From 7b81cb6bddd2c4f2489506771070924bd0ae9902 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 16 Aug 2019 08:24:32 +0200 Subject: 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 Link: https://lore.kernel.org/r/20190816062435.881-4-hch@lst.de Signed-off-by: Greg Kroah-Hartman --- drivers/usb/dwc2/hcd.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/usb/dwc2') diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c index 111787a137ee..81afe553aa66 100644 --- a/drivers/usb/dwc2/hcd.c +++ b/drivers/usb/dwc2/hcd.c @@ -5062,13 +5062,13 @@ int dwc2_hcd_init(struct dwc2_hsotg *hsotg) dwc2_hc_driver.reset_device = dwc2_reset_device; } + if (hsotg->params.host_dma) + dwc2_hc_driver.flags |= HCD_DMA; + hcd = usb_create_hcd(&dwc2_hc_driver, hsotg->dev, dev_name(hsotg->dev)); if (!hcd) goto error1; - if (!hsotg->params.host_dma) - hcd->self.uses_dma = 0; - hcd->has_tt = 1; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); -- cgit v1.2.3