2 * max8660.c -- Voltage regulation for the Maxim 8660/8661
4 * based on max1586.c and wm8400-regulator.c
6 * Copyright (C) 2009 Wolfram Sang, Pengutronix e.K.
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the Free
10 * Software Foundation; version 2 of the License.
12 * This program is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
17 * You should have received a copy of the GNU General Public License along with
18 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
19 * Place, Suite 330, Boston, MA 02111-1307 USA
23 * Datasheet: http://datasheets.maxim-ic.com/en/ds/MAX8660-MAX8661.pdf
25 * This chip is a bit nasty because it is a write-only device. Thus, the driver
26 * uses shadow registers to keep track of its values. The main problem appears
27 * to be the initialization: When Linux boots up, we cannot know if the chip is
28 * in the default state or not, so we would have to pass such information in
29 * platform_data. As this adds a bit of complexity to the driver, this is left
30 * out for now until it is really needed.
32 * [A|S|M]DTV1 registers are currently not used, but [A|S|M]DTV2.
34 * If the driver is feature complete, it might be worth to check if one set of
35 * functions for V3-V7 is sufficient. For maximum flexibility during
36 * development, they are separated for now.
40 #include <linux/module.h>
41 #include <linux/err.h>
42 #include <linux/i2c.h>
43 #include <linux/platform_device.h>
44 #include <linux/regulator/driver.h>
45 #include <linux/slab.h>
46 #include <linux/regulator/max8660.h>
48 #include <linux/of_device.h>
49 #include <linux/regulator/of_regulator.h>
51 #define MAX8660_DCDC_MIN_UV 725000
52 #define MAX8660_DCDC_MAX_UV 1800000
53 #define MAX8660_DCDC_STEP 25000
54 #define MAX8660_DCDC_MAX_SEL 0x2b
56 #define MAX8660_LDO5_MIN_UV 1700000
57 #define MAX8660_LDO5_MAX_UV 2000000
58 #define MAX8660_LDO5_STEP 25000
59 #define MAX8660_LDO5_MAX_SEL 0x0c
61 #define MAX8660_LDO67_MIN_UV 1800000
62 #define MAX8660_LDO67_MAX_UV 3300000
63 #define MAX8660_LDO67_STEP 100000
64 #define MAX8660_LDO67_MAX_SEL 0x0f
78 MAX8660_N_REGS, /* not a real register */
82 struct i2c_client *client;
83 u8 shadow_regs[MAX8660_N_REGS]; /* as chip is write only */
86 static int max8660_write(struct max8660 *max8660, u8 reg, u8 mask, u8 val)
88 static const u8 max8660_addresses[MAX8660_N_REGS] =
89 { 0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80 };
92 u8 reg_val = (max8660->shadow_regs[reg] & mask) | val;
93 dev_vdbg(&max8660->client->dev, "Writing reg %02x with %02x\n",
94 max8660_addresses[reg], reg_val);
96 ret = i2c_smbus_write_byte_data(max8660->client,
97 max8660_addresses[reg], reg_val);
99 max8660->shadow_regs[reg] = reg_val;
109 static int max8660_dcdc_is_enabled(struct regulator_dev *rdev)
111 struct max8660 *max8660 = rdev_get_drvdata(rdev);
112 u8 val = max8660->shadow_regs[MAX8660_OVER1];
113 u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
114 return !!(val & mask);
117 static int max8660_dcdc_enable(struct regulator_dev *rdev)
119 struct max8660 *max8660 = rdev_get_drvdata(rdev);
120 u8 bit = (rdev_get_id(rdev) == MAX8660_V3) ? 1 : 4;
121 return max8660_write(max8660, MAX8660_OVER1, 0xff, bit);
124 static int max8660_dcdc_disable(struct regulator_dev *rdev)
126 struct max8660 *max8660 = rdev_get_drvdata(rdev);
127 u8 mask = (rdev_get_id(rdev) == MAX8660_V3) ? ~1 : ~4;
128 return max8660_write(max8660, MAX8660_OVER1, mask, 0);
131 static int max8660_dcdc_get_voltage_sel(struct regulator_dev *rdev)
133 struct max8660 *max8660 = rdev_get_drvdata(rdev);
135 u8 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
136 u8 selector = max8660->shadow_regs[reg];
140 static int max8660_dcdc_set_voltage_sel(struct regulator_dev *rdev,
141 unsigned int selector)
143 struct max8660 *max8660 = rdev_get_drvdata(rdev);
147 reg = (rdev_get_id(rdev) == MAX8660_V3) ? MAX8660_ADTV2 : MAX8660_SDTV2;
148 ret = max8660_write(max8660, reg, 0, selector);
152 /* Select target voltage register and activate regulation */
153 bits = (rdev_get_id(rdev) == MAX8660_V3) ? 0x03 : 0x30;
154 return max8660_write(max8660, MAX8660_VCC1, 0xff, bits);
157 static struct regulator_ops max8660_dcdc_ops = {
158 .is_enabled = max8660_dcdc_is_enabled,
159 .list_voltage = regulator_list_voltage_linear,
160 .map_voltage = regulator_map_voltage_linear,
161 .set_voltage_sel = max8660_dcdc_set_voltage_sel,
162 .get_voltage_sel = max8660_dcdc_get_voltage_sel,
170 static int max8660_ldo5_get_voltage_sel(struct regulator_dev *rdev)
172 struct max8660 *max8660 = rdev_get_drvdata(rdev);
174 u8 selector = max8660->shadow_regs[MAX8660_MDTV2];
178 static int max8660_ldo5_set_voltage_sel(struct regulator_dev *rdev,
179 unsigned int selector)
181 struct max8660 *max8660 = rdev_get_drvdata(rdev);
184 ret = max8660_write(max8660, MAX8660_MDTV2, 0, selector);
188 /* Select target voltage register and activate regulation */
189 return max8660_write(max8660, MAX8660_VCC1, 0xff, 0xc0);
192 static struct regulator_ops max8660_ldo5_ops = {
193 .list_voltage = regulator_list_voltage_linear,
194 .map_voltage = regulator_map_voltage_linear,
195 .set_voltage_sel = max8660_ldo5_set_voltage_sel,
196 .get_voltage_sel = max8660_ldo5_get_voltage_sel,
204 static int max8660_ldo67_is_enabled(struct regulator_dev *rdev)
206 struct max8660 *max8660 = rdev_get_drvdata(rdev);
207 u8 val = max8660->shadow_regs[MAX8660_OVER2];
208 u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
209 return !!(val & mask);
212 static int max8660_ldo67_enable(struct regulator_dev *rdev)
214 struct max8660 *max8660 = rdev_get_drvdata(rdev);
215 u8 bit = (rdev_get_id(rdev) == MAX8660_V6) ? 2 : 4;
216 return max8660_write(max8660, MAX8660_OVER2, 0xff, bit);
219 static int max8660_ldo67_disable(struct regulator_dev *rdev)
221 struct max8660 *max8660 = rdev_get_drvdata(rdev);
222 u8 mask = (rdev_get_id(rdev) == MAX8660_V6) ? ~2 : ~4;
223 return max8660_write(max8660, MAX8660_OVER2, mask, 0);
226 static int max8660_ldo67_get_voltage_sel(struct regulator_dev *rdev)
228 struct max8660 *max8660 = rdev_get_drvdata(rdev);
230 u8 shift = (rdev_get_id(rdev) == MAX8660_V6) ? 0 : 4;
231 u8 selector = (max8660->shadow_regs[MAX8660_L12VCR] >> shift) & 0xf;
235 static int max8660_ldo67_set_voltage_sel(struct regulator_dev *rdev,
236 unsigned int selector)
238 struct max8660 *max8660 = rdev_get_drvdata(rdev);
240 if (rdev_get_id(rdev) == MAX8660_V6)
241 return max8660_write(max8660, MAX8660_L12VCR, 0xf0, selector);
243 return max8660_write(max8660, MAX8660_L12VCR, 0x0f,
247 static struct regulator_ops max8660_ldo67_ops = {
248 .is_enabled = max8660_ldo67_is_enabled,
249 .enable = max8660_ldo67_enable,
250 .disable = max8660_ldo67_disable,
251 .list_voltage = regulator_list_voltage_linear,
252 .map_voltage = regulator_map_voltage_linear,
253 .get_voltage_sel = max8660_ldo67_get_voltage_sel,
254 .set_voltage_sel = max8660_ldo67_set_voltage_sel,
257 static const struct regulator_desc max8660_reg[] = {
261 .ops = &max8660_dcdc_ops,
262 .type = REGULATOR_VOLTAGE,
263 .n_voltages = MAX8660_DCDC_MAX_SEL + 1,
264 .owner = THIS_MODULE,
265 .min_uV = MAX8660_DCDC_MIN_UV,
266 .uV_step = MAX8660_DCDC_STEP,
271 .ops = &max8660_dcdc_ops,
272 .type = REGULATOR_VOLTAGE,
273 .n_voltages = MAX8660_DCDC_MAX_SEL + 1,
274 .owner = THIS_MODULE,
275 .min_uV = MAX8660_DCDC_MIN_UV,
276 .uV_step = MAX8660_DCDC_STEP,
281 .ops = &max8660_ldo5_ops,
282 .type = REGULATOR_VOLTAGE,
283 .n_voltages = MAX8660_LDO5_MAX_SEL + 1,
284 .owner = THIS_MODULE,
285 .min_uV = MAX8660_LDO5_MIN_UV,
286 .uV_step = MAX8660_LDO5_STEP,
291 .ops = &max8660_ldo67_ops,
292 .type = REGULATOR_VOLTAGE,
293 .n_voltages = MAX8660_LDO67_MAX_SEL + 1,
294 .owner = THIS_MODULE,
295 .min_uV = MAX8660_LDO67_MIN_UV,
296 .uV_step = MAX8660_LDO67_STEP,
301 .ops = &max8660_ldo67_ops,
302 .type = REGULATOR_VOLTAGE,
303 .n_voltages = MAX8660_LDO67_MAX_SEL + 1,
304 .owner = THIS_MODULE,
305 .min_uV = MAX8660_LDO67_MIN_UV,
306 .uV_step = MAX8660_LDO67_STEP,
316 static const struct of_device_id max8660_dt_ids[] = {
317 { .compatible = "maxim,max8660", .data = (void *) MAX8660 },
318 { .compatible = "maxim,max8661", .data = (void *) MAX8661 },
321 MODULE_DEVICE_TABLE(of, max8660_dt_ids);
323 static int max8660_pdata_from_dt(struct device *dev,
324 struct device_node **of_node,
325 struct max8660_platform_data *pdata)
328 struct device_node *np;
329 struct max8660_subdev_data *sub;
330 struct of_regulator_match rmatch[ARRAY_SIZE(max8660_reg)];
332 np = of_get_child_by_name(dev->of_node, "regulators");
334 dev_err(dev, "missing 'regulators' subnode in DT\n");
338 for (i = 0; i < ARRAY_SIZE(rmatch); i++)
339 rmatch[i].name = max8660_reg[i].name;
341 matched = of_regulator_match(dev, np, rmatch, ARRAY_SIZE(rmatch));
346 pdata->subdevs = devm_kzalloc(dev, sizeof(struct max8660_subdev_data) *
347 matched, GFP_KERNEL);
351 pdata->num_subdevs = matched;
352 sub = pdata->subdevs;
354 for (i = 0; i < matched; i++) {
356 sub->name = rmatch[i].name;
357 sub->platform_data = rmatch[i].init_data;
358 of_node[i] = rmatch[i].of_node;
365 static inline int max8660_pdata_from_dt(struct device *dev,
366 struct device_node **of_node,
367 struct max8660_platform_data *pdata)
373 static int max8660_probe(struct i2c_client *client,
374 const struct i2c_device_id *i2c_id)
376 struct device *dev = &client->dev;
377 struct max8660_platform_data *pdata = dev_get_platdata(dev);
378 struct regulator_config config = { };
379 struct max8660 *max8660;
380 int boot_on, i, id, ret = -EINVAL;
381 struct device_node *of_node[MAX8660_V_END];
384 if (dev->of_node && !pdata) {
385 const struct of_device_id *id;
386 struct max8660_platform_data pdata_of;
388 id = of_match_device(of_match_ptr(max8660_dt_ids), dev);
392 ret = max8660_pdata_from_dt(dev, of_node, &pdata_of);
397 type = (unsigned long) id->data;
399 type = i2c_id->driver_data;
400 memset(of_node, 0, sizeof(of_node));
403 if (pdata->num_subdevs > MAX8660_V_END) {
404 dev_err(dev, "Too many regulators found!\n");
408 max8660 = devm_kzalloc(dev, sizeof(struct max8660), GFP_KERNEL);
412 max8660->client = client;
414 if (pdata->en34_is_high) {
415 /* Simulate always on */
416 max8660->shadow_regs[MAX8660_OVER1] = 5;
418 /* Otherwise devices can be toggled via software */
419 max8660_dcdc_ops.enable = max8660_dcdc_enable;
420 max8660_dcdc_ops.disable = max8660_dcdc_disable;
424 * First, set up shadow registers to prevent glitches. As some
425 * registers are shared between regulators, everything must be properly
426 * set up for all regulators in advance.
428 max8660->shadow_regs[MAX8660_ADTV1] =
429 max8660->shadow_regs[MAX8660_ADTV2] =
430 max8660->shadow_regs[MAX8660_SDTV1] =
431 max8660->shadow_regs[MAX8660_SDTV2] = 0x1b;
432 max8660->shadow_regs[MAX8660_MDTV1] =
433 max8660->shadow_regs[MAX8660_MDTV2] = 0x04;
435 for (i = 0; i < pdata->num_subdevs; i++) {
437 if (!pdata->subdevs[i].platform_data)
440 boot_on = pdata->subdevs[i].platform_data->constraints.boot_on;
442 switch (pdata->subdevs[i].id) {
445 max8660->shadow_regs[MAX8660_OVER1] |= 1;
450 max8660->shadow_regs[MAX8660_OVER1] |= 4;
458 max8660->shadow_regs[MAX8660_OVER2] |= 2;
462 if (type == MAX8661) {
463 dev_err(dev, "Regulator not on this chip!\n");
468 max8660->shadow_regs[MAX8660_OVER2] |= 4;
472 dev_err(dev, "invalid regulator %s\n",
473 pdata->subdevs[i].name);
478 /* Finally register devices */
479 for (i = 0; i < pdata->num_subdevs; i++) {
480 struct regulator_dev *rdev;
482 id = pdata->subdevs[i].id;
485 config.init_data = pdata->subdevs[i].platform_data;
486 config.of_node = of_node[i];
487 config.driver_data = max8660;
489 rdev = devm_regulator_register(&client->dev,
490 &max8660_reg[id], &config);
493 dev_err(&client->dev, "failed to register %s\n",
494 max8660_reg[id].name);
495 return PTR_ERR(rdev);
499 i2c_set_clientdata(client, max8660);
503 static const struct i2c_device_id max8660_id[] = {
504 { .name = "max8660", .driver_data = MAX8660 },
505 { .name = "max8661", .driver_data = MAX8661 },
508 MODULE_DEVICE_TABLE(i2c, max8660_id);
510 static struct i2c_driver max8660_driver = {
511 .probe = max8660_probe,
514 .owner = THIS_MODULE,
516 .id_table = max8660_id,
519 static int __init max8660_init(void)
521 return i2c_add_driver(&max8660_driver);
523 subsys_initcall(max8660_init);
525 static void __exit max8660_exit(void)
527 i2c_del_driver(&max8660_driver);
529 module_exit(max8660_exit);
531 /* Module information */
532 MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
533 MODULE_AUTHOR("Wolfram Sang");
534 MODULE_LICENSE("GPL v2");