1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/media/usb/pwc/pwc-uncompress.c b/drivers/media/usb/pwc/pwc-uncompress.c
new file mode 100644
index 0000000000..cf2591a967
--- /dev/null
+++ b/drivers/media/usb/pwc/pwc-uncompress.c
@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Linux driver for Philips webcam
+   Decompression frontend.
+   (C) 1999-2003 Nemosoft Unv.
+   (C) 2004-2006 Luc Saillard (luc@saillard.org)
+
+   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
+   driver and thus may have bugs that are not present in the original version.
+   Please send bug reports and support requests to <luc@saillard.org>.
+   The decompression routines have been implemented by reverse-engineering the
+   Nemosoft binary pwcx module. Caveat emptor.
+*/
+
+#include <asm/current.h>
+#include <asm/types.h>
+
+#include "pwc.h"
+#include "pwc-dec1.h"
+#include "pwc-dec23.h"
+
+int pwc_decompress(struct pwc_device *pdev, struct pwc_frame_buf *fbuf)
+{
+	int n, line, col;
+	void *yuv, *image;
+	u16 *src;
+	u16 *dsty, *dstu, *dstv;
+
+	image = vb2_plane_vaddr(&fbuf->vb.vb2_buf, 0);
+
+	yuv = fbuf->data + pdev->frame_header_size;  /* Skip header */
+
+	/* Raw format; that's easy... */
+	if (pdev->pixfmt != V4L2_PIX_FMT_YUV420)
+	{
+		struct pwc_raw_frame *raw_frame = image;
+		raw_frame->type = cpu_to_le16(pdev->type);
+		raw_frame->vbandlength = cpu_to_le16(pdev->vbandlength);
+			/* cmd_buf is always 4 bytes, but sometimes, only the
+			 * first 3 bytes is filled (Nala case). We can
+			 * determine this using the type of the webcam */
+		memcpy(raw_frame->cmd, pdev->cmd_buf, 4);
+		memcpy(raw_frame->rawframe, yuv, pdev->frame_size);
+		vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0,
+			struct_size(raw_frame, rawframe, pdev->frame_size));
+		return 0;
+	}
+
+	vb2_set_plane_payload(&fbuf->vb.vb2_buf, 0,
+			      pdev->width * pdev->height * 3 / 2);
+
+	if (pdev->vbandlength == 0) {
+		/* Uncompressed mode.
+		 *
+		 * We do some byte shuffling here to go from the
+		 * native format to YUV420P.
+		 */
+		src = (u16 *)yuv;
+		n = pdev->width * pdev->height;
+		dsty = (u16 *)(image);
+		dstu = (u16 *)(image + n);
+		dstv = (u16 *)(image + n + n / 4);
+
+		for (line = 0; line < pdev->height; line++) {
+			for (col = 0; col < pdev->width; col += 4) {
+				*dsty++ = *src++;
+				*dsty++ = *src++;
+				if (line & 1)
+					*dstv++ = *src++;
+				else
+					*dstu++ = *src++;
+			}
+		}
+
+		return 0;
+	}
+
+	/*
+	 * Compressed;
+	 * the decompressor routines will write the data in planar format
+	 * immediately.
+	 */
+	if (DEVICE_USE_CODEC1(pdev->type)) {
+
+		/* TODO & FIXME */
+		PWC_ERROR("This chipset is not supported for now\n");
+		return -ENXIO; /* No such device or address: missing decompressor */
+
+	} else {
+		pwc_dec23_decompress(pdev, yuv, image);
+	}
+	return 0;
+}