mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 04:18:39 +08:00
HID: mcp2221: add usb to i2c-smbus host bridge
MCP2221 is a USB HID to I2C/SMbus host bridge device. This commit implements i2c and smbus host adapter support. 7-bit address and i2c multi-message transaction is also supported. Signed-off-by: Rishi Gupta <gupt21@gmail.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
This commit is contained in:
parent
278de45e14
commit
67a95c2146
@ -10236,6 +10236,13 @@ F: drivers/net/can/m_can/m_can.c
|
||||
F: drivers/net/can/m_can/m_can.h
|
||||
F: drivers/net/can/m_can/m_can_platform.c
|
||||
|
||||
MCP2221A MICROCHIP USB-HID TO I2C BRIDGE DRIVER
|
||||
M: Rishi Gupta <gupt21@gmail.com>
|
||||
L: linux-i2c@vger.kernel.org
|
||||
L: linux-input@vger.kernel.org
|
||||
S: Maintained
|
||||
F: drivers/hid/hid-mcp2221.c
|
||||
|
||||
MCP4018 AND MCP4531 MICROCHIP DIGITAL POTENTIOMETER DRIVERS
|
||||
M: Peter Rosin <peda@axentia.se>
|
||||
L: linux-iio@vger.kernel.org
|
||||
|
@ -1145,6 +1145,16 @@ config HID_ALPS
|
||||
Say Y here if you have a Alps touchpads over i2c-hid or usbhid
|
||||
and want support for its special functionalities.
|
||||
|
||||
config HID_MCP2221
|
||||
tristate "Microchip MCP2221 HID USB-to-I2C/SMbus host support"
|
||||
depends on USB_HID && I2C
|
||||
---help---
|
||||
Provides I2C and SMBUS host adapter functionality over USB-HID
|
||||
through MCP2221 device.
|
||||
|
||||
To compile this driver as a module, choose M here: the module
|
||||
will be called hid-mcp2221.ko.
|
||||
|
||||
endmenu
|
||||
|
||||
endif # HID
|
||||
|
@ -70,6 +70,7 @@ obj-$(CONFIG_HID_LOGITECH_HIDPP) += hid-logitech-hidpp.o
|
||||
obj-$(CONFIG_HID_MACALLY) += hid-macally.o
|
||||
obj-$(CONFIG_HID_MAGICMOUSE) += hid-magicmouse.o
|
||||
obj-$(CONFIG_HID_MALTRON) += hid-maltron.o
|
||||
obj-$(CONFIG_HID_MCP2221) += hid-mcp2221.o
|
||||
obj-$(CONFIG_HID_MAYFLASH) += hid-mf.o
|
||||
obj-$(CONFIG_HID_MICROSOFT) += hid-microsoft.o
|
||||
obj-$(CONFIG_HID_MONTEREY) += hid-monterey.o
|
||||
|
@ -819,6 +819,7 @@
|
||||
#define USB_DEVICE_ID_PICK16F1454 0x0042
|
||||
#define USB_DEVICE_ID_PICK16F1454_V2 0xf2f7
|
||||
#define USB_DEVICE_ID_LUXAFOR 0xf372
|
||||
#define USB_DEVICE_ID_MCP2221 0x00dd
|
||||
|
||||
#define USB_VENDOR_ID_MICROSOFT 0x045e
|
||||
#define USB_DEVICE_ID_SIDEWINDER_GV 0x003b
|
||||
|
742
drivers/hid/hid-mcp2221.c
Normal file
742
drivers/hid/hid-mcp2221.c
Normal file
@ -0,0 +1,742 @@
|
||||
// SPDX-License-Identifier: GPL-2.0-only
|
||||
/*
|
||||
* MCP2221A - Microchip USB to I2C Host Protocol Bridge
|
||||
*
|
||||
* Copyright (c) 2020, Rishi Gupta <gupt21@gmail.com>
|
||||
*
|
||||
* Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/20005565B.pdf
|
||||
*/
|
||||
|
||||
#include <linux/module.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/completion.h>
|
||||
#include <linux/delay.h>
|
||||
#include <linux/hid.h>
|
||||
#include <linux/hidraw.h>
|
||||
#include <linux/i2c.h>
|
||||
#include "hid-ids.h"
|
||||
|
||||
/* Commands codes in a raw output report */
|
||||
enum {
|
||||
MCP2221_I2C_WR_DATA = 0x90,
|
||||
MCP2221_I2C_WR_NO_STOP = 0x94,
|
||||
MCP2221_I2C_RD_DATA = 0x91,
|
||||
MCP2221_I2C_RD_RPT_START = 0x93,
|
||||
MCP2221_I2C_GET_DATA = 0x40,
|
||||
MCP2221_I2C_PARAM_OR_STATUS = 0x10,
|
||||
MCP2221_I2C_SET_SPEED = 0x20,
|
||||
MCP2221_I2C_CANCEL = 0x10,
|
||||
};
|
||||
|
||||
/* Response codes in a raw input report */
|
||||
enum {
|
||||
MCP2221_SUCCESS = 0x00,
|
||||
MCP2221_I2C_ENG_BUSY = 0x01,
|
||||
MCP2221_I2C_START_TOUT = 0x12,
|
||||
MCP2221_I2C_STOP_TOUT = 0x62,
|
||||
MCP2221_I2C_WRADDRL_TOUT = 0x23,
|
||||
MCP2221_I2C_WRDATA_TOUT = 0x44,
|
||||
MCP2221_I2C_WRADDRL_NACK = 0x25,
|
||||
MCP2221_I2C_MASK_ADDR_NACK = 0x40,
|
||||
MCP2221_I2C_WRADDRL_SEND = 0x21,
|
||||
MCP2221_I2C_ADDR_NACK = 0x25,
|
||||
MCP2221_I2C_READ_COMPL = 0x55,
|
||||
};
|
||||
|
||||
/*
|
||||
* There is no way to distinguish responses. Therefore next command
|
||||
* is sent only after response to previous has been received. Mutex
|
||||
* lock is used for this purpose mainly.
|
||||
*/
|
||||
struct mcp2221 {
|
||||
struct hid_device *hdev;
|
||||
struct i2c_adapter adapter;
|
||||
struct mutex lock;
|
||||
struct completion wait_in_report;
|
||||
u8 *rxbuf;
|
||||
u8 txbuf[64];
|
||||
int rxbuf_idx;
|
||||
int status;
|
||||
u8 cur_i2c_clk_div;
|
||||
};
|
||||
|
||||
/*
|
||||
* Default i2c bus clock frequency 400 kHz. Modify this if you
|
||||
* want to set some other frequency (min 50 kHz - max 400 kHz).
|
||||
*/
|
||||
static uint i2c_clk_freq = 400;
|
||||
|
||||
/* Synchronously send output report to the device */
|
||||
static int mcp_send_report(struct mcp2221 *mcp,
|
||||
u8 *out_report, size_t len)
|
||||
{
|
||||
u8 *buf;
|
||||
int ret;
|
||||
|
||||
buf = kmemdup(out_report, len, GFP_KERNEL);
|
||||
if (!buf)
|
||||
return -ENOMEM;
|
||||
|
||||
/* mcp2221 uses interrupt endpoint for out reports */
|
||||
ret = hid_hw_output_report(mcp->hdev, buf, len);
|
||||
kfree(buf);
|
||||
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* Send o/p report to the device and wait for i/p report to be
|
||||
* received from the device. If the device does not respond,
|
||||
* we timeout.
|
||||
*/
|
||||
static int mcp_send_data_req_status(struct mcp2221 *mcp,
|
||||
u8 *out_report, int len)
|
||||
{
|
||||
int ret;
|
||||
unsigned long t;
|
||||
|
||||
reinit_completion(&mcp->wait_in_report);
|
||||
|
||||
ret = mcp_send_report(mcp, out_report, len);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
t = wait_for_completion_timeout(&mcp->wait_in_report,
|
||||
msecs_to_jiffies(4000));
|
||||
if (!t)
|
||||
return -ETIMEDOUT;
|
||||
|
||||
return mcp->status;
|
||||
}
|
||||
|
||||
/* Check pass/fail for actual communication with i2c slave */
|
||||
static int mcp_chk_last_cmd_status(struct mcp2221 *mcp)
|
||||
{
|
||||
memset(mcp->txbuf, 0, 8);
|
||||
mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
|
||||
|
||||
return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
|
||||
}
|
||||
|
||||
/* Cancels last command releasing i2c bus just in case occupied */
|
||||
static int mcp_cancel_last_cmd(struct mcp2221 *mcp)
|
||||
{
|
||||
memset(mcp->txbuf, 0, 8);
|
||||
mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
|
||||
mcp->txbuf[2] = MCP2221_I2C_CANCEL;
|
||||
|
||||
return mcp_send_data_req_status(mcp, mcp->txbuf, 8);
|
||||
}
|
||||
|
||||
static int mcp_set_i2c_speed(struct mcp2221 *mcp)
|
||||
{
|
||||
int ret;
|
||||
|
||||
memset(mcp->txbuf, 0, 8);
|
||||
mcp->txbuf[0] = MCP2221_I2C_PARAM_OR_STATUS;
|
||||
mcp->txbuf[3] = MCP2221_I2C_SET_SPEED;
|
||||
mcp->txbuf[4] = mcp->cur_i2c_clk_div;
|
||||
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 8);
|
||||
if (ret) {
|
||||
/* Small delay is needed here */
|
||||
usleep_range(980, 1000);
|
||||
mcp_cancel_last_cmd(mcp);
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/*
|
||||
* An output report can contain minimum 1 and maximum 60 user data
|
||||
* bytes. If the number of data bytes is more then 60, we send it
|
||||
* in chunks of 60 bytes. Last chunk may contain exactly 60 or less
|
||||
* bytes. Total number of bytes is informed in very first report to
|
||||
* mcp2221, from that point onwards it first collect all the data
|
||||
* from host and then send to i2c slave device.
|
||||
*/
|
||||
static int mcp_i2c_write(struct mcp2221 *mcp,
|
||||
struct i2c_msg *msg, int type, u8 last_status)
|
||||
{
|
||||
int ret, len, idx, sent;
|
||||
|
||||
idx = 0;
|
||||
sent = 0;
|
||||
if (msg->len < 60)
|
||||
len = msg->len;
|
||||
else
|
||||
len = 60;
|
||||
|
||||
do {
|
||||
mcp->txbuf[0] = type;
|
||||
mcp->txbuf[1] = msg->len & 0xff;
|
||||
mcp->txbuf[2] = msg->len >> 8;
|
||||
mcp->txbuf[3] = (u8)(msg->addr << 1);
|
||||
|
||||
memcpy(&mcp->txbuf[4], &msg->buf[idx], len);
|
||||
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, len + 4);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
usleep_range(980, 1000);
|
||||
|
||||
if (last_status) {
|
||||
ret = mcp_chk_last_cmd_status(mcp);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
sent = sent + len;
|
||||
if (sent >= msg->len)
|
||||
break;
|
||||
|
||||
idx = idx + len;
|
||||
if ((msg->len - sent) < 60)
|
||||
len = msg->len - sent;
|
||||
else
|
||||
len = 60;
|
||||
|
||||
/*
|
||||
* Testing shows delay is needed between successive writes
|
||||
* otherwise next write fails on first-try from i2c core.
|
||||
* This value is obtained through automated stress testing.
|
||||
*/
|
||||
usleep_range(980, 1000);
|
||||
} while (len > 0);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* Device reads all data (0 - 65535 bytes) from i2c slave device and
|
||||
* stores it in device itself. This data is read back from device to
|
||||
* host in multiples of 60 bytes using input reports.
|
||||
*/
|
||||
static int mcp_i2c_smbus_read(struct mcp2221 *mcp,
|
||||
struct i2c_msg *msg, int type, u16 smbus_addr,
|
||||
u8 smbus_len, u8 *smbus_buf)
|
||||
{
|
||||
int ret;
|
||||
u16 total_len;
|
||||
|
||||
mcp->txbuf[0] = type;
|
||||
if (msg) {
|
||||
mcp->txbuf[1] = msg->len & 0xff;
|
||||
mcp->txbuf[2] = msg->len >> 8;
|
||||
mcp->txbuf[3] = (u8)(msg->addr << 1);
|
||||
total_len = msg->len;
|
||||
mcp->rxbuf = msg->buf;
|
||||
} else {
|
||||
mcp->txbuf[1] = smbus_len;
|
||||
mcp->txbuf[2] = 0;
|
||||
mcp->txbuf[3] = (u8)(smbus_addr << 1);
|
||||
total_len = smbus_len;
|
||||
mcp->rxbuf = smbus_buf;
|
||||
}
|
||||
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 4);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
mcp->rxbuf_idx = 0;
|
||||
|
||||
do {
|
||||
memset(mcp->txbuf, 0, 4);
|
||||
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
||||
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = mcp_chk_last_cmd_status(mcp);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
usleep_range(980, 1000);
|
||||
} while (mcp->rxbuf_idx < total_len);
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int mcp_i2c_xfer(struct i2c_adapter *adapter,
|
||||
struct i2c_msg msgs[], int num)
|
||||
{
|
||||
int ret;
|
||||
struct mcp2221 *mcp = i2c_get_adapdata(adapter);
|
||||
|
||||
hid_hw_power(mcp->hdev, PM_HINT_FULLON);
|
||||
|
||||
mutex_lock(&mcp->lock);
|
||||
|
||||
/* Setting speed before every transaction is required for mcp2221 */
|
||||
ret = mcp_set_i2c_speed(mcp);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
if (num == 1) {
|
||||
if (msgs->flags & I2C_M_RD) {
|
||||
ret = mcp_i2c_smbus_read(mcp, msgs, MCP2221_I2C_RD_DATA,
|
||||
0, 0, NULL);
|
||||
} else {
|
||||
ret = mcp_i2c_write(mcp, msgs, MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
if (ret)
|
||||
goto exit;
|
||||
ret = num;
|
||||
} else if (num == 2) {
|
||||
/* Ex transaction; send reg address and read its contents */
|
||||
if (msgs[0].addr == msgs[1].addr &&
|
||||
!(msgs[0].flags & I2C_M_RD) &&
|
||||
(msgs[1].flags & I2C_M_RD)) {
|
||||
|
||||
ret = mcp_i2c_write(mcp, &msgs[0],
|
||||
MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, &msgs[1],
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
0, 0, NULL);
|
||||
if (ret)
|
||||
goto exit;
|
||||
ret = num;
|
||||
} else {
|
||||
dev_err(&adapter->dev,
|
||||
"unsupported multi-msg i2c transaction\n");
|
||||
ret = -EOPNOTSUPP;
|
||||
}
|
||||
} else {
|
||||
dev_err(&adapter->dev,
|
||||
"unsupported multi-msg i2c transaction\n");
|
||||
ret = -EOPNOTSUPP;
|
||||
}
|
||||
|
||||
exit:
|
||||
hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
|
||||
mutex_unlock(&mcp->lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int mcp_smbus_write(struct mcp2221 *mcp, u16 addr,
|
||||
u8 command, u8 *buf, u8 len, int type,
|
||||
u8 last_status)
|
||||
{
|
||||
int data_len, ret;
|
||||
|
||||
mcp->txbuf[0] = type;
|
||||
mcp->txbuf[1] = len + 1; /* 1 is due to command byte itself */
|
||||
mcp->txbuf[2] = 0;
|
||||
mcp->txbuf[3] = (u8)(addr << 1);
|
||||
mcp->txbuf[4] = command;
|
||||
|
||||
switch (len) {
|
||||
case 0:
|
||||
data_len = 5;
|
||||
break;
|
||||
case 1:
|
||||
mcp->txbuf[5] = buf[0];
|
||||
data_len = 6;
|
||||
break;
|
||||
case 2:
|
||||
mcp->txbuf[5] = buf[0];
|
||||
mcp->txbuf[6] = buf[1];
|
||||
data_len = 7;
|
||||
break;
|
||||
default:
|
||||
memcpy(&mcp->txbuf[5], buf, len);
|
||||
data_len = len + 5;
|
||||
}
|
||||
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, data_len);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (last_status) {
|
||||
usleep_range(980, 1000);
|
||||
|
||||
ret = mcp_chk_last_cmd_status(mcp);
|
||||
if (ret)
|
||||
return ret;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int mcp_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
|
||||
unsigned short flags, char read_write,
|
||||
u8 command, int size,
|
||||
union i2c_smbus_data *data)
|
||||
{
|
||||
int ret;
|
||||
struct mcp2221 *mcp = i2c_get_adapdata(adapter);
|
||||
|
||||
hid_hw_power(mcp->hdev, PM_HINT_FULLON);
|
||||
|
||||
mutex_lock(&mcp->lock);
|
||||
|
||||
ret = mcp_set_i2c_speed(mcp);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
switch (size) {
|
||||
|
||||
case I2C_SMBUS_QUICK:
|
||||
if (read_write == I2C_SMBUS_READ)
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
|
||||
addr, 0, &data->byte);
|
||||
else
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_DATA, 1);
|
||||
break;
|
||||
case I2C_SMBUS_BYTE:
|
||||
if (read_write == I2C_SMBUS_READ)
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL, MCP2221_I2C_RD_DATA,
|
||||
addr, 1, &data->byte);
|
||||
else
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_DATA, 1);
|
||||
break;
|
||||
case I2C_SMBUS_BYTE_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, 1, &data->byte);
|
||||
} else {
|
||||
ret = mcp_smbus_write(mcp, addr, command, &data->byte,
|
||||
1, MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_WORD_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, 2, (u8 *)&data->word);
|
||||
} else {
|
||||
ret = mcp_smbus_write(mcp, addr, command,
|
||||
(u8 *)&data->word, 2,
|
||||
MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_BLOCK_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
mcp->rxbuf_idx = 0;
|
||||
mcp->rxbuf = data->block;
|
||||
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
} else {
|
||||
if (!data->block[0]) {
|
||||
ret = -EINVAL;
|
||||
goto exit;
|
||||
}
|
||||
ret = mcp_smbus_write(mcp, addr, command, data->block,
|
||||
data->block[0] + 1,
|
||||
MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_I2C_BLOCK_DATA:
|
||||
if (read_write == I2C_SMBUS_READ) {
|
||||
ret = mcp_smbus_write(mcp, addr, command, NULL,
|
||||
0, MCP2221_I2C_WR_NO_STOP, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
mcp->rxbuf_idx = 0;
|
||||
mcp->rxbuf = data->block;
|
||||
mcp->txbuf[0] = MCP2221_I2C_GET_DATA;
|
||||
ret = mcp_send_data_req_status(mcp, mcp->txbuf, 1);
|
||||
if (ret)
|
||||
goto exit;
|
||||
} else {
|
||||
if (!data->block[0]) {
|
||||
ret = -EINVAL;
|
||||
goto exit;
|
||||
}
|
||||
ret = mcp_smbus_write(mcp, addr, command,
|
||||
&data->block[1], data->block[0],
|
||||
MCP2221_I2C_WR_DATA, 1);
|
||||
}
|
||||
break;
|
||||
case I2C_SMBUS_PROC_CALL:
|
||||
ret = mcp_smbus_write(mcp, addr, command,
|
||||
(u8 *)&data->word,
|
||||
2, MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, 2, (u8 *)&data->word);
|
||||
break;
|
||||
case I2C_SMBUS_BLOCK_PROC_CALL:
|
||||
ret = mcp_smbus_write(mcp, addr, command, data->block,
|
||||
data->block[0] + 1,
|
||||
MCP2221_I2C_WR_NO_STOP, 0);
|
||||
if (ret)
|
||||
goto exit;
|
||||
|
||||
ret = mcp_i2c_smbus_read(mcp, NULL,
|
||||
MCP2221_I2C_RD_RPT_START,
|
||||
addr, I2C_SMBUS_BLOCK_MAX,
|
||||
data->block);
|
||||
break;
|
||||
default:
|
||||
dev_err(&mcp->adapter.dev,
|
||||
"unsupported smbus transaction size:%d\n", size);
|
||||
ret = -EOPNOTSUPP;
|
||||
}
|
||||
|
||||
exit:
|
||||
hid_hw_power(mcp->hdev, PM_HINT_NORMAL);
|
||||
mutex_unlock(&mcp->lock);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static u32 mcp_i2c_func(struct i2c_adapter *adapter)
|
||||
{
|
||||
return I2C_FUNC_I2C |
|
||||
I2C_FUNC_SMBUS_READ_BLOCK_DATA |
|
||||
I2C_FUNC_SMBUS_BLOCK_PROC_CALL |
|
||||
(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_PEC);
|
||||
}
|
||||
|
||||
static const struct i2c_algorithm mcp_i2c_algo = {
|
||||
.master_xfer = mcp_i2c_xfer,
|
||||
.smbus_xfer = mcp_smbus_xfer,
|
||||
.functionality = mcp_i2c_func,
|
||||
};
|
||||
|
||||
/* Gives current state of i2c engine inside mcp2221 */
|
||||
static int mcp_get_i2c_eng_state(struct mcp2221 *mcp,
|
||||
u8 *data, u8 idx)
|
||||
{
|
||||
int ret;
|
||||
|
||||
switch (data[idx]) {
|
||||
case MCP2221_I2C_WRADDRL_NACK:
|
||||
case MCP2221_I2C_WRADDRL_SEND:
|
||||
ret = -ENXIO;
|
||||
break;
|
||||
case MCP2221_I2C_START_TOUT:
|
||||
case MCP2221_I2C_STOP_TOUT:
|
||||
case MCP2221_I2C_WRADDRL_TOUT:
|
||||
case MCP2221_I2C_WRDATA_TOUT:
|
||||
ret = -ETIMEDOUT;
|
||||
break;
|
||||
case MCP2221_I2C_ENG_BUSY:
|
||||
ret = -EAGAIN;
|
||||
break;
|
||||
case MCP2221_SUCCESS:
|
||||
ret = 0x00;
|
||||
break;
|
||||
default:
|
||||
ret = -EIO;
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
/*
|
||||
* MCP2221 uses interrupt endpoint for input reports. This function
|
||||
* is called by HID layer when it receives i/p report from mcp2221,
|
||||
* which is actually a response to the previously sent command.
|
||||
*
|
||||
* MCP2221A firmware specific return codes are parsed and 0 or
|
||||
* appropriate negative error code is returned. Delayed response
|
||||
* results in timeout error and stray reponses results in -EIO.
|
||||
*/
|
||||
static int mcp2221_raw_event(struct hid_device *hdev,
|
||||
struct hid_report *report, u8 *data, int size)
|
||||
{
|
||||
u8 *buf;
|
||||
struct mcp2221 *mcp = hid_get_drvdata(hdev);
|
||||
|
||||
switch (data[0]) {
|
||||
|
||||
case MCP2221_I2C_WR_DATA:
|
||||
case MCP2221_I2C_WR_NO_STOP:
|
||||
case MCP2221_I2C_RD_DATA:
|
||||
case MCP2221_I2C_RD_RPT_START:
|
||||
switch (data[1]) {
|
||||
case MCP2221_SUCCESS:
|
||||
mcp->status = 0;
|
||||
break;
|
||||
default:
|
||||
mcp->status = mcp_get_i2c_eng_state(mcp, data, 2);
|
||||
}
|
||||
complete(&mcp->wait_in_report);
|
||||
break;
|
||||
|
||||
case MCP2221_I2C_PARAM_OR_STATUS:
|
||||
switch (data[1]) {
|
||||
case MCP2221_SUCCESS:
|
||||
if ((mcp->txbuf[3] == MCP2221_I2C_SET_SPEED) &&
|
||||
(data[3] != MCP2221_I2C_SET_SPEED)) {
|
||||
mcp->status = -EAGAIN;
|
||||
break;
|
||||
}
|
||||
if (data[20] & MCP2221_I2C_MASK_ADDR_NACK) {
|
||||
mcp->status = -ENXIO;
|
||||
break;
|
||||
}
|
||||
mcp->status = mcp_get_i2c_eng_state(mcp, data, 8);
|
||||
break;
|
||||
default:
|
||||
mcp->status = -EIO;
|
||||
}
|
||||
complete(&mcp->wait_in_report);
|
||||
break;
|
||||
|
||||
case MCP2221_I2C_GET_DATA:
|
||||
switch (data[1]) {
|
||||
case MCP2221_SUCCESS:
|
||||
if (data[2] == MCP2221_I2C_ADDR_NACK) {
|
||||
mcp->status = -ENXIO;
|
||||
break;
|
||||
}
|
||||
if (!mcp_get_i2c_eng_state(mcp, data, 2)
|
||||
&& (data[3] == 0)) {
|
||||
mcp->status = 0;
|
||||
break;
|
||||
}
|
||||
if (data[3] == 127) {
|
||||
mcp->status = -EIO;
|
||||
break;
|
||||
}
|
||||
if (data[2] == MCP2221_I2C_READ_COMPL) {
|
||||
buf = mcp->rxbuf;
|
||||
memcpy(&buf[mcp->rxbuf_idx], &data[4], data[3]);
|
||||
mcp->rxbuf_idx = mcp->rxbuf_idx + data[3];
|
||||
mcp->status = 0;
|
||||
break;
|
||||
}
|
||||
mcp->status = -EIO;
|
||||
break;
|
||||
default:
|
||||
mcp->status = -EIO;
|
||||
}
|
||||
complete(&mcp->wait_in_report);
|
||||
break;
|
||||
|
||||
default:
|
||||
mcp->status = -EIO;
|
||||
complete(&mcp->wait_in_report);
|
||||
}
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int mcp2221_probe(struct hid_device *hdev,
|
||||
const struct hid_device_id *id)
|
||||
{
|
||||
int ret;
|
||||
struct mcp2221 *mcp;
|
||||
|
||||
mcp = devm_kzalloc(&hdev->dev, sizeof(*mcp), GFP_KERNEL);
|
||||
if (!mcp)
|
||||
return -ENOMEM;
|
||||
|
||||
ret = hid_parse(hdev);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't parse reports\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't start hardware\n");
|
||||
return ret;
|
||||
}
|
||||
|
||||
ret = hid_hw_open(hdev);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't open device\n");
|
||||
goto err_hstop;
|
||||
}
|
||||
|
||||
mutex_init(&mcp->lock);
|
||||
init_completion(&mcp->wait_in_report);
|
||||
hid_set_drvdata(hdev, mcp);
|
||||
mcp->hdev = hdev;
|
||||
|
||||
/* Set I2C bus clock diviser */
|
||||
if (i2c_clk_freq > 400)
|
||||
i2c_clk_freq = 400;
|
||||
if (i2c_clk_freq < 50)
|
||||
i2c_clk_freq = 50;
|
||||
mcp->cur_i2c_clk_div = (12000000 / (i2c_clk_freq * 1000)) - 3;
|
||||
|
||||
mcp->adapter.owner = THIS_MODULE;
|
||||
mcp->adapter.class = I2C_CLASS_HWMON;
|
||||
mcp->adapter.algo = &mcp_i2c_algo;
|
||||
mcp->adapter.retries = 1;
|
||||
mcp->adapter.dev.parent = &hdev->dev;
|
||||
snprintf(mcp->adapter.name, sizeof(mcp->adapter.name),
|
||||
"MCP2221 usb-i2c bridge on hidraw%d",
|
||||
((struct hidraw *)hdev->hidraw)->minor);
|
||||
|
||||
ret = i2c_add_adapter(&mcp->adapter);
|
||||
if (ret) {
|
||||
hid_err(hdev, "can't add usb-i2c adapter: %d\n", ret);
|
||||
goto err_i2c;
|
||||
}
|
||||
i2c_set_adapdata(&mcp->adapter, mcp);
|
||||
|
||||
return 0;
|
||||
|
||||
err_i2c:
|
||||
hid_hw_close(mcp->hdev);
|
||||
err_hstop:
|
||||
hid_hw_stop(mcp->hdev);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void mcp2221_remove(struct hid_device *hdev)
|
||||
{
|
||||
struct mcp2221 *mcp = hid_get_drvdata(hdev);
|
||||
|
||||
i2c_del_adapter(&mcp->adapter);
|
||||
hid_hw_close(mcp->hdev);
|
||||
hid_hw_stop(mcp->hdev);
|
||||
}
|
||||
|
||||
static const struct hid_device_id mcp2221_devices[] = {
|
||||
{ HID_USB_DEVICE(USB_VENDOR_ID_MICROCHIP, USB_DEVICE_ID_MCP2221) },
|
||||
{ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(hid, mcp2221_devices);
|
||||
|
||||
static struct hid_driver mcp2221_driver = {
|
||||
.name = "mcp2221",
|
||||
.id_table = mcp2221_devices,
|
||||
.probe = mcp2221_probe,
|
||||
.remove = mcp2221_remove,
|
||||
.raw_event = mcp2221_raw_event,
|
||||
};
|
||||
|
||||
/* Register with HID core */
|
||||
module_hid_driver(mcp2221_driver);
|
||||
|
||||
MODULE_AUTHOR("Rishi Gupta <gupt21@gmail.com>");
|
||||
MODULE_DESCRIPTION("MCP2221 Microchip HID USB to I2C master bridge");
|
||||
MODULE_LICENSE("GPL v2");
|
Loading…
Reference in New Issue
Block a user