Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757534Ab1DHQLS (ORCPT ); Fri, 8 Apr 2011 12:11:18 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:51979 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757438Ab1DHQLR (ORCPT ); Fri, 8 Apr 2011 12:11:17 -0400 Date: Fri, 8 Apr 2011 17:11:13 +0100 From: Jamie Iles To: Anton Vorontsov Cc: Jamie Iles , linux-kernel@vger.kernel.org, linux@arm.linux.org.uk, tglx@linutronix.de, grant.likely@secretlab.ca, arnd@arndb.de, nico@fluxnic.net Subject: Re: [PATCHv2 6/7] basic_mmio_gpio: support different input/output registers Message-ID: <20110408161113.GG2933@pulham.picochip.com> References: <1302272211-30242-1-git-send-email-jamie@jamieiles.com> <1302272211-30242-7-git-send-email-jamie@jamieiles.com> <20110408144628.GC25237@oksana.dev.rtsoft.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110408144628.GC25237@oksana.dev.rtsoft.ru> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4549 Lines: 143 On Fri, Apr 08, 2011 at 06:46:28PM +0400, Anton Vorontsov wrote: > On Fri, Apr 08, 2011 at 03:16:50PM +0100, Jamie Iles wrote: > > Some controllers have separate input and output registers. For these > > controllers, allow a register named "in" to be used for reading the > > value of a GPIO pin. > > > > Signed-off-by: Jamie Iles > > Acked-by: Anton Vorontsov > > Cc: Grant Likely > > --- > > drivers/gpio/basic_mmio_gpio.c | 31 +++++++++++++++++++++++++++++-- > > 1 files changed, 29 insertions(+), 2 deletions(-) > > > > diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c > > index 9be1867..ed4b0c6 100644 > > --- a/drivers/gpio/basic_mmio_gpio.c > > +++ b/drivers/gpio/basic_mmio_gpio.c > > @@ -70,6 +70,7 @@ struct bgpio_chip { > > void __iomem *reg_dat; > > void __iomem *reg_set; > > void __iomem *reg_clr; > > + void __iomem *reg_in; > > Btw, I wonder if it makes sense (and more logical) for separate output/ > input registers case to use "reg_dat" for 'input' and 'reg_set' for > output? Sounds like a good idea. Something like this? Jamie diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c index 054fbee..fc3826a 100644 --- a/drivers/gpio/basic_mmio_gpio.c +++ b/drivers/gpio/basic_mmio_gpio.c @@ -185,6 +185,24 @@ static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio, bgc->write_reg(bgc->reg_clr, mask); } +static void bgpio_set_set(struct gpio_chip *gc, unsigned int gpio, int val) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + unsigned long mask = bgc->pin2mask(bgc, gpio); + unsigned long flags; + + spin_lock_irqsave(&bgc->lock, flags); + + if (val) + bgc->data |= mask; + else + bgc->data &= ~mask; + + bgc->write_reg(bgc->reg_set, bgc->data); + + spin_unlock_irqrestore(&bgc->lock, flags); +} + static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio) { return 0; @@ -245,10 +263,12 @@ static int bgpio_setup_accessors(struct platform_device *pdev, /* * Create the device and allocate the resources. For setting GPIO's there are - * two supported configurations: + * three supported configurations: * - * - single output register resource (named "dat"). + * - single input/output register resource (named "dat"). * - set/clear pair (named "set" and "clr"). + * - single output register resource and single input resource ("set" and + * dat"). * * For the single output register, this drives a 1 by setting a bit and a zero * by clearing a bit. For the set clr pair, this drives a 1 by setting a bit @@ -260,6 +280,15 @@ static int bgpio_setup_io(struct platform_device *pdev, { struct resource *res_set; struct resource *res_clr; + struct resource *res_dat; + + res_dat = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat"); + if (!res_dat) + return -EINVAL; + + bgc->reg_dat = bgpio_request_and_map(&pdev->dev, res_dat); + if (!bgc->reg_dat) + return -ENOMEM; res_set = platform_get_resource_byname(pdev, IORESOURCE_MEM, "set"); res_clr = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clr"); @@ -274,12 +303,22 @@ static int bgpio_setup_io(struct platform_device *pdev, return -ENOMEM; bgc->gc.set = bgpio_set_with_clear; - } else if (res_set || res_clr) { - return -EINVAL; + } else if (res_set && !res_clr) { + if (resource_size(res_set) != resource_size(res_dat) || + resource_size(res_set) != bgc->bits / 8) + return -EINVAL; + + bgc->reg_set = bgpio_request_and_map(&pdev->dev, res_set); + if (!bgc->reg_set) + return -ENOMEM; + + bgc->gc.set = bgpio_set_set; } else { bgc->gc.set = bgpio_set; } + bgc->gc.get = bgpio_get; + return 0; } @@ -311,10 +350,6 @@ static int __devinit bgpio_probe(struct platform_device *pdev) if (!bgc) return -ENOMEM; - bgc->reg_dat = bgpio_request_and_map(dev, res_dat); - if (!bgc->reg_dat) - return -ENOMEM; - if (pdata) { bgc->gc.base = pdata->base; if (pdata->ngpio > 0) @@ -338,7 +373,6 @@ static int __devinit bgpio_probe(struct platform_device *pdev) bgc->gc.ngpio = ngpio; bgc->gc.direction_input = bgpio_dir_in; bgc->gc.direction_output = bgpio_dir_out; - bgc->gc.get = bgpio_get; bgc->gc.dev = dev; bgc->gc.label = dev_name(dev); -- 1.7.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/