diff options
author | Linus Walleij <linus.walleij@stericsson.com> | 2010-03-27 02:44:01 +0300 |
---|---|---|
committer | Dan Williams <dan.j.williams@intel.com> | 2010-03-27 02:44:01 +0300 |
commit | c3635c78e500a52c9fcd55de381a72928d9e054d (patch) | |
tree | 87403f402227cd8b5572550e70facf81c9eaa0d9 /drivers/dma/coh901318.c | |
parent | 0f65169b1bf44220308e1ce1f6666ad03ddc27af (diff) | |
download | linux-c3635c78e500a52c9fcd55de381a72928d9e054d.tar.xz |
DMAENGINE: generic slave control v2
Convert the device_terminate_all() operation on the
DMA engine to a generic device_control() operation
which can now optionally support also pausing and
resuming DMA on a certain channel. Implemented for the
COH 901 318 DMAC as an example.
[dan.j.williams@intel.com: update for timberdale]
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Li Yang <leoli@freescale.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Cc: Magnus Damm <damm@opensource.se>
Cc: Liam Girdwood <lrg@slimlogic.co.uk>
Cc: Joe Perches <joe@perches.com>
Cc: Roland Dreier <rdreier@cisco.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma/coh901318.c')
-rw-r--r-- | drivers/dma/coh901318.c | 42 |
1 files changed, 28 insertions, 14 deletions
diff --git a/drivers/dma/coh901318.c b/drivers/dma/coh901318.c index f636c4a87c7f..53c54e034aa3 100644 --- a/drivers/dma/coh901318.c +++ b/drivers/dma/coh901318.c @@ -506,10 +506,11 @@ u32 coh901318_get_bytes_left(struct dma_chan *chan) EXPORT_SYMBOL(coh901318_get_bytes_left); -/* Stops a transfer without losing data. Enables power save. - Use this function in conjunction with coh901318_continue(..) -*/ -void coh901318_stop(struct dma_chan *chan) +/* + * Pauses a transfer without losing data. Enables power save. + * Use this function in conjunction with coh901318_resume. + */ +static void coh901318_pause(struct dma_chan *chan) { u32 val; unsigned long flags; @@ -550,12 +551,11 @@ void coh901318_stop(struct dma_chan *chan) spin_unlock_irqrestore(&cohc->lock, flags); } -EXPORT_SYMBOL(coh901318_stop); -/* Continues a transfer that has been stopped via 300_dma_stop(..). +/* Resumes a transfer that has been stopped via 300_dma_stop(..). Power save is handled. */ -void coh901318_continue(struct dma_chan *chan) +static void coh901318_resume(struct dma_chan *chan) { u32 val; unsigned long flags; @@ -581,7 +581,6 @@ void coh901318_continue(struct dma_chan *chan) spin_unlock_irqrestore(&cohc->lock, flags); } -EXPORT_SYMBOL(coh901318_continue); bool coh901318_filter_id(struct dma_chan *chan, void *chan_id) { @@ -945,7 +944,7 @@ coh901318_free_chan_resources(struct dma_chan *chan) spin_unlock_irqrestore(&cohc->lock, flags); - chan->device->device_terminate_all(chan); + chan->device->device_control(chan, DMA_TERMINATE_ALL); } @@ -1179,16 +1178,29 @@ coh901318_issue_pending(struct dma_chan *chan) spin_unlock_irqrestore(&cohc->lock, flags); } -static void -coh901318_terminate_all(struct dma_chan *chan) +static int +coh901318_control(struct dma_chan *chan, enum dma_ctrl_cmd cmd) { unsigned long flags; struct coh901318_chan *cohc = to_coh901318_chan(chan); struct coh901318_desc *cohd; void __iomem *virtbase = cohc->base->virtbase; - coh901318_stop(chan); + if (cmd == DMA_PAUSE) { + coh901318_pause(chan); + return 0; + } + + if (cmd == DMA_RESUME) { + coh901318_resume(chan); + return 0; + } + + if (cmd != DMA_TERMINATE_ALL) + return -ENXIO; + /* The remainder of this function terminates the transfer */ + coh901318_pause(chan); spin_lock_irqsave(&cohc->lock, flags); /* Clear any pending BE or TC interrupt */ @@ -1227,6 +1239,8 @@ coh901318_terminate_all(struct dma_chan *chan) cohc->busy = 0; spin_unlock_irqrestore(&cohc->lock, flags); + + return 0; } void coh901318_base_init(struct dma_device *dma, const int *pick_chans, struct coh901318_base *base) @@ -1344,7 +1358,7 @@ static int __init coh901318_probe(struct platform_device *pdev) base->dma_slave.device_prep_slave_sg = coh901318_prep_slave_sg; base->dma_slave.device_is_tx_complete = coh901318_is_tx_complete; base->dma_slave.device_issue_pending = coh901318_issue_pending; - base->dma_slave.device_terminate_all = coh901318_terminate_all; + base->dma_slave.device_control = coh901318_control; base->dma_slave.dev = &pdev->dev; err = dma_async_device_register(&base->dma_slave); @@ -1364,7 +1378,7 @@ static int __init coh901318_probe(struct platform_device *pdev) base->dma_memcpy.device_prep_dma_memcpy = coh901318_prep_memcpy; base->dma_memcpy.device_is_tx_complete = coh901318_is_tx_complete; base->dma_memcpy.device_issue_pending = coh901318_issue_pending; - base->dma_memcpy.device_terminate_all = coh901318_terminate_all; + base->dma_memcpy.device_control = coh901318_control; base->dma_memcpy.dev = &pdev->dev; /* * This controller can only access address at even 32bit boundaries, |