From mboxrd@z Thu Jan 1 00:00:00 1970 From: Huang Tao Subject: Re: [PATCH 2/2] ASoC: add driver for Rockchip RK3xxx I2S controller Date: Wed, 02 Jul 2014 09:01:49 +0800 Message-ID: <53B359FD.3080809@rock-chips.com> References: <1404203860-30712-1-git-send-email-xjq@rock-chips.com> <1404204458-30881-1-git-send-email-xjq@rock-chips.com> <20140701170747.GA15028@sirena.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Received: from regular1.263xmail.com (regular1.263xmail.com [211.150.99.131]) by alsa0.perex.cz (Postfix) with ESMTP id BB3F2265150 for ; Wed, 2 Jul 2014 03:01:56 +0200 (CEST) In-Reply-To: <20140701170747.GA15028@sirena.org.uk> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: alsa-devel-bounces@alsa-project.org Sender: alsa-devel-bounces@alsa-project.org To: Mark Brown Cc: yzq@rock-chips.com, devicetree@vger.kernel.org, alsa-devel@alsa-project.org, heiko@sntech.de, tiwai@suse.de, linux-kernel@vger.kernel.org, zhangqing@rock-chips.com, lgirdwood@gmail.com, robh+dt@kernel.org, kever.yang@rock-chips.com, zyw@rock-chips.com, jianqun , kfx@rock-chips.com, grant.likely@linaro.org, cf@rock-chips.com, hj@rock-chips.com, zhenfu.fang@rock-chips.com List-Id: alsa-devel@alsa-project.org SGksIE1hcms6Cgrkuo4gMjAxNOW5tDA35pyIMDLml6UgMDE6MDcsIE1hcmsgQnJvd24g5YaZ6YGT Ogo+PiArc3RhdGljIGlubGluZSB2b2lkIGkyc193cml0ZWwoc3RydWN0IHJrX2kyc19kZXYgKmky cywgdTMyIHZhbHVlLAo+PiA+ICsJCQkgICAgICB1bnNpZ25lZCBpbnQgb2Zmc2V0KQo+PiA+ICt7 Cj4+ID4gKwl3cml0ZWxfcmVsYXhlZCh2YWx1ZSwgaTJzLT5yZWdzICsgb2Zmc2V0KTsKPj4gPiAr fQo+PiA+ICsKPj4gPiArc3RhdGljIGlubGluZSB1MzIgaTJzX3JlYWRsKHN0cnVjdCBya19pMnNf ZGV2ICppMnMsIHVuc2lnbmVkIGludCBvZmZzZXQpCj4+ID4gK3sKPj4gPiArCXJldHVybiByZWFk bF9yZWxheGVkKGkycy0+cmVncyArIG9mZnNldCk7Cj4+ID4gK30KPiBQZXJoYXBzIHVzZSByZWdt YXA/ICBUaGUgbWFpbiBhZHZhbnRhZ2Ugd291bGQgYmUgdGhlIGRlYnVnCj4gaW5mcmFzdHJ1Y3R1 cmUsIHRob3VnaCB5b3UgY291bGQgYWxzbyB1c2UgX3VwZGF0ZV9iaXRzKCkgdG8gcmVkdWNlIHRo ZQo+IGFtb3VudCBvZiB0aW1lIHNwZW50IGxvY2tlZC4KPgpBcmUgeW91IHN1cmU/IFRoaXMgaXMg YSBJMlMgZHJpdmVyLCB3ZSBjYW4gd3JpdGUgdGhlIHJlZ2lzdGVyIGRpcmVjdGx5LApkbyBub3Qg dGhyb3VnaCBJMkMgb3IgU1BJIGJ1cy4KV3JpdGUgYSByZWdpc3RlciBpcyBvbmx5IGEgZmV3IGlu c3RydWN0aW9ucyBvbiBBUk0sIGJ1dCB3cml0ZSB0aHJvdWdoCnJlZ21hcCwgaXQgbWF5IHRha2Ug YSBsb25nIHBhdGguCkkgdGhpbmsgaXQgd2lsbCBqdXN0IGNvbnN1bWUgQ1BVIHBvd2VyIGFuZCBt YWtlIHRoZSB3aG9sZSB0aGluZyBtb3JlCmNvbXBsZXguCkNvdWxkIHlvdSB0ZWxsIG1lIHdoYXQg YmVuZWZpdHMgd2UgY2FuIGdldCBpZiB1c2UgcmVnbWFwPyBPciBzb21ldGhpbmcgSQpqdXN0IG1p c3Npbmc/CgpfX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fXwpB bHNhLWRldmVsIG1haWxpbmcgbGlzdApBbHNhLWRldmVsQGFsc2EtcHJvamVjdC5vcmcKaHR0cDov L21haWxtYW4uYWxzYS1wcm9qZWN0Lm9yZy9tYWlsbWFuL2xpc3RpbmZvL2Fsc2EtZGV2ZWwK From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965266AbaGBBKK (ORCPT ); Tue, 1 Jul 2014 21:10:10 -0400 Received: from regular2.263xmail.com ([211.157.152.4]:43135 "EHLO regular2.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965233AbaGBBKG (ORCPT ); Tue, 1 Jul 2014 21:10:06 -0400 X-Greylist: delayed 467 seconds by postgrey-1.27 at vger.kernel.org; Tue, 01 Jul 2014 21:10:05 EDT X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-ABS-CHECKED: 4 X-KSVirus-check: 0 X-RL-SENDER: huangtao@rock-chips.com X-FST-TO: broonie@kernel.org X-SENDER-IP: 127.0.0.1 X-LOGIN-NAME: huangtao@rock-chips.com X-UNIQUE-TAG: <9790f353cdf8195cdadc56e7318f3e83> X-ATTACHMENT-NUM: 0 X-DNS-TYPE: 1 Message-ID: <53B359FD.3080809@rock-chips.com> Date: Wed, 02 Jul 2014 09:01:49 +0800 From: Huang Tao User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Mark Brown CC: jianqun , heiko@sntech.de, lgirdwood@gmail.com, perex@perex.cz, tiwai@suse.de, grant.likely@linaro.org, robh+dt@kernel.org, linux-kernel@vger.kernel.org, alsa-devel@alsa-project.org, devicetree@vger.kernel.org, zhangqing@rock-chips.com, hj@rock-chips.com, kever.yang@rock-chips.com, zyw@rock-chips.com, yzq@rock-chips.com, zhenfu.fang@rock-chips.com, cf@rock-chips.com, kfx@rock-chips.com Subject: Re: [PATCH 2/2] ASoC: add driver for Rockchip RK3xxx I2S controller References: <1404203860-30712-1-git-send-email-xjq@rock-chips.com> <1404204458-30881-1-git-send-email-xjq@rock-chips.com> <20140701170747.GA15028@sirena.org.uk> In-Reply-To: <20140701170747.GA15028@sirena.org.uk> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Mark: 于 2014年07月02日 01:07, Mark Brown 写道: >> +static inline void i2s_writel(struct rk_i2s_dev *i2s, u32 value, >> > + unsigned int offset) >> > +{ >> > + writel_relaxed(value, i2s->regs + offset); >> > +} >> > + >> > +static inline u32 i2s_readl(struct rk_i2s_dev *i2s, unsigned int offset) >> > +{ >> > + return readl_relaxed(i2s->regs + offset); >> > +} > Perhaps use regmap? The main advantage would be the debug > infrastructure, though you could also use _update_bits() to reduce the > amount of time spent locked. > Are you sure? This is a I2S driver, we can write the register directly, do not through I2C or SPI bus. Write a register is only a few instructions on ARM, but write through regmap, it may take a long path. I think it will just consume CPU power and make the whole thing more complex. Could you tell me what benefits we can get if use regmap? Or something I just missing?