lwn.git/drivers/usb/dwc3/gadget.c, branch standardize-docs

Merge tag 'usb-for-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/balbi/usb into usb-testing

2017-06-20T03:39:34+00:00

Felipe writes: usb: changes for v4.13 merge window This time around we have a total of 57 non-merge commits. A list of most important changes follows: - Improvements to dwc3 tracing interface - Initial dual-role support for dwc3 - Improvements to how we handle DMA resources in dwc3 - A new f_uac1 implementation which much more flexible - Removal of AVR32 bits - Improvements to f_mass_storage driver

usb: dwc3: gadget: increase readability of dwc3_gadget_init_endpoints()

2017-06-13T10:21:08+00:00

The commit 47d3946ea220 usb: dwc3: refactor gadget endpoint count calculation refactored dwc3_gadget_init_endpoints() and in particular changed in or out endpoint numbering to be through. It's not always convenient and makes code a slightly harder to read. Introduce a new temporary variable to make it easier to understand what is going on inside the function. While doing that, rename local variables as follows: u8 num -> u8 total int num -> int kbytes Replace implicit direction check via epnum with explicit use of direction variable. While here, replace %d to %u when compounding endpoint name since we are using unsigned type. Signed-off-by: Andy Shevchenko Signed-off-by: Felipe Balbi

usb: dwc3: gadget: implement ->udc_set_speed()

2017-06-13T10:21:03+00:00

Use this method to make sure we don't try to connect on speeds not supported by the gadget driver. Signed-off-by: Felipe Balbi

usb: dwc3: gadget: slight cleanup to dwc3_process_event_entry()

2017-06-02T08:22:28+00:00

No functional changes, just a slight readability improvement. Signed-off-by: Felipe Balbi

usb: dwc3: update documentation

2017-06-02T08:22:27+00:00

No functional changes, just making sure we can use these for ReST docs later. Signed-off-by: Felipe Balbi

usb: dwc3: replace %p with %pK

2017-06-02T08:22:10+00:00

%p will leak kernel pointers, so let's not expose the information on dmesg and instead use %pK. %pK will only show the actual addresses if explicitly enabled under /proc/sys/kernel/kptr_restrict. Cc: Acked-by: Greg Kroah-Hartman Signed-off-by: Felipe Balbi

usb: dwc3: gadget: lazily map requests for DMA

2017-05-17T10:21:14+00:00

Some functions might want to have very, very long request queues. We can't make any assumptions about how many requests we *are* able to map, so instead of mapping requests early, let's map them late. This way, functions can queue as many requests as they'd like but we won't take DMA resources until they are needed. Also, we can now stop processing requests when we run out of DMA resources but still keep requests in the queue for late processing. Signed-off-by: Felipe Balbi

usb: dwc3: gadget: don't WARN about lack of TRBs

2017-05-17T10:20:51+00:00

We don't need a big fat warning with stack dump at all. Running out of TRBs is a normal condition and we will have more TRBs available as soon as some transfers complete. Signed-off-by: Felipe Balbi

usb: dwc3: gadget: Prevent losing events in event cache

2017-05-16T11:11:03+00:00

The dwc3 driver can overwite its previous events if its top-half IRQ handler (TH) gets invoked again before processing the events in the cache. We see this as a hang in the file transfer and the host will attempt to reset the device. TH gets the event count and deasserts the interrupt line by writing DWC3_GEVNTSIZ_INTMASK to DWC3_GEVNTSIZ. If there's a new event coming between reading the event count and interrupt deassertion, dwc3 will lose previous pending events. More generally, we will see 0 event count, which should not affect anything. This shouldn't be possible in the current dwc3 implementation. However, through testing and reading the PCIe trace, the TH occasionally still gets invoked one more time after HW interrupt deassertion. (With PCIe legacy interrupts, TH is called repeatedly as long as the interrupt line is asserted). We suspect that there is a small detection delay in the SW. To avoid this issue, Check DWC3_EVENT_PENDING flag to determine if the events are processed in the bottom-half IRQ handler. If not, return IRQ_HANDLED and don't process new event. Cc: stable@vger.kernel.org Signed-off-by: Thinh Nguyen Signed-off-by: Felipe Balbi

usb: dwc3: gadget: Fix ISO transfer performance

2017-05-16T11:11:03+00:00

Commit 08a36b543803 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()") caused a small change in the way ISO transfer is handled in the case when XferInProgress event happens on Isoc EP with an active transfer. This caused a performance degradation of 50%. e.g. using g_webcam on DUT and luvcview on host the video frame rate dropped from 16fps to 8fps @high-speed. Make the ISO transfer handling equivalent to that prior to that commit to get back the original ISO performance numbers. Fixes: 08a36b543803 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()") Signed-off-by: Roger Quadros Signed-off-by: Felipe Balbi