/* * STK1160 driver * * Copyright (C) 2012 Ezequiel Garcia * * * Based on Easycap driver by R.M. Thomas * Copyright (C) 2010 R.M. Thomas * * * 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. * */ #include #include #include #include #include "stk1160.h" static unsigned int debug; module_param(debug, int, 0644); MODULE_PARM_DESC(debug, "enable debug messages"); static inline void print_err_status(struct stk1160 *dev, int packet, int status) { char *errmsg = "Unknown"; switch (status) { case -ENOENT: errmsg = "unlinked synchronously"; break; case -ECONNRESET: errmsg = "unlinked asynchronously"; break; case -ENOSR: errmsg = "Buffer error (overrun)"; break; case -EPIPE: errmsg = "Stalled (device not responding)"; break; case -EOVERFLOW: errmsg = "Babble (bad cable?)"; break; case -EPROTO: errmsg = "Bit-stuff error (bad cable?)"; break; case -EILSEQ: errmsg = "CRC/Timeout (could be anything)"; break; case -ETIME: errmsg = "Device does not respond"; break; } if (packet < 0) printk_ratelimited(KERN_WARNING "URB status %d [%s].\n", status, errmsg); else printk_ratelimited(KERN_INFO "URB packet %d, status %d [%s].\n", packet, status, errmsg); } static inline struct stk1160_buffer *stk1160_next_buffer(struct stk1160 *dev) { struct stk1160_buffer *buf = NULL; unsigned long flags = 0; /* Current buffer must be NULL when this functions gets called */ WARN_ON(dev->isoc_ctl.buf); spin_lock_irqsave(&dev->buf_lock, flags); if (!list_empty(&dev->avail_bufs)) { buf = list_first_entry(&dev->avail_bufs, struct stk1160_buffer, list); list_del(&buf->list); } spin_unlock_irqrestore(&dev->buf_lock, flags); return buf; } static inline void stk1160_buffer_done(struct stk1160 *dev) { struct stk1160_buffer *buf = dev->isoc_ctl.buf; buf->vb.sequence = dev->sequence++; buf->vb.field = V4L2_FIELD_INTERLACED; buf->vb.vb2_buf.timestamp = ktime_get_ns(); vb2_set_plane_payload(&buf->vb.vb2_buf, 0, buf->bytesused); vb2_buffer_done(&buf->vb.vb2_buf, VB2_BUF_STATE_DONE); dev->isoc_ctl.buf = NULL; } static inline void stk1160_copy_video(struct stk1160 *dev, u8 *src, int len) { int linesdone, lineoff, lencopy; int bytesperline = dev->width * 2; struct stk1160_buffer *buf = dev->isoc_ctl.buf; u8 *dst = buf->mem; int remain; /* * TODO: These stk1160_dbg are very spammy! * We should 1) check why we are getting them * and 2) add ratelimit. * * UPDATE: One of the reasons (the only one?) for getting these * is incorrect standard (mismatch between expected and configured). * So perhaps, we could add a counter for errors. When the counter * reaches some value, we simply stop streaming. */ len -= 4; src += 4; remain = len; linesdone = buf->pos / bytesperline; lineoff = buf->pos % bytesperline; /* offset in current line */ if (!buf->odd) dst += bytesperline; /* Multiply linesdone by two, to take account of the other field */ dst += linesdone * bytesperline * 2 + lineoff; /* Copy the remaining of current line */ if (remain < (bytesperline - lineoff)) lencopy = remain; else lencopy = bytesperline - lineoff; /* * Check if we have enough space left in the buffer. * In that case, we force loop exit after copy. */ if (lencopy > buf->bytesused - buf->length) { lencopy = buf->bytesused - buf->length; remain = lencopy; } /* Check if the copy is done */ if (lencopy == 0 || remain == 0) return; /* Let the bug hunt begin! sanity checks! */ if (lencopy < 0) { stk1160_dbg("copy skipped: negative lencopy\n"); return; } if ((unsigned long)dst + lencopy > (unsigned long)buf->mem + buf->length) { printk_ratelimited(KERN_WARNING "stk1160: buffer overflow detected\n"); return; } memcpy(dst, src, lencopy); buf->bytesused += lencopy; buf->pos += lencopy; remain -= lencopy; /* Copy current field line by line, interlacing with the other field */ while (remain > 0) { dst += lencopy + bytesperline; src += lencopy; /* Copy one line at a time */ if (remain < bytesperline) lencopy = remain; else lencopy = bytesperline; /* * Check if we have enough space left in the buffer. * In that case, we force loop exit after copy. */ if (lencopy > buf->bytesused - buf->length) { lencopy = buf->bytesused - buf->length; remain = lencopy; } /* Check if the copy is done */ if (lencopy == 0 || remain == 0) return; if (lencopy < 0) { printk_ratelimited(KERN_WARNING "stk1160: negative lencopy detected\n"); return; } if ((unsigned long)dst + lencopy > (unsigned long)buf->mem + buf->length) { printk_ratelimited(KERN_WARNING "stk1160: buffer overflow detected\n"); return; } memcpy(dst, src, lencopy); remain -= lencopy; buf->bytesused += lencopy; buf->pos += lencopy; } } /* * Controls the isoc copy of each urb packet */ static void stk1160_process_isoc(struct stk1160 *dev, struct urb *urb) { int i, len, status; u8 *p; if (!dev) { stk1160_warn("%s called with null device\n", __func__); return; } if (urb->status < 0) { /* Print status and drop current packet (or field?) */ print_err_status(dev, -1, urb->status); return; } for (i = 0; i < urb->number_of_packets; i++) { status = urb->iso_frame_desc[i].status; if (status < 0) { print_err_status(dev, i, status); continue; } /* Get packet actual length and pointer to data */ p = urb->transfer_buffer + urb->iso_frame_desc[i].offset; len = urb->iso_frame_desc[i].actual_length; /* Empty packet */ if (len <= 4) continue; /* * An 8-byte packet sequence means end of field. * So if we don't have any packet, we start receiving one now * and if we do have a packet, then we are done with it. * * These end of field packets are always 0xc0 or 0x80, * but not always 8-byte long so we don't check packet length. */ if (p[0] == 0xc0) { /* * If first byte is 0xc0 then we received * second field, and frame has ended. */ if (dev->isoc_ctl.buf != NULL) stk1160_buffer_done(dev); dev->isoc_ctl.buf = stk1160_next_buffer(dev); if (dev->isoc_ctl.buf == NULL) return; } /* * If we don't have a buffer here, then it means we * haven't found the start mark sequence. */ if (dev->isoc_ctl.buf == NULL) continue; if (p[0] == 0xc0 || p[0] == 0x80) { /* We set next packet parity and * continue to get next one */ dev->isoc_ctl.buf->odd = *p & 0x40; dev->isoc_ctl.buf->pos = 0; continue; } stk1160_copy_video(dev, p, len); } } /* * IRQ callback, called by URB callback */ static void stk1160_isoc_irq(struct urb *urb) { int i, rc; struct stk1160 *dev = urb->context; switch (urb->status) { case 0: break; case -ECONNRESET: /* kill */ case -ENOENT: case -ESHUTDOWN: /* TODO: check uvc driver: he frees the queue here */ return; default: stk1160_err("urb error! status %d\n", urb->status); return; } stk1160_process_isoc(dev, urb); /* Reset urb buffers */ for (i = 0; i < urb->number_of_packets; i++) { urb->iso_frame_desc[i].status = 0; urb->iso_frame_desc[i].actual_length = 0; } rc = usb_submit_urb(urb, GFP_ATOMIC); if (rc) stk1160_err("urb re-submit failed (%d)\n", rc); } /* * Cancel urbs * This function can't be called in atomic context */ void stk1160_cancel_isoc(struct stk1160 *dev) { int i, num_bufs = dev->isoc_ctl.num_bufs; /* * This check is not necessary, but we add it * to avoid a spurious debug message */ if (!num_bufs) return; stk1160_dbg("killing %d urbs...\n", num_bufs); for (i = 0; i < num_bufs; i++) { /* * To kill urbs we can't be in atomic context. * We don't care for NULL pointer since * usb_kill_urb allows it. */ usb_kill_urb(dev->isoc_ctl.urb[i]); } stk1160_dbg("all urbs killed\n"); } /* * Releases urb and transfer buffers * Obviusly, associated urb must be killed before releasing it. */ void stk1160_free_isoc(struct stk1160 *dev) { struct urb *urb; int i, num_bufs = dev->isoc_ctl.num_bufs; stk1160_dbg("freeing %d urb buffers...\n", num_bufs); for (i = 0; i < num_bufs; i++) { urb = dev->isoc_ctl.urb[i]; if (urb) { if (dev->isoc_ctl.transfer_buffer[i]) { #ifndef CONFIG_DMA_NONCOHERENT usb_free_coherent(dev->udev, urb->transfer_buffer_length, dev->isoc_ctl.transfer_buffer[i], urb->transfer_dma); #else kfree(dev->isoc_ctl.transfer_buffer[i]); #endif } usb_free_urb(urb); dev->isoc_ctl.urb[i] = NULL; } dev->isoc_ctl.transfer_buffer[i] = NULL; } kfree(dev->isoc_ctl.urb); kfree(dev->isoc_ctl.transfer_buffer); dev->isoc_ctl.urb = NULL; dev->isoc_ctl.transfer_buffer = NULL; dev->isoc_ctl.num_bufs = 0; stk1160_dbg("all urb buffers freed\n"); } /* * Helper for cancelling and freeing urbs * This function can't be called in atomic context */ void stk1160_uninit_isoc(struct stk1160 *dev) { stk1160_cancel_isoc(dev); stk1160_free_isoc(dev); } /* * Allocate URBs */ int stk1160_alloc_isoc(struct stk1160 *dev) { struct urb *urb; int i, j, k, sb_size, max_packets, num_bufs; /* * It may be necessary to release isoc here, * since isoc are only released on disconnection. * (see new_pkt_size flag) */ if (dev->isoc_ctl.num_bufs) stk1160_uninit_isoc(dev); stk1160_dbg("allocating urbs...\n"); num_bufs = STK1160_NUM_BUFS; max_packets = STK1160_NUM_PACKETS; sb_size = max_packets * dev->max_pkt_size; dev->isoc_ctl.buf = NULL; dev->isoc_ctl.max_pkt_size = dev->max_pkt_size; dev->isoc_ctl.urb = kcalloc(num_bufs, sizeof(void *), GFP_KERNEL); if (!dev->isoc_ctl.urb) { stk1160_err("out of memory for urb array\n"); return -ENOMEM; } dev->isoc_ctl.transfer_buffer = kcalloc(num_bufs, sizeof(void *), GFP_KERNEL); if (!dev->isoc_ctl.transfer_buffer) { stk1160_err("out of memory for usb transfers\n"); kfree(dev->isoc_ctl.urb); return -ENOMEM; } /* allocate urbs and transfer buffers */ for (i = 0; i < num_bufs; i++) { urb = usb_alloc_urb(max_packets, GFP_KERNEL); if (!urb) goto free_i_bufs; dev->isoc_ctl.urb[i] = urb; #ifndef CONFIG_DMA_NONCOHERENT dev->isoc_ctl.transfer_buffer[i] = usb_alloc_coherent(dev->udev, sb_size, GFP_KERNEL, &urb->transfer_dma); #else dev->isoc_ctl.transfer_buffer[i] = kmalloc(sb_size, GFP_KERNEL); #endif if (!dev->isoc_ctl.transfer_buffer[i]) { stk1160_err("cannot alloc %d bytes for tx[%d] buffer\n", sb_size, i); /* Not enough transfer buffers, so just give up */ if (i < STK1160_MIN_BUFS) goto free_i_bufs; goto nomore_tx_bufs; } memset(dev->isoc_ctl.transfer_buffer[i], 0, sb_size); /* * FIXME: Where can I get the endpoint? */ urb->dev = dev->udev; urb->pipe = usb_rcvisocpipe(dev->udev, STK1160_EP_VIDEO); urb->transfer_buffer = dev->isoc_ctl.transfer_buffer[i]; urb->transfer_buffer_length = sb_size; urb->complete = stk1160_isoc_irq; urb->context = dev; urb->interval = 1; urb->start_frame = 0; urb->number_of_packets = max_packets; #ifndef CONFIG_DMA_NONCOHERENT urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP; #else urb->transfer_flags = URB_ISO_ASAP; #endif k = 0; for (j = 0; j < max_packets; j++) { urb->iso_frame_desc[j].offset = k; urb->iso_frame_desc[j].length = dev->isoc_ctl.max_pkt_size; k += dev->isoc_ctl.max_pkt_size; } } stk1160_dbg("%d urbs allocated\n", num_bufs); /* At last we can say we have some buffers */ dev->isoc_ctl.num_bufs = num_bufs; return 0; nomore_tx_bufs: /* * Failed to allocate desired buffer count. However, we may have * enough to work fine, so we just free the extra urb, * store the allocated count and keep going, fingers crossed! */ usb_free_urb(dev->isoc_ctl.urb[i]); dev->isoc_ctl.urb[i] = NULL; stk1160_warn("%d urbs allocated. Trying to continue...\n", i - 1); dev->isoc_ctl.num_bufs = i - 1; return 0; free_i_bufs: /* Save the allocated buffers so far, so we can properly free them */ dev->isoc_ctl.num_bufs = i+1; stk1160_free_isoc(dev); return -ENOMEM; }