diff options
Diffstat (limited to 'drivers/media/usb/stk1160/stk1160-video.c')
| -rw-r--r-- | drivers/media/usb/stk1160/stk1160-video.c | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/drivers/media/usb/stk1160/stk1160-video.c b/drivers/media/usb/stk1160/stk1160-video.c new file mode 100644 index 000000000..2811f6128 --- /dev/null +++ b/drivers/media/usb/stk1160/stk1160-video.c @@ -0,0 +1,536 @@ +/* + * STK1160 driver + * + * Copyright (C) 2012 Ezequiel Garcia + * <elezegarcia--a.t--gmail.com> + * + * Based on Easycap driver by R.M. Thomas + * Copyright (C) 2010 R.M. Thomas + * <rmthomas--a.t--sciolus.org> + * + * 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 <linux/module.h> +#include <linux/usb.h> +#include <linux/slab.h> +#include <linux/ratelimit.h> + +#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; +} + |