drivers/hwmon/surface_temp.c

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

File Facts

System
Linux kernel
Corpus path
drivers/hwmon/surface_temp.c
Extension
.c
Size
6574 bytes
Lines
236
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

struct ssam_tmp_get_name_rsp {
	__le16 unknown1;
	char unknown2;
	char name[SSAM_TMP_SENSOR_NAME_LENGTH];
} __packed;

static_assert(sizeof(struct ssam_tmp_get_name_rsp) == 21);

SSAM_DEFINE_SYNC_REQUEST_CL_R(__ssam_tmp_get_available_sensors, __le16, {
	.target_category = SSAM_SSH_TC_TMP,
	.command_id      = 0x04,
});

SSAM_DEFINE_SYNC_REQUEST_MD_R(__ssam_tmp_get_temperature, __le16, {
	.target_category = SSAM_SSH_TC_TMP,
	.command_id      = 0x01,
});

SSAM_DEFINE_SYNC_REQUEST_MD_R(__ssam_tmp_get_name, struct ssam_tmp_get_name_rsp, {
	.target_category = SSAM_SSH_TC_TMP,
	.command_id      = 0x0e,
});

static int ssam_tmp_get_available_sensors(struct ssam_device *sdev, s16 *sensors)
{
	__le16 sensors_le;
	int status;

	status = __ssam_tmp_get_available_sensors(sdev, &sensors_le);
	if (status)
		return status;

	*sensors = le16_to_cpu(sensors_le);
	return 0;
}

static int ssam_tmp_get_temperature(struct ssam_device *sdev, u8 iid, long *temperature)
{
	__le16 temp_le;
	int status;

	status = __ssam_tmp_get_temperature(sdev->ctrl, sdev->uid.target, iid, &temp_le);
	if (status)
		return status;

	/* Convert 1/10 °K to 1/1000 °C */
	*temperature = (le16_to_cpu(temp_le) - 2731) * 100L;
	return 0;
}

static int ssam_tmp_get_name(struct ssam_device *sdev, u8 iid, char *buf, size_t buf_len)
{
	struct ssam_tmp_get_name_rsp name_rsp;
	int status;

	status =  __ssam_tmp_get_name(sdev->ctrl, sdev->uid.target, iid, &name_rsp);
	if (status)
		return status;

	/*
	 * This should not fail unless the name in the returned struct is not
	 * null-terminated or someone changed something in the struct
	 * definitions above, since our buffer and struct have the same
	 * capacity by design. So if this fails, log an error message. Since
	 * the more likely cause is that the returned string isn't
	 * null-terminated, we might have received garbage (as opposed to just
	 * an incomplete string), so also fail the function.
	 */
	status = strscpy(buf, name_rsp.name, buf_len);
	if (status < 0) {
		dev_err(&sdev->dev, "received non-null-terminated sensor name string\n");
		return status;
	}

	return 0;
}

/* -- Driver.---------------------------------------------------------------- */

struct ssam_temp {
	struct ssam_device *sdev;
	s16 sensors;
	char names[SSAM_TMP_SENSOR_MAX_COUNT][SSAM_TMP_SENSOR_NAME_LENGTH];
};

static umode_t ssam_temp_hwmon_is_visible(const void *data,
					  enum hwmon_sensor_types type,
					  u32 attr, int channel)
{
	const struct ssam_temp *ssam_temp = data;

Annotation

Implementation Notes