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1/* SPDX-License-Identifier: GPL-2.0+ */2/*3 * COMEDI ISA DMA support functions4 * Copyright (c) 2014 H Hartley Sweeten <hsweeten@visionengravers.com>5 */6 7#ifndef _COMEDI_ISADMA_H8#define _COMEDI_ISADMA_H9 10#include <linux/types.h>11 12struct comedi_device;13struct device;14 15/*16 * These are used to avoid issues when <asm/dma.h> and the DMA_MODE_17 * defines are not available.18 */19#define COMEDI_ISADMA_READ 020#define COMEDI_ISADMA_WRITE 121 22/**23 * struct comedi_isadma_desc - cookie for ISA DMA24 * @virt_addr: virtual address of buffer25 * @hw_addr: hardware (bus) address of buffer26 * @chan: DMA channel27 * @maxsize: allocated size of buffer (in bytes)28 * @size: transfer size (in bytes)29 * @mode: DMA_MODE_READ or DMA_MODE_WRITE30 */31struct comedi_isadma_desc {32 void *virt_addr;33 dma_addr_t hw_addr;34 unsigned int chan;35 unsigned int maxsize;36 unsigned int size;37 char mode;38};39 40/**41 * struct comedi_isadma - ISA DMA data42 * @dev: device to allocate non-coherent memory for43 * @desc: cookie for each DMA buffer44 * @n_desc: the number of cookies45 * @cur_dma: the current cookie in use46 * @chan: the first DMA channel requested47 * @chan2: the second DMA channel requested48 */49struct comedi_isadma {50 struct device *dev;51 struct comedi_isadma_desc *desc;52 int n_desc;53 int cur_dma;54 unsigned int chan;55 unsigned int chan2;56};57 58#if IS_ENABLED(CONFIG_ISA_DMA_API)59 60void comedi_isadma_program(struct comedi_isadma_desc *desc);61unsigned int comedi_isadma_disable(unsigned int dma_chan);62unsigned int comedi_isadma_disable_on_sample(unsigned int dma_chan,63 unsigned int size);64unsigned int comedi_isadma_poll(struct comedi_isadma *dma);65void comedi_isadma_set_mode(struct comedi_isadma_desc *desc, char dma_dir);66 67struct comedi_isadma *comedi_isadma_alloc(struct comedi_device *dev,68 int n_desc, unsigned int dma_chan1,69 unsigned int dma_chan2,70 unsigned int maxsize, char dma_dir);71void comedi_isadma_free(struct comedi_isadma *dma);72 73#else /* !IS_ENABLED(CONFIG_ISA_DMA_API) */74 75static inline void comedi_isadma_program(struct comedi_isadma_desc *desc)76{77}78 79static inline unsigned int comedi_isadma_disable(unsigned int dma_chan)80{81 return 0;82}83 84static inline unsigned int85comedi_isadma_disable_on_sample(unsigned int dma_chan, unsigned int size)86{87 return 0;88}89 90static inline unsigned int comedi_isadma_poll(struct comedi_isadma *dma)91{92 return 0;93}94 95static inline void comedi_isadma_set_mode(struct comedi_isadma_desc *desc,96 char dma_dir)97{98}99 100static inline struct comedi_isadma *101comedi_isadma_alloc(struct comedi_device *dev, int n_desc,102 unsigned int dma_chan1, unsigned int dma_chan2,103 unsigned int maxsize, char dma_dir)104{105 return NULL;106}107 108static inline void comedi_isadma_free(struct comedi_isadma *dma)109{110}111 112#endif /* !IS_ENABLED(CONFIG_ISA_DMA_API) */113 114#endif /* #ifndef _COMEDI_ISADMA_H */115