1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * An hwmon driver for the NXP MC34VR500 PMIC
4 *
5 * Author: Mario Kicherer <dev@kicherer.org>
6 */
7
8#include <linux/bits.h>
9#include <linux/dev_printk.h>
10#include <linux/device.h>
11#include <linux/err.h>
12#include <linux/errno.h>
13#include <linux/hwmon.h>
14#include <linux/i2c.h>
15#include <linux/interrupt.h>
16#include <linux/irqreturn.h>
17#include <linux/module.h>
18#include <linux/of.h>
19#include <linux/regmap.h>
20
21#define MC34VR500_I2C_ADDR		0x08
22#define MC34VR500_DEVICEID_VALUE	0x14
23
24/* INTSENSE0 */
25#define ENS_BIT		BIT(0)
26#define LOWVINS_BIT	BIT(1)
27#define THERM110S_BIT	BIT(2)
28#define THERM120S_BIT	BIT(3)
29#define THERM125S_BIT	BIT(4)
30#define THERM130S_BIT	BIT(5)
31
32#define MC34VR500_DEVICEID	0x00
33
34#define MC34VR500_SILICONREVID	0x03
35#define MC34VR500_FABID		0x04
36#define MC34VR500_INTSTAT0	0x05
37#define MC34VR500_INTMASK0	0x06
38#define MC34VR500_INTSENSE0	0x07
39
40struct mc34vr500_data {
41	struct device *hwmon_dev;
42	struct regmap *regmap;
43};
44
45static irqreturn_t mc34vr500_process_interrupt(int irq, void *userdata)
46{
47	struct mc34vr500_data *data = (struct mc34vr500_data *)userdata;
48	unsigned int reg;
49	int ret;
50
51	ret = regmap_read(data->regmap, MC34VR500_INTSTAT0, &reg);
52	if (ret < 0)
53		return IRQ_HANDLED;
54
55	if (reg) {
56		if (reg & LOWVINS_BIT)
57			hwmon_notify_event(data->hwmon_dev, hwmon_in,
58					   hwmon_in_min_alarm, 0);
59
60		if (reg & THERM110S_BIT)
61			hwmon_notify_event(data->hwmon_dev, hwmon_temp,
62					   hwmon_temp_max_alarm, 0);
63
64		if (reg & THERM120S_BIT)
65			hwmon_notify_event(data->hwmon_dev, hwmon_temp,
66					   hwmon_temp_crit_alarm, 0);
67
68		if (reg & THERM130S_BIT)
69			hwmon_notify_event(data->hwmon_dev, hwmon_temp,
70					   hwmon_temp_emergency_alarm, 0);
71
72		/* write 1 to clear */
73		regmap_write(data->regmap, MC34VR500_INTSTAT0, LOWVINS_BIT |
74			     THERM110S_BIT | THERM120S_BIT | THERM130S_BIT);
75	}
76
77	return IRQ_HANDLED;
78}
79
80static umode_t mc34vr500_is_visible(const void *data,
81				    enum hwmon_sensor_types type,
82				    u32 attr, int channel)
83{
84	switch (attr) {
85	case hwmon_in_min_alarm:
86	case hwmon_temp_max_alarm:
87	case hwmon_temp_crit_alarm:
88	case hwmon_temp_emergency_alarm:
89		return 0444;
90	default:
91		break;
92	}
93
94	return 0;
95}
96
97static int mc34vr500_alarm_read(struct mc34vr500_data *data, int index,
98				long *val)
99{
100	unsigned int reg;
101	int ret;
102
103	ret = regmap_read(data->regmap, MC34VR500_INTSENSE0, &reg);
104	if (ret < 0)
105		return ret;
106
107	*val = !!(reg & index);
108
109	return 0;
110}
111
112static int mc34vr500_read(struct device *dev, enum hwmon_sensor_types type,
113			  u32 attr, int channel, long *val)
114{
115	struct mc34vr500_data *data = dev_get_drvdata(dev);
116
117	switch (type) {
118	case hwmon_in:
119		switch (attr) {
120		case hwmon_in_min_alarm:
121			return mc34vr500_alarm_read(data, LOWVINS_BIT, val);
122		default:
123			return -EOPNOTSUPP;
124		}
125	case hwmon_temp:
126		switch (attr) {
127		case hwmon_temp_max_alarm:
128			return mc34vr500_alarm_read(data, THERM110S_BIT, val);
129		case hwmon_temp_crit_alarm:
130			return mc34vr500_alarm_read(data, THERM120S_BIT, val);
131		case hwmon_temp_emergency_alarm:
132			return mc34vr500_alarm_read(data, THERM130S_BIT, val);
133		default:
134			return -EOPNOTSUPP;
135		}
136	default:
137		return -EOPNOTSUPP;
138	}
139}
140
141static const struct hwmon_channel_info * const mc34vr500_info[] = {
142	HWMON_CHANNEL_INFO(in, HWMON_I_MIN_ALARM),
143	HWMON_CHANNEL_INFO(temp, HWMON_T_MAX_ALARM | HWMON_T_CRIT_ALARM
144			   | HWMON_T_EMERGENCY_ALARM),
145	NULL,
146};
147
148static const struct hwmon_ops mc34vr500_hwmon_ops = {
149	.is_visible = mc34vr500_is_visible,
150	.read = mc34vr500_read,
151};
152
153static const struct hwmon_chip_info mc34vr500_chip_info = {
154	.ops = &mc34vr500_hwmon_ops,
155	.info = mc34vr500_info,
156};
157
158static const struct regmap_config mc34vr500_regmap_config = {
159	.reg_bits = 8,
160	.val_bits = 8,
161	.max_register = MC34VR500_INTSENSE0,
162};
163
164static int mc34vr500_probe(struct i2c_client *client)
165{
166	struct device *dev = &client->dev;
167	struct mc34vr500_data *data;
168	struct device *hwmon_dev;
169	int ret;
170	unsigned int reg, revid, fabid;
171	struct regmap *regmap;
172
173	regmap = devm_regmap_init_i2c(client, &mc34vr500_regmap_config);
174	if (IS_ERR(regmap))
175		return PTR_ERR(regmap);
176
177	data = devm_kzalloc(dev, sizeof(struct mc34vr500_data), GFP_KERNEL);
178	if (!data)
179		return -ENOMEM;
180
181	data->regmap = regmap;
182
183	ret = regmap_read(regmap, MC34VR500_DEVICEID, &reg);
184	if (ret < 0)
185		return ret;
186
187	if (reg != MC34VR500_DEVICEID_VALUE)
188		return -ENODEV;
189
190	ret = regmap_read(regmap, MC34VR500_SILICONREVID, &revid);
191	if (ret < 0)
192		return ret;
193
194	ret = regmap_read(regmap, MC34VR500_FABID, &fabid);
195	if (ret < 0)
196		return ret;
197
198	dev_dbg(dev, "mc34vr500: revid 0x%x fabid 0x%x\n", revid, fabid);
199
200	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
201							 data,
202							 &mc34vr500_chip_info,
203							 NULL);
204	if (IS_ERR(hwmon_dev))
205		return PTR_ERR(hwmon_dev);
206
207	data->hwmon_dev = hwmon_dev;
208
209	if (client->irq) {
210		ret = devm_request_threaded_irq(dev, client->irq, NULL,
211						mc34vr500_process_interrupt,
212						IRQF_TRIGGER_RISING |
213						IRQF_ONESHOT |
214						IRQF_SHARED,
215						dev_name(dev), data);
216		if (ret)
217			return ret;
218
219		/* write 1 to clear interrupts */
220		ret = regmap_write(regmap, MC34VR500_INTSTAT0, LOWVINS_BIT |
221				   THERM110S_BIT | THERM120S_BIT |
222				   THERM130S_BIT);
223		if (ret)
224			return ret;
225
226		/* unmask interrupts */
227		ret = regmap_write(regmap, MC34VR500_INTMASK0,
228				   (unsigned int) ~(LOWVINS_BIT | THERM110S_BIT |
229						    THERM120S_BIT | THERM130S_BIT));
230		if (ret)
231			return ret;
232	}
233
234	return 0;
235}
236
237static const struct i2c_device_id mc34vr500_id[] = {
238	{ "mc34vr500", 0 },
239	{ },
240};
241MODULE_DEVICE_TABLE(i2c, mc34vr500_id);
242
243static const struct of_device_id __maybe_unused mc34vr500_of_match[] = {
244	{ .compatible = "nxp,mc34vr500" },
245	{ },
246};
247MODULE_DEVICE_TABLE(of, mc34vr500_of_match);
248
249static struct i2c_driver mc34vr500_driver = {
250	.driver = {
251		   .name = "mc34vr500",
252		   .of_match_table = of_match_ptr(mc34vr500_of_match),
253		    },
254	.probe = mc34vr500_probe,
255	.id_table = mc34vr500_id,
256};
257
258module_i2c_driver(mc34vr500_driver);
259
260MODULE_AUTHOR("Mario Kicherer <dev@kicherer.org>");
261
262MODULE_DESCRIPTION("MC34VR500 driver");
263MODULE_LICENSE("GPL");
264