From mboxrd@z Thu Jan 1 00:00:00 1970 From: linux@roeck-us.net (Guenter Roeck) Date: Thu, 13 Sep 2018 08:57:03 -0700 Subject: [PATCH i2c-next v6] i2c: aspeed: Handle master/slave combined irq events properly In-Reply-To: References: <20180911233302.GA18799@roeck-us.net> <5698ca34-14c9-8d05-c4e6-5acf85ff9d14@linux.intel.com> <20180912013449.GA12612@roeck-us.net> <7fd98646-fb5a-be4d-ce37-84b74e0fa8b3@linux.intel.com> <20180912195844.GA6893@roeck-us.net> <20180912203059.GA18201@roeck-us.net> <3f86e75f-1502-eae8-0633-d087937111c8@roeck-us.net> Message-ID: <20180913155703.GA22605@roeck-us.net> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Sep 13, 2018 at 05:48:59PM +0200, C?dric Le Goater wrote: > On 09/13/2018 03:33 PM, Guenter Roeck wrote: [ ... ] > >>> ? /* > >>> ?? * The state machine needs some refinement. It is only used to track > >>> ?? * invalid STOP commands for the moment. > >>> @@ -188,7 +215,7 @@ static void aspeed_i2c_bus_handle_cmd(AspeedI2CBus *bus, uint64_t value) > >>> ? { > >>> ????? bus->cmd &= ~0xFFFF; > >>> ????? bus->cmd |= value & 0xFFFF; > >>> -??? bus->intr_status = 0;> +??? bus->intr_status &= I2CD_INTR_RX_DONE; > >> > >> it deserves a comment to understand which scenario we are trying to handle. > >> ?? > > > > Ok. FWIW, I wonder if intr_status should be touched here in the first place, > > but I neither have the hardware nor a datasheet, so I don't know if any bits > > are auto-cleared. > > I just pushed a patch on my branch with some more explanation : > > https://github.com/legoater/qemu/commits/aspeed-3.1 > That seems to suggest that none of the status bits auto-clears, and that the above code clearing intr_status should be removed entirely. Am I missing something ? Thanks, Guenter