From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753491Ab1B1Kob (ORCPT ); Mon, 28 Feb 2011 05:44:31 -0500 Received: from mailout3.samsung.com ([203.254.224.33]:43746 "EHLO mailout3.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752886Ab1B1Koa (ORCPT ); Mon, 28 Feb 2011 05:44:30 -0500 Date: Mon, 28 Feb 2011 19:44:25 +0900 From: Kukjin Kim Subject: RE: [PATCH 08/09] ARM: s3c2440: gta02: Request usb pullup pin before using it In-reply-to: <4D6B7826.1030500@metafoo.de> To: "'Lars-Peter Clausen'" Cc: "'Ben Dooks'" , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Message-id: <003201cbd734$79d87050$6d8950f0$%kim@samsung.com> MIME-version: 1.0 X-Mailer: Microsoft Office Outlook 12.0 Content-type: text/plain; charset=us-ascii Content-language: ko Content-transfer-encoding: 7BIT Thread-index: AcvXMobLmP58a6k6SqmvcZc3hMOBxAAAQdVQ References: <1297043521-21903-1-git-send-email-lars@metafoo.de> <1297043521-21903-8-git-send-email-lars@metafoo.de> <000301cbd70f$12367070$36a35150$%kim@samsung.com> <4D6B7826.1030500@metafoo.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Lars-Peter Clausen wrote: > > On 02/28/2011 07:16 AM, Kukjin Kim wrote: > > Lars-Peter Clausen wrote: > >> > >> Request the gpio pin used to control the usb pullup before using it to > > avoid > >> a > >> runtime warning about an auto-requested gpio. > >> > >> Signed-off-by: Lars-Peter Clausen > >> --- > >> arch/arm/mach-s3c2440/mach-gta02.c | 17 +++++++++++++++-- > >> 1 files changed, 15 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/arm/mach-s3c2440/mach-gta02.c > > b/arch/arm/mach-s3c2440/mach- > >> gta02.c > >> index 1396639..94456fa 100644 > >> --- a/arch/arm/mach-s3c2440/mach-gta02.c > >> +++ b/arch/arm/mach-s3c2440/mach-gta02.c > >> @@ -451,11 +451,11 @@ static void gta02_udc_command(enum s3c2410_udc_cmd_e > >> cmd) > >> switch (cmd) { > >> case S3C2410_UDC_P_ENABLE: > >> pr_debug("%s S3C2410_UDC_P_ENABLE\n", __func__); > >> - gpio_direction_output(GTA02_GPIO_USB_PULLUP, 1); > >> + gpio_set_value(GTA02_GPIO_USB_PULLUP, 1); > > > > How about following instead? > > gpio_request(GTA02_GPIO_USB_PULLUP, "USB_PULLUP"); > > gpio_direction_output(GTA02_GPIO_USB_PULLUP, 1); > > gpio_free(GTA02_GPIO_USB_PULLUP); > > > > I don't think that is a good idea. This gpio should really be reserved for > the > udc driver. If it is freed again, it could be requested from someone else > which > could lead to undefined behaviour. > Yes right, but I mean the board designer already knows the usage of regarding GPIOs on his board. So why do we really need gpio_request for it?... Thanks. Best regards, Kgene. -- Kukjin Kim , Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd. From mboxrd@z Thu Jan 1 00:00:00 1970 From: kgene.kim@samsung.com (Kukjin Kim) Date: Mon, 28 Feb 2011 19:44:25 +0900 Subject: [PATCH 08/09] ARM: s3c2440: gta02: Request usb pullup pin before using it In-Reply-To: <4D6B7826.1030500@metafoo.de> References: <1297043521-21903-1-git-send-email-lars@metafoo.de> <1297043521-21903-8-git-send-email-lars@metafoo.de> <000301cbd70f$12367070$36a35150$%kim@samsung.com> <4D6B7826.1030500@metafoo.de> Message-ID: <003201cbd734$79d87050$6d8950f0$%kim@samsung.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Lars-Peter Clausen wrote: > > On 02/28/2011 07:16 AM, Kukjin Kim wrote: > > Lars-Peter Clausen wrote: > >> > >> Request the gpio pin used to control the usb pullup before using it to > > avoid > >> a > >> runtime warning about an auto-requested gpio. > >> > >> Signed-off-by: Lars-Peter Clausen > >> --- > >> arch/arm/mach-s3c2440/mach-gta02.c | 17 +++++++++++++++-- > >> 1 files changed, 15 insertions(+), 2 deletions(-) > >> > >> diff --git a/arch/arm/mach-s3c2440/mach-gta02.c > > b/arch/arm/mach-s3c2440/mach- > >> gta02.c > >> index 1396639..94456fa 100644 > >> --- a/arch/arm/mach-s3c2440/mach-gta02.c > >> +++ b/arch/arm/mach-s3c2440/mach-gta02.c > >> @@ -451,11 +451,11 @@ static void gta02_udc_command(enum s3c2410_udc_cmd_e > >> cmd) > >> switch (cmd) { > >> case S3C2410_UDC_P_ENABLE: > >> pr_debug("%s S3C2410_UDC_P_ENABLE\n", __func__); > >> - gpio_direction_output(GTA02_GPIO_USB_PULLUP, 1); > >> + gpio_set_value(GTA02_GPIO_USB_PULLUP, 1); > > > > How about following instead? > > gpio_request(GTA02_GPIO_USB_PULLUP, "USB_PULLUP"); > > gpio_direction_output(GTA02_GPIO_USB_PULLUP, 1); > > gpio_free(GTA02_GPIO_USB_PULLUP); > > > > I don't think that is a good idea. This gpio should really be reserved for > the > udc driver. If it is freed again, it could be requested from someone else > which > could lead to undefined behaviour. > Yes right, but I mean the board designer already knows the usage of regarding GPIOs on his board. So why do we really need gpio_request for it?... Thanks. Best regards, Kgene. -- Kukjin Kim , Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.