From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sascha Hauer Subject: Re: [PATCH 2/4] i2c: imx: only imx1 needs disable delay Date: Thu, 1 Oct 2009 09:26:43 +0200 Message-ID: <20091001072643.GW27039@pengutronix.de> References: <1254359613-21210-1-git-send-email-linuxzsc@gmail.com> <1254359613-21210-2-git-send-email-linuxzsc@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1254359613-21210-2-git-send-email-linuxzsc-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Richard Zhao Cc: kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, w.sang-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org List-Id: linux-i2c@vger.kernel.org On Thu, Oct 01, 2009 at 09:13:31AM +0800, Richard Zhao wrote: > check cpu_is_mx1() when set disable_delay. > > Signed-off-by: Richard Zhao > > diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c > index 156cc95..c1e541c 100644 > --- a/drivers/i2c/busses/i2c-imx.c > +++ b/drivers/i2c/busses/i2c-imx.c > @@ -254,14 +254,16 @@ static void __init i2c_imx_set_clk(struct imx_i2c_struct *i2c_imx, > /* Write divider value to register */ > writeb(i2c_clk_div[i][1], i2c_imx->base + IMX_I2C_IFDR); > > - /* > - * There dummy delay is calculated. > - * It should be about one I2C clock period long. > - * This delay is used in I2C bus disable function > - * to fix chip hardware bug. > - */ > - i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0] > - + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2); > + if (cpu_is_mx1()) { > + /* > + * There dummy delay is calculated. > + * It should be about one I2C clock period long. > + * This delay is used in I2C bus disable function > + * to fix chip hardware bug. > + */ > + i2c_imx->disable_delay = (500000U * i2c_clk_div[i][0] > + + (i2c_clk_rate / 2) - 1) / (i2c_clk_rate / 2); > + } I think you should put the udelay(i2c_imx->disable_delay) in cpu_is_mx1() rather than the calculation. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |