From mboxrd@z Thu Jan 1 00:00:00 1970 From: Caesar Wang Subject: Re: [PATCH] i2c: rk3x: Increase wait timeout to 1 second Date: Fri, 01 May 2015 11:42:53 +0800 Message-ID: <5542F63D.3000402@163.com> References: <1430430247-9632-1-git-send-email-dianders@chromium.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1430430247-9632-1-git-send-email-dianders@chromium.org> Sender: linux-kernel-owner@vger.kernel.org To: Doug Anderson , Wolfram Sang Cc: Addy Ke , Dmitry Torokhov , Heiko Stuebner , Max Schwarz , linux-kernel@vger.kernel.org, linux-rockchip@lists.infradead.org, linux-i2c@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-i2c@vger.kernel.org =E5=9C=A8 2015=E5=B9=B405=E6=9C=8801=E6=97=A5 05:44, Doug Anderson =E5=86= =99=E9=81=93: > While it's not sensible for an i2c command to _actually_ need more > than 200ms to complete, let's increase the timeout anyway. Why? It > turns out that if you've got a large number of printks going out to a > serial console, interrupts on a CPU can be disabled for hundreds of > milliseconds. That's not a great situation to be in to start with > (maybe we should put a cap in vprintk_emit()) but it's pretty annoyin= g > to start seeing unexplained i2c timeouts. > > A normal system shouldn't see i2c timeouts anyway, so increasing the > timeout should help people debugging without hurting other people > excessively. > > Signed-off-by: Doug Anderson > --- > drivers/i2c/busses/i2c-rk3x.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-r= k3x.c > index 019d542..72e97e30 100644 > --- a/drivers/i2c/busses/i2c-rk3x.c > +++ b/drivers/i2c/busses/i2c-rk3x.c > @@ -72,7 +72,7 @@ enum { > #define REG_INT_ALL 0x7f > =20 > /* Constants */ > -#define WAIT_TIMEOUT 200 /* ms */ > +#define WAIT_TIMEOUT 1000 /* ms */ Yeah,verified on veyron device. Tested-by: Caesar Wang Thanks. Caesar > #define DEFAULT_SCL_RATE (100 * 1000) /* Hz */ > =20 > enum rk3x_i2c_state {