I've probably got this wrong... I try to run several cameras with compressed streams (MJPEG) using maxpacket 3*1024 isoc-endpoints. EHCI should be able to transmit 8 microframes * 1024 bytes * 3 packets of data per frame (approx 24MB/sec). Two cameras work fine, but when I connect a third camera I get -ENOSPC from the scheduler. I don't get how the schedule can be full. One camera should be able to fit within one microframe. (3 * 1024b). That leaves atleast 7 microframes available if 100% of bandwith is used for isochronous transfers (not likely, but anyway). Debugfs lists the periodic schedule as (two cameras connected): /sys/kernel/debug/usb/ehci/fsl-ehci.0 cat periodic size = 512 1: qh256-0001/c3b0bd40 (h2 ep1in [1/0] q1 p1) 6: qh16-0001/c301d080 (h7 ep3in [1/0] q1 p8) 7: qh256-0001/c3b72180 (h8 ep1in [1/0] q1 p1) 9: qh16-0001/c30dd100 (h10 ep7in [1/0] q1 p16) 22: qh16-0001/c301d080 25: qh16-0001/c30dd100 38: qh16-0001/c301d080 41: qh16-0001/c30dd100 54: qh16-0001/c301d080 57: qh16-0001/c30dd100 70: qh16-0001/c301d080 73: qh16-0001/c30dd100 86: qh16-0001/c301d080 89: qh16-0001/c30dd100 102: qh16-0001/c301d080 105: qh16-0001/c30dd100 118: qh16-0001/c301d080 121: qh16-0001/c30dd100 134: qh16-0001/c301d080 137: qh16-0001/c30dd100 150: qh16-0001/c301d080 153: qh16-0001/c30dd100 166: qh16-0001/c301d080 169: qh16-0001/c30dd100 182: qh16-0001/c301d080 185: qh16-0001/c30dd100 198: qh16-0001/c301d080 201: qh16-0001/c30dd100 214: qh16-0001/c301d080 217: qh16-0001/c30dd100 230: qh16-0001/c301d080 233: qh16-0001/c30dd100 246: qh16-0001/c301d080 249: qh16-0001/c30dd100 257: qh256-0001/c3b0bd40 262: qh16-0001/c301d080 263: qh256-0001/c3b72180 265: qh16-0001/c30dd100 278: qh16-0001/c301d080 281: qh16-0001/c30dd100 294: qh16-0001/c301d080 297: qh16-0001/c30dd100 310: qh16-0001/c301d080 313: qh16-0001/c30dd100 326: qh16-0001/c301d080 329: qh16-0001/c30dd100 342: qh16-0001/c301d080 345: qh16-0001/c30dd100 358: qh16-0001/c301d080 361: qh16-0001/c30dd100 374: qh16-0001/c301d080 377: qh16-0001/c30dd100 390: qh16-0001/c301d080 393: qh16-0001/c30dd100 406: qh16-0001/c301d080 409: qh16-0001/c30dd100 422: qh16-0001/c301d080 425: qh16-0001/c30dd100 438: qh16-0001/c301d080 441: qh16-0001/c30dd100 453: itd/c32901e0 itd/c3290500 454: itd/c33c1d20 itd/c20ec000 qh16-0001/c301d080 455: itd/c20eca00 itd/c20d5320 456: itd/c32d08c0 itd/c32d05a0 457: itd/c20e83c0 itd/c20e86e0 qh16-0001/c30dd100 458: itd/c20e8460 itd/c20e8780 459: itd/c20ecaa0 itd/c20ec6e0 460: itd/c33c16e0 itd/c20ece60 461: itd/c33c1aa0 itd/c20ec140 462: itd/c21eaaa0 itd/c21eadc0 463: itd/c32900a0 itd/c32903c0 464: itd/c33c1960 itd/c20ecf00 465: itd/c3155dc0 itd/c3155aa0 466: itd/c20ec320 itd/c33cc0a0 467: itd/c3155c80 itd/c3155960 468: itd/c3155e60 itd/c3155b40 469: itd/c21ea1e0 itd/c21ea500 470: itd/c20ec780 itd/c33c1780 qh16-0001/c301d080 471: itd/c21eabe0 itd/c21ea8c0 472: itd/c21ea140 itd/c21ea460 473: qh16-0001/c30dd100 486: qh16-0001/c301d080 489: qh16-0001/c30dd100 502: qh16-0001/c301d080 505: qh16-0001/c30dd100 which is ~90 entries out of the 512 uframe schedule size. So why do I get -ENOSPC? -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
