From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755303AbaDKU2f (ORCPT ); Fri, 11 Apr 2014 16:28:35 -0400 Received: from mailout2.w2.samsung.com ([211.189.100.12]:14379 "EHLO usmailout2.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755018AbaDKU2d (ORCPT ); Fri, 11 Apr 2014 16:28:33 -0400 X-AuditID: cbfec37b-b7f8f6d000007030-fc-5348507007c4 Message-id: <5348506C.6000604@samsung.com> Date: Fri, 11 Apr 2014 14:28:28 -0600 From: Shuah Khan Reply-to: shuah.kh@samsung.com User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.2.0 MIME-version: 1.0 To: Mauro Carvalho Chehab , One Thousand Gnomes , Greg KH Cc: tj@kernel.org, rafael.j.wysocki@intel.com, linux@roeck-us.net, toshi.kani@hp.com, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, shuahkhan@gmail.com, Shuah Khan Subject: Re: [RFC PATCH 0/2] managed token devres interfaces References: <20140409191740.GA10748@kroah.com> <5345CD32.8010305@samsung.com> <20140410120435.4c439a8b@alan.etchedpixels.co.uk> <20140410083841.488f9c43@samsung.com> <20140410124653.64aeb06d@alan.etchedpixels.co.uk> <20140410113949.7de1312b@samsung.com> In-reply-to: <20140410113949.7de1312b@samsung.com> Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7bit X-Originating-IP: [105.144.134.251] X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupkkeLIzCtJLcpLzFFi42I5/e+wr25BgEewwflJghaTpvxls2hevJ7N 4vKuOWwWPRu2slo8WXiGyeLxirfsFl9/Olj8Wn6U0WLbrYUsDpweO2fdZffYtW0nk8fiPS+Z PDat6mTz2D93DbtH68lNrB47vzewe3zeJBfAEcVlk5Kak1mWWqRvl8CVcfDjdeaC0+YVM+6p NTAe1+pi5OSQEDCRaPoyiRXCFpO4cG89WxcjF4eQwDJGian/LjNCOL1MEj8PfmOFcLYxSrx4 +5MdpIVXQEviUddHRhCbRUBVonH3WbA4m4C6xOfXO8BsIQE5iaYlq5lBbFGBCIlXZyeyQPQK SvyYfI8FZKiIQA+jxL2uA+wgDrPAaUaJnrX3wDqEBWwk9l+7wgKxejOTxOtZ7WDXcgoYSZzr 2cAGYjMLWEusnLSNEcKWl9i85i0zxGpliT+XTzF1MXIAfacscftr2ARGkVlIls9C0j0LSfcC RuZVjGKlxckFxUnpqRVGesWJucWleel6yfm5mxgh0Ve9g/HuV5tDjAIcjEo8vB80PIKFWBPL iitzDzFKcDArifA+MwYK8aYkVlalFuXHF5XmpBYfYmTi4JRqYLS2mSf4/dib6qgXWfsSH5U8 P6nn/yB+qsbXkyZGJ9QVXrDOdphzJ6tdVN/KUKhcYOOdgOMLGdVnGUlWHp6TKeLm76MTaLZY 5abgZ3+bm95vnivGnzr6w9Jhzmar5JciVtdP/Iz54fnk4olPW+ft9NihdtlbUcY2muvEUX+R rMlu1hkhm/axCSixFGckGmoxFxUnAgDj6/ROnAIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Here is an example driver use-case for this token resource: This is not polished, but should give an idea on this new token resource is intended to be used: - create token resources in em28xx_usb_probe() right before the required modules are loaded. It creates tuner, video and audio tokens to use as a large grain lock on tuner, video DMA engine, and audio DMA engine respectively. - lock video token in em28xx_init_usb_xfer() - unlock in em28xx_uninit_usb_xfer() - destroy token in em28xx_release_resources() I did some hotplug testing with this: dmesg | grep token [ 771.613332] usb 8-1: devm_token_create(): created token: tuner:8-1-0000:00:10.1-0 [ 771.613335] em2874 #0: devm_token_create() returned 0 [ 771.613340] usb 8-1: devm_token_create(): created token: video:8-1-0000:00:10.1 [ 851.202931] usb 8-1: devm_token_release(): release token [ 851.202936] usb 8-1: devm_token_release(): release token [ 1775.052273] usb 8-2: devm_token_create(): created token: tuner:8-2-0000:00:10.1-0 [ 1775.052276] em2874 #0: devm_token_create() returned 0 [ 1775.052285] usb 8-2: devm_token_create(): created token: video:8-2-0000:00:10.1 shuah@anduin:~$ dmesg | grep token [ 771.613332] usb 8-1: devm_token_create(): created token: tuner:8-1-0000:00:10.1-0 [ 771.613335] em2874 #0: devm_token_create() returned 0 [ 771.613340] usb 8-1: devm_token_create(): created token: video:8-1-0000:00:10.1 [ 851.202931] usb 8-1: devm_token_release(): release token [ 851.202936] usb 8-1: devm_token_release(): release token [ 1775.052273] usb 8-2: devm_token_create(): created token: tuner:8-2-0000:00:10.1-0 [ 1775.052276] em2874 #0: devm_token_create() returned 0 [ 1775.052285] usb 8-2: devm_token_create(): created token: video:8-2-0000:00:10.1 [ 1799.610007] usb 8-2: devm_token_release(): release token [ 1799.610013] usb 8-2: devm_token_release(): release token diff --git a/drivers/media/usb/em28xx/em28xx-cards.c b/drivers/media/usb/em28xx/em28xx-cards.c index 50aa5a5..3305250 100644 --- a/drivers/media/usb/em28xx/em28xx-cards.c +++ b/drivers/media/usb/em28xx/em28xx-cards.c @@ -2428,6 +2428,51 @@ static struct em28xx_hash_table em28xx_i2c_hash[] = { }; /* NOTE: introduce a separate hash table for devices with 16 bit eeproms */ +/* interfaces to create and destroy token resources */ +static int em28xx_create_token_resources(struct em28xx *dev) +{ + int rc = 0; + + /* create token devres for tuner */ + snprintf(dev->tuner_tkn_id, sizeof(dev->tuner_tkn_id), + "tuner:%s-%s-%d", + dev_name(&dev->udev->dev), + dev->udev->bus->bus_name, + dev->tuner_addr); + + rc = devm_token_create(&dev->udev->dev, dev->tuner_tkn_id); + em28xx_info("devm_token_create() returned %d\n", rc); + + if (dev->has_video || dev->board.has_dvb) { + snprintf(dev->video_tkn_id, sizeof(dev->video_tkn_id), + "video:%s-%s", + dev_name(&dev->udev->dev), + dev->udev->bus->bus_name); + rc = devm_token_create(&dev->udev->dev, dev->video_tkn_id); + } + if (dev->audio_mode.has_audio) { + snprintf(dev->audio_tkn_id, sizeof(dev->audio_tkn_id), + "audio:%s-%s", + dev_name(&dev->udev->dev), + dev->udev->bus->bus_name); + rc = devm_token_create(&dev->udev->dev, dev->audio_tkn_id); + } + return rc; +} + +static int em28xx_destroy_token_resources(struct em28xx *dev) +{ + int rc = 0; + + devm_token_destroy(&dev->udev->dev, dev->tuner_tkn_id); + if (dev->has_video || dev->board.has_dvb) + rc = devm_token_destroy(&dev->udev->dev, dev->video_tkn_id); + if (dev->audio_mode.has_audio) + rc = devm_token_destroy(&dev->udev->dev, dev->audio_tkn_id); + + return rc; +} int em28xx_tuner_callback(void *ptr, int component, int command, int arg) { struct em28xx_i2c_bus *i2c_bus = ptr; @@ -2949,6 +2994,10 @@ static void em28xx_release_resources(struct em28xx *dev) em28xx_i2c_unregister(dev, 1); em28xx_i2c_unregister(dev, 0); + /* destroy token resources */ + if (em28xx_destroy_token_resources(dev)) + em28xx_info("Error destroying token resources\n"); + usb_put_dev(dev->udev); /* Mark device as unused */ @@ -3431,6 +3480,10 @@ static int em28xx_usb_probe(struct usb_interface *interface, kref_init(&dev->ref); + /* create token resources before requesting for modules */ + if (em28xx_create_token_resources(dev)) + em28xx_info("Error creating token resources\n"); + request_modules(dev); /* Should be the last thing to do, to avoid newer udev's to diff --git a/drivers/media/usb/em28xx/em28xx-core.c b/drivers/media/usb/em28xx/em28xx-core.c index 523d7e9..8129a9c 100644 --- a/drivers/media/usb/em28xx/em28xx-core.c +++ b/drivers/media/usb/em28xx/em28xx-core.c @@ -824,6 +824,9 @@ void em28xx_uninit_usb_xfer(struct em28xx *dev, enum em28xx_mode mode) usb_bufs->num_bufs = 0; em28xx_capture_start(dev, 0); + + /* unlock token */ + devm_token_unlock(&dev->udev->dev, dev->video_tkn_id); } EXPORT_SYMBOL_GPL(em28xx_uninit_usb_xfer); @@ -993,6 +996,11 @@ int em28xx_init_usb_xfer(struct em28xx *dev, enum em28xx_mode mode, em28xx_isocdbg("em28xx: called em28xx_init_usb_xfer in mode %d\n", mode); + /* lock token */ + rc = devm_token_lock(&dev->udev->dev, dev->video_tkn_id); + if (rc) + return rc; + dev->usb_ctl.urb_data_copy = urb_data_copy; if (mode == EM28XX_DIGITAL_MODE) { diff --git a/drivers/media/usb/em28xx/em28xx.h b/drivers/media/usb/em28xx/em28xx.h index 2051fc9..b13ec6e 100644 --- a/drivers/media/usb/em28xx/em28xx.h +++ b/drivers/media/usb/em28xx/em28xx.h @@ -34,6 +34,7 @@ #include #include #include +#include #include #include @@ -547,6 +548,11 @@ struct em28xx { int devno; /* marks the number of this device */ enum em28xx_chip_id chip_id; + /* token resources */ + char tuner_tkn_id[64]; /* tuner token id */ + char video_tkn_id[64]; /* video dma engine token */ + char audio_tkn_id[64]; /* audio dma engine token id */ + unsigned int is_em25xx:1; /* em25xx/em276x/7x/8x family bridge */ unsigned char disconnected:1; /* device has been diconnected */ unsigned int has_video:1; thanks -- Shuah -- Shuah Khan Senior Linux Kernel Developer - Open Source Group Samsung Research America(Silicon Valley) shuah.kh@samsung.com | (970) 672-0658