1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2025 Liebherr-Electronics and Drives GmbH
4 */
5
6 #include <linux/auxiliary_bus.h>
7 #include <linux/bitfield.h>
8 #include <linux/bitops.h>
9 #include <linux/hwmon.h>
10 #include <linux/mc33xs2410.h>
11 #include <linux/module.h>
12
13 /* ctrl registers */
14
15 #define MC33XS2410_TEMP_WT 0x29
16 #define MC33XS2410_TEMP_WT_MASK GENMASK(7, 0)
17
18 /* diag registers */
19
20 /* chan in { 1 ... 4 } */
21 #define MC33XS2410_OUT_STA(chan) (0x02 + (chan) - 1)
22 #define MC33XS2410_OUT_STA_OTW BIT(8)
23
24 #define MC33XS2410_TS_TEMP_DIE 0x26
25 #define MC33XS2410_TS_TEMP_MASK GENMASK(9, 0)
26
27 /* chan in { 1 ... 4 } */
28 #define MC33XS2410_TS_TEMP(chan) (0x2f + (chan) - 1)
29
30 static const struct hwmon_channel_info * const mc33xs2410_hwmon_info[] = {
31 HWMON_CHANNEL_INFO(temp,
32 HWMON_T_LABEL | HWMON_T_INPUT,
33 HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
34 HWMON_T_ALARM,
35 HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
36 HWMON_T_ALARM,
37 HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
38 HWMON_T_ALARM,
39 HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
40 HWMON_T_ALARM),
41 NULL,
42 };
43
mc33xs2410_hwmon_is_visible(const void * data,enum hwmon_sensor_types type,u32 attr,int channel)44 static umode_t mc33xs2410_hwmon_is_visible(const void *data,
45 enum hwmon_sensor_types type,
46 u32 attr, int channel)
47 {
48 switch (attr) {
49 case hwmon_temp_input:
50 case hwmon_temp_alarm:
51 case hwmon_temp_label:
52 return 0444;
53 case hwmon_temp_max:
54 return 0644;
55 default:
56 return 0;
57 }
58 }
59
mc33xs2410_hwmon_read(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long * val)60 static int mc33xs2410_hwmon_read(struct device *dev,
61 enum hwmon_sensor_types type,
62 u32 attr, int channel, long *val)
63 {
64 struct spi_device *spi = dev_get_drvdata(dev);
65 u16 reg_val;
66 int ret;
67 u8 reg;
68
69 switch (attr) {
70 case hwmon_temp_input:
71 reg = (channel == 0) ? MC33XS2410_TS_TEMP_DIE :
72 MC33XS2410_TS_TEMP(channel);
73 ret = mc33xs2410_read_reg_diag(spi, reg, ®_val);
74 if (ret < 0)
75 return ret;
76
77 /* LSB is 0.25 degree celsius */
78 *val = FIELD_GET(MC33XS2410_TS_TEMP_MASK, reg_val) * 250 - 40000;
79 return 0;
80 case hwmon_temp_alarm:
81 ret = mc33xs2410_read_reg_diag(spi, MC33XS2410_OUT_STA(channel),
82 ®_val);
83 if (ret < 0)
84 return ret;
85
86 *val = FIELD_GET(MC33XS2410_OUT_STA_OTW, reg_val);
87 return 0;
88 case hwmon_temp_max:
89 ret = mc33xs2410_read_reg_ctrl(spi, MC33XS2410_TEMP_WT, ®_val);
90 if (ret < 0)
91 return ret;
92
93 /* LSB is 1 degree celsius */
94 *val = FIELD_GET(MC33XS2410_TEMP_WT_MASK, reg_val) * 1000 - 40000;
95 return 0;
96 default:
97 return -EOPNOTSUPP;
98 }
99 }
100
mc33xs2410_hwmon_write(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,long val)101 static int mc33xs2410_hwmon_write(struct device *dev,
102 enum hwmon_sensor_types type, u32 attr,
103 int channel, long val)
104 {
105 struct spi_device *spi = dev_get_drvdata(dev);
106
107 switch (attr) {
108 case hwmon_temp_max:
109 val = clamp_val(val, -40000, 215000);
110
111 /* LSB is 1 degree celsius */
112 val = (val / 1000) + 40;
113 return mc33xs2410_modify_reg(spi, MC33XS2410_TEMP_WT,
114 MC33XS2410_TEMP_WT_MASK, val);
115 default:
116 return -EOPNOTSUPP;
117 }
118 }
119
120 static const char *const mc33xs2410_temp_label[] = {
121 "Central die temperature",
122 "Channel 1 temperature",
123 "Channel 2 temperature",
124 "Channel 3 temperature",
125 "Channel 4 temperature",
126 };
127
mc33xs2410_read_string(struct device * dev,enum hwmon_sensor_types type,u32 attr,int channel,const char ** str)128 static int mc33xs2410_read_string(struct device *dev,
129 enum hwmon_sensor_types type,
130 u32 attr, int channel, const char **str)
131 {
132 *str = mc33xs2410_temp_label[channel];
133
134 return 0;
135 }
136
137 static const struct hwmon_ops mc33xs2410_hwmon_hwmon_ops = {
138 .is_visible = mc33xs2410_hwmon_is_visible,
139 .read = mc33xs2410_hwmon_read,
140 .read_string = mc33xs2410_read_string,
141 .write = mc33xs2410_hwmon_write,
142 };
143
144 static const struct hwmon_chip_info mc33xs2410_hwmon_chip_info = {
145 .ops = &mc33xs2410_hwmon_hwmon_ops,
146 .info = mc33xs2410_hwmon_info,
147 };
148
mc33xs2410_hwmon_probe(struct auxiliary_device * adev,const struct auxiliary_device_id * id)149 static int mc33xs2410_hwmon_probe(struct auxiliary_device *adev,
150 const struct auxiliary_device_id *id)
151 {
152 struct device *dev = &adev->dev;
153 struct spi_device *spi = container_of(dev->parent, struct spi_device, dev);
154 struct device *hwmon;
155
156 hwmon = devm_hwmon_device_register_with_info(dev, NULL, spi,
157 &mc33xs2410_hwmon_chip_info,
158 NULL);
159 return PTR_ERR_OR_ZERO(hwmon);
160 }
161
162 static const struct auxiliary_device_id mc33xs2410_hwmon_ids[] = {
163 {
164 .name = "pwm_mc33xs2410.hwmon",
165 },
166 { }
167 };
168 MODULE_DEVICE_TABLE(auxiliary, mc33xs2410_hwmon_ids);
169
170 static struct auxiliary_driver mc33xs2410_hwmon_driver = {
171 .probe = mc33xs2410_hwmon_probe,
172 .id_table = mc33xs2410_hwmon_ids,
173 };
174 module_auxiliary_driver(mc33xs2410_hwmon_driver);
175
176 MODULE_DESCRIPTION("NXP MC33XS2410 hwmon driver");
177 MODULE_AUTHOR("Dimitri Fedrau <dimitri.fedrau@liebherr.com>");
178 MODULE_LICENSE("GPL");
179