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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 17:49:05 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-07 17:49:05 +0900
commit0b8e74c6f44094189dbe78baf4101acc7570c6af (patch)
tree6440561d09fb71ba5928664604ec92f29940be6b /drivers/media/dvb-core/dvb_ringbuffer.c
parent7f60ba388f5b9dd8b0da463b394412dace3ab814 (diff)
parentbd0d10498826ed150da5e4c45baf8b9c7088fb71 (diff)
downloadolio-linux-3.10-0b8e74c6f44094189dbe78baf4101acc7570c6af.tar.xz
olio-linux-3.10-0b8e74c6f44094189dbe78baf4101acc7570c6af.zip
Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull media updates from Mauro Carvalho Chehab: "The first part of the media updates for Kernel 3.7. This series contain: - A major tree renaming patch series: now, drivers are organized internally by their used bus, instead of by V4L2 and/or DVB API, providing a cleaner driver location for hybrid drivers that implement both APIs, and allowing to cleanup the Kconfig items and make them more intuitive for the end user; - Media Kernel developers are typically very lazy with their duties of keeping the MAINTAINERS entries for their drivers updated. As now the tree is more organized, we're doing an effort to add/update those entries for the drivers that aren't currently orphan; - Several DVB USB drivers got moved to a new DVB USB v2 core; the new core fixes several bugs (as the existing one that got bitroted). Now, suspend/resume finally started to work fine (at least with some devices - we should expect more work with regards to it); - added multistream support for DVB-T2, and unified the API for DVB-S2 and ISDB-S. Backward binary support is preserved; - as usual, a few new drivers, some V4L2 core improvements and lots of drivers improvements and fixes. There are some points to notice on this series: 1) you should expect a trivial merge conflict on your tree, with the removal of Documentation/feature-removal-schedule.txt: this series would be adding two additional entries there. I opted to not rebase it due to this recent change; 2) With regards to the PCTV 520e udev-related breakage, I opted to fix it in a way that the patches can be backported to 3.5 even without your firmware fix patch. This way, Greg doesn't need to rush backporting your patch (as there are still the firmware cache and firmware path customization issues to be addressed there). I'll send later a patch (likely after the end of the merge window) reverting the rest of the DRX-K async firmware request, fully restoring its original behaviour to allow media drivers to initialize everything serialized as before for 3.7 and upper. 3) I'm planning to work on this weekend to test the DMABUF patches for V4L2. The patches are on my queue for several Kernel cycles, but, up to now, there is/was no way to test the series locally. I have some concerns about this particular changeset with regards to security issues, and with regards to the replacement of the old VIDIOC_OVERLAY ioctl's that is broken on modern systems, due to GPU drivers change. The Overlay API allows direct PCI2PCI transfers from a media capture card into the GPU framebuffer, but its API is crappy. Also, the only existing X11 driver that implements it requires a XV extension that is not available anymore on modern drivers. The DMABUF can do the same thing, but with it is promising to be a properly-designed API. If I can successfully test this series and be happy with it, I should be asking you to pull them next week." * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (717 commits) em28xx: regression fix: use DRX-K sync firmware requests on em28xx drxk: allow loading firmware synchrousnously em28xx: Make all em28xx extensions to be initialized asynchronously [media] tda18271: properly report read errors in tda18271_get_id [media] tda18271: delay IR & RF calibration until init() if delay_cal is set [media] MAINTAINERS: add Michael Krufky as tda827x maintainer [media] MAINTAINERS: add Michael Krufky as tda8290 maintainer [media] MAINTAINERS: add Michael Krufky as cxusb maintainer [media] MAINTAINERS: add Michael Krufky as lg2160 maintainer [media] MAINTAINERS: add Michael Krufky as lgdt3305 maintainer [media] MAINTAINERS: add Michael Krufky as mxl111sf maintainer [media] MAINTAINERS: add Michael Krufky as mxl5007t maintainer [media] MAINTAINERS: add Michael Krufky as tda18271 maintainer [media] s5p-tv: Report only multi-plane capabilities in vidioc_querycap [media] s5p-mfc: Fix misplaced return statement in s5p_mfc_suspend() [media] exynos-gsc: Add missing static storage class specifiers [media] exynos-gsc: Remove <linux/version.h> header file inclusion [media] s5p-fimc: Fix incorrect condition in fimc_lite_reqbufs() [media] s5p-tv: Fix potential NULL pointer dereference error [media] s5k6aa: Fix possible NULL pointer dereference ...
Diffstat (limited to 'drivers/media/dvb-core/dvb_ringbuffer.c')
-rw-r--r--drivers/media/dvb-core/dvb_ringbuffer.c299
1 files changed, 299 insertions, 0 deletions
diff --git a/drivers/media/dvb-core/dvb_ringbuffer.c b/drivers/media/dvb-core/dvb_ringbuffer.c
new file mode 100644
index 00000000000..a5712cd7c65
--- /dev/null
+++ b/drivers/media/dvb-core/dvb_ringbuffer.c
@@ -0,0 +1,299 @@
+/*
+ *
+ * dvb_ringbuffer.c: ring buffer implementation for the dvb driver
+ *
+ * Copyright (C) 2003 Oliver Endriss
+ * Copyright (C) 2004 Andrew de Quincey
+ *
+ * based on code originally found in av7110.c & dvb_ci.c:
+ * Copyright (C) 1999-2003 Ralph Metzler
+ * & Marcus Metzler for convergence integrated media GmbH
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1
+ * 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 Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/string.h>
+#include <asm/uaccess.h>
+
+#include "dvb_ringbuffer.h"
+
+#define PKT_READY 0
+#define PKT_DISPOSED 1
+
+
+void dvb_ringbuffer_init(struct dvb_ringbuffer *rbuf, void *data, size_t len)
+{
+ rbuf->pread=rbuf->pwrite=0;
+ rbuf->data=data;
+ rbuf->size=len;
+ rbuf->error=0;
+
+ init_waitqueue_head(&rbuf->queue);
+
+ spin_lock_init(&(rbuf->lock));
+}
+
+
+
+int dvb_ringbuffer_empty(struct dvb_ringbuffer *rbuf)
+{
+ return (rbuf->pread==rbuf->pwrite);
+}
+
+
+
+ssize_t dvb_ringbuffer_free(struct dvb_ringbuffer *rbuf)
+{
+ ssize_t free;
+
+ free = rbuf->pread - rbuf->pwrite;
+ if (free <= 0)
+ free += rbuf->size;
+ return free-1;
+}
+
+
+
+ssize_t dvb_ringbuffer_avail(struct dvb_ringbuffer *rbuf)
+{
+ ssize_t avail;
+
+ avail = rbuf->pwrite - rbuf->pread;
+ if (avail < 0)
+ avail += rbuf->size;
+ return avail;
+}
+
+
+
+void dvb_ringbuffer_flush(struct dvb_ringbuffer *rbuf)
+{
+ rbuf->pread = rbuf->pwrite;
+ rbuf->error = 0;
+}
+EXPORT_SYMBOL(dvb_ringbuffer_flush);
+
+void dvb_ringbuffer_reset(struct dvb_ringbuffer *rbuf)
+{
+ rbuf->pread = rbuf->pwrite = 0;
+ rbuf->error = 0;
+}
+
+void dvb_ringbuffer_flush_spinlock_wakeup(struct dvb_ringbuffer *rbuf)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rbuf->lock, flags);
+ dvb_ringbuffer_flush(rbuf);
+ spin_unlock_irqrestore(&rbuf->lock, flags);
+
+ wake_up(&rbuf->queue);
+}
+
+ssize_t dvb_ringbuffer_read_user(struct dvb_ringbuffer *rbuf, u8 __user *buf, size_t len)
+{
+ size_t todo = len;
+ size_t split;
+
+ split = (rbuf->pread + len > rbuf->size) ? rbuf->size - rbuf->pread : 0;
+ if (split > 0) {
+ if (copy_to_user(buf, rbuf->data+rbuf->pread, split))
+ return -EFAULT;
+ buf += split;
+ todo -= split;
+ rbuf->pread = 0;
+ }
+ if (copy_to_user(buf, rbuf->data+rbuf->pread, todo))
+ return -EFAULT;
+
+ rbuf->pread = (rbuf->pread + todo) % rbuf->size;
+
+ return len;
+}
+
+void dvb_ringbuffer_read(struct dvb_ringbuffer *rbuf, u8 *buf, size_t len)
+{
+ size_t todo = len;
+ size_t split;
+
+ split = (rbuf->pread + len > rbuf->size) ? rbuf->size - rbuf->pread : 0;
+ if (split > 0) {
+ memcpy(buf, rbuf->data+rbuf->pread, split);
+ buf += split;
+ todo -= split;
+ rbuf->pread = 0;
+ }
+ memcpy(buf, rbuf->data+rbuf->pread, todo);
+
+ rbuf->pread = (rbuf->pread + todo) % rbuf->size;
+}
+
+
+ssize_t dvb_ringbuffer_write(struct dvb_ringbuffer *rbuf, const u8 *buf, size_t len)
+{
+ size_t todo = len;
+ size_t split;
+
+ split = (rbuf->pwrite + len > rbuf->size) ? rbuf->size - rbuf->pwrite : 0;
+
+ if (split > 0) {
+ memcpy(rbuf->data+rbuf->pwrite, buf, split);
+ buf += split;
+ todo -= split;
+ rbuf->pwrite = 0;
+ }
+ memcpy(rbuf->data+rbuf->pwrite, buf, todo);
+ rbuf->pwrite = (rbuf->pwrite + todo) % rbuf->size;
+
+ return len;
+}
+
+ssize_t dvb_ringbuffer_pkt_write(struct dvb_ringbuffer *rbuf, u8* buf, size_t len)
+{
+ int status;
+ ssize_t oldpwrite = rbuf->pwrite;
+
+ DVB_RINGBUFFER_WRITE_BYTE(rbuf, len >> 8);
+ DVB_RINGBUFFER_WRITE_BYTE(rbuf, len & 0xff);
+ DVB_RINGBUFFER_WRITE_BYTE(rbuf, PKT_READY);
+ status = dvb_ringbuffer_write(rbuf, buf, len);
+
+ if (status < 0) rbuf->pwrite = oldpwrite;
+ return status;
+}
+
+ssize_t dvb_ringbuffer_pkt_read_user(struct dvb_ringbuffer *rbuf, size_t idx,
+ int offset, u8 __user *buf, size_t len)
+{
+ size_t todo;
+ size_t split;
+ size_t pktlen;
+
+ pktlen = rbuf->data[idx] << 8;
+ pktlen |= rbuf->data[(idx + 1) % rbuf->size];
+ if (offset > pktlen) return -EINVAL;
+ if ((offset + len) > pktlen) len = pktlen - offset;
+
+ idx = (idx + DVB_RINGBUFFER_PKTHDRSIZE + offset) % rbuf->size;
+ todo = len;
+ split = ((idx + len) > rbuf->size) ? rbuf->size - idx : 0;
+ if (split > 0) {
+ if (copy_to_user(buf, rbuf->data+idx, split))
+ return -EFAULT;
+ buf += split;
+ todo -= split;
+ idx = 0;
+ }
+ if (copy_to_user(buf, rbuf->data+idx, todo))
+ return -EFAULT;
+
+ return len;
+}
+
+ssize_t dvb_ringbuffer_pkt_read(struct dvb_ringbuffer *rbuf, size_t idx,
+ int offset, u8* buf, size_t len)
+{
+ size_t todo;
+ size_t split;
+ size_t pktlen;
+
+ pktlen = rbuf->data[idx] << 8;
+ pktlen |= rbuf->data[(idx + 1) % rbuf->size];
+ if (offset > pktlen) return -EINVAL;
+ if ((offset + len) > pktlen) len = pktlen - offset;
+
+ idx = (idx + DVB_RINGBUFFER_PKTHDRSIZE + offset) % rbuf->size;
+ todo = len;
+ split = ((idx + len) > rbuf->size) ? rbuf->size - idx : 0;
+ if (split > 0) {
+ memcpy(buf, rbuf->data+idx, split);
+ buf += split;
+ todo -= split;
+ idx = 0;
+ }
+ memcpy(buf, rbuf->data+idx, todo);
+ return len;
+}
+
+void dvb_ringbuffer_pkt_dispose(struct dvb_ringbuffer *rbuf, size_t idx)
+{
+ size_t pktlen;
+
+ rbuf->data[(idx + 2) % rbuf->size] = PKT_DISPOSED;
+
+ // clean up disposed packets
+ while(dvb_ringbuffer_avail(rbuf) > DVB_RINGBUFFER_PKTHDRSIZE) {
+ if (DVB_RINGBUFFER_PEEK(rbuf, 2) == PKT_DISPOSED) {
+ pktlen = DVB_RINGBUFFER_PEEK(rbuf, 0) << 8;
+ pktlen |= DVB_RINGBUFFER_PEEK(rbuf, 1);
+ DVB_RINGBUFFER_SKIP(rbuf, pktlen + DVB_RINGBUFFER_PKTHDRSIZE);
+ } else {
+ // first packet is not disposed, so we stop cleaning now
+ break;
+ }
+ }
+}
+
+ssize_t dvb_ringbuffer_pkt_next(struct dvb_ringbuffer *rbuf, size_t idx, size_t* pktlen)
+{
+ int consumed;
+ int curpktlen;
+ int curpktstatus;
+
+ if (idx == -1) {
+ idx = rbuf->pread;
+ } else {
+ curpktlen = rbuf->data[idx] << 8;
+ curpktlen |= rbuf->data[(idx + 1) % rbuf->size];
+ idx = (idx + curpktlen + DVB_RINGBUFFER_PKTHDRSIZE) % rbuf->size;
+ }
+
+ consumed = (idx - rbuf->pread) % rbuf->size;
+
+ while((dvb_ringbuffer_avail(rbuf) - consumed) > DVB_RINGBUFFER_PKTHDRSIZE) {
+
+ curpktlen = rbuf->data[idx] << 8;
+ curpktlen |= rbuf->data[(idx + 1) % rbuf->size];
+ curpktstatus = rbuf->data[(idx + 2) % rbuf->size];
+
+ if (curpktstatus == PKT_READY) {
+ *pktlen = curpktlen;
+ return idx;
+ }
+
+ consumed += curpktlen + DVB_RINGBUFFER_PKTHDRSIZE;
+ idx = (idx + curpktlen + DVB_RINGBUFFER_PKTHDRSIZE) % rbuf->size;
+ }
+
+ // no packets available
+ return -1;
+}
+
+
+
+EXPORT_SYMBOL(dvb_ringbuffer_init);
+EXPORT_SYMBOL(dvb_ringbuffer_empty);
+EXPORT_SYMBOL(dvb_ringbuffer_free);
+EXPORT_SYMBOL(dvb_ringbuffer_avail);
+EXPORT_SYMBOL(dvb_ringbuffer_flush_spinlock_wakeup);
+EXPORT_SYMBOL(dvb_ringbuffer_read_user);
+EXPORT_SYMBOL(dvb_ringbuffer_read);
+EXPORT_SYMBOL(dvb_ringbuffer_write);