sisusb.c

linux-2.6.15.6

/*
 * sisusb - usb kernel driver for SiS315(E) based USB2VGA dongles
 *
 * Main part
 *
 * Copyright (C) 2005 by Thomas Winischhofer, Vienna, Austria
 *
 * If distributed as part of the Linux kernel, this code is licensed under the
 * terms of the GPL v2.
 *
 * Otherwise, the following license terms apply:
 *
 * * Redistribution and use in source and binary forms, with or without
 * * modification, are permitted provided that the following conditions
 * * are met:
 * * 1) Redistributions of source code must retain the above copyright
 * *    notice, this list of conditions and the following disclaimer.
 * * 2) Redistributions in binary form must reproduce the above copyright
 * *    notice, this list of conditions and the following disclaimer in the
 * *    documentation and/or other materials provided with the distribution.
 * * 3) The name of the author may not be used to endorse or promote products
 * *    derived from this software without specific psisusbr written permission.
 * *
 * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESSED OR
 * * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Author: 	Thomas Winischhofer <[e-mail]>
 *
 */

#include <linux/config.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/kref.h>
#include <linux/usb.h>
#include <linux/smp_lock.h>
#include <linux/vmalloc.h>

#include "sisusb.h"

#ifdef INCL_SISUSB_CON
#include <linux/font.h>
#endif

#define SISUSB_DONTSYNC

/* Forward declarations / clean-up routines */

#ifdef INCL_SISUSB_CON
int	sisusb_setreg(struct sisusb_usb_data *sisusb, int port, u8 data);
int	sisusb_getreg(struct sisusb_usb_data *sisusb, int port, u8 *data);
int	sisusb_setidxreg(struct sisusb_usb_data *sisusb, int port, u8 index, u8 data);
int	sisusb_getidxreg(struct sisusb_usb_data *sisusb, int port, u8 index, u8 *data);
int	sisusb_setidxregandor(struct sisusb_usb_data *sisusb, int port, u8 idx,	u8 myand, u8 myor);
int	sisusb_setidxregor(struct sisusb_usb_data *sisusb, int port, u8 index, u8 myor);
int	sisusb_setidxregand(struct sisusb_usb_data *sisusb, int port, u8 idx, u8 myand);

int	sisusb_writeb(struct sisusb_usb_data *sisusb, u32 adr, u8 data);
int	sisusb_readb(struct sisusb_usb_data *sisusb, u32 adr, u8 *data);
int	sisusb_writew(struct sisusb_usb_data *sisusb, u32 adr, u16 data);
int	sisusb_readw(struct sisusb_usb_data *sisusb, u32 adr, u16 *data);
int	sisusb_copy_memory(struct sisusb_usb_data *sisusb, char *src,
			u32 dest, int length, size_t *bytes_written);

int	sisusb_reset_text_mode(struct sisusb_usb_data *sisusb, int init);

extern int  SiSUSBSetMode(struct SiS_Private *SiS_Pr, unsigned short ModeNo);
extern int  SiSUSBSetVESAMode(struct SiS_Private *SiS_Pr, unsigned short VModeNo);

extern void sisusb_init_concode(void);
extern int  sisusb_console_init(struct sisusb_usb_data *sisusb, int first, int last);
extern void sisusb_console_exit(struct sisusb_usb_data *sisusb);

extern void sisusb_set_cursor(struct sisusb_usb_data *sisusb, unsigned int location);

extern int  sisusbcon_do_font_op(struct sisusb_usb_data *sisusb, int set, int slot,
		u8 *arg, int cmapsz, int ch512, int dorecalc,
		struct vc_data *c, int fh, int uplock);

static int sisusb_first_vc = 0;
static int sisusb_last_vc = 0;
module_param_named(first, sisusb_first_vc, int, 0);
module_param_named(last, sisusb_last_vc, int, 0);
MODULE_PARM_DESC(first, "Number of first console to take over (1 - MAX_NR_CONSOLES)");
MODULE_PARM_DESC(last, "Number of last console to take over (1 - MAX_NR_CONSOLES)");
#endif

static struct usb_driver sisusb_driver;

DECLARE_MUTEX(disconnect_sem);

static void
sisusb_free_buffers(struct sisusb_usb_data *sisusb)
{
	int i;

	for (i = 0; i < NUMOBUFS; i++) {
		if (sisusb->obuf[i]) {
			usb_buffer_free(sisusb->sisusb_dev, sisusb->obufsize,
				sisusb->obuf[i], sisusb->transfer_dma_out[i]);
			sisusb->obuf[i] = NULL;
		}
	}
	if (sisusb->ibuf) {
		usb_buffer_free(sisusb->sisusb_dev, sisusb->ibufsize,
			sisusb->ibuf, sisusb->transfer_dma_in);
		sisusb->ibuf = NULL;
	}
}

static void
sisusb_free_urbs(struct sisusb_usb_data *sisusb)
{
	int i;

	for (i = 0; i < NUMOBUFS; i++) {
		usb_free_urb(sisusb->sisurbout[i]);
		sisusb->sisurbout[i] = NULL;
	}
	usb_free_urb(sisusb->sisurbin);
	sisusb->sisurbin = NULL;
}

/* Level 0: USB transport layer */

/* 1. out-bulks */

/* out-urb management */

/* Return 1 if all free, 0 otherwise */
static int
sisusb_all_free(struct sisusb_usb_data *sisusb)
{
	int i;

	for (i = 0; i < sisusb->numobufs; i++) {

		if (sisusb->urbstatus[i] & SU_URB_BUSY)
			return 0;

	}

	return 1;
}

/* Kill all busy URBs */
static void
sisusb_kill_all_busy(struct sisusb_usb_data *sisusb)
{
	int i;

	if (sisusb_all_free(sisusb))
		return;

	for (i = 0; i < sisusb->numobufs; i++) {

		if (sisusb->urbstatus[i] & SU_URB_BUSY)
			usb_kill_urb(sisusb->sisurbout[i]);

	}
}

/* Return 1 if ok, 0 if error (not all complete within timeout) */
static int
sisusb_wait_all_out_complete(struct sisusb_usb_data *sisusb)
{
	int timeout = 5 * HZ, i = 1;

	wait_event_timeout(sisusb->wait_q,
				(i = sisusb_all_free(sisusb)),
				 timeout);

	return i;
}

static int
sisusb_outurb_available(struct sisusb_usb_data *sisusb)
{
	int i;

	for (i = 0; i < sisusb->numobufs; i++) {

		if ((sisusb->urbstatus[i] & (SU_URB_BUSY|SU_URB_ALLOC)) == 0)
			return i;

	}

	return -1;
}

static int
sisusb_get_free_outbuf(struct sisusb_usb_data *sisusb)
{
	int i, timeout = 5 * HZ;

	wait_event_timeout(sisusb->wait_q,
				((i = sisusb_outurb_available(sisusb)) >= 0),
				timeout);

	return i;
}

static int
sisusb_alloc_outbuf(struct sisusb_usb_data *sisusb)
{
	int i;

	i = sisusb_outurb_available(sisusb);

	if (i >= 0)
		sisusb->urbstatus[i] |= SU_URB_ALLOC;

	return i;
}

static void
sisusb_free_outbuf(struct sisusb_usb_data *sisusb, int index)
{
	if ((index >= 0) && (index < sisusb->numobufs))
		sisusb->urbstatus[index] &= ~SU_URB_ALLOC;
}

/* completion callback */

static void
sisusb_bulk_completeout(struct urb *urb, struct pt_regs *regs)
{
	struct sisusb_urb_context *context = urb->context;
	struct sisusb_usb_data *sisusb;

	if (!context)
		return;

	sisusb = context->sisusb;

	if (!sisusb || !sisusb->sisusb_dev || !sisusb->present)
		return;

#ifndef SISUSB_DONTSYNC
	if (context->actual_length)
		*(context->actual_length) += urb->actual_length;
#endif

	sisusb->urbstatus[context->urbindex] &= ~SU_URB_BUSY;
	wake_up(&sisusb->wait_q);
}

static int
sisusb_bulkout_msg(struct sisusb_usb_data *sisusb, int index, unsigned int pipe, void *data,
		int len, int *actual_length, int timeout, unsigned int tflags,
		dma_addr_t transfer_dma)
{
	struct urb *urb = sisusb->sisurbout[index];
	int retval, byteswritten = 0;

	/* Set up URB */
	urb->transfer_flags = 0;

	usb_fill_bulk_urb(urb, sisusb->sisusb_dev, pipe, data, len,
		sisusb_bulk_completeout, &sisusb->urbout_context[index]);

	urb->transfer_flags |= tflags;
	urb->actual_length = 0;

	if ((urb->transfer_dma = transfer_dma))
		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	/* Set up context */
	sisusb->urbout_context[index].actual_length = (timeout) ?
						NULL : actual_length;

	/* Declare this urb/buffer in use */
	sisusb->urbstatus[index] |= SU_URB_BUSY;

	/* Submit URB */
	retval = usb_submit_urb(urb, GFP_ATOMIC);

	/* If OK, and if timeout > 0, wait for completion */
	if ((retval == 0) && timeout) {
		wait_event_timeout(sisusb->wait_q,
				   (!(sisusb->urbstatus[index] & SU_URB_BUSY)),
				   timeout);
		if (sisusb->urbstatus[index] & SU_URB_BUSY) {
			/* URB timed out... kill it and report error */
			usb_kill_urb(urb);
			retval = -ETIMEDOUT;
		} else {
			/* Otherwise, report urb status */
			retval = urb->status;
			byteswritten = urb->actual_length;
		}
	}

	if (actual_length)
		*actual_length = byteswritten;

	return retval;
}

/* 2. in-bulks */

/* completion callback */

static void
sisusb_bulk_completein(struct urb *urb, struct pt_regs *regs)
{
	struct sisusb_usb_data *sisusb = urb->context;

	if (!sisusb || !sisusb->sisusb_dev || !sisusb->present)
		return;

	sisusb->completein = 1;
	wake_up(&sisusb->wait_q);
}

static int
sisusb_bulkin_msg(struct sisusb_usb_data *sisusb, unsigned int pipe, void *data, int len,
		int *actual_length, int timeout, unsigned int tflags, dma_addr_t transfer_dma)
{
	struct urb *urb = sisusb->sisurbin;
	int retval, readbytes = 0;

	urb->transfer_flags = 0;

	usb_fill_bulk_urb(urb, sisusb->sisusb_dev, pipe, data, len,
			sisusb_bulk_completein, sisusb);

	urb->transfer_flags |= tflags;
	urb->actual_length = 0;

	if ((urb->transfer_dma = transfer_dma))
		urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	sisusb->completein = 0;
	retval = usb_submit_urb(urb, GFP_ATOMIC);
	if (retval == 0) {
		wait_event_timeout(sisusb->wait_q, sisusb->completein, timeout);
		if (!sisusb->completein) {
			/* URB timed out... kill it and report error */
			usb_kill_urb(urb);
			retval = -ETIMEDOUT;
		} else {
			/* URB completed within timout */
			retval = urb->status;
			readbytes = urb->actual_length;
		}
	}

	if (actual_length)
		*actual_length = readbytes;

	return retval;
}


/* Level 1:  */

/* Send a bulk message of variable size
 *
 * To copy the data from userspace, give pointer to "userbuffer",
 * to copy from (non-DMA) kernel memory, give "kernbuffer". If
 * both of these are NULL, it is assumed, that the transfer
 * buffer "sisusb->obuf[index]" is set up with the data to send.
 * Index is ignored if either kernbuffer or userbuffer is set.
 * If async is nonzero, URBs will be sent without waiting for
 * completion of the previous URB.
 *
 * (return 0 on success)
 */

static int sisusb_send_bulk_msg(struct sisusb_usb_data *sisusb, int ep, int len,
		char *kernbuffer, const char __user *userbuffer, int index,
		ssize_t *bytes_written, unsigned int tflags, int async)
{
	int result = 0, retry, count = len;
	int passsize, thispass, transferred_len = 0;
	int fromuser = (userbuffer != NULL) ? 1 : 0;
	int fromkern = (kernbuffer != NULL) ? 1 : 0;
	unsigned int pipe;
	char *buffer;

	(*bytes_written) = 0;

	/* Sanity check */
	if (!sisusb || !sisusb->present || !sisusb->sisusb_dev)
		return -ENODEV;

	/* If we copy data from kernel or userspace, force the
	 * allocation of a buffer/urb. If we have the data in
	 * the transfer buffer[index] already, reuse the buffer/URB
	 * if the length is > buffer size. (So, transmitting
	 * large data amounts directly from the transfer buffer
	 * treats the buffer as a ring buffer. However, we need
	 * to sync in this case.)
	 */
	if (fromuser || fromkern)
		index = -1;
	else if (len > sisusb->obufsize)
		async = 0;

	pipe = usb_sndbulkpipe(sisusb->sisusb_dev, ep);

	do {
		passsize = thispass = (sisusb->obufsize < count) ?
						sisusb->obufsize : count;

		if (index < 0)
			index = sisusb_get_free_outbuf(sisusb);

		if (index < 0)
			return -EIO;

		buffer = sisusb->obuf[index];

		if (fromuser) {

			if (copy_from_user(buffer, userbuffer, passsize))
				return -EFAULT;

			userbuffer += passsize;

		} else if (fromkern) {

			memcpy(buffer, kernbuffer, passsize);
			kernbuffer += passsize;

		}

		retry = 5;
		while (thispass) {

			if (!sisusb->sisusb_dev)
				return -ENODEV;

			result = sisusb_bulkout_msg(sisusb,
						index,
						pipe,
						buffer,
						thispass,
						&transferred_len,
						async ? 0 : 5 * HZ,
						tflags,
						sisusb->transfer_dma_out[index]);

			if (result == -ETIMEDOUT) {

				/* Will not happen if async */
				if (!retry--)
					return -ETIME;

				continue;

			} else if ((result == 0) && !async && transferred_len) {

				thispass -= transferred_len;
				if (thispass) {
					if (sisusb->transfer_dma_out) {
						/* If DMA, copy remaining
						 * to beginning of buffer
						 */
						memcpy(buffer,
						       buffer + transferred_len,
						       thispass);
					} else {
						/* If not DMA, simply increase
						 * the pointer
						 */
						buffer += transferred_len;
					}
				}

			} else
				break;
		};

		if (result)
			return result;

		(*bytes_written) += passsize;
		count            -= passsize;

		/* Force new allocation in next iteration */
		if (fromuser || fromkern)
			index = -1;

	} while (count > 0);

	if (async) {
#ifdef SISUSB_DONTSYNC
		(*bytes_written) = len;
		/* Some URBs/buffers might be busy */
#else
		sisusb_wait_all_out_complete(sisusb);
		(*bytes_written) = transferred_len;
		/* All URBs and all buffers are available */
#endif
	}

	return ((*bytes_written) == len) ? 0 : -EIO;
}

/* Receive a bulk message of variable size
 *
 * To copy the data to userspace, give pointer to "userbuffer",
 * to copy to kernel memory, give "kernbuffer". One of them
 * MUST be set. (There is no technique for letting the caller
 * read directly from the ibuf.)
 *
 */

static int sisusb_recv_bulk_msg(struct sisusb_usb_data *sisusb, int ep, int len,
		void *kernbuffer, char __user *userbuffer, ssize_t *bytes_read,
		unsigned int tflags)
{
	int result = 0, retry, count = len;
	int bufsize, thispass, transferred_len;
	unsigned int pipe;
	char *buffer;

	(*bytes_read) = 0;