drivers/w1/dscore.c - linux/kernel/git/gregkh/char-misc - Git at Google

 /*
  *	dscore.c
  *
  * Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
  *
  *
  * 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; either version 2 of the License, or
  * (at your option) any later version.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */

 #include <linux/module.h>
 #include <linux/kernel.h>
 #include <linux/mod_devicetable.h>
 #include <linux/usb.h>

 #include "dscore.h"

 static struct usb_device_id ds_id_table [] = {
 	{ USB_DEVICE(0x04fa, 0x2490) },
 	{ },
 };
 MODULE_DEVICE_TABLE(usb, ds_id_table);

 static int ds_probe(struct usb_interface *, const struct usb_device_id *);
 static void ds_disconnect(struct usb_interface *);

 int ds_touch_bit(struct ds_device *, u8, u8 *);
 int ds_read_byte(struct ds_device *, u8 *);
 int ds_read_bit(struct ds_device *, u8 *);
 int ds_write_byte(struct ds_device *, u8);
 int ds_write_bit(struct ds_device *, u8);
 static int ds_start_pulse(struct ds_device *, int);
 int ds_reset(struct ds_device *, struct ds_status *);
 struct ds_device * ds_get_device(void);
 void ds_put_device(struct ds_device *);

 static inline void ds_dump_status(unsigned char *, unsigned char *, int);
 static int ds_send_control(struct ds_device *, u16, u16);
 static int ds_send_control_mode(struct ds_device *, u16, u16);
 static int ds_send_control_cmd(struct ds_device *, u16, u16);


 static struct usb_driver ds_driver = {
 	.name =		"DS9490R",
 	.probe =	ds_probe,
 	.disconnect =	ds_disconnect,
 	.id_table =	ds_id_table,
 };

 static struct ds_device *ds_dev;

 struct ds_device * ds_get_device(void)
 {
 	if (ds_dev)
 		atomic_inc(&ds_dev->refcnt);
 	return ds_dev;
 }

 void ds_put_device(struct ds_device *dev)
 {
 	atomic_dec(&dev->refcnt);
 }

 static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
 {
 	int err;

 	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 			CONTROL_CMD, 0x40, value, index, NULL, 0, 1000);
 	if (err < 0) {
 		printk(KERN_ERR "Failed to send command control message %x.%x: err=%d.\n",
 				value, index, err);
 		return err;
 	}

 	return err;
 }

 static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
 {
 	int err;

 	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 			MODE_CMD, 0x40, value, index, NULL, 0, 1000);
 	if (err < 0) {
 		printk(KERN_ERR "Failed to send mode control message %x.%x: err=%d.\n",
 				value, index, err);
 		return err;
 	}

 	return err;
 }

 static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
 {
 	int err;

 	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
 			COMM_CMD, 0x40, value, index, NULL, 0, 1000);
 	if (err < 0) {
 		printk(KERN_ERR "Failed to send control message %x.%x: err=%d.\n",
 				value, index, err);
 		return err;
 	}

 	return err;
 }

 static inline void ds_dump_status(unsigned char *buf, unsigned char *str, int off)
 {
 	printk("%45s: %8x\n", str, buf[off]);
 }

 static int ds_recv_status_nodump(struct ds_device *dev, struct ds_status *st,
 				 unsigned char *buf, int size)
 {
 	int count, err;

 	memset(st, 0, sizeof(st));

 	count = 0;
 	err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_STATUS]), buf, size, &count, 100);
 	if (err < 0) {
 		printk(KERN_ERR "Failed to read 1-wire data from 0x%x: err=%d.\n", dev->ep[EP_STATUS], err);
 		return err;
 	}

 	if (count >= sizeof(*st))
 		memcpy(st, buf, sizeof(*st));

 	return count;
 }

 static int ds_recv_status(struct ds_device *dev, struct ds_status *st)
 {
 	unsigned char buf[64];
 	int count, err = 0, i;

 	memcpy(st, buf, sizeof(*st));

 	count = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
 	if (count < 0)
 		return err;

 	printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
 	for (i=0; i<count; ++i)
 		printk("%02x ", buf[i]);
 	printk("\n");

 	if (count >= 16) {
 		ds_dump_status(buf, "enable flag", 0);
 		ds_dump_status(buf, "1-wire speed", 1);
 		ds_dump_status(buf, "strong pullup duration", 2);
 		ds_dump_status(buf, "programming pulse duration", 3);
 		ds_dump_status(buf, "pulldown slew rate control", 4);
 		ds_dump_status(buf, "write-1 low time", 5);
 		ds_dump_status(buf, "data sample offset/write-0 recovery time", 6);
 		ds_dump_status(buf, "reserved (test register)", 7);
 		ds_dump_status(buf, "device status flags", 8);
 		ds_dump_status(buf, "communication command byte 1", 9);
 		ds_dump_status(buf, "communication command byte 2", 10);
 		ds_dump_status(buf, "communication command buffer status", 11);
 		ds_dump_status(buf, "1-wire data output buffer status", 12);
 		ds_dump_status(buf, "1-wire data input buffer status", 13);
 		ds_dump_status(buf, "reserved", 14);
 		ds_dump_status(buf, "reserved", 15);
 	}

 	memcpy(st, buf, sizeof(*st));

 	if (st->status & ST_EPOF) {
 		printk(KERN_INFO "Resetting device after ST_EPOF.\n");
 		err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
 		if (err)
 			return err;
 		count = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
 		if (count < 0)
 			return err;
 	}
 #if 0
 	if (st->status & ST_IDLE) {
 		printk(KERN_INFO "Resetting pulse after ST_IDLE.\n");
 		err = ds_start_pulse(dev, PULLUP_PULSE_DURATION);
 		if (err)
 			return err;
 	}
 #endif

 	return err;
 }

 static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
 {
 	int count, err;
 	struct ds_status st;

 	count = 0;
 	err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
 				buf, size, &count, 1000);
 	if (err < 0) {
 		printk(KERN_INFO "Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
 		usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
 		ds_recv_status(dev, &st);
 		return err;
 	}

 #if 0
 	{
 		int i;

 		printk("%s: count=%d: ", __func__, count);
 		for (i=0; i<count; ++i)
 			printk("%02x ", buf[i]);
 		printk("\n");
 	}
 #endif
 	return count;
 }

 static int ds_send_data(struct ds_device *dev, unsigned char *buf, int len)
 {
 	int count, err;

 	count = 0;
 	err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
 	if (err < 0) {
 		printk(KERN_ERR "Failed to read 1-wire data from 0x02: err=%d.\n", err);
 		return err;
 	}

 	return err;
 }

 #if 0

 int ds_stop_pulse(struct ds_device *dev, int limit)
 {
 	struct ds_status st;
 	int count = 0, err = 0;
 	u8 buf[0x20];

 	do {
 		err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
 		if (err)
 			break;
 		err = ds_send_control(dev, CTL_RESUME_EXE, 0);
 		if (err)
 			break;
 		err = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
 		if (err)
 			break;

 		if ((st.status & ST_SPUA) == 0) {
 			err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
 			if (err)
 				break;
 		}
 	} while(++count < limit);

 	return err;
 }

 int ds_detect(struct ds_device *dev, struct ds_status *st)
 {
 	int err;

 	err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
 	if (err)
 		return err;

 	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, 0);
 	if (err)
 		return err;

 	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM | COMM_TYPE, 0x40);
 	if (err)
 		return err;

 	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
 	if (err)
 		return err;

 	err = ds_recv_status(dev, st);

 	return err;
 }

 #endif  /*  0  */

 static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
 {
 	u8 buf[0x20];
 	int err, count = 0;

 	do {
 		err = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
 #if 0
 		if (err >= 0) {
 			int i;
 			printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
 			for (i=0; i<err; ++i)
 				printk("%02x ", buf[i]);
 			printk("\n");
 		}
 #endif
 	} while(!(buf[0x08] & 0x20) && !(err < 0) && ++count < 100);


 	if (((err > 16) && (buf[0x10] & 0x01)) || count >= 100 || err < 0) {
 		ds_recv_status(dev, st);
 		return -1;
 	} else
 		return 0;
 }

 int ds_reset(struct ds_device *dev, struct ds_status *st)
 {
 	int err;

 	//err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_F | COMM_IM | COMM_SE, SPEED_FLEXIBLE);
 	err = ds_send_control(dev, 0x43, SPEED_NORMAL);
 	if (err)
 		return err;

 	ds_wait_status(dev, st);
 #if 0
 	if (st->command_buffer_status) {
 		printk(KERN_INFO "Short circuit.\n");
 		return -EIO;
 	}
 #endif

 	return 0;
 }

 #if 0
 int ds_set_speed(struct ds_device *dev, int speed)
 {
 	int err;

 	if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
 		return -EINVAL;

 	if (speed != SPEED_OVERDRIVE)
 		speed = SPEED_FLEXIBLE;

 	speed &= 0xff;

 	err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
 	if (err)
 		return err;

 	return err;
 }
 #endif  /*  0  */

 static int ds_start_pulse(struct ds_device *dev, int delay)
 {
 	int err;
 	u8 del = 1 + (u8)(delay >> 4);
 	struct ds_status st;

 #if 0
 	err = ds_stop_pulse(dev, 10);
 	if (err)
 		return err;

 	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE);
 	if (err)
 		return err;
 #endif
 	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
 	if (err)
 		return err;

 	err = ds_send_control(dev, COMM_PULSE | COMM_IM | COMM_F, 0);
 	if (err)
 		return err;

 	mdelay(delay);

 	ds_wait_status(dev, &st);

 	return err;
 }

 int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
 {
 	int err, count;
 	struct ds_status st;
 	u16 value = (COMM_BIT_IO | COMM_IM) | ((bit) ? COMM_D : 0);
 	u16 cmd;

 	err = ds_send_control(dev, value, 0);
 	if (err)
 		return err;

 	count = 0;
 	do {
 		err = ds_wait_status(dev, &st);
 		if (err)
 			return err;

 		cmd = st.command0 | (st.command1 << 8);
 	} while (cmd != value && ++count < 10);

 	if (err < 0 || count >= 10) {
 		printk(KERN_ERR "Failed to obtain status.\n");
 		return -EINVAL;
 	}

 	err = ds_recv_data(dev, tbit, sizeof(*tbit));
 	if (err < 0)
 		return err;

 	return 0;
 }

 int ds_write_bit(struct ds_device *dev, u8 bit)
 {
 	int err;
 	struct ds_status st;

 	err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | (bit) ? COMM_D : 0, 0);
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	return 0;
 }

 int ds_write_byte(struct ds_device *dev, u8 byte)
 {
 	int err;
 	struct ds_status st;
 	u8 rbyte;

 	err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | COMM_SPU, byte);
 	if (err)
 		return err;

 	err = ds_wait_status(dev, &st);
 	if (err)
 		return err;

 	err = ds_recv_data(dev, &rbyte, sizeof(rbyte));
 	if (err < 0)
 		return err;

 	ds_start_pulse(dev, PULLUP_PULSE_DURATION);

 	return !(byte == rbyte);
 }

 int ds_read_bit(struct ds_device *dev, u8 *bit)
 {
 	int err;

 	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE);
 	if (err)
 		return err;

 	err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_SPU | COMM_D, 0);
 	if (err)
 		return err;

 	err = ds_recv_data(dev, bit, sizeof(*bit));
 	if (err < 0)
 		return err;

 	return 0;
 }

 int ds_read_byte(struct ds_device *dev, u8 *byte)
 {
 	int err;
 	struct ds_status st;

 	err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM , 0xff);
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	err = ds_recv_data(dev, byte, sizeof(*byte));
 	if (err < 0)
 		return err;

 	return 0;
 }

 int ds_read_block(struct ds_device *dev, u8 *buf, int len)
 {
 	struct ds_status st;
 	int err;

 	if (len > 64*1024)
 		return -E2BIG;

 	memset(buf, 0xFF, len);

 	err = ds_send_data(dev, buf, len);
 	if (err < 0)
 		return err;

 	err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | COMM_SPU, len);
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	memset(buf, 0x00, len);
 	err = ds_recv_data(dev, buf, len);

 	return err;
 }

 int ds_write_block(struct ds_device *dev, u8 *buf, int len)
 {
 	int err;
 	struct ds_status st;

 	err = ds_send_data(dev, buf, len);
 	if (err < 0)
 		return err;

 	ds_wait_status(dev, &st);

 	err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | COMM_SPU, len);
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	err = ds_recv_data(dev, buf, len);
 	if (err < 0)
 		return err;

 	ds_start_pulse(dev, PULLUP_PULSE_DURATION);

 	return !(err == len);
 }

 #if 0

 int ds_search(struct ds_device *dev, u64 init, u64 *buf, u8 id_number, int conditional_search)
 {
 	int err;
 	u16 value, index;
 	struct ds_status st;

 	memset(buf, 0, sizeof(buf));

 	err = ds_send_data(ds_dev, (unsigned char *)&init, 8);
 	if (err)
 		return err;

 	ds_wait_status(ds_dev, &st);

 	value = COMM_SEARCH_ACCESS | COMM_IM | COMM_SM | COMM_F | COMM_RTS;
 	index = (conditional_search ? 0xEC : 0xF0) | (id_number << 8);
 	err = ds_send_control(ds_dev, value, index);
 	if (err)
 		return err;

 	ds_wait_status(ds_dev, &st);

 	err = ds_recv_data(ds_dev, (unsigned char *)buf, 8*id_number);
 	if (err < 0)
 		return err;

 	return err/8;
 }

 int ds_match_access(struct ds_device *dev, u64 init)
 {
 	int err;
 	struct ds_status st;

 	err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	err = ds_send_control(dev, COMM_MATCH_ACCESS | COMM_IM | COMM_RST, 0x0055);
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	return 0;
 }

 int ds_set_path(struct ds_device *dev, u64 init)
 {
 	int err;
 	struct ds_status st;
 	u8 buf[9];

 	memcpy(buf, &init, 8);
 	buf[8] = BRANCH_MAIN;

 	err = ds_send_data(dev, buf, sizeof(buf));
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	err = ds_send_control(dev, COMM_SET_PATH | COMM_IM | COMM_RST, 0);
 	if (err)
 		return err;

 	ds_wait_status(dev, &st);

 	return 0;
 }

 #endif  /*  0  */

 static int ds_probe(struct usb_interface *intf,
 		    const struct usb_device_id *udev_id)
 {
 	struct usb_device *udev = interface_to_usbdev(intf);
 	struct usb_endpoint_descriptor *endpoint;
 	struct usb_host_interface *iface_desc;
 	int i, err;

 	ds_dev = kmalloc(sizeof(struct ds_device), GFP_KERNEL);
 	if (!ds_dev) {
 		printk(KERN_INFO "Failed to allocate new DS9490R structure.\n");
 		return -ENOMEM;
 	}

 	ds_dev->udev = usb_get_dev(udev);
 	usb_set_intfdata(intf, ds_dev);

 	err = usb_set_interface(ds_dev->udev, intf->altsetting[0].desc.bInterfaceNumber, 3);
 	if (err) {
 		printk(KERN_ERR "Failed to set alternative setting 3 for %d interface: err=%d.\n",
 				intf->altsetting[0].desc.bInterfaceNumber, err);
 		return err;
 	}

 	err = usb_reset_configuration(ds_dev->udev);
 	if (err) {
 		printk(KERN_ERR "Failed to reset configuration: err=%d.\n", err);
 		return err;
 	}

 	iface_desc = &intf->altsetting[0];
 	if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
 		printk(KERN_INFO "Num endpoints=%d. It is not DS9490R.\n", iface_desc->desc.bNumEndpoints);
 		return -ENODEV;
 	}

 	atomic_set(&ds_dev->refcnt, 0);
 	memset(ds_dev->ep, 0, sizeof(ds_dev->ep));

 	/*
 	 * This loop doesn'd show control 0 endpoint,
 	 * so we will fill only 1-3 endpoints entry.
 	 */
 	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
 		endpoint = &iface_desc->endpoint[i].desc;

 		ds_dev->ep[i+1] = endpoint->bEndpointAddress;

 		printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
 			i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
 			(endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
 			endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
 	}

 #if 0
 	{
 		int err, i;
 		u64 buf[3];
 		u64 init=0xb30000002078ee81ull;
 		struct ds_status st;

 		ds_reset(ds_dev, &st);
 		err = ds_search(ds_dev, init, buf, 3, 0);
 		if (err < 0)
 			return err;
 		for (i=0; i<err; ++i)
 			printk("%d: %llx\n", i, buf[i]);

 		printk("Resetting...\n");
 		ds_reset(ds_dev, &st);
 		printk("Setting path for %llx.\n", init);
 		err = ds_set_path(ds_dev, init);
 		if (err)
 			return err;
 		printk("Calling MATCH_ACCESS.\n");
 		err = ds_match_access(ds_dev, init);
 		if (err)
 			return err;

 		printk("Searching the bus...\n");
 		err = ds_search(ds_dev, init, buf, 3, 0);

 		printk("ds_search() returned %d\n", err);

 		if (err < 0)
 			return err;
 		for (i=0; i<err; ++i)
 			printk("%d: %llx\n", i, buf[i]);

 		return 0;
 	}
 #endif

 	return 0;
 }

 static void ds_disconnect(struct usb_interface *intf)
 {
 	struct ds_device *dev;

 	dev = usb_get_intfdata(intf);
 	usb_set_intfdata(intf, NULL);

 	while (atomic_read(&dev->refcnt)) {
 		printk(KERN_INFO "Waiting for DS to become free: refcnt=%d.\n",
 				atomic_read(&dev->refcnt));

 		if (msleep_interruptible(1000))
 			flush_signals(current);
 	}

 	usb_put_dev(dev->udev);
 	kfree(dev);
 	ds_dev = NULL;
 }

 static int ds_init(void)
 {
 	int err;

 	err = usb_register(&ds_driver);
 	if (err) {
 		printk(KERN_INFO "Failed to register DS9490R USB device: err=%d.\n", err);
 		return err;
 	}

 	return 0;
 }

 static void ds_fini(void)
 {
 	usb_deregister(&ds_driver);
 }

 module_init(ds_init);
 module_exit(ds_fini);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");

 EXPORT_SYMBOL(ds_touch_bit);
 EXPORT_SYMBOL(ds_read_byte);
 EXPORT_SYMBOL(ds_read_bit);
 EXPORT_SYMBOL(ds_read_block);
 EXPORT_SYMBOL(ds_write_byte);
 EXPORT_SYMBOL(ds_write_bit);
 EXPORT_SYMBOL(ds_write_block);
 EXPORT_SYMBOL(ds_reset);
 EXPORT_SYMBOL(ds_get_device);
 EXPORT_SYMBOL(ds_put_device);

 /*
  * This functions can be used for EEPROM programming,
  * when driver will be included into mainline this will
  * require uncommenting.
  */
 #if 0
 EXPORT_SYMBOL(ds_start_pulse);
 EXPORT_SYMBOL(ds_set_speed);
 EXPORT_SYMBOL(ds_detect);
 EXPORT_SYMBOL(ds_stop_pulse);
 EXPORT_SYMBOL(ds_search);
 #endif
	/*
	* dscore.c
	*
	* Copyright (c) 2004 Evgeniy Polyakov <johnpol@2ka.mipt.ru>
	*
	*
	* 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; either version 2 of the License, or
	* (at your option) any later version.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	*/

	#include <linux/module.h>
	#include <linux/kernel.h>
	#include <linux/mod_devicetable.h>
	#include <linux/usb.h>

	#include "dscore.h"

	static struct usb_device_id ds_id_table [] = {
	{ USB_DEVICE(0x04fa, 0x2490) },
	{ },
	};
	MODULE_DEVICE_TABLE(usb, ds_id_table);

	static int ds_probe(struct usb_interface , const struct usb_device_id );
	static void ds_disconnect(struct usb_interface *);

	int ds_touch_bit(struct ds_device , u8, u8 );
	int ds_read_byte(struct ds_device , u8 );
	int ds_read_bit(struct ds_device , u8 );
	int ds_write_byte(struct ds_device *, u8);
	int ds_write_bit(struct ds_device *, u8);
	static int ds_start_pulse(struct ds_device *, int);
	int ds_reset(struct ds_device , struct ds_status );
	struct ds_device * ds_get_device(void);
	void ds_put_device(struct ds_device *);

	static inline void ds_dump_status(unsigned char , unsigned char , int);
	static int ds_send_control(struct ds_device *, u16, u16);
	static int ds_send_control_mode(struct ds_device *, u16, u16);
	static int ds_send_control_cmd(struct ds_device *, u16, u16);


	static struct usb_driver ds_driver = {
	.name = "DS9490R",
	.probe = ds_probe,
	.disconnect = ds_disconnect,
	.id_table = ds_id_table,
	};

	static struct ds_device *ds_dev;

	struct ds_device * ds_get_device(void)
	{
	if (ds_dev)
	atomic_inc(&ds_dev->refcnt);
	return ds_dev;
	}

	void ds_put_device(struct ds_device *dev)
	{
	atomic_dec(&dev->refcnt);
	}

	static int ds_send_control_cmd(struct ds_device *dev, u16 value, u16 index)
	{
	int err;

	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
	CONTROL_CMD, 0x40, value, index, NULL, 0, 1000);
	if (err < 0) {
	printk(KERN_ERR "Failed to send command control message %x.%x: err=%d.\n",
	value, index, err);
	return err;
	}

	return err;
	}

	static int ds_send_control_mode(struct ds_device *dev, u16 value, u16 index)
	{
	int err;

	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
	MODE_CMD, 0x40, value, index, NULL, 0, 1000);
	if (err < 0) {
	printk(KERN_ERR "Failed to send mode control message %x.%x: err=%d.\n",
	value, index, err);
	return err;
	}

	return err;
	}

	static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
	{
	int err;

	err = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, dev->ep[EP_CONTROL]),
	COMM_CMD, 0x40, value, index, NULL, 0, 1000);
	if (err < 0) {
	printk(KERN_ERR "Failed to send control message %x.%x: err=%d.\n",
	value, index, err);
	return err;
	}

	return err;
	}

	static inline void ds_dump_status(unsigned char buf, unsigned char str, int off)
	{
	printk("%45s: %8x\n", str, buf[off]);
	}

	static int ds_recv_status_nodump(struct ds_device dev, struct ds_status st,
	unsigned char *buf, int size)
	{
	int count, err;

	memset(st, 0, sizeof(st));

	count = 0;
	err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_STATUS]), buf, size, &count, 100);
	if (err < 0) {
	printk(KERN_ERR "Failed to read 1-wire data from 0x%x: err=%d.\n", dev->ep[EP_STATUS], err);
	return err;
	}

	if (count >= sizeof(*st))
	memcpy(st, buf, sizeof(*st));

	return count;
	}

	static int ds_recv_status(struct ds_device dev, struct ds_status st)
	{
	unsigned char buf[64];
	int count, err = 0, i;

	memcpy(st, buf, sizeof(*st));

	count = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
	if (count < 0)
	return err;

	printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
	for (i=0; i<count; ++i)
	printk("%02x ", buf[i]);
	printk("\n");

	if (count >= 16) {
	ds_dump_status(buf, "enable flag", 0);
	ds_dump_status(buf, "1-wire speed", 1);
	ds_dump_status(buf, "strong pullup duration", 2);
	ds_dump_status(buf, "programming pulse duration", 3);
	ds_dump_status(buf, "pulldown slew rate control", 4);
	ds_dump_status(buf, "write-1 low time", 5);
	ds_dump_status(buf, "data sample offset/write-0 recovery time", 6);
	ds_dump_status(buf, "reserved (test register)", 7);
	ds_dump_status(buf, "device status flags", 8);
	ds_dump_status(buf, "communication command byte 1", 9);
	ds_dump_status(buf, "communication command byte 2", 10);
	ds_dump_status(buf, "communication command buffer status", 11);
	ds_dump_status(buf, "1-wire data output buffer status", 12);
	ds_dump_status(buf, "1-wire data input buffer status", 13);
	ds_dump_status(buf, "reserved", 14);
	ds_dump_status(buf, "reserved", 15);
	}

	memcpy(st, buf, sizeof(*st));

	if (st->status & ST_EPOF) {
	printk(KERN_INFO "Resetting device after ST_EPOF.\n");
	err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
	if (err)
	return err;
	count = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
	if (count < 0)
	return err;
	}
	#if 0
	if (st->status & ST_IDLE) {
	printk(KERN_INFO "Resetting pulse after ST_IDLE.\n");
	err = ds_start_pulse(dev, PULLUP_PULSE_DURATION);
	if (err)
	return err;
	}
	#endif

	return err;
	}

	static int ds_recv_data(struct ds_device dev, unsigned char buf, int size)
	{
	int count, err;
	struct ds_status st;

	count = 0;
	err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
	buf, size, &count, 1000);
	if (err < 0) {
	printk(KERN_INFO "Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
	usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
	ds_recv_status(dev, &st);
	return err;
	}

	#if 0
	{
	int i;

	printk("%s: count=%d: ", __func__, count);
	for (i=0; i<count; ++i)
	printk("%02x ", buf[i]);
	printk("\n");
	}
	#endif
	return count;
	}

	static int ds_send_data(struct ds_device dev, unsigned char buf, int len)
	{
	int count, err;

	count = 0;
	err = usb_bulk_msg(dev->udev, usb_sndbulkpipe(dev->udev, dev->ep[EP_DATA_OUT]), buf, len, &count, 1000);
	if (err < 0) {
	printk(KERN_ERR "Failed to read 1-wire data from 0x02: err=%d.\n", err);
	return err;
	}

	return err;
	}

	#if 0

	int ds_stop_pulse(struct ds_device *dev, int limit)
	{
	struct ds_status st;
	int count = 0, err = 0;
	u8 buf[0x20];

	do {
	err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
	if (err)
	break;
	err = ds_send_control(dev, CTL_RESUME_EXE, 0);
	if (err)
	break;
	err = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
	if (err)
	break;

	if ((st.status & ST_SPUA) == 0) {
	err = ds_send_control_mode(dev, MOD_PULSE_EN, 0);
	if (err)
	break;
	}
	} while(++count < limit);

	return err;
	}

	int ds_detect(struct ds_device dev, struct ds_status st)
	{
	int err;

	err = ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
	if (err)
	return err;

	err = ds_send_control(dev, COMM_SET_DURATION \| COMM_IM, 0);
	if (err)
	return err;

	err = ds_send_control(dev, COMM_SET_DURATION \| COMM_IM \| COMM_TYPE, 0x40);
	if (err)
	return err;

	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_PROG);
	if (err)
	return err;

	err = ds_recv_status(dev, st);

	return err;
	}

	#endif /* 0 */

	static int ds_wait_status(struct ds_device dev, struct ds_status st)
	{
	u8 buf[0x20];
	int err, count = 0;

	do {
	err = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
	#if 0
	if (err >= 0) {
	int i;
	printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
	for (i=0; i<err; ++i)
	printk("%02x ", buf[i]);
	printk("\n");
	}
	#endif
	} while(!(buf[0x08] & 0x20) && !(err < 0) && ++count < 100);


	if (((err > 16) && (buf[0x10] & 0x01)) \|\| count >= 100 \|\| err < 0) {
	ds_recv_status(dev, st);
	return -1;
	} else
	return 0;
	}

	int ds_reset(struct ds_device dev, struct ds_status st)
	{
	int err;

	//err = ds_send_control(dev, COMM_1_WIRE_RESET \| COMM_F \| COMM_IM \| COMM_SE, SPEED_FLEXIBLE);
	err = ds_send_control(dev, 0x43, SPEED_NORMAL);
	if (err)
	return err;

	ds_wait_status(dev, st);
	#if 0
	if (st->command_buffer_status) {
	printk(KERN_INFO "Short circuit.\n");
	return -EIO;
	}
	#endif

	return 0;
	}

	#if 0
	int ds_set_speed(struct ds_device *dev, int speed)
	{
	int err;

	if (speed != SPEED_NORMAL && speed != SPEED_FLEXIBLE && speed != SPEED_OVERDRIVE)
	return -EINVAL;

	if (speed != SPEED_OVERDRIVE)
	speed = SPEED_FLEXIBLE;

	speed &= 0xff;

	err = ds_send_control_mode(dev, MOD_1WIRE_SPEED, speed);
	if (err)
	return err;

	return err;
	}
	#endif /* 0 */

	static int ds_start_pulse(struct ds_device *dev, int delay)
	{
	int err;
	u8 del = 1 + (u8)(delay >> 4);
	struct ds_status st;

	#if 0
	err = ds_stop_pulse(dev, 10);
	if (err)
	return err;

	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE);
	if (err)
	return err;
	#endif
	err = ds_send_control(dev, COMM_SET_DURATION \| COMM_IM, del);
	if (err)
	return err;

	err = ds_send_control(dev, COMM_PULSE \| COMM_IM \| COMM_F, 0);
	if (err)
	return err;

	mdelay(delay);

	ds_wait_status(dev, &st);

	return err;
	}

	int ds_touch_bit(struct ds_device dev, u8 bit, u8 tbit)
	{
	int err, count;
	struct ds_status st;
	u16 value = (COMM_BIT_IO \| COMM_IM) \| ((bit) ? COMM_D : 0);
	u16 cmd;

	err = ds_send_control(dev, value, 0);
	if (err)
	return err;

	count = 0;
	do {
	err = ds_wait_status(dev, &st);
	if (err)
	return err;

	cmd = st.command0 \| (st.command1 << 8);
	} while (cmd != value && ++count < 10);

	if (err < 0 \|\| count >= 10) {
	printk(KERN_ERR "Failed to obtain status.\n");
	return -EINVAL;
	}

	err = ds_recv_data(dev, tbit, sizeof(*tbit));
	if (err < 0)
	return err;

	return 0;
	}

	int ds_write_bit(struct ds_device *dev, u8 bit)
	{
	int err;
	struct ds_status st;

	err = ds_send_control(dev, COMM_BIT_IO \| COMM_IM \| (bit) ? COMM_D : 0, 0);
	if (err)
	return err;

	ds_wait_status(dev, &st);

	return 0;
	}

	int ds_write_byte(struct ds_device *dev, u8 byte)
	{
	int err;
	struct ds_status st;
	u8 rbyte;

	err = ds_send_control(dev, COMM_BYTE_IO \| COMM_IM \| COMM_SPU, byte);
	if (err)
	return err;

	err = ds_wait_status(dev, &st);
	if (err)
	return err;

	err = ds_recv_data(dev, &rbyte, sizeof(rbyte));
	if (err < 0)
	return err;

	ds_start_pulse(dev, PULLUP_PULSE_DURATION);

	return !(byte == rbyte);
	}

	int ds_read_bit(struct ds_device dev, u8 bit)
	{
	int err;

	err = ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE);
	if (err)
	return err;

	err = ds_send_control(dev, COMM_BIT_IO \| COMM_IM \| COMM_SPU \| COMM_D, 0);
	if (err)
	return err;

	err = ds_recv_data(dev, bit, sizeof(*bit));
	if (err < 0)
	return err;

	return 0;
	}

	int ds_read_byte(struct ds_device dev, u8 byte)
	{
	int err;
	struct ds_status st;

	err = ds_send_control(dev, COMM_BYTE_IO \| COMM_IM , 0xff);
	if (err)
	return err;

	ds_wait_status(dev, &st);

	err = ds_recv_data(dev, byte, sizeof(*byte));
	if (err < 0)
	return err;

	return 0;
	}

	int ds_read_block(struct ds_device dev, u8 buf, int len)
	{
	struct ds_status st;
	int err;

	if (len > 64*1024)
	return -E2BIG;

	memset(buf, 0xFF, len);

	err = ds_send_data(dev, buf, len);
	if (err < 0)
	return err;

	err = ds_send_control(dev, COMM_BLOCK_IO \| COMM_IM \| COMM_SPU, len);
	if (err)
	return err;

	ds_wait_status(dev, &st);

	memset(buf, 0x00, len);
	err = ds_recv_data(dev, buf, len);

	return err;
	}

	int ds_write_block(struct ds_device dev, u8 buf, int len)
	{
	int err;
	struct ds_status st;

	err = ds_send_data(dev, buf, len);
	if (err < 0)
	return err;

	ds_wait_status(dev, &st);

	err = ds_send_control(dev, COMM_BLOCK_IO \| COMM_IM \| COMM_SPU, len);
	if (err)
	return err;

	ds_wait_status(dev, &st);

	err = ds_recv_data(dev, buf, len);
	if (err < 0)
	return err;

	ds_start_pulse(dev, PULLUP_PULSE_DURATION);

	return !(err == len);
	}

	#if 0

	int ds_search(struct ds_device dev, u64 init, u64 buf, u8 id_number, int conditional_search)
	{
	int err;
	u16 value, index;
	struct ds_status st;

	memset(buf, 0, sizeof(buf));

	err = ds_send_data(ds_dev, (unsigned char *)&init, 8);
	if (err)
	return err;

	ds_wait_status(ds_dev, &st);

	value = COMM_SEARCH_ACCESS \| COMM_IM \| COMM_SM \| COMM_F \| COMM_RTS;
	index = (conditional_search ? 0xEC : 0xF0) \| (id_number << 8);
	err = ds_send_control(ds_dev, value, index);
	if (err)
	return err;

	ds_wait_status(ds_dev, &st);

	err = ds_recv_data(ds_dev, (unsigned char )buf, 8id_number);
	if (err < 0)
	return err;

	return err/8;
	}

	int ds_match_access(struct ds_device *dev, u64 init)
	{
	int err;
	struct ds_status st;

	err = ds_send_data(dev, (unsigned char *)&init, sizeof(init));
	if (err)
	return err;

	ds_wait_status(dev, &st);

	err = ds_send_control(dev, COMM_MATCH_ACCESS \| COMM_IM \| COMM_RST, 0x0055);
	if (err)
	return err;

	ds_wait_status(dev, &st);

	return 0;
	}

	int ds_set_path(struct ds_device *dev, u64 init)
	{
	int err;
	struct ds_status st;
	u8 buf[9];

	memcpy(buf, &init, 8);
	buf[8] = BRANCH_MAIN;

	err = ds_send_data(dev, buf, sizeof(buf));
	if (err)
	return err;

	ds_wait_status(dev, &st);

	err = ds_send_control(dev, COMM_SET_PATH \| COMM_IM \| COMM_RST, 0);
	if (err)
	return err;

	ds_wait_status(dev, &st);

	return 0;
	}

	#endif /* 0 */

	static int ds_probe(struct usb_interface *intf,
	const struct usb_device_id *udev_id)
	{
	struct usb_device *udev = interface_to_usbdev(intf);
	struct usb_endpoint_descriptor *endpoint;
	struct usb_host_interface *iface_desc;
	int i, err;

	ds_dev = kmalloc(sizeof(struct ds_device), GFP_KERNEL);
	if (!ds_dev) {
	printk(KERN_INFO "Failed to allocate new DS9490R structure.\n");
	return -ENOMEM;
	}

	ds_dev->udev = usb_get_dev(udev);
	usb_set_intfdata(intf, ds_dev);

	err = usb_set_interface(ds_dev->udev, intf->altsetting[0].desc.bInterfaceNumber, 3);
	if (err) {
	printk(KERN_ERR "Failed to set alternative setting 3 for %d interface: err=%d.\n",
	intf->altsetting[0].desc.bInterfaceNumber, err);
	return err;
	}

	err = usb_reset_configuration(ds_dev->udev);
	if (err) {
	printk(KERN_ERR "Failed to reset configuration: err=%d.\n", err);
	return err;
	}

	iface_desc = &intf->altsetting[0];
	if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
	printk(KERN_INFO "Num endpoints=%d. It is not DS9490R.\n", iface_desc->desc.bNumEndpoints);
	return -ENODEV;
	}

	atomic_set(&ds_dev->refcnt, 0);
	memset(ds_dev->ep, 0, sizeof(ds_dev->ep));

	/*
	* This loop doesn'd show control 0 endpoint,
	* so we will fill only 1-3 endpoints entry.
	*/
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
	endpoint = &iface_desc->endpoint[i].desc;

	ds_dev->ep[i+1] = endpoint->bEndpointAddress;

	printk("%d: addr=%x, size=%d, dir=%s, type=%x\n",
	i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
	(endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
	endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
	}

	#if 0
	{
	int err, i;
	u64 buf[3];
	u64 init=0xb30000002078ee81ull;
	struct ds_status st;

	ds_reset(ds_dev, &st);
	err = ds_search(ds_dev, init, buf, 3, 0);
	if (err < 0)
	return err;
	for (i=0; i<err; ++i)
	printk("%d: %llx\n", i, buf[i]);

	printk("Resetting...\n");
	ds_reset(ds_dev, &st);
	printk("Setting path for %llx.\n", init);
	err = ds_set_path(ds_dev, init);
	if (err)
	return err;
	printk("Calling MATCH_ACCESS.\n");
	err = ds_match_access(ds_dev, init);
	if (err)
	return err;

	printk("Searching the bus...\n");
	err = ds_search(ds_dev, init, buf, 3, 0);

	printk("ds_search() returned %d\n", err);

	if (err < 0)
	return err;
	for (i=0; i<err; ++i)
	printk("%d: %llx\n", i, buf[i]);

	return 0;
	}
	#endif

	return 0;
	}

	static void ds_disconnect(struct usb_interface *intf)
	{
	struct ds_device *dev;

	dev = usb_get_intfdata(intf);
	usb_set_intfdata(intf, NULL);

	while (atomic_read(&dev->refcnt)) {
	printk(KERN_INFO "Waiting for DS to become free: refcnt=%d.\n",
	atomic_read(&dev->refcnt));

	if (msleep_interruptible(1000))
	flush_signals(current);
	}

	usb_put_dev(dev->udev);
	kfree(dev);
	ds_dev = NULL;
	}

	static int ds_init(void)
	{
	int err;

	err = usb_register(&ds_driver);
	if (err) {
	printk(KERN_INFO "Failed to register DS9490R USB device: err=%d.\n", err);
	return err;
	}

	return 0;
	}

	static void ds_fini(void)
	{
	usb_deregister(&ds_driver);
	}

	module_init(ds_init);
	module_exit(ds_fini);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Evgeniy Polyakov <johnpol@2ka.mipt.ru>");

	EXPORT_SYMBOL(ds_touch_bit);
	EXPORT_SYMBOL(ds_read_byte);
	EXPORT_SYMBOL(ds_read_bit);
	EXPORT_SYMBOL(ds_read_block);
	EXPORT_SYMBOL(ds_write_byte);
	EXPORT_SYMBOL(ds_write_bit);
	EXPORT_SYMBOL(ds_write_block);
	EXPORT_SYMBOL(ds_reset);
	EXPORT_SYMBOL(ds_get_device);
	EXPORT_SYMBOL(ds_put_device);

	/*
	* This functions can be used for EEPROM programming,
	* when driver will be included into mainline this will
	* require uncommenting.
	*/
	#if 0
	EXPORT_SYMBOL(ds_start_pulse);
	EXPORT_SYMBOL(ds_set_speed);
	EXPORT_SYMBOL(ds_detect);
	EXPORT_SYMBOL(ds_stop_pulse);
	EXPORT_SYMBOL(ds_search);
	#endif