kernel-ark/include/asm-arm/arch-imx/imx-dma.h
Pavel Pisa 999331af45 [ARM] 3444/1: i.MX: Scatter-gather DMA emulation for i.MX/MX1
Patch from Pavel Pisa

This patch contains simplified set of changes to add scatter-gather
emulation capability into MX1 DMA support. The result should
be still usable for next combination of DMA transfers
  Statter-Gather/linear/2D/FIFO to linear/2D/FIFO and
  linear/2D/FIFO to Statter-Gather/2D/FIFO
The patch corrects channel priority allocation to be compatible
with MX1 hardware implementation.
Previous code has not been adapted from its PXA original.

Signed-off-by: Pavel Pisa <pisa@cmp.felk.cvut.cz>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2006-04-02 16:58:37 +01:00

91 lines
2.9 KiB
C

/*
* linux/include/asm-arm/imxads/dma.h
*
* Copyright (C) 1997,1998 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU 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 <asm/dma.h>
#ifndef __ASM_ARCH_IMX_DMA_H
#define __ASM_ARCH_IMX_DMA_H
#define IMX_DMA_CHANNELS 11
/*
* struct imx_dma_channel - i.MX specific DMA extension
* @name: name specified by DMA client
* @irq_handler: client callback for end of transfer
* @err_handler: client callback for error condition
* @data: clients context data for callbacks
* @dma_mode: direction of the transfer %DMA_MODE_READ or %DMA_MODE_WRITE
* @sg: pointer to the actual read/written chunk for scatter-gather emulation
* @sgbc: counter of processed bytes in the actual read/written chunk
* @resbytes: total residual number of bytes to transfer
* (it can be lower or same as sum of SG mapped chunk sizes)
* @sgcount: number of chunks to be read/written
*
* Structure is used for IMX DMA processing. It would be probably good
* @struct dma_struct in the future for external interfacing and use
* @struct imx_dma_channel only as extension to it.
*/
struct imx_dma_channel {
const char *name;
void (*irq_handler) (int, void *, struct pt_regs *);
void (*err_handler) (int, void *, struct pt_regs *);
void *data;
dmamode_t dma_mode;
struct scatterlist *sg;
unsigned int sgbc;
unsigned int sgcount;
unsigned int resbytes;
int dma_num;
};
extern struct imx_dma_channel imx_dma_channels[IMX_DMA_CHANNELS];
/* The type to distinguish channel numbers parameter from ordinal int type */
typedef int imx_dmach_t;
int
imx_dma_setup_single(imx_dmach_t dma_ch, dma_addr_t dma_address,
unsigned int dma_length, unsigned int dev_addr, dmamode_t dmamode);
int
imx_dma_setup_sg(imx_dmach_t dma_ch,
struct scatterlist *sg, unsigned int sgcount, unsigned int dma_length,
unsigned int dev_addr, dmamode_t dmamode);
int
imx_dma_setup_handlers(imx_dmach_t dma_ch,
void (*irq_handler) (int, void *, struct pt_regs *),
void (*err_handler) (int, void *, struct pt_regs *), void *data);
void imx_dma_enable(imx_dmach_t dma_ch);
void imx_dma_disable(imx_dmach_t dma_ch);
int imx_dma_request(imx_dmach_t dma_ch, const char *name);
void imx_dma_free(imx_dmach_t dma_ch);
int imx_dma_request_by_prio(imx_dmach_t *pdma_ch, const char *name, imx_dma_prio prio);
#endif /* _ASM_ARCH_IMX_DMA_H */