--- /dev/null
+/*
+ * 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 synchronuously";
+ break;
+ case -ECONNRESET:
+ errmsg = "unlinked asynchronuously";
+ 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;
+
+ dev->field_count++;
+
+ buf->vb.v4l2_buf.sequence = dev->field_count >> 1;
+ buf->vb.v4l2_buf.field = V4L2_FIELD_INTERLACED;
+ buf->vb.v4l2_buf.bytesused = buf->bytesused;
+ v4l2_get_timestamp(&buf->vb.v4l2_buf.timestamp);
+
+ vb2_set_plane_payload(&buf->vb, 0, buf->bytesused);
+ vb2_buffer_done(&buf->vb, 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 = kzalloc(sizeof(void *)*num_bufs, GFP_KERNEL);
+ if (!dev->isoc_ctl.urb) {
+ stk1160_err("out of memory for urb array\n");
+ return -ENOMEM;
+ }
+
+ dev->isoc_ctl.transfer_buffer = kzalloc(sizeof(void *)*num_bufs,
+ 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) {
+ stk1160_err("cannot alloc urb[%d]\n", i);
+ 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;
+}
+
Code Review / kvmfornfv.git / blobdiff