8ceafbfa91
Pull DMA mask updates from Russell King: "This series cleans up the handling of DMA masks in a lot of drivers, fixing some bugs as we go. Some of the more serious errors include: - drivers which only set their coherent DMA mask if the attempt to set the streaming mask fails. - drivers which test for a NULL dma mask pointer, and then set the dma mask pointer to a location in their module .data section - which will cause problems if the module is reloaded. To counter these, I have introduced two helper functions: - dma_set_mask_and_coherent() takes care of setting both the streaming and coherent masks at the same time, with the correct error handling as specified by the API. - dma_coerce_mask_and_coherent() which resolves the problem of drivers forcefully setting DMA masks. This is more a marker for future work to further clean these locations up - the code which creates the devices really should be initialising these, but to fix that in one go along with this change could potentially be very disruptive. The last thing this series does is prise away some of Linux's addition to "DMA addresses are physical addresses and RAM always starts at zero". We have ARM LPAE systems where all system memory is above 4GB physical, hence having DMA masks interpreted by (eg) the block layers as describing physical addresses in the range 0..DMAMASK fails on these platforms. Santosh Shilimkar addresses this in this series; the patches were copied to the appropriate people multiple times but were ignored. Fixing this also gets rid of some ARM weirdness in the setup of the max*pfn variables, and brings ARM into line with every other Linux architecture as far as those go" * 'for-linus-dma-masks' of git://git.linaro.org/people/rmk/linux-arm: (52 commits) ARM: 7805/1: mm: change max*pfn to include the physical offset of memory ARM: 7797/1: mmc: Use dma_max_pfn(dev) helper for bounce_limit calculations ARM: 7796/1: scsi: Use dma_max_pfn(dev) helper for bounce_limit calculations ARM: 7795/1: mm: dma-mapping: Add dma_max_pfn(dev) helper function ARM: 7794/1: block: Rename parameter dma_mask to max_addr for blk_queue_bounce_limit() ARM: DMA-API: better handing of DMA masks for coherent allocations ARM: 7857/1: dma: imx-sdma: setup dma mask DMA-API: firmware/google/gsmi.c: avoid direct access to DMA masks DMA-API: dcdbas: update DMA mask handing DMA-API: dma: edma.c: no need to explicitly initialize DMA masks DMA-API: usb: musb: use platform_device_register_full() to avoid directly messing with dma masks DMA-API: crypto: remove last references to 'static struct device *dev' DMA-API: crypto: fix ixp4xx crypto platform device support DMA-API: others: use dma_set_coherent_mask() DMA-API: staging: use dma_set_coherent_mask() DMA-API: usb: use new dma_coerce_mask_and_coherent() DMA-API: usb: use dma_set_coherent_mask() DMA-API: parport: parport_pc.c: use dma_coerce_mask_and_coherent() DMA-API: net: octeon: use dma_coerce_mask_and_coherent() DMA-API: net: nxp/lpc_eth: use dma_coerce_mask_and_coherent() ... |
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atm | ||
c67x00 | ||
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.