From mboxrd@z Thu Jan 1 00:00:00 1970 From: wsa@the-dreams.de (Wolfram Sang) Date: Tue, 7 Jul 2015 16:13:12 +0200 Subject: [PATCH v2 5/5] i2c: davinci: use ICPFUNC to toggle I2C as gpio for bus recovery In-Reply-To: <20150707134852.GE9671@pengutronix.de> References: <1417010393-30598-1-git-send-email-grygorii.strashko@ti.com> <1417010393-30598-6-git-send-email-grygorii.strashko@ti.com> <20141126160407.GN4431@pengutronix.de> <5476085B.40009@ti.com> <1436276269.3344.94.camel@pengutronix.de> <20150707134852.GE9671@pengutronix.de> Message-ID: <20150707141312.GC3411@katana> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Jul 07, 2015 at 03:48:52PM +0200, Uwe Kleine-K?nig wrote: > Hello, > > On Tue, Jul 07, 2015 at 03:37:49PM +0200, Jan L?bbe wrote: > > On Mi, 2014-11-26 at 19:05 +0200, Grygorii Strashko wrote: > > > On 11/26/2014 06:04 PM, Uwe Kleine-K?nig wrote: > > > > On Wed, Nov 26, 2014 at 03:59:53PM +0200, Grygorii Strashko wrote: > > > >> Having a board where the I2C bus locks up occasionally made it clear > > > >> that the bus recovery in the i2c-davinci driver will only work on > > > >> some boards, because on regular boards, this will only toggle GPIO > > > >> lines that aren't muxed to the actual pins. > > > >> > > > >> The I2C controller on SoCs like da850 (and da830), Keystone 2 has the > > > >> built-in capability to bit-bang its lines by using the ICPFUNC registers > > > >> of the i2c controller. > > > >> Implement the suggested procedure by toggling SCL and checking SDA using > > > >> the ICPFUNC registers of the I2C controller when present. Allow platforms > > > >> to indicate the presence of the ICPFUNC registers with a has_pfunc platform > > > >> data flag and add optional DT property "ti,has-pfunc" to indicate > > > >> the same in DT. > > > > On what does it depend if this pfunc stuff works or not? Only the SoC, > > > > or also on some board specific properties? > > > > > > SoC / set of SoCs. Also, similar feature is supported by OMAP and AM335x/AM437x SoCs > > > using I2C_SYSTEST register. > > > > > > > Given the former using the > > > > compatible string to detect its availability would be better. (In this > > > > case also sorry, didn't consider this case when requesting the property > > > > in the last round.) > > > > I only stumbled across this after it was merged, with the additional > I also wonder how it came to the Reviewed-by tag for me. The last thing > that I said about the patch was "On what does it depend if this pfunc > stuff works or not? Only the SoC, or also on some board specific > properties?" (see above) and "the patch looks ok". IMHO this hardly > justifies to add the Reviewed-by tag for the next round. :-( That needs to be discussed with Grygorii. I can't verify the correctness of tags for every patch, although I do try to keep an eye on it... -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: