From mboxrd@z Thu Jan 1 00:00:00 1970 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= Subject: Re: [PATCH v4 2/3] i2c: iproc: Add Broadcom iProc I2C Driver Date: Sat, 17 Jan 2015 17:01:13 +0100 Message-ID: <20150117160113.GA22880@pengutronix.de> References: <1421274213-3544-1-git-send-email-rjui@broadcom.com> <1421274213-3544-3-git-send-email-rjui@broadcom.com> <20150115084119.GN22880@pengutronix.de> <54B98C18.4080807@broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Content-Disposition: inline In-Reply-To: <54B98C18.4080807-dY08KVG/lbpWk0Htik3J/w@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Ray Jui Cc: Wolfram Sang , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Grant Likely , Christian Daudt , Matt Porter , Florian Fainelli , Russell King , Scott Branden , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, bcm-kernel-feedback-list-dY08KVG/lbpWk0Htik3J/w@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Hello, On Fri, Jan 16, 2015 at 02:09:28PM -0800, Ray Jui wrote: > On 1/15/2015 12:41 AM, Uwe Kleine-K=F6nig wrote: > > On Wed, Jan 14, 2015 at 02:23:32PM -0800, Ray Jui wrote: > >> + */ > >> + val =3D 1 << M_CMD_START_BUSY_SHIFT; > >> + if (msg->flags & I2C_M_RD) { > >> + val |=3D (M_CMD_PROTOCOL_BLK_RD << M_CMD_PROTOCOL_SHIFT) | > >> + (msg->len << M_CMD_RD_CNT_SHIFT); > >> + } else { > >> + val |=3D (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT); > >> + } > >> + writel(val, iproc_i2c->base + M_CMD_OFFSET); > >> + > >> + time_left =3D wait_for_completion_timeout(&iproc_i2c->done, time= _left); > >=20 > > When the interrupt fires here after the complete timed out and befo= re > > you disable the irq you still throw the result away. > Yes, but then this comes down to the fact that if it has reached the > point that is determined to be a timeout condition in the driver, one > should really treat it as timeout error. In a normal condition, > time_left should never reach zero. I don't agree here. I'm not sure there is a real technical reason, though. But still if you're in a "success after timeout already over" situation it's IMHO better to interpret it as success, not timeout. > >> +static int bcm_iproc_i2c_remove(struct platform_device *pdev) > >> +{ > >> + struct bcm_iproc_i2c_dev *iproc_i2c =3D platform_get_drvdata(pde= v); > >> + > >> + i2c_del_adapter(&iproc_i2c->adapter); > > You need to free the irq before i2c_del_adapter. > >=20 > Yes. Thanks. Change back to use devm_request_irq, and use disable_irq > here before removing the adapter. The more lightweight approach is to set your device's irq-enable register to zero and call synchronize_irq. (For a shared irq calling disable_irq is even wrong here.) Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig = | Industrial Linux Solutions | http://www.pengutronix.de/= |