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 */
84 struct regulator_dev
*rdev
[];
87 static int max8660_write(struct max8660
*max8660
, u8 reg
, u8 mask
, u8 val
)
89 static const u8 max8660_addresses
[MAX8660_N_REGS
] =
90 { 0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80 };
93 u8 reg_val
= (max8660
->shadow_regs
[reg
] & mask
) | val
;
94 dev_vdbg(&max8660
->client
->dev
, "Writing reg %02x with %02x\n",
95 max8660_addresses
[reg
], reg_val
);
97 ret
= i2c_smbus_write_byte_data(max8660
->client
,
98 max8660_addresses
[reg
], reg_val
);
100 max8660
->shadow_regs
[reg
] = reg_val
;
110 static int max8660_dcdc_is_enabled(struct regulator_dev
*rdev
)
112 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
113 u8 val
= max8660
->shadow_regs
[MAX8660_OVER1
];
114 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V3
) ? 1 : 4;
115 return !!(val
& mask
);
118 static int max8660_dcdc_enable(struct regulator_dev
*rdev
)
120 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
121 u8 bit
= (rdev_get_id(rdev
) == MAX8660_V3
) ? 1 : 4;
122 return max8660_write(max8660
, MAX8660_OVER1
, 0xff, bit
);
125 static int max8660_dcdc_disable(struct regulator_dev
*rdev
)
127 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
128 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V3
) ? ~1 : ~4;
129 return max8660_write(max8660
, MAX8660_OVER1
, mask
, 0);
132 static int max8660_dcdc_get_voltage_sel(struct regulator_dev
*rdev
)
134 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
136 u8 reg
= (rdev_get_id(rdev
) == MAX8660_V3
) ? MAX8660_ADTV2
: MAX8660_SDTV2
;
137 u8 selector
= max8660
->shadow_regs
[reg
];
141 static int max8660_dcdc_set_voltage_sel(struct regulator_dev
*rdev
,
142 unsigned int selector
)
144 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
148 reg
= (rdev_get_id(rdev
) == MAX8660_V3
) ? MAX8660_ADTV2
: MAX8660_SDTV2
;
149 ret
= max8660_write(max8660
, reg
, 0, selector
);
153 /* Select target voltage register and activate regulation */
154 bits
= (rdev_get_id(rdev
) == MAX8660_V3
) ? 0x03 : 0x30;
155 return max8660_write(max8660
, MAX8660_VCC1
, 0xff, bits
);
158 static struct regulator_ops max8660_dcdc_ops
= {
159 .is_enabled
= max8660_dcdc_is_enabled
,
160 .list_voltage
= regulator_list_voltage_linear
,
161 .map_voltage
= regulator_map_voltage_linear
,
162 .set_voltage_sel
= max8660_dcdc_set_voltage_sel
,
163 .get_voltage_sel
= max8660_dcdc_get_voltage_sel
,
171 static int max8660_ldo5_get_voltage_sel(struct regulator_dev
*rdev
)
173 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
175 u8 selector
= max8660
->shadow_regs
[MAX8660_MDTV2
];
179 static int max8660_ldo5_set_voltage_sel(struct regulator_dev
*rdev
,
180 unsigned int selector
)
182 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
185 ret
= max8660_write(max8660
, MAX8660_MDTV2
, 0, selector
);
189 /* Select target voltage register and activate regulation */
190 return max8660_write(max8660
, MAX8660_VCC1
, 0xff, 0xc0);
193 static struct regulator_ops max8660_ldo5_ops
= {
194 .list_voltage
= regulator_list_voltage_linear
,
195 .map_voltage
= regulator_map_voltage_linear
,
196 .set_voltage_sel
= max8660_ldo5_set_voltage_sel
,
197 .get_voltage_sel
= max8660_ldo5_get_voltage_sel
,
205 static int max8660_ldo67_is_enabled(struct regulator_dev
*rdev
)
207 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
208 u8 val
= max8660
->shadow_regs
[MAX8660_OVER2
];
209 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V6
) ? 2 : 4;
210 return !!(val
& mask
);
213 static int max8660_ldo67_enable(struct regulator_dev
*rdev
)
215 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
216 u8 bit
= (rdev_get_id(rdev
) == MAX8660_V6
) ? 2 : 4;
217 return max8660_write(max8660
, MAX8660_OVER2
, 0xff, bit
);
220 static int max8660_ldo67_disable(struct regulator_dev
*rdev
)
222 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
223 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V6
) ? ~2 : ~4;
224 return max8660_write(max8660
, MAX8660_OVER2
, mask
, 0);
227 static int max8660_ldo67_get_voltage_sel(struct regulator_dev
*rdev
)
229 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
231 u8 shift
= (rdev_get_id(rdev
) == MAX8660_V6
) ? 0 : 4;
232 u8 selector
= (max8660
->shadow_regs
[MAX8660_L12VCR
] >> shift
) & 0xf;
236 static int max8660_ldo67_set_voltage_sel(struct regulator_dev
*rdev
,
237 unsigned int selector
)
239 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
241 if (rdev_get_id(rdev
) == MAX8660_V6
)
242 return max8660_write(max8660
, MAX8660_L12VCR
, 0xf0, selector
);
244 return max8660_write(max8660
, MAX8660_L12VCR
, 0x0f,
248 static struct regulator_ops max8660_ldo67_ops
= {
249 .is_enabled
= max8660_ldo67_is_enabled
,
250 .enable
= max8660_ldo67_enable
,
251 .disable
= max8660_ldo67_disable
,
252 .list_voltage
= regulator_list_voltage_linear
,
253 .map_voltage
= regulator_map_voltage_linear
,
254 .get_voltage_sel
= max8660_ldo67_get_voltage_sel
,
255 .set_voltage_sel
= max8660_ldo67_set_voltage_sel
,
258 static const struct regulator_desc max8660_reg
[] = {
262 .ops
= &max8660_dcdc_ops
,
263 .type
= REGULATOR_VOLTAGE
,
264 .n_voltages
= MAX8660_DCDC_MAX_SEL
+ 1,
265 .owner
= THIS_MODULE
,
266 .min_uV
= MAX8660_DCDC_MIN_UV
,
267 .uV_step
= MAX8660_DCDC_STEP
,
272 .ops
= &max8660_dcdc_ops
,
273 .type
= REGULATOR_VOLTAGE
,
274 .n_voltages
= MAX8660_DCDC_MAX_SEL
+ 1,
275 .owner
= THIS_MODULE
,
276 .min_uV
= MAX8660_DCDC_MIN_UV
,
277 .uV_step
= MAX8660_DCDC_STEP
,
282 .ops
= &max8660_ldo5_ops
,
283 .type
= REGULATOR_VOLTAGE
,
284 .n_voltages
= MAX8660_LDO5_MAX_SEL
+ 1,
285 .owner
= THIS_MODULE
,
286 .min_uV
= MAX8660_LDO5_MIN_UV
,
287 .uV_step
= MAX8660_LDO5_STEP
,
292 .ops
= &max8660_ldo67_ops
,
293 .type
= REGULATOR_VOLTAGE
,
294 .n_voltages
= MAX8660_LDO67_MAX_SEL
+ 1,
295 .owner
= THIS_MODULE
,
296 .min_uV
= MAX8660_LDO67_MIN_UV
,
297 .uV_step
= MAX8660_LDO67_STEP
,
302 .ops
= &max8660_ldo67_ops
,
303 .type
= REGULATOR_VOLTAGE
,
304 .n_voltages
= MAX8660_LDO67_MAX_SEL
+ 1,
305 .owner
= THIS_MODULE
,
306 .min_uV
= MAX8660_LDO67_MIN_UV
,
307 .uV_step
= MAX8660_LDO67_STEP
,
317 static const struct of_device_id max8660_dt_ids
[] = {
318 { .compatible
= "maxim,max8660", .data
= (void *) MAX8660
},
319 { .compatible
= "maxim,max8661", .data
= (void *) MAX8661
},
322 MODULE_DEVICE_TABLE(of
, max8660_dt_ids
);
324 static int max8660_pdata_from_dt(struct device
*dev
,
325 struct device_node
**of_node
,
326 struct max8660_platform_data
*pdata
)
329 struct device_node
*np
;
330 struct max8660_subdev_data
*sub
;
331 struct of_regulator_match rmatch
[ARRAY_SIZE(max8660_reg
)];
333 np
= of_find_node_by_name(dev
->of_node
, "regulators");
335 dev_err(dev
, "missing 'regulators' subnode in DT\n");
339 for (i
= 0; i
< ARRAY_SIZE(rmatch
); i
++)
340 rmatch
[i
].name
= max8660_reg
[i
].name
;
342 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 regulator_dev
**rdev
;
377 struct device
*dev
= &client
->dev
;
378 struct max8660_platform_data
*pdata
= dev_get_platdata(dev
);
379 struct regulator_config config
= { };
380 struct max8660
*max8660
;
381 int boot_on
, i
, id
, ret
= -EINVAL
;
382 struct device_node
*of_node
[MAX8660_V_END
];
385 if (dev
->of_node
&& !pdata
) {
386 const struct of_device_id
*id
;
387 struct max8660_platform_data pdata_of
;
389 id
= of_match_device(of_match_ptr(max8660_dt_ids
), dev
);
393 ret
= max8660_pdata_from_dt(dev
, of_node
, &pdata_of
);
398 type
= (unsigned long) id
->data
;
400 type
= i2c_id
->driver_data
;
401 memset(of_node
, 0, sizeof(of_node
));
404 if (pdata
->num_subdevs
> MAX8660_V_END
) {
405 dev_err(dev
, "Too many regulators found!\n");
409 max8660
= devm_kzalloc(dev
, sizeof(struct max8660
) +
410 sizeof(struct regulator_dev
*) * MAX8660_V_END
,
415 max8660
->client
= client
;
416 rdev
= max8660
->rdev
;
418 if (pdata
->en34_is_high
) {
419 /* Simulate always on */
420 max8660
->shadow_regs
[MAX8660_OVER1
] = 5;
422 /* Otherwise devices can be toggled via software */
423 max8660_dcdc_ops
.enable
= max8660_dcdc_enable
;
424 max8660_dcdc_ops
.disable
= max8660_dcdc_disable
;
428 * First, set up shadow registers to prevent glitches. As some
429 * registers are shared between regulators, everything must be properly
430 * set up for all regulators in advance.
432 max8660
->shadow_regs
[MAX8660_ADTV1
] =
433 max8660
->shadow_regs
[MAX8660_ADTV2
] =
434 max8660
->shadow_regs
[MAX8660_SDTV1
] =
435 max8660
->shadow_regs
[MAX8660_SDTV2
] = 0x1b;
436 max8660
->shadow_regs
[MAX8660_MDTV1
] =
437 max8660
->shadow_regs
[MAX8660_MDTV2
] = 0x04;
439 for (i
= 0; i
< pdata
->num_subdevs
; i
++) {
441 if (!pdata
->subdevs
[i
].platform_data
)
444 boot_on
= pdata
->subdevs
[i
].platform_data
->constraints
.boot_on
;
446 switch (pdata
->subdevs
[i
].id
) {
449 max8660
->shadow_regs
[MAX8660_OVER1
] |= 1;
454 max8660
->shadow_regs
[MAX8660_OVER1
] |= 4;
462 max8660
->shadow_regs
[MAX8660_OVER2
] |= 2;
466 if (type
== MAX8661
) {
467 dev_err(dev
, "Regulator not on this chip!\n");
472 max8660
->shadow_regs
[MAX8660_OVER2
] |= 4;
476 dev_err(dev
, "invalid regulator %s\n",
477 pdata
->subdevs
[i
].name
);
482 /* Finally register devices */
483 for (i
= 0; i
< pdata
->num_subdevs
; i
++) {
485 id
= pdata
->subdevs
[i
].id
;
488 config
.init_data
= pdata
->subdevs
[i
].platform_data
;
489 config
.of_node
= of_node
[i
];
490 config
.driver_data
= max8660
;
492 rdev
[i
] = devm_regulator_register(&client
->dev
,
493 &max8660_reg
[id
], &config
);
494 if (IS_ERR(rdev
[i
])) {
495 ret
= PTR_ERR(rdev
[i
]);
496 dev_err(&client
->dev
, "failed to register %s\n",
497 max8660_reg
[id
].name
);
498 return PTR_ERR(rdev
[i
]);
502 i2c_set_clientdata(client
, max8660
);
506 static const struct i2c_device_id max8660_id
[] = {
507 { .name
= "max8660", .driver_data
= MAX8660
},
508 { .name
= "max8661", .driver_data
= MAX8661
},
511 MODULE_DEVICE_TABLE(i2c
, max8660_id
);
513 static struct i2c_driver max8660_driver
= {
514 .probe
= max8660_probe
,
517 .owner
= THIS_MODULE
,
519 .id_table
= max8660_id
,
522 static int __init
max8660_init(void)
524 return i2c_add_driver(&max8660_driver
);
526 subsys_initcall(max8660_init
);
528 static void __exit
max8660_exit(void)
530 i2c_del_driver(&max8660_driver
);
532 module_exit(max8660_exit
);
534 /* Module information */
535 MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
536 MODULE_AUTHOR("Wolfram Sang");
537 MODULE_LICENSE("GPL v2");