From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2992585Ab2KOBaU (ORCPT ); Wed, 14 Nov 2012 20:30:20 -0500 Received: from mailout1.samsung.com ([203.254.224.24]:58225 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992522Ab2KOBaO (ORCPT ); Wed, 14 Nov 2012 20:30:14 -0500 X-AuditID: cbfee61b-b7f616d00000319b-d7-50a445a4acd4 From: Jingoo Han To: "'Thierry Reding'" , "'Andrew Morton'" Cc: "'Richard Purdie'" , "'Florian Tobias Schandinat'" , linux-fbdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-kernel@vger.kernel.org References: <1352469878-4532-1-git-send-email-thierry.reding@avionic-design.de> In-reply-to: <1352469878-4532-1-git-send-email-thierry.reding@avionic-design.de> Subject: Re: [PATCH] backlight: Add of_find_backlight_by_node() function Date: Thu, 15 Nov 2012 10:30:11 +0900 Message-id: <004201cdc2d0$c1920210$44b60630$%han@samsung.com> MIME-version: 1.0 Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 Thread-index: Ac2+g0iAWySaBkDDQt6otgruBRgKJgETNj4g Content-language: ko DLP-Filter: Pass X-MTR: 20000000000000000@CPGS X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrFIsWRmVeSWpSXmKPExsVy+t8zY90lrksCDDY+E7Y40feB1eLyrjls DkwenzfJBTBGcdmkpOZklqUW6dslcGWc6mhgLFgrVPHm0wG2BsbJ/F2MnBwSAiYSbVvvM0PY YhIX7q1nA7GFBJYxSizYHwtTs/PCIaAaLqD4dEaJc7tPMEE4vxgl3q7uAOtgE1CT+PLlMDuI LSKQJjFvWx8LSBGzwDFGifXrbjBCjPWXeNS6nAXE5hQIkPj84ytYXFjAQ2Lz5a9gg1gEVCU+ rJoCVMPBwStgK7F7QhRImFdAUOLH5HtgrcwCWhLrdx5ngrDlJTavecsMUi4hoC7x6K8uiCki YCSxY4cbRIWIxL4X7xghhgtIfJt8iAWiWlZi0wGwtyQENrFLnP15jw3iX0mJgytusExglJiF ZPEsJItnIVk8C8mKBYwsqxhFUwuSC4qT0nON9IoTc4tL89L1kvNzNzFCIkx6B+OqBotDjAIc jEo8vBYfFwcIsSaWFVfmHmKU4GBWEuF9cRAoxJuSWFmVWpQfX1Sak1p8iNEH6PKJzFKiyfnA 6M8riTc0NjYxMzE1Mbc0NTfFIawkztvskRIgJJCeWJKanZpakFoEM46Jg1OqgXHpgtd/Tt+P nRUn7uUhb7Y5c0mA8O+J/r/Ct16UED548FWJhczST3XcFdn9burcIWpVH30uylr0/Y83OV1Q GyK10bn+2vlFLDMU/u67OP1w9M6ZJi8eXv288dzPDzJ6FrP7Y3wLv0x+YcXD9t3u6bnDeaJ/ 1/xYtXBZhJLjrrrgdRMMVeXsVCqUWIozEg21mIuKEwEsl7mS3QIAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrFIsWRmVeSWpSXmKPExsVy+t9jQd0lrksCDHa/57U40feB1eLyrjls DkwenzfJBTBGNTDaZKQmpqQWKaTmJeenZOal2yp5B8c7x5uaGRjqGlpamCsp5CXmptoqufgE 6Lpl5gCNVlIoS8wpBQoFJBYXK+nbYZoQGuKmawHTGKHrGxIE12NkgAYS1jFmnOpoYCxYK1Tx 5tMBtgbGyfxdjJwcEgImEjsvHGKGsMUkLtxbz9bFyMUhJDCdUeLc7hNMEM4vRom3qzvYQKrY BNQkvnw5zA5iiwikSczb1scCUsQscIxRYv26G4wgCSEBf4lHrctZQGxOgQCJzz++gsWFBTwk Nl/+CjaIRUBV4sOqKUA1HBy8ArYSuydEgYR5BQQlfky+B9bKLKAlsX7ncSYIW15i85q3zCDl EgLqEo/+6oKYIgJGEjt2uEFUiEjse/GOcQKj0Cwkg2YhGTQLyaBZSFoWMLKsYhRNLUguKE5K zzXSK07MLS7NS9dLzs/dxAiO4GfSOxhXNVgcYhTgYFTi4bX4uDhAiDWxrLgy9xCjBAezkgjv i4NAId6UxMqq1KL8+KLSnNTiQ4w+QG9OZJYSTc4HJpe8knhDYxMzI0sjMwsjE3NzHMJK4rzN HikBQgLpiSWp2ampBalFMOOYODilGhhli5d283nWfN8+yfmK/KnUE5dD/nzV2yfotW1aW+fS A44HS5NmnZsfZWLGpJXwT2rLoZ12B/5uCU0/bWETmHtlu+VxxiNfDQ8FTl+fv+XV62eaku84 lt36+qLtY9RKMQXJtUdnJQrFOsrJrDq3ZWlvxKe35XkinhXZszlP9WvqFZdeZcv5VFqixFKc kWioxVxUnAgA6lv//g0DAAA= X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Friday, November 09, 2012 11:05 PM Thierry Reding wrote > > This function finds the struct backlight_device for a given device tree > node. A dummy function is provided so that it safely compiles out if OF > support is disabled. > > Signed-off-by: Thierry Reding CC'ed Andrew Morton Hi Thierry Reding, The patch itself looks good. Could you explain when this API is used? Thank you. Best regards, Jingoo Han > --- > drivers/video/backlight/backlight.c | 17 +++++++++++++++++ > include/linux/backlight.h | 10 ++++++++++ > 2 files changed, 27 insertions(+) > > diff --git a/drivers/video/backlight/backlight.c b/drivers/video/backlight/backlight.c > index 297db2f..0d1ed4f 100644 > --- a/drivers/video/backlight/backlight.c > +++ b/drivers/video/backlight/backlight.c > @@ -370,6 +370,23 @@ void backlight_device_unregister(struct backlight_device *bd) > } > EXPORT_SYMBOL(backlight_device_unregister); > > +#if IS_ENABLED(CONFIG_OF) > +static int of_parent_match(struct device *dev, void *data) > +{ > + return dev->parent && dev->parent->of_node == data; > +} > + > +struct backlight_device *of_find_backlight_by_node(struct device_node *node) > +{ > + struct device *dev; > + > + dev = class_find_device(backlight_class, NULL, node, of_parent_match); > + > + return dev ? to_backlight_device(dev) : NULL; > +} > +EXPORT_SYMBOL(of_find_backlight_by_node); > +#endif > + > static void __exit backlight_class_exit(void) > { > class_destroy(backlight_class); > diff --git a/include/linux/backlight.h b/include/linux/backlight.h > index 5ffc6dd..11840e9 100644 > --- a/include/linux/backlight.h > +++ b/include/linux/backlight.h > @@ -134,4 +134,14 @@ struct generic_bl_info { > void (*kick_battery)(void); > }; > > +#if IS_ENABLED(CONFIG_OF) > +struct backlight_device *of_find_backlight_by_node(struct device_node *node); > +#else > +static inline struct backlight_device * > +of_find_backlight_by_node(struct device_node *node) > +{ > + return NULL; > +} > +#endif > + > #endif > -- > 1.8.0 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fbdev" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html