The FT260 is a USB device that implements USB to I2C/UART bridges
through two USB HID class interfaces. The first - for I2C, and the
second for UART. Each interface is independent, and the kernel
detects it as a separate hidraw device.
This commit adds I2C host adapter support, enabling a wide range of
standard userspace tools and applications that do not implement HID
protocol, to access the I2C client devices via FT260 I2C controller.
The driver was tested with different I2C client devices, Linux
kernels, and Linux userspace tools.
For data transfer, the FT260 implements one Interrupt IN and one
Interrupt OUT pipes per interface. For configuration and control,
the FT260 exposes the HID class commands through the Control pipe.
Commands and responses are FT260 specific and documented in the
AN_394_User_Guide_for_FT260.pdf on the https://www.ftdichip.com.
Michael Zaidman (1):
HID: ft260: add usb hid to i2c host bridge driver
MAINTAINERS | 7 +
drivers/hid/Kconfig | 11 +
drivers/hid/Makefile | 2 +
drivers/hid/hid-ft260.c | 1097 +++++++++++++++++++++++++++++++++++++++
drivers/hid/hid-ids.h | 1 +
5 files changed, 1118 insertions(+)
create mode 100644 drivers/hid/hid-ft260.c
base-commit: 07f7e57c63aaa2afb4ea31edef05e08699a63a00
--
2.25.1
The FT260 is a USB device that implements USB to I2C/UART bridges
through two USB HID class interfaces. The first - for I2C, and the
second for UART. Each interface is independently controlled, and
the kernel detects each interface as a separate hidraw device.
This commit adds I2C host adapter support.
Signed-off-by: Michael Zaidman <[email protected]>
---
MAINTAINERS | 7 +
drivers/hid/Kconfig | 11 +
drivers/hid/Makefile | 2 +
drivers/hid/hid-ft260.c | 1097 +++++++++++++++++++++++++++++++++++++++
drivers/hid/hid-ids.h | 1 +
5 files changed, 1118 insertions(+)
create mode 100644 drivers/hid/hid-ft260.c
diff --git a/MAINTAINERS b/MAINTAINERS
index c38651ca59a5..69f7405b5cdb 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7310,6 +7310,13 @@ F: fs/verity/
F: include/linux/fsverity.h
F: include/uapi/linux/fsverity.h
+FT260 FTDI USB-HID TO I2C BRIDGE DRIVER
+M: Michael Zaidman <[email protected]>
+L: [email protected]
+L: [email protected]
+S: Maintained
+F: drivers/hid/hid-ft260.c
+
FUJITSU LAPTOP EXTRAS
M: Jonathan Woithe <[email protected]>
L: [email protected]
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index a7dcbda74221..837d99e8f1f5 100644
--- a/drivers/hid/Kconfig
+++ b/drivers/hid/Kconfig
@@ -351,6 +351,17 @@ config HID_EZKEY
help
Support for Ezkey BTC 8193 keyboard.
+config HID_FT260
+ tristate "FTDI FT260 USB HID to I2C host support"
+ depends on USB_HID && HIDRAW && I2C
+ help
+ Provides I2C host adapter functionality over USB-HID through FT260
+ device. The customizable USB descriptor fields are exposed as sysfs
+ attributes.
+
+ To compile this driver as a module, choose M here: the module
+ will be called hid-ft260.
+
config HID_GEMBIRD
tristate "Gembird Joypad"
depends on HID
diff --git a/drivers/hid/Makefile b/drivers/hid/Makefile
index c4f6d5c613dc..b6fbc19e7c7c 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -145,3 +145,5 @@ obj-$(CONFIG_INTEL_ISH_HID) += intel-ish-hid/
obj-$(INTEL_ISH_FIRMWARE_DOWNLOADER) += intel-ish-hid/
obj-$(CONFIG_AMD_SFH_HID) += amd-sfh-hid/
+
+obj-$(CONFIG_HID_FT260) += hid-ft260.o
diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c
new file mode 100644
index 000000000000..47481aeaadd3
--- /dev/null
+++ b/drivers/hid/hid-ft260.c
@@ -0,0 +1,1097 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * hid-ft260.c - FTDI 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)
+/*
+ * The input report format assigns 62 bytes for the data payload, but ft260
+ * returns 60 and 2 in two separate transactions. To minimize transfer time
+ * in reading chunks mode, set the maximum read payload length to 60 bytes.
+ */
+#define FT260_RD_DATA_MAX (60)
+#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_POLARITY = 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_CONTROLLER_BUSY = 0x01,
+ FT260_I2C_STATUS_ERROR = 0x02,
+ FT260_I2C_STATUS_ADDR_NO_ACK = 0x04,
+ FT260_I2C_STATUS_DATA_NO_ACK = 0x08,
+ FT260_I2C_STATUS_ARBITRATION_LOST = 0x10,
+ FT260_I2C_STATUS_CONTROLLER_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_REPEATED_START_STOP = 0x07,
+};
+
+#define FT260_SET_REQUEST_VALUE(report_id) ((FT260_FEATURE << 8) | report_id)
+
+struct ft260_request_report {
+ u8 request_type; /* FT260_GET_RQST_TYPE / FT260_SET_RQST_TYPE */
+ u8 request; /* FT260_GET_REPORT / FT260_SET_REPORT */
+ __le16 value; /* (FT260_FEATURE << 8) | report ID */
+ __le16 interface;
+ __le16 length;
+} __packed;
+
+/* 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 address of the I2C slave device */
+ u8 flag; /* I2C condition to send with transaction */
+ u8 length; /* data payload length */
+ u8 data[60]; /* data payload */
+} __packed;
+
+struct ft260_i2c_read_request_report {
+ u8 report; /* FT260_I2C_READ_REQ */
+ u8 address; /* 7-bit address of the I2C slave device */
+ u8 flag; /* I2C condition to send with transaction */
+ __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];
+ u8 *read_buf;
+ u16 read_idx;
+ u16 read_len;
+ u16 clock;
+ u8 read_chunks;
+};
+
+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);
+ memcpy(data, buf, len);
+ 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)
+{
+ struct hid_device *hdev = dev->hdev;
+ struct ft260_get_i2c_status_report report;
+ int ret;
+
+ ret = ft260_hid_feature_report_get(hdev, FT260_I2C_STATUS,
+ (u8 *)&report, sizeof(report));
+ if (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_CONTROLLER_BUSY) {
+ ft260_dbg("controller busy\n");
+ return -EAGAIN;
+ }
+
+ if (report.bus_status & FT260_I2C_STATUS_BUS_BUSY) {
+ ft260_dbg("i2c bus busy\n");
+ return -EBUSY;
+ }
+
+ if (report.bus_status & FT260_I2C_STATUS_ERROR) {
+ ft260_dbg("error condition\n");
+ return -EIO;
+ }
+
+ ret = -EIO;
+
+ if (report.bus_status & FT260_I2C_STATUS_ADDR_NO_ACK)
+ ft260_dbg("slave address was not acknowledged during last\n");
+
+ if (report.bus_status & FT260_I2C_STATUS_DATA_NO_ACK)
+ ft260_dbg("data not acknowledged during last operation\n");
+
+ if (report.bus_status & FT260_I2C_STATUS_ARBITRATION_LOST)
+ ft260_dbg("arbitration lost during last operation\n");
+
+ if (report.bus_status & FT260_I2C_STATUS_CONTROLLER_IDLE)
+ ret = 0;
+
+ return ret;
+}
+
+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)
+{
+ int ret, usec, try = 3;
+ struct hid_device *hdev = dev->hdev;
+
+ ret = ft260_hid_output_report(hdev, data, len);
+ if (ret < 0) {
+ hid_err(hdev, "failed to start transfer: %d\n", ret);
+ ft260_i2c_reset(hdev);
+ return ret;
+ }
+
+ /* transfer time = 1 / clock(KHz) * 10 bits * bytes */
+ usec = 10000 / dev->clock * len;
+ usleep_range(usec, usec + 100);
+ ft260_dbg("wait %d usec, len %d\n", usec, len);
+ do {
+ ret = ft260_xfer_status(dev);
+ if (ret != -EAGAIN)
+ break;
+ } while (--try);
+
+ if (ret == 0 || ret == -EBUSY)
+ return 0;
+
+ ft260_i2c_reset(hdev);
+ return -EIO;
+}
+
+static int ft260_i2c_write(struct ft260_device *dev, u8 addr, u8 *data,
+ u8 data_len, u8 flag)
+{
+ int len, ret, idx = 0;
+ struct hid_device *hdev = dev->hdev;
+ struct ft260_i2c_write_request_report *rep =
+ (struct ft260_i2c_write_request_report *)dev->write_buf;
+
+ do {
+ if (data_len <= FT260_WR_DATA_MAX)
+ len = data_len;
+ else
+ len = FT260_WR_DATA_MAX;
+
+ rep->report = FT260_I2C_DATA_REPORT_ID(len);
+ rep->address = addr;
+ rep->length = len;
+ rep->flag = flag;
+
+ ft260_dbg(
+ "report %#02x addr %#02x off %d len %d d[0] %#02x d[1] %#02x\n",
+ rep->report, addr, idx, len, data[0], data[1]);
+
+ memcpy(rep->data, &data[idx], len);
+
+ ret = ft260_hid_output_report_check_status(dev, (u8 *)rep,
+ len + 4);
+ if (ret < 0) {
+ hid_err(hdev, "%s: failed to start transfer, ret %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ data_len -= len;
+ idx += len;
+
+ } while (data_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;
+
+ rep->address = addr;
+ rep->flag = flag;
+ rep->data[0] = cmd;
+ rep->length = data_len + 1;
+ len += rep->length;
+
+ rep->report = FT260_I2C_DATA_REPORT_ID(len);
+
+ if (data_len > 0) {
+ memcpy(&rep->data[1], data, data_len);
+ ft260_dbg("report %#02x addr %#02x cmd %#02x datlen %d replen %d d[0] %#02x\n",
+ rep->report, addr, cmd, rep->length, len, data[0]);
+ } else {
+ ft260_dbg("report %#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 data_len, u8 flag)
+{
+ struct ft260_i2c_read_request_report rep;
+ struct hid_device *hdev = dev->hdev;
+ int timeout;
+ int ret;
+
+ if (data_len > FT260_RD_DATA_MAX) {
+ ft260_dbg("invalid read data_len %d\n", data_len);
+ return -EINVAL;
+ }
+
+ dev->read_idx = 0;
+ dev->read_buf = data;
+ dev->read_len = data_len;
+
+ rep.report = FT260_I2C_READ_REQ;
+ rep.address = addr;
+ rep.length = cpu_to_le16(data_len);
+ rep.flag = flag;
+
+ ft260_dbg("report %#02x addr %#02x len %d\n", rep.report, rep.address,
+ rep.length);
+
+ reinit_completion(&dev->wait);
+
+ ret = ft260_hid_output_report(hdev, (u8 *)&rep, sizeof(rep));
+ if (ret < 0) {
+ hid_err(hdev, "%s: failed to start transaction, ret %d\n",
+ __func__, ret);
+ return ret;
+ }
+
+ timeout = msecs_to_jiffies(5000);
+ if (!wait_for_completion_timeout(&dev->wait, timeout)) {
+ ft260_i2c_reset(hdev);
+ return -ETIMEDOUT;
+ }
+
+ ret = ft260_xfer_status(dev);
+ if (ret == 0)
+ return 0;
+
+ ft260_i2c_reset(hdev);
+ return -EIO;
+}
+
+/*
+ * 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;
+
+ ret = ft260_i2c_write(dev, msgs[0].addr, msgs[0].buf, msgs[0].len,
+ FT260_FLAG_START);
+ if (ret < 0)
+ return ret;
+
+ ret = ft260_i2c_read(dev, msgs[1].addr, msgs[1].buf, msgs[1].len,
+ FT260_FLAG_START_STOP);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int ft260_i2c_write_read_chunks(struct ft260_device *dev,
+ struct i2c_msg *msgs)
+{
+ int len, ret;
+ u16 left_len = msgs[1].len;
+ u8 *read_buf = msgs[1].buf;
+ u8 addr = msgs[0].addr;
+ u16 read_off = 0;
+ struct hid_device *hdev = dev->hdev;
+
+ if (msgs[0].len > 2) {
+ hid_err(hdev, "%s: unsupported len: %d\n", __func__, len);
+ return -EOPNOTSUPP;
+ }
+
+ memcpy(&read_off, msgs[0].buf, msgs[0].len);
+
+ do {
+ if (left_len <= FT260_RD_DATA_MAX)
+ len = left_len;
+ else
+ len = FT260_RD_DATA_MAX;
+
+ ft260_dbg("read_off %#x left_len %d len %d\n", read_off,
+ left_len, len);
+
+ ret = ft260_i2c_write(dev, addr, (u8 *)&read_off, msgs[0].len,
+ FT260_FLAG_START);
+ if (ret < 0)
+ return ret;
+
+ ret = ft260_i2c_read(dev, addr, read_buf, len,
+ FT260_FLAG_START_STOP);
+ if (ret < 0)
+ return ret;
+
+ left_len -= len;
+ read_buf += len;
+ read_off += len;
+
+ } while (left_len > 0);
+
+ 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) {
+ ft260_dbg("i2c rd: %#04x len %d\n", msgs->addr,
+ msgs->len);
+ ret = ft260_i2c_read(dev, msgs->addr, msgs->buf,
+ msgs->len, FT260_FLAG_START_STOP);
+ } else {
+ ft260_dbg("i2c wr: %#04x len %d\n", msgs->addr,
+ msgs->len);
+ 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 */
+ ft260_dbg("i2c combined: addr %#04x wr_len %d rd_len %d\n",
+ msgs[0].addr, msgs[0].len, msgs[1].len);
+
+ if (dev->read_chunks)
+ ret = ft260_i2c_write_read_chunks(dev, msgs);
+ else
+ 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);
+ ft260_dbg("transfer ret: %d\n", ret);
+ 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_QUICK:
+ if (read_write == I2C_SMBUS_READ)
+ ret = ft260_i2c_read(dev, addr, &data->byte, 0,
+ FT260_FLAG_START_STOP);
+ else
+ ret = ft260_smbus_write(dev, addr, cmd, NULL, 0,
+ FT260_FLAG_START_STOP);
+ break;
+ 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_REPEATED_START_STOP);
+ } 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_REPEATED_START_STOP);
+ } 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_REPEATED_START_STOP);
+ } 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_REPEATED_START_STOP);
+ } 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);
+ ft260_dbg("transfer ret: %d\n", ret);
+ return ret;
+}
+
+static u32 ft260_functionality(struct i2c_adapter *adap)
+{
+ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE | I2C_FUNC_SMBUS_QUICK |
+ 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 != len) {
+ hid_err(hdev, "failed to retrieve system status\n");
+ if (ret >= 0)
+ return -EIO;
+ }
+ 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)
+ 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");
+ return 0;
+ }
+ ret = 1;
+ break;
+ case FT260_MODE_UART:
+ if (interface == 0) {
+ hid_info(hdev, "uart is unsupported on interface 0\n");
+ ret = 0;
+ }
+ break;
+ case FT260_MODE_I2C:
+ if (interface == 1) {
+ hid_info(hdev, "i2c is unsupported on interface 1\n");
+ ret = 0;
+ }
+ 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 != len && ret >= 0)
+ return -EIO;
+
+ return scnprintf(buf, PAGE_SIZE, "%hi\n", *field);
+}
+
+static int ft260_word_show(struct hid_device *hdev, int id, u8 *cfg, int len,
+ u16 *field, u8 *buf)
+{
+ int ret;
+
+ ret = ft260_hid_feature_report_get(hdev, id, cfg, len);
+ if (ret != len && ret >= 0)
+ return -EIO;
+
+ return scnprintf(buf, PAGE_SIZE, "%hi\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, u16, ft260_word_show)
+
+#define FT260_ATTR_STORE(name, reptype, id, req, type, 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, &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, kstrtou8)
+
+#define FT260_WORD_ATTR_STORE(name, reptype, req) \
+ FT260_ATTR_STORE(name, reptype, FT260_SYSTEM_SETTINGS, req, \
+ 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;
+
+ 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, HID_CONNECT_HIDRAW);
+ 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 != sizeof(version)) {
+ hid_err(hdev, "failed to retrieve chip version\n");
+ if (ret >= 0)
+ ret = -EIO;
+ 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_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 on hidraw%d",
+ ((struct hidraw *)hdev->hidraw)->minor);
+
+ dev->read_chunks = 1;
+
+ mutex_init(&dev->lock);
+ init_completion(&dev->wait);
+
+ ret = i2c_add_adapter(&dev->adap);
+ if (ret) {
+ hid_err(hdev, "failed to add i2c adapter\n");
+ goto err_hid_close;
+ }
+
+ i2c_set_adapdata(&dev->adap, dev);
+
+ 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;
+ }
+
+ ret = ft260_xfer_status(dev);
+ if (ret)
+ ft260_i2c_reset(hdev);
+
+ 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)
+{
+ int ret;
+ struct ft260_device *dev = hid_get_drvdata(hdev);
+
+ ret = ft260_is_interface_enabled(hdev);
+ if (ret <= 0)
+ 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;
+
+ ft260_dbg("i2c report %#02x\n", xfer->report);
+
+ if (xfer->report >= FT260_I2C_REPORT_MIN &&
+ xfer->report <= FT260_I2C_REPORT_MAX) {
+ /* Read response in one of the input reports */
+ ft260_dbg("read response: len %d d[0] %#02x\n", xfer->length,
+ xfer->data[0]);
+
+ 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, "unknown report: %d\n", xfer->report);
+ return 0;
+ }
+ return 1;
+}
+
+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 USB HID to I2C host bridge");
+MODULE_AUTHOR("Michael Zaidman <[email protected]>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
index e42aaae3138f..daa4c0318cbc 100644
--- a/drivers/hid/hid-ids.h
+++ b/drivers/hid/hid-ids.h
@@ -430,6 +430,7 @@
#define USB_VENDOR_ID_FUTURE_TECHNOLOGY 0x0403
#define USB_DEVICE_ID_RETRODE2 0x97c1
+#define USB_DEVICE_ID_FT260 0x6030
#define USB_VENDOR_ID_ESSENTIAL_REALITY 0x0d7f
#define USB_DEVICE_ID_ESSENTIAL_REALITY_P5 0x0100
--
2.25.1