[PATCH 4.4 124/183] dmaengine: dw: platform: Switch to acpi_dma_controller_register()

From: Greg Kroah-Hartman
Date: Tue Jan 28 2020 - 09:12:13 EST


From: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

[ Upstream commit e7b8514e4d68bec21fc6385fa0a66797ddc34ac9 ]

There is a possibility to have registered ACPI DMA controller
while it has been gone already.

To avoid the potential crash, move to non-managed
acpi_dma_controller_register().

Fixes: 42c91ee71d6d ("dw_dmac: add ACPI support")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20190820131546.75744-8-andriy.shevchenko@xxxxxxxxxxxxxxx
Signed-off-by: Vinod Koul <vkoul@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/dma/dw/platform.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/dma/dw/platform.c b/drivers/dma/dw/platform.c
index 68a4815750b51..22d0cc1855b5f 100644
--- a/drivers/dma/dw/platform.c
+++ b/drivers/dma/dw/platform.c
@@ -87,13 +87,20 @@ static void dw_dma_acpi_controller_register(struct dw_dma *dw)
dma_cap_set(DMA_SLAVE, info->dma_cap);
info->filter_fn = dw_dma_acpi_filter;

- ret = devm_acpi_dma_controller_register(dev, acpi_dma_simple_xlate,
- info);
+ ret = acpi_dma_controller_register(dev, acpi_dma_simple_xlate, info);
if (ret)
dev_err(dev, "could not register acpi_dma_controller\n");
}
+
+static void dw_dma_acpi_controller_free(struct dw_dma *dw)
+{
+ struct device *dev = dw->dma.dev;
+
+ acpi_dma_controller_free(dev);
+}
#else /* !CONFIG_ACPI */
static inline void dw_dma_acpi_controller_register(struct dw_dma *dw) {}
+static inline void dw_dma_acpi_controller_free(struct dw_dma *dw) {}
#endif /* !CONFIG_ACPI */

#ifdef CONFIG_OF
@@ -225,6 +232,9 @@ static int dw_remove(struct platform_device *pdev)
{
struct dw_dma_chip *chip = platform_get_drvdata(pdev);

+ if (ACPI_HANDLE(&pdev->dev))
+ dw_dma_acpi_controller_free(chip->dw);
+
if (pdev->dev.of_node)
of_dma_controller_free(pdev->dev.of_node);

--
2.20.1