shuttle_usbat.c

usb 子设备程序 支持sd卡 mouse keyboard 的最单单的驱动程序 gcc编译 支持

/* Driver for SCM Microsystems (a.k.a. Shuttle) USB-ATAPI cable
 *
 * $Id: shuttle_usbat.c,v 1.1.1.1 2007/06/12 07:27:09 eyryu Exp $
 *
 * Current development and maintenance by:
 *   (c) 2000, 2001 Robert Baruch ([e-mail])
 *   (c) 2004, 2005 Daniel Drake <[e-mail]>
 *
 * Developed with the assistance of:
 *   (c) 2002 Alan Stern <[e-mail]>
 *
 * Flash support based on earlier work by:
 *   (c) 2002 Thomas Kreiling <[e-mail]>
 *
 * Many originally ATAPI devices were slightly modified to meet the USB
 * market by using some kind of translation from ATAPI to USB on the host,
 * and the peripheral would translate from USB back to ATAPI.
 *
 * SCM Microsystems (www.scmmicro.com) makes a device, sold to OEM's only, 
 * which does the USB-to-ATAPI conversion.  By obtaining the data sheet on
 * their device under nondisclosure agreement, I have been able to write
 * this driver for Linux.
 *
 * The chip used in the device can also be used for EPP and ISA translation
 * as well. This driver is only guaranteed to work with the ATAPI
 * translation.
 *
 * See the Kconfig help text for a list of devices known to be supported by
 * this driver.
 *
 * 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, 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.,
 * 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/cdrom.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>

#include "usb.h"
#include "transport.h"
#include "protocol.h"
#include "debug.h"
#include "shuttle_usbat.h"

#define short_pack(LSB,MSB) ( ((u16)(LSB)) | ( ((u16)(MSB))<<8 ) )
#define LSB_of(s) ((s)&0xFF)
#define MSB_of(s) ((s)>>8)

static int transferred = 0;

static int usbat_flash_transport(struct scsi_cmnd * srb, struct us_data *us);
static int usbat_hp8200e_transport(struct scsi_cmnd *srb, struct us_data *us);

/*
 * Convenience function to produce an ATA read/write sectors command
 * Use cmd=0x20 for read, cmd=0x30 for write
 */
static void usbat_pack_ata_sector_cmd(unsigned char *buf,
					unsigned char thistime,
					u32 sector, unsigned char cmd)
{
	buf[0] = 0;
	buf[1] = thistime;
	buf[2] = sector & 0xFF;
	buf[3] = (sector >>  8) & 0xFF;
	buf[4] = (sector >> 16) & 0xFF;
	buf[5] = 0xE0 | ((sector >> 24) & 0x0F);
	buf[6] = cmd;
}

/*
 * Convenience function to get the device type (flash or hp8200)
 */
static int usbat_get_device_type(struct us_data *us)
{
	return ((struct usbat_info*)us->extra)->devicetype;
}

/*
 * Read a register from the device
 */
static int usbat_read(struct us_data *us,
		      unsigned char access,
		      unsigned char reg,
		      unsigned char *content)
{
	return usb_stor_ctrl_transfer(us,
		us->recv_ctrl_pipe,
		access | USBAT_CMD_READ_REG,
		0xC0,
		(u16)reg,
		0,
		content,
		1);
}

/*
 * Write to a register on the device
 */
static int usbat_write(struct us_data *us,
		       unsigned char access,
		       unsigned char reg,
		       unsigned char content)
{
	return usb_stor_ctrl_transfer(us,
		us->send_ctrl_pipe,
		access | USBAT_CMD_WRITE_REG,
		0x40,
		short_pack(reg, content),
		0,
		NULL,
		0);
}

/*
 * Convenience function to perform a bulk read
 */
static int usbat_bulk_read(struct us_data *us,
			   unsigned char *data,
			   unsigned int len,
			   int use_sg)
{
	if (len == 0)
		return USB_STOR_XFER_GOOD;

	US_DEBUGP("usbat_bulk_read: len = %d\n", len);
	return usb_stor_bulk_transfer_sg(us, us->recv_bulk_pipe, data, len, use_sg, NULL);
}

/*
 * Convenience function to perform a bulk write
 */
static int usbat_bulk_write(struct us_data *us,
			    unsigned char *data,
			    unsigned int len,
			    int use_sg)
{
	if (len == 0)
		return USB_STOR_XFER_GOOD;

	US_DEBUGP("usbat_bulk_write:  len = %d\n", len);
	return usb_stor_bulk_transfer_sg(us, us->send_bulk_pipe, data, len, use_sg, NULL);
}

/*
 * Some USBAT-specific commands can only be executed over a command transport
 * This transport allows one (len=8) or two (len=16) vendor-specific commands
 * to be executed.
 */
static int usbat_execute_command(struct us_data *us,
								 unsigned char *commands,
								 unsigned int len)
{
	return usb_stor_ctrl_transfer(us, us->send_ctrl_pipe,
								  USBAT_CMD_EXEC_CMD, 0x40, 0, 0,
								  commands, len);
}

/*
 * Read the status register
 */
static int usbat_get_status(struct us_data *us, unsigned char *status)
{
	int rc;
	rc = usbat_read(us, USBAT_ATA, USBAT_ATA_STATUS, status);

	US_DEBUGP("usbat_get_status: 0x%02X\n", (unsigned short) (*status));
	return rc;
}

/*
 * Check the device status
 */
static int usbat_check_status(struct us_data *us)
{
	unsigned char *reply = us->iobuf;
	int rc;

	if (!us)
		return USB_STOR_TRANSPORT_ERROR;

	rc = usbat_get_status(us, reply);
	if (rc != USB_STOR_XFER_GOOD)
		return USB_STOR_TRANSPORT_FAILED;

	/* error/check condition (0x51 is ok) */
	if (*reply & 0x01 && *reply != 0x51)
		return USB_STOR_TRANSPORT_FAILED;

	/* device fault */
	if (*reply & 0x20)
		return USB_STOR_TRANSPORT_FAILED;

	return USB_STOR_TRANSPORT_GOOD;
}

/*
 * Stores critical information in internal registers in prepartion for the execution
 * of a conditional usbat_read_blocks or usbat_write_blocks call.
 */
static int usbat_set_shuttle_features(struct us_data *us,
				      unsigned char external_trigger,
				      unsigned char epp_control,
				      unsigned char mask_byte,
				      unsigned char test_pattern,
				      unsigned char subcountH,
				      unsigned char subcountL)
{
	unsigned char *command = us->iobuf;

	command[0] = 0x40;
	command[1] = USBAT_CMD_SET_FEAT;

	/*
	 * The only bit relevant to ATA access is bit 6
	 * which defines 8 bit data access (set) or 16 bit (unset)
	 */
	command[2] = epp_control;

	/*
	 * If FCQ is set in the qualifier (defined in R/W cmd), then bits U0, U1,
	 * ET1 and ET2 define an external event to be checked for on event of a
	 * _read_blocks or _write_blocks operation. The read/write will not take
	 * place unless the defined trigger signal is active.
	 */
	command[3] = external_trigger;

	/*
	 * The resultant byte of the mask operation (see mask_byte) is compared for
	 * equivalence with this test pattern. If equal, the read/write will take
	 * place.
	 */
	command[4] = test_pattern;

	/*
	 * This value is logically ANDed with the status register field specified
	 * in the read/write command.
	 */
	command[5] = mask_byte;

	/*
	 * If ALQ is set in the qualifier, this field contains the address of the
	 * registers where the byte count should be read for transferring the data.
	 * If ALQ is not set, then this field contains the number of bytes to be
	 * transferred.
	 */
	command[6] = subcountL;
	command[7] = subcountH;

	return usbat_execute_command(us, command, 8);
}

/*
 * Block, waiting for an ATA device to become not busy or to report
 * an error condition.
 */
static int usbat_wait_not_busy(struct us_data *us, int minutes)
{
	int i;
	int result;
	unsigned char *status = us->iobuf;

	/* Synchronizing cache on a CDR could take a heck of a long time,
	 * but probably not more than 10 minutes or so. On the other hand,
	 * doing a full blank on a CDRW at speed 1 will take about 75
	 * minutes!
	 */

	for (i=0; i<1200+minutes*60; i++) {

 		result = usbat_get_status(us, status);

		if (result!=USB_STOR_XFER_GOOD)
			return USB_STOR_TRANSPORT_ERROR;
		if (*status & 0x01) { /* check condition */
			result = usbat_read(us, USBAT_ATA, 0x10, status);
			return USB_STOR_TRANSPORT_FAILED;
		}
		if (*status & 0x20) /* device fault */
			return USB_STOR_TRANSPORT_FAILED;

		if ((*status & 0x80)==0x00) { /* not busy */
			US_DEBUGP("Waited not busy for %d steps\n", i);
			return USB_STOR_TRANSPORT_GOOD;
		}

		if (i<500)
			msleep(10); /* 5 seconds */
		else if (i<700)
			msleep(50); /* 10 seconds */
		else if (i<1200)
			msleep(100); /* 50 seconds */
		else
			msleep(1000); /* X minutes */
	}

	US_DEBUGP("Waited not busy for %d minutes, timing out.\n",
		minutes);
	return USB_STOR_TRANSPORT_FAILED;
}

/*
 * Read block data from the data register
 */
static int usbat_read_block(struct us_data *us,
			    unsigned char *content,
			    unsigned short len,
			    int use_sg)
{
	int result;
	unsigned char *command = us->iobuf;

	if (!len)
		return USB_STOR_TRANSPORT_GOOD;

	command[0] = 0xC0;
	command[1] = USBAT_ATA | USBAT_CMD_READ_BLOCK;
	command[2] = USBAT_ATA_DATA;
	command[3] = 0;
	command[4] = 0;
	command[5] = 0;
	command[6] = LSB_of(len);
	command[7] = MSB_of(len);

	result = usbat_execute_command(us, command, 8);
	if (result != USB_STOR_XFER_GOOD)
		return USB_STOR_TRANSPORT_ERROR;

	result = usbat_bulk_read(us, content, len, use_sg);
	return (result == USB_STOR_XFER_GOOD ?
			USB_STOR_TRANSPORT_GOOD : USB_STOR_TRANSPORT_ERROR);
}

/*
 * Write block data via the data register
 */
static int usbat_write_block(struct us_data *us,
			     unsigned char access,
			     unsigned char *content,
			     unsigned short len,
			     int minutes,
			     int use_sg)
{
	int result;
	unsigned char *command = us->iobuf;

	if (!len)
		return USB_STOR_TRANSPORT_GOOD;

	command[0] = 0x40;
	command[1] = access | USBAT_CMD_WRITE_BLOCK;
	command[2] = USBAT_ATA_DATA;
	command[3] = 0;
	command[4] = 0;
	command[5] = 0;
	command[6] = LSB_of(len);
	command[7] = MSB_of(len);

	result = usbat_execute_command(us, command, 8);

	if (result != USB_STOR_XFER_GOOD)
		return USB_STOR_TRANSPORT_ERROR;

	result = usbat_bulk_write(us, content, len, use_sg);
	if (result != USB_STOR_XFER_GOOD)
		return USB_STOR_TRANSPORT_ERROR;

	return usbat_wait_not_busy(us, minutes);
}

/*
 * Process read and write requests
 */
static int usbat_hp8200e_rw_block_test(struct us_data *us,
				       unsigned char access,
				       unsigned char *registers,
				       unsigned char *data_out,
				       unsigned short num_registers,
				       unsigned char data_reg,
				       unsigned char status_reg,
				       unsigned char timeout,
				       unsigned char qualifier,
				       int direction,
				       unsigned char *content,
				       unsigned short len,
				       int use_sg,
				       int minutes)
{
	int result;
	unsigned int pipe = (direction == DMA_FROM_DEVICE) ?
			us->recv_bulk_pipe : us->send_bulk_pipe;

	unsigned char *command = us->iobuf;
	int i, j;
	int cmdlen;
	unsigned char *data = us->iobuf;
	unsigned char *status = us->iobuf;

	BUG_ON(num_registers > US_IOBUF_SIZE/2);

	for (i=0; i<20; i++) {

		/*
		 * The first time we send the full command, which consists
		 * of downloading the SCSI command followed by downloading
		 * the data via a write-and-test.  Any other time we only
		 * send the command to download the data -- the SCSI command
		 * is still 'active' in some sense in the device.
		 * 
		 * We're only going to try sending the data 10 times. After
		 * that, we just return a failure.
		 */

		if (i==0) {
			cmdlen = 16;
			/*
			 * Write to multiple registers
			 * Not really sure the 0x07, 0x17, 0xfc, 0xe7 is
			 * necessary here, but that's what came out of the
			 * trace every single time.
			 */
			command[0] = 0x40;