drivers/hwmon/pmbus/mpq8785.c

Source file repositories/reference/linux-study-clean/drivers/hwmon/pmbus/mpq8785.c

File Facts

System
Linux kernel
Corpus path
drivers/hwmon/pmbus/mpq8785.c
Extension
.c
Size
4877 bytes
Lines
194
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

if ((ret >> 5) == 1) {
			/*
			 * The MPQ8785 chip reports VOUT_MODE as VID mode, but the driver
			 * treats VID as direct mode. Without this, identification would fail
			 * due to mode mismatch.
			 * This override ensures the reported mode matches the driver
			 * configuration, allowing successful initialization.
			 */
			return PB_VOUT_MODE_DIRECT;
		}

		return ret;
	default:
		return -ENODATA;
	}
}

static int mpm82504_read_word_data(struct i2c_client *client, int page,
				   int phase, int reg)
{
	int ret;

	ret = pmbus_read_word_data(client, page, phase, reg);

	if (ret < 0 || reg != PMBUS_READ_TEMPERATURE_1)
		return ret;

	/* Fix PMBUS_READ_TEMPERATURE_1 signedness */
	return sign_extend32(ret, MPM82504_READ_TEMPERATURE_1_SIGN_POS) & 0xffff;
}

static struct pmbus_driver_info mpq8785_info = {
	.pages = 1,
	.format[PSC_VOLTAGE_IN] = direct,
	.format[PSC_CURRENT_OUT] = direct,
	.format[PSC_TEMPERATURE] = direct,
	.m[PSC_VOLTAGE_IN] = 4,
	.b[PSC_VOLTAGE_IN] = 0,
	.R[PSC_VOLTAGE_IN] = 1,
	.m[PSC_CURRENT_OUT] = 16,
	.b[PSC_CURRENT_OUT] = 0,
	.R[PSC_CURRENT_OUT] = 0,
	.m[PSC_TEMPERATURE] = 1,
	.b[PSC_TEMPERATURE] = 0,
	.R[PSC_TEMPERATURE] = 0,
	.func[0] =
		PMBUS_HAVE_VIN | PMBUS_HAVE_STATUS_INPUT |
		PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT |
		PMBUS_HAVE_IOUT | PMBUS_HAVE_STATUS_IOUT |
		PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP,
};

static const struct i2c_device_id mpq8785_id[] = {
	{ .name = "mpm3695", .driver_data = mpm3695 },
	{ .name = "mpm3695-25", .driver_data = mpm3695_25 },
	{ .name = "mpm82504", .driver_data = mpm82504 },
	{ .name = "mpq8785", .driver_data = mpq8785 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, mpq8785_id);

static const struct of_device_id __maybe_unused mpq8785_of_match[] = {
	{ .compatible = "mps,mpm3695", .data = (void *)mpm3695 },
	{ .compatible = "mps,mpm3695-25", .data = (void *)mpm3695_25 },
	{ .compatible = "mps,mpm82504", .data = (void *)mpm82504 },
	{ .compatible = "mps,mpq8785", .data = (void *)mpq8785 },
	{}
};
MODULE_DEVICE_TABLE(of, mpq8785_of_match);

static int mpq8785_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct pmbus_driver_info *info;
	enum chips chip_id;
	u32 voltage_scale;
	int ret;

	info = devm_kmemdup(dev, &mpq8785_info, sizeof(*info), GFP_KERNEL);
	if (!info)
		return -ENOMEM;

	if (dev->of_node)
		chip_id = (kernel_ulong_t)of_device_get_match_data(dev);
	else
		chip_id = (kernel_ulong_t)i2c_get_match_data(client);

	switch (chip_id) {
	case mpm3695:
	case mpm3695_25:

Annotation

Implementation Notes