pdev,struct clk_init_data * clks_init)113 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
114 		struct clk_init_data *clks_init)
115 {
116 	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
117 	struct device_node *clk_np;
118 	int i;
119 
120 	if (!iodev->dev->of_node)
121 		return ERR_PTR(-EINVAL);
122 
123 	clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
124 	if (!clk_np) {
125 		dev_err(&pdev->dev, "could not find clock sub-node\n");
126 		return ERR_PTR(-EINVAL);
127 	}
128 
129 	for (i = 0; i < S2MPS11_CLKS_NUM; i++)
130 		of_property_read_string_index(clk_np, "clock-output-names", i,
131 				&clks_init[i].name);
132 
133 	return clk_np;
134 }
135 
s2mps11_clk_probe(struct platform_device * pdev)136 static int s2mps11_clk_probe(struct platform_device *pdev)
137 {
138 	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
139 	struct s2mps11_clk *s2mps11_clks;
140 	struct clk_hw_onecell_data *clk_data;
141 	unsigned int s2mps11_reg;
142 	int i, ret = 0;
143 	enum sec_device_type hwid = platform_get_device_id(pdev)->driver_data;
144 
145 	s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
146 				sizeof(*s2mps11_clks), GFP_KERNEL);
147 	if (!s2mps11_clks)
148 		return -ENOMEM;
149 
150 	clk_data = devm_kzalloc(&pdev->dev,
151 				struct_size(clk_data, hws, S2MPS11_CLKS_NUM),
152 				GFP_KERNEL);
153 	if (!clk_data)
154 		return -ENOMEM;
155 
156 	switch (hwid) {
157 	case S2MPS11X:
158 		s2mps11_reg = S2MPS11_REG_RTC_CTRL;
159 		break;
160 	case S2MPS13X:
161 		s2mps11_reg = S2MPS13_REG_RTCCTRL;
162 		break;
163 	case S2MPS14X:
164 		s2mps11_reg = S2MPS14_REG_RTCCTRL;
165 		break;
166 	case S5M8767X:
167 		s2mps11_reg = S5M8767_REG_CTRL1;
168 		break;
169 	default:
170 		dev_err(&pdev->dev, "Invalid device type\n");
171 		return -EINVAL;
172 	}
173 
174 	/* Store clocks of_node in first element of s2mps11_clks array */
175 	s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, s2mps11_clks_init);
176 	if (IS_ERR(s2mps11_clks->clk_np))
177 		return PTR_ERR(s2mps11_clks->clk_np);
178 
179 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
180 		if (i == S2MPS11_CLK_CP && hwid == S2MPS14X)
181 			continue; /* Skip clocks not present in some devices */
182 		s2mps11_clks[i].iodev = iodev;
183 		s2mps11_clks[i].hw.init = &s2mps11_clks_init[i];
184 		s2mps11_clks[i].mask = 1 << i;
185 		s2mps11_clks[i].reg = s2mps11_reg;
186 
187 		s2mps11_clks[i].clk = devm_clk_register(&pdev->dev,
188 							&s2mps11_clks[i].hw);
189 		if (IS_ERR(s2mps11_clks[i].clk)) {
190 			dev_err(&pdev->dev, "Fail to register : %s\n",
191 						s2mps11_clks_init[i].name);
192 			ret = PTR_ERR(s2mps11_clks[i].clk);
193 			goto err_reg;
194 		}
195 
196 		s2mps11_clks[i].lookup = clkdev_hw_create(&s2mps11_clks[i].hw,
197 					s2mps11_clks_init[i].name, NULL);
198 		if (!s2mps11_clks[i].lookup) {
199 			ret = -ENOMEM;
200 			goto err_reg;
201 		}
202 		clk_data->hws[i] = &s2mps11_clks[i].hw;
203 	}
204 
205 	clk_data->num = S2MPS11_CLKS_NUM;
206 	of_clk_add_hw_provider(s2mps11_clks->clk_np, of_clk_hw_onecell_get,
207 			       clk_data);
208 
209 	platform_set_drvdata(pdev, s2mps11_clks);
210 
211 	return ret;
212 
213 err_reg:
214 	of_node_put(s2mps11_clks[0].clk_np);
215 	while (--i >= 0)
216 		clkdev_drop(s2mps11_clks[i].lookup);
217 
218 	return ret;
219 }
220 
s2mps11_clk_remove(struct platform_device * pdev)221 static int s2mps11_clk_remove(struct platform_device *pdev)
222 {
223 	struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
224 	int i;
225 
226 	of_clk_del_provider(s2mps11_clks[0].clk_np);
227 	/* Drop the reference obtained in s2mps11_clk_parse_dt */
228 	of_node_put(s2mps11_clks[0].clk_np);
229 
230 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
231 		/* Skip clocks not present on S2MPS14 */
232 		if (!s2mps11_clks[i].lookup)
233 			continue;
234 		clkdev_drop(s2mps11_clks[i].lookup);
235 	}
236 
237 	return 0;
238 }
239 
240 static const struct platform_device_id s2mps11_clk_id[] = {
241 	{ "s2mps11-clk", S2MPS11X},
242 	{ "s2mps13-clk", S2MPS13X},
243 	{ "s2mps14-clk", S2MPS14X},
244 	{ "s5m8767-clk", S5M8767X},
245 	{ },
246 };
247 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
248 
249 #ifdef CONFIG_OF
250 /*
251  * Device is instantiated through parent MFD device and device matching is done
252  * through platform_device_id.
253  *
254  * However if device's DT node contains proper clock compatible and driver is
255  * built as a module, then the *module* matching will be done trough DT aliases.
256  * This requires of_device_id table.  In the same time this will not change the
257  * actual *device* matching so do not add .of_match_table.
258  */
259 static const struct of_device_id s2mps11_dt_match[] __used = {
260 	{
261 		.compatible = "samsung,s2mps11-clk",
262 		.data = (void *)S2MPS11X,
263 	}, {
264 		.compatible = "samsung,s2mps13-clk",
265 		.data = (void *)S2MPS13X,
266 	}, {
267 		.compatible = "samsung,s2mps14-clk",
268 		.data = (void *)S2MPS14X,
269 	}, {
270 		.compatible = "samsung,s5m8767-clk",
271 		.data = (void *)S5M8767X,
272 	}, {
273 		/* Sentinel */
274 	},
275 };
276 MODULE_DEVICE_TABLE(of, s2mps11_dt_match);
277 #endif
278 
279 static struct platform_driver s2mps11_clk_driver = {
280 	.driver = {
281 		.name  = "s2mps11-clk",
282 	},
283 	.probe = s2mps11_clk_probe,
284 	.remove = s2mps11_clk_remove,
285 	.id_table = s2mps11_clk_id,
286 };
287 
s2mps11_clk_init(void)288 static int __init s2mps11_clk_init(void)
289 {
290 	return platform_driver_register(&s2mps11_clk_driver);
291 }
292 subsys_initcall(s2mps11_clk_init);
293 
s2mps11_clk_cleanup(void)294 static void __exit s2mps11_clk_cleanup(void)
295 {
296 	platform_driver_unregister(&s2mps11_clk_driver);
297 }
298 module_exit(s2mps11_clk_cleanup);
299 
300 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
301 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
302 MODULE_LICENSE("GPL");
303