From mboxrd@z Thu Jan 1 00:00:00 1970 From: Juergen Beisert Date: Thu, 10 Feb 2011 09:46:33 +0000 Subject: Re: [PATCH 1/2] video: Add i.MX23/28 framebuffer driver Message-Id: <201102101046.33994.jbe@pengutronix.de> List-Id: References: <1297257651-8002-1-git-send-email-s.hauer@pengutronix.de> <1297257651-8002-2-git-send-email-s.hauer@pengutronix.de> <09EC74FE2C9E8444BF2FF67BD36E1D69167919@039-SN1MPN1-003.039d.mgd.msft.net> In-Reply-To: <09EC74FE2C9E8444BF2FF67BD36E1D69167919@039-SN1MPN1-003.039d.mgd.msft.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org Li Frank-B20596 wrote: > > + > > + /* if it was disabled, re-enable the mode again */ > > + reg = readl(host->base + CTRL); > > + reg |= CTRL_DOTCLK_MODE; > > + writel(reg, host->base + CTRL); > > writel(CTRL_DOTCLK_MODE, host->base + CTRL_SET) > CTRL_SET is CTRL+0x4 > SET and CLR register is easier than Read and write back. But you must always check, if the register really has such a SET and CLEAR feature. Not all registers have this feature... But in this case you are right. But I would prefer: #define SET 4 #define CLEAR 8 [...] writel(CTRL_DOTCLK_MODE, host->base + CTRL + SET) :-) Regards, Juergen -- Pengutronix e.K. | Juergen Beisert | Linux Solutions for Science and Industry | Phone: +49-8766-939 228 | Vertretung Sued/Muenchen, Germany | Fax: +49-5121-206917-5555 | Amtsgericht Hildesheim, HRA 2686 | http://www.pengutronix.de/ |