From: Kukjin Kim <kgene.kim@samsung.com> To: "'Lars-Peter Clausen'" <lars@metafoo.de> Cc: "'Ben Dooks'" <ben-linux@fluff.org>, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: RE: [PATCH 08/09] ARM: s3c2440: gta02: Request usb pullup pin before using it Date: Mon, 28 Feb 2011 19:44:25 +0900 [thread overview] Message-ID: <003201cbd734$79d87050$6d8950f0$%kim@samsung.com> (raw) In-Reply-To: <4D6B7826.1030500@metafoo.de> 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 <lars@metafoo.de> > >> --- > >> 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 <kgene.kim@samsung.com>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.
WARNING: multiple messages have this Message-ID (diff)
From: kgene.kim@samsung.com (Kukjin Kim) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 08/09] ARM: s3c2440: gta02: Request usb pullup pin before using it Date: Mon, 28 Feb 2011 19:44:25 +0900 [thread overview] Message-ID: <003201cbd734$79d87050$6d8950f0$%kim@samsung.com> (raw) In-Reply-To: <4D6B7826.1030500@metafoo.de> 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 <lars@metafoo.de> > >> --- > >> 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 <kgene.kim@samsung.com>, Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd.
next prev parent reply other threads:[~2011-02-28 10:44 UTC|newest] Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top 2011-02-07 1:51 [PATCH 01/09] ARM: s3c2442: gta02: Fix usage gpio bank j pin definitions Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-07 1:51 ` [PATCH 02/09] ARM: s3c2440: gta02: Register PCM device Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-28 6:38 ` Kukjin Kim 2011-02-28 6:38 ` Kukjin Kim 2011-02-07 1:51 ` [PATCH 03/09] ARM: s3c2440: gta02: Add button support Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-28 6:37 ` Kukjin Kim 2011-02-28 6:37 ` Kukjin Kim 2011-02-07 1:51 ` [PATCH 04/09] ARM: s3c2440: gta02: Select missing S3C_DEV_USB_HOST Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-28 6:31 ` Kukjin Kim 2011-02-28 6:31 ` Kukjin Kim 2011-02-07 1:51 ` [PATCH 05/09] ARM: s3c2440: gta02: Fix regulator valid_modes_ops Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-28 6:48 ` Kukjin Kim 2011-02-28 6:48 ` Kukjin Kim 2011-02-07 1:51 ` [PATCH 06/09] ARM: s3c2440: gta02: Remove state_mem constraints for the pcf50633 regulators Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-28 6:26 ` Kukjin Kim 2011-02-28 6:26 ` Kukjin Kim 2011-02-28 10:28 ` Lars-Peter Clausen 2011-02-28 10:28 ` Lars-Peter Clausen 2011-02-28 10:58 ` Kukjin Kim 2011-02-28 10:58 ` Kukjin Kim 2011-02-07 1:51 ` [PATCH 07/09] ARM: s3c2440: gta02: Call regulator_has_full_constraints Lars-Peter Clausen 2011-02-07 1:51 ` Lars-Peter Clausen 2011-02-07 11:58 ` Mark Brown 2011-02-07 11:58 ` Mark Brown 2011-02-08 2:55 ` [PATCH v2 " Lars-Peter Clausen 2011-02-08 2:55 ` Lars-Peter Clausen 2011-02-28 6:47 ` Kukjin Kim 2011-02-28 6:47 ` Kukjin Kim 2011-02-07 1:52 ` [PATCH 08/09] ARM: s3c2440: gta02: Request usb pullup pin before using it Lars-Peter Clausen 2011-02-07 1:52 ` Lars-Peter Clausen 2011-02-28 6:16 ` Kukjin Kim 2011-02-28 6:16 ` Kukjin Kim 2011-02-28 10:25 ` Lars-Peter Clausen 2011-02-28 10:25 ` Lars-Peter Clausen 2011-02-28 10:44 ` Kukjin Kim [this message] 2011-02-28 10:44 ` Kukjin Kim 2011-02-28 10:58 ` Lars-Peter Clausen 2011-02-28 10:58 ` Lars-Peter Clausen 2011-03-07 6:42 ` Kukjin Kim 2011-03-07 6:42 ` Kukjin Kim 2011-03-07 7:00 ` Lars-Peter Clausen 2011-03-07 7:00 ` Lars-Peter Clausen 2011-02-07 1:52 ` [PATCH 09/09] ARM: s3c2440: gta02: Add touchscreen support Lars-Peter Clausen 2011-02-07 1:52 ` Lars-Peter Clausen 2011-02-28 6:04 ` Kukjin Kim 2011-02-28 6:04 ` Kukjin Kim 2011-02-28 10:44 ` Lars-Peter Clausen 2011-02-28 10:44 ` Lars-Peter Clausen 2011-02-28 10:57 ` Kukjin Kim 2011-02-28 10:57 ` Kukjin Kim 2011-02-28 11:17 ` [PATCH v2 " Lars-Peter Clausen 2011-02-28 11:17 ` Lars-Peter Clausen 2011-02-28 11:56 ` Kukjin Kim 2011-02-28 11:56 ` Kukjin Kim 2011-02-18 10:41 ` [PATCH 01/09] ARM: s3c2442: gta02: Fix usage gpio bank j pin definitions Lars-Peter Clausen 2011-02-18 10:41 ` Lars-Peter Clausen 2011-02-21 9:58 ` Kukjin Kim 2011-02-21 9:58 ` Kukjin Kim 2011-02-28 6:41 ` Kukjin Kim 2011-02-28 6:41 ` Kukjin Kim 2011-02-28 10:46 ` Lars-Peter Clausen 2011-02-28 10:46 ` Lars-Peter Clausen 2011-02-28 10:49 ` Kukjin Kim 2011-02-28 10:49 ` Kukjin Kim
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to='003201cbd734$79d87050$6d8950f0$%kim@samsung.com' \ --to=kgene.kim@samsung.com \ --cc=ben-linux@fluff.org \ --cc=lars@metafoo.de \ --cc=linux-arm-kernel@lists.infradead.org \ --cc=linux-kernel@vger.kernel.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes, see mirroring instructions on how to clone and mirror all data and code used by this external index.