drivers/usb/storage/realtek_cr.c

/* Driver for Realtek RTS51xx USB card reader
 *
 * Copyright(c) 2009 Realtek Semiconductor Corp. All rights reserved.  
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 * Author:
 *   wwang (wei_wang@realsil.com.cn)
 *   No. 450, Shenhu Road, Suzhou Industry Park, Suzhou, China
 */

#include <linux/module.h>
#include <linux/blkdev.h>
#include <linux/kthread.h>
#include <linux/sched.h>
#include <linux/workqueue.h>
#include <linux/kernel.h>
#include <linux/version.h>

#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <linux/cdrom.h>

#include <linux/usb.h>
#include <linux/usb_usual.h>

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

MODULE_DESCRIPTION("Driver for Realtek USB Card Reader");
MODULE_AUTHOR("wwang <wei_wang@realsil.com.cn>");
MODULE_LICENSE("GPL");
MODULE_VERSION("1.02");

static int ss_en = 1;
module_param(ss_en, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(ss_en, "enable selective suspend");

static int ss_delay = 50;
module_param(ss_delay, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(ss_delay, "seconds to delay before entering selective suspend");

static int needs_remote_wakeup = 0;
module_param(needs_remote_wakeup, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(needs_remote_wakeup, "ss state needs remote wakeup supported");

static int auto_delink_en = 1;
module_param(auto_delink_en, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(auto_delink_en, "enable auto delink");

enum CHIP_STAT	{STAT_INIT, STAT_IDLE, STAT_RUN, STAT_SS_PRE, STAT_SS, STAT_SUSPEND};

struct rts51x_status {
	u16 vid;
	u16 pid;
	u8 cur_lun;
	u8 card_type;
	u8 total_lun;
	u16 fw_ver;
	u8 phy_exist;
	u8 multi_flag;
	u8 multi_card;
	u8 log_exist;
	union {
		u8 detailed_type1;
		u8 detailed_type2;
	} detailed_type;
	u8 function[2];
};

struct rts51x_chip {
	u16 			vendor_id;
	u16 			product_id;
	char 			max_lun;
	
	int 			ss_counter;
	int 			idle_counter;
	enum CHIP_STAT		chip_stat;
	
	int			resume_from_scsi;
	
	struct rts51x_status	*status;
	int			status_len;
	u8			lun_ready;
	
	u32			flag;
	
	struct task_struct	*polling_thread; /* the polling thread   */
};

// flag definition
#define FLIDX_AUTO_DELINK		0x01

#define POLLING_INTERVAL		50	// 50ms
#define IDLE_MAX_COUNT			10

#define SCSI_LUN(srb)			(srb)->device->lun

// Bit Operation
#define SET_BIT(data, idx)		(data) |= 1 << (idx)
#define CLR_BIT(data, idx)		(data) &= ~(1 << (idx))
#define CHK_BIT(data, idx)		((data) & (1 << (idx)))

#define SET_LUN_READY(chip, lun)	((chip)->lun_ready |= ((u8)1 << (lun)))
#define CLR_LUN_READY(chip, lun)	((chip)->lun_ready &= ~((u8)1 << (lun)))
#define CHK_LUN_READY(chip, lun)	((chip)->lun_ready & ((u8)1 << (lun)))

#define SET_AUTO_DELINK(chip)		((chip)->flag |= FLIDX_AUTO_DELINK)
#define CLR_AUTO_DELINK(chip)		((chip)->flag &= ~FLIDX_AUTO_DELINK)
#define CHK_AUTO_DELINK(chip)		((chip)->flag & FLIDX_AUTO_DELINK)

#define RTS51X_GET_VID(chip)		((chip)->vendor_id)
#define RTS51X_GET_PID(chip)		((chip)->product_id)

#define FW_VERSION(chip)		((chip)->status[0].fw_ver)
#define STATUS_LEN(chip)		((chip)->status_len)

// Check card reader function
#define SUPPORT_DETAILED_TYPE1(chip)	CHK_BIT((chip)->status[0].function[0], 1)
#define SUPPORT_OT(chip)		CHK_BIT((chip)->status[0].function[0], 2)
#define SUPPORT_OC(chip)		CHK_BIT((chip)->status[0].function[0], 3)
#define SUPPORT_AUTO_DELINK(chip)	CHK_BIT((chip)->status[0].function[0], 4)
#define SUPPORT_SDIO(chip)		CHK_BIT((chip)->status[0].function[1], 0)
#define SUPPORT_DETAILED_TYPE2(chip)	CHK_BIT((chip)->status[0].function[1], 1)

#define RTS51X_SET_STAT(chip, stat)			\
do {							\
	if ((stat) != STAT_IDLE) {			\
		(chip)->idle_counter = 0;		\
	}						\
	(chip)->chip_stat = (enum CHIP_STAT)(stat);	\
} while (0)
#define RTS51X_CHK_STAT(chip, stat)	((chip)->chip_stat == (stat))
#define RTS51X_GET_STAT(chip)		((chip)->chip_stat)

#define CHECK_PID(chip, pid)		(RTS51X_GET_PID(chip) == (pid))
#define CHECK_FW_VER(chip, fw_ver)	(FW_VERSION(chip) == (fw_ver))

#define GET_PM_USAGE_CNT(us)		atomic_read(&((us)->pusb_intf->pm_usage_cnt))
#define SET_PM_USAGE_CNT(us, cnt)	atomic_set(&((us)->pusb_intf->pm_usage_cnt), (cnt))

#define wait_timeout_x(task_state,msecs)	\
do {						\
	set_current_state((task_state));	\
	schedule_timeout((msecs) * HZ / 1000);	\
} while (0)

#define wait_timeout(msecs)		wait_timeout_x(TASK_INTERRUPTIBLE, (msecs))

#if  LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 33)
static inline void usb_autopm_enable(struct usb_interface *intf)
{
	atomic_set(&intf->pm_usage_cnt, 1);
	usb_autopm_put_interface(intf);
}

static inline void usb_autopm_disable(struct usb_interface *intf)
{
	atomic_set(&intf->pm_usage_cnt, 0);
	usb_autopm_get_interface(intf);
}
#endif

static int init_realtek_cr(struct us_data *us);

/*
 * The table of devices
 */
#define UNUSUAL_DEV(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax, \
		    vendorName, productName, useProtocol, useTransport, \
		    initFunction, flags) \
{ USB_DEVICE_VER(id_vendor, id_product, bcdDeviceMin, bcdDeviceMax), \
  .driver_info = (flags)|(USB_US_TYPE_STOR<<24) }

struct usb_device_id realtek_cr_ids[] = {
#	include "unusual_realtek.h"
	{ }		/* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, realtek_cr_ids);

#undef UNUSUAL_DEV

/*
 * The flags table
 */
#define UNUSUAL_DEV(idVendor, idProduct, bcdDeviceMin, bcdDeviceMax, \
		    vendor_name, product_name, use_protocol, use_transport, \
		    init_function, Flags) \
{ \
	.vendorName = vendor_name,	\
	.productName = product_name,	\
	.useProtocol = use_protocol,	\
	.useTransport = use_transport,	\
	.initFunction = init_function,	\
}

static struct us_unusual_dev realtek_cr_unusual_dev_list[] = {
#	include "unusual_realtek.h"
	{ }		/* Terminating entry */
};

#undef UNUSUAL_DEV

static int rts51x_bulk_transport(struct us_data *us, u8 lun, 
				 u8 *cmd, int cmd_len, u8 *buf, int buf_len,
				 enum dma_data_direction dir, int *act_len)
{
	struct bulk_cb_wrap *bcb = (struct bulk_cb_wrap *) us->iobuf;
	struct bulk_cs_wrap *bcs = (struct bulk_cs_wrap *) us->iobuf;
	int result;
	unsigned int residue;
	unsigned int cswlen;
	unsigned int cbwlen = US_BULK_CB_WRAP_LEN;

	/* set up the command wrapper */
	bcb->Signature = cpu_to_le32(US_BULK_CB_SIGN);
	bcb->DataTransferLength = cpu_to_le32(buf_len);
	bcb->Flags = (dir == DMA_FROM_DEVICE) ? 1 << 7 : 0;
	bcb->Tag = ++us->tag;
	bcb->Lun = lun;
	bcb->Length = cmd_len;

	/* copy the command payload */
	memset(bcb->CDB, 0, sizeof(bcb->CDB));
	memcpy(bcb->CDB, cmd, bcb->Length);

	/* send it to out endpoint */
	result = usb_stor_bulk_transfer_buf(us, us->send_bulk_pipe,
				bcb, cbwlen, NULL);
	if (result != USB_STOR_XFER_GOOD)
		return USB_STOR_TRANSPORT_ERROR;

	/* DATA STAGE */
	/* send/receive data payload, if there is any */

	if (buf && buf_len) {
		unsigned int pipe = (dir == DMA_FROM_DEVICE) ? 
				us->recv_bulk_pipe : us->send_bulk_pipe;
		result = usb_stor_bulk_transfer_buf(us, pipe, 
				buf, buf_len, NULL);
		if (result == USB_STOR_XFER_ERROR)
			return USB_STOR_TRANSPORT_ERROR;
	}

	/* get CSW for device status */
	result = usb_stor_bulk_transfer_buf(us, us->recv_bulk_pipe,
				bcs, US_BULK_CS_WRAP_LEN, &cswlen);
	if (result != USB_STOR_XFER_GOOD)
		return USB_STOR_TRANSPORT_ERROR;

	/* check bulk status */
	if (bcs->Signature != cpu_to_le32(US_BULK_CS_SIGN)) {
		US_DEBUGP("Signature mismatch: got %08X, expecting %08X\n",
			  le32_to_cpu(bcs->Signature),
			  US_BULK_CS_SIGN);
		return USB_STOR_TRANSPORT_ERROR;
	}
	
	residue = bcs->Residue;
	if (bcs->Tag != us->tag) {
		return USB_STOR_TRANSPORT_ERROR;
	}
	
	/* try to compute the actual residue, based on how much data
	 * was really transferred and what the device tells us */
	if (residue) {
		residue = residue < buf_len ? residue : buf_len;
	}
	
	if (act_len) {
		*act_len = buf_len - residue;
	}

	/* based on the status code, we report good or bad */
	switch (bcs->Status) {
		case US_BULK_STAT_OK:
			/* command good -- note that data could be short */
			return USB_STOR_TRANSPORT_GOOD;

		case US_BULK_STAT_FAIL:
			/* command failed */
			return USB_STOR_TRANSPORT_FAILED;

		case US_BULK_STAT_PHASE:
			/* phase error -- note that a transport reset will be
			 * invoked by the invoke_transport() function
			 */
			return USB_STOR_TRANSPORT_ERROR;
	}

	/* we should never get here, but if we do, we're in trouble */
	return USB_STOR_TRANSPORT_ERROR;
}

/* Determine what the maximum LUN supported is */
static int rts51x_get_max_lun(struct us_data *us)
{
	int result;

	/* issue the command */
	us->iobuf[0] = 0;
	result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
				 US_BULK_GET_MAX_LUN, 
				 USB_DIR_IN | USB_TYPE_CLASS | 
				 USB_RECIP_INTERFACE,
				 0, us->ifnum, us->iobuf, 1, 10*HZ);

	US_DEBUGP("GetMaxLUN command result is %d, data is %d\n", 
		  result, us->iobuf[0]);

	/* if we have a successful request, return the result */
	if (result > 0)
		return us->iobuf[0];

	return 0;
}

static int rts51x_read_mem(struct us_data *us, u16 addr, u8 *data, u16 len)
{
	int retval;
	u8 cmnd[12] = {0};

	US_DEBUGP("%s, addr = 0x%x, len = %d\n", __FUNCTION__, addr, len);

	cmnd[0] = 0xF0;
	cmnd[1] = 0x0D;
	cmnd[2] = (u8)(addr >> 8);
	cmnd[3] = (u8)addr;
	cmnd[4] = (u8)(len >> 8);
	cmnd[5] = (u8)len;

	retval = rts51x_bulk_transport(us, 0, cmnd, 12, data, len, DMA_FROM_DEVICE, NULL);
	if (retval != USB_STOR_TRANSPORT_GOOD) {
		return -EIO;
	}
	
	return 0;
}

static int rts51x_write_mem(struct us_data *us, u16 addr, u8 *data, u16 len)
{
	int retval;
	u8 cmnd[12] = {0};

	US_DEBUGP("%s, addr = 0x%x, len = %d\n", __FUNCTION__, addr, len);

	cmnd[0] = 0xF0;
	cmnd[1] = 0x0E;
	cmnd[2] = (u8)(addr >> 8);
	cmnd[3] = (u8)addr;
	cmnd[4] = (u8)(len >> 8);
	cmnd[5] = (u8)len;

	retval = rts51x_bulk_transport(us, 0, cmnd, 12, data, len, DMA_TO_DEVICE, NULL);
	if (retval != USB_STOR_TRANSPORT_GOOD) {
		return -EIO;
	}
	
	return 0;
}

static int rts51x_read_status(struct us_data *us, u8 lun, u8 *status, int len, int *actlen)
{
	int retval;
	u8 cmnd[12] = {0};

	US_DEBUGP("%s, lun = %d\n", __FUNCTION__, lun);

	cmnd[0] = 0xF0;
	cmnd[1] = 0x09;

	retval = rts51x_bulk_transport(us, lun, cmnd, 12, status, len, DMA_FROM_DEVICE, actlen);
	if (retval != USB_STOR_TRANSPORT_GOOD) {
		return -EIO;
	}
	
	return 0;
}

static int rts51x_test_unit_ready(struct us_data *us, u8 lun)
{
	int retval;
	u8 cmnd[12] = {0};

	US_DEBUGP("%s, lun = %d\n", __FUNCTION__, lun);

	cmnd[0] = TEST_UNIT_READY;

	retval = rts51x_bulk_transport(us, lun, cmnd, 12, NULL, 0, DMA_NONE, NULL);
	if (retval != USB_STOR_TRANSPORT_GOOD) {
		return -EIO;
	}
	
	return 0;
}

static void rts51x_reset_card(struct us_data *us, u8 lun)
{
	US_DEBUGP("Try to reset lun %d\n", lun);
	rts51x_test_unit_ready(us, lun);
}

static int rts51x_check_status(struct us_data *us, u8 lun)
{
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);
	int retval;
	u8 buf[16];
	
	retval = rts51x_read_status(us, lun, buf, 16, &(chip->status_len));
	if (retval < 0) {
		return -EIO;
	}
	
	US_DEBUGP("chip->status_len = %d\n", chip->status_len);
	
	chip->status[lun].vid = ((u16)buf[0] << 8) | buf[1];
	chip->status[lun].pid = ((u16)buf[2] << 8) | buf[3];
	chip->status[lun].cur_lun = buf[4];
	chip->status[lun].card_type = buf[5];
	chip->status[lun].total_lun = buf[6];
	chip->status[lun].fw_ver = ((u16)buf[7] << 8) | buf[8];
	chip->status[lun].phy_exist = buf[9];
	chip->status[lun].multi_flag = buf[10];
	chip->status[lun].multi_card = buf[11];
	chip->status[lun].log_exist = buf[12];
	if (chip->status_len == 16) {
		chip->status[lun].detailed_type.detailed_type1 = buf[13];
		chip->status[lun].function[0] = buf[14];
		chip->status[lun].function[1] = buf[15];
	}
	
	return 0;
}

static int enable_oscillator(struct us_data *us)
{
	int retval;
	u8 value;
	
	retval = rts51x_read_mem(us, 0xFE77, &value, 1);
	if (retval < 0) {
		return -EIO;
	}
	
	value |= 0x04;
	retval = rts51x_write_mem(us, 0xFE77, &value, 1);
	if (retval < 0) {
		return -EIO;
	}
	
	retval = rts51x_read_mem(us, 0xFE77, &value, 1);
	if (retval < 0) {
		return -EIO;
	}
	
	if (!(value & 0x04)) {
		return -EIO;
	}
	
	return 0;
}

static int do_config_autodelink(struct us_data *us, int enable, int force)
{
	int retval;
	u8 value;
	
	retval = rts51x_read_mem(us, 0xFE47, &value, 1);
	if (retval < 0) {
		return -EIO;
	}
	
	if (enable) {
		if (force) {
			value |= 0x03;
		} else {
			value |= 0x01;
		}
	} else {
		value &= ~0x03;
	}
	
	US_DEBUGP("In %s,set 0xfe47 to 0x%x\n", __FUNCTION__, value);
	
	retval = rts51x_write_mem(us, 0xFE47, &value, 1);
	if (retval < 0) {
		return -EIO;
	}
	
	return 0;
}

static int config_autodelink_after_power_on(struct us_data *us)
{
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);
	int retval;
	u8 value;
	
	if (!CHK_AUTO_DELINK(chip)) {
		return 0;	
	}
	
	retval = rts51x_read_mem(us, 0xFE47, &value, 1);
	if (retval < 0) {
		return -EIO;
	}
	
	if (auto_delink_en) {
		CLR_BIT(value, 0);
		CLR_BIT(value, 1);
		SET_BIT(value, 2);
		
		if (CHECK_PID(chip, 0x0138) && CHECK_FW_VER(chip, 0x3882)) {
			CLR_BIT(value, 2);
		}
		
		SET_BIT(value, 7);
		
		retval = rts51x_write_mem(us, 0xFE47, &value, 1);
		if (retval < 0) {
			return -EIO;
		}
		
		retval = enable_oscillator(us);
		if (retval == 0) {
			(void)do_config_autodelink(us, 1, 0);
		}
	} else {
		// Autodelink controlled by firmware
		
		SET_BIT(value, 2);
		
		if (CHECK_PID(chip, 0x0138) && CHECK_FW_VER(chip, 0x3882)) {
			CLR_BIT(value, 2);
		}
		
		if ((CHECK_FW_VER(chip, 0x5889) && CHECK_PID(chip, 0x0159)) || 
			(CHECK_FW_VER(chip, 0x3880) && CHECK_PID(chip, 0x0138))) {
			CLR_BIT(value, 0);
			CLR_BIT(value, 7);
		}
		
		retval = rts51x_write_mem(us, 0xFE47, &value, 1);
		if (retval < 0) {
			return -EIO;
		}
		
		if (CHECK_FW_VER(chip, 0x5888) && CHECK_PID(chip, 0x0159)) {
			value = 0xFF;
			retval = rts51x_write_mem(us, 0xFE79, &value, 1);
			if (retval < 0) {
				return -EIO;
			}
			
			value = 0x01;
			retval = rts51x_write_mem(us, 0x48, &value, 1);
			if (retval < 0) {
				return -EIO;
			}
		}
	}
	
	return 0;
}

static int config_autodelink_before_power_down(struct us_data *us)
{
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);
	int retval;
	u8 value;
	
	if (!CHK_AUTO_DELINK(chip)) {
		return 0;	
	}
	
	if (auto_delink_en) {
		retval = rts51x_read_mem(us, 0xFE77, &value, 1);
		if (retval < 0) {
			return -EIO;
		}
		
		SET_BIT(value, 2);
		retval = rts51x_write_mem(us, 0xFE77, &value, 1);
		if (retval < 0) {
			return -EIO;
		}
		
		if (CHECK_FW_VER(chip, 0x5888) && CHECK_PID(chip, 0x0159)) {
			value = 0x01;
			retval = rts51x_write_mem(us, 0x48, &value, 1);
			if (retval < 0) {
				return -EIO;
			}
		}
		
		retval = rts51x_read_mem(us, 0xFE47, &value, 1);
		if (retval < 0) {
			return -EIO;
		}
		
		SET_BIT(value, 0);
		if (CHECK_FW_VER(chip, 0x3882) && CHECK_PID(chip, 0x0138)) {
			SET_BIT(value, 2);
		}
		retval = rts51x_write_mem(us, 0xFE77, &value, 1);
		if (retval < 0) {
			return -EIO;
		}
	} else {
		if ((CHECK_FW_VER(chip, 0x5889) && CHECK_PID(chip, 0x0159)) || 
			(CHECK_FW_VER(chip, 0x3880) && CHECK_PID(chip, 0x0138)) || 
			(CHECK_FW_VER(chip, 0x3882) && CHECK_PID(chip, 0x0138))) {
			retval = rts51x_read_mem(us, 0xFE47, &value, 1);
			if (retval < 0) {
				return -EIO;
			}
			
			if ((CHECK_FW_VER(chip, 0x5889) && CHECK_PID(chip, 0x0159)) || 
				(CHECK_FW_VER(chip, 0x3880) && CHECK_PID(chip, 0x0138))) {
				SET_BIT(value, 0);
				SET_BIT(value, 7);
			}
			
			if (CHECK_FW_VER(chip, 0x3882) && CHECK_PID(chip, 0x0138)) {
				SET_BIT(value, 2);
			}
			
			retval = rts51x_write_mem(us, 0xFE47, &value, 1);
			if (retval < 0) {
				return -EIO;
			}
		}
		
		if (CHECK_FW_VER(chip, 0x5888) && CHECK_PID(chip, 0x0159)) {
			value = 0x01;
			retval = rts51x_write_mem(us, 0x48, &value, 1);
			if (retval < 0) {
				return -EIO;
			}
		}
	}
	
	return 0;
}

static void rts51x_polling_func(struct us_data *us)
{
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);
			
	/* lock the device pointers */
	mutex_lock(&(us->dev_mutex));
	
	if (RTS51X_CHK_STAT(chip, STAT_SS) || RTS51X_CHK_STAT(chip, STAT_SS_PRE)) {
		/* unlock the device pointers */
		mutex_unlock(&(us->dev_mutex));
		return;
	}

#ifdef CONFIG_PM
	if (ss_en) {
		if (RTS51X_CHK_STAT(chip, STAT_IDLE)) {
			if (chip->ss_counter < (ss_delay * 1000 / POLLING_INTERVAL)) {
				chip->ss_counter ++;
			} else {
				US_DEBUGP("Ready to enter SS state\n");
				RTS51X_SET_STAT(chip, STAT_SS_PRE);   // Prepare SS state
				
				/* unlock the device pointers */
				mutex_unlock(&(us->dev_mutex));
				usb_autopm_enable(us->pusb_intf);
				return;
			}
		} else {
			chip->ss_counter = 0;
		}
	}
#endif
	
	if (chip->idle_counter < IDLE_MAX_COUNT) {
		chip->idle_counter ++;
	} else {
		if (!RTS51X_CHK_STAT(chip, STAT_IDLE)) {
			US_DEBUGP("Idle state\n");
			RTS51X_SET_STAT(chip, STAT_IDLE);
		}
	}
	
	/* unlock the device pointers */
	mutex_unlock(&(us->dev_mutex));
}

static int rts51x_polling_thread(void * __us)
{
	struct us_data *us = (struct us_data *)__us;
	
	// Wait until SCSI scan finished
	wait_timeout(10 * HZ);

	for(;;) {
		wait_timeout(POLLING_INTERVAL);
		
		/* if the device has disconnected, we are free to exit */
		if (kthread_should_stop()) {
			printk(KERN_INFO "Stop polling thread!\n");
			break;
		}
		
		rts51x_polling_func(us);

	} /* for (;;) */

	__set_current_state(TASK_RUNNING);
	return 0;
}

#ifdef CONFIG_PM
int realtek_cr_suspend(struct usb_interface *iface, pm_message_t message)
{
	struct us_data *us = usb_get_intfdata(iface);
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);

	US_DEBUGP("%s, message.event = 0x%x\n", __func__, message.event);
	
	/* Wait until no command is running */
	mutex_lock(&us->dev_mutex);
	
	if (message.event == PM_EVENT_AUTO_SUSPEND) {
		US_DEBUGP("Enter SS state");
		chip->resume_from_scsi = 0;
		RTS51X_SET_STAT(chip, STAT_SS);
	} else {
		US_DEBUGP("Enter SUSPEND state");
		RTS51X_SET_STAT(chip, STAT_SUSPEND);
	}
	(void)config_autodelink_before_power_down(us);

	/* When runtime PM is working, we'll set a flag to indicate
	* whether we should autoresume when a SCSI request arrives. */

	mutex_unlock(&us->dev_mutex);

	return 0;
}

int realtek_cr_resume(struct usb_interface *iface)
{
	struct us_data *us = usb_get_intfdata(iface);
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);

	US_DEBUGP("%s\n", __func__);
	
	if (!RTS51X_CHK_STAT(chip, STAT_SS) || !chip->resume_from_scsi) {
		mutex_lock(&us->dev_mutex);

		if (GET_PM_USAGE_CNT(us) <= 0) {
			// Remote wake up, increase pm_usage_cnt
			US_DEBUGP("Incr pm_usage_cnt\n");
			SET_PM_USAGE_CNT(us, 1);
		}

		(void)config_autodelink_after_power_on(us);

		RTS51X_SET_STAT(chip, STAT_RUN);
	
		mutex_unlock(&us->dev_mutex);
	}

	return 0;
}
#endif

static void realtek_cr_destructor(void *extra) 
{
	struct rts51x_chip *chip = (struct rts51x_chip *)extra;

	if (!chip)
		return;
	
	if (chip->polling_thread) {
		kthread_stop(chip->polling_thread);
		printk(KERN_INFO "Polling thread stopped!\n");
	}

	if (chip->status) {
		kfree(chip->status);
	}
}

static int init_realtek_cr(struct us_data *us)
{
	struct rts51x_chip *chip;
	int size, i, retval;
	struct task_struct *th;
	
	chip = kzalloc(sizeof(struct rts51x_chip), GFP_KERNEL);
	if (!chip)
		return -ENOMEM;
	
	us->extra = chip;
	us->extra_destructor = realtek_cr_destructor;
	
	us->max_lun = chip->max_lun = rts51x_get_max_lun(us);
	
	US_DEBUGP("chip->max_lun = %d\n", chip->max_lun);
	
	size = (chip->max_lun + 1) * sizeof(struct rts51x_status);
	chip->status = (struct rts51x_status *)kzalloc(size, GFP_KERNEL);
	if (!chip->status) {
		goto INIT_FAIL;
	}
	
	for (i = 0; i <= (int)(chip->max_lun); i++) {
		retval = rts51x_check_status(us, (u8)i);
		if (retval < 0) {
			goto INIT_FAIL;
		}
	}
	
	if (CHECK_FW_VER(chip, 0x5888) || CHECK_FW_VER(chip, 0x5889) || 
			CHECK_FW_VER(chip, 0x5901)) {
		SET_AUTO_DELINK(chip);
	}
	if (STATUS_LEN(chip) == 16) {
		if (SUPPORT_AUTO_DELINK(chip)) {
			SET_AUTO_DELINK(chip);
		}
	}
	
	US_DEBUGP("chip->flag = 0x%x\n", chip->flag);
	
	(void)config_autodelink_after_power_on(us);
	
#ifdef CONFIG_PM
	if (ss_en) {
		us->pusb_intf->needs_remote_wakeup = needs_remote_wakeup;
		SET_PM_USAGE_CNT(us, 1);
		US_DEBUGP("pm_usage_cnt = %d\n", GET_PM_USAGE_CNT(us));
	
		// Enable autosuspend
		us->pusb_dev->autosuspend_disabled = 0;
	}
#endif
	
	/* Start up our polling thread */
	th = kthread_run(rts51x_polling_thread, us, "rts51x-polling");
	if (IS_ERR(th)) {
		printk(KERN_WARNING 
		       "Unable to start polling thread\n");
		goto INIT_FAIL;
	}
	chip->polling_thread = th;
	
	return 0;
	
INIT_FAIL:
	if (us->extra) {
		if (chip->status) {
			kfree(chip->status);
		}
		kfree(us->extra);
		us->extra = NULL;
	}
	
	return -EIO;
}

u8 media_not_present[] = {0x70, 0, 0x02, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0x3A, 0, 0, 0, 0, 0};
u8 invalid_cmd_field[] = {0x70, 0, 0x05, 0, 0, 0, 0, 10, 0, 0, 0, 0, 0x24, 0, 0, 0, 0, 0};

static int realtek_cr_transport(struct scsi_cmnd *srb, struct us_data *us)
{
	struct rts51x_chip *chip = (struct rts51x_chip *)(us->extra);
	int result;
	u8 lun = (u8)SCSI_LUN(srb);
	
	scsi_set_resid(srb, 0);

#ifdef CONFIG_PM
	if (ss_en) {
		if (srb->cmnd[0] == TEST_UNIT_READY) {
			if (RTS51X_CHK_STAT(chip, STAT_SS)) {
				if (CHK_LUN_READY(chip, lun)) {
					result = USB_STOR_TRANSPORT_GOOD;
				} else {
					memcpy(srb->sense_buffer, 
						media_not_present, US_SENSE_SIZE);
					result = USB_STOR_TRANSPORT_NO_SENSE;
				}
				goto FINISH;
			}
		} else if (srb->cmnd[0] == ALLOW_MEDIUM_REMOVAL) {
			if (RTS51X_CHK_STAT(chip, STAT_SS)) {
				int prevent = srb->cmnd[4] & 0x1;

				if (prevent) {
					memcpy(srb->sense_buffer, 
						invalid_cmd_field, US_SENSE_SIZE);
					result = USB_STOR_TRANSPORT_NO_SENSE;
				} else {
					result = USB_STOR_TRANSPORT_GOOD;
				}
				
				goto FINISH;
			}
		} else {
			if (RTS51X_CHK_STAT(chip, STAT_SS)) {
				// Wake up device
				US_DEBUGP("Try to wake up device\n");
				chip->resume_from_scsi = 1;
				usb_autopm_disable(us->pusb_intf);
				wait_timeout(3000);
				
				(void)config_autodelink_after_power_on(us);
				rts51x_reset_card(us, lun);
			}
			RTS51X_SET_STAT(chip, STAT_RUN);
		}
	} 
	else 
#endif
	{
		RTS51X_SET_STAT(chip, STAT_RUN);
	}
	
	result = usb_stor_Bulk_transport(srb, us); 
	
	if (srb->cmnd[0] == TEST_UNIT_READY) {
		if (result == USB_STOR_TRANSPORT_GOOD) {
			SET_LUN_READY(chip, lun);
		} else {
			CLR_LUN_READY(chip, lun);
		}
	}
			
FINISH:
	return result;
}

static int realtek_cr_probe(struct usb_interface *intf,
			 const struct usb_device_id *id)
{
	struct us_data *us;
	int result;

	US_DEBUGP("Probe Realtek Card Reader!\n");
	
	result = usb_stor_probe1(&us, intf, id,
			(id - realtek_cr_ids) + realtek_cr_unusual_dev_list);
	if (result)
		return result;

	us->transport_name = "Realtek";
	us->transport = realtek_cr_transport;
	us->transport_reset = usb_stor_Bulk_reset;
	us->max_lun = 0;

	result = usb_stor_probe2(us);
	return result;
}

static struct usb_driver realtek_cr_driver = {
	.name =		"ums-realtek",
	.probe =	realtek_cr_probe,
	.disconnect =	usb_stor_disconnect,
	.suspend =	realtek_cr_suspend,
	.resume =	realtek_cr_resume,
	.reset_resume =	usb_stor_reset_resume,
	.pre_reset =	usb_stor_pre_reset,
	.post_reset =	usb_stor_post_reset,
	.id_table =	realtek_cr_ids,
	.soft_unbind =	1,
};

static int __init realtek_cr_init(void)
{
	return usb_register(&realtek_cr_driver);
}

static void __exit realtek_cr_exit(void)
{
	usb_deregister(&realtek_cr_driver);
}

module_init(realtek_cr_init);
module_exit(realtek_cr_exit);