summaryrefslogtreecommitdiffstats
path: root/drivers/regulator/anatop-regulator.c
blob: 7d6478e6a5037ea446767ececa7ba0cdfea0d609 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
/*
 * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
 */

/*
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.

 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.

 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <linux/slab.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/mfd/syscon.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/machine.h>

#define LDO_RAMP_UP_UNIT_IN_CYCLES      64 /* 64 cycles per step */
#define LDO_RAMP_UP_FREQ_IN_MHZ         24 /* cycle based on 24M OSC */

#define LDO_POWER_GATE			0x00
#define LDO_FET_FULL_ON			0x1f

struct anatop_regulator {
	u32 control_reg;
	struct regmap *anatop;
	int vol_bit_shift;
	int vol_bit_width;
	u32 delay_reg;
	int delay_bit_shift;
	int delay_bit_width;
	int min_bit_val;
	int min_voltage;
	int max_voltage;
	struct regulator_desc rdesc;
	struct regulator_init_data *initdata;
	bool bypass;
	int sel;
};

static int anatop_regmap_set_voltage_time_sel(struct regulator_dev *reg,
	unsigned int old_sel,
	unsigned int new_sel)
{
	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
	u32 val;
	int ret = 0;

	/* check whether need to care about LDO ramp up speed */
	if (anatop_reg->delay_bit_width && new_sel > old_sel) {
		/*
		 * the delay for LDO ramp up time is
		 * based on the register setting, we need
		 * to calculate how many steps LDO need to
		 * ramp up, and how much delay needed. (us)
		 */
		regmap_read(anatop_reg->anatop, anatop_reg->delay_reg, &val);
		val = (val >> anatop_reg->delay_bit_shift) &
			((1 << anatop_reg->delay_bit_width) - 1);
		ret = (new_sel - old_sel) * (LDO_RAMP_UP_UNIT_IN_CYCLES <<
			val) / LDO_RAMP_UP_FREQ_IN_MHZ + 1;
	}

	return ret;
}

static int anatop_regmap_enable(struct regulator_dev *reg)
{
	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
	int sel;

	sel = anatop_reg->bypass ? LDO_FET_FULL_ON : anatop_reg->sel;
	return regulator_set_voltage_sel_regmap(reg, sel);
}

static int anatop_regmap_disable(struct regulator_dev *reg)
{
	return regulator_set_voltage_sel_regmap(reg, LDO_POWER_GATE);
}

static int anatop_regmap_is_enabled(struct regulator_dev *reg)
{
	return regulator_get_voltage_sel_regmap(reg) != LDO_POWER_GATE;
}

static int anatop_regmap_core_set_voltage_sel(struct regulator_dev *reg,
					      unsigned selector)
{
	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
	int ret;

	if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg)) {
		anatop_reg->sel = selector;
		return 0;
	}

	ret = regulator_set_voltage_sel_regmap(reg, selector);
	if (!ret)
		anatop_reg->sel = selector;
	return ret;
}

static int anatop_regmap_core_get_voltage_sel(struct regulator_dev *reg)
{
	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);

	if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg))
		return anatop_reg->sel;

	return regulator_get_voltage_sel_regmap(reg);
}

static int anatop_regmap_get_bypass(struct regulator_dev *reg, bool *enable)
{
	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
	int sel;

	sel = regulator_get_voltage_sel_regmap(reg);
	if (sel == LDO_FET_FULL_ON)
		WARN_ON(!anatop_reg->bypass);
	else if (sel != LDO_POWER_GATE)
		WARN_ON(anatop_reg->bypass);

	*enable = anatop_reg->bypass;
	return 0;
}

static int anatop_regmap_set_bypass(struct regulator_dev *reg, bool enable)
{
	struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
	int sel;

	if (enable == anatop_reg->bypass)
		return 0;

	sel = enable ? LDO_FET_FULL_ON : anatop_reg->sel;
	anatop_reg->bypass = enable;

	return regulator_set_voltage_sel_regmap(reg, sel);
}

static struct regulator_ops anatop_rops = {
	.set_voltage_sel = regulator_set_voltage_sel_regmap,
	.get_voltage_sel = regulator_get_voltage_sel_regmap,
	.list_voltage = regulator_list_voltage_linear,
	.map_voltage = regulator_map_voltage_linear,
};

static struct regulator_ops anatop_core_rops = {
	.enable = anatop_regmap_enable,
	.disable = anatop_regmap_disable,
	.is_enabled = anatop_regmap_is_enabled,
	.set_voltage_sel = anatop_regmap_core_set_voltage_sel,
	.set_voltage_time_sel = anatop_regmap_set_voltage_time_sel,
	.get_voltage_sel = anatop_regmap_core_get_voltage_sel,
	.list_voltage = regulator_list_voltage_linear,
	.map_voltage = regulator_map_voltage_linear,
	.get_bypass = anatop_regmap_get_bypass,
	.set_bypass = anatop_regmap_set_bypass,
};

static int anatop_regulator_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	struct device_node *anatop_np;
	struct regulator_desc *rdesc;
	struct regulator_dev *rdev;
	struct anatop_regulator *sreg;
	struct regulator_init_data *initdata;
	struct regulator_config config = { };
	int ret = 0;
	u32 val;

	sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
	if (!sreg)
		return -ENOMEM;

	rdesc = &sreg->rdesc;
	rdesc->type = REGULATOR_VOLTAGE;
	rdesc->owner = THIS_MODULE;

	of_property_read_string(np, "regulator-name", &rdesc->name);
	if (!rdesc->name) {
		dev_err(dev, "failed to get a regulator-name\n");
		return -EINVAL;
	}

	initdata = of_get_regulator_init_data(dev, np, rdesc);
	if (!initdata)
		return -ENOMEM;

	initdata->supply_regulator = "vin";
	sreg->initdata = initdata;

	anatop_np = of_get_parent(np);
	if (!anatop_np)
		return -ENODEV;
	sreg->anatop = syscon_node_to_regmap(anatop_np);
	of_node_put(anatop_np);
	if (IS_ERR(sreg->anatop))
		return PTR_ERR(sreg->anatop);

	ret = of_property_read_u32(np, "anatop-reg-offset",
				   &sreg->control_reg);
	if (ret) {
		dev_err(dev, "no anatop-reg-offset property set\n");
		return ret;
	}
	ret = of_property_read_u32(np, "anatop-vol-bit-width",
				   &sreg->vol_bit_width);
	if (ret) {
		dev_err(dev, "no anatop-vol-bit-width property set\n");
		return ret;
	}
	ret = of_property_read_u32(np, "anatop-vol-bit-shift",
				   &sreg->vol_bit_shift);
	if (ret) {
		dev_err(dev, "no anatop-vol-bit-shift property set\n");
		return ret;
	}
	ret = of_property_read_u32(np, "anatop-min-bit-val",
				   &sreg->min_bit_val);
	if (ret) {
		dev_err(dev, "no anatop-min-bit-val property set\n");
		return ret;
	}
	ret = of_property_read_u32(np, "anatop-min-voltage",
				   &sreg->min_voltage);
	if (ret) {
		dev_err(dev, "no anatop-min-voltage property set\n");
		return ret;
	}
	ret = of_property_read_u32(np, "anatop-max-voltage",
				   &sreg->max_voltage);
	if (ret) {
		dev_err(dev, "no anatop-max-voltage property set\n");
		return ret;
	}

	/* read LDO ramp up setting, only for core reg */
	of_property_read_u32(np, "anatop-delay-reg-offset",
			     &sreg->delay_reg);
	of_property_read_u32(np, "anatop-delay-bit-width",
			     &sreg->delay_bit_width);
	of_property_read_u32(np, "anatop-delay-bit-shift",
			     &sreg->delay_bit_shift);

	rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) / 25000 + 1
			    + sreg->min_bit_val;
	rdesc->min_uV = sreg->min_voltage;
	rdesc->uV_step = 25000;
	rdesc->linear_min_sel = sreg->min_bit_val;
	rdesc->vsel_reg = sreg->control_reg;
	rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) <<
			   sreg->vol_bit_shift;
	rdesc->min_dropout_uV = 125000;

	config.dev = &pdev->dev;
	config.init_data = initdata;
	config.driver_data = sreg;
	config.of_node = pdev->dev.of_node;
	config.regmap = sreg->anatop;

	/* Only core regulators have the ramp up delay configuration. */
	if (sreg->control_reg && sreg->delay_bit_width) {
		rdesc->ops = &anatop_core_rops;

		ret = regmap_read(config.regmap, rdesc->vsel_reg, &val);
		if (ret) {
			dev_err(dev, "failed to read initial state\n");
			return ret;
		}

		sreg->sel = (val & rdesc->vsel_mask) >> sreg->vol_bit_shift;
		if (sreg->sel == LDO_FET_FULL_ON) {
			sreg->sel = 0;
			sreg->bypass = true;
		}

		/*
		 * In case vddpu was disabled by the bootloader, we need to set
		 * a sane default until imx6-cpufreq was probed and changes the
		 * voltage to the correct value. In this case we set 1.25V.
		 */
		if (!sreg->sel && !strcmp(rdesc->name, "vddpu"))
			sreg->sel = 22;

		/* set the default voltage of the pcie phy to be 1.100v */
		if (!sreg->sel && !strcmp(rdesc->name, "vddpcie"))
			sreg->sel = 0x10;

		if (!sreg->bypass && !sreg->sel) {
			dev_err(&pdev->dev, "Failed to read a valid default voltage selector.\n");
			return -EINVAL;
		}
	} else {
		u32 enable_bit;

		rdesc->ops = &anatop_rops;

		if (!of_property_read_u32(np, "anatop-enable-bit",
					  &enable_bit)) {
			anatop_rops.enable  = regulator_enable_regmap;
			anatop_rops.disable = regulator_disable_regmap;
			anatop_rops.is_enabled = regulator_is_enabled_regmap;

			rdesc->enable_reg = sreg->control_reg;
			rdesc->enable_mask = BIT(enable_bit);
		}
	}

	/* register regulator */
	rdev = devm_regulator_register(dev, rdesc, &config);
	if (IS_ERR(rdev)) {
		dev_err(dev, "failed to register %s\n",
			rdesc->name);
		return PTR_ERR(rdev);
	}

	platform_set_drvdata(pdev, rdev);

	return 0;
}

static const struct of_device_id of_anatop_regulator_match_tbl[] = {
	{ .compatible = "fsl,anatop-regulator", },
	{ /* end */ }
};
MODULE_DEVICE_TABLE(of, of_anatop_regulator_match_tbl);

static struct platform_driver anatop_regulator_driver = {
	.driver = {
		.name	= "anatop_regulator",
		.of_match_table = of_anatop_regulator_match_tbl,
	},
	.probe	= anatop_regulator_probe,
};

static int __init anatop_regulator_init(void)
{
	return platform_driver_register(&anatop_regulator_driver);
}
postcore_initcall(anatop_regulator_init);

static void __exit anatop_regulator_exit(void)
{
	platform_driver_unregister(&anatop_regulator_driver);
}
module_exit(anatop_regulator_exit);

MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>");
MODULE_AUTHOR("Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
MODULE_DESCRIPTION("ANATOP Regulator driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:anatop_regulator");
OpenPOWER on IntegriCloud