From mboxrd@z Thu Jan 1 00:00:00 1970 From: bigeasy@linutronix.de (Sebastian Andrzej Siewior) Date: Thu, 02 Jul 2015 17:54:29 +0200 Subject: [PATCH 1/2] gpio: dwapb: Use human understandable gpio numbering. In-Reply-To: <20150702152147.GA10111@localhost.localdomain> References: <5594E9F6.7040701@linutronix.de> <20150702142601.GB9349@localhost.localdomain> <55954B17.3020303@linutronix.de> <20150702152147.GA10111@localhost.localdomain> Message-ID: <55955EB5.4090400@linutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 07/02/2015 05:21 PM, Richard Cochran wrote: > On Thu, Jul 02, 2015 at 04:30:47PM +0200, Sebastian Andrzej Siewior wrote: >> On 07/02/2015 04:26 PM, Richard Cochran wrote: >>> On Thu, Jul 02, 2015 at 09:36:22AM +0200, Sebastian Andrzej Siewior wrote: >>>> If you are in a specific SoC you could do >>>> base = of_alias_get_id(np, "gpio") * num_of_gpio_per_chip >>>> and get consistent numbers / sane. >>> >>> And what about /sys/class/gpio ? >> >> What about it? > > The poor users of that interface cannot use "of_alias_get_id" as you suggest. You do that in the driver. The only problem with that is that the synopsys controller can have between one and four banks and a bank can have 1-32 GPIOs if I remember correctly. That means you can't have a static number of GPIOs like others do. Therefore I think a starting property is the only way and I would prefer a generic one. What confuses me a little: Why is there a snps,nr-gpios property? Doesn't the snps' IP-Core expose this information? > Thanks, > Richard > Sebastian