From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jingoo Han" Subject: Re: [PATCH 1/6] backlight: Nuke unused backlight.props.state states Date: Wed, 25 Apr 2018 15:42:15 -0400 Message-ID: <000001d3dccd$83e2c680$8ba85380$@gmail.com> References: <20180425174253.4616-1-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from mail-qk0-x243.google.com (mail-qk0-x243.google.com [IPv6:2607:f8b0:400d:c09::243]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3E8426E686 for ; Wed, 25 Apr 2018 19:42:18 +0000 (UTC) Received: by mail-qk0-x243.google.com with SMTP id b39so23621572qkb.5 for ; Wed, 25 Apr 2018 12:42:18 -0700 (PDT) In-Reply-To: <20180425174253.4616-1-daniel.vetter@ffwll.ch> Content-language: en-us List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: 'Daniel Vetter' , 'DRI Development' , 'LKML' Cc: 'Meghana Madhyastha' , 'Daniel Vetter' , 'Daniel Thompson' , 'Lee Jones' List-Id: dri-devel@lists.freedesktop.org T24gV2VkbmVzZGF5LCBBcHJpbCAyNSwgMjAxOCAxOjQzIFBNLCBEYW5pZWwgVmV0dGVyIHdyb3Rl Ogo+IAo+IFRoZSBiYWNrbGlnaHQgcG93ZXIgc3RhdGUgaGFuZGxpbmcgaXMgc3VwcmVtZWx5IGNv bmZ1c2luZy4gV2UgaGF2ZToKPiAtIHByb3BzLnBvd2VyLCB1c2luZyBGQl9CTEFOS18qIGRlZmlu ZXMKPiAtIHByb3BzLmZiX2JsYW5rLCB1c2luZyB0aGUgc2FtZSwgYnV0IGRlcHJlY2F0ZWQgaW50 IGZhdm91ciBvZgo+ICAgcHJvcHMuc3RhdGUKPiAtIHByb3BzLnN0YXRlLCB1c2luZyB0aGUgQkxf Q09SRV8qIGRlZmluZXMKPiAtIGFuZCBmaW5hbGx5IGEgYnVuY2ggb2YgYmFja2xpZ2h0IGRyaXZl cnMgdHJlYXQgYnJpZ2h0bmVzcyA9PSAwIGFzCj4gICBvZmYuIEJ1dCBvZiBjb3Vyc2Ugbm90IGFs bCBvZiB0aGVtLgo+IAo+IFRoaXMgaXMgd2F5IHRvbyBtdWNoIGNvbmZ1c2lvbiB0byBmaXggaW4g YSBzaW1wbGUgcGF0Y2gsIGJ1dCBhdCBsZWFzdAo+IHByZXZlbnQgbW9yZSBoaWxhcml0eSBmcm9t IHNwcmVhZGluZyBieSByZW1vdmluZyB0aGUgdW51c2VkIEJMX0NPUkVfKgo+IGRlZmluZXMuIEkg aGF2ZSBubyBpZGVhIHdoeSBleGFjdGx5IGFueW9uZSB3b3VsZCBuZWVkIHRoYXQuCj4gCj4gV3J0 IHRoZSBpZGVhbCBzdGF0ZSwgd2UgcmVhbGx5IGp1c3Qgd2FudCBhIGJvb2xlYW4gc3RhdGUuIFRo ZSA0IHBvd2VyCj4gc2F2aW5nIHN0YXRlcyB0aGF0IHRoZSBmYmRldiBzdWJzeXN0ZW0gdXNlcyBh cmUgb3ZlcmtpbGwgaW4gdG9kYXlzIGh3Cj4gKHRoaXMgd2FzIG9ubHkgcmVsZXZhbnQgZm9yIFZH QSBhbmQgc2ltaWxhciBhbmFsb2cgY2lyY3VpdHMgbGlrZQo+IFRWLW91dCksIHRoZSBuZXcgZHJt IGF0b21pYyBtb2Rlc2V0IGFwaSBzaW1wbGlmaWVkIGV2ZW4gdGhlIHVhcGkgdG8gYQo+IHNpbXBs ZSBib29sLiBBbmQgdGhlcmUgd2FzIG5ldmVyIGEgdmFsaWQgdGVjaG5pY2FsIHJlYXNvbiB0byBo YXZlIHRoZQo+IGludGVybWVkaWF0ZSBmYmRldiBwb3dlciBzdGF0ZXMgZm9yIGJhY2tsaWdodHMg KHRob3NlIHJlYWxseSBvbmx5IGNhbgo+IGJlIGVpdGhlciBvZmYgb3Igb24pLgo+IAo+IENsZWFu dXAgbW90aXZhdGVkIGJ5IE1lZ2hhbmEncyBxdWVzdGlvbnMgYWJvdXQgYWxsIHRoaXMuCj4gCj4g Q2M6IExlZSBKb25lcyA8bGVlLmpvbmVzQGxpbmFyby5vcmc+Cj4gQ2M6IERhbmllbCBUaG9tcHNv biA8ZGFuaWVsLnRob21wc29uQGxpbmFyby5vcmc+Cj4gQ2M6IEppbmdvbyBIYW4gPGppbmdvb2hh bjFAZ21haWwuY29tPgo+IENjOiBNZWdoYW5hIE1hZGh5YXN0aGEgPG1lZ2hhbmEubWFkaHlhc3Ro YUBnbWFpbC5jb20+Cj4gQWNrZWQtYnk6IERhbmllbCBUaG9tcHNvbiA8ZGFuaWVsLnRob21wc29u QGxpbmFyby5vcmc+Cj4gU2lnbmVkLW9mZi1ieTogRGFuaWVsIFZldHRlciA8ZGFuaWVsLnZldHRl ckBpbnRlbC5jb20+CgpBY2tlZC1ieTogSmluZ29vIEhhbiA8amluZ29vaGFuMUBnbWFpbC5jb20+ CgpJIHJlYWxseSBsb3ZlIHRoaXMgcGF0Y2ghCkdvb2Qgam9iIQpUaGFuayB5b3UuCgpCZXN0IHJl Z2FyZHMsCkppbmdvbyBIYW4KCj4gLS0tCj4gIGluY2x1ZGUvbGludXgvYmFja2xpZ2h0LmggfCAz IC0tLQo+ICAxIGZpbGUgY2hhbmdlZCwgMyBkZWxldGlvbnMoLSkKPiAKPiBkaWZmIC0tZ2l0IGEv aW5jbHVkZS9saW51eC9iYWNrbGlnaHQuaCBiL2luY2x1ZGUvbGludXgvYmFja2xpZ2h0LmgKPiBp bmRleCAyYmFhYjZmMzg2MWQuLjFkYjY3NjYyYmZjYiAxMDA2NDQKPiAtLS0gYS9pbmNsdWRlL2xp bnV4L2JhY2tsaWdodC5oCj4gKysrIGIvaW5jbHVkZS9saW51eC9iYWNrbGlnaHQuaAo+IEBAIC04 NCw5ICs4NCw2IEBAIHN0cnVjdCBiYWNrbGlnaHRfcHJvcGVydGllcyB7Cj4gCj4gICNkZWZpbmUg QkxfQ09SRV9TVVNQRU5ERUQJKDEgPDwgMCkJLyogYmFja2xpZ2h0IGlzIHN1c3BlbmRlZCAqLwo+ ICAjZGVmaW5lIEJMX0NPUkVfRkJCTEFOSwkJKDEgPDwgMSkJLyogYmFja2xpZ2h0IGlzCnVuZGVy IGFuIGZiCj4gYmxhbmsgZXZlbnQgKi8KPiAtI2RlZmluZSBCTF9DT1JFX0RSSVZFUjQJCSgxIDw8 IDI4KQkvKiByZXNlcnZlZCBmb3IKZHJpdmVyCj4gc3BlY2lmaWMgdXNlICovCj4gLSNkZWZpbmUg QkxfQ09SRV9EUklWRVIzCQkoMSA8PCAyOSkJLyogcmVzZXJ2ZWQgZm9yCmRyaXZlcgo+IHNwZWNp ZmljIHVzZSAqLwo+IC0jZGVmaW5lIEJMX0NPUkVfRFJJVkVSMgkJKDEgPDwgMzApCS8qIHJlc2Vy dmVkIGZvcgpkcml2ZXIKPiBzcGVjaWZpYyB1c2UgKi8KPiAgI2RlZmluZSBCTF9DT1JFX0RSSVZF UjEJCSgxIDw8IDMxKQkvKiByZXNlcnZlZCBmb3IKZHJpdmVyCj4gc3BlY2lmaWMgdXNlICovCj4g Cj4gIH07Cj4gLS0KPiAyLjE3LjAKCgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fX19fXwpkcmktZGV2ZWwgbWFpbGluZyBsaXN0CmRyaS1kZXZlbEBsaXN0cy5mcmVl ZGVza3RvcC5vcmcKaHR0cHM6Ly9saXN0cy5mcmVlZGVza3RvcC5vcmcvbWFpbG1hbi9saXN0aW5m by9kcmktZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756405AbeDYTmT (ORCPT ); Wed, 25 Apr 2018 15:42:19 -0400 Received: from mail-qk0-f195.google.com ([209.85.220.195]:35615 "EHLO mail-qk0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751296AbeDYTmR (ORCPT ); Wed, 25 Apr 2018 15:42:17 -0400 X-Google-Smtp-Source: AB8JxZrhPsErDTUtZk0XbXWCwBYlH2RhL3UCbz/6ceEkYAT/SAd3U6lpLUSgb6TcuZ3Jz4UBjPYTxw== From: "Jingoo Han" To: "'Daniel Vetter'" , "'DRI Development'" , "'LKML'" Cc: "'Lee Jones'" , "'Daniel Thompson'" , "'Meghana Madhyastha'" , "'Daniel Vetter'" References: <20180425174253.4616-1-daniel.vetter@ffwll.ch> In-Reply-To: <20180425174253.4616-1-daniel.vetter@ffwll.ch> Subject: Re: [PATCH 1/6] backlight: Nuke unused backlight.props.state states Date: Wed, 25 Apr 2018 15:42:15 -0400 Message-ID: <000001d3dccd$83e2c680$8ba85380$@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 16.0 Content-language: en-us Thread-Index: AQKYOvWw68i4qsBoV9wH2Dzil6RYcqKJJL1w Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wednesday, April 25, 2018 1:43 PM, Daniel Vetter wrote: > > The backlight power state handling is supremely confusing. We have: > - props.power, using FB_BLANK_* defines > - props.fb_blank, using the same, but deprecated int favour of > props.state > - props.state, using the BL_CORE_* defines > - and finally a bunch of backlight drivers treat brightness == 0 as > off. But of course not all of them. > > This is way too much confusion to fix in a simple patch, but at least > prevent more hilarity from spreading by removing the unused BL_CORE_* > defines. I have no idea why exactly anyone would need that. > > Wrt the ideal state, we really just want a boolean state. The 4 power > saving states that the fbdev subsystem uses are overkill in todays hw > (this was only relevant for VGA and similar analog circuits like > TV-out), the new drm atomic modeset api simplified even the uapi to a > simple bool. And there was never a valid technical reason to have the > intermediate fbdev power states for backlights (those really only can > be either off or on). > > Cleanup motivated by Meghana's questions about all this. > > Cc: Lee Jones > Cc: Daniel Thompson > Cc: Jingoo Han > Cc: Meghana Madhyastha > Acked-by: Daniel Thompson > Signed-off-by: Daniel Vetter Acked-by: Jingoo Han I really love this patch! Good job! Thank you. Best regards, Jingoo Han > --- > include/linux/backlight.h | 3 --- > 1 file changed, 3 deletions(-) > > diff --git a/include/linux/backlight.h b/include/linux/backlight.h > index 2baab6f3861d..1db67662bfcb 100644 > --- a/include/linux/backlight.h > +++ b/include/linux/backlight.h > @@ -84,9 +84,6 @@ struct backlight_properties { > > #define BL_CORE_SUSPENDED (1 << 0) /* backlight is suspended */ > #define BL_CORE_FBBLANK (1 << 1) /* backlight is under an fb > blank event */ > -#define BL_CORE_DRIVER4 (1 << 28) /* reserved for driver > specific use */ > -#define BL_CORE_DRIVER3 (1 << 29) /* reserved for driver > specific use */ > -#define BL_CORE_DRIVER2 (1 << 30) /* reserved for driver > specific use */ > #define BL_CORE_DRIVER1 (1 << 31) /* reserved for driver > specific use */ > > }; > -- > 2.17.0