1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ROHM BD9571MWV-M and BD9574MWF-M regulator driver
4  *
5  * Copyright (C) 2017 Marek Vasut <marek.vasut+renesas@gmail.com>
6  *
7  * Based on the TPS65086 driver
8  *
9  * NOTE: VD09 is missing
10  */
11 
12 #include <linux/mfd/rohm-generic.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/regulator/driver.h>
17 
18 #include <linux/mfd/bd9571mwv.h>
19 
20 struct bd9571mwv_reg {
21 	struct regmap *regmap;
22 
23 	/* DDR Backup Power */
24 	u8 bkup_mode_cnt_keepon;	/* from "rohm,ddr-backup-power" */
25 	u8 bkup_mode_cnt_saved;
26 	bool bkup_mode_enabled;
27 
28 	/* Power switch type */
29 	bool rstbmode_level;
30 	bool rstbmode_pulse;
31 };
32 
33 enum bd9571mwv_regulators { VD09, VD18, VD25, VD33, DVFS };
34 
35 #define BD9571MWV_REG(_name, _of, _id, _ops, _vr, _vm, _nv, _min, _step, _lmin)\
36 	{							\
37 		.name			= _name,		\
38 		.of_match		= of_match_ptr(_of),	\
39 		.regulators_node	= "regulators",		\
40 		.id			= _id,			\
41 		.ops			= &_ops,		\
42 		.n_voltages		= _nv,			\
43 		.type			= REGULATOR_VOLTAGE,	\
44 		.owner			= THIS_MODULE,		\
45 		.vsel_reg		= _vr,			\
46 		.vsel_mask		= _vm,			\
47 		.min_uV			= _min,			\
48 		.uV_step		= _step,		\
49 		.linear_min_sel		= _lmin,		\
50 	}
51 
52 static int bd9571mwv_avs_get_moni_state(struct regulator_dev *rdev)
53 {
54 	unsigned int val;
55 	int ret;
56 
57 	ret = regmap_read(rdev->regmap, BD9571MWV_AVS_SET_MONI, &val);
58 	if (ret != 0)
59 		return ret;
60 
61 	return val & BD9571MWV_AVS_SET_MONI_MASK;
62 }
63 
64 static int bd9571mwv_avs_set_voltage_sel_regmap(struct regulator_dev *rdev,
65 						unsigned int sel)
66 {
67 	int ret;
68 
69 	ret = bd9571mwv_avs_get_moni_state(rdev);
70 	if (ret < 0)
71 		return ret;
72 
73 	return regmap_write_bits(rdev->regmap, BD9571MWV_AVS_VD09_VID(ret),
74 				 rdev->desc->vsel_mask, sel);
75 }
76 
77 static int bd9571mwv_avs_get_voltage_sel_regmap(struct regulator_dev *rdev)
78 {
79 	unsigned int val;
80 	int ret;
81 
82 	ret = bd9571mwv_avs_get_moni_state(rdev);
83 	if (ret < 0)
84 		return ret;
85 
86 	ret = regmap_read(rdev->regmap, BD9571MWV_AVS_VD09_VID(ret), &val);
87 	if (ret != 0)
88 		return ret;
89 
90 	val &= rdev->desc->vsel_mask;
91 	val >>= ffs(rdev->desc->vsel_mask) - 1;
92 
93 	return val;
94 }
95 
96 static int bd9571mwv_reg_set_voltage_sel_regmap(struct regulator_dev *rdev,
97 						unsigned int sel)
98 {
99 	return regmap_write_bits(rdev->regmap, BD9571MWV_DVFS_SETVID,
100 				 rdev->desc->vsel_mask, sel);
101 }
102 
103 /* Operations permitted on AVS voltage regulator */
104 static const struct regulator_ops avs_ops = {
105 	.set_voltage_sel	= bd9571mwv_avs_set_voltage_sel_regmap,
106 	.map_voltage		= regulator_map_voltage_linear,
107 	.get_voltage_sel	= bd9571mwv_avs_get_voltage_sel_regmap,
108 	.list_voltage		= regulator_list_voltage_linear,
109 };
110 
111 /* Operations permitted on voltage regulators */
112 static const struct regulator_ops reg_ops = {
113 	.set_voltage_sel	= bd9571mwv_reg_set_voltage_sel_regmap,
114 	.map_voltage		= regulator_map_voltage_linear,
115 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
116 	.list_voltage		= regulator_list_voltage_linear,
117 };
118 
119 /* Operations permitted on voltage monitors */
120 static const struct regulator_ops vid_ops = {
121 	.map_voltage		= regulator_map_voltage_linear,
122 	.get_voltage_sel	= regulator_get_voltage_sel_regmap,
123 	.list_voltage		= regulator_list_voltage_linear,
124 };
125 
126 static const struct regulator_desc regulators[] = {
127 	BD9571MWV_REG("VD09", "vd09", VD09, avs_ops, 0, 0x7f,
128 		      0x6f, 600000, 10000, 0x3c),
129 	BD9571MWV_REG("VD18", "vd18", VD18, vid_ops, BD9571MWV_VD18_VID, 0xf,
130 		      16, 1625000, 25000, 0),
131 	BD9571MWV_REG("VD25", "vd25", VD25, vid_ops, BD9571MWV_VD25_VID, 0xf,
132 		      16, 2150000, 50000, 0),
133 	BD9571MWV_REG("VD33", "vd33", VD33, vid_ops, BD9571MWV_VD33_VID, 0xf,
134 		      11, 2800000, 100000, 0),
135 	BD9571MWV_REG("DVFS", "dvfs", DVFS, reg_ops,
136 		      BD9571MWV_DVFS_MONIVDAC, 0x7f,
137 		      0x6f, 600000, 10000, 0x3c),
138 };
139 
140 #ifdef CONFIG_PM_SLEEP
141 static int bd9571mwv_bkup_mode_read(struct bd9571mwv_reg *bdreg,
142 				    unsigned int *mode)
143 {
144 	int ret;
145 
146 	ret = regmap_read(bdreg->regmap, BD9571MWV_BKUP_MODE_CNT, mode);
147 	if (ret) {
148 		dev_err(regmap_get_device(bdreg->regmap),
149 			"failed to read backup mode (%d)\n", ret);
150 		return ret;
151 	}
152 
153 	return 0;
154 }
155 
156 static int bd9571mwv_bkup_mode_write(struct bd9571mwv_reg *bdreg,
157 				     unsigned int mode)
158 {
159 	int ret;
160 
161 	ret = regmap_write(bdreg->regmap, BD9571MWV_BKUP_MODE_CNT, mode);
162 	if (ret) {
163 		dev_err(regmap_get_device(bdreg->regmap),
164 			"failed to configure backup mode 0x%x (%d)\n",
165 			mode, ret);
166 		return ret;
167 	}
168 
169 	return 0;
170 }
171 
172 static ssize_t backup_mode_show(struct device *dev,
173 				struct device_attribute *attr, char *buf)
174 {
175 	struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev);
176 
177 	return sysfs_emit(buf, "%s\n", bdreg->bkup_mode_enabled ? "on" : "off");
178 }
179 
180 static ssize_t backup_mode_store(struct device *dev,
181 				 struct device_attribute *attr,
182 				 const char *buf, size_t count)
183 {
184 	struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev);
185 	unsigned int mode;
186 	int ret;
187 
188 	if (!count)
189 		return 0;
190 
191 	ret = kstrtobool(buf, &bdreg->bkup_mode_enabled);
192 	if (ret)
193 		return ret;
194 
195 	if (!bdreg->rstbmode_level)
196 		return count;
197 
198 	/*
199 	 * Configure DDR Backup Mode, to change the role of the accessory power
200 	 * switch from a power switch to a wake-up switch, or vice versa
201 	 */
202 	ret = bd9571mwv_bkup_mode_read(bdreg, &mode);
203 	if (ret)
204 		return ret;
205 
206 	mode &= ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK;
207 	if (bdreg->bkup_mode_enabled)
208 		mode |= bdreg->bkup_mode_cnt_keepon;
209 
210 	ret = bd9571mwv_bkup_mode_write(bdreg, mode);
211 	if (ret)
212 		return ret;
213 
214 	return count;
215 }
216 
217 static DEVICE_ATTR_RW(backup_mode);
218 
219 static int bd9571mwv_suspend(struct device *dev)
220 {
221 	struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev);
222 	unsigned int mode;
223 	int ret;
224 
225 	if (!bdreg->bkup_mode_enabled)
226 		return 0;
227 
228 	/* Save DDR Backup Mode */
229 	ret = bd9571mwv_bkup_mode_read(bdreg, &mode);
230 	if (ret)
231 		return ret;
232 
233 	bdreg->bkup_mode_cnt_saved = mode;
234 
235 	if (!bdreg->rstbmode_pulse)
236 		return 0;
237 
238 	/* Enable DDR Backup Mode */
239 	mode &= ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK;
240 	mode |= bdreg->bkup_mode_cnt_keepon;
241 
242 	if (mode != bdreg->bkup_mode_cnt_saved)
243 		return bd9571mwv_bkup_mode_write(bdreg, mode);
244 
245 	return 0;
246 }
247 
248 static int bd9571mwv_resume(struct device *dev)
249 {
250 	struct bd9571mwv_reg *bdreg = dev_get_drvdata(dev);
251 
252 	if (!bdreg->bkup_mode_enabled)
253 		return 0;
254 
255 	/* Restore DDR Backup Mode */
256 	return bd9571mwv_bkup_mode_write(bdreg, bdreg->bkup_mode_cnt_saved);
257 }
258 
259 static const struct dev_pm_ops bd9571mwv_pm  = {
260 	SET_SYSTEM_SLEEP_PM_OPS(bd9571mwv_suspend, bd9571mwv_resume)
261 };
262 
263 static int bd9571mwv_regulator_remove(struct platform_device *pdev)
264 {
265 	device_remove_file(&pdev->dev, &dev_attr_backup_mode);
266 	return 0;
267 }
268 #define DEV_PM_OPS	&bd9571mwv_pm
269 #else
270 #define DEV_PM_OPS	NULL
271 #define bd9571mwv_regulator_remove	NULL
272 #endif /* CONFIG_PM_SLEEP */
273 
274 static int bd9571mwv_regulator_probe(struct platform_device *pdev)
275 {
276 	struct regulator_config config = { };
277 	struct bd9571mwv_reg *bdreg;
278 	struct regulator_dev *rdev;
279 	unsigned int val;
280 	int i;
281 	enum rohm_chip_type chip = platform_get_device_id(pdev)->driver_data;
282 
283 	bdreg = devm_kzalloc(&pdev->dev, sizeof(*bdreg), GFP_KERNEL);
284 	if (!bdreg)
285 		return -ENOMEM;
286 
287 	bdreg->regmap = dev_get_regmap(pdev->dev.parent, NULL);
288 
289 	platform_set_drvdata(pdev, bdreg);
290 
291 	config.dev = &pdev->dev;
292 	config.dev->of_node = pdev->dev.parent->of_node;
293 	config.driver_data = bdreg;
294 	config.regmap = bdreg->regmap;
295 
296 	for (i = 0; i < ARRAY_SIZE(regulators); i++) {
297 		/* BD9574MWF supports DVFS only */
298 		if (chip == ROHM_CHIP_TYPE_BD9574 && regulators[i].id != DVFS)
299 			continue;
300 		rdev = devm_regulator_register(&pdev->dev, &regulators[i],
301 					       &config);
302 		if (IS_ERR(rdev)) {
303 			dev_err(&pdev->dev, "failed to register %s regulator\n",
304 				regulators[i].name);
305 			return PTR_ERR(rdev);
306 		}
307 	}
308 
309 	val = 0;
310 	of_property_read_u32(config.dev->of_node, "rohm,ddr-backup-power", &val);
311 	if (val & ~BD9571MWV_BKUP_MODE_CNT_KEEPON_MASK) {
312 		dev_err(&pdev->dev, "invalid %s mode %u\n",
313 			"rohm,ddr-backup-power", val);
314 		return -EINVAL;
315 	}
316 	bdreg->bkup_mode_cnt_keepon = val;
317 
318 	bdreg->rstbmode_level = of_property_read_bool(config.dev->of_node,
319 						      "rohm,rstbmode-level");
320 	bdreg->rstbmode_pulse = of_property_read_bool(config.dev->of_node,
321 						      "rohm,rstbmode-pulse");
322 	if (bdreg->rstbmode_level && bdreg->rstbmode_pulse) {
323 		dev_err(&pdev->dev, "only one rohm,rstbmode-* may be specified");
324 		return -EINVAL;
325 	}
326 
327 #ifdef CONFIG_PM_SLEEP
328 	if (bdreg->bkup_mode_cnt_keepon) {
329 		int ret;
330 
331 		/*
332 		 * Backup mode is enabled by default in pulse mode, but needs
333 		 * explicit user setup in level mode.
334 		 */
335 		bdreg->bkup_mode_enabled = bdreg->rstbmode_pulse;
336 
337 		ret = device_create_file(&pdev->dev, &dev_attr_backup_mode);
338 		if (ret)
339 			return ret;
340 	}
341 #endif /* CONFIG_PM_SLEEP */
342 
343 	return 0;
344 }
345 
346 static const struct platform_device_id bd9571mwv_regulator_id_table[] = {
347 	{ "bd9571mwv-regulator", ROHM_CHIP_TYPE_BD9571 },
348 	{ "bd9574mwf-regulator", ROHM_CHIP_TYPE_BD9574 },
349 	{ /* sentinel */ }
350 };
351 MODULE_DEVICE_TABLE(platform, bd9571mwv_regulator_id_table);
352 
353 static struct platform_driver bd9571mwv_regulator_driver = {
354 	.driver = {
355 		.name = "bd9571mwv-regulator",
356 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
357 		.pm = DEV_PM_OPS,
358 	},
359 	.probe = bd9571mwv_regulator_probe,
360 	.remove = bd9571mwv_regulator_remove,
361 	.id_table = bd9571mwv_regulator_id_table,
362 };
363 module_platform_driver(bd9571mwv_regulator_driver);
364 
365 MODULE_AUTHOR("Marek Vasut <marek.vasut+renesas@gmail.com>");
366 MODULE_DESCRIPTION("BD9571MWV Regulator driver");
367 MODULE_LICENSE("GPL v2");
368