2 em2820-core.c - driver for Empia EM2800/EM2820/2840 USB video capture devices
4 Copyright (C) 2005 Markus Rechberger <mrechberger@gmail.com>
5 Ludovico Cavedon <cavedon@sssup.it>
6 Mauro Carvalho Chehab <mchehab@brturbo.com.br>
8 Based on the em2800 driver from Sascha Sommer <saschasommer@freenet.de>
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25 #include <linux/init.h>
26 #include <linux/list.h>
27 #include <linux/module.h>
28 #include <linux/moduleparam.h>
29 #include <linux/usb.h>
30 #include <linux/vmalloc.h>
34 /* #define ENABLE_DEBUG_ISOC_FRAMES */
36 unsigned int core_debug;
37 module_param(core_debug,int,0644);
38 MODULE_PARM_DESC(core_debug,"enable debug messages [core]");
40 #define em2820_coredbg(fmt, arg...) do {\
42 printk(KERN_INFO "%s %s :"fmt, \
43 dev->name, __FUNCTION__ , ##arg); } while (0)
45 unsigned int reg_debug;
46 module_param(reg_debug,int,0644);
47 MODULE_PARM_DESC(reg_debug,"enable debug messages [URB reg]");
49 #define em2820_regdbg(fmt, arg...) do {\
51 printk(KERN_INFO "%s %s :"fmt, \
52 dev->name, __FUNCTION__ , ##arg); } while (0)
54 unsigned int isoc_debug;
55 module_param(isoc_debug,int,0644);
56 MODULE_PARM_DESC(isoc_debug,"enable debug messages [isoc transfers]");
58 #define em2820_isocdbg(fmt, arg...) do {\
60 printk(KERN_INFO "%s %s :"fmt, \
61 dev->name, __FUNCTION__ , ##arg); } while (0)
63 static int alt = EM2820_PINOUT;
64 module_param(alt, int, 0644);
65 MODULE_PARM_DESC(alt, "alternate setting to use for video endpoint");
67 /* ------------------------------------------------------------------ */
68 /* debug help functions */
70 static const char *v4l1_ioctls[] = {
71 "0", "CGAP", "GCHAN", "SCHAN", "GTUNER", "STUNER", "GPICT", "SPICT",
72 "CCAPTURE", "GWIN", "SWIN", "GFBUF", "SFBUF", "KEY", "GFREQ",
73 "SFREQ", "GAUDIO", "SAUDIO", "SYNC", "MCAPTURE", "GMBUF", "GUNIT",
74 "GCAPTURE", "SCAPTURE", "SPLAYMODE", "SWRITEMODE", "GPLAYINFO",
75 "SMICROCODE", "GVBIFMT", "SVBIFMT" };
76 #define V4L1_IOCTLS ARRAY_SIZE(v4l1_ioctls)
78 static const char *v4l2_ioctls[] = {
79 "QUERYCAP", "1", "ENUM_PIXFMT", "ENUM_FBUFFMT", "G_FMT", "S_FMT",
80 "G_COMP", "S_COMP", "REQBUFS", "QUERYBUF", "G_FBUF", "S_FBUF",
81 "G_WIN", "S_WIN", "PREVIEW", "QBUF", "16", "DQBUF", "STREAMON",
82 "STREAMOFF", "G_PERF", "G_PARM", "S_PARM", "G_STD", "S_STD",
83 "ENUMSTD", "ENUMINPUT", "G_CTRL", "S_CTRL", "G_TUNER", "S_TUNER",
84 "G_FREQ", "S_FREQ", "G_AUDIO", "S_AUDIO", "35", "QUERYCTRL",
85 "QUERYMENU", "G_INPUT", "S_INPUT", "ENUMCVT", "41", "42", "43",
86 "44", "45", "G_OUTPUT", "S_OUTPUT", "ENUMOUTPUT", "G_AUDOUT",
87 "S_AUDOUT", "ENUMFX", "G_EFFECT", "S_EFFECT", "G_MODULATOR",
90 #define V4L2_IOCTLS ARRAY_SIZE(v4l2_ioctls)
92 void em2820_print_ioctl(char *name, unsigned int cmd)
96 switch (_IOC_DIR(cmd)) {
97 case _IOC_NONE: dir = "--"; break;
98 case _IOC_READ: dir = "r-"; break;
99 case _IOC_WRITE: dir = "-w"; break;
100 case _IOC_READ | _IOC_WRITE: dir = "rw"; break;
101 default: dir = "??"; break;
103 switch (_IOC_TYPE(cmd)) {
105 printk(KERN_DEBUG "%s: ioctl 0x%08x (v4l1, %s, VIDIOC%s)\n",
106 name, cmd, dir, (_IOC_NR(cmd) < V4L1_IOCTLS) ?
107 v4l1_ioctls[_IOC_NR(cmd)] : "???");
110 printk(KERN_DEBUG "%s: ioctl 0x%08x (v4l2, %s, VIDIOC_%s)\n",
111 name, cmd, dir, (_IOC_NR(cmd) < V4L2_IOCTLS) ?
112 v4l2_ioctls[_IOC_NR(cmd)] : "???");
115 printk(KERN_DEBUG "%s: ioctl 0x%08x (???, %s, #%d)\n",
116 name, cmd, dir, _IOC_NR(cmd));
120 static void *rvmalloc(size_t size)
125 size = PAGE_ALIGN(size);
127 mem = vmalloc_32((unsigned long)size);
131 memset(mem, 0, size);
133 adr = (unsigned long)mem;
135 SetPageReserved(vmalloc_to_page((void *)adr));
143 static void rvfree(void *mem, size_t size)
150 size = PAGE_ALIGN(size);
152 adr = (unsigned long)mem;
154 ClearPageReserved(vmalloc_to_page((void *)adr));
163 * em2820_request_buffers()
164 * allocate a number of buffers
166 u32 em2820_request_buffers(struct em2820 *dev, u32 count)
168 const size_t imagesize = PAGE_ALIGN(dev->frame_size); /*needs to be page aligned cause the buffers can be mapped individually! */
171 em2820_coredbg("requested %i buffers with size %i", count, imagesize);
172 if (count > EM2820_NUM_FRAMES)
173 count = EM2820_NUM_FRAMES;
175 dev->num_frames = count;
176 while (dev->num_frames > 0) {
177 if ((buff = rvmalloc(dev->num_frames * imagesize)))
182 for (i = 0; i < dev->num_frames; i++) {
183 dev->frame[i].bufmem = buff + i * imagesize;
184 dev->frame[i].buf.index = i;
185 dev->frame[i].buf.m.offset = i * imagesize;
186 dev->frame[i].buf.length = dev->frame_size;
187 dev->frame[i].buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
188 dev->frame[i].buf.sequence = 0;
189 dev->frame[i].buf.field = V4L2_FIELD_NONE;
190 dev->frame[i].buf.memory = V4L2_MEMORY_MMAP;
191 dev->frame[i].buf.flags = 0;
193 return dev->num_frames;
197 * em2820_queue_unusedframes()
198 * add all frames that are not currently in use to the inbuffer queue
200 void em2820_queue_unusedframes(struct em2820 *dev)
202 unsigned long lock_flags;
205 for (i = 0; i < dev->num_frames; i++)
206 if (dev->frame[i].state == F_UNUSED) {
207 dev->frame[i].state = F_QUEUED;
208 spin_lock_irqsave(&dev->queue_lock, lock_flags);
209 list_add_tail(&dev->frame[i].frame, &dev->inqueue);
210 spin_unlock_irqrestore(&dev->queue_lock, lock_flags);
215 * em2820_release_buffers()
218 void em2820_release_buffers(struct em2820 *dev)
220 if (dev->num_frames) {
221 rvfree(dev->frame[0].bufmem,
222 dev->num_frames * PAGE_ALIGN(dev->frame[0].buf.length));
228 * em2820_read_reg_req()
229 * reads data from the usb device specifying bRequest
231 int em2820_read_reg_req_len(struct em2820 *dev, u8 req, u16 reg,
236 em2820_regdbg("req=%02x, reg=%02x ", req, reg);
238 ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
239 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
240 0x0000, reg, buf, len, HZ);
243 printk(ret < 0 ? " failed!\n" : "%02x values: ", ret);
244 for (byte = 0; byte < len; byte++) {
245 printk(" %02x", buf[byte]);
254 * em2820_read_reg_req()
255 * reads data from the usb device specifying bRequest
257 int em2820_read_reg_req(struct em2820 *dev, u8 req, u16 reg)
262 em2820_regdbg("req=%02x, reg=%02x:", req, reg);
264 ret = usb_control_msg(dev->udev, usb_rcvctrlpipe(dev->udev, 0), req,
265 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
266 0x0000, reg, &val, 1, HZ);
269 printk(ret < 0 ? " failed!\n" : "%02x\n", val);
277 int em2820_read_reg(struct em2820 *dev, u16 reg)
279 return em2820_read_reg_req(dev, USB_REQ_GET_STATUS, reg);
283 * em2820_write_regs_req()
284 * sends data to the usb device, specifying bRequest
286 int em2820_write_regs_req(struct em2820 *dev, u8 req, u16 reg, char *buf,
291 /*usb_control_msg seems to expect a kmalloced buffer */
292 unsigned char *bufs = kmalloc(len, GFP_KERNEL);
294 em2820_regdbg("req=%02x reg=%02x:", req, reg);
298 for (i = 0; i < len; ++i)
299 printk (" %02x", (unsigned char)buf[i]);
305 memcpy(bufs, buf, len);
306 ret = usb_control_msg(dev->udev, usb_sndctrlpipe(dev->udev, 0), req,
307 USB_DIR_OUT | USB_TYPE_VENDOR | USB_RECIP_DEVICE,
308 0x0000, reg, bufs, len, HZ);
309 mdelay(5); /* FIXME: magic number */
314 int em2820_write_regs(struct em2820 *dev, u16 reg, char *buf, int len)
316 return em2820_write_regs_req(dev, USB_REQ_GET_STATUS, reg, buf, len);
320 * em2820_write_reg_bits()
321 * sets only some bits (specified by bitmask) of a register, by first reading
324 int em2820_write_reg_bits(struct em2820 *dev, u16 reg, u8 val,
329 if ((oldval = em2820_read_reg(dev, reg)) < 0)
331 newval = (((u8) oldval) & ~bitmask) | (val & bitmask);
332 return em2820_write_regs(dev, reg, &newval, 1);
336 * em2820_write_ac97()
337 * write a 16 bit value to the specified AC97 address (LSB first!)
339 int em2820_write_ac97(struct em2820 *dev, u8 reg, u8 * val)
342 u8 addr = reg & 0x7f;
343 if ((ret = em2820_write_regs(dev, AC97LSB_REG, val, 2)) < 0)
345 if ((ret = em2820_write_regs(dev, AC97ADDR_REG, &addr, 1)) < 0)
347 if ((ret = em2820_read_reg(dev, AC97BUSY_REG)) < 0)
349 else if (((u8) ret) & 0x01) {
350 em2820_warn ("AC97 command still being exectuted: not handled properly!\n");
355 int em2820_audio_analog_set(struct em2820 *dev)
357 char s[2] = { 0x00, 0x00 };
358 s[0] |= 0x1f - dev->volume;
359 s[1] |= 0x1f - dev->volume;
362 return em2820_write_ac97(dev, MASTER_AC97, s);
366 int em2820_colorlevels_set_default(struct em2820 *dev)
368 em2820_write_regs(dev, YGAIN_REG, "\x10", 1); /* contrast */
369 em2820_write_regs(dev, YOFFSET_REG, "\x00", 1); /* brightness */
370 em2820_write_regs(dev, UVGAIN_REG, "\x10", 1); /* saturation */
371 em2820_write_regs(dev, UOFFSET_REG, "\x00", 1);
372 em2820_write_regs(dev, VOFFSET_REG, "\x00", 1);
373 em2820_write_regs(dev, SHARPNESS_REG, "\x00", 1);
375 em2820_write_regs(dev, GAMMA_REG, "\x20", 1);
376 em2820_write_regs(dev, RGAIN_REG, "\x20", 1);
377 em2820_write_regs(dev, GGAIN_REG, "\x20", 1);
378 em2820_write_regs(dev, BGAIN_REG, "\x20", 1);
379 em2820_write_regs(dev, ROFFSET_REG, "\x00", 1);
380 em2820_write_regs(dev, GOFFSET_REG, "\x00", 1);
381 return em2820_write_regs(dev, BOFFSET_REG, "\x00", 1);
384 int em2820_capture_start(struct em2820 *dev, int start)
387 /* FIXME: which is the best order? */
388 /* video registers are sampled by VREF */
389 if ((ret = em2820_write_reg_bits(dev, USBSUSP_REG, start ? 0x10 : 0x00,
392 /* enable video capture */
393 return em2820_write_regs(dev, VINENABLE_REG, start ? "\x67" : "\x27", 1);
396 int em2820_outfmt_set_yuv422(struct em2820 *dev)
398 em2820_write_regs(dev, OUTFMT_REG, "\x34", 1);
399 em2820_write_regs(dev, VINMODE_REG, "\x10", 1);
400 return em2820_write_regs(dev, VINCTRL_REG, "\x11", 1);
403 int em2820_accumulator_set(struct em2820 *dev, u8 xmin, u8 xmax, u8 ymin,
406 em2820_coredbg("em2820 Scale: (%d,%d)-(%d,%d)\n", xmin, ymin, xmax, ymax);
408 em2820_write_regs(dev, XMIN_REG, &xmin, 1);
409 em2820_write_regs(dev, XMAX_REG, &xmax, 1);
410 em2820_write_regs(dev, YMIN_REG, &ymin, 1);
411 return em2820_write_regs(dev, YMAX_REG, &ymax, 1);
414 int em2820_capture_area_set(struct em2820 *dev, u8 hstart, u8 vstart,
415 u16 width, u16 height)
419 u8 overflow = (height >> 7 & 0x02) | (width >> 8 & 0x01);
421 em2820_coredbg("em2820 Area Set: (%d,%d)\n", (width | (overflow & 2) << 7),
422 (height | (overflow & 1) << 8));
424 em2820_write_regs(dev, HSTART_REG, &hstart, 1);
425 em2820_write_regs(dev, VSTART_REG, &vstart, 1);
426 em2820_write_regs(dev, CWIDTH_REG, &cwidth, 1);
427 em2820_write_regs(dev, CHEIGHT_REG, &cheight, 1);
428 return em2820_write_regs(dev, OFLOW_REG, &overflow, 1);
431 int em2820_scaler_set(struct em2820 *dev, u16 h, u16 v)
436 em2820_write_regs(dev, HSCALELOW_REG, (char *)buf, 2);
439 em2820_write_regs(dev, VSCALELOW_REG, (char *)buf, 2);
442 /* random ratio scaling and 720x567 doesn't seem to work */
443 /* the maximum we can get is 640x480 with disabled scaler */
444 /* and norm_maxw set to 640 */
445 if(dev->width == 640 && dev->height == 480)
446 return em2820_write_regs(dev, COMPR_REG,"\x00",1);
447 if(dev->height > 288)
448 return em2820_write_regs(dev, COMPR_REG,"\x10",1);
450 return em2820_write_regs(dev, COMPR_REG,"\x20",1);
452 /* when H and V mixershould be used? */
453 /* return em2820_write_reg_bits(dev, COMPR_REG, (h ? 0x20 : 0x00) | (v ? 0x10 : 0x00), 0x30); */
454 /* it seems that both H and V scalers must be active to work correctly */
455 return em2820_write_reg_bits(dev, COMPR_REG, h
456 || v ? 0x30 : 0x00, 0x30);
459 /* FIXME: this only function read values from dev */
460 int em2820_resolution_set(struct em2820 *dev)
463 width = norm_maxw(dev);
464 height = norm_maxh(dev) >> 1;
466 em2820_outfmt_set_yuv422(dev);
467 em2820_accumulator_set(dev, 1, (width - 4) >> 2, 1, (height - 4) >> 2);
468 em2820_capture_area_set(dev, 0, 0, width >> 2, height >> 2);
469 return em2820_scaler_set(dev, dev->hscale, dev->vscale);
473 /******************* isoc transfer handling ****************************/
475 #ifdef ENABLE_DEBUG_ISOC_FRAMES
476 static void em2820_isoc_dump(struct urb *urb, struct pt_regs *regs)
482 printk(KERN_DEBUG "isocIrq: sf=%d np=%d ec=%x\n",
483 urb->start_frame, urb->number_of_packets,
485 for (i = 0; i < urb->number_of_packets; i++) {
487 urb->transfer_buffer +
488 urb->iso_frame_desc[i].offset;
489 int alen = urb->iso_frame_desc[i].actual_length;
491 if (buf[0] == 0x88) {
494 } else if (buf[0] == 0x22) {
496 "= l=%d nt=%d bpp=%d\n",
497 len - 4 * ntrans, ntrans,
498 ntrans == 0 ? 0 : len / ntrans);
502 printk(KERN_DEBUG "!\n");
504 printk(KERN_DEBUG " n=%d s=%d al=%d %x\n", i,
505 urb->iso_frame_desc[i].status,
506 urb->iso_frame_desc[i].actual_length,
508 *((unsigned char *)(urb->transfer_buffer +
509 urb->iso_frame_desc[i].
515 static inline int em2820_isoc_video(struct em2820 *dev,struct em2820_frame_t **f,
516 unsigned long *lock_flags, unsigned char buf)
519 if ((*f)->state == F_GRABBING) {
520 /*previous frame is incomplete */
521 if ((*f)->fieldbytesused < dev->field_size) {
522 (*f)->state = F_ERROR;
523 em2820_isocdbg ("dropping incomplete bottom field (%i missing bytes)",
524 dev->field_size-(*f)->fieldbytesused);
526 (*f)->state = F_DONE;
527 (*f)->buf.bytesused = dev->frame_size;
530 if ((*f)->state == F_DONE || (*f)->state == F_ERROR) {
531 /* move current frame to outqueue and get next free buffer from inqueue */
532 spin_lock_irqsave(&dev-> queue_lock, *lock_flags);
533 list_move_tail(&(*f)->frame, &dev->outqueue);
534 if (!list_empty(&dev->inqueue))
535 (*f) = list_entry(dev-> inqueue.next,
536 struct em2820_frame_t,frame);
539 spin_unlock_irqrestore(&dev->queue_lock,*lock_flags);
542 em2820_isocdbg ("new frame but no buffer is free");
545 do_gettimeofday(&(*f)->buf.timestamp);
546 (*f)->buf.sequence = ++dev->frame_count;
547 (*f)->buf.field = V4L2_FIELD_INTERLACED;
548 (*f)->state = F_GRABBING;
549 (*f)->buf.bytesused = 0;
551 (*f)->fieldbytesused = 0;
553 /* acquiring bottom field */
554 if ((*f)->state == F_GRABBING) {
555 if (!(*f)->top_field) {
556 (*f)->state = F_ERROR;
557 em2820_isocdbg ("unexpected begin of bottom field; discarding it");
558 } else if ((*f)-> fieldbytesused < dev->field_size - 172) {
559 (*f)->state = F_ERROR;
560 em2820_isocdbg ("dropping incomplete top field (%i missing bytes)",
561 dev->field_size-(*f)->fieldbytesused);
564 (*f)->fieldbytesused = 0;
571 static inline void em2820_isoc_video_copy(struct em2820 *dev,
572 struct em2820_frame_t **f, unsigned char *buf, int len)
574 void *fieldstart, *startwrite, *startread;
575 int linesdone, currlinedone, offset, lencopy,remain;
577 if(dev->frame_size != (*f)->buf.length){
578 em2820_err("frame_size %i and buf.length %i are different!!!\n",dev->frame_size,(*f)->buf.length);
582 if ((*f)->fieldbytesused + len > dev->field_size)
583 len =dev->field_size - (*f)->fieldbytesused;
587 fieldstart = (*f)->bufmem;
589 fieldstart = (*f)->bufmem + dev->bytesperline;
591 linesdone = (*f)->fieldbytesused / dev->bytesperline;
592 currlinedone = (*f)->fieldbytesused % dev->bytesperline;
593 offset = linesdone * dev->bytesperline * 2 + currlinedone;
594 startwrite = fieldstart + offset;
595 lencopy = dev->bytesperline - currlinedone;
596 lencopy = lencopy > remain ? remain : lencopy;
598 memcpy(startwrite, startread, lencopy);
602 startwrite += lencopy + dev->bytesperline;
603 startread += lencopy;
604 if (dev->bytesperline > remain)
607 lencopy = dev->bytesperline;
609 memcpy(startwrite, startread, lencopy);
613 (*f)->fieldbytesused += len;
618 * handles the incoming isoc urbs and fills the frames from our inqueue
620 void em2820_isocIrq(struct urb *urb, struct pt_regs *regs)
622 struct em2820 *dev = urb->context;
624 struct em2820_frame_t **f;
625 unsigned long lock_flags;
629 #ifdef ENABLE_DEBUG_ISOC_FRAMES
631 em2820_isoc_dump(urb, regs);
634 if (urb->status == -ENOENT)
637 f = &dev->frame_current;
639 if (dev->stream == STREAM_INTERRUPT) {
640 dev->stream = STREAM_OFF;
642 (*f)->state = F_QUEUED;
643 em2820_isocdbg("stream interrupted");
644 wake_up_interruptible(&dev->wait_stream);
647 if ((dev->state & DEV_DISCONNECTED) || (dev->state & DEV_MISCONFIGURED))
650 if (dev->stream == STREAM_ON && !list_empty(&dev->inqueue)) {
652 (*f) = list_entry(dev->inqueue.next,
653 struct em2820_frame_t, frame);
655 for (i = 0; i < urb->number_of_packets; i++) {
656 unsigned char *buf = urb->transfer_buffer +
657 urb->iso_frame_desc[i].offset;
658 int len = urb->iso_frame_desc[i].actual_length - 4;
660 if (urb->iso_frame_desc[i].status) {
661 em2820_isocdbg("data error: [%d] len=%d, status=%d", i,
662 urb->iso_frame_desc[i].actual_length,
663 urb->iso_frame_desc[i].status);
666 if (urb->iso_frame_desc[i].actual_length <= 0) {
667 em2820_isocdbg("packet %d is empty",i);
670 if (urb->iso_frame_desc[i].actual_length >
672 em2820_isocdbg("packet bigger than packet size");
676 if (buf[0] == 0x22 && buf[1] == 0x5a) {
677 em2820_isocdbg("Video frame, length=%i!",len);
679 if (em2820_isoc_video(dev,f,&lock_flags,buf[2]))
681 } else if (buf[0]==0x33 && buf[1]==0x95 && buf[2]==0x00) {
682 em2820_isocdbg("VBI HEADER!!!");
686 if ((*f)->state == F_GRABBING) {
687 em2820_isoc_video_copy(dev,f,buf, len);
692 for (i = 0; i < urb->number_of_packets; i++) {
693 urb->iso_frame_desc[i].status = 0;
694 urb->iso_frame_desc[i].actual_length = 0;
698 if ((status = usb_submit_urb(urb, GFP_ATOMIC))) {
699 em2820_errdev("resubmit of urb failed (error=%i)\n", status);
700 dev->state |= DEV_MISCONFIGURED;
702 wake_up_interruptible(&dev->wait_frame);
707 * em2820_uninit_isoc()
708 * deallocates the buffers and urbs allocated during em2820_init_iosc()
710 void em2820_uninit_isoc(struct em2820 *dev)
714 for (i = 0; i < EM2820_NUM_BUFS; i++) {
716 usb_kill_urb(dev->urb[i]);
717 if (dev->transfer_buffer[i]){
718 usb_buffer_free(dev->udev,(EM2820_NUM_PACKETS*dev->max_pkt_size),dev->transfer_buffer[i],dev->urb[i]->transfer_dma);
720 usb_free_urb(dev->urb[i]);
723 dev->transfer_buffer[i] = NULL;
725 em2820_capture_start(dev, 0);
730 * allocates transfer buffers and submits the urbs for isoc transfer
732 int em2820_init_isoc(struct em2820 *dev)
734 /* change interface to 3 which allowes the biggest packet sizes */
736 const int sb_size = EM2820_NUM_PACKETS * dev->max_pkt_size;
738 /* reset streaming vars */
739 dev->frame_current = NULL;
740 dev->frame_count = 0;
743 for (i = 0; i < EM2820_NUM_BUFS; i++) {
746 /* allocate transfer buffer */
747 urb = usb_alloc_urb(EM2820_NUM_PACKETS, GFP_KERNEL);
749 em2820_errdev("cannot alloc urb %i\n", i);
750 em2820_uninit_isoc(dev);
753 dev->transfer_buffer[i] = usb_buffer_alloc(dev->udev, sb_size, GFP_KERNEL,&urb->transfer_dma);
754 if (!dev->transfer_buffer[i]) {
756 ("unable to allocate %i bytes for transfer buffer %i\n",
758 em2820_uninit_isoc(dev);
761 memset(dev->transfer_buffer[i], 0, sb_size);
762 urb->dev = dev->udev;
764 urb->pipe = usb_rcvisocpipe(dev->udev, 0x82);
765 urb->transfer_flags = URB_ISO_ASAP;
767 urb->transfer_buffer = dev->transfer_buffer[i];
768 urb->complete = em2820_isocIrq;
769 urb->number_of_packets = EM2820_NUM_PACKETS;
770 urb->transfer_buffer_length = sb_size;
771 for (j = k = 0; j < EM2820_NUM_PACKETS;
772 j++, k += dev->max_pkt_size) {
773 urb->iso_frame_desc[j].offset = k;
774 urb->iso_frame_desc[j].length =
781 for (i = 0; i < EM2820_NUM_BUFS; i++) {
782 errCode = usb_submit_urb(dev->urb[i], GFP_KERNEL);
784 em2820_errdev("submit of urb %i failed (error=%i)\n", i,
786 em2820_uninit_isoc(dev);
794 int em2820_set_alternate(struct em2820 *dev)
796 int errCode, prev_alt = dev->alt;
800 if(dev->is_em2800){ /* always use the max packet size for em2800 based devices */
801 for(i=0;i< EM2820_MAX_ALT; i++)
802 if(dev->alt_max_pkt_size[i]>dev->alt_max_pkt_size[dev->alt])
805 unsigned int min_pkt_size = dev->field_size / 137; /* FIXME: empiric magic number */
806 em2820_coredbg("minimum isoc packet size: %u", min_pkt_size);
808 for (i = 1; i < EM2820_MAX_ALT; i += 2) /* FIXME: skip even alternate: why do they not work? */
809 if (dev->alt_max_pkt_size[i] >= min_pkt_size) {
816 if (dev->alt != prev_alt) {
817 dev->max_pkt_size = dev->alt_max_pkt_size[dev->alt];
818 em2820_coredbg("setting alternate %d with wMaxPacketSize=%u", dev->alt,
820 errCode = usb_set_interface(dev->udev, 0, dev->alt);
823 ("cannot change alternate number to %d (error=%i)\n",