1 /*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License version 2 as
4 * published by the Free Software Foundation.
5 *
6 * This program is distributed in the hope that it will be useful,
7 * but WITHOUT ANY WARRANTY; without even the implied warranty of
8 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
9 * GNU General Public License for more details.
10 *
11 * Copyright (C) 2012 ARM Limited
12 */
13
14 #define DRVNAME "vexpress-hwmon"
15 #define pr_fmt(fmt) DRVNAME ": " fmt
16
17 #include <linux/device.h>
18 #include <linux/err.h>
19 #include <linux/hwmon.h>
20 #include <linux/hwmon-sysfs.h>
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_device.h>
24 #include <linux/platform_device.h>
25 #include <linux/vexpress.h>
26
27 struct vexpress_hwmon_data {
28 struct device *hwmon_dev;
29 struct regmap *reg;
30 };
31
vexpress_hwmon_label_show(struct device * dev,struct device_attribute * dev_attr,char * buffer)32 static ssize_t vexpress_hwmon_label_show(struct device *dev,
33 struct device_attribute *dev_attr, char *buffer)
34 {
35 const char *label = of_get_property(dev->of_node, "label", NULL);
36
37 return snprintf(buffer, PAGE_SIZE, "%s\n", label);
38 }
39
vexpress_hwmon_u32_show(struct device * dev,struct device_attribute * dev_attr,char * buffer)40 static ssize_t vexpress_hwmon_u32_show(struct device *dev,
41 struct device_attribute *dev_attr, char *buffer)
42 {
43 struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
44 int err;
45 u32 value;
46
47 err = regmap_read(data->reg, 0, &value);
48 if (err)
49 return err;
50
51 return snprintf(buffer, PAGE_SIZE, "%u\n", value /
52 to_sensor_dev_attr(dev_attr)->index);
53 }
54
vexpress_hwmon_u64_show(struct device * dev,struct device_attribute * dev_attr,char * buffer)55 static ssize_t vexpress_hwmon_u64_show(struct device *dev,
56 struct device_attribute *dev_attr, char *buffer)
57 {
58 struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
59 int err;
60 u32 value_hi, value_lo;
61
62 err = regmap_read(data->reg, 0, &value_lo);
63 if (err)
64 return err;
65
66 err = regmap_read(data->reg, 1, &value_hi);
67 if (err)
68 return err;
69
70 return snprintf(buffer, PAGE_SIZE, "%llu\n",
71 div_u64(((u64)value_hi << 32) | value_lo,
72 to_sensor_dev_attr(dev_attr)->index));
73 }
74
vexpress_hwmon_attr_is_visible(struct kobject * kobj,struct attribute * attr,int index)75 static umode_t vexpress_hwmon_attr_is_visible(struct kobject *kobj,
76 struct attribute *attr, int index)
77 {
78 struct device *dev = kobj_to_dev(kobj);
79 struct device_attribute *dev_attr = container_of(attr,
80 struct device_attribute, attr);
81
82 if (dev_attr->show == vexpress_hwmon_label_show &&
83 !of_get_property(dev->of_node, "label", NULL))
84 return 0;
85
86 return attr->mode;
87 }
88
89 struct vexpress_hwmon_type {
90 const char *name;
91 const struct attribute_group **attr_groups;
92 };
93
94 #if !defined(CONFIG_REGULATOR_VEXPRESS)
95 static DEVICE_ATTR(in1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
96 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, vexpress_hwmon_u32_show,
97 NULL, 1000);
98 static struct attribute *vexpress_hwmon_attrs_volt[] = {
99 &dev_attr_in1_label.attr,
100 &sensor_dev_attr_in1_input.dev_attr.attr,
101 NULL
102 };
103 static struct attribute_group vexpress_hwmon_group_volt = {
104 .is_visible = vexpress_hwmon_attr_is_visible,
105 .attrs = vexpress_hwmon_attrs_volt,
106 };
107 static struct vexpress_hwmon_type vexpress_hwmon_volt = {
108 .name = "vexpress_volt",
109 .attr_groups = (const struct attribute_group *[]) {
110 &vexpress_hwmon_group_volt,
111 NULL,
112 },
113 };
114 #endif
115
116 static DEVICE_ATTR(curr1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
117 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, vexpress_hwmon_u32_show,
118 NULL, 1000);
119 static struct attribute *vexpress_hwmon_attrs_amp[] = {
120 &dev_attr_curr1_label.attr,
121 &sensor_dev_attr_curr1_input.dev_attr.attr,
122 NULL
123 };
124 static struct attribute_group vexpress_hwmon_group_amp = {
125 .is_visible = vexpress_hwmon_attr_is_visible,
126 .attrs = vexpress_hwmon_attrs_amp,
127 };
128 static struct vexpress_hwmon_type vexpress_hwmon_amp = {
129 .name = "vexpress_amp",
130 .attr_groups = (const struct attribute_group *[]) {
131 &vexpress_hwmon_group_amp,
132 NULL
133 },
134 };
135
136 static DEVICE_ATTR(temp1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
137 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, vexpress_hwmon_u32_show,
138 NULL, 1000);
139 static struct attribute *vexpress_hwmon_attrs_temp[] = {
140 &dev_attr_temp1_label.attr,
141 &sensor_dev_attr_temp1_input.dev_attr.attr,
142 NULL
143 };
144 static struct attribute_group vexpress_hwmon_group_temp = {
145 .is_visible = vexpress_hwmon_attr_is_visible,
146 .attrs = vexpress_hwmon_attrs_temp,
147 };
148 static struct vexpress_hwmon_type vexpress_hwmon_temp = {
149 .name = "vexpress_temp",
150 .attr_groups = (const struct attribute_group *[]) {
151 &vexpress_hwmon_group_temp,
152 NULL
153 },
154 };
155
156 static DEVICE_ATTR(power1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
157 static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, vexpress_hwmon_u32_show,
158 NULL, 1);
159 static struct attribute *vexpress_hwmon_attrs_power[] = {
160 &dev_attr_power1_label.attr,
161 &sensor_dev_attr_power1_input.dev_attr.attr,
162 NULL
163 };
164 static struct attribute_group vexpress_hwmon_group_power = {
165 .is_visible = vexpress_hwmon_attr_is_visible,
166 .attrs = vexpress_hwmon_attrs_power,
167 };
168 static struct vexpress_hwmon_type vexpress_hwmon_power = {
169 .name = "vexpress_power",
170 .attr_groups = (const struct attribute_group *[]) {
171 &vexpress_hwmon_group_power,
172 NULL
173 },
174 };
175
176 static DEVICE_ATTR(energy1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
177 static SENSOR_DEVICE_ATTR(energy1_input, S_IRUGO, vexpress_hwmon_u64_show,
178 NULL, 1);
179 static struct attribute *vexpress_hwmon_attrs_energy[] = {
180 &dev_attr_energy1_label.attr,
181 &sensor_dev_attr_energy1_input.dev_attr.attr,
182 NULL
183 };
184 static struct attribute_group vexpress_hwmon_group_energy = {
185 .is_visible = vexpress_hwmon_attr_is_visible,
186 .attrs = vexpress_hwmon_attrs_energy,
187 };
188 static struct vexpress_hwmon_type vexpress_hwmon_energy = {
189 .name = "vexpress_energy",
190 .attr_groups = (const struct attribute_group *[]) {
191 &vexpress_hwmon_group_energy,
192 NULL
193 },
194 };
195
196 static const struct of_device_id vexpress_hwmon_of_match[] = {
197 #if !defined(CONFIG_REGULATOR_VEXPRESS)
198 {
199 .compatible = "arm,vexpress-volt",
200 .data = &vexpress_hwmon_volt,
201 },
202 #endif
203 {
204 .compatible = "arm,vexpress-amp",
205 .data = &vexpress_hwmon_amp,
206 }, {
207 .compatible = "arm,vexpress-temp",
208 .data = &vexpress_hwmon_temp,
209 }, {
210 .compatible = "arm,vexpress-power",
211 .data = &vexpress_hwmon_power,
212 }, {
213 .compatible = "arm,vexpress-energy",
214 .data = &vexpress_hwmon_energy,
215 },
216 {}
217 };
218 MODULE_DEVICE_TABLE(of, vexpress_hwmon_of_match);
219
vexpress_hwmon_probe(struct platform_device * pdev)220 static int vexpress_hwmon_probe(struct platform_device *pdev)
221 {
222 const struct of_device_id *match;
223 struct vexpress_hwmon_data *data;
224 const struct vexpress_hwmon_type *type;
225
226 data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
227 if (!data)
228 return -ENOMEM;
229 platform_set_drvdata(pdev, data);
230
231 match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
232 if (!match)
233 return -ENODEV;
234 type = match->data;
235
236 data->reg = devm_regmap_init_vexpress_config(&pdev->dev);
237 if (IS_ERR(data->reg))
238 return PTR_ERR(data->reg);
239
240 data->hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev,
241 type->name, data, type->attr_groups);
242
243 return PTR_ERR_OR_ZERO(data->hwmon_dev);
244 }
245
246 static struct platform_driver vexpress_hwmon_driver = {
247 .probe = vexpress_hwmon_probe,
248 .driver = {
249 .name = DRVNAME,
250 .of_match_table = vexpress_hwmon_of_match,
251 },
252 };
253
254 module_platform_driver(vexpress_hwmon_driver);
255
256 MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
257 MODULE_DESCRIPTION("Versatile Express hwmon sensors driver");
258 MODULE_LICENSE("GPL");
259 MODULE_ALIAS("platform:vexpress-hwmon");
260