linux/drivers/dma/shdma.h
Guennadi Liakhovetski 7a1cd9ad87 dma: shdma: transfer based runtime PM
Currently the shdma dmaengine driver uses runtime PM to save power, when
no channel on the specific controller is requested by a user. This patch
switches the driver to count individual DMA transfers. That way the
controller can be powered down between transfers, even if some of its
channels are in use.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2011-09-28 10:07:40 +05:30

67 lines
2 KiB
C

/*
* Renesas SuperH DMA Engine support
*
* Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
* Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
*
* This 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.
*
*/
#ifndef __DMA_SHDMA_H
#define __DMA_SHDMA_H
#include <linux/dmaengine.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#define SH_DMAC_MAX_CHANNELS 20
#define SH_DMA_SLAVE_NUMBER 256
#define SH_DMA_TCR_MAX 0x00FFFFFF /* 16MB */
struct device;
enum dmae_pm_state {
DMAE_PM_ESTABLISHED,
DMAE_PM_BUSY,
DMAE_PM_PENDING,
};
struct sh_dmae_chan {
dma_cookie_t completed_cookie; /* The maximum cookie completed */
spinlock_t desc_lock; /* Descriptor operation lock */
struct list_head ld_queue; /* Link descriptors queue */
struct list_head ld_free; /* Link descriptors free */
struct dma_chan common; /* DMA common channel */
struct device *dev; /* Channel device */
struct tasklet_struct tasklet; /* Tasklet */
int descs_allocated; /* desc count */
int xmit_shift; /* log_2(bytes_per_xfer) */
int irq;
int id; /* Raw id of this channel */
u32 __iomem *base;
char dev_id[16]; /* unique name per DMAC of channel */
int pm_error;
enum dmae_pm_state pm_state;
};
struct sh_dmae_device {
struct dma_device common;
struct sh_dmae_chan *chan[SH_DMAC_MAX_CHANNELS];
struct sh_dmae_pdata *pdata;
struct list_head node;
u32 __iomem *chan_reg;
u16 __iomem *dmars;
unsigned int chcr_offset;
u32 chcr_ie_bit;
};
#define to_sh_chan(chan) container_of(chan, struct sh_dmae_chan, common)
#define to_sh_desc(lh) container_of(lh, struct sh_desc, node)
#define tx_to_sh_desc(tx) container_of(tx, struct sh_desc, async_tx)
#define to_sh_dev(chan) container_of(chan->common.device,\
struct sh_dmae_device, common)
#endif /* __DMA_SHDMA_H */