diff options
| author | Christoph Hellwig <hch@lst.de> | 2019-08-16 09:24:32 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-08-21 20:03:35 +0300 |
| commit | 7b81cb6bddd2c4f2489506771070924bd0ae9902 (patch) | |
| tree | e93409bd98a306bc26cc19c1c6a29f70029d42a0 /drivers/usb/isp1760 | |
| parent | 0709831a50d31b3caf2237e8d7fe89e15b0d919d (diff) | |
| download | linux-7b81cb6bddd2c4f2489506771070924bd0ae9902.tar.xz | |
usb: add a HCD_DMA flag instead of guestimating DMA capabilities
The usb core is the only major place in the kernel that checks for
a non-NULL device dma_mask to see if a device is DMA capable. This
is generally a bad idea, as all major busses always set up a DMA mask,
even if the device is not DMA capable - in fact bus layers like PCI
can't even know if a device is DMA capable at enumeration time. This
leads to lots of workaround in HCD drivers, and also prevented us from
setting up a DMA mask for platform devices by default last time we
tried.
Replace this guess with an explicit HCD_DMA that is set by drivers that
appear to have DMA support.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20190816062435.881-4-hch@lst.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/isp1760')
| -rw-r--r-- | drivers/usb/isp1760/isp1760-core.c | 3 | ||||
| -rw-r--r-- | drivers/usb/isp1760/isp1760-if.c | 1 |
2 files changed, 0 insertions, 4 deletions
diff --git a/drivers/usb/isp1760/isp1760-core.c b/drivers/usb/isp1760/isp1760-core.c index 55b94fd10331..fdeb4cf97cc5 100644 --- a/drivers/usb/isp1760/isp1760-core.c +++ b/drivers/usb/isp1760/isp1760-core.c @@ -120,9 +120,6 @@ int isp1760_register(struct resource *mem, int irq, unsigned long irqflags, (!IS_ENABLED(CONFIG_USB_ISP1761_UDC) || udc_disabled)) return -ENODEV; - /* prevent usb-core allocating DMA pages */ - dev->dma_mask = NULL; - isp = devm_kzalloc(dev, sizeof(*isp), GFP_KERNEL); if (!isp) return -ENOMEM; diff --git a/drivers/usb/isp1760/isp1760-if.c b/drivers/usb/isp1760/isp1760-if.c index 241a00d75027..07cc82ff327c 100644 --- a/drivers/usb/isp1760/isp1760-if.c +++ b/drivers/usb/isp1760/isp1760-if.c @@ -139,7 +139,6 @@ static int isp1761_pci_probe(struct pci_dev *dev, pci_set_master(dev); - dev->dev.dma_mask = NULL; ret = isp1760_register(&dev->resource[3], dev->irq, 0, &dev->dev, devflags); if (ret < 0) |