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 #define MAX8660_DCDC_MIN_UV 725000
49 #define MAX8660_DCDC_MAX_UV 1800000
50 #define MAX8660_DCDC_STEP 25000
51 #define MAX8660_DCDC_MAX_SEL 0x2b
53 #define MAX8660_LDO5_MIN_UV 1700000
54 #define MAX8660_LDO5_MAX_UV 2000000
55 #define MAX8660_LDO5_STEP 25000
56 #define MAX8660_LDO5_MAX_SEL 0x0c
58 #define MAX8660_LDO67_MIN_UV 1800000
59 #define MAX8660_LDO67_MAX_UV 3300000
60 #define MAX8660_LDO67_STEP 100000
61 #define MAX8660_LDO67_MAX_SEL 0x0f
75 MAX8660_N_REGS
, /* not a real register */
79 struct i2c_client
*client
;
80 u8 shadow_regs
[MAX8660_N_REGS
]; /* as chip is write only */
81 struct regulator_dev
*rdev
[];
84 static int max8660_write(struct max8660
*max8660
, u8 reg
, u8 mask
, u8 val
)
86 static const u8 max8660_addresses
[MAX8660_N_REGS
] =
87 { 0x10, 0x12, 0x20, 0x23, 0x24, 0x29, 0x2a, 0x32, 0x33, 0x39, 0x80 };
90 u8 reg_val
= (max8660
->shadow_regs
[reg
] & mask
) | val
;
91 dev_vdbg(&max8660
->client
->dev
, "Writing reg %02x with %02x\n",
92 max8660_addresses
[reg
], reg_val
);
94 ret
= i2c_smbus_write_byte_data(max8660
->client
,
95 max8660_addresses
[reg
], reg_val
);
97 max8660
->shadow_regs
[reg
] = reg_val
;
107 static int max8660_dcdc_is_enabled(struct regulator_dev
*rdev
)
109 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
110 u8 val
= max8660
->shadow_regs
[MAX8660_OVER1
];
111 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V3
) ? 1 : 4;
112 return !!(val
& mask
);
115 static int max8660_dcdc_enable(struct regulator_dev
*rdev
)
117 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
118 u8 bit
= (rdev_get_id(rdev
) == MAX8660_V3
) ? 1 : 4;
119 return max8660_write(max8660
, MAX8660_OVER1
, 0xff, bit
);
122 static int max8660_dcdc_disable(struct regulator_dev
*rdev
)
124 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
125 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V3
) ? ~1 : ~4;
126 return max8660_write(max8660
, MAX8660_OVER1
, mask
, 0);
129 static int max8660_dcdc_get_voltage_sel(struct regulator_dev
*rdev
)
131 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
133 u8 reg
= (rdev_get_id(rdev
) == MAX8660_V3
) ? MAX8660_ADTV2
: MAX8660_SDTV2
;
134 u8 selector
= max8660
->shadow_regs
[reg
];
138 static int max8660_dcdc_set_voltage_sel(struct regulator_dev
*rdev
,
139 unsigned int selector
)
141 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
145 reg
= (rdev_get_id(rdev
) == MAX8660_V3
) ? MAX8660_ADTV2
: MAX8660_SDTV2
;
146 ret
= max8660_write(max8660
, reg
, 0, selector
);
150 /* Select target voltage register and activate regulation */
151 bits
= (rdev_get_id(rdev
) == MAX8660_V3
) ? 0x03 : 0x30;
152 return max8660_write(max8660
, MAX8660_VCC1
, 0xff, bits
);
155 static struct regulator_ops max8660_dcdc_ops
= {
156 .is_enabled
= max8660_dcdc_is_enabled
,
157 .list_voltage
= regulator_list_voltage_linear
,
158 .map_voltage
= regulator_map_voltage_linear
,
159 .set_voltage_sel
= max8660_dcdc_set_voltage_sel
,
160 .get_voltage_sel
= max8660_dcdc_get_voltage_sel
,
168 static int max8660_ldo5_get_voltage_sel(struct regulator_dev
*rdev
)
170 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
172 u8 selector
= max8660
->shadow_regs
[MAX8660_MDTV2
];
176 static int max8660_ldo5_set_voltage_sel(struct regulator_dev
*rdev
,
177 unsigned int selector
)
179 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
182 ret
= max8660_write(max8660
, MAX8660_MDTV2
, 0, selector
);
186 /* Select target voltage register and activate regulation */
187 return max8660_write(max8660
, MAX8660_VCC1
, 0xff, 0xc0);
190 static struct regulator_ops max8660_ldo5_ops
= {
191 .list_voltage
= regulator_list_voltage_linear
,
192 .map_voltage
= regulator_map_voltage_linear
,
193 .set_voltage_sel
= max8660_ldo5_set_voltage_sel
,
194 .get_voltage_sel
= max8660_ldo5_get_voltage_sel
,
202 static int max8660_ldo67_is_enabled(struct regulator_dev
*rdev
)
204 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
205 u8 val
= max8660
->shadow_regs
[MAX8660_OVER2
];
206 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V6
) ? 2 : 4;
207 return !!(val
& mask
);
210 static int max8660_ldo67_enable(struct regulator_dev
*rdev
)
212 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
213 u8 bit
= (rdev_get_id(rdev
) == MAX8660_V6
) ? 2 : 4;
214 return max8660_write(max8660
, MAX8660_OVER2
, 0xff, bit
);
217 static int max8660_ldo67_disable(struct regulator_dev
*rdev
)
219 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
220 u8 mask
= (rdev_get_id(rdev
) == MAX8660_V6
) ? ~2 : ~4;
221 return max8660_write(max8660
, MAX8660_OVER2
, mask
, 0);
224 static int max8660_ldo67_get_voltage_sel(struct regulator_dev
*rdev
)
226 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
228 u8 shift
= (rdev_get_id(rdev
) == MAX8660_V6
) ? 0 : 4;
229 u8 selector
= (max8660
->shadow_regs
[MAX8660_L12VCR
] >> shift
) & 0xf;
233 static int max8660_ldo67_set_voltage_sel(struct regulator_dev
*rdev
,
234 unsigned int selector
)
236 struct max8660
*max8660
= rdev_get_drvdata(rdev
);
238 if (rdev_get_id(rdev
) == MAX8660_V6
)
239 return max8660_write(max8660
, MAX8660_L12VCR
, 0xf0, selector
);
241 return max8660_write(max8660
, MAX8660_L12VCR
, 0x0f,
245 static struct regulator_ops max8660_ldo67_ops
= {
246 .is_enabled
= max8660_ldo67_is_enabled
,
247 .enable
= max8660_ldo67_enable
,
248 .disable
= max8660_ldo67_disable
,
249 .list_voltage
= regulator_list_voltage_linear
,
250 .map_voltage
= regulator_map_voltage_linear
,
251 .get_voltage_sel
= max8660_ldo67_get_voltage_sel
,
252 .set_voltage_sel
= max8660_ldo67_set_voltage_sel
,
255 static const struct regulator_desc max8660_reg
[] = {
259 .ops
= &max8660_dcdc_ops
,
260 .type
= REGULATOR_VOLTAGE
,
261 .n_voltages
= MAX8660_DCDC_MAX_SEL
+ 1,
262 .owner
= THIS_MODULE
,
263 .min_uV
= MAX8660_DCDC_MIN_UV
,
264 .uV_step
= MAX8660_DCDC_STEP
,
269 .ops
= &max8660_dcdc_ops
,
270 .type
= REGULATOR_VOLTAGE
,
271 .n_voltages
= MAX8660_DCDC_MAX_SEL
+ 1,
272 .owner
= THIS_MODULE
,
273 .min_uV
= MAX8660_DCDC_MIN_UV
,
274 .uV_step
= MAX8660_DCDC_STEP
,
279 .ops
= &max8660_ldo5_ops
,
280 .type
= REGULATOR_VOLTAGE
,
281 .n_voltages
= MAX8660_LDO5_MAX_SEL
+ 1,
282 .owner
= THIS_MODULE
,
283 .min_uV
= MAX8660_LDO5_MIN_UV
,
284 .uV_step
= MAX8660_LDO5_STEP
,
289 .ops
= &max8660_ldo67_ops
,
290 .type
= REGULATOR_VOLTAGE
,
291 .n_voltages
= MAX8660_LDO67_MAX_SEL
+ 1,
292 .owner
= THIS_MODULE
,
293 .min_uV
= MAX8660_LDO67_MIN_UV
,
294 .uV_step
= MAX8660_LDO67_STEP
,
299 .ops
= &max8660_ldo67_ops
,
300 .type
= REGULATOR_VOLTAGE
,
301 .n_voltages
= MAX8660_LDO67_MAX_SEL
+ 1,
302 .owner
= THIS_MODULE
,
303 .min_uV
= MAX8660_LDO67_MIN_UV
,
304 .uV_step
= MAX8660_LDO67_STEP
,
308 static int max8660_probe(struct i2c_client
*client
,
309 const struct i2c_device_id
*i2c_id
)
311 struct regulator_dev
**rdev
;
312 struct max8660_platform_data
*pdata
= client
->dev
.platform_data
;
313 struct regulator_config config
= { };
314 struct max8660
*max8660
;
315 int boot_on
, i
, id
, ret
= -EINVAL
;
317 if (pdata
->num_subdevs
> MAX8660_V_END
) {
318 dev_err(&client
->dev
, "Too many regulators found!\n");
322 max8660
= devm_kzalloc(&client
->dev
, sizeof(struct max8660
) +
323 sizeof(struct regulator_dev
*) * MAX8660_V_END
,
328 max8660
->client
= client
;
329 rdev
= max8660
->rdev
;
331 if (pdata
->en34_is_high
) {
332 /* Simulate always on */
333 max8660
->shadow_regs
[MAX8660_OVER1
] = 5;
335 /* Otherwise devices can be toggled via software */
336 max8660_dcdc_ops
.enable
= max8660_dcdc_enable
;
337 max8660_dcdc_ops
.disable
= max8660_dcdc_disable
;
341 * First, set up shadow registers to prevent glitches. As some
342 * registers are shared between regulators, everything must be properly
343 * set up for all regulators in advance.
345 max8660
->shadow_regs
[MAX8660_ADTV1
] =
346 max8660
->shadow_regs
[MAX8660_ADTV2
] =
347 max8660
->shadow_regs
[MAX8660_SDTV1
] =
348 max8660
->shadow_regs
[MAX8660_SDTV2
] = 0x1b;
349 max8660
->shadow_regs
[MAX8660_MDTV1
] =
350 max8660
->shadow_regs
[MAX8660_MDTV2
] = 0x04;
352 for (i
= 0; i
< pdata
->num_subdevs
; i
++) {
354 if (!pdata
->subdevs
[i
].platform_data
)
357 boot_on
= pdata
->subdevs
[i
].platform_data
->constraints
.boot_on
;
359 switch (pdata
->subdevs
[i
].id
) {
362 max8660
->shadow_regs
[MAX8660_OVER1
] |= 1;
367 max8660
->shadow_regs
[MAX8660_OVER1
] |= 4;
375 max8660
->shadow_regs
[MAX8660_OVER2
] |= 2;
379 if (!strcmp(i2c_id
->name
, "max8661")) {
380 dev_err(&client
->dev
, "Regulator not on this chip!\n");
385 max8660
->shadow_regs
[MAX8660_OVER2
] |= 4;
389 dev_err(&client
->dev
, "invalid regulator %s\n",
390 pdata
->subdevs
[i
].name
);
395 /* Finally register devices */
396 for (i
= 0; i
< pdata
->num_subdevs
; i
++) {
398 id
= pdata
->subdevs
[i
].id
;
400 config
.dev
= &client
->dev
;
401 config
.init_data
= pdata
->subdevs
[i
].platform_data
;
402 config
.driver_data
= max8660
;
404 rdev
[i
] = regulator_register(&max8660_reg
[id
], &config
);
405 if (IS_ERR(rdev
[i
])) {
406 ret
= PTR_ERR(rdev
[i
]);
407 dev_err(&client
->dev
, "failed to register %s\n",
408 max8660_reg
[id
].name
);
413 i2c_set_clientdata(client
, max8660
);
418 regulator_unregister(rdev
[i
]);
423 static int max8660_remove(struct i2c_client
*client
)
425 struct max8660
*max8660
= i2c_get_clientdata(client
);
428 for (i
= 0; i
< MAX8660_V_END
; i
++)
429 if (max8660
->rdev
[i
])
430 regulator_unregister(max8660
->rdev
[i
]);
434 static const struct i2c_device_id max8660_id
[] = {
439 MODULE_DEVICE_TABLE(i2c
, max8660_id
);
441 static struct i2c_driver max8660_driver
= {
442 .probe
= max8660_probe
,
443 .remove
= max8660_remove
,
446 .owner
= THIS_MODULE
,
448 .id_table
= max8660_id
,
451 static int __init
max8660_init(void)
453 return i2c_add_driver(&max8660_driver
);
455 subsys_initcall(max8660_init
);
457 static void __exit
max8660_exit(void)
459 i2c_del_driver(&max8660_driver
);
461 module_exit(max8660_exit
);
463 /* Module information */
464 MODULE_DESCRIPTION("MAXIM 8660/8661 voltage regulator driver");
465 MODULE_AUTHOR("Wolfram Sang");
466 MODULE_LICENSE("GPL v2");