c10cf1189d
The function dma_set_mask() tests internally whether the dma_mask pointer for the device is initialized and fails if the dma_mask pointer is NULL. On pci platforms, the device dma_mask pointer is initialized, when pci devices are enumerated, to point to the pci_dev->dma_mask which is 0xffffffff. However, for non-pci platforms, the dma_mask pointer may not be initialized and in that case dma_set_mask() will fail. This patch initializes the dma_mask and the coherent_dma_mask to 32bits in xhci_plat_probe(), before the call to usb_create_hcd() that sets the "uses_dma" flag for the usb bus and the call to usb_add_hcd() that creates coherent dma pools for the usb hcd. Moreover, a call to dma_set_mask() does not set the device coherent_dma_mask. Since the xhci-hcd driver calls dma_alloc_coherent() and dma_pool_alloc() to allocate consistent DMA memory blocks, the coherent DMA address mask has to be set explicitly. This patch sets the coherent_dma_mask to 64bits in xhci_gen_setup() when the xHC is capable for 64-bit DMA addressing. If dma_set_mask() succeeds, for a given bitmask, it is guaranteed that the given bitmask is also supported for consistent DMA mappings. Other changes introduced in this patch are: - The return value of dma_set_mask() is checked to ensure that the required dma bitmask conforms with the host system's addressing capabilities. - The dma_mask setup code for the non-primary hcd was removed since both primary and non-primary hcd refer to the same generic device whose dma_mask and coherent_dma_mask are already set during the setup of the primary hcd. - The code for reading the HCCPARAMS register to find out the addressing capabilities of xHC was removed since its value is already cached in xhci->hccparams. - hcd->self.controller was replaced with the dev variable since it is already available. Signed-off-by: Xenia Ragiadakou <burzalodowa@gmail.com> Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com> |
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| chipidea | ||
| class | ||
| core | ||
| dwc3 | ||
| early | ||
| gadget | ||
| host | ||
| image | ||
| misc | ||
| mon | ||
| musb | ||
| phy | ||
| renesas_usbhs | ||
| serial | ||
| storage | ||
| wusbcore | ||
| Kconfig | ||
| Makefile | ||
| README | ||
| usb-common.c | ||
| usb-skeleton.c | ||
To understand all the Linux-USB framework, you'll use these resources:
* This source code. This is necessarily an evolving work, and
includes kerneldoc that should help you get a current overview.
("make pdfdocs", and then look at "usb.pdf" for host side and
"gadget.pdf" for peripheral side.) Also, Documentation/usb has
more information.
* The USB 2.0 specification (from www.usb.org), with supplements
such as those for USB OTG and the various device classes.
The USB specification has a good overview chapter, and USB
peripherals conform to the widely known "Chapter 9".
* Chip specifications for USB controllers. Examples include
host controllers (on PCs, servers, and more); peripheral
controllers (in devices with Linux firmware, like printers or
cell phones); and hard-wired peripherals like Ethernet adapters.
* Specifications for other protocols implemented by USB peripheral
functions. Some are vendor-specific; others are vendor-neutral
but just standardized outside of the www.usb.org team.
Here is a list of what each subdirectory here is, and what is contained in
them.
core/ - This is for the core USB host code, including the
usbfs files and the hub class driver ("khubd").
host/ - This is for USB host controller drivers. This
includes UHCI, OHCI, EHCI, and others that might
be used with more specialized "embedded" systems.
gadget/ - This is for USB peripheral controller drivers and
the various gadget drivers which talk to them.
Individual USB driver directories. A new driver should be added to the
first subdirectory in the list below that it fits into.
image/ - This is for still image drivers, like scanners or
digital cameras.
../input/ - This is for any driver that uses the input subsystem,
like keyboard, mice, touchscreens, tablets, etc.
../media/ - This is for multimedia drivers, like video cameras,
radios, and any other drivers that talk to the v4l
subsystem.
../net/ - This is for network drivers.
serial/ - This is for USB to serial drivers.
storage/ - This is for USB mass-storage drivers.
class/ - This is for all USB device drivers that do not fit
into any of the above categories, and work for a range
of USB Class specified devices.
misc/ - This is for all USB device drivers that do not fit
into any of the above categories.