From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mathias Nyman Subject: Re: [PATCH 1/1] gpio: add Lynxpoint chipset gpio driver. Date: Tue, 11 Dec 2012 13:40:51 +0200 Message-ID: <50C71BC3.2090006@linux.intel.com> References: <1354888899-21907-1-git-send-email-mathias.nyman@linux.intel.com> <1354888899-21907-2-git-send-email-mathias.nyman@linux.intel.com> <20121210230749.7820F3E081F@localhost> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mga14.intel.com ([143.182.124.37]:34685 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752559Ab2LKLia (ORCPT ); Tue, 11 Dec 2012 06:38:30 -0500 In-Reply-To: <20121210230749.7820F3E081F@localhost> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Grant Likely Cc: linus.walleij@linaro.org, mika.westerberg@linux.intel.com, rafael.j.wysocki@intel.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org On 12/11/2012 01:07 AM, Grant Likely wrote: > On Fri, 7 Dec 2012 16:01:39 +0200, Mathias Nyman wrote: >> Add gpio support for Intel Lynxpoint chipset. >> Lynxpoint supports 94 gpio pins which can generate interrupts. >> Driver will fail requests for pins that are marked as owned by ACPI, or >> set in an alternate mode (non-gpio). >> >> Signed-off-by: Mathias Nyman >> --- >> +static void lp_gpio_set(struct gpio_chip *chip, unsigned gpio, int value) >> +{ >> + struct lp_gpio *lg = container_of(chip, struct lp_gpio, chip); >> + unsigned long reg = gpio_reg(chip, gpio, LP_CONFIG1); >> + unsigned long flags; >> + >> + spin_lock_irqsave(&lg->lock, flags); >> + >> + if (value) >> + outl(inl(reg) | OUT_LVL_BIT, reg); >> + else >> + outl(inl(reg)& ~OUT_LVL_BIT, reg); >> + >> + spin_unlock_irqrestore(&lg->lock, flags); >> +} > > A *lot* of drivers implement their own GPIO ops like this, and they all > end up looking the same. Please take a look at > drivers/gpio/gpio-generic.c and see if you can use the stock operations > provided there. > > g. > Look quite similar but turns out the only potential generic ones which could be used are the bgpio_set() and bgpio_get() funtions. Using them would require custom pin2mask, write_reg, read_reg, etc functions. bgpio_set_direction I guess using gpio-generic code fits memory mapped devices better. Trying to use it for io port devices would require a lot of code mangling. -Mathias