On Mon, Jul 27, 2020 at 10:44:57AM +0000, Codrin.Ciubotariu@xxxxxxxxxxxxx wrote: > On 24.07.2020 23:52, Russell King - ARM Linux admin wrote: > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe > > > > On Fri, Jul 24, 2020 at 09:39:13PM +0200, Wolfram Sang wrote: > >> On Sun, Jul 05, 2020 at 11:19:18PM +0200, Wolfram Sang wrote: > >>> > >>>> +- pinctrl > >>>> + add extra pinctrl to configure SCL/SDA pins to GPIO function for bus > >>>> + recovery, call it "gpio" or "recovery" state > >>> > >>> I think we should stick with "gpio" only. That is what at91 and imx have > >>> in their bindings. pxa uses "recovery" as a pinctrl state name but I > >>> can't find any further use or documentation of that. PXA is not fully > >>> converted to the best of my knowledge, so maybe it is no problem for PXA > >>> to switch to "gpio", too? We should ask Russell King (cced). > > > > Fully converted to what? The generic handling where the i2c core layer > > handles everything to do with recovery, including the switch between > > modes? > > > > i2c-pxa _intentionally_ carefully handles the switch between i2c mode and > > GPIO mode, and I don't see a generic driver doing that to avoid causing > > any additional glitches on the bus. Given the use case that this recovery > > is targetted at, avoiding glitches is very important to keep. > > Why is it not possbile to handle glitches in a generic way? I guess it > depends on the pinctl, but we could treat a worst-case scenario to > assure the switch between states is done properly. Please look at how i2c-pxa switches between the two, and decide whether the generic implementation can do the same. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!
