From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A7B12C83F25 for ; Tue, 22 Jul 2025 00:35:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=0E7K6TbHqixxuahN/+ZevO0iNkgpGSMMaugBawV/8NE=; b=bFmounf8Mvc1j9 PtQYhv5sY6/0R7Mvd1pKrq+1W6Szlz+hkEm7/YUU/IXKkgfQlKnKI6bRhJG0mm+IkM50pZou7f4gl v4owTZ4Ma9cfmV+hAmJMHAO1BSJ0fBkBxF6CGXXMfJ0BUR/bp9NSq3X9sxxVQ8wdc+2toiig7UhsO g55uJKyieKdX6eUj7FX/T7xwyxqbbIK04jfJreMaEf8HbiABnr80HjSOMHa+IwpE9lG8TyW3w3L4g uqya9MVzDlTziIpTOzusO6JKyzYWzwH+9vNQ0k+ESOo8yQrbxWauQAg8bwSexL6QS5v0PybhbEAue f7j/zSgclmgUecQ6DSvA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1ue0yY-00000000xi2-0J8A; Tue, 22 Jul 2025 00:35:22 +0000 Received: from layka.disroot.org ([178.21.23.139]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1ue0yU-00000000xhc-44ic for linux-riscv@lists.infradead.org; Tue, 22 Jul 2025 00:35:20 +0000 Received: from mail01.disroot.lan (localhost [127.0.0.1]) by disroot.org (Postfix) with ESMTP id 46DFF2082C; Tue, 22 Jul 2025 02:35:14 +0200 (CEST) X-Virus-Scanned: SPAM Filter at disroot.org Received: from layka.disroot.org ([127.0.0.1]) by localhost (disroot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id 2AWGV58KjTtc; Tue, 22 Jul 2025 02:35:13 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=disroot.org; s=mail; t=1753144513; bh=NVJSthHoVBfvJ0DprsxJsTID3or77ayMtN3PtiGsObQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=kuqp7SvqE3+gsACQYmTXKrC6X6J/IBJVAvyya0mbiIsDkonQbEAg4tHtU90nE2fOO maPB8WmFiNZIQBVtbQ5nZ1VKVgu8ehAoh0wGLNES47exI9ghg7zuUL54J4gtoTdMz5 tJYNXt4HOTIzqW9tNieEM2P/1o7t0VXzKJeO0orz4Bkz5+SPeuGo15x0CxAontFdWS I/D91B2ADLRNe+Bu1Ta0N7jG3yVEU8LxLvF6XW7tawKRh0QjJP2JNDny4uwpMZXphy uaoLs/SQ3vpfwD+kycJR2prgJzg5LDK+22uzpxHx+3Y2p1pbHW2o3yIcylVoF1fzU3 34If+OcvH0l6w== Date: Tue, 22 Jul 2025 00:34:46 +0000 From: Yao Zi To: Ze Huang , Alex Elder , Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Yixun Lan , Thinh Nguyen , Philipp Zabel Cc: linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 2/2] usb: dwc3: add generic driver to support flattened Message-ID: References: <20250712-dwc3_generic-v6-0-cc87737cc936@linux.dev> <20250712-dwc3_generic-v6-2-cc87737cc936@linux.dev> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20250721_173519_441786_C829AFAF X-CRM114-Status: GOOD ( 31.28 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org T24gTW9uLCBKdWwgMjEsIDIwMjUgYXQgMDg6MDg6MDZQTSArMDgwMCwgWmUgSHVhbmcgd3JvdGU6 Cj4gT24gU3VuLCBKdWwgMjAsIDIwMjUgYXQgMDI6MzQ6MDdQTSArMDgwMCwgWmUgSHVhbmcgd3Jv dGU6Cj4gPiBPbiBUdWUsIEp1bCAxNSwgMjAyNSBhdCAwMzo1MDo1NFBNIC0wNTAwLCBBbGV4IEVs ZGVyIHdyb3RlOgo+ID4gPiBPbiA3LzEyLzI1IDI6NDkgQU0sIFplIEh1YW5nIHdyb3RlOgo+ID4g PiA+IFRvIHN1cHBvcnQgZmxhdHRlbmVkIGR3YzMgZHQgbW9kZWwgYW5kIGRyb3AgdGhlIGdsdWUg bGF5ZXIsIGludHJvZHVjZSB0aGUKPiA+ID4gPiBgZHdjMy1nZW5lcmljYCBkcml2ZXIuIFRoaXMg ZW5hYmxlcyBkaXJlY3QgYmluZGluZyBvZiB0aGUgRFdDMyBjb3JlIGRyaXZlcgo+ID4gPiA+IGFu ZCBvZmZlcnMgYW4gYWx0ZXJuYXRpdmUgdG8gdGhlIGV4aXN0aW5nIGdsdWUgZHJpdmVyIGBkd2Mz LW9mLXNpbXBsZWAuCj4gPiA+IAo+ID4gPiBJJ20gbm90IGZhbWlsaWFyIHdpdGggZHdjLW9mLXNp bXBsZS5jLCBhbmQgd29uJ3QgY29tbWVudCBvbgo+ID4gPiBob3cgdGhpcyBkaWZmZXJzIGZyb20g dGhhdCAob3IgZG9lcyBub3QpLgo+ID4gPiAKPiA+ID4gR2l2ZW4geW91J3JlIGltcGxlbWVudGlu ZyBhbiBhbHRlcm5hdGl2ZSB0aG91Z2gsIGNhbiB5b3UgZXhwbGFpbgo+ID4gPiBpbiBhIGxpdHRs ZSBtb3JlIGRldGFpbCB3aGF0J3MgZGlmZmVyZW50IGJldHdlZW4gdGhlIHR3bz8gIFdoeQo+ID4g PiB3b3VsZCBzb21lb25lIGNob29zZSB0byB1c2UgdGhpcyBkcml2ZXIgcmF0aGVyIHRoYW4gdGhl IG90aGVyIG9uZT8KPiA+IAo+ID4gVGhleSBhcmUgYmFzaWNhbGx5IHRoZSBzYW1lLgo+ID4gCj4g PiBkd2MtZ2VuZXJpYyB1c2UgYSBwbGFpbiBkdCBub2RlIHdoaWxlIGR3Yy1vZi1zaW1wbGUgd2ls bCBuZXN0IHRoZSBkd2MzCj4gPiBub2RlIGFzIGl0cyBjaGlsZC4KPiA+IAo+ID4gQm90aCB3aWxs IHVzZSBkd2MzX2NvcmVfcHJvYmUoKSB0byBmaW5pc2ggdGhlIHByb2JlIHByb2Nlc3MuIEJ1dCBu b3cgd2UKPiA+IGNhbiBzaW1wbGlmeSB0aGUgcHJvY2VzcyBieSBqdXN0IGNhbGxpbmcgaXQsIGlu c3RlYWQgb2YgY2FsbGluZwo+ID4gb2ZfcGxhdGZvcm1fcG9wdWxhdGUoKSBhbmQgY3JlYXRlIGFu b3RoZXIgc25wcyxkd2MzIGRldmljZSBkcml2ZXIuCj4gCj4gWy4uLl0KPiAKPiA+ID4gPiArCXJl dCA9IHJlc2V0X2NvbnRyb2xfYXNzZXJ0KGR3YzMtPnJlc2V0cyk7Cj4gPiA+ID4gKwlpZiAocmV0 KQo+ID4gPiA+ICsJCXJldHVybiBkZXZfZXJyX3Byb2JlKGRldiwgcmV0LCAiZmFpbGVkIHRvIGFz c2VydCByZXNldHNcbiIpOwo+ID4gPiA+ICsKPiA+ID4gPiArCXJldCA9IGRldm1fYWRkX2FjdGlv bl9vcl9yZXNldChkZXYsIGR3YzNfZ2VuZXJpY19yZXNldF9jb250cm9sX2Fzc2VydCwgZHdjMy0+ cmVzZXRzKTsKPiA+ID4gPiArCWlmIChyZXQpCj4gPiA+ID4gKwkJcmV0dXJuIHJldDsKPiA+ID4g Cj4gPiA+IFRoZSByZS1hc3NlcnQgc2hvdWxkbid0IGJlIHNldCB1cCB1bmxlc3MgdGhlIGRlYXNz ZXJ0IGJlbG93Cj4gPiA+IHN1Y2NlZWRzLgo+ID4gPiAKPiA+IAo+ID4gV2lsbCBtb3ZlIGJlaGlu ZCB0aGUgZGVhc3NlcnQuCj4gPiAKPiA+ID4gPiArCXVzbGVlcF9yYW5nZSgxMCwgMTAwMCk7Cj4g PiA+IAo+ID4gPiBUaGlzIHNlZW1zIGxpa2UgYSBsYXJnZSByYW5nZS4gIFlvdSBjb3VsZCBqdXN0 IGRvIG1zbGVlcCgxKTsKPiA+ID4gQWxzbywgY2FuIHlvdSBhZGQgYSBjb21tZW50IGV4cGxhaW5p bmcgd2h5IGEgZGVsYXkgaXMgbmVlZGVkLAo+ID4gPiBhbmQgd2h5IDEgbWlsbGlzZWNvbmQgaXMg dGhlIHJpZ2h0IGFtb3VudCBvZiB0aW1lIHRvIHNsZWVwPwo+ID4gPiAKPiA+IAo+ID4gSSB3aWxs IGNoZWNrIHRoZSByYW5nZSB3aXRoIHNwYWNlbWl0IGFuZCByZXBseSBzb29uLgo+ID4gCj4gCj4g dGhlIHJlc2V0cyBhcmUgYXN5bmNocm9ub3VzIHdpdGggbm8gc3RyaWN0IHRpbWluZy4gQnV0IHRv IGJlIHNhZmUsIGVhY2gKPiByZXNldCBzaG91bGQgc3RheSBhY3RpdmUgZm9yIGF0IGxlYXN0IDHi gK/CtXMuIEnigJlsbCBzd2l0Y2ggdG8gYSB1ZGVsYXkoMikKPiBhbmQgYWRkIGNvbW1lbnQgYWNj b3JkaW5nbHkuCgpUaGlzIG1heSBiZSBhIGxpdHRsZSBmYXJzaWdodDogZG8geW91IHRoaW5rIGl0 J3MgYmV0dGVyIHRvIG1ha2UgdGhlCnJlc2V0IHRpbWluZyBwYXJ0IG9mIHRoZSBvZl9tYXRjaF9k YXRhPyBUaGlzIGlzIG1vcmUgZmxleGlibGUgYW5kCnJlZHVjZXMgZnV0dXJlIGJ1cmRlbiB3aGVu IGludHJvZHVjaW5nIGEgbmV3IHBsYXRmb3JtIHRoYXQgY29tZXMgd2l0aCBhCmRpZmZlcmVudCBy ZXNldCB0aW1pbmcsIHdoaWNoIGlzIGEgdmVyeSBsaWtlbHkgY2FzZSB3ZSdsbCBmYWNlIHNpbmNl Cml0J3MgYSAiZ2VuZXJpYyIgZHJpdmVyLgoKPiA+ID4gPiArCXJldCA9IHJlc2V0X2NvbnRyb2xf ZGVhc3NlcnQoZHdjMy0+cmVzZXRzKTsKPiA+ID4gPiArCWlmIChyZXQpCj4gPiA+ID4gKwkJcmV0 dXJuIGRldl9lcnJfcHJvYmUoZGV2LCByZXQsICJmYWlsZWQgdG8gZGVhc3NlcnQgcmVzZXRzXG4i KTsKPiA+ID4gPiArCj4gPiA+ID4gKwlyZXQgPSBkZXZtX2Nsa19idWxrX2dldF9hbGwoZHdjMy0+ ZGV2LCAmZHdjMy0+Y2xrcyk7Cj4gPiA+ID4gKwlpZiAocmV0IDwgMCkKPiA+ID4gPiArCQlyZXR1 cm4gZGV2X2Vycl9wcm9iZShkZXYsIHJldCwgImZhaWxlZCB0byBnZXQgY2xvY2tzXG4iKTsKPiA+ ID4gCj4gPiA+IENhbGwgZGV2bV9jbGtfYnVsa19nZXRfYWxsX2VuYWJsZWQoKSBpbnN0ZWFkIG9m IGRvaW5nIHRoZSB0d28KPiA+ID4gc3RlcHMgc2VwYXJhdGVseSBoZXJlLgo+ID4gPiAKPiA+IAo+ ID4gV2lsbCBkbywgdGhhbmtzLgo+ID4gCj4gPiA+IAkJCQkJLUFsZXgKPiAKClJlZ2FyZHMsCllh byBaaQoKX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX18KbGlu dXgtcmlzY3YgbWFpbGluZyBsaXN0CmxpbnV4LXJpc2N2QGxpc3RzLmluZnJhZGVhZC5vcmcKaHR0 cDovL2xpc3RzLmluZnJhZGVhZC5vcmcvbWFpbG1hbi9saXN0aW5mby9saW51eC1yaXNjdgo= From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from layka.disroot.org (layka.disroot.org [178.21.23.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DDD1D2E36EB; Tue, 22 Jul 2025 00:35:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.21.23.139 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753144519; cv=none; b=Us5lPnIH2ocbNUrUg8f2fy0kjP40Y9zivwYYiv46F1muWzUimemnHGyB/bIzEVm0rCVQJNP/6ig9uYLQydMOVlMNb1Ukxml3tUNEBxMVRcUmiGW4b9tL093fjIQGFgIw9mzX0qvDrx27zX2mY03+/bMFzmqQTrKAN5Oqq5d2t34= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1753144519; c=relaxed/simple; bh=NVJSthHoVBfvJ0DprsxJsTID3or77ayMtN3PtiGsObQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=fVHD/rrwWpeRUgPginqCkBA2H0V7wAlMPkXSarB9HDUYVPjVpYFsWBRjajtjCbzjs0tybA51lkXRSJFhijlAAHQXY0B501g6gG7HW2mJsDGCyzLqLMEOmlHwSHmMRRUj7gMGf+GtfhVwZsfBHdL7yYjqRnhVKXwrpeKFeaQWzt4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org; spf=pass smtp.mailfrom=disroot.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b=kuqp7Svq; arc=none smtp.client-ip=178.21.23.139 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=disroot.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b="kuqp7Svq" Received: from mail01.disroot.lan (localhost [127.0.0.1]) by disroot.org (Postfix) with ESMTP id 46DFF2082C; Tue, 22 Jul 2025 02:35:14 +0200 (CEST) X-Virus-Scanned: SPAM Filter at disroot.org Received: from layka.disroot.org ([127.0.0.1]) by localhost (disroot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id 2AWGV58KjTtc; Tue, 22 Jul 2025 02:35:13 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=disroot.org; s=mail; t=1753144513; bh=NVJSthHoVBfvJ0DprsxJsTID3or77ayMtN3PtiGsObQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=kuqp7SvqE3+gsACQYmTXKrC6X6J/IBJVAvyya0mbiIsDkonQbEAg4tHtU90nE2fOO maPB8WmFiNZIQBVtbQ5nZ1VKVgu8ehAoh0wGLNES47exI9ghg7zuUL54J4gtoTdMz5 tJYNXt4HOTIzqW9tNieEM2P/1o7t0VXzKJeO0orz4Bkz5+SPeuGo15x0CxAontFdWS I/D91B2ADLRNe+Bu1Ta0N7jG3yVEU8LxLvF6XW7tawKRh0QjJP2JNDny4uwpMZXphy uaoLs/SQ3vpfwD+kycJR2prgJzg5LDK+22uzpxHx+3Y2p1pbHW2o3yIcylVoF1fzU3 34If+OcvH0l6w== Date: Tue, 22 Jul 2025 00:34:46 +0000 From: Yao Zi To: Ze Huang , Alex Elder , Greg Kroah-Hartman , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Yixun Lan , Thinh Nguyen , Philipp Zabel Cc: linux-usb@vger.kernel.org, devicetree@vger.kernel.org, linux-riscv@lists.infradead.org, spacemit@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 2/2] usb: dwc3: add generic driver to support flattened Message-ID: References: <20250712-dwc3_generic-v6-0-cc87737cc936@linux.dev> <20250712-dwc3_generic-v6-2-cc87737cc936@linux.dev> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Mon, Jul 21, 2025 at 08:08:06PM +0800, Ze Huang wrote: > On Sun, Jul 20, 2025 at 02:34:07PM +0800, Ze Huang wrote: > > On Tue, Jul 15, 2025 at 03:50:54PM -0500, Alex Elder wrote: > > > On 7/12/25 2:49 AM, Ze Huang wrote: > > > > To support flattened dwc3 dt model and drop the glue layer, introduce the > > > > `dwc3-generic` driver. This enables direct binding of the DWC3 core driver > > > > and offers an alternative to the existing glue driver `dwc3-of-simple`. > > > > > > I'm not familiar with dwc-of-simple.c, and won't comment on > > > how this differs from that (or does not). > > > > > > Given you're implementing an alternative though, can you explain > > > in a little more detail what's different between the two? Why > > > would someone choose to use this driver rather than the other one? > > > > They are basically the same. > > > > dwc-generic use a plain dt node while dwc-of-simple will nest the dwc3 > > node as its child. > > > > Both will use dwc3_core_probe() to finish the probe process. But now we > > can simplify the process by just calling it, instead of calling > > of_platform_populate() and create another snps,dwc3 device driver. > > [...] > > > > > + ret = reset_control_assert(dwc3->resets); > > > > + if (ret) > > > > + return dev_err_probe(dev, ret, "failed to assert resets\n"); > > > > + > > > > + ret = devm_add_action_or_reset(dev, dwc3_generic_reset_control_assert, dwc3->resets); > > > > + if (ret) > > > > + return ret; > > > > > > The re-assert shouldn't be set up unless the deassert below > > > succeeds. > > > > > > > Will move behind the deassert. > > > > > > + usleep_range(10, 1000); > > > > > > This seems like a large range. You could just do msleep(1); > > > Also, can you add a comment explaining why a delay is needed, > > > and why 1 millisecond is the right amount of time to sleep? > > > > > > > I will check the range with spacemit and reply soon. > > > > the resets are asynchronous with no strict timing. But to be safe, each > reset should stay active for at least 1 µs. I’ll switch to a udelay(2) > and add comment accordingly. This may be a little farsight: do you think it's better to make the reset timing part of the of_match_data? This is more flexible and reduces future burden when introducing a new platform that comes with a different reset timing, which is a very likely case we'll face since it's a "generic" driver. > > > > + ret = reset_control_deassert(dwc3->resets); > > > > + if (ret) > > > > + return dev_err_probe(dev, ret, "failed to deassert resets\n"); > > > > + > > > > + ret = devm_clk_bulk_get_all(dwc3->dev, &dwc3->clks); > > > > + if (ret < 0) > > > > + return dev_err_probe(dev, ret, "failed to get clocks\n"); > > > > > > Call devm_clk_bulk_get_all_enabled() instead of doing the two > > > steps separately here. > > > > > > > Will do, thanks. > > > > > -Alex > Regards, Yao Zi