/*
* hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
* Copyright (c) 2013,2014 Uplogix, Inc.
* David Barksdale <dbarksdale@uplogix.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*/
/*
* The Silicon Labs CP2112 chip is a USB HID device which provides an
* SMBus controller for talking to slave devices and 8 GPIO pins. The
* host communicates with the CP2112 via raw HID reports.
*
* Data Sheet:
* http://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
* Programming Interface Specification:
* http://www.silabs.com/Support%20Documents/TechnicalDocs/AN495.pdf
*/
#include <linux/gpio/driver.h>
#include <linux/hid.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/nls.h>
#include <linux/usb/ch9.h>
#include "hid-ids.h"
enum {
CP2112_GPIO_CONFIG = 0x02,
CP2112_GPIO_GET = 0x03,
CP2112_GPIO_SET = 0x04,
CP2112_GET_VERSION_INFO = 0x05,
CP2112_SMBUS_CONFIG = 0x06,
CP2112_DATA_READ_REQUEST = 0x10,
CP2112_DATA_WRITE_READ_REQUEST = 0x11,
CP2112_DATA_READ_FORCE_SEND = 0x12,
CP2112_DATA_READ_RESPONSE = 0x13,
CP2112_DATA_WRITE_REQUEST = 0x14,
CP2112_TRANSFER_STATUS_REQUEST = 0x15,
CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
CP2112_CANCEL_TRANSFER = 0x17,
CP2112_LOCK_BYTE = 0x20,
CP2112_USB_CONFIG = 0x21,
CP2112_MANUFACTURER_STRING = 0x22,
CP2112_PRODUCT_STRING = 0x23,
CP2112_SERIAL_STRING = 0x24,
};
enum {
STATUS0_IDLE = 0x00,
STATUS0_BUSY = 0x01,
STATUS0_COMPLETE = 0x02,
STATUS0_ERROR = 0x03,
};
enum {
STATUS1_TIMEOUT_NACK = 0x00,
STATUS1_TIMEOUT_BUS = 0x01,
STATUS1_ARBITRATION_LOST = 0x02,
STATUS1_READ_INCOMPLETE = 0x03,
STATUS1_WRITE_INCOMPLETE = 0x04,
STATUS1_SUCCESS = 0x05,
};
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