diff options
| author | Tze Yee Ng <tze.yee.ng@altera.com> | 2026-05-25 10:10:22 +0300 |
|---|---|---|
| committer | Vinod Koul <vkoul@kernel.org> | 2026-06-11 08:28:42 +0300 |
| commit | df0c2dc68770cf43f15df40b184df030b850ea05 (patch) | |
| tree | 3262cb5a9a9a556a6814000108ab8ec4aefa8682 | |
| parent | dc6d681e1571c89cd38145926fb2513d70a633e1 (diff) | |
| download | linux-df0c2dc68770cf43f15df40b184df030b850ea05.tar.xz | |
dmaengine: dw-axi-dmac: fix PM for system sleep and channel alloc
The driver only had runtime PM callbacks. If a channel stayed allocated
across system suspend/resume, the runtime usage count could remain
non-zero while hardware state (DMAC_CFG, clocks) was lost, and
axi_dma_runtime_resume() would not run to restore it.
Add system-sleep PM ops that use pm_runtime_force_suspend() and
pm_runtime_force_resume() so suspend/resume reuses the existing
axi_dma_suspend() and axi_dma_resume() paths.
Replace pm_runtime_get() with pm_runtime_resume_and_get() in
dma_chan_alloc_chan_resources() so clocks are enabled before a client
can immediately submit a transfer and touch MMIO.
Signed-off-by: Tze Yee Ng <tze.yee.ng@altera.com>
Link: https://patch.msgid.link/18bf778a3a1cc2f377ef8eb0d1508d8ac6371896.1779688569.git.tze.yee.ng@altera.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
| -rw-r--r-- | drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c index f7a50f470461..bcefaff03b5c 100644 --- a/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c +++ b/drivers/dma/dw-axi-dmac/dw-axi-dmac-platform.c @@ -516,11 +516,17 @@ static void dw_axi_dma_synchronize(struct dma_chan *dchan) static int dma_chan_alloc_chan_resources(struct dma_chan *dchan) { struct axi_dma_chan *chan = dchan_to_axi_dma_chan(dchan); + int ret; + + ret = pm_runtime_resume_and_get(chan->chip->dev); + if (ret < 0) + return ret; /* ASSERT: channel is idle */ if (axi_chan_is_hw_enable(chan)) { dev_err(chan2dev(chan), "%s is non-idle!\n", axi_chan_name(chan)); + pm_runtime_put(chan->chip->dev); return -EBUSY; } @@ -531,12 +537,11 @@ static int dma_chan_alloc_chan_resources(struct dma_chan *dchan) 64, 0); if (!chan->desc_pool) { dev_err(chan2dev(chan), "No memory for descriptors\n"); + pm_runtime_put(chan->chip->dev); return -ENOMEM; } dev_vdbg(dchan2dev(dchan), "%s: allocating\n", axi_chan_name(chan)); - pm_runtime_get(chan->chip->dev); - return 0; } @@ -1663,6 +1668,8 @@ static void dw_remove(struct platform_device *pdev) } static const struct dev_pm_ops dw_axi_dma_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) SET_RUNTIME_PM_OPS(axi_dma_runtime_suspend, axi_dma_runtime_resume, NULL) }; |