mc33xs2410_hwmon.c

  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
 30static 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
 44static 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
 60static 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, &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					       &reg_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, &reg_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
101static 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
120static 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
128static 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
137static 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
144static const struct hwmon_chip_info mc33xs2410_hwmon_chip_info = {
145	.ops = &mc33xs2410_hwmon_hwmon_ops,
146	.info = mc33xs2410_hwmon_info,
147};
148
149static 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
162static const struct auxiliary_device_id mc33xs2410_hwmon_ids[] = {
163	{
164		.name = "pwm_mc33xs2410.hwmon",
165	},
166	{ }
167};
168MODULE_DEVICE_TABLE(auxiliary, mc33xs2410_hwmon_ids);
169
170static struct auxiliary_driver mc33xs2410_hwmon_driver = {
171	.probe = mc33xs2410_hwmon_probe,
172	.id_table = mc33xs2410_hwmon_ids,
173};
174module_auxiliary_driver(mc33xs2410_hwmon_driver);
175
176MODULE_DESCRIPTION("NXP MC33XS2410 hwmon driver");
177MODULE_AUTHOR("Dimitri Fedrau <dimitri.fedrau@liebherr.com>");
178MODULE_LICENSE("GPL");