/*
   *	dscore.c
   *
   * Copyright (c) 2004 Evgeniy Polyakov <zbr@ioremap.net>
   *
   *
   * 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 <linux/slab.h>
  
  #include "../w1_int.h"
  #include "../w1.h"
  
  /* COMMAND TYPE CODES */
  #define CONTROL_CMD			0x00
  #define COMM_CMD			0x01
  #define MODE_CMD			0x02
  
  /* CONTROL COMMAND CODES */
  #define CTL_RESET_DEVICE		0x0000
  #define CTL_START_EXE			0x0001
  #define CTL_RESUME_EXE			0x0002
  #define CTL_HALT_EXE_IDLE		0x0003
  #define CTL_HALT_EXE_DONE		0x0004
  #define CTL_FLUSH_COMM_CMDS		0x0007
  #define CTL_FLUSH_RCV_BUFFER		0x0008
  #define CTL_FLUSH_XMT_BUFFER		0x0009
  #define CTL_GET_COMM_CMDS		0x000A
  
  /* MODE COMMAND CODES */
  #define MOD_PULSE_EN			0x0000
  #define MOD_SPEED_CHANGE_EN		0x0001
  #define MOD_1WIRE_SPEED			0x0002
  #define MOD_STRONG_PU_DURATION		0x0003
  #define MOD_PULLDOWN_SLEWRATE		0x0004
  #define MOD_PROG_PULSE_DURATION		0x0005
  #define MOD_WRITE1_LOWTIME		0x0006
  #define MOD_DSOW0_TREC			0x0007
  
  /* COMMUNICATION COMMAND CODES */
  #define COMM_ERROR_ESCAPE		0x0601
  #define COMM_SET_DURATION		0x0012
  #define COMM_BIT_IO			0x0020
  #define COMM_PULSE			0x0030
  #define COMM_1_WIRE_RESET		0x0042
  #define COMM_BYTE_IO			0x0052
  #define COMM_MATCH_ACCESS		0x0064
  #define COMM_BLOCK_IO			0x0074
  #define COMM_READ_STRAIGHT		0x0080
  #define COMM_DO_RELEASE			0x6092
  #define COMM_SET_PATH			0x00A2
  #define COMM_WRITE_SRAM_PAGE		0x00B2
  #define COMM_WRITE_EPROM		0x00C4
  #define COMM_READ_CRC_PROT_PAGE		0x00D4
  #define COMM_READ_REDIRECT_PAGE_CRC	0x21E4
  #define COMM_SEARCH_ACCESS		0x00F4
  
  /* Communication command bits */
  #define COMM_TYPE			0x0008
  #define COMM_SE				0x0008
  #define COMM_D				0x0008
  #define COMM_Z				0x0008
  #define COMM_CH				0x0008
  #define COMM_SM				0x0008
  #define COMM_R				0x0008
  #define COMM_IM				0x0001
  
  #define COMM_PS				0x4000
  #define COMM_PST			0x4000
  #define COMM_CIB			0x4000
  #define COMM_RTS			0x4000
  #define COMM_DT				0x2000
  #define COMM_SPU			0x1000
  #define COMM_F				0x0800
  #define COMM_NTF			0x0400
  #define COMM_ICP			0x0200
  #define COMM_RST			0x0100
  
  #define PULSE_PROG			0x01
  #define PULSE_SPUE			0x02
  
  #define BRANCH_MAIN			0xCC
  #define BRANCH_AUX			0x33
  
  /* Status flags */
  #define ST_SPUA				0x01  /* Strong Pull-up is active */
  #define ST_PRGA				0x02  /* 12V programming pulse is being generated */
  #define ST_12VP				0x04  /* external 12V programming voltage is present */
  #define ST_PMOD				0x08  /* DS2490 powered from USB and external sources */
  #define ST_HALT				0x10  /* DS2490 is currently halted */
  #define ST_IDLE				0x20  /* DS2490 is currently idle */
  #define ST_EPOF				0x80
  
  /* Result Register flags */
  #define RR_DETECT			0xA5 /* New device detected */
  #define RR_NRS				0x01 /* Reset no presence or ... */
  #define RR_SH				0x02 /* short on reset or set path */
  #define RR_APP				0x04 /* alarming presence on reset */
  #define RR_VPP				0x08 /* 12V expected not seen */
  #define RR_CMP				0x10 /* compare error */
  #define RR_CRC				0x20 /* CRC error detected */
  #define RR_RDP				0x40 /* redirected page */
  #define RR_EOS				0x80 /* end of search error */
  
  #define SPEED_NORMAL			0x00
  #define SPEED_FLEXIBLE			0x01
  #define SPEED_OVERDRIVE			0x02
  
  #define NUM_EP				4
  #define EP_CONTROL			0
  #define EP_STATUS			1
  #define EP_DATA_OUT			2
  #define EP_DATA_IN			3
  
  struct ds_device
  {
  	struct list_head	ds_entry;
  
  	struct usb_device	*udev;
  	struct usb_interface	*intf;
  
  	int			ep[NUM_EP];
  
  	/* Strong PullUp
  	 * 0: pullup not active, else duration in milliseconds
  	 */
  	int			spu_sleep;
  	/* spu_bit contains COMM_SPU or 0 depending on if the strong pullup
  	 * should be active or not for writes.
  	 */
  	u16			spu_bit;
  
  	struct w1_bus_master	master;
  };
  
  struct ds_status
  {
  	u8			enable;
  	u8			speed;
  	u8			pullup_dur;
  	u8			ppuls_dur;
  	u8			pulldown_slew;
  	u8			write1_time;
  	u8			write0_time;
  	u8			reserved0;
  	u8			status;
  	u8			command0;
  	u8			command1;
  	u8			command_buffer_status;
  	u8			data_out_buffer_status;
  	u8			data_in_buffer_status;
  	u8			reserved1;
  	u8			reserved2;
  
  };
  
  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 *);
  
  static int ds_send_control(struct ds_device *, u16, u16);
  static int ds_send_control_cmd(struct ds_device *, u16, u16);
  
  static LIST_HEAD(ds_devices);
  static DEFINE_MUTEX(ds_mutex);
  
  static struct usb_driver ds_driver = {
  	.name =		"DS9490R",
  	.probe =	ds_probe,
  	.disconnect =	ds_disconnect,
  	.id_table =	ds_id_table,
  };
  
  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.
  ",
  				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.
  ",
  				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.
  ",
  				value, index, err);
  		return err;
  	}
  
  	return err;
  }
  
  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.
  ", dev->ep[EP_STATUS], err);
  		return err;
  	}
  
  	if (count >= sizeof(*st))
  		memcpy(st, buf, sizeof(*st));
  
  	return count;
  }
  
  static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
  {
  	printk(KERN_INFO "%45s: %8x
  ", str, buf[off]);
  }
  
  static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
  {
  	int i;
  
  	printk(KERN_INFO "0x%x: count=%d, status: ", dev->ep[EP_STATUS], count);
  	for (i=0; i<count; ++i)
  		printk("%02x ", buf[i]);
  	printk(KERN_INFO "
  ");
  
  	if (count >= 16) {
  		ds_print_msg(buf, "enable flag", 0);
  		ds_print_msg(buf, "1-wire speed", 1);
  		ds_print_msg(buf, "strong pullup duration", 2);
  		ds_print_msg(buf, "programming pulse duration", 3);
  		ds_print_msg(buf, "pulldown slew rate control", 4);
  		ds_print_msg(buf, "write-1 low time", 5);
  		ds_print_msg(buf, "data sample offset/write-0 recovery time",
  			6);
  		ds_print_msg(buf, "reserved (test register)", 7);
  		ds_print_msg(buf, "device status flags", 8);
  		ds_print_msg(buf, "communication command byte 1", 9);
  		ds_print_msg(buf, "communication command byte 2", 10);
  		ds_print_msg(buf, "communication command buffer status", 11);
  		ds_print_msg(buf, "1-wire data output buffer status", 12);
  		ds_print_msg(buf, "1-wire data input buffer status", 13);
  		ds_print_msg(buf, "reserved", 14);
  		ds_print_msg(buf, "reserved", 15);
  	}
  	for (i = 16; i < count; ++i) {
  		if (buf[i] == RR_DETECT) {
  			ds_print_msg(buf, "new device detect", i);
  			continue;
  		}
  		ds_print_msg(buf, "Result Register Value: ", i);
  		if (buf[i] & RR_NRS)
  			printk(KERN_INFO "NRS: Reset no presence or ...
  ");
  		if (buf[i] & RR_SH)
  			printk(KERN_INFO "SH: short on reset or set path
  ");
  		if (buf[i] & RR_APP)
  			printk(KERN_INFO "APP: alarming presence on reset
  ");
  		if (buf[i] & RR_VPP)
  			printk(KERN_INFO "VPP: 12V expected not seen
  ");
  		if (buf[i] & RR_CMP)
  			printk(KERN_INFO "CMP: compare error
  ");
  		if (buf[i] & RR_CRC)
  			printk(KERN_INFO "CRC: CRC error detected
  ");
  		if (buf[i] & RR_RDP)
  			printk(KERN_INFO "RDP: redirected page
  ");
  		if (buf[i] & RR_EOS)
  			printk(KERN_INFO "EOS: end of search error
  ");
  	}
  }
  
  static void ds_reset_device(struct ds_device *dev)
  {
  	ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
  	/* Always allow strong pullup which allow individual writes to use
  	 * the strong pullup.
  	 */
  	if (ds_send_control_mode(dev, MOD_PULSE_EN, PULSE_SPUE))
  		printk(KERN_ERR "ds_reset_device: "
  			"Error allowing strong pullup
  ");
  	/* Chip strong pullup time was cleared. */
  	if (dev->spu_sleep) {
  		/* lower 4 bits are 0, see ds_set_pullup */
  		u8 del = dev->spu_sleep>>4;
  		if (ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del))
  			printk(KERN_ERR "ds_reset_device: "
  				"Error setting duration
  ");
  	}
  }
  
  static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
  {
  	int count, err;
  	struct ds_status st;
  
  	/* Careful on size.  If size is less than what is available in
  	 * the input buffer, the device fails the bulk transfer and
  	 * clears the input buffer.  It could read the maximum size of
  	 * the data buffer, but then do you return the first, last, or
  	 * some set of the middle size bytes?  As long as the rest of
  	 * the code is correct there will be size bytes waiting.  A
  	 * call to ds_wait_status will wait until the device is idle
  	 * and any data to be received would have been available.
  	 */
  	count = 0;
  	err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
  				buf, size, &count, 1000);
  	if (err < 0) {
  		u8 buf[0x20];
  		int count;
  
  		printk(KERN_INFO "Clearing ep0x%x.
  ", dev->ep[EP_DATA_IN]);
  		usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
  
  		count = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
  		ds_dump_status(dev, buf, count);
  		return err;
  	}
  
  #if 0
  	{
  		int i;
  
  		printk("%s: count=%d: ", __func__, count);
  		for (i=0; i<count; ++i)
  			printk("%02x ", buf[i]);
  		printk("
  ");
  	}
  #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 write 1-wire data to ep0x%x: "
  			"err=%d.
  ", dev->ep[EP_DATA_OUT], 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_dump_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("
  ");
  		}
  #endif
  	} while (!(buf[0x08] & ST_IDLE) && !(err < 0) && ++count < 100);
  
  	if (err >= 16 && st->status & ST_EPOF) {
  		printk(KERN_INFO "Resetting device after ST_EPOF.
  ");
  		ds_reset_device(dev);
  		/* Always dump the device status. */
  		count = 101;
  	}
  
  	/* Dump the status for errors or if there is extended return data.
  	 * The extended status includes new device detection (maybe someone
  	 * can do something with it).
  	 */
  	if (err > 16 || count >= 100 || err < 0)
  		ds_dump_status(dev, buf, err);
  
  	/* Extended data isn't an error.  Well, a short is, but the dump
  	 * would have already told the user that and we can't do anything
  	 * about it in software anyway.
  	 */
  	if (count >= 100 || err < 0)
  		return -1;
  	else
  		return 0;
  }
  
  static int ds_reset(struct ds_device *dev)
  {
  	int err;
  
  	/* Other potentionally interesting flags for reset.
  	 *
  	 * COMM_NTF: Return result register feedback.  This could be used to
  	 * detect some conditions such as short, alarming presence, or
  	 * detect if a new device was detected.
  	 *
  	 * COMM_SE which allows SPEED_NORMAL, SPEED_FLEXIBLE, SPEED_OVERDRIVE:
  	 * Select the data transfer rate.
  	 */
  	err = ds_send_control(dev, COMM_1_WIRE_RESET | COMM_IM, SPEED_NORMAL);
  	if (err)
  		return err;
  
  	return 0;
  }
  
  #if 0
  static 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_set_pullup(struct ds_device *dev, int delay)
  {
  	int err = 0;
  	u8 del = 1 + (u8)(delay >> 4);
  	/* Just storing delay would not get the trunication and roundup. */
  	int ms = del<<4;
  
  	/* Enable spu_bit if a delay is set. */
  	dev->spu_bit = delay ? COMM_SPU : 0;
  	/* If delay is zero, it has already been disabled, if the time is
  	 * the same as the hardware was last programmed to, there is also
  	 * nothing more to do.  Compare with the recalculated value ms
  	 * rather than del or delay which can have a different value.
  	 */
  	if (delay == 0 || ms == dev->spu_sleep)
  		return err;
  
  	err = ds_send_control(dev, COMM_SET_DURATION | COMM_IM, del);
  	if (err)
  		return err;
  
  	dev->spu_sleep = ms;
  
  	return err;
  }
  
  static int ds_touch_bit(struct ds_device *dev, u8 bit, u8 *tbit)
  {
  	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);
  
  	err = ds_recv_data(dev, tbit, sizeof(*tbit));
  	if (err < 0)
  		return err;
  
  	return 0;
  }
  
  #if 0
  static int ds_write_bit(struct ds_device *dev, u8 bit)
  {
  	int err;
  	struct ds_status st;
  
  	/* Set COMM_ICP to write without a readback.  Note, this will
  	 * produce one time slot, a down followed by an up with COMM_D
  	 * only determing the timing.
  	 */
  	err = ds_send_control(dev, COMM_BIT_IO | COMM_IM | COMM_ICP |
  		(bit ? COMM_D : 0), 0);
  	if (err)
  		return err;
  
  	ds_wait_status(dev, &st);
  
  	return 0;
  }
  #endif
  
  static 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 | dev->spu_bit, byte);
  	if (err)
  		return err;
  
  	if (dev->spu_bit)
  		msleep(dev->spu_sleep);
  
  	err = ds_wait_status(dev, &st);
  	if (err)
  		return err;
  
  	err = ds_recv_data(dev, &rbyte, sizeof(rbyte));
  	if (err < 0)
  		return err;
  
  	return !(byte == rbyte);
  }
  
  static 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;
  }
  
  static 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, len);
  	if (err)
  		return err;
  
  	ds_wait_status(dev, &st);
  
  	memset(buf, 0x00, len);
  	err = ds_recv_data(dev, buf, len);
  
  	return err;
  }
  
  static 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;
  
  	err = ds_send_control(dev, COMM_BLOCK_IO | COMM_IM | dev->spu_bit, len);
  	if (err)
  		return err;
  
  	if (dev->spu_bit)
  		msleep(dev->spu_sleep);
  
  	ds_wait_status(dev, &st);
  
  	err = ds_recv_data(dev, buf, len);
  	if (err < 0)
  		return err;
  
  	return !(err == len);
  }
  
  #if 0
  
  static 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;
  }
  
  static 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;
  }
  
  static 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 u8 ds9490r_touch_bit(void *data, u8 bit)
  {
  	u8 ret;
  	struct ds_device *dev = data;
  
  	if (ds_touch_bit(dev, bit, &ret))
  		return 0;
  
  	return ret;
  }
  
  #if 0
  static void ds9490r_write_bit(void *data, u8 bit)
  {
  	struct ds_device *dev = data;
  
  	ds_write_bit(dev, bit);
  }
  
  static u8 ds9490r_read_bit(void *data)
  {
  	struct ds_device *dev = data;
  	int err;
  	u8 bit = 0;
  
  	err = ds_touch_bit(dev, 1, &bit);
  	if (err)
  		return 0;
  
  	return bit & 1;
  }
  #endif
  
  static void ds9490r_write_byte(void *data, u8 byte)
  {
  	struct ds_device *dev = data;
  
  	ds_write_byte(dev, byte);
  }
  
  static u8 ds9490r_read_byte(void *data)
  {
  	struct ds_device *dev = data;
  	int err;
  	u8 byte = 0;
  
  	err = ds_read_byte(dev, &byte);
  	if (err)
  		return 0;
  
  	return byte;
  }
  
  static void ds9490r_write_block(void *data, const u8 *buf, int len)
  {
  	struct ds_device *dev = data;
  
  	ds_write_block(dev, (u8 *)buf, len);
  }
  
  static u8 ds9490r_read_block(void *data, u8 *buf, int len)
  {
  	struct ds_device *dev = data;
  	int err;
  
  	err = ds_read_block(dev, buf, len);
  	if (err < 0)
  		return 0;
  
  	return len;
  }
  
  static u8 ds9490r_reset(void *data)
  {
  	struct ds_device *dev = data;
  	int err;
  
  	err = ds_reset(dev);
  	if (err)
  		return 1;
  
  	return 0;
  }
  
  static u8 ds9490r_set_pullup(void *data, int delay)
  {
  	struct ds_device *dev = data;
  
  	if (ds_set_pullup(dev, delay))
  		return 1;
  
  	return 0;
  }
  
  static int ds_w1_init(struct ds_device *dev)
  {
  	memset(&dev->master, 0, sizeof(struct w1_bus_master));
  
  	/* Reset the device as it can be in a bad state.
  	 * This is necessary because a block write will wait for data
  	 * to be placed in the output buffer and block any later
  	 * commands which will keep accumulating and the device will
  	 * not be idle.  Another case is removing the ds2490 module
  	 * while a bus search is in progress, somehow a few commands
  	 * get through, but the input transfers fail leaving data in
  	 * the input buffer.  This will cause the next read to fail
  	 * see the note in ds_recv_data.
  	 */
  	ds_reset_device(dev);
  
  	dev->master.data	= dev;
  	dev->master.touch_bit	= &ds9490r_touch_bit;
  	/* read_bit and write_bit in w1_bus_master are expected to set and
  	 * sample the line level.  For write_bit that means it is expected to
  	 * set it to that value and leave it there.  ds2490 only supports an
  	 * individual time slot at the lowest level.  The requirement from
  	 * pulling the bus state down to reading the state is 15us, something
  	 * that isn't realistic on the USB bus anyway.
  	dev->master.read_bit	= &ds9490r_read_bit;
  	dev->master.write_bit	= &ds9490r_write_bit;
  	*/
  	dev->master.read_byte	= &ds9490r_read_byte;
  	dev->master.write_byte	= &ds9490r_write_byte;
  	dev->master.read_block	= &ds9490r_read_block;
  	dev->master.write_block	= &ds9490r_write_block;
  	dev->master.reset_bus	= &ds9490r_reset;
  	dev->master.set_pullup	= &ds9490r_set_pullup;
  
  	return w1_add_master_device(&dev->master);
  }
  
  static void ds_w1_fini(struct ds_device *dev)
  {
  	w1_remove_master_device(&dev->master);
  }
  
  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;
  	struct ds_device *dev;
  	int i, err;
  
  	dev = kmalloc(sizeof(struct ds_device), GFP_KERNEL);
  	if (!dev) {
  		printk(KERN_INFO "Failed to allocate new DS9490R structure.
  ");
  		return -ENOMEM;
  	}
  	dev->spu_sleep = 0;
  	dev->spu_bit = 0;
  	dev->udev = usb_get_dev(udev);
  	if (!dev->udev) {
  		err = -ENOMEM;
  		goto err_out_free;
  	}
  	memset(dev->ep, 0, sizeof(dev->ep));
  
  	usb_set_intfdata(intf, dev);
  
  	err = usb_set_interface(dev->udev, intf->altsetting[0].desc.bInterfaceNumber, 3);
  	if (err) {
  		printk(KERN_ERR "Failed to set alternative setting 3 for %d interface: err=%d.
  ",
  				intf->altsetting[0].desc.bInterfaceNumber, err);
  		goto err_out_clear;
  	}
  
  	err = usb_reset_configuration(dev->udev);
  	if (err) {
  		printk(KERN_ERR "Failed to reset configuration: err=%d.
  ", err);
  		goto err_out_clear;
  	}
  
  	iface_desc = &intf->altsetting[0];
  	if (iface_desc->desc.bNumEndpoints != NUM_EP-1) {
  		printk(KERN_INFO "Num endpoints=%d. It is not DS9490R.
  ", iface_desc->desc.bNumEndpoints);
  		err = -EINVAL;
  		goto err_out_clear;
  	}
  
  	/*
  	 * 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;
  
  		dev->ep[i+1] = endpoint->bEndpointAddress;
  #if 0
  		printk("%d: addr=%x, size=%d, dir=%s, type=%x
  ",
  			i, endpoint->bEndpointAddress, le16_to_cpu(endpoint->wMaxPacketSize),
  			(endpoint->bEndpointAddress & USB_DIR_IN)?"IN":"OUT",
  			endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK);
  #endif
  	}
  
  	err = ds_w1_init(dev);
  	if (err)
  		goto err_out_clear;
  
  	mutex_lock(&ds_mutex);
  	list_add_tail(&dev->ds_entry, &ds_devices);
  	mutex_unlock(&ds_mutex);
  
  	return 0;
  
  err_out_clear:
  	usb_set_intfdata(intf, NULL);
  	usb_put_dev(dev->udev);
  err_out_free:
  	kfree(dev);
  	return err;
  }
  
  static void ds_disconnect(struct usb_interface *intf)
  {
  	struct ds_device *dev;
  
  	dev = usb_get_intfdata(intf);
  	if (!dev)
  		return;
  
  	mutex_lock(&ds_mutex);
  	list_del(&dev->ds_entry);
  	mutex_unlock(&ds_mutex);
  
  	ds_w1_fini(dev);
  
  	usb_set_intfdata(intf, NULL);
  
  	usb_put_dev(dev->udev);
  	kfree(dev);
  }
  
  module_usb_driver(ds_driver);
  
  MODULE_LICENSE("GPL");
  MODULE_AUTHOR("Evgeniy Polyakov <zbr@ioremap.net>");
  MODULE_DESCRIPTION("DS2490 USB <-> W1 bus master driver (DS9490*)");