xref: /openbmc/linux/drivers/mfd/max8907.c (revision 86e281fc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * max8907.c - mfd driver for MAX8907
4  *
5  * Copyright (C) 2010 Gyungoh Yoo <jack.yoo@maxim-ic.com>
6  * Copyright (C) 2010-2012, NVIDIA CORPORATION. All rights reserved.
7  */
8 
9 #include <linux/err.h>
10 #include <linux/i2c.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/irq.h>
14 #include <linux/mfd/core.h>
15 #include <linux/mfd/max8907.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/regmap.h>
19 #include <linux/slab.h>
20 
21 static const struct mfd_cell max8907_cells[] = {
22 	{ .name = "max8907-regulator", },
23 	{ .name = "max8907-rtc", },
24 };
25 
26 static bool max8907_gen_is_volatile_reg(struct device *dev, unsigned int reg)
27 {
28 	switch (reg) {
29 	case MAX8907_REG_ON_OFF_IRQ1:
30 	case MAX8907_REG_ON_OFF_STAT:
31 	case MAX8907_REG_ON_OFF_IRQ2:
32 	case MAX8907_REG_CHG_IRQ1:
33 	case MAX8907_REG_CHG_IRQ2:
34 	case MAX8907_REG_CHG_STAT:
35 		return true;
36 	default:
37 		return false;
38 	}
39 }
40 
41 static bool max8907_gen_is_precious_reg(struct device *dev, unsigned int reg)
42 {
43 	switch (reg) {
44 	case MAX8907_REG_ON_OFF_IRQ1:
45 	case MAX8907_REG_ON_OFF_IRQ2:
46 	case MAX8907_REG_CHG_IRQ1:
47 	case MAX8907_REG_CHG_IRQ2:
48 		return true;
49 	default:
50 		return false;
51 	}
52 }
53 
54 static bool max8907_gen_is_writeable_reg(struct device *dev, unsigned int reg)
55 {
56 	return !max8907_gen_is_volatile_reg(dev, reg);
57 }
58 
59 static const struct regmap_config max8907_regmap_gen_config = {
60 	.reg_bits = 8,
61 	.val_bits = 8,
62 	.volatile_reg = max8907_gen_is_volatile_reg,
63 	.precious_reg = max8907_gen_is_precious_reg,
64 	.writeable_reg = max8907_gen_is_writeable_reg,
65 	.max_register = MAX8907_REG_LDO20VOUT,
66 	.cache_type = REGCACHE_RBTREE,
67 };
68 
69 static bool max8907_rtc_is_volatile_reg(struct device *dev, unsigned int reg)
70 {
71 	if (reg <= MAX8907_REG_RTC_YEAR2)
72 		return true;
73 
74 	switch (reg) {
75 	case MAX8907_REG_RTC_STATUS:
76 	case MAX8907_REG_RTC_IRQ:
77 		return true;
78 	default:
79 		return false;
80 	}
81 }
82 
83 static bool max8907_rtc_is_precious_reg(struct device *dev, unsigned int reg)
84 {
85 	switch (reg) {
86 	case MAX8907_REG_RTC_IRQ:
87 		return true;
88 	default:
89 		return false;
90 	}
91 }
92 
93 static bool max8907_rtc_is_writeable_reg(struct device *dev, unsigned int reg)
94 {
95 	switch (reg) {
96 	case MAX8907_REG_RTC_STATUS:
97 	case MAX8907_REG_RTC_IRQ:
98 		return false;
99 	default:
100 		return true;
101 	}
102 }
103 
104 static const struct regmap_config max8907_regmap_rtc_config = {
105 	.reg_bits = 8,
106 	.val_bits = 8,
107 	.volatile_reg = max8907_rtc_is_volatile_reg,
108 	.precious_reg = max8907_rtc_is_precious_reg,
109 	.writeable_reg = max8907_rtc_is_writeable_reg,
110 	.max_register = MAX8907_REG_MPL_CNTL,
111 	.cache_type = REGCACHE_RBTREE,
112 };
113 
114 static const struct regmap_irq max8907_chg_irqs[] = {
115 	{ .reg_offset = 0, .mask = 1 << 0, },
116 	{ .reg_offset = 0, .mask = 1 << 1, },
117 	{ .reg_offset = 0, .mask = 1 << 2, },
118 	{ .reg_offset = 1, .mask = 1 << 0, },
119 	{ .reg_offset = 1, .mask = 1 << 1, },
120 	{ .reg_offset = 1, .mask = 1 << 2, },
121 	{ .reg_offset = 1, .mask = 1 << 3, },
122 	{ .reg_offset = 1, .mask = 1 << 4, },
123 	{ .reg_offset = 1, .mask = 1 << 5, },
124 	{ .reg_offset = 1, .mask = 1 << 6, },
125 	{ .reg_offset = 1, .mask = 1 << 7, },
126 };
127 
128 static const struct regmap_irq_chip max8907_chg_irq_chip = {
129 	.name = "max8907 chg",
130 	.status_base = MAX8907_REG_CHG_IRQ1,
131 	.mask_base = MAX8907_REG_CHG_IRQ1_MASK,
132 	.wake_base = MAX8907_REG_CHG_IRQ1_MASK,
133 	.irq_reg_stride = MAX8907_REG_CHG_IRQ2 - MAX8907_REG_CHG_IRQ1,
134 	.num_regs = 2,
135 	.irqs = max8907_chg_irqs,
136 	.num_irqs = ARRAY_SIZE(max8907_chg_irqs),
137 };
138 
139 static const struct regmap_irq max8907_on_off_irqs[] = {
140 	{ .reg_offset = 0, .mask = 1 << 0, },
141 	{ .reg_offset = 0, .mask = 1 << 1, },
142 	{ .reg_offset = 0, .mask = 1 << 2, },
143 	{ .reg_offset = 0, .mask = 1 << 3, },
144 	{ .reg_offset = 0, .mask = 1 << 4, },
145 	{ .reg_offset = 0, .mask = 1 << 5, },
146 	{ .reg_offset = 0, .mask = 1 << 6, },
147 	{ .reg_offset = 0, .mask = 1 << 7, },
148 	{ .reg_offset = 1, .mask = 1 << 0, },
149 	{ .reg_offset = 1, .mask = 1 << 1, },
150 };
151 
152 static const struct regmap_irq_chip max8907_on_off_irq_chip = {
153 	.name = "max8907 on_off",
154 	.status_base = MAX8907_REG_ON_OFF_IRQ1,
155 	.mask_base = MAX8907_REG_ON_OFF_IRQ1_MASK,
156 	.irq_reg_stride = MAX8907_REG_ON_OFF_IRQ2 - MAX8907_REG_ON_OFF_IRQ1,
157 	.num_regs = 2,
158 	.irqs = max8907_on_off_irqs,
159 	.num_irqs = ARRAY_SIZE(max8907_on_off_irqs),
160 };
161 
162 static const struct regmap_irq max8907_rtc_irqs[] = {
163 	{ .reg_offset = 0, .mask = 1 << 2, },
164 	{ .reg_offset = 0, .mask = 1 << 3, },
165 };
166 
167 static const struct regmap_irq_chip max8907_rtc_irq_chip = {
168 	.name = "max8907 rtc",
169 	.status_base = MAX8907_REG_RTC_IRQ,
170 	.mask_base = MAX8907_REG_RTC_IRQ_MASK,
171 	.num_regs = 1,
172 	.irqs = max8907_rtc_irqs,
173 	.num_irqs = ARRAY_SIZE(max8907_rtc_irqs),
174 };
175 
176 static struct max8907 *max8907_pm_off;
177 static void max8907_power_off(void)
178 {
179 	regmap_update_bits(max8907_pm_off->regmap_gen, MAX8907_REG_RESET_CNFG,
180 			MAX8907_MASK_POWER_OFF, MAX8907_MASK_POWER_OFF);
181 }
182 
183 static int max8907_i2c_probe(struct i2c_client *i2c)
184 {
185 	struct max8907 *max8907;
186 	int ret;
187 	struct max8907_platform_data *pdata = dev_get_platdata(&i2c->dev);
188 	bool pm_off = false;
189 
190 	if (pdata)
191 		pm_off = pdata->pm_off;
192 	else if (i2c->dev.of_node)
193 		pm_off = of_property_read_bool(i2c->dev.of_node,
194 					"maxim,system-power-controller");
195 
196 	max8907 = devm_kzalloc(&i2c->dev, sizeof(struct max8907), GFP_KERNEL);
197 	if (!max8907) {
198 		ret = -ENOMEM;
199 		goto err_alloc_drvdata;
200 	}
201 
202 	max8907->dev = &i2c->dev;
203 	max8907->i2c_gen = i2c;
204 	i2c_set_clientdata(i2c, max8907);
205 	max8907->regmap_gen = devm_regmap_init_i2c(i2c,
206 						&max8907_regmap_gen_config);
207 	if (IS_ERR(max8907->regmap_gen)) {
208 		ret = PTR_ERR(max8907->regmap_gen);
209 		dev_err(&i2c->dev, "gen regmap init failed: %d\n", ret);
210 		goto err_regmap_gen;
211 	}
212 
213 	max8907->i2c_rtc = i2c_new_dummy_device(i2c->adapter, MAX8907_RTC_I2C_ADDR);
214 	if (IS_ERR(max8907->i2c_rtc)) {
215 		ret = PTR_ERR(max8907->i2c_rtc);
216 		goto err_dummy_rtc;
217 	}
218 	i2c_set_clientdata(max8907->i2c_rtc, max8907);
219 	max8907->regmap_rtc = devm_regmap_init_i2c(max8907->i2c_rtc,
220 						&max8907_regmap_rtc_config);
221 	if (IS_ERR(max8907->regmap_rtc)) {
222 		ret = PTR_ERR(max8907->regmap_rtc);
223 		dev_err(&i2c->dev, "rtc regmap init failed: %d\n", ret);
224 		goto err_regmap_rtc;
225 	}
226 
227 	ret = regmap_add_irq_chip(max8907->regmap_gen, max8907->i2c_gen->irq,
228 				  IRQF_ONESHOT | IRQF_SHARED,
229 				  -1, &max8907_chg_irq_chip,
230 				  &max8907->irqc_chg);
231 	if (ret != 0) {
232 		dev_err(&i2c->dev, "failed to add chg irq chip: %d\n", ret);
233 		goto err_irqc_chg;
234 	}
235 	ret = regmap_add_irq_chip(max8907->regmap_gen, max8907->i2c_gen->irq,
236 				  IRQF_ONESHOT | IRQF_SHARED, -1,
237 				  &max8907_on_off_irq_chip,
238 				  &max8907->irqc_on_off);
239 	if (ret != 0) {
240 		dev_err(&i2c->dev, "failed to add on off irq chip: %d\n", ret);
241 		goto err_irqc_on_off;
242 	}
243 	ret = regmap_add_irq_chip(max8907->regmap_rtc, max8907->i2c_gen->irq,
244 				  IRQF_ONESHOT | IRQF_SHARED, -1,
245 				  &max8907_rtc_irq_chip,
246 				  &max8907->irqc_rtc);
247 	if (ret != 0) {
248 		dev_err(&i2c->dev, "failed to add rtc irq chip: %d\n", ret);
249 		goto err_irqc_rtc;
250 	}
251 
252 	ret = mfd_add_devices(max8907->dev, -1, max8907_cells,
253 			      ARRAY_SIZE(max8907_cells), NULL, 0, NULL);
254 	if (ret != 0) {
255 		dev_err(&i2c->dev, "failed to add MFD devices %d\n", ret);
256 		goto err_add_devices;
257 	}
258 
259 	if (pm_off && !pm_power_off) {
260 		max8907_pm_off = max8907;
261 		pm_power_off = max8907_power_off;
262 	}
263 
264 	return 0;
265 
266 err_add_devices:
267 	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_rtc);
268 err_irqc_rtc:
269 	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_on_off);
270 err_irqc_on_off:
271 	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_chg);
272 err_irqc_chg:
273 err_regmap_rtc:
274 	i2c_unregister_device(max8907->i2c_rtc);
275 err_dummy_rtc:
276 err_regmap_gen:
277 err_alloc_drvdata:
278 	return ret;
279 }
280 
281 static void max8907_i2c_remove(struct i2c_client *i2c)
282 {
283 	struct max8907 *max8907 = i2c_get_clientdata(i2c);
284 
285 	mfd_remove_devices(max8907->dev);
286 
287 	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_rtc);
288 	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_on_off);
289 	regmap_del_irq_chip(max8907->i2c_gen->irq, max8907->irqc_chg);
290 
291 	i2c_unregister_device(max8907->i2c_rtc);
292 }
293 
294 #ifdef CONFIG_OF
295 static const struct of_device_id max8907_of_match[] = {
296 	{ .compatible = "maxim,max8907" },
297 	{ },
298 };
299 MODULE_DEVICE_TABLE(of, max8907_of_match);
300 #endif
301 
302 static const struct i2c_device_id max8907_i2c_id[] = {
303 	{"max8907", 0},
304 	{}
305 };
306 MODULE_DEVICE_TABLE(i2c, max8907_i2c_id);
307 
308 static struct i2c_driver max8907_i2c_driver = {
309 	.driver = {
310 		.name = "max8907",
311 		.of_match_table = of_match_ptr(max8907_of_match),
312 	},
313 	.probe = max8907_i2c_probe,
314 	.remove = max8907_i2c_remove,
315 	.id_table = max8907_i2c_id,
316 };
317 
318 static int __init max8907_i2c_init(void)
319 {
320 	int ret = -ENODEV;
321 
322 	ret = i2c_add_driver(&max8907_i2c_driver);
323 	if (ret != 0)
324 		pr_err("Failed to register I2C driver: %d\n", ret);
325 
326 	return ret;
327 }
328 subsys_initcall(max8907_i2c_init);
329 
330 static void __exit max8907_i2c_exit(void)
331 {
332 	i2c_del_driver(&max8907_i2c_driver);
333 }
334 module_exit(max8907_i2c_exit);
335 
336 MODULE_DESCRIPTION("MAX8907 multi-function core driver");
337 MODULE_AUTHOR("Gyungoh Yoo <jack.yoo@maxim-ic.com>");
338 MODULE_LICENSE("GPL v2");
339