Merge tag 'ipsec-2023-10-17' of git://git.kernel.org/pub/scm/linux/kernel/git/klasser...
[platform/kernel/linux-starfive.git] / drivers / regulator / mt6331-regulator.c
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (c) 2022 Collabora Ltd.
4 // Author: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
5 //
6 // Based on mt6323-regulator.c,
7 //     Copyright (c) 2016 MediaTek Inc.
8 //
9
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/regmap.h>
14 #include <linux/mfd/mt6397/core.h>
15 #include <linux/mfd/mt6331/registers.h>
16 #include <linux/regulator/driver.h>
17 #include <linux/regulator/machine.h>
18 #include <linux/regulator/mt6331-regulator.h>
19 #include <linux/regulator/of_regulator.h>
20
21 #define MT6331_LDO_MODE_NORMAL  0
22 #define MT6331_LDO_MODE_LP      1
23
24 /*
25  * MT6331 regulators information
26  *
27  * @desc: standard fields of regulator description.
28  * @qi: Mask for query enable signal status of regulators
29  * @vselon_reg: Register sections for hardware control mode of bucks
30  * @vselctrl_reg: Register for controlling the buck control mode.
31  * @vselctrl_mask: Mask for query buck's voltage control mode.
32  * @status_reg: Register for regulator enable status where qi unavailable
33  * @status_mask: Mask for querying regulator enable status
34  */
35 struct mt6331_regulator_info {
36         struct regulator_desc desc;
37         u32 qi;
38         u32 vselon_reg;
39         u32 vselctrl_reg;
40         u32 vselctrl_mask;
41         u32 modeset_reg;
42         u32 modeset_mask;
43         u32 status_reg;
44         u32 status_mask;
45 };
46
47 #define MT6331_BUCK(match, vreg, min, max, step, volt_ranges, enreg,    \
48                 vosel, vosel_mask, voselon, vosel_ctrl)                 \
49 [MT6331_ID_##vreg] = {                                                  \
50         .desc = {                                                       \
51                 .name = #vreg,                                          \
52                 .of_match = of_match_ptr(match),                        \
53                 .ops = &mt6331_volt_range_ops,                          \
54                 .type = REGULATOR_VOLTAGE,                              \
55                 .id = MT6331_ID_##vreg,                                 \
56                 .owner = THIS_MODULE,                                   \
57                 .n_voltages = (max - min)/step + 1,                     \
58                 .linear_ranges = volt_ranges,                           \
59                 .n_linear_ranges = ARRAY_SIZE(volt_ranges),             \
60                 .vsel_reg = vosel,                                      \
61                 .vsel_mask = vosel_mask,                                \
62                 .enable_reg = enreg,                                    \
63                 .enable_mask = BIT(0),                                  \
64         },                                                              \
65         .qi = BIT(13),                                                  \
66         .vselon_reg = voselon,                                          \
67         .vselctrl_reg = vosel_ctrl,                                     \
68         .vselctrl_mask = BIT(1),                                        \
69         .status_mask = 0,                                               \
70 }
71
72 #define MT6331_LDO_AO(match, vreg, ldo_volt_table, vosel, vosel_mask)   \
73 [MT6331_ID_##vreg] = {                                                  \
74         .desc = {                                                       \
75                 .name = #vreg,                                          \
76                 .of_match = of_match_ptr(match),                        \
77                 .ops = &mt6331_volt_table_ao_ops,                       \
78                 .type = REGULATOR_VOLTAGE,                              \
79                 .id = MT6331_ID_##vreg,                                 \
80                 .owner = THIS_MODULE,                                   \
81                 .n_voltages = ARRAY_SIZE(ldo_volt_table),               \
82                 .volt_table = ldo_volt_table,                           \
83                 .vsel_reg = vosel,                                      \
84                 .vsel_mask = vosel_mask,                                \
85         },                                                              \
86 }
87
88 #define MT6331_LDO_S(match, vreg, ldo_volt_table, enreg, enbit, vosel,  \
89                      vosel_mask, _modeset_reg, _modeset_mask,           \
90                      _status_reg, _status_mask)                         \
91 [MT6331_ID_##vreg] = {                                                  \
92         .desc = {                                                       \
93                 .name = #vreg,                                          \
94                 .of_match = of_match_ptr(match),                        \
95                 .ops = &mt6331_volt_table_no_qi_ops,                    \
96                 .type = REGULATOR_VOLTAGE,                              \
97                 .id = MT6331_ID_##vreg,                                 \
98                 .owner = THIS_MODULE,                                   \
99                 .n_voltages = ARRAY_SIZE(ldo_volt_table),               \
100                 .volt_table = ldo_volt_table,                           \
101                 .vsel_reg = vosel,                                      \
102                 .vsel_mask = vosel_mask,                                \
103                 .enable_reg = enreg,                                    \
104                 .enable_mask = BIT(enbit),                              \
105         },                                                              \
106         .modeset_reg = _modeset_reg,                                    \
107         .modeset_mask = _modeset_mask,                                  \
108         .status_reg = _status_reg,                                      \
109         .status_mask = _status_mask,                                    \
110 }
111
112 #define MT6331_LDO(match, vreg, ldo_volt_table, enreg, enbit, vosel,    \
113                    vosel_mask, _modeset_reg, _modeset_mask)             \
114 [MT6331_ID_##vreg] = {                                                  \
115         .desc = {                                                       \
116                 .name = #vreg,                                          \
117                 .of_match = of_match_ptr(match),                        \
118                 .ops = (_modeset_reg ?                                  \
119                         &mt6331_volt_table_ops :                        \
120                         &mt6331_volt_table_no_ms_ops),                  \
121                 .type = REGULATOR_VOLTAGE,                              \
122                 .id = MT6331_ID_##vreg,                                 \
123                 .owner = THIS_MODULE,                                   \
124                 .n_voltages = ARRAY_SIZE(ldo_volt_table),               \
125                 .volt_table = ldo_volt_table,                           \
126                 .vsel_reg = vosel,                                      \
127                 .vsel_mask = vosel_mask,                                \
128                 .enable_reg = enreg,                                    \
129                 .enable_mask = BIT(enbit),                              \
130         },                                                              \
131         .qi = BIT(15),                                                  \
132         .modeset_reg = _modeset_reg,                                    \
133         .modeset_mask = _modeset_mask,                                  \
134 }
135
136 #define MT6331_REG_FIXED(match, vreg, enreg, enbit, qibit, volt,        \
137                          _modeset_reg, _modeset_mask)                   \
138 [MT6331_ID_##vreg] = {                                                  \
139         .desc = {                                                       \
140                 .name = #vreg,                                          \
141                 .of_match = of_match_ptr(match),                        \
142                 .ops = (_modeset_reg ?                                  \
143                         &mt6331_volt_fixed_ops :                        \
144                         &mt6331_volt_fixed_no_ms_ops),                  \
145                 .type = REGULATOR_VOLTAGE,                              \
146                 .id = MT6331_ID_##vreg,                                 \
147                 .owner = THIS_MODULE,                                   \
148                 .n_voltages = 1,                                        \
149                 .enable_reg = enreg,                                    \
150                 .enable_mask = BIT(enbit),                              \
151                 .min_uV = volt,                                         \
152         },                                                              \
153         .qi = BIT(qibit),                                               \
154         .modeset_reg = _modeset_reg,                                    \
155         .modeset_mask = _modeset_mask,                                  \
156 }
157
158 static const struct linear_range buck_volt_range[] = {
159         REGULATOR_LINEAR_RANGE(700000, 0, 0x7f, 6250),
160 };
161
162 static const unsigned int ldo_volt_table1[] = {
163         2800000, 3000000, 0, 3200000
164 };
165
166 static const unsigned int ldo_volt_table2[] = {
167         1500000, 1800000, 2500000, 2800000,
168 };
169
170 static const unsigned int ldo_volt_table3[] = {
171         1200000, 1300000, 1500000, 1800000, 2000000, 2800000, 3000000, 3300000,
172 };
173
174 static const unsigned int ldo_volt_table4[] = {
175         0, 0, 1700000, 1800000, 1860000, 2760000, 3000000, 3100000,
176 };
177
178 static const unsigned int ldo_volt_table5[] = {
179         1800000, 3300000, 1800000, 3300000,
180 };
181
182 static const unsigned int ldo_volt_table6[] = {
183         3000000, 3300000,
184 };
185
186 static const unsigned int ldo_volt_table7[] = {
187         1200000, 1600000, 1700000, 1800000, 1900000, 2000000, 2100000, 2200000,
188 };
189
190 static const unsigned int ldo_volt_table8[] = {
191         900000, 1000000, 1100000, 1220000, 1300000, 1500000, 1500000, 1500000,
192 };
193
194 static const unsigned int ldo_volt_table9[] = {
195         1000000, 1050000, 1100000, 1150000, 1200000, 1250000, 1300000, 1300000,
196 };
197
198 static const unsigned int ldo_volt_table10[] = {
199         1200000, 1300000, 1500000, 1800000,
200 };
201
202 static const unsigned int ldo_volt_table11[] = {
203         1200000, 1300000, 1400000, 1500000, 1600000, 1700000, 1800000, 1800000,
204 };
205
206 static int mt6331_get_status(struct regulator_dev *rdev)
207 {
208         struct mt6331_regulator_info *info = rdev_get_drvdata(rdev);
209         u32 regval;
210         int ret;
211
212         ret = regmap_read(rdev->regmap, info->desc.enable_reg, &regval);
213         if (ret != 0) {
214                 dev_err(&rdev->dev, "Failed to get enable reg: %d\n", ret);
215                 return ret;
216         }
217
218         return (regval & info->qi) ? REGULATOR_STATUS_ON : REGULATOR_STATUS_OFF;
219 }
220
221 static int mt6331_ldo_set_mode(struct regulator_dev *rdev, unsigned int mode)
222 {
223         struct mt6331_regulator_info *info = rdev_get_drvdata(rdev);
224         int val;
225
226         switch (mode) {
227         case REGULATOR_MODE_STANDBY:
228                 val = MT6331_LDO_MODE_LP;
229                 break;
230         case REGULATOR_MODE_NORMAL:
231                 val = MT6331_LDO_MODE_NORMAL;
232                 break;
233         default:
234                 return -EINVAL;
235         }
236
237         val <<= ffs(info->modeset_mask) - 1;
238
239         return regmap_update_bits(rdev->regmap, info->modeset_reg,
240                                   info->modeset_mask, val);
241 }
242
243 static unsigned int mt6331_ldo_get_mode(struct regulator_dev *rdev)
244 {
245         struct mt6331_regulator_info *info = rdev_get_drvdata(rdev);
246         unsigned int val;
247         int ret;
248
249         ret = regmap_read(rdev->regmap, info->modeset_reg, &val);
250         if (ret < 0)
251                 return ret;
252
253         val &= info->modeset_mask;
254         val >>= ffs(info->modeset_mask) - 1;
255
256         return (val & BIT(0)) ? REGULATOR_MODE_STANDBY : REGULATOR_MODE_NORMAL;
257 }
258
259 static const struct regulator_ops mt6331_volt_range_ops = {
260         .list_voltage = regulator_list_voltage_linear_range,
261         .map_voltage = regulator_map_voltage_linear_range,
262         .set_voltage_sel = regulator_set_voltage_sel_regmap,
263         .get_voltage_sel = regulator_get_voltage_sel_regmap,
264         .set_voltage_time_sel = regulator_set_voltage_time_sel,
265         .enable = regulator_enable_regmap,
266         .disable = regulator_disable_regmap,
267         .is_enabled = regulator_is_enabled_regmap,
268         .get_status = mt6331_get_status,
269 };
270
271 static const struct regulator_ops mt6331_volt_table_no_ms_ops = {
272         .list_voltage = regulator_list_voltage_table,
273         .map_voltage = regulator_map_voltage_iterate,
274         .set_voltage_sel = regulator_set_voltage_sel_regmap,
275         .get_voltage_sel = regulator_get_voltage_sel_regmap,
276         .set_voltage_time_sel = regulator_set_voltage_time_sel,
277         .enable = regulator_enable_regmap,
278         .disable = regulator_disable_regmap,
279         .is_enabled = regulator_is_enabled_regmap,
280         .get_status = mt6331_get_status,
281 };
282
283 static const struct regulator_ops mt6331_volt_table_no_qi_ops = {
284         .list_voltage = regulator_list_voltage_table,
285         .map_voltage = regulator_map_voltage_iterate,
286         .set_voltage_sel = regulator_set_voltage_sel_regmap,
287         .get_voltage_sel = regulator_get_voltage_sel_regmap,
288         .set_voltage_time_sel = regulator_set_voltage_time_sel,
289         .enable = regulator_enable_regmap,
290         .disable = regulator_disable_regmap,
291         .is_enabled = regulator_is_enabled_regmap,
292         .set_mode = mt6331_ldo_set_mode,
293         .get_mode = mt6331_ldo_get_mode,
294 };
295
296 static const struct regulator_ops mt6331_volt_table_ops = {
297         .list_voltage = regulator_list_voltage_table,
298         .map_voltage = regulator_map_voltage_iterate,
299         .set_voltage_sel = regulator_set_voltage_sel_regmap,
300         .get_voltage_sel = regulator_get_voltage_sel_regmap,
301         .set_voltage_time_sel = regulator_set_voltage_time_sel,
302         .enable = regulator_enable_regmap,
303         .disable = regulator_disable_regmap,
304         .is_enabled = regulator_is_enabled_regmap,
305         .get_status = mt6331_get_status,
306         .set_mode = mt6331_ldo_set_mode,
307         .get_mode = mt6331_ldo_get_mode,
308 };
309
310 static const struct regulator_ops mt6331_volt_table_ao_ops = {
311         .list_voltage = regulator_list_voltage_table,
312         .map_voltage = regulator_map_voltage_iterate,
313         .set_voltage_sel = regulator_set_voltage_sel_regmap,
314         .get_voltage_sel = regulator_get_voltage_sel_regmap,
315         .set_voltage_time_sel = regulator_set_voltage_time_sel,
316 };
317
318 static const struct regulator_ops mt6331_volt_fixed_no_ms_ops = {
319         .list_voltage = regulator_list_voltage_linear,
320         .enable = regulator_enable_regmap,
321         .disable = regulator_disable_regmap,
322         .is_enabled = regulator_is_enabled_regmap,
323         .get_status = mt6331_get_status,
324 };
325
326 static const struct regulator_ops mt6331_volt_fixed_ops = {
327         .list_voltage = regulator_list_voltage_linear,
328         .enable = regulator_enable_regmap,
329         .disable = regulator_disable_regmap,
330         .is_enabled = regulator_is_enabled_regmap,
331         .get_status = mt6331_get_status,
332         .set_mode = mt6331_ldo_set_mode,
333         .get_mode = mt6331_ldo_get_mode,
334 };
335
336 /* The array is indexed by id(MT6331_ID_XXX) */
337 static struct mt6331_regulator_info mt6331_regulators[] = {
338         MT6331_BUCK("buck-vdvfs11", VDVFS11, 700000, 1493750, 6250,
339                     buck_volt_range, MT6331_VDVFS11_CON9,
340                     MT6331_VDVFS11_CON11, GENMASK(6, 0),
341                     MT6331_VDVFS11_CON12, MT6331_VDVFS11_CON7),
342         MT6331_BUCK("buck-vdvfs12", VDVFS12, 700000, 1493750, 6250,
343                     buck_volt_range, MT6331_VDVFS12_CON9,
344                     MT6331_VDVFS12_CON11, GENMASK(6, 0),
345                     MT6331_VDVFS12_CON12, MT6331_VDVFS12_CON7),
346         MT6331_BUCK("buck-vdvfs13", VDVFS13, 700000, 1493750, 6250,
347                     buck_volt_range, MT6331_VDVFS13_CON9,
348                     MT6331_VDVFS13_CON11, GENMASK(6, 0),
349                     MT6331_VDVFS13_CON12, MT6331_VDVFS13_CON7),
350         MT6331_BUCK("buck-vdvfs14", VDVFS14, 700000, 1493750, 6250,
351                     buck_volt_range, MT6331_VDVFS14_CON9,
352                     MT6331_VDVFS14_CON11, GENMASK(6, 0),
353                     MT6331_VDVFS14_CON12, MT6331_VDVFS14_CON7),
354         MT6331_BUCK("buck-vcore2", VCORE2, 700000, 1493750, 6250,
355                     buck_volt_range, MT6331_VCORE2_CON9,
356                     MT6331_VCORE2_CON11, GENMASK(6, 0),
357                     MT6331_VCORE2_CON12, MT6331_VCORE2_CON7),
358         MT6331_REG_FIXED("buck-vio18", VIO18, MT6331_VIO18_CON9, 0, 13, 1800000, 0, 0),
359         MT6331_REG_FIXED("ldo-vrtc", VRTC, MT6331_DIGLDO_CON11, 8, 15, 2800000, 0, 0),
360         MT6331_REG_FIXED("ldo-vtcxo1", VTCXO1, MT6331_ANALDO_CON1, 10, 15, 2800000,
361                          MT6331_ANALDO_CON1, GENMASK(1, 0)),
362         MT6331_REG_FIXED("ldo-vtcxo2", VTCXO2, MT6331_ANALDO_CON2, 10, 15, 2800000,
363                          MT6331_ANALDO_CON2, GENMASK(1, 0)),
364         MT6331_REG_FIXED("ldo-vsram", VSRAM_DVFS1, MT6331_SYSLDO_CON4, 10, 15, 1012500,
365                          MT6331_SYSLDO_CON4, GENMASK(1, 0)),
366         MT6331_REG_FIXED("ldo-vio28", VIO28, MT6331_DIGLDO_CON1, 10, 15, 2800000,
367                          MT6331_DIGLDO_CON1, GENMASK(1, 0)),
368         MT6331_LDO("ldo-avdd32aud", AVDD32_AUD, ldo_volt_table1, MT6331_ANALDO_CON3, 10,
369                    MT6331_ANALDO_CON10, GENMASK(6, 5), MT6331_ANALDO_CON3, GENMASK(1, 0)),
370         MT6331_LDO("ldo-vauxa32", VAUXA32, ldo_volt_table1, MT6331_ANALDO_CON4, 10,
371                    MT6331_ANALDO_CON6, GENMASK(6, 5), MT6331_ANALDO_CON4, GENMASK(1, 0)),
372         MT6331_LDO("ldo-vemc33", VEMC33, ldo_volt_table6, MT6331_DIGLDO_CON5, 10,
373                    MT6331_DIGLDO_CON17, BIT(6), MT6331_DIGLDO_CON5, GENMASK(1, 0)),
374         MT6331_LDO("ldo-vibr", VIBR, ldo_volt_table3, MT6331_DIGLDO_CON12, 10,
375                    MT6331_DIGLDO_CON20, GENMASK(6, 4), MT6331_DIGLDO_CON12, GENMASK(1, 0)),
376         MT6331_LDO("ldo-vmc", VMC, ldo_volt_table5, MT6331_DIGLDO_CON3, 10,
377                    MT6331_DIGLDO_CON15, GENMASK(5, 4), MT6331_DIGLDO_CON3, GENMASK(1, 0)),
378         MT6331_LDO("ldo-vmch", VMCH, ldo_volt_table6, MT6331_DIGLDO_CON4, 10,
379                    MT6331_DIGLDO_CON16, BIT(6), MT6331_DIGLDO_CON4, GENMASK(1, 0)),
380         MT6331_LDO("ldo-vmipi", VMIPI, ldo_volt_table3, MT6331_SYSLDO_CON5, 10,
381                    MT6331_SYSLDO_CON13, GENMASK(5, 3), MT6331_SYSLDO_CON5, GENMASK(1, 0)),
382         MT6331_LDO("ldo-vsim1", VSIM1, ldo_volt_table4, MT6331_DIGLDO_CON8, 10,
383                    MT6331_DIGLDO_CON21, GENMASK(6, 4), MT6331_DIGLDO_CON8, GENMASK(1, 0)),
384         MT6331_LDO("ldo-vsim2", VSIM2, ldo_volt_table4, MT6331_DIGLDO_CON9, 10,
385                    MT6331_DIGLDO_CON22, GENMASK(6, 4), MT6331_DIGLDO_CON9, GENMASK(1, 0)),
386         MT6331_LDO("ldo-vusb10", VUSB10, ldo_volt_table9, MT6331_SYSLDO_CON2, 10,
387                    MT6331_SYSLDO_CON10, GENMASK(5, 3), MT6331_SYSLDO_CON2, GENMASK(1, 0)),
388         MT6331_LDO("ldo-vcama", VCAMA, ldo_volt_table2, MT6331_ANALDO_CON5, 15,
389                    MT6331_ANALDO_CON9, GENMASK(5, 4), 0, 0),
390         MT6331_LDO_S("ldo-vcamaf", VCAM_AF, ldo_volt_table3, MT6331_DIGLDO_CON2, 10,
391                      MT6331_DIGLDO_CON14, GENMASK(6, 4), MT6331_DIGLDO_CON2, GENMASK(1, 0),
392                      MT6331_EN_STATUS1, BIT(0)),
393         MT6331_LDO_S("ldo-vcamd", VCAMD, ldo_volt_table8, MT6331_SYSLDO_CON1, 15,
394                      MT6331_SYSLDO_CON9, GENMASK(6, 4), MT6331_SYSLDO_CON1, GENMASK(1, 0),
395                      MT6331_EN_STATUS1, BIT(11)),
396         MT6331_LDO_S("ldo-vcamio", VCAM_IO,  ldo_volt_table10, MT6331_SYSLDO_CON3, 10,
397                      MT6331_SYSLDO_CON11, GENMASK(4, 3), MT6331_SYSLDO_CON3, GENMASK(1, 0),
398                      MT6331_EN_STATUS1, BIT(13)),
399         MT6331_LDO_S("ldo-vgp1", VGP1, ldo_volt_table3, MT6331_DIGLDO_CON6, 10,
400                      MT6331_DIGLDO_CON19, GENMASK(6, 4), MT6331_DIGLDO_CON6, GENMASK(1, 0),
401                      MT6331_EN_STATUS1, BIT(4)),
402         MT6331_LDO_S("ldo-vgp2", VGP2, ldo_volt_table10, MT6331_SYSLDO_CON6, 10,
403                      MT6331_SYSLDO_CON14, GENMASK(4, 3), MT6331_SYSLDO_CON6, GENMASK(1, 0),
404                      MT6331_EN_STATUS1, BIT(15)),
405         MT6331_LDO_S("ldo-vgp3", VGP3, ldo_volt_table10, MT6331_SYSLDO_CON7, 10,
406                      MT6331_SYSLDO_CON15, GENMASK(4, 3), MT6331_SYSLDO_CON7, GENMASK(1, 0),
407                      MT6331_EN_STATUS2, BIT(0)),
408         MT6331_LDO_S("ldo-vgp4", VGP4, ldo_volt_table7, MT6331_DIGLDO_CON7, 10,
409                      MT6331_DIGLDO_CON18, GENMASK(6, 4), MT6331_DIGLDO_CON7, GENMASK(1, 0),
410                      MT6331_EN_STATUS1, BIT(5)),
411         MT6331_LDO_AO("ldo-vdig18", VDIG18, ldo_volt_table11,
412                       MT6331_DIGLDO_CON28, GENMASK(14, 12)),
413 };
414
415 static int mt6331_set_buck_vosel_reg(struct platform_device *pdev)
416 {
417         struct mt6397_chip *mt6331 = dev_get_drvdata(pdev->dev.parent);
418         int i;
419         u32 regval;
420
421         for (i = 0; i < MT6331_ID_VREG_MAX; i++) {
422                 if (mt6331_regulators[i].vselctrl_reg) {
423                         if (regmap_read(mt6331->regmap,
424                                 mt6331_regulators[i].vselctrl_reg,
425                                 &regval) < 0) {
426                                 dev_err(&pdev->dev,
427                                         "Failed to read buck ctrl\n");
428                                 return -EIO;
429                         }
430
431                         if (regval & mt6331_regulators[i].vselctrl_mask) {
432                                 mt6331_regulators[i].desc.vsel_reg =
433                                 mt6331_regulators[i].vselon_reg;
434                         }
435                 }
436         }
437
438         return 0;
439 }
440
441 static int mt6331_regulator_probe(struct platform_device *pdev)
442 {
443         struct mt6397_chip *mt6331 = dev_get_drvdata(pdev->dev.parent);
444         struct regulator_config config = {};
445         struct regulator_dev *rdev;
446         int i;
447         u32 reg_value;
448
449         /* Query buck controller to select activated voltage register part */
450         if (mt6331_set_buck_vosel_reg(pdev))
451                 return -EIO;
452
453         /* Read PMIC chip revision to update constraints and voltage table */
454         if (regmap_read(mt6331->regmap, MT6331_HWCID, &reg_value) < 0) {
455                 dev_err(&pdev->dev, "Failed to read Chip ID\n");
456                 return -EIO;
457         }
458         reg_value &= GENMASK(7, 0);
459
460         dev_info(&pdev->dev, "Chip ID = 0x%x\n", reg_value);
461
462         /*
463          * ChipID 0x10 is "MT6331 E1", has a different voltage table and
464          * it's currently not supported in this driver. Upon detection of
465          * this ID, refuse to register the regulators, as we will wrongly
466          * interpret the VSEL for this revision, potentially overvolting
467          * some device.
468          */
469         if (reg_value == 0x10) {
470                 dev_err(&pdev->dev, "Chip version not supported. Bailing out.\n");
471                 return -EINVAL;
472         }
473
474         for (i = 0; i < MT6331_ID_VREG_MAX; i++) {
475                 config.dev = &pdev->dev;
476                 config.driver_data = &mt6331_regulators[i];
477                 config.regmap = mt6331->regmap;
478                 rdev = devm_regulator_register(&pdev->dev,
479                                 &mt6331_regulators[i].desc, &config);
480                 if (IS_ERR(rdev)) {
481                         dev_err(&pdev->dev, "failed to register %s\n",
482                                 mt6331_regulators[i].desc.name);
483                         return PTR_ERR(rdev);
484                 }
485         }
486         return 0;
487 }
488
489 static const struct platform_device_id mt6331_platform_ids[] = {
490         {"mt6331-regulator", 0},
491         { /* sentinel */ },
492 };
493 MODULE_DEVICE_TABLE(platform, mt6331_platform_ids);
494
495 static struct platform_driver mt6331_regulator_driver = {
496         .driver = {
497                 .name = "mt6331-regulator",
498                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
499         },
500         .probe = mt6331_regulator_probe,
501         .id_table = mt6331_platform_ids,
502 };
503
504 module_platform_driver(mt6331_regulator_driver);
505
506 MODULE_AUTHOR("AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>");
507 MODULE_DESCRIPTION("Regulator Driver for MediaTek MT6331 PMIC");
508 MODULE_LICENSE("GPL");