Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 0196285e authored by H Hartley Sweeten's avatar H Hartley Sweeten Committed by Greg Kroah-Hartman
Browse files

staging: comedi: das16: introduce das16_isadma_program() 



Introduce a helper function to program the ISA DMA controller. Program
the ISA DMA as described in Documentation/DMA-ISA-LPC.txt.

Signed-off-by: default avatarH Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: default avatarIan Abbott <abbotti@mev.co.uk>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 59e561f3

drivers/staging/comedi/drivers/das16.c

+19 −16
Original line number Diff line number Diff line
@@ -461,6 +461,20 @@ struct das16_private_struct { 
	unsigned int		can_burst:1;

};



static void das16_isadma_program(unsigned int dma_chan,

				 struct das16_dma_desc *dma)

{

	unsigned long flags;



	flags = claim_dma_lock();

	clear_dma_ff(dma_chan);

	set_dma_mode(dma_chan, DMA_MODE_READ);

	set_dma_addr(dma_chan, dma->hw_addr);

	set_dma_count(dma_chan, dma->size);

	enable_dma(dma_chan);

	release_dma_lock(flags);

}



static void das16_ai_enable(struct comedi_device *dev,

			    unsigned int mode, unsigned int src)

{
@@ -547,6 +561,7 @@ static void das16_interrupt(struct comedi_device *dev) 
	dma_flags = claim_dma_lock();

	clear_dma_ff(devpriv->dma_chan);

	residue = disable_dma_on_even(dev);

	release_dma_lock(dma_flags);



	/*  figure out how many points to read */

	if (residue > dma->size) {
@@ -568,12 +583,9 @@ static void das16_interrupt(struct comedi_device *dev) 
	/* re-enable dma */

	if ((async->events & COMEDI_CB_EOA) == 0) {

		nxt_dma = &devpriv->dma_desc[devpriv->cur_dma];

		set_dma_addr(devpriv->dma_chan, nxt_dma->hw_addr);

		nxt_dma->size = DAS16_DMA_SIZE;

		set_dma_count(devpriv->dma_chan, nxt_dma->size);

		enable_dma(devpriv->dma_chan);

		das16_isadma_program(devpriv->dma_chan, nxt_dma);

	}

	release_dma_lock(dma_flags);



	spin_unlock_irqrestore(&dev->spinlock, spin_flags);
@@ -799,17 +811,9 @@ static int das16_cmd_exec(struct comedi_device *dev, struct comedi_subdevice *s) 
	outb(byte, dev->iobase + DAS16_PACER_REG);



	/* set up dma transfer */

	flags = claim_dma_lock();

	disable_dma(devpriv->dma_chan);

	/* clear flip-flop to make sure 2-byte registers for

	 * count and address get set correctly */

	clear_dma_ff(devpriv->dma_chan);

	devpriv->cur_dma = 0;

	set_dma_addr(devpriv->dma_chan, dma->hw_addr);

	dma->size = DAS16_DMA_SIZE;

	set_dma_count(devpriv->dma_chan, dma->size);

	enable_dma(devpriv->dma_chan);

	release_dma_lock(flags);

	das16_isadma_program(devpriv->dma_chan, dma);



	/*  set up timer */

	spin_lock_irqsave(&dev->spinlock, flags);
@@ -1018,7 +1022,6 @@ static int das16_alloc_dma(struct comedi_device *dev, unsigned int dma_chan) 


	flags = claim_dma_lock();

	disable_dma(devpriv->dma_chan);

	set_dma_mode(devpriv->dma_chan, DMA_MODE_READ);

	release_dma_lock(flags);



	init_timer(&devpriv->timer);