diff options
| author | Hongbo Zhang <hongbo.zhang@freescale.com> | 2014-05-21 16:03:02 +0800 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2014-07-14 21:32:18 +0530 |
| commit | 14c6a3333c8e885604fc98768d8b9a32e08110ac (patch) | |
| tree | 5dae60ced4af6ade4439b656730d05e09c8ae393 /drivers/dma/fsldma.c | |
| parent | 2baff5700b0832632f05c2ae93362fe3320cc735 (diff) | |
| download | linux-14c6a3333c8e885604fc98768d8b9a32e08110ac.tar.gz | |
dmaengine: Freescale: add suspend resume functions for DMA driver
This patch adds suspend and resume functions for Freescale DMA driver. Signed-off-by: Hongbo Zhang <hongbo.zhang@freescale.com> Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma/fsldma.c')
| -rw-r--r-- | drivers/dma/fsldma.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/drivers/dma/fsldma.c b/drivers/dma/fsldma.c index b291e6c65053..465f16dd78e5 100644 --- a/drivers/dma/fsldma.c +++ b/drivers/dma/fsldma.c @@ -400,6 +400,14 @@ static dma_cookie_t fsl_dma_tx_submit(struct dma_async_tx_descriptor *tx) spin_lock_bh(&chan->desc_lock); +#ifdef CONFIG_PM + if (unlikely(chan->pm_state != RUNNING)) { + chan_dbg(chan, "cannot submit due to suspend\n"); + spin_unlock_bh(&chan->desc_lock); + return -1; + } +#endif + /* * assign cookies to all of the software descriptors * that make up this transaction @@ -1221,6 +1229,9 @@ static int fsl_dma_chan_probe(struct fsldma_device *fdev, INIT_LIST_HEAD(&chan->ld_pending); INIT_LIST_HEAD(&chan->ld_running); chan->idle = true; +#ifdef CONFIG_PM + chan->pm_state = RUNNING; +#endif chan->common.device = &fdev->common; dma_cookie_init(&chan->common); @@ -1360,6 +1371,69 @@ static int fsldma_of_remove(struct platform_device *op) return 0; } +#ifdef CONFIG_PM +static int fsldma_suspend_late(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct fsldma_device *fdev = platform_get_drvdata(pdev); + struct fsldma_chan *chan; + int i; + + for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { + chan = fdev->chan[i]; + if (!chan) + continue; + + spin_lock_bh(&chan->desc_lock); + if (unlikely(!chan->idle)) + goto out; + chan->regs_save.mr = get_mr(chan); + chan->pm_state = SUSPENDED; + spin_unlock_bh(&chan->desc_lock); + } + return 0; + +out: + for (; i >= 0; i--) { + chan = fdev->chan[i]; + if (!chan) + continue; + chan->pm_state = RUNNING; + spin_unlock_bh(&chan->desc_lock); + } + return -EBUSY; +} + +static int fsldma_resume_early(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct fsldma_device *fdev = platform_get_drvdata(pdev); + struct fsldma_chan *chan; + u32 mode; + int i; + + for (i = 0; i < FSL_DMA_MAX_CHANS_PER_DEVICE; i++) { + chan = fdev->chan[i]; + if (!chan) + continue; + + spin_lock_bh(&chan->desc_lock); + mode = chan->regs_save.mr + & ~FSL_DMA_MR_CS & ~FSL_DMA_MR_CC & ~FSL_DMA_MR_CA; + set_mr(chan, mode); + chan->pm_state = RUNNING; + spin_unlock_bh(&chan->desc_lock); + } + + return 0; +} + +static const struct dev_pm_ops fsldma_pm_ops = { + .suspend_late = fsldma_suspend_late, + .resume_early = fsldma_resume_early, +}; +#endif + static const struct of_device_id fsldma_of_ids[] = { { .compatible = "fsl,elo3-dma", }, { .compatible = "fsl,eloplus-dma", }, @@ -1372,6 +1446,9 @@ static struct platform_driver fsldma_of_driver = { .name = "fsl-elo-dma", .owner = THIS_MODULE, .of_match_table = fsldma_of_ids, +#ifdef CONFIG_PM + .pm = &fsldma_pm_ops, +#endif }, .probe = fsldma_of_probe, .remove = fsldma_of_remove, |