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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 87F22C04FDF for ; Tue, 8 Aug 2023 20:51:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235504AbjHHUvI (ORCPT ); Tue, 8 Aug 2023 16:51:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51516 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235448AbjHHUuj (ORCPT ); Tue, 8 Aug 2023 16:50:39 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8B8DF10E9EF; Tue, 8 Aug 2023 09:46:22 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id F423562440; Tue, 8 Aug 2023 08:29:50 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8B03C433C8; Tue, 8 Aug 2023 08:29:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1691483390; bh=FiNrcT5Dlrnd8YbrKQdjS/NZ+m/l50JiT60Nd4pIS58=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PfrXdrBsHppC85W5vyjvDMZ+T3KCSq1OYjw9KWardf/6t5trHjyzT0beno+v2tHgM 6yYhlDf9JUwlVDrdbGX4NJRYNvHDqY8/1qCVfxdT7CDT4YTfJ8YG+eJKr6kfpYTUWF nCZnJuLZnDkl3VELamwskHxOhstOHbC1t25eF7fE= Date: Tue, 8 Aug 2023 10:29:47 +0200 From: Greg Kroah-Hartman To: Akash Kumar Cc: Thinh Nguyen , Jing Leng , Felipe Balbi , Pratham =?iso-8859-1?Q?Pratap=A0?= , Jack Pham , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] usb: gadget: f_uac2: uevent changes for uac2 Message-ID: <2023080837-droplet-mace-dfbb@gregkh> References: <20230723190538.27750-1-quic_akakum@quicinc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230723190538.27750-1-quic_akakum@quicinc.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 24, 2023 at 12:35:38AM +0530, Akash Kumar wrote: > Adding uevent from usb audio gadget driver for uac2 playback/capture > events, which userspace reads and later reads sysfs entry to know if > playback or capture has stopped or started by host application. How do you keep the events in sync then? If you get a uevent, and then wait a while before reading sysfs, how do you know that a different uevent didn't happen inbetween? > /config/usb_gadget/g1/functions/uac2.0 # cat c_status > 1 --> capture started > 0 --> capture stopped > /config/usb_gadget/g1/functions/uac2.0 # cat p_status > 1 --> playback started > 0 --> playback stopped > > Signed-off-by: Akash Kumar > --- > .../ABI/testing/configfs-usb-gadget-uac2 | 4 ++ > drivers/usb/gadget/function/f_uac2.c | 47 +++++++++++++++++++ > drivers/usb/gadget/function/u_uac2.h | 5 ++ > 3 files changed, 56 insertions(+) > > diff --git a/Documentation/ABI/testing/configfs-usb-gadget-uac2 b/Documentation/ABI/testing/configfs-usb-gadget-uac2 > index 2bfdd4efa9bd..196c6921a163 100644 > --- a/Documentation/ABI/testing/configfs-usb-gadget-uac2 > +++ b/Documentation/ABI/testing/configfs-usb-gadget-uac2 > @@ -10,3 +10,7 @@ Description: > p_chmask - playback channel mask > p_srate - playback sampling rate > p_ssize - playback sample size (bytes) > + c_status - usb uac2 audio capture state > + (0: capture stopped, 1: capture started) > + p_status - usb uac2 audio playback state > + (0: playback stopped, 1: playback started) > diff --git a/drivers/usb/gadget/function/f_uac2.c b/drivers/usb/gadget/function/f_uac2.c > index db2d4980cb35..f1f7631e9380 100644 > --- a/drivers/usb/gadget/function/f_uac2.c > +++ b/drivers/usb/gadget/function/f_uac2.c > @@ -739,6 +739,8 @@ afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt) > struct usb_gadget *gadget = cdev->gadget; > struct device *dev = &gadget->dev; > int ret = 0; > + struct f_uac2_opts *audio_opts = > + container_of(fn->fi, struct f_uac2_opts, func_inst); > > /* No i/f has more than 2 alt settings */ > if (alt > 1) { > @@ -762,6 +764,8 @@ afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt) > ret = u_audio_start_capture(&uac2->g_audio); > else > u_audio_stop_capture(&uac2->g_audio); > + audio_opts->c_status = alt; > + schedule_work(&audio_opts->work); > } else if (intf == uac2->as_in_intf) { > uac2->as_in_alt = alt; > > @@ -769,6 +773,8 @@ afunc_set_alt(struct usb_function *fn, unsigned intf, unsigned alt) > ret = u_audio_start_playback(&uac2->g_audio); > else > u_audio_stop_playback(&uac2->g_audio); > + audio_opts->p_status = alt; > + schedule_work(&audio_opts->work); > } else { > dev_err(dev, "%s:%d Error!\n", __func__, __LINE__); > return -EINVAL; > @@ -801,11 +807,16 @@ static void > afunc_disable(struct usb_function *fn) > { > struct f_uac2 *uac2 = func_to_uac2(fn); > + struct f_uac2_opts *audio_opts = > + container_of(fn->fi, struct f_uac2_opts, func_inst); > > uac2->as_in_alt = 0; > uac2->as_out_alt = 0; > + audio_opts->p_status = 0;//alt; > + audio_opts->c_status = 0; //alt; > u_audio_stop_capture(&uac2->g_audio); > u_audio_stop_playback(&uac2->g_audio); > + schedule_work(&audio_opts->work); > } > > static int > @@ -1036,6 +1047,25 @@ UAC2_ATTRIBUTE(c_srate); > UAC2_ATTRIBUTE(c_ssize); > UAC2_ATTRIBUTE(req_number); > > +#define UAC2_ATTRIBUTE_RO(name) \ > + static ssize_t f_uac2_opts_##name##_show( \ > + struct config_item *item, \ > + char *page) \ > +{ \ > + struct f_uac2_opts *opts = to_f_uac2_opts(item); \ > + int result; \ > + \ > + mutex_lock(&opts->lock); \ > + result = scnprintf(page, PAGE_SIZE, "%u\n", opts->name); \ > + mutex_unlock(&opts->lock); \ > + \ > + return result; \ > +} \ > +CONFIGFS_ATTR_RO(f_uac2_opts_, name) > + > +UAC2_ATTRIBUTE_RO(c_status); > +UAC2_ATTRIBUTE_RO(p_status); > + > static struct configfs_attribute *f_uac2_attrs[] = { > &f_uac2_opts_attr_p_chmask, > &f_uac2_opts_attr_p_srate, > @@ -1044,6 +1074,8 @@ static struct configfs_attribute *f_uac2_attrs[] = { > &f_uac2_opts_attr_c_srate, > &f_uac2_opts_attr_c_ssize, > &f_uac2_opts_attr_req_number, > + &f_uac2_opts_attr_c_status, > + &f_uac2_opts_attr_p_status, You didn't document these new attributes either in Documentation/ABI/ Also, what userspace tool is going to use these? thanks, greg k-h