// SPDX-License-Identifier: GPL-2.0 /* * The Virtual DVB test driver serves as a reference DVB driver and helps * validate the existing APIs in the media subsystem. It can also aid * developers working on userspace applications. * * Copyright (C) 2020 Daniel W. S. Almeida */ #define pr_fmt(fmt) … #include <linux/printk.h> #include <linux/ratelimit.h> #include <linux/string.h> #include <linux/types.h> #include "vidtv_common.h" /** * vidtv_memcpy() - wrapper routine to be used by MPEG-TS * generator, in order to avoid going past the * output buffer. * @to: Starting element to where a MPEG-TS packet will * be copied. * @to_offset: Starting position of the @to buffer to be filled. * @to_size: Size of the @to buffer. * @from: Starting element of the buffer to be copied. * @len: Number of elements to be copy from @from buffer * into @to+ @to_offset buffer. * * Note: * Real digital TV demod drivers should not have memcpy * wrappers. We use it here because emulating MPEG-TS * generation at kernelspace requires some extra care. * * Return: * Returns the number of bytes written */ u32 vidtv_memcpy(void *to, size_t to_offset, size_t to_size, const void *from, size_t len) { … } /** * vidtv_memset() - wrapper routine to be used by MPEG-TS * generator, in order to avoid going past the * output buffer. * @to: Starting element to set * @to_offset: Starting position of the @to buffer to be filled. * @to_size: Size of the @to buffer. * @c: The value to set the memory to. * @len: Number of elements to be copy from @from buffer * into @to+ @to_offset buffer. * * Note: * Real digital TV demod drivers should not have memset * wrappers. We use it here because emulating MPEG-TS * generation at kernelspace requires some extra care. * * Return: * Returns the number of bytes written */ u32 vidtv_memset(void *to, size_t to_offset, size_t to_size, const int c, size_t len) { … }