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 X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,UNPARSEABLE_RELAY, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA16EC43381 for ; Tue, 5 Mar 2019 02:22:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7ADAA206B8 for ; Tue, 5 Mar 2019 02:22:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726889AbfCECWk (ORCPT ); Mon, 4 Mar 2019 21:22:40 -0500 Received: from Mailgw01.mediatek.com ([1.203.163.78]:4072 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726096AbfCECWk (ORCPT ); Mon, 4 Mar 2019 21:22:40 -0500 X-UUID: faf9553fbd2a4c828c32aa0f7a48ee06-20190305 X-UUID: faf9553fbd2a4c828c32aa0f7a48ee06-20190305 Received: from mtkcas36.mediatek.inc [(172.27.4.253)] by mailgw01.mediatek.com (envelope-from ) (mailgw01.mediatek.com ESMTP with TLS) with ESMTP id 664090149; Tue, 05 Mar 2019 10:22:30 +0800 Received: from MTKCAS36.mediatek.inc (172.27.4.186) by MTKMBS33N2.mediatek.inc (172.27.4.76) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Tue, 5 Mar 2019 10:22:29 +0800 Received: from [10.17.3.153] (172.27.4.253) by MTKCAS36.mediatek.inc (172.27.4.170) with Microsoft SMTP Server id 15.0.1395.4 via Frontend Transport; Tue, 5 Mar 2019 10:22:28 +0800 Message-ID: <1551752548.2210.94.camel@mhfsdcap03> Subject: Re: [PATCH] usb: introduce usb_ep_type_string() function From: Chunfeng Yun To: Greg Kroah-Hartman CC: Felipe Balbi , Mathias Nyman , Joel Stanley , Andrew Jeffery , Matthias Brugger , "Yoshihiro Shimoda" , Arnd Bergmann , Martin Blumenstingl , Alan Stern , Roger Quadros , "Sebastian Andrzej Siewior" , "Gustavo A. R. Silva" , Johan Hovold , "Benjamin Herrenschmidt" , Colin Ian King , Jaejoong Kim , , , , , Date: Tue, 5 Mar 2019 10:22:28 +0800 In-Reply-To: <20190301162141.GB19937@kroah.com> References: <20190301162141.GB19937@kroah.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-MTK: N Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Fri, 2019-03-01 at 17:21 +0100, Greg Kroah-Hartman wrote: > On Fri, Mar 01, 2019 at 02:58:23PM +0800, Chunfeng Yun wrote: > > In some places, the code prints a human-readable USB endpoint > > transfer type (e.g. "bulk"). This involves a switch statement > > sometimes wrapped around in ({ ... }) block leading to code > > repetition. > > To make this scenario easier, here introduces usb_ep_type_string() > > function, which returns a human-readable name of provided > > endpoint type. > > It also changes a few places switch was used to use this > > new function. > > > > Signed-off-by: Chunfeng Yun > > --- > > drivers/usb/common/common.c | 16 ++++++++++++++++ > > drivers/usb/core/endpoint.c | 18 ++---------------- > > drivers/usb/core/hcd.c | 17 ++--------------- > > drivers/usb/dwc3/debugfs.c | 23 ++++------------------- > > drivers/usb/gadget/udc/aspeed-vhub/epn.c | 6 +----- > > drivers/usb/gadget/udc/dummy_hcd.c | 16 +--------------- > > drivers/usb/host/xhci-trace.h | 19 ++----------------- > > include/linux/usb/ch9.h | 8 ++++++++ > > 8 files changed, 36 insertions(+), 87 deletions(-) > > > > diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c > > index 48277bbc15e4..2174dd9ec176 100644 > > --- a/drivers/usb/common/common.c > > +++ b/drivers/usb/common/common.c > > @@ -16,6 +16,22 @@ > > #include > > #include > > > > +static const char *const ep_type_names[] = { > > + [USB_ENDPOINT_XFER_CONTROL] = "ctrl", > > + [USB_ENDPOINT_XFER_ISOC] = "isoc", > > + [USB_ENDPOINT_XFER_BULK] = "bulk", > > + [USB_ENDPOINT_XFER_INT] = "intr", > > +}; > > + > > +const char *usb_ep_type_string(int ep_type) > > +{ > > + if (ep_type < 0 || ep_type >= ARRAY_SIZE(ep_type_names)) > > + return "unknown"; > > + > > + return ep_type_names[ep_type]; > > +} > > +EXPORT_SYMBOL_GPL(usb_ep_type_string); > > + > > const char *usb_otg_state_string(enum usb_otg_state state) > > { > > static const char *const names[] = { > > diff --git a/drivers/usb/core/endpoint.c b/drivers/usb/core/endpoint.c > > index 1c2c04079676..afa43f9a47b2 100644 > > --- a/drivers/usb/core/endpoint.c > > +++ b/drivers/usb/core/endpoint.c > > @@ -60,23 +60,9 @@ static ssize_t type_show(struct device *dev, struct device_attribute *attr, > > char *buf) > > { > > struct ep_device *ep = to_ep_device(dev); > > - char *type = "unknown"; > > + int ep_type = usb_endpoint_type(ep->desc); > > > > - switch (usb_endpoint_type(ep->desc)) { > > - case USB_ENDPOINT_XFER_CONTROL: > > - type = "Control"; > > - break; > > - case USB_ENDPOINT_XFER_ISOC: > > - type = "Isoc"; > > - break; > > - case USB_ENDPOINT_XFER_BULK: > > - type = "Bulk"; > > - break; > > - case USB_ENDPOINT_XFER_INT: > > - type = "Interrupt"; > > - break; > > - } > > - return sprintf(buf, "%s\n", type); > > + return sprintf(buf, "%s\n", usb_ep_type_string(ep_type)); > > You just changed a user/kernel API here, the strings are now different > from what they used to be :( How about using these type string to keep them unchanged? I need help from Felipe and Mathias to check whether the changes in dwc3 and xhci have side effect or not, and waiting for their comments Thanks > > That's not ok, odds are you will break tools if you do this. > > > } > > static DEVICE_ATTR_RO(type); > > > > diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c > > index 015b126ce455..193ee92b2fdb 100644 > > --- a/drivers/usb/core/hcd.c > > +++ b/drivers/usb/core/hcd.c > > @@ -1875,23 +1875,10 @@ void usb_hcd_flush_endpoint(struct usb_device *udev, > > /* kick hcd */ > > unlink1(hcd, urb, -ESHUTDOWN); > > dev_dbg (hcd->self.controller, > > - "shutdown urb %pK ep%d%s%s\n", > > + "shutdown urb %pK ep%d%s-%s\n", > > urb, usb_endpoint_num(&ep->desc), > > is_in ? "in" : "out", > > - ({ char *s; > > - > > - switch (usb_endpoint_type(&ep->desc)) { > > - case USB_ENDPOINT_XFER_CONTROL: > > - s = ""; break; > > - case USB_ENDPOINT_XFER_BULK: > > - s = "-bulk"; break; > > - case USB_ENDPOINT_XFER_INT: > > - s = "-intr"; break; > > - default: > > - s = "-iso"; break; > > - }; > > - s; > > - })); > > + usb_ep_type_string(usb_endpoint_type(&ep->desc))); > > You also changed the message here for control endpoints, but that's not > a big deal, it's ok. > > > usb_put_urb (urb); > > > > /* list contents may have changed */ > > diff --git a/drivers/usb/dwc3/debugfs.c b/drivers/usb/dwc3/debugfs.c > > index 1c792710348f..d9e2a63835fe 100644 > > --- a/drivers/usb/dwc3/debugfs.c > > +++ b/drivers/usb/dwc3/debugfs.c > > @@ -750,28 +750,13 @@ static int dwc3_transfer_type_show(struct seq_file *s, void *unused) > > unsigned long flags; > > > > spin_lock_irqsave(&dwc->lock, flags); > > - if (!(dep->flags & DWC3_EP_ENABLED) || > > - !dep->endpoint.desc) { > > - seq_printf(s, "--\n"); > > + if (!(dep->flags & DWC3_EP_ENABLED) || !dep->endpoint.desc) { > > + seq_puts(s, "unknown\n"); > > goto out; > > } > > > > - switch (usb_endpoint_type(dep->endpoint.desc)) { > > - case USB_ENDPOINT_XFER_CONTROL: > > - seq_printf(s, "control\n"); > > - break; > > - case USB_ENDPOINT_XFER_ISOC: > > - seq_printf(s, "isochronous\n"); > > - break; > > - case USB_ENDPOINT_XFER_BULK: > > - seq_printf(s, "bulk\n"); > > - break; > > - case USB_ENDPOINT_XFER_INT: > > - seq_printf(s, "interrupt\n"); > > - break; > > - default: > > - seq_printf(s, "--\n"); > > - } > > + seq_printf(s, "%s\n", > > + usb_ep_type_string(usb_endpoint_type(dep->endpoint.desc))); > > It is debugfs, so no real API guarantees at all, but you did change the > output format, and that's not always good. got it > > > > > out: > > spin_unlock_irqrestore(&dwc->lock, flags); > > diff --git a/drivers/usb/gadget/udc/aspeed-vhub/epn.c b/drivers/usb/gadget/udc/aspeed-vhub/epn.c > > index 4a28e3fbeb0b..165b0a43670e 100644 > > --- a/drivers/usb/gadget/udc/aspeed-vhub/epn.c > > +++ b/drivers/usb/gadget/udc/aspeed-vhub/epn.c > > @@ -593,10 +593,6 @@ static int ast_vhub_epn_disable(struct usb_ep* u_ep) > > static int ast_vhub_epn_enable(struct usb_ep* u_ep, > > const struct usb_endpoint_descriptor *desc) > > { > > - static const char *ep_type_string[] __maybe_unused = { "ctrl", > > - "isoc", > > - "bulk", > > - "intr" }; > > struct ast_vhub_ep *ep = to_ast_ep(u_ep); > > struct ast_vhub_dev *dev; > > struct ast_vhub *vhub; > > @@ -646,7 +642,7 @@ static int ast_vhub_epn_enable(struct usb_ep* u_ep, > > ep->epn.wedged = false; > > > > EPDBG(ep, "Enabling [%s] %s num %d maxpacket=%d\n", > > - ep->epn.is_in ? "in" : "out", ep_type_string[type], > > + ep->epn.is_in ? "in" : "out", usb_ep_type_string(type), > > usb_endpoint_num(desc), maxpacket); > > > > /* Can we use DMA descriptor mode ? */ > > diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c > > index baf72f95f0f1..40c6a484e232 100644 > > --- a/drivers/usb/gadget/udc/dummy_hcd.c > > +++ b/drivers/usb/gadget/udc/dummy_hcd.c > > @@ -617,21 +617,7 @@ static int dummy_enable(struct usb_ep *_ep, > > _ep->name, > > desc->bEndpointAddress & 0x0f, > > (desc->bEndpointAddress & USB_DIR_IN) ? "in" : "out", > > - ({ char *val; > > - switch (usb_endpoint_type(desc)) { > > - case USB_ENDPOINT_XFER_BULK: > > - val = "bulk"; > > - break; > > - case USB_ENDPOINT_XFER_ISOC: > > - val = "iso"; > > - break; > > - case USB_ENDPOINT_XFER_INT: > > - val = "intr"; > > - break; > > - default: > > - val = "ctrl"; > > - break; > > - } val; }), > > + usb_ep_type_string(usb_endpoint_type(desc)), > > max, ep->stream_en ? "enabled" : "disabled"); > > > > /* at this point real hardware should be NAKing transfers > > diff --git a/drivers/usb/host/xhci-trace.h b/drivers/usb/host/xhci-trace.h > > index 88b427434bd8..bac73d688f11 100644 > > --- a/drivers/usb/host/xhci-trace.h > > +++ b/drivers/usb/host/xhci-trace.h > > @@ -289,23 +289,8 @@ DECLARE_EVENT_CLASS(xhci_log_urb, > > ), > > TP_printk("ep%d%s-%s: urb %p pipe %u slot %d length %d/%d sgs %d/%d stream %d flags %08x", > > __entry->epnum, __entry->dir_in ? "in" : "out", > > - ({ char *s; > > - switch (__entry->type) { > > - case USB_ENDPOINT_XFER_INT: > > - s = "intr"; > > - break; > > - case USB_ENDPOINT_XFER_CONTROL: > > - s = "control"; > > - break; > > - case USB_ENDPOINT_XFER_BULK: > > - s = "bulk"; > > - break; > > - case USB_ENDPOINT_XFER_ISOC: > > - s = "isoc"; > > - break; > > - default: > > - s = "UNKNOWN"; > > - } s; }), __entry->urb, __entry->pipe, __entry->slot_id, > > + usb_ep_type_string(__entry->type), > > + __entry->urb, __entry->pipe, __entry->slot_id, > > __entry->actual, __entry->length, __entry->num_mapped_sgs, > > __entry->num_sgs, __entry->stream, __entry->flags > > ) > > Another api change with "control" :( > > I like the idea, but you can not break user/kernel apis like this > without knowing the affects that could happen. > > thanks, > > greg k-h