1 files changed, 526 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..202b084f6
--- /dev/null
+++ b/drivers/media/usb/stk1160/stk1160-video.c
@@ -0,0 +1,526 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * 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>
+ */
+
+#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;
+}
+