GNU Linux-libre 5.19-rc6-gnu
[releases.git] / drivers / mfd / tps65911-comparator.c
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * tps65910.c  --  TI TPS6591x
4  *
5  * Copyright 2010 Texas Instruments Inc.
6  *
7  * Author: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
8  */
9
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/slab.h>
14 #include <linux/err.h>
15 #include <linux/platform_device.h>
16 #include <linux/debugfs.h>
17 #include <linux/gpio.h>
18 #include <linux/mfd/tps65910.h>
19
20 #define COMP1                                   0
21 #define COMP2                                   1
22
23 /* Comparator 1 voltage selection table in millivolts */
24 static const u16 COMP_VSEL_TABLE[] = {
25         0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
26         2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
27         3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
28         3500,
29 };
30
31 struct comparator {
32         const char *name;
33         int reg;
34         int uV_max;
35         const u16 *vsel_table;
36 };
37
38 static struct comparator tps_comparators[] = {
39         {
40                 .name = "COMP1",
41                 .reg = TPS65911_VMBCH,
42                 .uV_max = 3500,
43                 .vsel_table = COMP_VSEL_TABLE,
44         },
45         {
46                 .name = "COMP2",
47                 .reg = TPS65911_VMBCH2,
48                 .uV_max = 3500,
49                 .vsel_table = COMP_VSEL_TABLE,
50         },
51 };
52
53 static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)
54 {
55         struct comparator tps_comp = tps_comparators[id];
56         int curr_voltage = 0;
57         int ret;
58         u8 index = 0, val;
59
60         while (curr_voltage < tps_comp.uV_max) {
61                 curr_voltage = tps_comp.vsel_table[index];
62                 if (curr_voltage >= voltage)
63                         break;
64                 else if (curr_voltage < voltage)
65                         index ++;
66         }
67
68         if (curr_voltage > tps_comp.uV_max)
69                 return -EINVAL;
70
71         val = index << 1;
72         ret = regmap_write(tps65910->regmap, tps_comp.reg, val);
73
74         return ret;
75 }
76
77 static int comp_threshold_get(struct tps65910 *tps65910, int id)
78 {
79         struct comparator tps_comp = tps_comparators[id];
80         unsigned int val;
81         int ret;
82
83         ret = regmap_read(tps65910->regmap, tps_comp.reg, &val);
84         if (ret < 0)
85                 return ret;
86
87         val >>= 1;
88         return tps_comp.vsel_table[val];
89 }
90
91 static ssize_t comp_threshold_show(struct device *dev,
92                                 struct device_attribute *attr, char *buf)
93 {
94         struct tps65910 *tps65910 = dev_get_drvdata(dev->parent);
95         struct attribute comp_attr = attr->attr;
96         int id, uVolt;
97
98         if (!strcmp(comp_attr.name, "comp1_threshold"))
99                 id = COMP1;
100         else if (!strcmp(comp_attr.name, "comp2_threshold"))
101                 id = COMP2;
102         else
103                 return -EINVAL;
104
105         uVolt = comp_threshold_get(tps65910, id);
106
107         return sprintf(buf, "%d\n", uVolt);
108 }
109
110 static DEVICE_ATTR(comp1_threshold, S_IRUGO, comp_threshold_show, NULL);
111 static DEVICE_ATTR(comp2_threshold, S_IRUGO, comp_threshold_show, NULL);
112
113 static int tps65911_comparator_probe(struct platform_device *pdev)
114 {
115         struct tps65910 *tps65910 = dev_get_drvdata(pdev->dev.parent);
116         struct tps65910_board *pdata = dev_get_platdata(tps65910->dev);
117         int ret;
118
119         ret = comp_threshold_set(tps65910, COMP1,  pdata->vmbch_threshold);
120         if (ret < 0) {
121                 dev_err(&pdev->dev, "cannot set COMP1 threshold\n");
122                 return ret;
123         }
124
125         ret = comp_threshold_set(tps65910, COMP2, pdata->vmbch2_threshold);
126         if (ret < 0) {
127                 dev_err(&pdev->dev, "cannot set COMP2 threshold\n");
128                 return ret;
129         }
130
131         /* Create sysfs entry */
132         ret = device_create_file(&pdev->dev, &dev_attr_comp1_threshold);
133         if (ret < 0)
134                 dev_err(&pdev->dev, "failed to add COMP1 sysfs file\n");
135
136         ret = device_create_file(&pdev->dev, &dev_attr_comp2_threshold);
137         if (ret < 0)
138                 dev_err(&pdev->dev, "failed to add COMP2 sysfs file\n");
139
140         return ret;
141 }
142
143 static int tps65911_comparator_remove(struct platform_device *pdev)
144 {
145         struct tps65910 *tps65910;
146
147         tps65910 = dev_get_drvdata(pdev->dev.parent);
148         device_remove_file(&pdev->dev, &dev_attr_comp2_threshold);
149         device_remove_file(&pdev->dev, &dev_attr_comp1_threshold);
150
151         return 0;
152 }
153
154 static struct platform_driver tps65911_comparator_driver = {
155         .driver = {
156                 .name = "tps65911-comparator",
157         },
158         .probe = tps65911_comparator_probe,
159         .remove = tps65911_comparator_remove,
160 };
161
162 static int __init tps65911_comparator_init(void)
163 {
164         return platform_driver_register(&tps65911_comparator_driver);
165 }
166 subsys_initcall(tps65911_comparator_init);
167
168 static void __exit tps65911_comparator_exit(void)
169 {
170         platform_driver_unregister(&tps65911_comparator_driver);
171 }
172 module_exit(tps65911_comparator_exit);
173
174 MODULE_AUTHOR("Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>");
175 MODULE_DESCRIPTION("TPS65911 comparator driver");
176 MODULE_LICENSE("GPL v2");
177 MODULE_ALIAS("platform:tps65911-comparator");