lkml.org 
[lkml]   [2018]   [Aug]   [29]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 1/3] driver core: initialize a default DMA mask for platform device
Date
We still treat devices without a DMA mask as defaulting to 32-bits for
both mask, but a few releases ago we've started warning about such
cases, as they require special cases to work around this sloppyness.
Add a dma_mask field to struct platform_object so that we can initialize
the dma_mask pointer in struct device and initialize both masks to
32-bits by default. Architectures can still override this in
arch_setup_pdev_archdata if needed.

Note that the code looks a little odd with the various conditionals
because we have to support platform_device structures that are
statically allocated.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/base/platform.c | 15 +++++++++++++--
include/linux/platform_device.h | 1 +
2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index dff82a3c2caa..baf4b06cf2d9 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -225,6 +225,17 @@ struct platform_object {
char name[];
};

+static void setup_pdev_archdata(struct platform_device *pdev)
+{
+ if (!pdev->dev.coherent_dma_mask)
+ pdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
+ if (!pdev->dma_mask)
+ pdev->dma_mask = DMA_BIT_MASK(32);
+ if (!pdev->dev.dma_mask)
+ pdev->dev.dma_mask = &pdev->dma_mask;
+ arch_setup_pdev_archdata(pdev);
+};
+
/**
* platform_device_put - destroy a platform device
* @pdev: platform device to free
@@ -271,7 +282,7 @@ struct platform_device *platform_device_alloc(const char *name, int id)
pa->pdev.id = id;
device_initialize(&pa->pdev.dev);
pa->pdev.dev.release = platform_device_release;
- arch_setup_pdev_archdata(&pa->pdev);
+ setup_pdev_archdata(&pa->pdev);
}

return pa ? &pa->pdev : NULL;
@@ -472,7 +483,7 @@ EXPORT_SYMBOL_GPL(platform_device_del);
int platform_device_register(struct platform_device *pdev)
{
device_initialize(&pdev->dev);
- arch_setup_pdev_archdata(pdev);
+ setup_pdev_archdata(pdev);
return platform_device_add(pdev);
}
EXPORT_SYMBOL_GPL(platform_device_register);
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 1a9f38f27f65..d9dc4883d5fb 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -25,6 +25,7 @@ struct platform_device {
int id;
bool id_auto;
struct device dev;
+ u64 dma_mask;
u32 num_resources;
struct resource *resource;

--
2.18.0
\
 
 \ /
  Last update: 2018-08-29 08:25    [W:0.070 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site