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linux/drivers/usb/storage/freecom.c
Jia-Ju Bai 2a3dae10d5 usb: storage: Replace mdelay with msleep in init_freecom 
init_freecom() is never called in atomic context.

init_freecom() is set as ".initFunction" through UNUSUAL_DEV().
And ->initFunction() is only called by usb_stor_acquire_resources(),
which is only called by usb_stor_probe2().
usb_stor_probe2() is called by *_probe() functions (like alauda_probe())
for each USB driver.
*_probe() functions are set ".probe" in struct usb_driver.
These functions are not called in atomic context.

Despite never getting called from atomic context, init_freecom()
calls mdelay() to busily wait.
This is not necessary and can be replaced with msleep() to
avoid busy waiting.

This is found by a static analysis tool named DCNS written by myself.
And I also manually check it.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-22 15:49:42 +02:00

579 lines
15 KiB
C
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// SPDX-License-Identifier: GPL-2.0+
/*
* Driver for Freecom USB/IDE adaptor
*
* Freecom v0.1:
*
* First release
*
* Current development and maintenance by:
* (C) 2000 David Brown <usb-storage@davidb.org>
*
* This driver was developed with information provided in FREECOM's USB
* Programmers Reference Guide. For further information contact Freecom
* (http://www.freecom.de/)
*/
#include <linux/module.h>
#include <scsi/scsi.h>
#include <scsi/scsi_cmnd.h>
#include "usb.h"
#include "transport.h"
#include "protocol.h"
#include "debug.h"
#include "scsiglue.h"
#define DRV_NAME "ums-freecom"
MODULE_DESCRIPTION("Driver for Freecom USB/IDE adaptor");
MODULE_AUTHOR("David Brown <usb-storage@davidb.org>");
MODULE_LICENSE("GPL");
#ifdef CONFIG_USB_STORAGE_DEBUG
static void pdump(struct us_data *us, void *ibuffer, int length);
#endif
/* Bits of HD_STATUS */
#define ERR_STAT 0x01
#define DRQ_STAT 0x08
/* All of the outgoing packets are 64 bytes long. */
struct freecom_cb_wrap {
u8 Type; /* Command type. */
u8 Timeout; /* Timeout in seconds. */
u8 Atapi[12]; /* An ATAPI packet. */
u8 Filler[50]; /* Padding Data. */
};
struct freecom_xfer_wrap {
u8 Type; /* Command type. */
u8 Timeout; /* Timeout in seconds. */
__le32 Count; /* Number of bytes to transfer. */
u8 Pad[58];
} __attribute__ ((packed));
struct freecom_ide_out {
u8 Type; /* Type + IDE register. */
u8 Pad;
__le16 Value; /* Value to write. */
u8 Pad2[60];
};
struct freecom_ide_in {
u8 Type; /* Type | IDE register. */
u8 Pad[63];
};
struct freecom_status {
u8 Status;
u8 Reason;
__le16 Count;
u8 Pad[60];
};
/*
* Freecom stuffs the interrupt status in the INDEX_STAT bit of the ide
* register.
*/
#define FCM_INT_STATUS 0x02 /* INDEX_STAT */
#define FCM_STATUS_BUSY 0x80
/*
* These are the packet types. The low bit indicates that this command
* should wait for an interrupt.
*/
#define FCM_PACKET_ATAPI 0x21
#define FCM_PACKET_STATUS 0x20
/*
* Receive data from the IDE interface. The ATAPI packet has already
* waited, so the data should be immediately available.
*/
#define FCM_PACKET_INPUT 0x81
/* Send data to the IDE interface. */
#define FCM_PACKET_OUTPUT 0x01
/*
* Write a value to an ide register. Or the ide register to write after
* munging the address a bit.
*/
#define FCM_PACKET_IDE_WRITE 0x40
#define FCM_PACKET_IDE_READ 0xC0
/* All packets (except for status) are 64 bytes long. */
#define FCM_PACKET_LENGTH 64
#define FCM_STATUS_PACKET_LENGTH 4
static int init_freecom(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) }
static struct usb_device_id freecom_usb_ids[] = {
# include "unusual_freecom.h"
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, freecom_usb_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 freecom_unusual_dev_list[] = {
# include "unusual_freecom.h"
{ } /* Terminating entry */
};
#undef UNUSUAL_DEV
static int
freecom_readdata (struct scsi_cmnd *srb, struct us_data *us,
unsigned int ipipe, unsigned int opipe, int count)
{
struct freecom_xfer_wrap *fxfr =
(struct freecom_xfer_wrap *) us->iobuf;
int result;
fxfr->Type = FCM_PACKET_INPUT | 0x00;
fxfr->Timeout = 0; /* Short timeout for debugging. */
fxfr->Count = cpu_to_le32 (count);
memset (fxfr->Pad, 0, sizeof (fxfr->Pad));
usb_stor_dbg(us, "Read data Freecom! (c=%d)\n", count);
/* Issue the transfer command. */
result = usb_stor_bulk_transfer_buf (us, opipe, fxfr,
FCM_PACKET_LENGTH, NULL);
if (result != USB_STOR_XFER_GOOD) {
usb_stor_dbg(us, "Freecom readdata transport error\n");
return USB_STOR_TRANSPORT_ERROR;
}
/* Now transfer all of our blocks. */
usb_stor_dbg(us, "Start of read\n");
result = usb_stor_bulk_srb(us, ipipe, srb);
usb_stor_dbg(us, "freecom_readdata done!\n");
if (result > USB_STOR_XFER_SHORT)
return USB_STOR_TRANSPORT_ERROR;
return USB_STOR_TRANSPORT_GOOD;
}
static int
freecom_writedata (struct scsi_cmnd *srb, struct us_data *us,
int unsigned ipipe, unsigned int opipe, int count)
{
struct freecom_xfer_wrap *fxfr =
(struct freecom_xfer_wrap *) us->iobuf;
int result;
fxfr->Type = FCM_PACKET_OUTPUT | 0x00;
fxfr->Timeout = 0; /* Short timeout for debugging. */
fxfr->Count = cpu_to_le32 (count);
memset (fxfr->Pad, 0, sizeof (fxfr->Pad));
usb_stor_dbg(us, "Write data Freecom! (c=%d)\n", count);
/* Issue the transfer command. */
result = usb_stor_bulk_transfer_buf (us, opipe, fxfr,
FCM_PACKET_LENGTH, NULL);
if (result != USB_STOR_XFER_GOOD) {
usb_stor_dbg(us, "Freecom writedata transport error\n");
return USB_STOR_TRANSPORT_ERROR;
}
/* Now transfer all of our blocks. */
usb_stor_dbg(us, "Start of write\n");
result = usb_stor_bulk_srb(us, opipe, srb);
usb_stor_dbg(us, "freecom_writedata done!\n");
if (result > USB_STOR_XFER_SHORT)
return USB_STOR_TRANSPORT_ERROR;
return USB_STOR_TRANSPORT_GOOD;
}
/*
* Transport for the Freecom USB/IDE adaptor.
*
*/
static int freecom_transport(struct scsi_cmnd *srb, struct us_data *us)
{
struct freecom_cb_wrap *fcb;
struct freecom_status *fst;
unsigned int ipipe, opipe; /* We need both pipes. */
int result;
unsigned int partial;
int length;
fcb = (struct freecom_cb_wrap *) us->iobuf;
fst = (struct freecom_status *) us->iobuf;
usb_stor_dbg(us, "Freecom TRANSPORT STARTED\n");
/* Get handles for both transports. */
opipe = us->send_bulk_pipe;
ipipe = us->recv_bulk_pipe;
/* The ATAPI Command always goes out first. */
fcb->Type = FCM_PACKET_ATAPI | 0x00;
fcb->Timeout = 0;
memcpy (fcb->Atapi, srb->cmnd, 12);
memset (fcb->Filler, 0, sizeof (fcb->Filler));
US_DEBUG(pdump(us, srb->cmnd, 12));
/* Send it out. */
result = usb_stor_bulk_transfer_buf (us, opipe, fcb,
FCM_PACKET_LENGTH, NULL);
/*
* The Freecom device will only fail if there is something wrong in
* USB land. It returns the status in its own registers, which
* come back in the bulk pipe.
*/
if (result != USB_STOR_XFER_GOOD) {
usb_stor_dbg(us, "freecom transport error\n");
return USB_STOR_TRANSPORT_ERROR;
}
/*
* There are times we can optimize out this status read, but it
* doesn't hurt us to always do it now.
*/
result = usb_stor_bulk_transfer_buf (us, ipipe, fst,
FCM_STATUS_PACKET_LENGTH, &partial);
usb_stor_dbg(us, "foo Status result %d %u\n", result, partial);
if (result != USB_STOR_XFER_GOOD)
return USB_STOR_TRANSPORT_ERROR;
US_DEBUG(pdump(us, (void *)fst, partial));
/*
* The firmware will time-out commands after 20 seconds. Some commands
* can legitimately take longer than this, so we use a different
* command that only waits for the interrupt and then sends status,
* without having to send a new ATAPI command to the device.
*
* NOTE: There is some indication that a data transfer after a timeout
* may not work, but that is a condition that should never happen.
*/
while (fst->Status & FCM_STATUS_BUSY) {
usb_stor_dbg(us, "20 second USB/ATAPI bridge TIMEOUT occurred!\n");
usb_stor_dbg(us, "fst->Status is %x\n", fst->Status);
/* Get the status again */
fcb->Type = FCM_PACKET_STATUS;
fcb->Timeout = 0;
memset (fcb->Atapi, 0, sizeof(fcb->Atapi));
memset (fcb->Filler, 0, sizeof (fcb->Filler));
/* Send it out. */
result = usb_stor_bulk_transfer_buf (us, opipe, fcb,
FCM_PACKET_LENGTH, NULL);
/*
* The Freecom device will only fail if there is something
* wrong in USB land. It returns the status in its own
* registers, which come back in the bulk pipe.
*/
if (result != USB_STOR_XFER_GOOD) {
usb_stor_dbg(us, "freecom transport error\n");
return USB_STOR_TRANSPORT_ERROR;
}
/* get the data */
result = usb_stor_bulk_transfer_buf (us, ipipe, fst,
FCM_STATUS_PACKET_LENGTH, &partial);
usb_stor_dbg(us, "bar Status result %d %u\n", result, partial);
if (result != USB_STOR_XFER_GOOD)
return USB_STOR_TRANSPORT_ERROR;
US_DEBUG(pdump(us, (void *)fst, partial));
}
if (partial != 4)
return USB_STOR_TRANSPORT_ERROR;
if ((fst->Status & 1) != 0) {
usb_stor_dbg(us, "operation failed\n");
return USB_STOR_TRANSPORT_FAILED;
}
/*
* The device might not have as much data available as we
* requested. If you ask for more than the device has, this reads
* and such will hang.
*/
usb_stor_dbg(us, "Device indicates that it has %d bytes available\n",
le16_to_cpu(fst->Count));
usb_stor_dbg(us, "SCSI requested %d\n", scsi_bufflen(srb));
/* Find the length we desire to read. */
switch (srb->cmnd[0]) {
case INQUIRY:
case REQUEST_SENSE: /* 16 or 18 bytes? spec says 18, lots of devices only have 16 */
case MODE_SENSE:
case MODE_SENSE_10:
length = le16_to_cpu(fst->Count);
break;
default:
length = scsi_bufflen(srb);
}
/* verify that this amount is legal */
if (length > scsi_bufflen(srb)) {
length = scsi_bufflen(srb);
usb_stor_dbg(us, "Truncating request to match buffer length: %d\n",
length);
}
/*
* What we do now depends on what direction the data is supposed to
* move in.
*/
switch (us->srb->sc_data_direction) {
case DMA_FROM_DEVICE:
/* catch bogus "read 0 length" case */
if (!length)
break;
/*
* Make sure that the status indicates that the device
* wants data as well.
*/
if ((fst->Status & DRQ_STAT) == 0 || (fst->Reason & 3) != 2) {
usb_stor_dbg(us, "SCSI wants data, drive doesn't have any\n");
return USB_STOR_TRANSPORT_FAILED;
}
result = freecom_readdata (srb, us, ipipe, opipe, length);
if (result != USB_STOR_TRANSPORT_GOOD)
return result;
usb_stor_dbg(us, "Waiting for status\n");
result = usb_stor_bulk_transfer_buf (us, ipipe, fst,
FCM_PACKET_LENGTH, &partial);
US_DEBUG(pdump(us, (void *)fst, partial));
if (partial != 4 || result > USB_STOR_XFER_SHORT)
return USB_STOR_TRANSPORT_ERROR;
if ((fst->Status & ERR_STAT) != 0) {
usb_stor_dbg(us, "operation failed\n");
return USB_STOR_TRANSPORT_FAILED;
}
if ((fst->Reason & 3) != 3) {
usb_stor_dbg(us, "Drive seems still hungry\n");
return USB_STOR_TRANSPORT_FAILED;
}
usb_stor_dbg(us, "Transfer happy\n");
break;
case DMA_TO_DEVICE:
/* catch bogus "write 0 length" case */
if (!length)
break;
/*
* Make sure the status indicates that the device wants to
* send us data.
*/
/* !!IMPLEMENT!! */
result = freecom_writedata (srb, us, ipipe, opipe, length);
if (result != USB_STOR_TRANSPORT_GOOD)
return result;
usb_stor_dbg(us, "Waiting for status\n");
result = usb_stor_bulk_transfer_buf (us, ipipe, fst,
FCM_PACKET_LENGTH, &partial);
if (partial != 4 || result > USB_STOR_XFER_SHORT)
return USB_STOR_TRANSPORT_ERROR;
if ((fst->Status & ERR_STAT) != 0) {
usb_stor_dbg(us, "operation failed\n");
return USB_STOR_TRANSPORT_FAILED;
}
if ((fst->Reason & 3) != 3) {
usb_stor_dbg(us, "Drive seems still hungry\n");
return USB_STOR_TRANSPORT_FAILED;
}
usb_stor_dbg(us, "Transfer happy\n");
break;
case DMA_NONE:
/* Easy, do nothing. */
break;
default:
/* should never hit here -- filtered in usb.c */
usb_stor_dbg(us, "freecom unimplemented direction: %d\n",
us->srb->sc_data_direction);
/* Return fail, SCSI seems to handle this better. */
return USB_STOR_TRANSPORT_FAILED;
break;
}
return USB_STOR_TRANSPORT_GOOD;
}
static int init_freecom(struct us_data *us)
{
int result;
char *buffer = us->iobuf;
/*
* The DMA-mapped I/O buffer is 64 bytes long, just right for
* all our packets. No need to allocate any extra buffer space.
*/
result = usb_stor_control_msg(us, us->recv_ctrl_pipe,
0x4c, 0xc0, 0x4346, 0x0, buffer, 0x20, 3*HZ);
buffer[32] = '\0';
usb_stor_dbg(us, "String returned from FC init is: %s\n", buffer);
/*
* Special thanks to the people at Freecom for providing me with
* this "magic sequence", which they use in their Windows and MacOS
* drivers to make sure that all the attached perhiperals are
* properly reset.
*/
/* send reset */
result = usb_stor_control_msg(us, us->send_ctrl_pipe,
0x4d, 0x40, 0x24d8, 0x0, NULL, 0x0, 3*HZ);
usb_stor_dbg(us, "result from activate reset is %d\n", result);
/* wait 250ms */
msleep(250);
/* clear reset */
result = usb_stor_control_msg(us, us->send_ctrl_pipe,
0x4d, 0x40, 0x24f8, 0x0, NULL, 0x0, 3*HZ);
usb_stor_dbg(us, "result from clear reset is %d\n", result);
/* wait 3 seconds */
msleep(3 * 1000);
return USB_STOR_TRANSPORT_GOOD;
}
static int usb_stor_freecom_reset(struct us_data *us)
{
printk (KERN_CRIT "freecom reset called\n");
/* We don't really have this feature. */
return FAILED;
}
#ifdef CONFIG_USB_STORAGE_DEBUG
static void pdump(struct us_data *us, void *ibuffer, int length)
{
static char line[80];
int offset = 0;
unsigned char *buffer = (unsigned char *) ibuffer;
int i, j;
int from, base;
offset = 0;
for (i = 0; i < length; i++) {
if ((i & 15) == 0) {
if (i > 0) {
offset += sprintf (line+offset, " - ");
for (j = i - 16; j < i; j++) {
if (buffer[j] >= 32 && buffer[j] <= 126)
line[offset++] = buffer[j];
else
line[offset++] = '.';
}
line[offset] = 0;
usb_stor_dbg(us, "%s\n", line);
offset = 0;
}
offset += sprintf (line+offset, "%08x:", i);
} else if ((i & 7) == 0) {
offset += sprintf (line+offset, " -");
}
offset += sprintf (line+offset, " %02x", buffer[i] & 0xff);
}
/* Add the last "chunk" of data. */
from = (length - 1) % 16;
base = ((length - 1) / 16) * 16;
for (i = from + 1; i < 16; i++)
offset += sprintf (line+offset, " ");
if (from < 8)
offset += sprintf (line+offset, " ");
offset += sprintf (line+offset, " - ");
for (i = 0; i <= from; i++) {
if (buffer[base+i] >= 32 && buffer[base+i] <= 126)
line[offset++] = buffer[base+i];
else
line[offset++] = '.';
}
line[offset] = 0;
usb_stor_dbg(us, "%s\n", line);
offset = 0;
}
#endif
static struct scsi_host_template freecom_host_template;
static int freecom_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
struct us_data *us;
int result;
result = usb_stor_probe1(&us, intf, id,
(id - freecom_usb_ids) + freecom_unusual_dev_list,
&freecom_host_template);
if (result)
return result;
us->transport_name = "Freecom";
us->transport = freecom_transport;
us->transport_reset = usb_stor_freecom_reset;
us->max_lun = 0;
result = usb_stor_probe2(us);
return result;
}
static struct usb_driver freecom_driver = {
.name = DRV_NAME,
.probe = freecom_probe,
.disconnect = usb_stor_disconnect,
.suspend = usb_stor_suspend,
.resume = usb_stor_resume,
.reset_resume = usb_stor_reset_resume,
.pre_reset = usb_stor_pre_reset,
.post_reset = usb_stor_post_reset,
.id_table = freecom_usb_ids,
.soft_unbind = 1,
.no_dynamic_id = 1,
};
module_usb_stor_driver(freecom_driver, freecom_host_template, DRV_NAME);
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