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Merge tag 'configfs-for-4.10' of git://git.infradead.org/users/hch/configfs
[karo-tx-linux.git] / drivers / regulator / anatop-regulator.c
1 /*
2  * Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
3  */
4
5 /*
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15
16  * You should have received a copy of the GNU General Public License along
17  * with this program; if not, write to the Free Software Foundation, Inc.,
18  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20
21 #include <linux/slab.h>
22 #include <linux/device.h>
23 #include <linux/module.h>
24 #include <linux/mfd/syscon.h>
25 #include <linux/err.h>
26 #include <linux/io.h>
27 #include <linux/platform_device.h>
28 #include <linux/of.h>
29 #include <linux/of_address.h>
30 #include <linux/regmap.h>
31 #include <linux/regulator/driver.h>
32 #include <linux/regulator/of_regulator.h>
33 #include <linux/regulator/machine.h>
34
35 #define LDO_RAMP_UP_UNIT_IN_CYCLES      64 /* 64 cycles per step */
36 #define LDO_RAMP_UP_FREQ_IN_MHZ         24 /* cycle based on 24M OSC */
37
38 #define LDO_POWER_GATE                  0x00
39 #define LDO_FET_FULL_ON                 0x1f
40
41 struct anatop_regulator {
42         const char *name;
43         u32 control_reg;
44         struct regmap *anatop;
45         int vol_bit_shift;
46         int vol_bit_width;
47         u32 delay_reg;
48         int delay_bit_shift;
49         int delay_bit_width;
50         int min_bit_val;
51         int min_voltage;
52         int max_voltage;
53         struct regulator_desc rdesc;
54         struct regulator_init_data *initdata;
55         bool bypass;
56         int sel;
57 };
58
59 static int anatop_regmap_set_voltage_time_sel(struct regulator_dev *reg,
60         unsigned int old_sel,
61         unsigned int new_sel)
62 {
63         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
64         u32 val;
65         int ret = 0;
66
67         /* check whether need to care about LDO ramp up speed */
68         if (anatop_reg->delay_bit_width && new_sel > old_sel) {
69                 /*
70                  * the delay for LDO ramp up time is
71                  * based on the register setting, we need
72                  * to calculate how many steps LDO need to
73                  * ramp up, and how much delay needed. (us)
74                  */
75                 regmap_read(anatop_reg->anatop, anatop_reg->delay_reg, &val);
76                 val = (val >> anatop_reg->delay_bit_shift) &
77                         ((1 << anatop_reg->delay_bit_width) - 1);
78                 ret = (new_sel - old_sel) * (LDO_RAMP_UP_UNIT_IN_CYCLES <<
79                         val) / LDO_RAMP_UP_FREQ_IN_MHZ + 1;
80         }
81
82         return ret;
83 }
84
85 static int anatop_regmap_enable(struct regulator_dev *reg)
86 {
87         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
88         int sel;
89
90         sel = anatop_reg->bypass ? LDO_FET_FULL_ON : anatop_reg->sel;
91         return regulator_set_voltage_sel_regmap(reg, sel);
92 }
93
94 static int anatop_regmap_disable(struct regulator_dev *reg)
95 {
96         return regulator_set_voltage_sel_regmap(reg, LDO_POWER_GATE);
97 }
98
99 static int anatop_regmap_is_enabled(struct regulator_dev *reg)
100 {
101         return regulator_get_voltage_sel_regmap(reg) != LDO_POWER_GATE;
102 }
103
104 static int anatop_regmap_core_set_voltage_sel(struct regulator_dev *reg,
105                                               unsigned selector)
106 {
107         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
108         int ret;
109
110         if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg)) {
111                 anatop_reg->sel = selector;
112                 return 0;
113         }
114
115         ret = regulator_set_voltage_sel_regmap(reg, selector);
116         if (!ret)
117                 anatop_reg->sel = selector;
118         return ret;
119 }
120
121 static int anatop_regmap_core_get_voltage_sel(struct regulator_dev *reg)
122 {
123         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
124
125         if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg))
126                 return anatop_reg->sel;
127
128         return regulator_get_voltage_sel_regmap(reg);
129 }
130
131 static int anatop_regmap_get_bypass(struct regulator_dev *reg, bool *enable)
132 {
133         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
134         int sel;
135
136         sel = regulator_get_voltage_sel_regmap(reg);
137         if (sel == LDO_FET_FULL_ON)
138                 WARN_ON(!anatop_reg->bypass);
139         else if (sel != LDO_POWER_GATE)
140                 WARN_ON(anatop_reg->bypass);
141
142         *enable = anatop_reg->bypass;
143         return 0;
144 }
145
146 static int anatop_regmap_set_bypass(struct regulator_dev *reg, bool enable)
147 {
148         struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
149         int sel;
150
151         if (enable == anatop_reg->bypass)
152                 return 0;
153
154         sel = enable ? LDO_FET_FULL_ON : anatop_reg->sel;
155         anatop_reg->bypass = enable;
156
157         return regulator_set_voltage_sel_regmap(reg, sel);
158 }
159
160 static struct regulator_ops anatop_rops = {
161         .set_voltage_sel = regulator_set_voltage_sel_regmap,
162         .get_voltage_sel = regulator_get_voltage_sel_regmap,
163         .list_voltage = regulator_list_voltage_linear,
164         .map_voltage = regulator_map_voltage_linear,
165 };
166
167 static struct regulator_ops anatop_core_rops = {
168         .enable = anatop_regmap_enable,
169         .disable = anatop_regmap_disable,
170         .is_enabled = anatop_regmap_is_enabled,
171         .set_voltage_sel = anatop_regmap_core_set_voltage_sel,
172         .set_voltage_time_sel = anatop_regmap_set_voltage_time_sel,
173         .get_voltage_sel = anatop_regmap_core_get_voltage_sel,
174         .list_voltage = regulator_list_voltage_linear,
175         .map_voltage = regulator_map_voltage_linear,
176         .get_bypass = anatop_regmap_get_bypass,
177         .set_bypass = anatop_regmap_set_bypass,
178 };
179
180 static int anatop_regulator_probe(struct platform_device *pdev)
181 {
182         struct device *dev = &pdev->dev;
183         struct device_node *np = dev->of_node;
184         struct device_node *anatop_np;
185         struct regulator_desc *rdesc;
186         struct regulator_dev *rdev;
187         struct anatop_regulator *sreg;
188         struct regulator_init_data *initdata;
189         struct regulator_config config = { };
190         int ret = 0;
191         u32 val;
192
193         sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
194         if (!sreg)
195                 return -ENOMEM;
196         sreg->name = of_get_property(np, "regulator-name", NULL);
197         rdesc = &sreg->rdesc;
198         rdesc->name = sreg->name;
199         rdesc->type = REGULATOR_VOLTAGE;
200         rdesc->owner = THIS_MODULE;
201
202         initdata = of_get_regulator_init_data(dev, np, rdesc);
203         initdata->supply_regulator = "vin";
204         sreg->initdata = initdata;
205
206         anatop_np = of_get_parent(np);
207         if (!anatop_np)
208                 return -ENODEV;
209         sreg->anatop = syscon_node_to_regmap(anatop_np);
210         of_node_put(anatop_np);
211         if (IS_ERR(sreg->anatop))
212                 return PTR_ERR(sreg->anatop);
213
214         ret = of_property_read_u32(np, "anatop-reg-offset",
215                                    &sreg->control_reg);
216         if (ret) {
217                 dev_err(dev, "no anatop-reg-offset property set\n");
218                 return ret;
219         }
220         ret = of_property_read_u32(np, "anatop-vol-bit-width",
221                                    &sreg->vol_bit_width);
222         if (ret) {
223                 dev_err(dev, "no anatop-vol-bit-width property set\n");
224                 return ret;
225         }
226         ret = of_property_read_u32(np, "anatop-vol-bit-shift",
227                                    &sreg->vol_bit_shift);
228         if (ret) {
229                 dev_err(dev, "no anatop-vol-bit-shift property set\n");
230                 return ret;
231         }
232         ret = of_property_read_u32(np, "anatop-min-bit-val",
233                                    &sreg->min_bit_val);
234         if (ret) {
235                 dev_err(dev, "no anatop-min-bit-val property set\n");
236                 return ret;
237         }
238         ret = of_property_read_u32(np, "anatop-min-voltage",
239                                    &sreg->min_voltage);
240         if (ret) {
241                 dev_err(dev, "no anatop-min-voltage property set\n");
242                 return ret;
243         }
244         ret = of_property_read_u32(np, "anatop-max-voltage",
245                                    &sreg->max_voltage);
246         if (ret) {
247                 dev_err(dev, "no anatop-max-voltage property set\n");
248                 return ret;
249         }
250
251         /* read LDO ramp up setting, only for core reg */
252         of_property_read_u32(np, "anatop-delay-reg-offset",
253                              &sreg->delay_reg);
254         of_property_read_u32(np, "anatop-delay-bit-width",
255                              &sreg->delay_bit_width);
256         of_property_read_u32(np, "anatop-delay-bit-shift",
257                              &sreg->delay_bit_shift);
258
259         rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) / 25000 + 1
260                             + sreg->min_bit_val;
261         rdesc->min_uV = sreg->min_voltage;
262         rdesc->uV_step = 25000;
263         rdesc->linear_min_sel = sreg->min_bit_val;
264         rdesc->vsel_reg = sreg->control_reg;
265         rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) <<
266                            sreg->vol_bit_shift;
267         rdesc->min_dropout_uV = 125000;
268
269         config.dev = &pdev->dev;
270         config.init_data = initdata;
271         config.driver_data = sreg;
272         config.of_node = pdev->dev.of_node;
273         config.regmap = sreg->anatop;
274
275         /* Only core regulators have the ramp up delay configuration. */
276         if (sreg->control_reg && sreg->delay_bit_width) {
277                 rdesc->ops = &anatop_core_rops;
278
279                 ret = regmap_read(config.regmap, rdesc->vsel_reg, &val);
280                 if (ret) {
281                         dev_err(dev, "failed to read initial state\n");
282                         return ret;
283                 }
284
285                 sreg->sel = (val & rdesc->vsel_mask) >> sreg->vol_bit_shift;
286                 if (sreg->sel == LDO_FET_FULL_ON) {
287                         sreg->sel = 0;
288                         sreg->bypass = true;
289                 }
290
291                 /*
292                  * In case vddpu was disabled by the bootloader, we need to set
293                  * a sane default until imx6-cpufreq was probed and changes the
294                  * voltage to the correct value. In this case we set 1.25V.
295                  */
296                 if (!sreg->sel && !strcmp(sreg->name, "vddpu"))
297                         sreg->sel = 22;
298
299                 if (!sreg->bypass && !sreg->sel) {
300                         dev_err(&pdev->dev, "Failed to read a valid default voltage selector.\n");
301                         return -EINVAL;
302                 }
303         } else {
304                 rdesc->ops = &anatop_rops;
305         }
306
307         /* register regulator */
308         rdev = devm_regulator_register(dev, rdesc, &config);
309         if (IS_ERR(rdev)) {
310                 dev_err(dev, "failed to register %s\n",
311                         rdesc->name);
312                 return PTR_ERR(rdev);
313         }
314
315         platform_set_drvdata(pdev, rdev);
316
317         return 0;
318 }
319
320 static const struct of_device_id of_anatop_regulator_match_tbl[] = {
321         { .compatible = "fsl,anatop-regulator", },
322         { /* end */ }
323 };
324 MODULE_DEVICE_TABLE(of, of_anatop_regulator_match_tbl);
325
326 static struct platform_driver anatop_regulator_driver = {
327         .driver = {
328                 .name   = "anatop_regulator",
329                 .of_match_table = of_anatop_regulator_match_tbl,
330         },
331         .probe  = anatop_regulator_probe,
332 };
333
334 static int __init anatop_regulator_init(void)
335 {
336         return platform_driver_register(&anatop_regulator_driver);
337 }
338 postcore_initcall(anatop_regulator_init);
339
340 static void __exit anatop_regulator_exit(void)
341 {
342         platform_driver_unregister(&anatop_regulator_driver);
343 }
344 module_exit(anatop_regulator_exit);
345
346 MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>");
347 MODULE_AUTHOR("Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
348 MODULE_DESCRIPTION("ANATOP Regulator driver");
349 MODULE_LICENSE("GPL v2");
350 MODULE_ALIAS("platform:anatop_regulator");