xref: /openbmc/linux/drivers/clk/clk-s2mps11.c (revision b8d312aa)
1 // SPDX-License-Identifier: GPL-2.0+
2 //
3 // clk-s2mps11.c - Clock driver for S2MPS11.
4 //
5 // Copyright (C) 2013,2014 Samsung Electornics
6 
7 #include <linux/module.h>
8 #include <linux/err.h>
9 #include <linux/of.h>
10 #include <linux/clkdev.h>
11 #include <linux/regmap.h>
12 #include <linux/clk-provider.h>
13 #include <linux/platform_device.h>
14 #include <linux/mfd/samsung/s2mps11.h>
15 #include <linux/mfd/samsung/s2mps13.h>
16 #include <linux/mfd/samsung/s2mps14.h>
17 #include <linux/mfd/samsung/s5m8767.h>
18 #include <linux/mfd/samsung/core.h>
19 
20 #include <dt-bindings/clock/samsung,s2mps11.h>
21 
22 struct s2mps11_clk {
23 	struct sec_pmic_dev *iodev;
24 	struct device_node *clk_np;
25 	struct clk_hw hw;
26 	struct clk *clk;
27 	struct clk_lookup *lookup;
28 	u32 mask;
29 	unsigned int reg;
30 };
31 
32 static struct s2mps11_clk *to_s2mps11_clk(struct clk_hw *hw)
33 {
34 	return container_of(hw, struct s2mps11_clk, hw);
35 }
36 
37 static int s2mps11_clk_prepare(struct clk_hw *hw)
38 {
39 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
40 
41 	return regmap_update_bits(s2mps11->iodev->regmap_pmic,
42 				 s2mps11->reg,
43 				 s2mps11->mask, s2mps11->mask);
44 }
45 
46 static void s2mps11_clk_unprepare(struct clk_hw *hw)
47 {
48 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
49 
50 	regmap_update_bits(s2mps11->iodev->regmap_pmic, s2mps11->reg,
51 			   s2mps11->mask, ~s2mps11->mask);
52 }
53 
54 static int s2mps11_clk_is_prepared(struct clk_hw *hw)
55 {
56 	int ret;
57 	u32 val;
58 	struct s2mps11_clk *s2mps11 = to_s2mps11_clk(hw);
59 
60 	ret = regmap_read(s2mps11->iodev->regmap_pmic,
61 				s2mps11->reg, &val);
62 	if (ret < 0)
63 		return -EINVAL;
64 
65 	return val & s2mps11->mask;
66 }
67 
68 static unsigned long s2mps11_clk_recalc_rate(struct clk_hw *hw,
69 					     unsigned long parent_rate)
70 {
71 	return 32768;
72 }
73 
74 static const struct clk_ops s2mps11_clk_ops = {
75 	.prepare	= s2mps11_clk_prepare,
76 	.unprepare	= s2mps11_clk_unprepare,
77 	.is_prepared	= s2mps11_clk_is_prepared,
78 	.recalc_rate	= s2mps11_clk_recalc_rate,
79 };
80 
81 /* This s2mps11_clks_init tructure is common to s2mps11, s2mps13 and s2mps14 */
82 static struct clk_init_data s2mps11_clks_init[S2MPS11_CLKS_NUM] = {
83 	[S2MPS11_CLK_AP] = {
84 		.name = "s2mps11_ap",
85 		.ops = &s2mps11_clk_ops,
86 	},
87 	[S2MPS11_CLK_CP] = {
88 		.name = "s2mps11_cp",
89 		.ops = &s2mps11_clk_ops,
90 	},
91 	[S2MPS11_CLK_BT] = {
92 		.name = "s2mps11_bt",
93 		.ops = &s2mps11_clk_ops,
94 	},
95 };
96 
97 static struct device_node *s2mps11_clk_parse_dt(struct platform_device *pdev,
98 		struct clk_init_data *clks_init)
99 {
100 	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
101 	struct device_node *clk_np;
102 	int i;
103 
104 	if (!iodev->dev->of_node)
105 		return ERR_PTR(-EINVAL);
106 
107 	clk_np = of_get_child_by_name(iodev->dev->of_node, "clocks");
108 	if (!clk_np) {
109 		dev_err(&pdev->dev, "could not find clock sub-node\n");
110 		return ERR_PTR(-EINVAL);
111 	}
112 
113 	for (i = 0; i < S2MPS11_CLKS_NUM; i++)
114 		of_property_read_string_index(clk_np, "clock-output-names", i,
115 				&clks_init[i].name);
116 
117 	return clk_np;
118 }
119 
120 static int s2mps11_clk_probe(struct platform_device *pdev)
121 {
122 	struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent);
123 	struct s2mps11_clk *s2mps11_clks;
124 	struct clk_hw_onecell_data *clk_data;
125 	unsigned int s2mps11_reg;
126 	int i, ret = 0;
127 	enum sec_device_type hwid = platform_get_device_id(pdev)->driver_data;
128 
129 	s2mps11_clks = devm_kcalloc(&pdev->dev, S2MPS11_CLKS_NUM,
130 				sizeof(*s2mps11_clks), GFP_KERNEL);
131 	if (!s2mps11_clks)
132 		return -ENOMEM;
133 
134 	clk_data = devm_kzalloc(&pdev->dev,
135 				struct_size(clk_data, hws, S2MPS11_CLKS_NUM),
136 				GFP_KERNEL);
137 	if (!clk_data)
138 		return -ENOMEM;
139 
140 	switch (hwid) {
141 	case S2MPS11X:
142 		s2mps11_reg = S2MPS11_REG_RTC_CTRL;
143 		break;
144 	case S2MPS13X:
145 		s2mps11_reg = S2MPS13_REG_RTCCTRL;
146 		break;
147 	case S2MPS14X:
148 		s2mps11_reg = S2MPS14_REG_RTCCTRL;
149 		break;
150 	case S5M8767X:
151 		s2mps11_reg = S5M8767_REG_CTRL1;
152 		break;
153 	default:
154 		dev_err(&pdev->dev, "Invalid device type\n");
155 		return -EINVAL;
156 	}
157 
158 	/* Store clocks of_node in first element of s2mps11_clks array */
159 	s2mps11_clks->clk_np = s2mps11_clk_parse_dt(pdev, s2mps11_clks_init);
160 	if (IS_ERR(s2mps11_clks->clk_np))
161 		return PTR_ERR(s2mps11_clks->clk_np);
162 
163 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
164 		if (i == S2MPS11_CLK_CP && hwid == S2MPS14X)
165 			continue; /* Skip clocks not present in some devices */
166 		s2mps11_clks[i].iodev = iodev;
167 		s2mps11_clks[i].hw.init = &s2mps11_clks_init[i];
168 		s2mps11_clks[i].mask = 1 << i;
169 		s2mps11_clks[i].reg = s2mps11_reg;
170 
171 		s2mps11_clks[i].clk = devm_clk_register(&pdev->dev,
172 							&s2mps11_clks[i].hw);
173 		if (IS_ERR(s2mps11_clks[i].clk)) {
174 			dev_err(&pdev->dev, "Fail to register : %s\n",
175 						s2mps11_clks_init[i].name);
176 			ret = PTR_ERR(s2mps11_clks[i].clk);
177 			goto err_reg;
178 		}
179 
180 		s2mps11_clks[i].lookup = clkdev_hw_create(&s2mps11_clks[i].hw,
181 					s2mps11_clks_init[i].name, NULL);
182 		if (!s2mps11_clks[i].lookup) {
183 			ret = -ENOMEM;
184 			goto err_reg;
185 		}
186 		clk_data->hws[i] = &s2mps11_clks[i].hw;
187 	}
188 
189 	clk_data->num = S2MPS11_CLKS_NUM;
190 	of_clk_add_hw_provider(s2mps11_clks->clk_np, of_clk_hw_onecell_get,
191 			       clk_data);
192 
193 	platform_set_drvdata(pdev, s2mps11_clks);
194 
195 	return ret;
196 
197 err_reg:
198 	while (--i >= 0)
199 		clkdev_drop(s2mps11_clks[i].lookup);
200 
201 	return ret;
202 }
203 
204 static int s2mps11_clk_remove(struct platform_device *pdev)
205 {
206 	struct s2mps11_clk *s2mps11_clks = platform_get_drvdata(pdev);
207 	int i;
208 
209 	of_clk_del_provider(s2mps11_clks[0].clk_np);
210 	/* Drop the reference obtained in s2mps11_clk_parse_dt */
211 	of_node_put(s2mps11_clks[0].clk_np);
212 
213 	for (i = 0; i < S2MPS11_CLKS_NUM; i++) {
214 		/* Skip clocks not present on S2MPS14 */
215 		if (!s2mps11_clks[i].lookup)
216 			continue;
217 		clkdev_drop(s2mps11_clks[i].lookup);
218 	}
219 
220 	return 0;
221 }
222 
223 static const struct platform_device_id s2mps11_clk_id[] = {
224 	{ "s2mps11-clk", S2MPS11X},
225 	{ "s2mps13-clk", S2MPS13X},
226 	{ "s2mps14-clk", S2MPS14X},
227 	{ "s5m8767-clk", S5M8767X},
228 	{ },
229 };
230 MODULE_DEVICE_TABLE(platform, s2mps11_clk_id);
231 
232 #ifdef CONFIG_OF
233 /*
234  * Device is instantiated through parent MFD device and device matching is done
235  * through platform_device_id.
236  *
237  * However if device's DT node contains proper clock compatible and driver is
238  * built as a module, then the *module* matching will be done trough DT aliases.
239  * This requires of_device_id table.  In the same time this will not change the
240  * actual *device* matching so do not add .of_match_table.
241  */
242 static const struct of_device_id s2mps11_dt_match[] __used = {
243 	{
244 		.compatible = "samsung,s2mps11-clk",
245 		.data = (void *)S2MPS11X,
246 	}, {
247 		.compatible = "samsung,s2mps13-clk",
248 		.data = (void *)S2MPS13X,
249 	}, {
250 		.compatible = "samsung,s2mps14-clk",
251 		.data = (void *)S2MPS14X,
252 	}, {
253 		.compatible = "samsung,s5m8767-clk",
254 		.data = (void *)S5M8767X,
255 	}, {
256 		/* Sentinel */
257 	},
258 };
259 MODULE_DEVICE_TABLE(of, s2mps11_dt_match);
260 #endif
261 
262 static struct platform_driver s2mps11_clk_driver = {
263 	.driver = {
264 		.name  = "s2mps11-clk",
265 	},
266 	.probe = s2mps11_clk_probe,
267 	.remove = s2mps11_clk_remove,
268 	.id_table = s2mps11_clk_id,
269 };
270 
271 static int __init s2mps11_clk_init(void)
272 {
273 	return platform_driver_register(&s2mps11_clk_driver);
274 }
275 subsys_initcall(s2mps11_clk_init);
276 
277 static void __exit s2mps11_clk_cleanup(void)
278 {
279 	platform_driver_unregister(&s2mps11_clk_driver);
280 }
281 module_exit(s2mps11_clk_cleanup);
282 
283 MODULE_DESCRIPTION("S2MPS11 Clock Driver");
284 MODULE_AUTHOR("Yadwinder Singh Brar <yadi.brar@samsung.com>");
285 MODULE_LICENSE("GPL");
286