urbasbytestream.c

USb in User space, a kernel module that use usb layer

/*
 * urbAsByteStream.c
 *
 * Author : Lionetti Salvatore <[e-mail]>
 * License: GPL
 *
 * 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"urbAsByteStream.h"
#include<linux/usb.h>		/* To have usb_pipetype().*/
/*#include<linux/usb_ch9.h>	* To have USB_ENDPOINT_*().*/
#include"util.h"		/* To have PRINT, Snprintf.*/

void initUrbD(struct urbDataT* ud, struct urb* urb) {
	memset(ud,0,sizeof(*ud));
	ud->urb=urb;
}
#if 0
bEndpointAddress non ci entra con alcuno dei flags riportati.
	0x0f: contiene lo identificativo dello endpoint,
	0x80: contiene la direzione.

urb->pipe
#define PIPE_ISOCHRONOUS		0
#define PIPE_INTERRUPT			1
#define PIPE_CONTROL			2
#define PIPE_BULK			3

bmAttributes (non ha la direzione)
#define USB_ENDPOINT_XFER_CONTROL	0
#define USB_ENDPOINT_XFER_ISOC		1
#define USB_ENDPOINT_XFER_BULK		2
#define USB_ENDPOINT_XFER_INT		3
#endif
int pipe2addr(int pipe) {
	int p2a[] = {
		USB_ENDPOINT_XFER_ISOC,
		USB_ENDPOINT_XFER_INT,
		USB_ENDPOINT_XFER_CONTROL,
		USB_ENDPOINT_XFER_BULK,
	};
	int addr = pipe & USB_DIR_IN;
	addr |= p2a[(usb_pipetype(pipe)) & 3];
	return addr;
}
/* Present in usersU.c.*/
int USBDo_dumpUrb(struct urb *urb,char* buf,int len);
char* usb_getTypeStr(int addr);
char* usb_getDirStr(int addr);

/* 
 * ISOC transfer: when submit() in kernel 2.6.15, usb subsystem set
 *  isoc[l]->status = -EXDEV
 *  isoc[l]->act_len= 0
 * so to see if urb is in progress, one can rely on this behavior.
 *
 * To give a uniform mean to 'urb running' choice (urb->status = -EINPROGRESS), put for all urb.
 */

/* Read until ret <=0 .*/
int readUrbD(struct urbDataT* ud, char* buf, int len) {
	int ritorno=ud?ud->urb?ud->urb->status:-EINVAL:-EINVAL;
	
	if (ritorno==0) {
		int addr=pipe2addr(ud->urb->pipe);
		int curr=ud->curr;

		if (!ritorno) {
			if ((addr & USB_ENDPOINT_XFERTYPE_MASK)==USB_ENDPOINT_XFER_ISOC) {
				while (!ritorno && ud->cur_frame<ud->urb->number_of_packets) {
					struct usb_iso_packet_descriptor *curr_iso;
					curr_iso=&(ud->urb->iso_frame_desc[ud->cur_frame]);

					curr=curr_iso->offset + ud->curr;
					ritorno=curr_iso->status?0:curr_iso->actual_length - ud->curr;
					if (ritorno>len)
						ritorno=len;
					ud->curr+=ritorno;
					if (curr_iso->actual_length==ud->curr || curr_iso->status) {
						ud->cur_frame++;
						ud->curr=0;
					}
				}
			} else {
				ritorno=ud->urb->actual_length - ud->curr;
				if (ritorno>len)
					ritorno=len;
				ud->curr+=ritorno;
			}
		}
		if (ritorno>0)
			if (CopyToUser(buf,ud->urb->transfer_buffer+curr,ritorno))
				ritorno = -EFAULT;
	}
	
	return ritorno;
	
}

/* write() until ret<=0. =0 mean EndOfUrb.*/
int writeUrbD(struct urbDataT* ud, char* buf, int len) {
	int ritorno=ud?ud->urb?ud->urb->status:-EFAULT:-EFAULT;
	if (ritorno==0) {
		if (ud->curr<0 || ud->curw<0 || ud->cur_frame<0)
			ritorno = -EFAULT;

		if (ritorno==0) {
			int curw=ud->curw;
			int addr=pipe2addr(ud->urb->pipe);
			if ((addr & USB_ENDPOINT_XFERTYPE_MASK)==USB_ENDPOINT_XFER_ISOC) {
				while (!ritorno && ud->cur_frame<ud->urb->number_of_packets) {
					struct usb_iso_packet_descriptor *curw_iso;
					curw_iso=&(ud->urb->iso_frame_desc[ud->cur_frame]);

					curw=curw_iso->offset + ud->curw;
					ritorno=curw_iso->length - ud->curw;
					if (ritorno>len)
						ritorno=len;
					ud->curw+=ritorno;
					if (curw_iso->length==ud->curw) {
						ud->cur_frame++;
						ud->curw=0;
					}
				}
			} else {
				ritorno=ud->urb->transfer_buffer_length - ud->curw;
				if (ritorno>len)
					ritorno=len;
				ud->curw+=ritorno;
			}
			if (ritorno>0)
				if (CopyFromUser(ud->urb->transfer_buffer+curw,buf,ritorno))
					ritorno = -EFAULT;
		}
	}
	return ritorno;
}
int emptyUrbD(struct urbDataT* ud) {
	return 0;
}
void resetUrbD(struct urbDataT* ud) {
	ud->curw = ud->curr = ud->cur_frame = 0;
}

int dumpUrbD(struct urbDataT* ud, char* buf, int len) {
	int l=0;
	if (ud) {
		Snprintf("\nurbDataT(urb,curr,curw,cur_frame)=");
		Snprintf("(0x%p,%d,%d,%d)",ud->urb, ud->curr, ud->curw, ud->cur_frame);
		if (ud->urb) {
			int addr=pipe2addr(ud->urb->pipe);
			int n;

			Snprintf("urb(%s/%s)",usb_getTypeStr(addr),usb_getDirStr(addr));
			l+=USBDo_dumpUrb(ud->urb, buf+l, len-l);
			if ((addr & USB_ENDPOINT_XFERTYPE_MASK)==USB_ENDPOINT_XFER_ISOC) {
				int f;
				for (f=0; f<ud->urb->number_of_packets; f++) {
					struct usb_iso_packet_descriptor *cur_iso;
					cur_iso=&(ud->urb->iso_frame_desc[f]);
					Snprintf("\nframe %d len(%d/%d) status(%d):",f+1,cur_iso->length,cur_iso->actual_length,cur_iso->status);
					for (n=cur_iso->offset; n<cur_iso->actual_length+cur_iso->offset; n++)
						Snprintf("%02x",(unsigned char)(((char*)ud->urb->transfer_buffer)[n]));
				}
			} else {
				Snprintf("\nlen(%d/%d)",ud->urb->actual_length,ud->urb->transfer_buffer_length);
				for (n=ud->curr; n<ud->urb->transfer_buffer_length; n++)
					Snprintf("%02x",(unsigned char)((char*)ud->urb->transfer_buffer)[n]);
			}
		}
	}
	return l;
}

void testUrbD(void) {
	char des[800];
	char data[100];
	int desL=800;
	int dataL=100;
	struct urb* urb;
	int l,k;

	for (l=0; l<dataL; l++)
		data[l]=l;

	urb=usb_alloc_urb(0,GFP_KERNEL);
	urb->transfer_buffer = data;
	urb->transfer_buffer_length = 10;
	urb->actual_length = 9;
	urb->pipe = (PIPE_BULK<<30)|(2<<15)|USB_DIR_IN/*usb_rcvbulkpipe(usu_device.dev,2)*/;

	{
		struct urbDataT ud;
		char data2[10];
		initUrbD(&ud, urb);
		dumpUrbD(&ud,des,desL);	PRINT("%s\n",des);
/*		dumpUrbD(&ud,des,desL);	PRINT("%s\n",des);*/
/*		PRINT("%s\n",des);*/
		l=readUrbD(&ud,data2,10);
		PRINT("\nREAD(10)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");
		
		l=readUrbD(&ud,data2,10);
		PRINT("\nREAD(10)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");

		l=writeUrbD(&ud,0,0);
		PRINT("\nWRITE(0)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");
		resetUrbD(&ud);
	}
	if (urb) usb_free_urb(urb);
	
	/* 100 bytes total: 10 packet, each frame have 10 bytes.
	 * We feel 1 bytes per packet, so 10 bytes.*/
	{
		int nPack=10;
		int bFram=10;
	
		urb=usb_alloc_urb(nPack,GFP_KERNEL);
		urb->transfer_buffer = data;
		urb->transfer_buffer_length = dataL;
		urb->actual_length = 0;
		urb->number_of_packets = nPack;
	/*	return (dev->devnum << 8) | (endpoint << 15);*/
		urb->pipe = (PIPE_ISOCHRONOUS<<30)|(0x83<<15)|USB_DIR_IN/*usb_rcvbulkpipe(usu_device.dev,2)*/;
		for (l=0; l<urb->number_of_packets; l++) {
			urb->iso_frame_desc[l].offset=l*bFram;
			urb->iso_frame_desc[l].length=bFram;
			urb->iso_frame_desc[l].actual_length=1;
			urb->iso_frame_desc[l].status=0;
		}
		urb->iso_frame_desc[1].actual_length=3;
		urb->iso_frame_desc[2].status=-EINVAL;
	}
	{
		struct urbDataT ud;
		char data2[10];
		initUrbD(&ud, urb);
		dumpUrbD(&ud,des,desL);	PRINT("%s\n",des);
		l=readUrbD(&ud,data2,10);
		PRINT("\nREAD(10)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");
		
		l=readUrbD(&ud,data2,10);
		PRINT("\nREAD(10)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");

		l=readUrbD(&ud,data2,10);
		PRINT("\nREAD(10)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");

		l=readUrbD(&ud,data2,10);
		PRINT("\nREAD(10)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");

		writeUrbD(&ud,0,0);
		PRINT("\nWRITE(0)=%d (",l); for (k=0; k<l; k++) PRINT("%02x",data2[k]); PRINT(")");
		resetUrbD(&ud);
	}
	if (urb) usb_free_urb(urb);
}