diff options
| author | Krzysztof Kozlowski <k.kozlowski@samsung.com> | 2014-11-18 12:17:56 +0100 |
|---|---|---|
| committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2014-11-27 16:13:08 +0000 |
| commit | b816ccc5c01fb7fe1fb001ff7aa5aa7e5a8aa76b (patch) | |
| tree | ab81c47bf870da01f8dbd4812b9a613c3ca48422 /drivers/dma | |
| parent | ae43b3289186480f81c78bb63d788a85a3631f47 (diff) | |
ARM: 8206/1: dmaengine: pl330: Add PM sleep support
Add system suspend/resume capabilities to the pl330 driver so the amba
bus clock could be also unprepared to conserve energy.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/pl330.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/dma/pl330.c b/drivers/dma/pl330.c index 39ea8d436b8..2d324f78071 100644 --- a/drivers/dma/pl330.c +++ b/drivers/dma/pl330.c @@ -2627,6 +2627,46 @@ static int pl330_dma_device_slave_caps(struct dma_chan *dchan, return 0; } +/* + * Runtime PM callbacks are provided by amba/bus.c driver. + * + * It is assumed here that IRQ safe runtime PM is chosen in probe and amba + * bus driver will only disable/enable the clock in runtime PM callbacks. + */ +static int __maybe_unused pl330_suspend(struct device *dev) +{ + struct amba_device *pcdev = to_amba_device(dev); + + pm_runtime_disable(dev); + + if (!pm_runtime_status_suspended(dev)) { + /* amba did not disable the clock */ + amba_pclk_disable(pcdev); + } + amba_pclk_unprepare(pcdev); + + return 0; +} + +static int __maybe_unused pl330_resume(struct device *dev) +{ + struct amba_device *pcdev = to_amba_device(dev); + int ret; + + ret = amba_pclk_prepare(pcdev); + if (ret) + return ret; + + if (!pm_runtime_status_suspended(dev)) + ret = amba_pclk_enable(pcdev); + + pm_runtime_enable(dev); + + return ret; +} + +static SIMPLE_DEV_PM_OPS(pl330_pm, pl330_suspend, pl330_resume); + static int pl330_probe(struct amba_device *adev, const struct amba_id *id) { @@ -2852,6 +2892,7 @@ static struct amba_driver pl330_driver = { .drv = { .owner = THIS_MODULE, .name = "dma-pl330", + .pm = &pl330_pm, }, .id_table = pl330_ids, .probe = pl330_probe, |