Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757454Ab3FSTFP (ORCPT ); Wed, 19 Jun 2013 15:05:15 -0400 Received: from mail-ob0-f181.google.com ([209.85.214.181]:65230 "EHLO mail-ob0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757340Ab3FSTFN (ORCPT ); Wed, 19 Jun 2013 15:05:13 -0400 MIME-Version: 1.0 In-Reply-To: <1371202532-14628-8-git-send-email-avinashphilip@ti.com> References: <1371202532-14628-1-git-send-email-avinashphilip@ti.com> <1371202532-14628-8-git-send-email-avinashphilip@ti.com> Date: Wed, 19 Jun 2013 21:05:12 +0200 Message-ID: Subject: Re: [PATCH v2 7/7] ARM: davinci: Start using gpiolib API inplace of inline functions From: Linus Walleij To: Philip Avinash Cc: "Nori, Sekhar" , ext Kevin Hilman , Russell King - ARM Linux , Grant Likely , "linux-arm-kernel@lists.infradead.org" , "davinci-linux-open-source@linux.davincidsp.com" , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2568 Lines: 63 On Fri, Jun 14, 2013 at 11:35 AM, Philip Avinash wrote: > Remove NEED_MACH_GPIO_H config select option for ARCH_DAVINCI to start > use gpiolib interface for davinci platforms. However with this software > latencies for gpio_get/set APIs will affect. Latency has increased by 18 > microsecond with gpiolib API as compared with inline API's. > > Software latency is calculated on da850 EVM for gpio_get_value API by > taking the printk timing for API execution with interrupts disabled. > Experiment has done for inline and gpiolib API interface. > > inline gpio API with interrupt disabled > [ 29.734337] before gpio_get > [ 29.736847] after gpio_get > > Time difference 0.00251 > > gpio library with interrupt disabled > [ 272.876763] before gpio_get > [ 272.879291] after gpio_get > > Time difference 0.002528 > Latency increased by (0.002528 - 0.00251) = 18 microsecond. > > Also being here > - Moved following definitions from mach folder to include directory > struct davinci_gpio_controller > Macro GPIO(x) > inline function __gpio_mask > - Removed GPIO_TYPE_DAVINCI enum definition as GPIO Davinci is converted > to Linux device driver model. > - With removal of select option of NEED_MACH_GPIO_H for ARCH_DAVINCI, > gpio-tnetv107x also start using gpiolib interface. Hence removes > related header files > arch/arm/mach-davinci/include/mach/gpio-davinci.h > arch/arm/mach-davinci/include/mach/gpio.h > > and include linux/platform_data/gpio-davinci.h header file to support > gpio-davinci platform definitions. > > Signed-off-by: Philip Avinash > Signed-off-by: Sekhar Nori > --- > Changes since v1: > - Remove inline GPIO API support for tnetv107x platforms > - Remove gpio header files in mach directory. > - Remove include of gpio header files from mach directory. > - Moved enum davinci_gpio_type to include folder > - Replace __ASM_ARCH_DAVINCI_GPIO_H with __DAVINCI_GPIO_PLATFORM_H Acked-by: Linus Walleij on this as well, and this whole 7-patch series. For sure things look better after this series than before it, even if there may be details I think need to be adressed later. Yours, Linus Walleij -- 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/