[PATCH v2 1/1] HID: ft260: add usb hid to i2c host bridge driver
From: Michael Zaidman
Date: Fri Feb 19 2021 - 11:38:40 EST
The FTDI FT260 chip 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
USB hidraw device.
This commit adds I2C host adapter support.
Signed-off-by: Michael Zaidman <michael.zaidman@xxxxxxxxx>
---
MAINTAINERS | 7 +
drivers/hid/Kconfig | 11 +
drivers/hid/Makefile | 1 +
drivers/hid/hid-ft260.c | 1053 +++++++++++++++++++++++++++++++++++++++
drivers/hid/hid-ids.h | 1 +
5 files changed, 1073 insertions(+)
create mode 100644 drivers/hid/hid-ft260.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 8a6fe5389d7d..30526cfd4994 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -7328,6 +7328,13 @@ 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 <michael.zaidman@xxxxxxxxx>
+L: linux-i2c@xxxxxxxxxxxxxxx
+L: linux-input@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/hid/hid-ft260.c
+
FUJITSU LAPTOP EXTRAS
M: Jonathan Woithe <jwoithe@xxxxxxxxxx>
L: platform-driver-x86@xxxxxxxxxxxxxxx
diff --git a/drivers/hid/Kconfig b/drivers/hid/Kconfig
index 786b71ef7738..b279c6130bc2 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..6e24c37132ec 100644
--- a/drivers/hid/Makefile
+++ b/drivers/hid/Makefile
@@ -46,6 +46,7 @@ obj-$(CONFIG_HID_ELAN) += hid-elan.o
obj-$(CONFIG_HID_ELECOM) += hid-elecom.o
obj-$(CONFIG_HID_ELO) += hid-elo.o
obj-$(CONFIG_HID_EZKEY) += hid-ezkey.o
+obj-$(CONFIG_HID_FT260) += hid-ft260.o
obj-$(CONFIG_HID_GEMBIRD) += hid-gembird.o
obj-$(CONFIG_HID_GFRM) += hid-gfrm.o
obj-$(CONFIG_HID_GLORIOUS) += hid-glorious.o
diff --git a/drivers/hid/hid-ft260.c b/drivers/hid/hid-ft260.c
new file mode 100644
index 000000000000..047aa85a7c83
--- /dev/null
+++ b/drivers/hid/hid-ft260.c
@@ -0,0 +1,1053 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * hid-ft260.c - FTDI FT260 USB HID to I2C host bridge
+ *
+ * Copyright (c) 2021, Michael Zaidman <michaelz@xxxxxxxxxxxxxx>
+ *
+ * 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_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[60]; /* 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];
+ 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);
+ 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_CTRL_BUSY)
+ return -EAGAIN;
+
+ if (report.bus_status & FT260_I2C_STATUS_BUS_BUSY)
+ return -EBUSY;
+
+ if (report.bus_status & FT260_I2C_STATUS_ERROR)
+ return -EIO;
+
+ ret = -EIO;
+
+ if (report.bus_status & FT260_I2C_STATUS_ADDR_NO_ACK)
+ ft260_dbg("unacknowledged address\n");
+
+ if (report.bus_status & FT260_I2C_STATUS_DATA_NO_ACK)
+ ft260_dbg("unacknowledged data\n");
+
+ if (report.bus_status & FT260_I2C_STATUS_ARBITR_LOST)
+ ft260_dbg("arbitration loss\n");
+
+ if (report.bus_status & FT260_I2C_STATUS_CTRL_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, "%s: failed to start transfer, ret %d\n",
+ __func__, 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,
+ int 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;
+
+ memcpy(rep->data, &data[idx], len);
+
+ ft260_dbg("rep %#02x addr %#02x off %d len %d d[0] %#02x\n",
+ rep->report, addr, idx, len, data[0]);
+
+ 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->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)
+{
+ struct ft260_i2c_read_request_report rep;
+ struct hid_device *hdev = dev->hdev;
+ int timeout;
+ int ret;
+
+ if (len > FT260_RD_DATA_MAX) {
+ hid_err(hdev, "%s: unsupported rd len: %d\n", __func__, len);
+ return -EINVAL;
+ }
+
+ dev->read_idx = 0;
+ dev->read_buf = data;
+ dev->read_len = len;
+
+ rep.report = FT260_I2C_READ_REQ;
+ rep.length = cpu_to_le16(len);
+ rep.address = addr;
+ rep.flag = flag;
+
+ ft260_dbg("rep %#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 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 wr 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)
+ 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_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_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_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);
+
+ 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;
+
+ 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);
+
+ 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: %#02x\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 FT260 USB HID to I2C host bridge");
+MODULE_AUTHOR("Michael Zaidman <michael.zaidman@xxxxxxxxx>");
+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