From: swarren@wwwdotorg.org (Stephen Warren) Date: Tue, 16 Jul 2013 09:47:02 -0600 Subject: [PATCH v8] reset: Add driver for gpio-controlled reset pins In-Reply-To: <20130716065130.GB30067@S2101-09.ap.freescale.net> References: <1369904940-716-1-git-send-email-p.zabel@pengutronix.de> <20130716015038.GD28375@S2101-09.ap.freescale.net> <20130716065130.GB30067@S2101-09.ap.freescale.net> Message-ID: <51E56AF6.30506@wwwdotorg.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 07/16/2013 12:51 AM, Shawn Guo wrote: > On Tue, Jul 16, 2013 at 09:50:42AM +0800, Shawn Guo wrote: >> Hi Philipp, >> >> On Thu, May 30, 2013 at 11:09:00AM +0200, Philipp Zabel wrote: >>> This driver implements a reset controller device that toggle a gpio >>> connected to a reset pin of a peripheral IC. The delay between assertion >>> and de-assertion of the reset signal can be configured via device tree. >>> >>> Signed-off-by: Philipp Zabel >>> Reviewed-by: Stephen Warren >> >> I see this patch is very useful, as GPIOs are widely used to reset >> components/devices on board. But I do not find the patch in v3.11-rc1. >> What's your plan about it? >> >> Also, I'm wondering if we should register the driver a little bit >> early. Please see the following patch. If it makes sense to you, >> I can send the patch to you, or you can just quash it into yours. > > And here is another change request. > diff --git a/drivers/reset/gpio-reset.c b/drivers/reset/gpio-reset.c > - gpio_set_value(drvdata->gpio, value); > + if (gpio_cansleep(drvdata->gpio)) > + gpio_set_value_cansleep(drvdata->gpio, value); > + else > + gpio_set_value(drvdata->gpio, value); That's not right. Calling gpio_set_value() v.s. gpio_set_value_cansleep() should be based on the properties of the calling context, not the GPIO being controlled. In other words, if it's permissible to call gpio_set_value_cansleep() at this point in the code, simply always call that, and remove the conditional logic.