drivers/hwmon/mc33xs2410_hwmon.c

Source file repositories/reference/linux-study-clean/drivers/hwmon/mc33xs2410_hwmon.c

File Facts

System
Linux kernel
Corpus path
drivers/hwmon/mc33xs2410_hwmon.c
Extension
.c
Size
4539 bytes
Lines
179
Domain
Driver Families
Bucket
drivers/hwmon
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (C) 2025 Liebherr-Electronics and Drives GmbH
 */

#include <linux/auxiliary_bus.h>
#include <linux/bitfield.h>
#include <linux/bitops.h>
#include <linux/hwmon.h>
#include <linux/mc33xs2410.h>
#include <linux/module.h>

/* ctrl registers */

#define MC33XS2410_TEMP_WT			0x29
#define MC33XS2410_TEMP_WT_MASK			GENMASK(7, 0)

/* diag registers */

/* chan in { 1 ... 4 } */
#define MC33XS2410_OUT_STA(chan)		(0x02 + (chan) - 1)
#define MC33XS2410_OUT_STA_OTW			BIT(8)

#define MC33XS2410_TS_TEMP_DIE			0x26
#define MC33XS2410_TS_TEMP_MASK			GENMASK(9, 0)

/* chan in { 1 ... 4 } */
#define MC33XS2410_TS_TEMP(chan)		(0x2f + (chan) - 1)

static const struct hwmon_channel_info * const mc33xs2410_hwmon_info[] = {
	HWMON_CHANNEL_INFO(temp,
			   HWMON_T_LABEL | HWMON_T_INPUT,
			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
			   HWMON_T_ALARM,
			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
			   HWMON_T_ALARM,
			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
			   HWMON_T_ALARM,
			   HWMON_T_LABEL | HWMON_T_INPUT | HWMON_T_MAX |
			   HWMON_T_ALARM),
	NULL,
};

static umode_t mc33xs2410_hwmon_is_visible(const void *data,
					   enum hwmon_sensor_types type,
					   u32 attr, int channel)
{
	switch (attr) {
	case hwmon_temp_input:
	case hwmon_temp_alarm:
	case hwmon_temp_label:
		return 0444;
	case hwmon_temp_max:
		return 0644;
	default:
		return 0;
	}
}

static int mc33xs2410_hwmon_read(struct device *dev,
				 enum hwmon_sensor_types type,
				 u32 attr, int channel, long *val)
{
	struct spi_device *spi = dev_get_drvdata(dev);
	u16 reg_val;
	int ret;
	u8 reg;

	switch (attr) {
	case hwmon_temp_input:
		reg = (channel == 0) ? MC33XS2410_TS_TEMP_DIE :
				       MC33XS2410_TS_TEMP(channel);
		ret = mc33xs2410_read_reg_diag(spi, reg, &reg_val);
		if (ret < 0)
			return ret;

		/* LSB is 0.25 degree celsius */
		*val = FIELD_GET(MC33XS2410_TS_TEMP_MASK, reg_val) * 250 - 40000;
		return 0;
	case hwmon_temp_alarm:
		ret = mc33xs2410_read_reg_diag(spi, MC33XS2410_OUT_STA(channel),
					       &reg_val);
		if (ret < 0)
			return ret;

		*val = FIELD_GET(MC33XS2410_OUT_STA_OTW, reg_val);
		return 0;
	case hwmon_temp_max:
		ret = mc33xs2410_read_reg_ctrl(spi, MC33XS2410_TEMP_WT, &reg_val);
		if (ret < 0)

Annotation

Implementation Notes