From mboxrd@z Thu Jan 1 00:00:00 1970 From: Finn Thain Subject: Re: [PATCH 01/16] pmac_zilog: fix unexpected irq Date: Fri, 25 Nov 2011 14:15:10 +1100 (EST) Message-ID: References: <20111023141108.856998818@telegraphics.com.au> <20111023141115.208699274@telegraphics.com.au> <20111124145624.24438832@lxorguk.ukuu.org.uk> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: In-Reply-To: <20111124145624.24438832@lxorguk.ukuu.org.uk> Sender: linux-m68k-owner@vger.kernel.org To: Alan Cox Cc: Benjamin Herrenschmidt , linux-serial@vger.kernel.org, linux-m68k@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, Geert Uytterhoeven List-Id: linux-serial@vger.kernel.org On Thu, 24 Nov 2011, Alan Cox wrote: > Given the change should work for all hardware do we really need the > ifdefs. Far better I would have thought to just change it so we don't > have to maintain what is effectively two versions of the code between > now and 2038. I agree. > > So no ack from me yet - I'd like to understand the ifdef decision first. Removing ifdefs makes the changes more invasive and the suspend/resume code then has to be addressed, which I've avoided. The suspend/resume code path can't be tested on m68k macs and the common code paths I can't easily test on a powermac. This patch should not be needed because the chip reset shouldn't leave the tx and rx interrupts enabled. Those interrupts are explicitly enabled only after request_irq(), so patching the master interrupt enable behaviour should be redundant. But that's not the case in practice. The chip reset code is already messy. I was inclined towards ifdefs and reluctant to share more code after practical experience suggested possible differences in the SCC/ESCC devices. I guess I was hoping that the powermac maintainers might prefer ifdefs to increased risk of destabilising the driver on powermacs... But a more invasive patch would make for better code. I will see if I can borrow a suitable PCI PowerMac. Finn > Otherwise it looks sensible. > > Alan