 7a1cd9ad87
			
		
	
	
	7a1cd9ad87
	
	
	
		
			
			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>
		
			
				
	
	
		
			67 lines
		
	
	
	
		
			2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			67 lines
		
	
	
	
		
			2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Renesas SuperH DMA Engine support
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|  *
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|  * Copyright (C) 2009 Nobuhiro Iwamatsu <iwamatsu.nobuhiro@renesas.com>
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|  * Copyright (C) 2009 Renesas Solutions, Inc. All rights reserved.
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|  *
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|  * This is free software; you can redistribute it and/or modify
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|  * it under the terms of the GNU General Public License as published by
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|  * the Free Software Foundation; either version 2 of the License, or
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|  * (at your option) any later version.
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|  *
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|  */
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| #ifndef __DMA_SHDMA_H
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| #define __DMA_SHDMA_H
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| 
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| #include <linux/dmaengine.h>
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| #include <linux/interrupt.h>
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| #include <linux/list.h>
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| 
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| #define SH_DMAC_MAX_CHANNELS 20
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| #define SH_DMA_SLAVE_NUMBER 256
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| #define SH_DMA_TCR_MAX 0x00FFFFFF	/* 16MB */
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| 
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| struct device;
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| 
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| enum dmae_pm_state {
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| 	DMAE_PM_ESTABLISHED,
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| 	DMAE_PM_BUSY,
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| 	DMAE_PM_PENDING,
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| };
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| 
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| struct sh_dmae_chan {
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| 	dma_cookie_t completed_cookie;	/* The maximum cookie completed */
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| 	spinlock_t desc_lock;		/* Descriptor operation lock */
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| 	struct list_head ld_queue;	/* Link descriptors queue */
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| 	struct list_head ld_free;	/* Link descriptors free */
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| 	struct dma_chan common;		/* DMA common channel */
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| 	struct device *dev;		/* Channel device */
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| 	struct tasklet_struct tasklet;	/* Tasklet */
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| 	int descs_allocated;		/* desc count */
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| 	int xmit_shift;			/* log_2(bytes_per_xfer) */
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| 	int irq;
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| 	int id;				/* Raw id of this channel */
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| 	u32 __iomem *base;
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| 	char dev_id[16];		/* unique name per DMAC of channel */
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| 	int pm_error;
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| 	enum dmae_pm_state pm_state;
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| };
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| 
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| struct sh_dmae_device {
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| 	struct dma_device common;
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| 	struct sh_dmae_chan *chan[SH_DMAC_MAX_CHANNELS];
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| 	struct sh_dmae_pdata *pdata;
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| 	struct list_head node;
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| 	u32 __iomem *chan_reg;
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| 	u16 __iomem *dmars;
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| 	unsigned int chcr_offset;
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| 	u32 chcr_ie_bit;
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| };
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| 
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| #define to_sh_chan(chan) container_of(chan, struct sh_dmae_chan, common)
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| #define to_sh_desc(lh) container_of(lh, struct sh_desc, node)
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| #define tx_to_sh_desc(tx) container_of(tx, struct sh_desc, async_tx)
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| #define to_sh_dev(chan) container_of(chan->common.device,\
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| 				     struct sh_dmae_device, common)
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| 
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| #endif	/* __DMA_SHDMA_H */
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