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[23.128.96.18]) by mx.google.com with ESMTP id c17si1728655ede.413.2021.06.22.15.03.28; Tue, 22 Jun 2021 15:03:52 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@mg.codeaurora.org header.s=smtp header.b=dGXVHIEm; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230415AbhFVWDg (ORCPT + 99 others); Tue, 22 Jun 2021 18:03:36 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:63410 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230114AbhFVWDf (ORCPT ); Tue, 22 Jun 2021 18:03:35 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1624399279; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=MR9MlBoXPnT7Gh3fnbLq2vyxHX7zu5zA9YGJjxcp/QY=; b=dGXVHIEmYemhvWEV/ezLB5OWbY8dLS8Ea/6KmjbNVvI7YT7wH8F+pDnLYSwoNrXKC9hVX7Zx W2yeDtCDMRcUsiHZ0w1wLKnA2l7blFw6SeYwBLYY+j240t9NFRWtx86l5qh7iNIEy+iHc3C4 QqqAfuRl2CZgtyPnlEnNzqC1Fzc= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-east-1.postgun.com with SMTP id 60d25d955e3e57240b13ffb6 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 22 Jun 2021 22:00:53 GMT Sender: wcheng=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 5A085C4360C; Tue, 22 Jun 2021 22:00:52 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-caf-mail-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.9 required=2.0 tests=ALL_TRUSTED,BAYES_00, NICE_REPLY_A,SPF_FAIL,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from [10.110.90.136] (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: wcheng) by smtp.codeaurora.org (Postfix) with ESMTPSA id BC78EC43143; Tue, 22 Jun 2021 22:00:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org BC78EC43143 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=wcheng@codeaurora.org Subject: Re: [PATCH v10 0/6] Re-introduce TX FIFO resize for larger EP bursting To: Ferry Toth , balbi@kernel.org, gregkh@linuxfoundation.org, robh+dt@kernel.org, agross@kernel.org, bjorn.andersson@linaro.org, frowand.list@gmail.com Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, jackp@codeaurora.org, heikki.krogerus@linux.intel.com, andy.shevchenko@gmail.com References: <1623923899-16759-1-git-send-email-wcheng@codeaurora.org> <2e01c435-9ecc-4e3b-f55c-612a86667020@codeaurora.org> <2ae9fa6a-3bb1-3742-0dd3-59678bdd8643@gmail.com> <4e5fbcdb-765a-895d-7723-a87feed6eed5@gmail.com> From: Wesley Cheng Message-ID: Date: Tue, 22 Jun 2021 15:00:46 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <4e5fbcdb-765a-895d-7723-a87feed6eed5@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 6/22/2021 1:09 PM, Ferry Toth wrote: > Hi > > Op 22-06-2021 om 20:38 schreef Wesley Cheng: >> >> On 6/19/2021 5:40 AM, Ferry Toth wrote: >>> Hi >>> >>> Op 18-06-2021 om 00:25 schreef Wesley Cheng: >>>> Hi, >>>> >>>> On 6/17/2021 2:55 PM, Ferry Toth wrote: >>>>> Hi >>>>> >>>>> Op 17-06-2021 om 23:48 schreef Wesley Cheng: >>>>>> Hi, >>>>>> >>>>>> On 6/17/2021 2:01 PM, Ferry Toth wrote: >>>>>>> Hi >>>>>>> >>>>>>> Op 17-06-2021 om 11:58 schreef Wesley Cheng: >>>>>>>> Changes in V10: >>>>>>>>     - Fixed compilation errors in config where OF is not used >>>>>>>> (error due to >>>>>>>>       unknown symbol for of_add_property()).  Add of_add_property() >>>>>>>> stub. >>>>>>>>     - Fixed compilation warning for incorrect argument being >>>>>>>> passed to >>>>>>>> dwc3_mdwidth >>>>>>> This fixes the OOPS I had in V9. I do not see any change in >>>>>>> performance >>>>>>> on Merrifield though. >>>>>> I see...thanks Ferry! With your testing, are you writing to the >>>>>> device's >>>>>> internal storage (ie UFS, eMMC, etc...), or did you use a ramdisk as >>>>>> well? >>>>> In this case I just tested the EEM path using iperf3. >>>>> >>>> Got it.  I don't believe f_eem will use a high enough (if at all) >>>> bMaxBurst value to change the TXFIFO size. >>>> >>>>>> If not with a ramdisk, we might want to give that a try to avoid the >>>>>> storage path being the bottleneck.  You can use "dd" to create an >>>>>> empty >>>>>> file, and then just use that as the LUN's backing file. >>>>>> >>>>>> echo ramdisk.img > >>>>>> /sys/kernel/config/usb_gadget/g1/functions/mass_storage.0/lun.0/file >>>>> Ah, why didn't I think of that. I have currently mass storage setup >>>>> with >>>>> eMMC but it seems that is indeed the bottleneck. >>>>> >>> I created a 64MB disk following the instructions here >>> http://www.linux-usb.org/gadget/file_storage.html (that seems a little >>> outdated, at least I can not start the first partition at sector 8, but >>> minimum 2048), and added a test file on it. >>> >>> I then copy the file to /dev/shm prior to setting configfs (composite >>> device gser/eem/mass_storage/uac2). >>> >>> journal shows: >>> >>> kernel: Mass Storage Function, version: 2009/09/11 >>> kernel: LUN: removable file: (no medium) >>> >>> I don't know what that means, because I see the test file on the >>> ramdisk. >>> >>> Then I again used gnome disks to benchmark (read/write 10MB): >>> >>> With V10 on top v5.13.0-rc5: >>> >>> R/W speed = 35.6/35.8MB/s, access time 0.35ms >>> >>> With no patches on top v5.12.0: >>> >>> R/W speed = 35.7/36.1MB/s, access time 0.35ms >> Hi Ferry, >> >>> I see no speed difference (and it's about the same as with the eMMC >>> backed disk). But the patches are causing a new call trace >>> >> Would you happen to know what DWC3 controller revision the device is >> using?  The callstack print occurs, because it looks like it ran out of >> internal memory, although there should be logic present for making sure >> that at least there is enough room for 1 FIFO per endpoint.  (possibly >> the logic/math depends on the controller revision) Hi Ferry, > > Do you know where I could find that in a file on the device? > Maybe you can just dump the DWC3 registers? cat /sys/kernel/debug/usb//regdump Was going to ask for the same to confirm the TXFIFO sizes from your results below :). > Otherwise, I'm hoping Andy will know? > >> >> Also, is there a way to use just a mass storage only composition?  Based >> on the above observation, that probably means that the mass storage >> interface wasn't resized at all, because the configuration took up a lot >> of the internal FIFO space. > > Sure, it's configured through configfs. With only mass_storage I have: > > With V10 on top v5.13.0-rc5: > > R/W speed = 41,6/39,3MB/s, access time 0.33ms > > With no patches on top v5.12.0: > > R/W speed = 41,1/38,7MB/s, access time 0.38ms > Thanks Ferry! Could you collect the regdump, so I can confirm the two things mentioned? Thanks Wesley Cheng >> Thanks >> Wesley Cheng >> >>> kernel: using random self ethernet address >>> kernel: using random host ethernet address >>> kernel: Mass Storage Function, version: 2009/09/11 >>> kernel: LUN: removable file: (no medium) >>> kernel: usb0: HOST MAC aa:bb:cc:dd:ee:f2 >>> kernel: usb0: MAC aa:bb:cc:dd:ee:f1 >>> kernel: IPv6: ADDRCONF(NETDEV_CHANGE): usb0: link becomes ready >>> kernel: dwc3 dwc3.0.auto: Fifosize(2154) > RAM size(2022) ep5in >>> depth:115540359 >>> kernel: ------------[ cut here ]------------ >>> kernel: WARNING: CPU: 0 PID: 594 at drivers/usb/gadget/udc/core.c:278 >>> usb_ep_queue+0x75/0x80 >>> kernel: Modules linked in: usb_f_uac2 u_audio usb_f_mass_storage >>> usb_f_eem u_ether usb_f_serial u_serial libcomposite rfcomm iptable_nat >>> bnep snd_sof_nocodec spi_pxa2> >>> kernel: CPU: 0 PID: 594 Comm: irq/14-dwc3 Not tainted >>> 5.13.0-rc5-edison-acpi-standard #1 >>> kernel: Hardware name: Intel Corporation Merrifield/BODEGA BAY, BIOS 542 >>> 2015.01.21:18.19.48 >>> kernel: RIP: 0010:usb_ep_queue+0x75/0x80 >>> kernel: Code: 01 73 e4 48 8b 05 fb 63 06 01 48 85 c0 74 12 48 8b 78 08 >>> 44 89 e9 4c 89 e2 48 89 ee e8 74 05 00 00 44 89 e8 5d 41 5c 41 5d c3 >>> <0f> 0b 41 bd 94 ff ff ff > >>> kernel: RSP: 0000:ffff91eec083fc98 EFLAGS: 00010082 >>> kernel: RAX: ffff8af20357d960 RBX: 0000000000000000 RCX: >>> ffff8af202f06400 >>> kernel: RDX: 0000000000000a20 RSI: ffff8af208785780 RDI: >>> ffff8af202e9ae00 >>> kernel: RBP: ffff8af202e9ae00 R08: 00000000000000c0 R09: >>> ffff8af208785780 >>> kernel: R10: 00000000ffffe000 R11: 3fffffffffffffff R12: >>> ffff8af208785780 >>> kernel: R13: 0000000000000000 R14: ffff8af202e9ae00 R15: >>> ffff8af203e26cc0 >>> kernel: FS:  0000000000000000(0000) GS:ffff8af23e200000(0000) >>> knlGS:0000000000000000 >>> kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>> kernel: CR2: 000055e2c21f2100 CR3: 0000000003b38000 CR4: >>> 00000000001006f0 >>> kernel: Call Trace: >>> kernel:  u_audio_start_playback+0x107/0x1a0 [u_audio] >>> kernel:  composite_setup+0x224/0x1ba0 [libcomposite] >>> kernel:  ? dwc3_gadget_ep_queue+0xf6/0x1a0 >>> kernel:  ? usb_ep_queue+0x2a/0x80 >>> kernel:  ? configfs_composite_setup+0x6b/0x90 [libcomposite] >>> kernel:  configfs_composite_setup+0x6b/0x90 [libcomposite] >>> kernel:  dwc3_ep0_interrupt+0x469/0xa80 >>> kernel:  dwc3_thread_interrupt+0x8ee/0xf40 >>> kernel:  ? __wake_up_common_lock+0x85/0xb0 >>> kernel:  ? disable_irq_nosync+0x10/0x10 >>> kernel:  irq_thread_fn+0x1b/0x60 >>> kernel:  irq_thread+0xd6/0x170 >>> kernel:  ? irq_thread_check_affinity+0x70/0x70 >>> kernel:  ? irq_forced_thread_fn+0x70/0x70 >>> kernel:  kthread+0x116/0x130 >>> kernel:  ? kthread_create_worker_on_cpu+0x60/0x60 >>> kernel:  ret_from_fork+0x22/0x30 >>> kernel: ---[ end trace e5b9e28058c53584 ]--- >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: dwc3 dwc3.0.auto: request 000000003c32dcc5 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: request 00000000b2512aa9 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: Fifosize(2154) > RAM size(2022) ep5in >>> depth:115540359 >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: dwc3 dwc3.0.auto: request 00000000b2512aa9 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: request 00000000036ac129 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: Fifosize(2154) > RAM size(2022) ep5in >>> depth:115540359 >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: dwc3 dwc3.0.auto: request 00000000ad1b8c18 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: request 00000000fbc71244 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: Fifosize(2154) > RAM size(2022) ep5in >>> depth:115540359 >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: dwc3 dwc3.0.auto: request 00000000fbc71244 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: request 00000000ad1b8c18 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: Fifosize(2154) > RAM size(2022) ep5in >>> depth:115540359 >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: configfs-gadget gadget: u_audio_start_playback:451 Error! >>> kernel: dwc3 dwc3.0.auto: request 000000003c32dcc5 was not queued to >>> ep5in >>> kernel: dwc3 dwc3.0.auto: request 00000000b2512aa9 was not queued to >>> ep5in >>> >>> Removing uac2 from the config makes the call trace go away, but the R/W >>> speed does not change. >>> >>>> :), not a problem...I've been working on getting the ideal set up for >>>> the performance profiling for awhile, so anything I can do to make sure >>>> we get some good results. >>>> >>>>> I'll try with a ramdisk and let you know. >>>>> >>>> Thanks again for the testing, Ferry. >>>> >>>> Thanks >>>> Wesley Cheng >>>> >>>>>> Thanks >>>>>> Wesley Cheng >>>>>> >>>>>>>> Changes in V9: >>>>>>>>     - Fixed incorrect patch in series.  Removed changes in DTSI, as >>>>>>>> dwc3-qcom will >>>>>>>>       add the property by default from the kernel. >>>>>>>> >>>>>>>> Changes in V8: >>>>>>>>     - Rebased to usb-testing >>>>>>>>     - Using devm_kzalloc for adding txfifo property in dwc3-qcom >>>>>>>>     - Removed DWC3 QCOM ACPI property for enabling the txfifo >>>>>>>> resize >>>>>>>> >>>>>>>> Changes in V7: >>>>>>>>     - Added a new property tx-fifo-max-num for limiting how much >>>>>>>> fifo >>>>>>>> space the >>>>>>>>       resizing logic can allocate for endpoints with large burst >>>>>>>> values.  This >>>>>>>>       can differ across platforms, and tie in closely with overall >>>>>>>> system latency. >>>>>>>>     - Added recommended checks for DWC32. >>>>>>>>     - Added changes to set the tx-fifo-resize property from >>>>>>>> dwc3-qcom by >>>>>>>> default >>>>>>>>       instead of modifying the current DTSI files. >>>>>>>>     - Added comments on all APIs/variables introduced. >>>>>>>>     - Updated the DWC3 YAML to include a better description of the >>>>>>>> tx-fifo-resize >>>>>>>>       property and added an entry for tx-fifo-max-num. >>>>>>>> >>>>>>>> Changes in V6: >>>>>>>>     - Rebased patches to usb-testing. >>>>>>>>     - Renamed to PATCH series instead of RFC. >>>>>>>>     - Checking for fs_descriptors instead of ss_descriptors for >>>>>>>> determining the >>>>>>>>       endpoint count for a particular configuration. >>>>>>>>     - Re-ordered patch series to fix patch dependencies. >>>>>>>> >>>>>>>> Changes in V5: >>>>>>>>     - Added check_config() logic, which is used to communicate the >>>>>>>> number of EPs >>>>>>>>       used in a particular configuration.  Based on this, the DWC3 >>>>>>>> gadget driver >>>>>>>>       has the ability to know the maximum number of eps utilized in >>>>>>>> all >>>>>>>> configs. >>>>>>>>       This helps reduce unnecessary allocation to unused eps, >>>>>>>> and will >>>>>>>> catch fifo >>>>>>>>       allocation issues at bind() time. >>>>>>>>     - Fixed variable declaration to single line per variable, and >>>>>>>> reverse xmas. >>>>>>>>     - Created a helper for fifo clearing, which is used by ep0.c >>>>>>>> >>>>>>>> Changes in V4: >>>>>>>>     - Removed struct dwc3* as an argument for >>>>>>>> dwc3_gadget_resize_tx_fifos() >>>>>>>>     - Removed WARN_ON(1) in case we run out of fifo space >>>>>>>>     Changes in V3: >>>>>>>>     - Removed "Reviewed-by" tags >>>>>>>>     - Renamed series back to RFC >>>>>>>>     - Modified logic to ensure that fifo_size is reset if we >>>>>>>> pass the >>>>>>>> minimum >>>>>>>>       threshold.  Tested with binding multiple FDs requesting 6 >>>>>>>> FIFOs. >>>>>>>> >>>>>>>> Changes in V2: >>>>>>>>     - Modified TXFIFO resizing logic to ensure that each EP is >>>>>>>> reserved a >>>>>>>>       FIFO. >>>>>>>>     - Removed dev_dbg() prints and fixed typos from patches >>>>>>>>     - Added some more description on the dt-bindings commit message >>>>>>>> >>>>>>>> Currently, there is no functionality to allow for resizing the >>>>>>>> TXFIFOs, and >>>>>>>> relying on the HW default setting for the TXFIFO depth.  In most >>>>>>>> cases, the >>>>>>>> HW default is probably sufficient, but for USB compositions that >>>>>>>> contain >>>>>>>> multiple functions that require EP bursting, the default settings >>>>>>>> might not be enough.  Also to note, the current SW will assign an >>>>>>>> EP to a >>>>>>>> function driver w/o checking to see if the TXFIFO size for that >>>>>>>> particular >>>>>>>> EP is large enough. (this is a problem if there are multiple HW >>>>>>>> defined >>>>>>>> values for the TXFIFO size) >>>>>>>> >>>>>>>> It is mentioned in the SNPS databook that a minimum of TX FIFO >>>>>>>> depth = 3 >>>>>>>> is required for an EP that supports bursting.  Otherwise, there >>>>>>>> may be >>>>>>>> frequent occurences of bursts ending.  For high bandwidth >>>>>>>> functions, >>>>>>>> such as data tethering (protocols that support data aggregation), >>>>>>>> mass >>>>>>>> storage, and media transfer protocol (over FFS), the bMaxBurst >>>>>>>> value >>>>>>>> can be >>>>>>>> large, and a bigger TXFIFO depth may prove to be beneficial in >>>>>>>> terms >>>>>>>> of USB >>>>>>>> throughput. (which can be associated to system access latency, >>>>>>>> etc...)  It >>>>>>>> allows for a more consistent burst of traffic, w/o any >>>>>>>> interruptions, as >>>>>>>> data is readily available in the FIFO. >>>>>>>> >>>>>>>> With testing done using the mass storage function driver, the >>>>>>>> results >>>>>>>> show >>>>>>>> that with a larger TXFIFO depth, the bandwidth increased >>>>>>>> significantly. >>>>>>>> >>>>>>>> Test Parameters: >>>>>>>>     - Platform: Qualcomm SM8150 >>>>>>>>     - bMaxBurst = 6 >>>>>>>>     - USB req size = 256kB >>>>>>>>     - Num of USB reqs = 16 >>>>>>>>     - USB Speed = Super-Speed >>>>>>>>     - Function Driver: Mass Storage (w/ ramdisk) >>>>>>>>     - Test Application: CrystalDiskMark >>>>>>>> >>>>>>>> Results: >>>>>>>> >>>>>>>> TXFIFO Depth = 3 max packets >>>>>>>> >>>>>>>> Test Case | Data Size | AVG tput (in MB/s) >>>>>>>> ------------------------------------------- >>>>>>>> Sequential|1 GB x     | >>>>>>>> Read      |9 loops    | 193.60 >>>>>>>>         |           | 195.86 >>>>>>>>              |           | 184.77 >>>>>>>>              |           | 193.60 >>>>>>>> ------------------------------------------- >>>>>>>> >>>>>>>> TXFIFO Depth = 6 max packets >>>>>>>> >>>>>>>> Test Case | Data Size | AVG tput (in MB/s) >>>>>>>> ------------------------------------------- >>>>>>>> Sequential|1 GB x     | >>>>>>>> Read      |9 loops    | 287.35 >>>>>>>>         |           | 304.94 >>>>>>>>              |           | 289.64 >>>>>>>>              |           | 293.61 >>>>>>>> ------------------------------------------- >>>>>>>> >>>>>>>> Wesley Cheng (6): >>>>>>>>      usb: gadget: udc: core: Introduce check_config to verify USB >>>>>>>>        configuration >>>>>>>>      usb: gadget: configfs: Check USB configuration before adding >>>>>>>>      usb: dwc3: Resize TX FIFOs to meet EP bursting requirements >>>>>>>>      of: Add stub for of_add_property() >>>>>>>>      usb: dwc3: dwc3-qcom: Enable tx-fifo-resize property by >>>>>>>> default >>>>>>>>      dt-bindings: usb: dwc3: Update dwc3 TX fifo properties >>>>>>>> >>>>>>>>     .../devicetree/bindings/usb/snps,dwc3.yaml         |  15 +- >>>>>>>>     drivers/usb/dwc3/core.c                            |   9 + >>>>>>>>     drivers/usb/dwc3/core.h                            |  15 ++ >>>>>>>>     drivers/usb/dwc3/dwc3-qcom.c                       |   9 + >>>>>>>>     drivers/usb/dwc3/ep0.c                             |   2 + >>>>>>>>     drivers/usb/dwc3/gadget.c                          | 212 >>>>>>>> +++++++++++++++++++++ >>>>>>>>     drivers/usb/gadget/configfs.c                      |  22 +++ >>>>>>>>     drivers/usb/gadget/udc/core.c                      |  25 +++ >>>>>>>>     include/linux/of.h                                 |   5 + >>>>>>>>     include/linux/usb/gadget.h                         |   5 + >>>>>>>>     10 files changed, 317 insertions(+), 2 deletions(-) >>>>>>>> -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project