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b50e7fe993
Before this patch, vivi were simulating a scatter gather DMA transfer. While this is academic, showing how stuff really works on a real PCI device, this means a non-optimized code. There are only two memory models that vivi implements: 1) kernel alloced memory. This is also used by read() method. On this case, a vmalloc32 buffer is allocated at kernel; 2) userspace allocated memory. This is used by most userspace apps. video-buf will store this pointer. a simple copy_to_user is enough to transfer data. The third memory model scenario supported by video-buf is overlay mode. This model is not implemented on vivi and unlikely to be implemented on newer drivers, since now, most userspace apps do some post-processing (like de-interlacing). After this patch, some cleanups may be done at video-buf.c to avoid allocating pages, when the driver doesn't need a PCI buffer. This is the case of vivi and usb drivers. Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org> |
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| common | ||
| dvb | ||
| radio | ||
| video | ||
| Kconfig | ||
| Makefile | ||