drivers/hid/hid-cp2112.c

Source file repositories/reference/linux-study-clean/drivers/hid/hid-cp2112.c

File Facts

System
Linux kernel
Corpus path
drivers/hid/hid-cp2112.c
Extension
.c
Size
38341 bytes
Lines
1498
Domain
Driver Families
Bucket
drivers/hid
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 cp2112_smbus_config_report {
	u8 report;		/* CP2112_SMBUS_CONFIG */
	__be32 clock_speed;	/* Hz */
	u8 device_address;	/* Stored in the upper 7 bits */
	u8 auto_send_read;	/* 1 = enabled, 0 = disabled */
	__be16 write_timeout;	/* ms, 0 = no timeout */
	__be16 read_timeout;	/* ms, 0 = no timeout */
	u8 scl_low_timeout;	/* 1 = enabled, 0 = disabled */
	__be16 retry_time;	/* # of retries, 0 = no limit */
} __packed;

struct cp2112_usb_config_report {
	u8 report;	/* CP2112_USB_CONFIG */
	__le16 vid;	/* Vendor ID */
	__le16 pid;	/* Product ID */
	u8 max_power;	/* Power requested in 2mA units */
	u8 power_mode;	/* 0x00 = bus powered
			   0x01 = self powered & regulator off
			   0x02 = self powered & regulator on */
	u8 release_major;
	u8 release_minor;
	u8 mask;	/* What fields to program */
} __packed;

struct cp2112_read_req_report {
	u8 report;	/* CP2112_DATA_READ_REQUEST */
	u8 slave_address;
	__be16 length;
} __packed;

struct cp2112_write_read_req_report {
	u8 report;	/* CP2112_DATA_WRITE_READ_REQUEST */
	u8 slave_address;
	__be16 length;
	u8 target_address_length;
	u8 target_address[16];
} __packed;

struct cp2112_write_req_report {
	u8 report;	/* CP2112_DATA_WRITE_REQUEST */
	u8 slave_address;
	u8 length;
	u8 data[61];
} __packed;

struct cp2112_force_read_report {
	u8 report;	/* CP2112_DATA_READ_FORCE_SEND */
	__be16 length;
} __packed;

struct cp2112_xfer_status_report {
	u8 report;	/* CP2112_TRANSFER_STATUS_RESPONSE */
	u8 status0;	/* STATUS0_* */
	u8 status1;	/* STATUS1_* */
	__be16 retries;
	__be16 length;
} __packed;

struct cp2112_string_report {
	u8 dummy;		/* force .string to be aligned */
	struct_group_attr(contents, __packed,
		u8 report;		/* CP2112_*_STRING */
		u8 length;		/* length in bytes of everything after .report */
		u8 type;		/* USB_DT_STRING */
		wchar_t string[30];	/* UTF16_LITTLE_ENDIAN string */
	);
} __packed;

/* Number of times to request transfer status before giving up waiting for a
   transfer to complete. This may need to be changed if SMBUS clock, retries,
   or read/write/scl_low timeout settings are changed. */
static const int XFER_STATUS_RETRIES = 10;

/* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
   CP2112_TRANSFER_STATUS_RESPONSE. */
static const int RESPONSE_TIMEOUT = 50;

static const struct hid_device_id cp2112_devices[] = {
	{ HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
	{ }
};
MODULE_DEVICE_TABLE(hid, cp2112_devices);

struct cp2112_device {
	struct i2c_adapter adap;
	struct hid_device *hdev;
	wait_queue_head_t wait;
	u8 read_data[61];
	u8 read_length;
	u8 hwversion;

Annotation

Implementation Notes