From mboxrd@z Thu Jan 1 00:00:00 1970 From: York Sun Subject: Re: Why isn't IRQ shared for i2c-ocore Date: Thu, 7 May 2015 07:46:29 -0700 Message-ID: <554B7AC5.5040401@freescale.com> References: <55304D8E.8070204@freescale.com> <55312AF7.7070504@freescale.com> <20150420064231.GE3447@x1> <55352839.70905@freescale.com> <20150420181651.GF3447@x1> <5535460B.2060309@freescale.com> <20150421073534.GK3447@x1> <554A8A8B.1020703@freescale.com> <20150507070149.GB3400@x1> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150507070149.GB3400@x1> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lee Jones Cc: Julia.Lawall-L2FTfq7BK8M@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, wolfram-z923LK4zBo2bacvFa/9K2g@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org On 05/07/2015 12:01 AM, Lee Jones wrote: >> I have a follow up question regarding interrupt. I see many I2C bus drivers >> request interrupt with flag = 0. Why not using IRQF_SHARED? > > Probably because that particular IRQ is only used by the I2C > Controller. I'm not exactly sure that you're getting at? Why do you > think it should be shared? You should only flag it as shared if it > is. I am working on a driver for multifunction card with open core I2C controller. The interrupt is shared between I2C and other controller. > >> I understand the performance concern. If there is any other reason, I want to >> know about it before I go too far on my driver. > > This sort of stuff is trivial to fix and shouldn't stand in the way > of you writing and submitting v1 of your driver. > It is trivial to fix. I just want to know if there is any reason the interrupt wasn't shared. Seems not. York