// SPDX-License-Identifier: GPL-2.0-only
/*
* hid-ft260.c - FTDI FT260 USB HID to I2C host bridge
*
* Copyright (c) 2021, Michael Zaidman <[email protected]>
*
* Data Sheet:
* https://www.ftdichip.com/Support/Documents/DataSheets/ICs/DS_FT260.pdf
*/
#include "hid-ids.h"
#include <linux/hidraw.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/usb.h>
#ifdef DEBUG
static int ft260_debug = 1;
#else
static int ft260_debug;
#endif
module_param_named(debug, ft260_debug, int, 0600);
MODULE_PARM_DESC(debug, "Toggle FT260 debugging messages");
#define ft260_dbg(format, arg...) \
do { \
if (ft260_debug) \
pr_info("%s: " format, __func__, ##arg); \
} while (0)
#define FT260_REPORT_MAX_LENGTH (64)
#define FT260_I2C_DATA_REPORT_ID(len) (FT260_I2C_REPORT_MIN + (len - 1) / 4)
#define FT260_WAKEUP_NEEDED_AFTER_MS (4800) /* 5s minus 200ms margin */
/*
* The ft260 input report format defines 62 bytes for the data payload, but
* when requested 62 bytes, the controller returns 60 and 2 in separate input
* reports. To achieve better performance with the multi-report read data
* transfers, we set the maximum read payload length to a multiple of 60.
* With a 100 kHz I2C clock, one 240 bytes read takes about 1/27 second,
* which is excessive; On the other hand, some higher layer drivers like at24
* or optoe limit the i2c reads to 128 bytes. To not block other drivers out
* of I2C for potentially troublesome amounts of time, we select the maximum
* read payload length to be 180 bytes.
*/
#define FT260_RD_DATA_MAX (180)
#define FT260_WR_DATA_MAX (60)
/*
* Device interface configuration.
* The FT260 has 2 interfaces that are controlled by DCNF0 and DCNF1 pins.
* First implementes USB HID to I2C bridge function and
* second - USB HID to UART bridge function.
*/
enum {
FT260_MODE_ALL = 0x00,
FT260_MODE_I2C = 0x01,
FT260_MODE_UART = 0x02,
FT260_MODE_BOTH = 0x03,
};
/* Control pipe */
enum {
FT260_GET_RQST_TYPE = 0xA1,
FT260_GET_REPORT = 0x01,
FT260_SET_RQST_TYPE = 0x21,
FT260_SET_REPORT = 0x09,
FT260_FEATURE = 0x03,
};
/* Report IDs / Feature In */
enum {
FT260_CHIP_VERSION = 0xA0,
FT260_SYSTEM_SETTINGS = 0xA1,
FT260_I2C_STATUS = 0xC0,
FT260_I2C_READ_REQ = 0xC2,
FT260_I2C_REPORT_MIN = 0xD0,
FT260_I2C_REPORT_MAX = 0xDE,
FT260_GPIO = 0xB0,
FT260_UART_INTERRUPT_STATUS = 0xB1,
FT260_UART_STATUS = 0xE0,
FT260_UART_RI_DCD_STATUS = 0xE1,
FT260_UART_REPORT = 0xF0,
};
/* Feature Out */
enum {
FT260_SET_CLOCK = 0x01,
FT260_SET_I2C_MODE = 0x02,
FT260_SET_UART_MODE = 0x03,
FT260_ENABLE_INTERRUPT = 0x05,
FT260_SELECT_GPIO2_FUNC = 0x06,
FT260_ENABLE_UART_DCD_RI = 0x07,
FT260_SELECT_GPIOA_FUNC = 0x08,
FT260_SELECT_GPIOG_FUNC = 0x09,
FT260_SET_INTERRUPT_TRIGGER = 0x0A,
FT260_SET_SUSPEND_OUT_POLAR = 0x0B,
FT260_ENABLE_UART_RI_WAKEUP = 0x0C,
FT260_SET_UART_RI_WAKEUP_CFG = 0x0D,
FT260_SET_I2C_RESET = 0x20,
FT260_SET_I2C_CLOCK_SPEED = 0x22,
FT260_SET_UART_RESET = 0x40,
FT260_SET_UART_CONFIG = 0x41,
FT260_SET_UART_BAUD_RATE = 0x42,
FT260_SET_UART_DATA_BIT = 0x43,
FT260_SET_UART_PARITY = 0x44,
FT260_SET_UART_STOP_BIT = 0x45,
FT260_SET_UART_BREAKING = 0x46,
FT260_SET_UART_XON_XOFF = 0x49,
};
/* Response codes in I2C status report */
enum {
FT260_I2C_STATUS_SUCCESS = 0x00,
FT260_I2C_STATUS_CTRL_BUSY = 0x01,
FT260_I2C_STATUS_ERROR = 0x02,
FT260_I2C_STATUS_ADDR_NO_ACK = 0x04,
FT260_I2C_STATUS_DATA_NO_ACK = 0x08,
FT260_I2C_STATUS_ARBITR_LOST = 0x10,
FT260_I2C_STATUS_CTRL_IDLE = 0x20,
FT260_I2C_STATUS_BUS_BUSY = 0x40,
};
/* I2C Conditions flags */
enum {
FT260_FLAG_NONE = 0x00,
FT260_FLAG_START = 0x02,
FT260_FLAG_START_REPEATED = 0x03,
FT260_FLAG_STOP = 0x04,
FT260_FLAG_START_STOP = 0x06,
FT260_FLAG_START_STOP_REPEATED = 0x07,
};
#define FT260_SET_REQUEST_VALUE(report_id) ((FT260_FEATURE << 8) | report_id)
/* Feature In reports */
struct ft260_get_chip_version_report {
u8 report; /* FT260_CHIP_VERSION */
u8 chip_code[4]; /* FTDI chip identification code */
u8 reserved[8];
} __packed;
struct ft260_get_system_status_report {
u8 report; /* FT260_SYSTEM_SETTINGS */
u8 chip_mode; /* DCNF0 and DCNF1 status, bits 0-1 */
u8 clock_ctl; /* 0 - 12MHz, 1 - 24MHz, 2 - 48MHz */
u8 suspend_status; /* 0 - not suspended, 1 - suspended */
u8 pwren_status; /* 0 - FT260 is not ready, 1 - ready */
u8 i2c_enable; /* 0 - disabled, 1 - enabled */
u8 uart_mode; /* 0 - OFF; 1 - RTS_CTS, 2 - DTR_DSR, */
/* 3 - XON_XOFF, 4 - No flow control */
u8 hid_over_i2c_en; /* 0 - disabled, 1 - enabled */
u8 gpio2_function; /* 0 - GPIO, 1 - SUSPOUT, */
/* 2 - PWREN, 4 - TX_LED */
u8 gpioA_function; /* 0 - GPIO, 3 - TX_ACTIVE, 4 - TX_LED */
u8 gpioG_function; /* 0 - GPIO, 2 - PWREN, */
/* 5 - RX_LED, 6 - BCD_DET */
u8 suspend_out_pol; /* 0 - active-high, 1 - active-low */
u8 enable_wakeup_int; /* 0 - disabled, 1 - enabled */
u8 intr_cond; /* Interrupt trigger conditions */
u8 power_saving_en; /* 0 - disabled, 1 - enabled */
u8 reserved[10];
} __packed;
struct ft260_get_i2c_status_report {
u8 report; /* FT260_I2C_STATUS */
u8 bus_status; /* I2C bus status */
__le16 clock; /* I2C bus clock in range 60-3400 KHz */
u8 reserved;
} __packed;
/* Feature Out reports */
struct ft260_set_system_clock_report {
u8 report; /* FT260_SYSTEM_SETTINGS */
u8 request; /* FT260_SET_CLOCK */
u8 clock_ctl; /* 0 - 12MHz, 1 - 24MHz, 2 - 48MHz */
} __packed;
struct ft260_set_i2c_mode_report {
u8 report; /* FT260_SYSTEM_SETTINGS */
u8 request; /* FT260_SET_I2C_MODE */
u8 i2c_enable; /* 0 - disabled, 1 - enabled */
} __packed;
struct ft260_set_uart_mode_report {
u8 report; /* FT260_SYSTEM_SETTINGS */
u8 request; /* FT260_SET_UART_MODE */
u8 uart_mode; /* 0 - OFF; 1 - RTS_CTS, 2 - DTR_DSR, */
/* 3 - XON_XOFF, 4 - No flow control */
} __packed;
struct ft260_set_i2c_reset_report {
u8 report; /* FT260_SYSTEM_SETTINGS */
u8 request; /* FT260_SET_I2C_RESET */
} __packed;
struct ft260_set_i2c_speed_report {
u8 report; /* FT260_SYSTEM_SETTINGS */
u8 request; /* FT260_SET_I2C_CLOCK_SPEED */
__le16 clock; /* I2C bus clock in range 60-3400 KHz */
} __packed;
/* Data transfer reports */
struct ft260_i2c_write_request_report {
u8 report; /* FT260_I2C_REPORT */
u8 address; /* 7-bit I2C address */
u8 flag; /* I2C transaction condition */
u8 length; /* data payload length */
u8 data[FT260_WR_DATA_MAX]; /* data payload */
} __packed;
struct ft260_i2c_read_request_report {
u8 report; /* FT260_I2C_READ_REQ */
u8 address; /* 7-bit I2C address */
u8 flag; /* I2C transaction condition */
__le16 length; /* data payload length */
} __packed;
struct ft260_i2c_input_report {
u8 report; /* FT260_I2C_REPORT */
u8 length; /* data payload length */
u8 data[2]; /* data payload */
} __packed;
static const struct hid_device_id ft260_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_FUTURE_TECHNOLOGY,
USB_DEVICE_ID_FT260) },
{ /* END OF LIST */ }
};
MODULE_DEVICE_TABLE(hid, ft260_devices);
struct ft260_device {
struct i2c_adapter adap;
struct hid_device *hdev;
struct completion wait;
struct mutex lock;
u8 write_buf[FT260_REPORT_MAX_LENGTH];
unsigned long need_wakeup_at;
u8 *read_buf;
u16 read_idx;
u16 read_len;
u16 clock;
};
static int ft260_hid_feature_report_get(struct hid_device *hdev,
unsigned char report_id, u8 *data,
size_t len)
{
u8 *buf;
int ret;
buf = kmalloc(len, GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = hid_hw_raw_request(hdev, report_id, buf, len, HID_FEATURE_REPORT,
HID_REQ_GET_REPORT);
if (likely(ret == len))
memcpy(data, buf, len);
else if (ret >= 0)
ret = -EIO;
kfree(buf);
return ret;
}
static int ft260_hid_feature_report_set(struct hid_device *hdev, u8 *data,
size_t len)
{
u8 *buf;
int ret;
buf = kmemdup(data, len, GFP_KERNEL);
if (!buf)
return -ENOMEM;
buf[0] = FT260_SYSTEM_SETTINGS;
ret = hid_hw_raw_request(hdev, buf[0], buf, len, HID_FEATURE_REPORT,
HID_REQ_SET_REPORT);
kfree(buf);
return ret;
}
static int ft260_i2c_reset(struct hid_device *hdev)
{
struct ft260_set_i2c_reset_report report;
int ret;
report.request = FT260_SET_I2C_RESET;
ret = ft260_hid_feature_report_set(hdev, (u8 *)&report, sizeof(report));
if (ret < 0) {
hid_err(hdev, "failed to reset I2C controller: %d\n", ret);
return ret;
}
ft260_dbg("done\n");
return ret;
}
static int ft260_xfer_status(struct ft260_device *dev, u8 bus_busy)
{
struct hid_device *hdev = dev->hdev;
struct ft260_get_i2c_status_report report;
int ret;
if (time_is_before_jiffies(dev->need_wakeup_at)) {
ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS,
(u8 *)&report, sizeof(report));
if (unlikely(ret < 0)) {
hid_err(hdev, "failed to retrieve status: %d, no wakeup\n",
ret);
} else {
dev->need_wakeup_at = jiffies +
msecs_to_jiffies(FT260_WAKEUP_NEEDED_AFTER_MS);
ft260_dbg("bus_status %#02x, wakeup\n",
report.bus_status);
}
}
ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS,
(u8 *)&report, sizeof(report));
if (unlikely(ret < 0)) {
hid_err(hdev, "failed to retrieve status: %d\n", ret);
return ret;
}
dev->clock = le16_to_cpu(report.clock);
ft260_dbg("bus_status %#02x, clock %u\n", report.bus_status,
dev->clock);
if (report.bus_status & (FT260_I2C_STATUS_CTRL_BUSY | bus_busy))
return -EAGAIN;
/*
* The error condition (bit 1) is a status bit reflecting any
* error conditions. When any of the bits 2, 3, or 4 are raised
* to 1, bit 1 is also set to 1.
*/
if (report.bus_status & FT260_I2C_STATUS_ERROR) {
hid_err(hdev, "i2c bus error: %#02x\n", report.bus_status);
return -EIO;
}
return 0;
}
static int ft260_hid_output_report(struct hid_device *hdev, u8 *data,
size_t len)
{
u8 *buf;
int ret;
buf = kmemdup(data, len, GFP_KERNEL);
if (!buf)
return -ENOMEM;
ret = hid_hw_output_report(hdev, buf, len);
kfree(buf);
return ret;
}
static int ft260_hid_output_report_check_status(struct ft260_device *dev,
u8 *data, int len)
{
u8 bus_busy;
int ret, usec, try = 100;
struct hid_device *hdev = dev->hdev;
struct ft260_i2c_write_request_report *rep =
(struct ft260_i2c_write_request_report *)data;
ret = ft260_hid_output_report(hdev, data, len);
if (ret < 0) {
hid_err(hdev, "%s: failed to start transfer, ret %d\n",
__func__, ret);
ft260_i2c_reset(hdev);
return ret;
}
/* transfer time = 1 / clock(KHz) * 9 bits * bytes */
usec = len * 9000 / dev->clock;
if (usec > 2000) {
usec -= 1500;
usleep_range(usec, usec + 100);
ft260_dbg("wait %d usec, len %d\n", usec, len);
}
/*
* Do not check the busy bit for combined transactions
* since the controller keeps the bus busy between writing
* and reading IOs to ensure an atomic operation.
*/
if (rep->flag == FT260_FLAG_START)
bus_busy = 0;
else
bus_busy = FT260_I2C_STATUS_BUS_BUSY;
do {
ret = ft260_xfer_status(dev, bus_busy);
if (ret != -EAGAIN)
break;
} while (--try);
if (ret == 0)
return 0;
ft260_i2c_reset(hdev);
return -EIO;
}
static int ft260_i2c_write(struct ft260_device *dev, u8 addr, u8 *data,
int len, u8 flag)
{
int ret, wr_len, idx = 0;
struct hid_device *hdev = dev->hdev;
struct ft260_i2c_write_request_report *rep =
(struct ft260_i2c_write_request_report *)dev->write_buf;
if (len < 1)
return -EINVAL;
rep->flag = FT260_FLAG_START;
do {
if (len <= FT260_WR_DATA_MAX) {
wr_len = len;
if (flag == FT260_FLAG_START_STOP)
rep->flag |= FT260_FLAG_STOP;
} else {
wr_len = FT260_WR_DATA_MAX;
}
rep->report = FT260_I2C_DATA_REPORT_ID(wr_len);
rep->address = addr;
rep->length = wr_len;
memcpy(rep->data, &data[idx], wr_len);
ft260_dbg("rep %#02x addr %#02x off %d len %d wlen %d flag %#x d[0] %#02x\n",
rep->report, addr, idx, len, wr_len,
rep->flag, data[0]);
ret = ft260_hid_output_report_check_status(dev, (u8 *)rep,
wr_len + 4);
if (ret < 0) {
hid_err(hdev, "%s: failed with %d\n", __func__, ret);
return ret;
}
len -= wr_len;
idx += wr_len;
rep->flag = 0;
} while (len > 0);
return 0;
}
static int ft260_smbus_write(struct ft260_device *dev, u8 addr, u8 cmd,
u8 *data, u8 data_len, u8 flag)
{
int ret = 0;
int len = 4;
struct ft260_i2c_write_request_report *rep =
(struct ft260_i2c_write_request_report *)dev->write_buf;
if (data_len >= sizeof(rep->data))
return -EINVAL;
rep->address = addr;
rep->data[0] = cmd;
rep->length = data_len + 1;
rep->flag = flag;
len += rep->length;
rep->report = FT260_I2C_DATA_REPORT_ID(len);
if (data_len > 0)
memcpy(&rep->data[1], data, data_len);
ft260_dbg("rep %#02x addr %#02x cmd %#02x datlen %d replen %d\n",
rep->report, addr, cmd, rep->length, len);
ret = ft260_hid_output_report_check_status(dev, (u8 *)rep, len);
return ret;
}
static int ft260_i2c_read(struct ft260_device *dev, u8 addr, u8 *data,
u16 len, u8 flag)
{
u16 rd_len;
u16 rd_data_max = 60;
int timeout, ret = 0;
struct ft260_i2c_read_request_report rep;
struct hid_device *hdev = dev->hdev;
u8 bus_busy = 0;
if ((flag & FT260_FLAG_START_REPEATED) == FT260_FLAG_START_REPEATED)
flag = FT260_FLAG_START_REPEATED;
else
flag = FT260_FLAG_START;
do {
if (len <= rd_data_max) {
rd_len = len;
flag |= FT260_FLAG_STOP;
} else {
rd_len = rd_data_max;
}
rd_data_max = FT260_RD_DATA_MAX;
rep.report = FT260_I2C_READ_REQ;
rep.length = cpu_to_le16(rd_len);
rep.address = addr;
rep.flag = flag;
ft260_dbg("rep %#02x addr %#02x len %d rlen %d flag %#x\n",
rep.report, rep.address, len, rd_len, flag);
reinit_completion(&dev->wait);
dev->read_idx = 0;
dev->read_buf = data;
dev->read_len = rd_len;
ret = ft260_hid_output_report(hdev, (u8 *)&rep, sizeof(rep));
if (ret < 0) {
hid_err(hdev, "%s: failed with %d\n", __func__, ret);
goto ft260_i2c_read_exit;
}
timeout = msecs_to_jiffies(5000);
if (!wait_for_completion_timeout(&dev->wait, timeout)) {
ret = -ETIMEDOUT;
ft260_i2c_reset(hdev);
goto ft260_i2c_read_exit;
}
dev->read_buf = NULL;
if (flag & FT260_FLAG_STOP)
bus_busy = FT260_I2C_STATUS_BUS_BUSY;
ret = ft260_xfer_status(dev, bus_busy);
if (ret < 0) {
ret = -EIO;
ft260_i2c_reset(hdev);
goto ft260_i2c_read_exit;
}
len -= rd_len;
data += rd_len;
flag = 0;
} while (len > 0);
ft260_i2c_read_exit:
dev->read_buf = NULL;
return ret;
}
/*
* A random read operation is implemented as a dummy write operation, followed
* by a current address read operation. The dummy write operation is used to
* load the target byte address into the current byte address counter, from
* which the subsequent current address read operation then reads.
*/
static int ft260_i2c_write_read(struct ft260_device *dev, struct i2c_msg *msgs)
{
int ret;
int wr_len = msgs[0].len;
int rd_len = msgs[1].len;
struct hid_device *hdev = dev->hdev;
u8 addr = msgs[0].addr;
u16 read_off = 0;
if (wr_len > 2) {
hid_err(hdev, "%s: invalid wr_len: %d\n", __func__, wr_len);
return -EOPNOTSUPP;
}
if (ft260_debug) {
if (wr_len == 2)
read_off = be16_to_cpu(*(__be16 *)msgs[0].buf);
else
read_off = *msgs[0].buf;
pr_info("%s: off %#x rlen %d wlen %d\n", __func__,
read_off, rd_len, wr_len);
}
ret = ft260_i2c_write(dev, addr, msgs[0].buf, wr_len,
FT260_FLAG_START);
if (ret < 0)
return ret;
ret = ft260_i2c_read(dev, addr, msgs[1].buf, rd_len,
FT260_FLAG_START_STOP_REPEATED);
if (ret < 0)
return ret;
return 0;
}
static int ft260_i2c_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs,
int num)
{
int ret;
struct ft260_device *dev = i2c_get_adapdata(adapter);
struct hid_device *hdev = dev->hdev;
mutex_lock(&dev->lock);
ret = hid_hw_power(hdev, PM_HINT_FULLON);
if (ret < 0) {
hid_err(hdev, "failed to enter FULLON power mode: %d\n", ret);
mutex_unlock(&dev->lock);
return ret;
}
if (num == 1) {
if (msgs->flags & I2C_M_RD)
ret = ft260_i2c_read(dev, msgs->addr, msgs->buf,
msgs->len, FT260_FLAG_START_STOP);
else
ret = ft260_i2c_write(dev, msgs->addr, msgs->buf,
msgs->len, FT260_FLAG_START_STOP);
if (ret < 0)
goto i2c_exit;
} else {
/* Combined write then read message */
ret = ft260_i2c_write_read(dev, msgs);
if (ret < 0)
goto i2c_exit;
}
ret = num;
i2c_exit:
hid_hw_power(hdev, PM_HINT_NORMAL);
mutex_unlock(&dev->lock);
return ret;
}
static int ft260_smbus_xfer(struct i2c_adapter *adapter, u16 addr, u16 flags,
char read_write, u8 cmd, int size,
union i2c_smbus_data *data)
{
int ret;
struct ft260_device *dev = i2c_get_adapdata(adapter);
struct hid_device *hdev = dev->hdev;
ft260_dbg("smbus size %d\n", size);
mutex_lock(&dev->lock);
ret = hid_hw_power(hdev, PM_HINT_FULLON);
if (ret < 0) {
hid_err(hdev, "power management error: %d\n", ret);
mutex_unlock(&dev->lock);
return ret;
}
switch (size) {
case I2C_SMBUS_BYTE:
if (read_write == I2C_SMBUS_READ)
ret = ft260_i2c_read(dev, addr, &data->byte, 1,
FT260_FLAG_START_STOP);
else
ret = ft260_smbus_write(dev, addr, cmd, NULL, 0,
FT260_FLAG_START_STOP);
break;
case I2C_SMBUS_BYTE_DATA:
if (read_write == I2C_SMBUS_READ) {
ret = ft260_smbus_write(dev, addr, cmd, NULL, 0,
FT260_FLAG_START);
if (ret)
goto smbus_exit;
ret = ft260_i2c_read(dev, addr, &data->byte, 1,
FT260_FLAG_START_STOP_REPEATED);
} else {
ret = ft260_smbus_write(dev, addr, cmd, &data->byte, 1,
FT260_FLAG_START_STOP);
}
break;
case I2C_SMBUS_WORD_DATA:
if (read_write == I2C_SMBUS_READ) {
ret = ft260_smbus_write(dev, addr, cmd, NULL, 0,
FT260_FLAG_START);
if (ret)
goto smbus_exit;
ret = ft260_i2c_read(dev, addr, (u8 *)&data->word, 2,
FT260_FLAG_START_STOP_REPEATED);
} else {
ret = ft260_smbus_write(dev, addr, cmd,
(u8 *)&data->word, 2,
FT260_FLAG_START_STOP);
}
break;
case I2C_SMBUS_BLOCK_DATA:
if (read_write == I2C_SMBUS_READ) {
ret = ft260_smbus_write(dev, addr, cmd, NULL, 0,
FT260_FLAG_START);
if (ret)
goto smbus_exit;
ret = ft260_i2c_read(dev, addr, data->block,
data->block[0] + 1,
FT260_FLAG_START_STOP_REPEATED);
} else {
ret = ft260_smbus_write(dev, addr, cmd, data->block,
data->block[0] + 1,
FT260_FLAG_START_STOP);
}
break;
case I2C_SMBUS_I2C_BLOCK_DATA:
if (read_write == I2C_SMBUS_READ) {
ret = ft260_smbus_write(dev, addr, cmd, NULL, 0,
FT260_FLAG_START);
if (ret)
goto smbus_exit;
ret = ft260_i2c_read(dev, addr, data->block + 1,
data->block[0],
FT260_FLAG_START_STOP_REPEATED);
} else {
ret = ft260_smbus_write(dev, addr, cmd, data->block + 1,
data->block[0],
FT260_FLAG_START_STOP);
}
break;
default:
hid_err(hdev, "unsupported smbus transaction size %d\n", size);
ret = -EOPNOTSUPP;
}
smbus_exit:
hid_hw_power(hdev, PM_HINT_NORMAL);
mutex_unlock(&dev->lock);
return ret;
}
static u32 ft260_functionality(struct i2c_adapter *adap)
{
return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE |
I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_I2C_BLOCK;
}
static const struct i2c_adapter_quirks ft260_i2c_quirks = {
.flags = I2C_AQ_COMB_WRITE_THEN_READ,
.max_comb_1st_msg_len = 2,
};
static const struct i2c_algorithm ft260_i2c_algo = {
.master_xfer = ft260_i2c_xfer,
.smbus_xfer = ft260_smbus_xfer,
.functionality = ft260_functionality,
};
static int ft260_get_system_config(struct hid_device *hdev,
struct ft260_get_system_status_report *cfg)
{
int ret;
int len = sizeof(struct ft260_get_system_status_report);
ret = ft260_hid_feature_report_get(hdev, FT260_SYSTEM_SETTINGS,
(u8 *)cfg, len);
if (ret < 0) {
hid_err(hdev, "failed to retrieve system status\n");
return ret;
}
return 0;
}
static int ft260_is_interface_enabled(struct hid_device *hdev)
{
struct ft260_get_system_status_report cfg;
struct usb_interface *usbif = to_usb_interface(hdev->dev.parent);
int interface = usbif->cur_altsetting->desc.bInterfaceNumber;
int ret;
ret = ft260_get_system_config(hdev, &cfg);
if (ret < 0)
return ret;
ft260_dbg("interface: 0x%02x\n", interface);
ft260_dbg("chip mode: 0x%02x\n", cfg.chip_mode);
ft260_dbg("clock_ctl: 0x%02x\n", cfg.clock_ctl);
ft260_dbg("i2c_enable: 0x%02x\n", cfg.i2c_enable);
ft260_dbg("uart_mode: 0x%02x\n", cfg.uart_mode);
switch (cfg.chip_mode) {
case FT260_MODE_ALL:
case FT260_MODE_BOTH:
if (interface == 1)
hid_info(hdev, "uart interface is not supported\n");
else
ret = 1;
break;
case FT260_MODE_UART:
hid_info(hdev, "uart interface is not supported\n");
break;
case FT260_MODE_I2C:
ret = 1;
break;
}
return ret;
}
static int ft260_byte_show(struct hid_device *hdev, int id, u8 *cfg, int len,
u8 *field, u8 *buf)
{
int ret;
ret = ft260_hid_feature_report_get(hdev, id, cfg, len);
if (ret < 0)
return ret;
return scnprintf(buf, PAGE_SIZE, "%d\n", *field);
}
static int ft260_word_show(struct hid_device *hdev, int id, u8 *cfg, int len,
__le16 *field, u8 *buf)
{
int ret;
ret = ft260_hid_feature_report_get(hdev, id, cfg, len);
if (ret < 0)
return ret;
return scnprintf(buf, PAGE_SIZE, "%d\n", le16_to_cpu(*field));
}
#define FT260_ATTR_SHOW(name, reptype, id, type, func) \
static ssize_t name##_show(struct device *kdev, \
struct device_attribute *attr, char *buf) \
{ \
struct reptype rep; \
struct hid_device *hdev = to_hid_device(kdev); \
type *field = &rep.name; \
int len = sizeof(rep); \
\
return func(hdev, id, (u8 *)&rep, len, field, buf); \
}
#define FT260_SSTAT_ATTR_SHOW(name) \
FT260_ATTR_SHOW(name, ft260_get_system_status_report, \
FT260_SYSTEM_SETTINGS, u8, ft260_byte_show)
#define FT260_I2CST_ATTR_SHOW(name) \
FT260_ATTR_SHOW(name, ft260_get_i2c_status_report, \
FT260_I2C_STATUS, __le16, ft260_word_show)
#define FT260_ATTR_STORE(name, reptype, id, req, type, ctype, func) \
static ssize_t name##_store(struct device *kdev, \
struct device_attribute *attr, \
const char *buf, size_t count) \
{ \
struct reptype rep; \
struct hid_device *hdev = to_hid_device(kdev); \
type name; \
int ret; \
\
if (!func(buf, 10, (ctype *)&name)) { \
rep.name = name; \
rep.report = id; \
rep.request = req; \
ret = ft260_hid_feature_report_set(hdev, (u8 *)&rep, \
sizeof(rep)); \
if (!ret) \
ret = count; \
} else { \
ret = -EINVAL; \
} \
return ret; \
}
#define FT260_BYTE_ATTR_STORE(name, reptype, req) \
FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \
u8, u8, kstrtou8)
#define FT260_WORD_ATTR_STORE(name, reptype, req) \
FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \
__le16, u16, kstrtou16)
FT260_SSTAT_ATTR_SHOW(chip_mode);
static DEVICE_ATTR_RO(chip_mode);
FT260_SSTAT_ATTR_SHOW(pwren_status);
static DEVICE_ATTR_RO(pwren_status);
FT260_SSTAT_ATTR_SHOW(suspend_status);
static DEVICE_ATTR_RO(suspend_status);
FT260_SSTAT_ATTR_SHOW(hid_over_i2c_en);
static DEVICE_ATTR_RO(hid_over_i2c_en);
FT260_SSTAT_ATTR_SHOW(power_saving_en);
static DEVICE_ATTR_RO(power_saving_en);
FT260_SSTAT_ATTR_SHOW(i2c_enable);
FT260_BYTE_ATTR_STORE(i2c_enable, ft260_set_i2c_mode_report,
FT260_SET_I2C_MODE);
static DEVICE_ATTR_RW(i2c_enable);
FT260_SSTAT_ATTR_SHOW(uart_mode);
FT260_BYTE_ATTR_STORE(uart_mode, ft260_set_uart_mode_report,
FT260_SET_UART_MODE);
static DEVICE_ATTR_RW(uart_mode);
FT260_SSTAT_ATTR_SHOW(clock_ctl);
FT260_BYTE_ATTR_STORE(clock_ctl, ft260_set_system_clock_report,
FT260_SET_CLOCK);
static DEVICE_ATTR_RW(clock_ctl);
FT260_I2CST_ATTR_SHOW(clock);
FT260_WORD_ATTR_STORE(clock, ft260_set_i2c_speed_report,
FT260_SET_I2C_CLOCK_SPEED);
static DEVICE_ATTR_RW(clock);
static ssize_t i2c_reset_store(struct device *kdev,
struct device_attribute *attr, const char *buf,
size_t count)
{
struct hid_device *hdev = to_hid_device(kdev);
int ret = ft260_i2c_reset(hdev);
if (ret)
return ret;
return count;
}
static DEVICE_ATTR_WO(i2c_reset);
static const struct attribute_group ft260_attr_group = {
.attrs = (struct attribute *[]) {
&dev_attr_chip_mode.attr,
&dev_attr_pwren_status.attr,
&dev_attr_suspend_status.attr,
&dev_attr_hid_over_i2c_en.attr,
&dev_attr_power_saving_en.attr,
&dev_attr_i2c_enable.attr,
&dev_attr_uart_mode.attr,
&dev_attr_clock_ctl.attr,
&dev_attr_i2c_reset.attr,
&dev_attr_clock.attr,
NULL
}
};
static int ft260_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
struct ft260_device *dev;
struct ft260_get_chip_version_report version;
int ret;
if (!hid_is_usb(hdev))
return -EINVAL;
dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
ret = hid_parse(hdev);
if (ret) {
hid_err(hdev, "failed to parse HID\n");
return ret;
}
ret = hid_hw_start(hdev, 0);
if (ret) {
hid_err(hdev, "failed to start HID HW\n");
return ret;
}
ret = hid_hw_open(hdev);
if (ret) {
hid_err(hdev, "failed to open HID HW\n");
goto err_hid_stop;
}
ret = ft260_hid_feature_report_get(hdev, FT260_CHIP_VERSION,
(u8 *)&version, sizeof(version));
if (ret < 0) {
hid_err(hdev, "failed to retrieve chip version\n");
goto err_hid_close;
}
hid_info(hdev, "chip code: %02x%02x %02x%02x\n",
version.chip_code[0], version.chip_code[1],
version.chip_code[2], version.chip_code[3]);
ret = ft260_is_interface_enabled(hdev);
if (ret <= 0)
goto err_hid_close;
hid_info(hdev, "USB HID v%x.%02x Device [%s] on %s\n",
hdev->version >> 8, hdev->version & 0xff, hdev->name,
hdev->phys);
hid_set_drvdata(hdev, dev);
dev->hdev = hdev;
dev->adap.owner = THIS_MODULE;
dev->adap.class = I2C_CLASS_HWMON;
dev->adap.algo = &ft260_i2c_algo;
dev->adap.quirks = &ft260_i2c_quirks;
dev->adap.dev.parent = &hdev->dev;
snprintf(dev->adap.name, sizeof(dev->adap.name),
"FT260 usb-i2c bridge");
mutex_init(&dev->lock);
init_completion(&dev->wait);
ret = ft260_xfer_status(dev, FT260_I2C_STATUS_BUS_BUSY);
if (ret)
ft260_i2c_reset(hdev);
i2c_set_adapdata(&dev->adap, dev);
ret = i2c_add_adapter(&dev->adap);
if (ret) {
hid_err(hdev, "failed to add i2c adapter\n");
goto err_hid_close;
}
ret = sysfs_create_group(&hdev->dev.kobj, &ft260_attr_group);
if (ret < 0) {
hid_err(hdev, "failed to create sysfs attrs\n");
goto err_i2c_free;
}
return 0;
err_i2c_free:
i2c_del_adapter(&dev->adap);
err_hid_close:
hid_hw_close(hdev);
err_hid_stop:
hid_hw_stop(hdev);
return ret;
}
static void ft260_remove(struct hid_device *hdev)
{
struct ft260_device *dev = hid_get_drvdata(hdev);
if (!dev)
return;
sysfs_remove_group(&hdev->dev.kobj, &ft260_attr_group);
i2c_del_adapter(&dev->adap);
hid_hw_close(hdev);
hid_hw_stop(hdev);
}
static int ft260_raw_event(struct hid_device *hdev, struct hid_report *report,
u8 *data, int size)
{
struct ft260_device *dev = hid_get_drvdata(hdev);
struct ft260_i2c_input_report *xfer = (void *)data;
if (xfer->report >= FT260_I2C_REPORT_MIN &&
xfer->report <= FT260_I2C_REPORT_MAX) {
ft260_dbg("i2c resp: rep %#02x len %d\n", xfer->report,
xfer->length);
if ((dev->read_buf == NULL) ||
(xfer->length > dev->read_len - dev->read_idx)) {
hid_err(hdev, "unexpected report %#02x, length %d\n",
xfer->report, xfer->length);
return -1;
}
memcpy(&dev->read_buf[dev->read_idx], &xfer->data,
xfer->length);
dev->read_idx += xfer->length;
if (dev->read_idx == dev->read_len)
complete(&dev->wait);
} else {
hid_err(hdev, "unhandled report %#02x\n", xfer->report);
}
return 0;
}
static struct hid_driver ft260_driver = {
.name = "ft260",
.id_table = ft260_devices,
.probe = ft260_probe,
.remove = ft260_remove,
.raw_event = ft260_raw_event,
};
module_hid_driver(ft260_driver);
MODULE_DESCRIPTION("FTDI FT260 USB HID to I2C host bridge");
MODULE_AUTHOR("Michael Zaidman <[email protected]>");
MODULE_LICENSE("GPL v2");
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