From patchwork Thu Apr 12 16:12:33 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Noralf_Tr=C3=B8nnes?= X-Patchwork-Id: 10338969 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BC401600D0 for ; Thu, 12 Apr 2018 16:14:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id ABB9726E35 for ; Thu, 12 Apr 2018 16:14:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A0BC326E73; Thu, 12 Apr 2018 16:14:07 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 3F18E26E35 for ; Thu, 12 Apr 2018 16:14:07 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 067DB6EAB6; Thu, 12 Apr 2018 16:13:15 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from smtp.domeneshop.no (smtp.domeneshop.no [IPv6:2a01:5b40:0:3005::1]) by gabe.freedesktop.org (Postfix) with ESMTPS id DA6FE6E995; Thu, 12 Apr 2018 16:13:01 +0000 (UTC) Received: from 211.81-166-168.customer.lyse.net ([81.166.168.211]:54390 helo=localhost.localdomain) by smtp.domeneshop.no with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_CBC_SHA256:128) (Exim 4.84_2) (envelope-from ) id 1f6eqJ-0002mh-2Y; Thu, 12 Apr 2018 18:12:59 +0200 From: =?UTF-8?q?Noralf=20Tr=C3=B8nnes?= To: dri-devel@lists.freedesktop.org Subject: [RFC v4 21/25] drm/fb-helper: Add drm_fb_helper_fb_open/release() Date: Thu, 12 Apr 2018 18:12:33 +0200 Message-Id: <20180412161237.9314-10-noralf@tronnes.org> X-Mailer: git-send-email 2.15.1 In-Reply-To: <20180412161237.9314-1-noralf@tronnes.org> References: <20180412161237.9314-1-noralf@tronnes.org> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: daniel.vetter@ffwll.ch, intel-gfx@lists.freedesktop.org, laurent.pinchart@ideasonboard.com, mstaudt@suse.de Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP These helpers keep track of fbdev users and drm_driver.last_close will only restore fbdev when actually in use. Additionally the display is turned off when the last user is closing. fbcon is a user in this context. If struct fb_ops is defined in a library, fb_open() takes a ref on the library (fb_ops.owner) instead of the driver module. Fix that by ensuring that the driver module is pinned. The functions are not added to the DRM_FB_HELPER_DEFAULT_OPS() macro, because some of its users do set fb_open/release themselves. Signed-off-by: Noralf Trønnes --- drivers/gpu/drm/drm_fb_helper.c | 54 ++++++++++++++++++++++++++++++++++++++++- include/drm/drm_fb_helper.h | 29 ++++++++++++++++++++++ 2 files changed, 82 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 98e5bc92c9f2..b1124c08b1ed 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -177,7 +177,7 @@ int drm_fb_helper_restore_fbdev_mode_unlocked(struct drm_fb_helper *fb_helper) if (!drm_fbdev_emulation || !fb_helper) return -ENODEV; - if (READ_ONCE(fb_helper->deferred_setup)) + if (READ_ONCE(fb_helper->deferred_setup) || !READ_ONCE(fb_helper->open_count)) return 0; mutex_lock(&fb_helper->lock); @@ -368,6 +368,7 @@ void drm_fb_helper_prepare(struct drm_device *dev, struct drm_fb_helper *helper, INIT_WORK(&helper->dirty_work, drm_fb_helper_dirty_work); helper->dirty_clip.x1 = helper->dirty_clip.y1 = ~0; mutex_init(&helper->lock); + helper->open_count = 1; helper->funcs = funcs; helper->dev = dev; } @@ -620,6 +621,53 @@ int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper) } EXPORT_SYMBOL(drm_fb_helper_defio_init); +/** + * drm_fb_helper_fb_open - implementation for &fb_ops.fb_open + * @info: fbdev registered by the helper + * @user: 1=userspace, 0=fbcon + * + * Increase fbdev use count. + * If &fb_ops is wrapped in a library, pin the driver module. + */ +int drm_fb_helper_fb_open(struct fb_info *info, int user) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_device *dev = fb_helper->dev; + + if (info->fbops->owner != dev->driver->fops->owner) { + if (!try_module_get(dev->driver->fops->owner)) + return -ENODEV; + } + + fb_helper->open_count++; + + return 0; +} +EXPORT_SYMBOL(drm_fb_helper_fb_open); + +/** + * drm_fb_helper_fb_release - implementation for &fb_ops.fb_release + * @info: fbdev registered by the helper + * @user: 1=userspace, 0=fbcon + * + * Decrease fbdev use count and turn off if there are no users left. + * If &fb_ops is wrapped in a library, unpin the driver module. + */ +int drm_fb_helper_fb_release(struct fb_info *info, int user) +{ + struct drm_fb_helper *fb_helper = info->par; + struct drm_device *dev = fb_helper->dev; + + if (!(--fb_helper->open_count)) + drm_fb_helper_dpms(info, DRM_MODE_DPMS_OFF); + + if (info->fbops->owner != dev->driver->fops->owner) + module_put(dev->driver->fops->owner); + + return 0; +} +EXPORT_SYMBOL(drm_fb_helper_fb_release); + /** * drm_fb_helper_sys_read - wrapper around fb_sys_read * @info: fb_info struct pointer @@ -1436,6 +1484,10 @@ static int drm_fb_helper_single_fb_probe(struct drm_fb_helper *fb_helper, if (ret < 0) return ret; + /* Block restore without users if we do track it */ + if (fb_helper->fbdev->fbops->fb_open == drm_fb_helper_fb_open) + fb_helper->open_count = 0; + strcpy(fb_helper->fb->comm, "[fbcon]"); return 0; } diff --git a/include/drm/drm_fb_helper.h b/include/drm/drm_fb_helper.h index 5f66f253a97b..330983975d5e 100644 --- a/include/drm/drm_fb_helper.h +++ b/include/drm/drm_fb_helper.h @@ -184,6 +184,22 @@ struct drm_fb_helper { * See also: @deferred_setup */ int preferred_bpp; + + /** + * @open_count: + * + * Keeps track of fbdev use to know when to not restore fbdev and to + * disable the pipeline when the last user is gone. + * + * Drivers that use drm_fb_helper_fb_open() as their \.fb_open + * callback will get an initial value of 0 and get restore based on + * actual use. Others will get an initial value of 1 which means that + * fbdev will always be restored. Drivers that call + * drm_fb_helper_fb_open() in their \.fb_open, thus needs to set the + * initial value to 0 themselves in their &drm_fb_helper_funcs->fb_probe + * callback. + */ + unsigned int open_count; }; /** @@ -230,6 +246,9 @@ void drm_fb_helper_deferred_io(struct fb_info *info, struct list_head *pagelist); int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper); +int drm_fb_helper_fb_open(struct fb_info *info, int user); +int drm_fb_helper_fb_release(struct fb_info *info, int user); + ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf, size_t count, loff_t *ppos); ssize_t drm_fb_helper_sys_write(struct fb_info *info, const char __user *buf, @@ -376,6 +395,16 @@ static inline int drm_fb_helper_defio_init(struct drm_fb_helper *fb_helper) return -ENODEV; } +static inline int drm_fb_helper_fb_open(struct fb_info *info, int user) +{ + return -ENODEV; +} + +static inline int drm_fb_helper_fb_release(struct fb_info *info, int user) +{ + return -ENODEV; +} + static inline ssize_t drm_fb_helper_sys_read(struct fb_info *info, char __user *buf, size_t count, loff_t *ppos)