Loading Documentation/i2c/busses/i2c-diolan-u2c 0 → 100644 +26 −0 Original line number Diff line number Diff line Kernel driver i2c-diolan-u2c Supported adapters: * Diolan U2C-12 I2C-USB adapter Documentation: http://www.diolan.com/i2c/u2c12.html Author: Guenter Roeck <guenter.roeck@ericsson.com> Description ----------- This is the driver for the Diolan U2C-12 USB-I2C adapter. The Diolan U2C-12 I2C-USB Adapter provides a low cost solution to connect a computer to I2C slave devices using a USB interface. It also supports connectivity to SPI devices. This driver only supports the I2C interface of U2C-12. The driver does not use interrupts. Module parameters ----------------- * frequency: I2C bus frequency MAINTAINERS +6 −0 Original line number Diff line number Diff line Loading @@ -2130,6 +2130,12 @@ F: Documentation/serial/digiepca.txt F: drivers/char/epca* F: drivers/char/digi* DIOLAN U2C-12 I2C DRIVER M: Guenter Roeck <guenter.roeck@ericsson.com> L: linux-i2c@vger.kernel.org S: Maintained F: drivers/i2c/busses/i2c-diolan-u2c.c DIRECTORY NOTIFICATION (DNOTIFY) M: Eric Paris <eparis@parisplace.org> S: Maintained Loading drivers/i2c/busses/Kconfig +10 −0 Original line number Diff line number Diff line Loading @@ -676,6 +676,16 @@ config I2C_EG20T comment "External I2C/SMBus adapter drivers" config I2C_DIOLAN_U2C tristate "Diolan U2C-12 USB adapter" depends on USB help If you say yes to this option, support will be included for Diolan U2C-12, a USB to I2C interface. This driver can also be built as a module. If so, the module will be called i2c-diolan-u2c. config I2C_PARPORT tristate "Parallel port adapter" depends on PARPORT Loading drivers/i2c/busses/Makefile +1 −0 Original line number Diff line number Diff line Loading @@ -67,6 +67,7 @@ obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o obj-$(CONFIG_I2C_EG20T) += i2c-eg20t.o # External I2C/SMBus adapter drivers obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o obj-$(CONFIG_I2C_TAOS_EVM) += i2c-taos-evm.o Loading drivers/i2c/busses/i2c-diolan-u2c.c 0 → 100644 +535 −0 Original line number Diff line number Diff line /* * Driver for the Diolan u2c-12 USB-I2C adapter * * Copyright (c) 2010-2011 Ericsson AB * * Derived from: * i2c-tiny-usb.c * Copyright (C) 2006-2007 Till Harbaum (Till@Harbaum.org) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2. */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/module.h> #include <linux/types.h> #include <linux/slab.h> #include <linux/usb.h> #include <linux/i2c.h> #define DRIVER_NAME "i2c-diolan-u2c" #define USB_VENDOR_ID_DIOLAN 0x0abf #define USB_DEVICE_ID_DIOLAN_U2C 0x3370 #define DIOLAN_OUT_EP 0x02 #define DIOLAN_IN_EP 0x84 /* commands via USB, must match command ids in the firmware */ #define CMD_I2C_READ 0x01 #define CMD_I2C_WRITE 0x02 #define CMD_I2C_SCAN 0x03 /* Returns list of detected devices */ #define CMD_I2C_RELEASE_SDA 0x04 #define CMD_I2C_RELEASE_SCL 0x05 #define CMD_I2C_DROP_SDA 0x06 #define CMD_I2C_DROP_SCL 0x07 #define CMD_I2C_READ_SDA 0x08 #define CMD_I2C_READ_SCL 0x09 #define CMD_GET_FW_VERSION 0x0a #define CMD_GET_SERIAL 0x0b #define CMD_I2C_START 0x0c #define CMD_I2C_STOP 0x0d #define CMD_I2C_REPEATED_START 0x0e #define CMD_I2C_PUT_BYTE 0x0f #define CMD_I2C_GET_BYTE 0x10 #define CMD_I2C_PUT_ACK 0x11 #define CMD_I2C_GET_ACK 0x12 #define CMD_I2C_PUT_BYTE_ACK 0x13 #define CMD_I2C_GET_BYTE_ACK 0x14 #define CMD_I2C_SET_SPEED 0x1b #define CMD_I2C_GET_SPEED 0x1c #define CMD_I2C_SET_CLK_SYNC 0x24 #define CMD_I2C_GET_CLK_SYNC 0x25 #define CMD_I2C_SET_CLK_SYNC_TO 0x26 #define CMD_I2C_GET_CLK_SYNC_TO 0x27 #define RESP_OK 0x00 #define RESP_FAILED 0x01 #define RESP_BAD_MEMADDR 0x04 #define RESP_DATA_ERR 0x05 #define RESP_NOT_IMPLEMENTED 0x06 #define RESP_NACK 0x07 #define RESP_TIMEOUT 0x09 #define U2C_I2C_SPEED_FAST 0 /* 400 kHz */ #define U2C_I2C_SPEED_STD 1 /* 100 kHz */ #define U2C_I2C_SPEED_2KHZ 242 /* 2 kHz, minimum speed */ #define U2C_I2C_SPEED(f) ((DIV_ROUND_UP(1000000, (f)) - 10) / 2 + 1) #define U2C_I2C_FREQ_FAST 400000 #define U2C_I2C_FREQ_STD 100000 #define U2C_I2C_FREQ(s) (1000000 / (2 * (s - 1) + 10)) #define DIOLAN_USB_TIMEOUT 100 /* in ms */ #define DIOLAN_SYNC_TIMEOUT 20 /* in ms */ #define DIOLAN_OUTBUF_LEN 128 #define DIOLAN_FLUSH_LEN (DIOLAN_OUTBUF_LEN - 4) #define DIOLAN_INBUF_LEN 256 /* Maximum supported receive length */ /* Structure to hold all of our device specific stuff */ struct i2c_diolan_u2c { u8 obuffer[DIOLAN_OUTBUF_LEN]; /* output buffer */ u8 ibuffer[DIOLAN_INBUF_LEN]; /* input buffer */ struct usb_device *usb_dev; /* the usb device for this device */ struct usb_interface *interface;/* the interface for this device */ struct i2c_adapter adapter; /* i2c related things */ int olen; /* Output buffer length */ int ocount; /* Number of enqueued messages */ }; static uint frequency = U2C_I2C_FREQ_STD; /* I2C clock frequency in Hz */ module_param(frequency, uint, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(frequency, "I2C clock frequency in hertz"); /* usb layer */ /* Send command to device, and get response. */ static int diolan_usb_transfer(struct i2c_diolan_u2c *dev) { int ret = 0; int actual; int i; if (!dev->olen || !dev->ocount) return -EINVAL; ret = usb_bulk_msg(dev->usb_dev, usb_sndbulkpipe(dev->usb_dev, DIOLAN_OUT_EP), dev->obuffer, dev->olen, &actual, DIOLAN_USB_TIMEOUT); if (!ret) { for (i = 0; i < dev->ocount; i++) { int tmpret; tmpret = usb_bulk_msg(dev->usb_dev, usb_rcvbulkpipe(dev->usb_dev, DIOLAN_IN_EP), dev->ibuffer, sizeof(dev->ibuffer), &actual, DIOLAN_USB_TIMEOUT); /* * Stop command processing if a previous command * returned an error. * Note that we still need to retrieve all messages. */ if (ret < 0) continue; ret = tmpret; if (ret == 0 && actual > 0) { switch (dev->ibuffer[actual - 1]) { case RESP_NACK: /* * Return ENXIO if NACK was received as * response to the address phase, * EIO otherwise */ ret = i == 1 ? -ENXIO : -EIO; break; case RESP_TIMEOUT: ret = -ETIMEDOUT; break; case RESP_OK: /* strip off return code */ ret = actual - 1; break; default: ret = -EIO; break; } } } } dev->olen = 0; dev->ocount = 0; return ret; } static int diolan_write_cmd(struct i2c_diolan_u2c *dev, bool flush) { if (flush || dev->olen >= DIOLAN_FLUSH_LEN) return diolan_usb_transfer(dev); return 0; } /* Send command (no data) */ static int diolan_usb_cmd(struct i2c_diolan_u2c *dev, u8 command, bool flush) { dev->obuffer[dev->olen++] = command; dev->ocount++; return diolan_write_cmd(dev, flush); } /* Send command with one byte of data */ static int diolan_usb_cmd_data(struct i2c_diolan_u2c *dev, u8 command, u8 data, bool flush) { dev->obuffer[dev->olen++] = command; dev->obuffer[dev->olen++] = data; dev->ocount++; return diolan_write_cmd(dev, flush); } /* Send command with two bytes of data */ static int diolan_usb_cmd_data2(struct i2c_diolan_u2c *dev, u8 command, u8 d1, u8 d2, bool flush) { dev->obuffer[dev->olen++] = command; dev->obuffer[dev->olen++] = d1; dev->obuffer[dev->olen++] = d2; dev->ocount++; return diolan_write_cmd(dev, flush); } /* * Flush input queue. * If we don't do this at startup and the controller has queued up * messages which were not retrieved, it will stop responding * at some point. */ static void diolan_flush_input(struct i2c_diolan_u2c *dev) { int i; for (i = 0; i < 10; i++) { int actual = 0; int ret; ret = usb_bulk_msg(dev->usb_dev, usb_rcvbulkpipe(dev->usb_dev, DIOLAN_IN_EP), dev->ibuffer, sizeof(dev->ibuffer), &actual, DIOLAN_USB_TIMEOUT); if (ret < 0 || actual == 0) break; } if (i == 10) dev_err(&dev->interface->dev, "Failed to flush input buffer\n"); } static int diolan_i2c_start(struct i2c_diolan_u2c *dev) { return diolan_usb_cmd(dev, CMD_I2C_START, false); } static int diolan_i2c_repeated_start(struct i2c_diolan_u2c *dev) { return diolan_usb_cmd(dev, CMD_I2C_REPEATED_START, false); } static int diolan_i2c_stop(struct i2c_diolan_u2c *dev) { return diolan_usb_cmd(dev, CMD_I2C_STOP, true); } static int diolan_i2c_get_byte_ack(struct i2c_diolan_u2c *dev, bool ack, u8 *byte) { int ret; ret = diolan_usb_cmd_data(dev, CMD_I2C_GET_BYTE_ACK, ack, true); if (ret > 0) *byte = dev->ibuffer[0]; else if (ret == 0) ret = -EIO; return ret; } static int diolan_i2c_put_byte_ack(struct i2c_diolan_u2c *dev, u8 byte) { return diolan_usb_cmd_data(dev, CMD_I2C_PUT_BYTE_ACK, byte, false); } static int diolan_set_speed(struct i2c_diolan_u2c *dev, u8 speed) { return diolan_usb_cmd_data(dev, CMD_I2C_SET_SPEED, speed, true); } /* Enable or disable clock synchronization (stretching) */ static int diolan_set_clock_synch(struct i2c_diolan_u2c *dev, bool enable) { return diolan_usb_cmd_data(dev, CMD_I2C_SET_CLK_SYNC, enable, true); } /* Set clock synchronization timeout in ms */ static int diolan_set_clock_synch_timeout(struct i2c_diolan_u2c *dev, int ms) { int to_val = ms * 10; return diolan_usb_cmd_data2(dev, CMD_I2C_SET_CLK_SYNC_TO, to_val & 0xff, (to_val >> 8) & 0xff, true); } static void diolan_fw_version(struct i2c_diolan_u2c *dev) { int ret; ret = diolan_usb_cmd(dev, CMD_GET_FW_VERSION, true); if (ret >= 2) dev_info(&dev->interface->dev, "Diolan U2C firmware version %u.%u\n", (unsigned int)dev->ibuffer[0], (unsigned int)dev->ibuffer[1]); } static void diolan_get_serial(struct i2c_diolan_u2c *dev) { int ret; u32 serial; ret = diolan_usb_cmd(dev, CMD_GET_SERIAL, true); if (ret >= 4) { serial = le32_to_cpu(*(u32 *)dev->ibuffer); dev_info(&dev->interface->dev, "Diolan U2C serial number %u\n", serial); } } static int diolan_init(struct i2c_diolan_u2c *dev) { int speed, ret; if (frequency >= 200000) { speed = U2C_I2C_SPEED_FAST; frequency = U2C_I2C_FREQ_FAST; } else if (frequency >= 100000 || frequency == 0) { speed = U2C_I2C_SPEED_STD; frequency = U2C_I2C_FREQ_STD; } else { speed = U2C_I2C_SPEED(frequency); if (speed > U2C_I2C_SPEED_2KHZ) speed = U2C_I2C_SPEED_2KHZ; frequency = U2C_I2C_FREQ(speed); } dev_info(&dev->interface->dev, "Diolan U2C at USB bus %03d address %03d speed %d Hz\n", dev->usb_dev->bus->busnum, dev->usb_dev->devnum, frequency); diolan_flush_input(dev); diolan_fw_version(dev); diolan_get_serial(dev); /* Set I2C speed */ ret = diolan_set_speed(dev, speed); if (ret < 0) return ret; /* Configure I2C clock synchronization */ ret = diolan_set_clock_synch(dev, speed != U2C_I2C_SPEED_FAST); if (ret < 0) return ret; if (speed != U2C_I2C_SPEED_FAST) ret = diolan_set_clock_synch_timeout(dev, DIOLAN_SYNC_TIMEOUT); return ret; } /* i2c layer */ static int diolan_usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { struct i2c_diolan_u2c *dev = i2c_get_adapdata(adapter); struct i2c_msg *pmsg; int i, j; int ret, sret; ret = diolan_i2c_start(dev); if (ret < 0) return ret; for (i = 0; i < num; i++) { pmsg = &msgs[i]; if (i) { ret = diolan_i2c_repeated_start(dev); if (ret < 0) goto abort; } if (pmsg->flags & I2C_M_RD) { ret = diolan_i2c_put_byte_ack(dev, (pmsg->addr << 1) | 1); if (ret < 0) goto abort; for (j = 0; j < pmsg->len; j++) { u8 byte; bool ack = j < pmsg->len - 1; /* * Don't send NACK if this is the first byte * of a SMBUS_BLOCK message. */ if (j == 0 && (pmsg->flags & I2C_M_RECV_LEN)) ack = true; ret = diolan_i2c_get_byte_ack(dev, ack, &byte); if (ret < 0) goto abort; /* * Adjust count if first received byte is length */ if (j == 0 && (pmsg->flags & I2C_M_RECV_LEN)) { if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) { ret = -EPROTO; goto abort; } pmsg->len += byte; } pmsg->buf[j] = byte; } } else { ret = diolan_i2c_put_byte_ack(dev, pmsg->addr << 1); if (ret < 0) goto abort; for (j = 0; j < pmsg->len; j++) { ret = diolan_i2c_put_byte_ack(dev, pmsg->buf[j]); if (ret < 0) goto abort; } } } abort: sret = diolan_i2c_stop(dev); if (sret < 0 && ret >= 0) ret = sret; return ret; } /* * Return list of supported functionality. */ static u32 diolan_usb_func(struct i2c_adapter *a) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL; } static const struct i2c_algorithm diolan_usb_algorithm = { .master_xfer = diolan_usb_xfer, .functionality = diolan_usb_func, }; /* device layer */ static const struct usb_device_id diolan_u2c_table[] = { { USB_DEVICE(USB_VENDOR_ID_DIOLAN, USB_DEVICE_ID_DIOLAN_U2C) }, { } }; MODULE_DEVICE_TABLE(usb, diolan_u2c_table); static void diolan_u2c_free(struct i2c_diolan_u2c *dev) { usb_put_dev(dev->usb_dev); kfree(dev); } static int diolan_u2c_probe(struct usb_interface *interface, const struct usb_device_id *id) { struct i2c_diolan_u2c *dev; int ret; /* allocate memory for our device state and initialize it */ dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (dev == NULL) { dev_err(&interface->dev, "no memory for device state\n"); ret = -ENOMEM; goto error; } dev->usb_dev = usb_get_dev(interface_to_usbdev(interface)); dev->interface = interface; /* save our data pointer in this interface device */ usb_set_intfdata(interface, dev); /* setup i2c adapter description */ dev->adapter.owner = THIS_MODULE; dev->adapter.class = I2C_CLASS_HWMON; dev->adapter.algo = &diolan_usb_algorithm; i2c_set_adapdata(&dev->adapter, dev); snprintf(dev->adapter.name, sizeof(dev->adapter.name), DRIVER_NAME " at bus %03d device %03d", dev->usb_dev->bus->busnum, dev->usb_dev->devnum); dev->adapter.dev.parent = &dev->interface->dev; /* initialize diolan i2c interface */ ret = diolan_init(dev); if (ret < 0) { dev_err(&interface->dev, "failed to initialize adapter\n"); goto error_free; } /* and finally attach to i2c layer */ ret = i2c_add_adapter(&dev->adapter); if (ret < 0) { dev_err(&interface->dev, "failed to add I2C adapter\n"); goto error_free; } dev_dbg(&interface->dev, "connected " DRIVER_NAME "\n"); return 0; error_free: usb_set_intfdata(interface, NULL); diolan_u2c_free(dev); error: return ret; } static void diolan_u2c_disconnect(struct usb_interface *interface) { struct i2c_diolan_u2c *dev = usb_get_intfdata(interface); i2c_del_adapter(&dev->adapter); usb_set_intfdata(interface, NULL); diolan_u2c_free(dev); dev_dbg(&interface->dev, "disconnected\n"); } static struct usb_driver diolan_u2c_driver = { .name = DRIVER_NAME, .probe = diolan_u2c_probe, .disconnect = diolan_u2c_disconnect, .id_table = diolan_u2c_table, }; static int __init diolan_u2c_init(void) { /* register this driver with the USB subsystem */ return usb_register(&diolan_u2c_driver); } static void __exit diolan_u2c_exit(void) { /* deregister this driver with the USB subsystem */ usb_deregister(&diolan_u2c_driver); } module_init(diolan_u2c_init); module_exit(diolan_u2c_exit); MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>"); MODULE_DESCRIPTION(DRIVER_NAME " driver"); MODULE_LICENSE("GPL"); Loading
Documentation/i2c/busses/i2c-diolan-u2c 0 → 100644 +26 −0 Original line number Diff line number Diff line Kernel driver i2c-diolan-u2c Supported adapters: * Diolan U2C-12 I2C-USB adapter Documentation: http://www.diolan.com/i2c/u2c12.html Author: Guenter Roeck <guenter.roeck@ericsson.com> Description ----------- This is the driver for the Diolan U2C-12 USB-I2C adapter. The Diolan U2C-12 I2C-USB Adapter provides a low cost solution to connect a computer to I2C slave devices using a USB interface. It also supports connectivity to SPI devices. This driver only supports the I2C interface of U2C-12. The driver does not use interrupts. Module parameters ----------------- * frequency: I2C bus frequency
MAINTAINERS +6 −0 Original line number Diff line number Diff line Loading @@ -2130,6 +2130,12 @@ F: Documentation/serial/digiepca.txt F: drivers/char/epca* F: drivers/char/digi* DIOLAN U2C-12 I2C DRIVER M: Guenter Roeck <guenter.roeck@ericsson.com> L: linux-i2c@vger.kernel.org S: Maintained F: drivers/i2c/busses/i2c-diolan-u2c.c DIRECTORY NOTIFICATION (DNOTIFY) M: Eric Paris <eparis@parisplace.org> S: Maintained Loading
drivers/i2c/busses/Kconfig +10 −0 Original line number Diff line number Diff line Loading @@ -676,6 +676,16 @@ config I2C_EG20T comment "External I2C/SMBus adapter drivers" config I2C_DIOLAN_U2C tristate "Diolan U2C-12 USB adapter" depends on USB help If you say yes to this option, support will be included for Diolan U2C-12, a USB to I2C interface. This driver can also be built as a module. If so, the module will be called i2c-diolan-u2c. config I2C_PARPORT tristate "Parallel port adapter" depends on PARPORT Loading
drivers/i2c/busses/Makefile +1 −0 Original line number Diff line number Diff line Loading @@ -67,6 +67,7 @@ obj-$(CONFIG_I2C_XILINX) += i2c-xiic.o obj-$(CONFIG_I2C_EG20T) += i2c-eg20t.o # External I2C/SMBus adapter drivers obj-$(CONFIG_I2C_DIOLAN_U2C) += i2c-diolan-u2c.o obj-$(CONFIG_I2C_PARPORT) += i2c-parport.o obj-$(CONFIG_I2C_PARPORT_LIGHT) += i2c-parport-light.o obj-$(CONFIG_I2C_TAOS_EVM) += i2c-taos-evm.o Loading
drivers/i2c/busses/i2c-diolan-u2c.c 0 → 100644 +535 −0 Original line number Diff line number Diff line /* * Driver for the Diolan u2c-12 USB-I2C adapter * * Copyright (c) 2010-2011 Ericsson AB * * Derived from: * i2c-tiny-usb.c * Copyright (C) 2006-2007 Till Harbaum (Till@Harbaum.org) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2. */ #include <linux/kernel.h> #include <linux/errno.h> #include <linux/module.h> #include <linux/types.h> #include <linux/slab.h> #include <linux/usb.h> #include <linux/i2c.h> #define DRIVER_NAME "i2c-diolan-u2c" #define USB_VENDOR_ID_DIOLAN 0x0abf #define USB_DEVICE_ID_DIOLAN_U2C 0x3370 #define DIOLAN_OUT_EP 0x02 #define DIOLAN_IN_EP 0x84 /* commands via USB, must match command ids in the firmware */ #define CMD_I2C_READ 0x01 #define CMD_I2C_WRITE 0x02 #define CMD_I2C_SCAN 0x03 /* Returns list of detected devices */ #define CMD_I2C_RELEASE_SDA 0x04 #define CMD_I2C_RELEASE_SCL 0x05 #define CMD_I2C_DROP_SDA 0x06 #define CMD_I2C_DROP_SCL 0x07 #define CMD_I2C_READ_SDA 0x08 #define CMD_I2C_READ_SCL 0x09 #define CMD_GET_FW_VERSION 0x0a #define CMD_GET_SERIAL 0x0b #define CMD_I2C_START 0x0c #define CMD_I2C_STOP 0x0d #define CMD_I2C_REPEATED_START 0x0e #define CMD_I2C_PUT_BYTE 0x0f #define CMD_I2C_GET_BYTE 0x10 #define CMD_I2C_PUT_ACK 0x11 #define CMD_I2C_GET_ACK 0x12 #define CMD_I2C_PUT_BYTE_ACK 0x13 #define CMD_I2C_GET_BYTE_ACK 0x14 #define CMD_I2C_SET_SPEED 0x1b #define CMD_I2C_GET_SPEED 0x1c #define CMD_I2C_SET_CLK_SYNC 0x24 #define CMD_I2C_GET_CLK_SYNC 0x25 #define CMD_I2C_SET_CLK_SYNC_TO 0x26 #define CMD_I2C_GET_CLK_SYNC_TO 0x27 #define RESP_OK 0x00 #define RESP_FAILED 0x01 #define RESP_BAD_MEMADDR 0x04 #define RESP_DATA_ERR 0x05 #define RESP_NOT_IMPLEMENTED 0x06 #define RESP_NACK 0x07 #define RESP_TIMEOUT 0x09 #define U2C_I2C_SPEED_FAST 0 /* 400 kHz */ #define U2C_I2C_SPEED_STD 1 /* 100 kHz */ #define U2C_I2C_SPEED_2KHZ 242 /* 2 kHz, minimum speed */ #define U2C_I2C_SPEED(f) ((DIV_ROUND_UP(1000000, (f)) - 10) / 2 + 1) #define U2C_I2C_FREQ_FAST 400000 #define U2C_I2C_FREQ_STD 100000 #define U2C_I2C_FREQ(s) (1000000 / (2 * (s - 1) + 10)) #define DIOLAN_USB_TIMEOUT 100 /* in ms */ #define DIOLAN_SYNC_TIMEOUT 20 /* in ms */ #define DIOLAN_OUTBUF_LEN 128 #define DIOLAN_FLUSH_LEN (DIOLAN_OUTBUF_LEN - 4) #define DIOLAN_INBUF_LEN 256 /* Maximum supported receive length */ /* Structure to hold all of our device specific stuff */ struct i2c_diolan_u2c { u8 obuffer[DIOLAN_OUTBUF_LEN]; /* output buffer */ u8 ibuffer[DIOLAN_INBUF_LEN]; /* input buffer */ struct usb_device *usb_dev; /* the usb device for this device */ struct usb_interface *interface;/* the interface for this device */ struct i2c_adapter adapter; /* i2c related things */ int olen; /* Output buffer length */ int ocount; /* Number of enqueued messages */ }; static uint frequency = U2C_I2C_FREQ_STD; /* I2C clock frequency in Hz */ module_param(frequency, uint, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(frequency, "I2C clock frequency in hertz"); /* usb layer */ /* Send command to device, and get response. */ static int diolan_usb_transfer(struct i2c_diolan_u2c *dev) { int ret = 0; int actual; int i; if (!dev->olen || !dev->ocount) return -EINVAL; ret = usb_bulk_msg(dev->usb_dev, usb_sndbulkpipe(dev->usb_dev, DIOLAN_OUT_EP), dev->obuffer, dev->olen, &actual, DIOLAN_USB_TIMEOUT); if (!ret) { for (i = 0; i < dev->ocount; i++) { int tmpret; tmpret = usb_bulk_msg(dev->usb_dev, usb_rcvbulkpipe(dev->usb_dev, DIOLAN_IN_EP), dev->ibuffer, sizeof(dev->ibuffer), &actual, DIOLAN_USB_TIMEOUT); /* * Stop command processing if a previous command * returned an error. * Note that we still need to retrieve all messages. */ if (ret < 0) continue; ret = tmpret; if (ret == 0 && actual > 0) { switch (dev->ibuffer[actual - 1]) { case RESP_NACK: /* * Return ENXIO if NACK was received as * response to the address phase, * EIO otherwise */ ret = i == 1 ? -ENXIO : -EIO; break; case RESP_TIMEOUT: ret = -ETIMEDOUT; break; case RESP_OK: /* strip off return code */ ret = actual - 1; break; default: ret = -EIO; break; } } } } dev->olen = 0; dev->ocount = 0; return ret; } static int diolan_write_cmd(struct i2c_diolan_u2c *dev, bool flush) { if (flush || dev->olen >= DIOLAN_FLUSH_LEN) return diolan_usb_transfer(dev); return 0; } /* Send command (no data) */ static int diolan_usb_cmd(struct i2c_diolan_u2c *dev, u8 command, bool flush) { dev->obuffer[dev->olen++] = command; dev->ocount++; return diolan_write_cmd(dev, flush); } /* Send command with one byte of data */ static int diolan_usb_cmd_data(struct i2c_diolan_u2c *dev, u8 command, u8 data, bool flush) { dev->obuffer[dev->olen++] = command; dev->obuffer[dev->olen++] = data; dev->ocount++; return diolan_write_cmd(dev, flush); } /* Send command with two bytes of data */ static int diolan_usb_cmd_data2(struct i2c_diolan_u2c *dev, u8 command, u8 d1, u8 d2, bool flush) { dev->obuffer[dev->olen++] = command; dev->obuffer[dev->olen++] = d1; dev->obuffer[dev->olen++] = d2; dev->ocount++; return diolan_write_cmd(dev, flush); } /* * Flush input queue. * If we don't do this at startup and the controller has queued up * messages which were not retrieved, it will stop responding * at some point. */ static void diolan_flush_input(struct i2c_diolan_u2c *dev) { int i; for (i = 0; i < 10; i++) { int actual = 0; int ret; ret = usb_bulk_msg(dev->usb_dev, usb_rcvbulkpipe(dev->usb_dev, DIOLAN_IN_EP), dev->ibuffer, sizeof(dev->ibuffer), &actual, DIOLAN_USB_TIMEOUT); if (ret < 0 || actual == 0) break; } if (i == 10) dev_err(&dev->interface->dev, "Failed to flush input buffer\n"); } static int diolan_i2c_start(struct i2c_diolan_u2c *dev) { return diolan_usb_cmd(dev, CMD_I2C_START, false); } static int diolan_i2c_repeated_start(struct i2c_diolan_u2c *dev) { return diolan_usb_cmd(dev, CMD_I2C_REPEATED_START, false); } static int diolan_i2c_stop(struct i2c_diolan_u2c *dev) { return diolan_usb_cmd(dev, CMD_I2C_STOP, true); } static int diolan_i2c_get_byte_ack(struct i2c_diolan_u2c *dev, bool ack, u8 *byte) { int ret; ret = diolan_usb_cmd_data(dev, CMD_I2C_GET_BYTE_ACK, ack, true); if (ret > 0) *byte = dev->ibuffer[0]; else if (ret == 0) ret = -EIO; return ret; } static int diolan_i2c_put_byte_ack(struct i2c_diolan_u2c *dev, u8 byte) { return diolan_usb_cmd_data(dev, CMD_I2C_PUT_BYTE_ACK, byte, false); } static int diolan_set_speed(struct i2c_diolan_u2c *dev, u8 speed) { return diolan_usb_cmd_data(dev, CMD_I2C_SET_SPEED, speed, true); } /* Enable or disable clock synchronization (stretching) */ static int diolan_set_clock_synch(struct i2c_diolan_u2c *dev, bool enable) { return diolan_usb_cmd_data(dev, CMD_I2C_SET_CLK_SYNC, enable, true); } /* Set clock synchronization timeout in ms */ static int diolan_set_clock_synch_timeout(struct i2c_diolan_u2c *dev, int ms) { int to_val = ms * 10; return diolan_usb_cmd_data2(dev, CMD_I2C_SET_CLK_SYNC_TO, to_val & 0xff, (to_val >> 8) & 0xff, true); } static void diolan_fw_version(struct i2c_diolan_u2c *dev) { int ret; ret = diolan_usb_cmd(dev, CMD_GET_FW_VERSION, true); if (ret >= 2) dev_info(&dev->interface->dev, "Diolan U2C firmware version %u.%u\n", (unsigned int)dev->ibuffer[0], (unsigned int)dev->ibuffer[1]); } static void diolan_get_serial(struct i2c_diolan_u2c *dev) { int ret; u32 serial; ret = diolan_usb_cmd(dev, CMD_GET_SERIAL, true); if (ret >= 4) { serial = le32_to_cpu(*(u32 *)dev->ibuffer); dev_info(&dev->interface->dev, "Diolan U2C serial number %u\n", serial); } } static int diolan_init(struct i2c_diolan_u2c *dev) { int speed, ret; if (frequency >= 200000) { speed = U2C_I2C_SPEED_FAST; frequency = U2C_I2C_FREQ_FAST; } else if (frequency >= 100000 || frequency == 0) { speed = U2C_I2C_SPEED_STD; frequency = U2C_I2C_FREQ_STD; } else { speed = U2C_I2C_SPEED(frequency); if (speed > U2C_I2C_SPEED_2KHZ) speed = U2C_I2C_SPEED_2KHZ; frequency = U2C_I2C_FREQ(speed); } dev_info(&dev->interface->dev, "Diolan U2C at USB bus %03d address %03d speed %d Hz\n", dev->usb_dev->bus->busnum, dev->usb_dev->devnum, frequency); diolan_flush_input(dev); diolan_fw_version(dev); diolan_get_serial(dev); /* Set I2C speed */ ret = diolan_set_speed(dev, speed); if (ret < 0) return ret; /* Configure I2C clock synchronization */ ret = diolan_set_clock_synch(dev, speed != U2C_I2C_SPEED_FAST); if (ret < 0) return ret; if (speed != U2C_I2C_SPEED_FAST) ret = diolan_set_clock_synch_timeout(dev, DIOLAN_SYNC_TIMEOUT); return ret; } /* i2c layer */ static int diolan_usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num) { struct i2c_diolan_u2c *dev = i2c_get_adapdata(adapter); struct i2c_msg *pmsg; int i, j; int ret, sret; ret = diolan_i2c_start(dev); if (ret < 0) return ret; for (i = 0; i < num; i++) { pmsg = &msgs[i]; if (i) { ret = diolan_i2c_repeated_start(dev); if (ret < 0) goto abort; } if (pmsg->flags & I2C_M_RD) { ret = diolan_i2c_put_byte_ack(dev, (pmsg->addr << 1) | 1); if (ret < 0) goto abort; for (j = 0; j < pmsg->len; j++) { u8 byte; bool ack = j < pmsg->len - 1; /* * Don't send NACK if this is the first byte * of a SMBUS_BLOCK message. */ if (j == 0 && (pmsg->flags & I2C_M_RECV_LEN)) ack = true; ret = diolan_i2c_get_byte_ack(dev, ack, &byte); if (ret < 0) goto abort; /* * Adjust count if first received byte is length */ if (j == 0 && (pmsg->flags & I2C_M_RECV_LEN)) { if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) { ret = -EPROTO; goto abort; } pmsg->len += byte; } pmsg->buf[j] = byte; } } else { ret = diolan_i2c_put_byte_ack(dev, pmsg->addr << 1); if (ret < 0) goto abort; for (j = 0; j < pmsg->len; j++) { ret = diolan_i2c_put_byte_ack(dev, pmsg->buf[j]); if (ret < 0) goto abort; } } } abort: sret = diolan_i2c_stop(dev); if (sret < 0 && ret >= 0) ret = sret; return ret; } /* * Return list of supported functionality. */ static u32 diolan_usb_func(struct i2c_adapter *a) { return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL; } static const struct i2c_algorithm diolan_usb_algorithm = { .master_xfer = diolan_usb_xfer, .functionality = diolan_usb_func, }; /* device layer */ static const struct usb_device_id diolan_u2c_table[] = { { USB_DEVICE(USB_VENDOR_ID_DIOLAN, USB_DEVICE_ID_DIOLAN_U2C) }, { } }; MODULE_DEVICE_TABLE(usb, diolan_u2c_table); static void diolan_u2c_free(struct i2c_diolan_u2c *dev) { usb_put_dev(dev->usb_dev); kfree(dev); } static int diolan_u2c_probe(struct usb_interface *interface, const struct usb_device_id *id) { struct i2c_diolan_u2c *dev; int ret; /* allocate memory for our device state and initialize it */ dev = kzalloc(sizeof(*dev), GFP_KERNEL); if (dev == NULL) { dev_err(&interface->dev, "no memory for device state\n"); ret = -ENOMEM; goto error; } dev->usb_dev = usb_get_dev(interface_to_usbdev(interface)); dev->interface = interface; /* save our data pointer in this interface device */ usb_set_intfdata(interface, dev); /* setup i2c adapter description */ dev->adapter.owner = THIS_MODULE; dev->adapter.class = I2C_CLASS_HWMON; dev->adapter.algo = &diolan_usb_algorithm; i2c_set_adapdata(&dev->adapter, dev); snprintf(dev->adapter.name, sizeof(dev->adapter.name), DRIVER_NAME " at bus %03d device %03d", dev->usb_dev->bus->busnum, dev->usb_dev->devnum); dev->adapter.dev.parent = &dev->interface->dev; /* initialize diolan i2c interface */ ret = diolan_init(dev); if (ret < 0) { dev_err(&interface->dev, "failed to initialize adapter\n"); goto error_free; } /* and finally attach to i2c layer */ ret = i2c_add_adapter(&dev->adapter); if (ret < 0) { dev_err(&interface->dev, "failed to add I2C adapter\n"); goto error_free; } dev_dbg(&interface->dev, "connected " DRIVER_NAME "\n"); return 0; error_free: usb_set_intfdata(interface, NULL); diolan_u2c_free(dev); error: return ret; } static void diolan_u2c_disconnect(struct usb_interface *interface) { struct i2c_diolan_u2c *dev = usb_get_intfdata(interface); i2c_del_adapter(&dev->adapter); usb_set_intfdata(interface, NULL); diolan_u2c_free(dev); dev_dbg(&interface->dev, "disconnected\n"); } static struct usb_driver diolan_u2c_driver = { .name = DRIVER_NAME, .probe = diolan_u2c_probe, .disconnect = diolan_u2c_disconnect, .id_table = diolan_u2c_table, }; static int __init diolan_u2c_init(void) { /* register this driver with the USB subsystem */ return usb_register(&diolan_u2c_driver); } static void __exit diolan_u2c_exit(void) { /* deregister this driver with the USB subsystem */ usb_deregister(&diolan_u2c_driver); } module_init(diolan_u2c_init); module_exit(diolan_u2c_exit); MODULE_AUTHOR("Guenter Roeck <guenter.roeck@ericsson.com>"); MODULE_DESCRIPTION(DRIVER_NAME " driver"); MODULE_LICENSE("GPL");
