linux-kernel - Re: [patch 2.6.20-rc1 4/6] PXA GPIO wrappers

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives
Hash Suite for Android: free password hash cracker in your pocket
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Thu, 21 Dec 2006 16:03:42 +0100
From:	"pHilipp Zabel" <philipp.zabel@...il.com>
To:	"Nicolas Pitre" <nico@....org>
Cc:	"David Brownell" <david-b@...bell.net>,
	"Andrew Morton" <akpm@...l.org>,
	"Linux Kernel list" <linux-kernel@...r.kernel.org>,
	"Andrew Victor" <andrew@...people.com>,
	"Bill Gatliff" <bgat@...lgatliff.com>,
	"Haavard Skinnemoen" <hskinnemoen@...el.com>, jamey.hicks@...com,
	"Kevin Hilman" <khilman@...sta.com>,
	"Russell King" <rmk@....linux.org.uk>,
	"Tony Lindgren" <tony@...mide.com>
Subject: Re: [patch 2.6.20-rc1 4/6] PXA GPIO wrappers

On 12/21/06, Nicolas Pitre <nico@....org> wrote:
> On Wed, 20 Dec 2006, David Brownell wrote:
>
> > On Wednesday 20 December 2006 10:12 pm, Andrew Morton wrote:
> > > Why not implement them as inline functions?
> >
> > I just collected and forwarded the code from Philip...
> > the better not to lose such stuff!  :)
> >
> >
> > > Or non-inline functions, come to that.
> >
> > In this case I think that'd be preferable; see what those macros
> > expand to on pxa27x CPUs.
>
> Only if the gpio argument is not constant please.  When it is constant
> this expands to a single word store.
>
>
> Nicolas

David suggested to have both inline and non-inline functions depending
on whether gpio is constant. How is this patch?

regards
Philipp

Index: linux-2.6/include/asm-arm/arch-pxa/gpio.h
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6/include/asm-arm/arch-pxa/gpio.h	2006-12-21
07:57:12.000000000 +0100
@@ -0,0 +1,86 @@
+/*
+ * linux/include/asm-arm/arch-pxa/gpio.h
+ *
+ * PXA GPIO wrappers for arch-neutral GPIO calls
+ *
+ * Written by Philipp Zabel <philipp.zabel@...il.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+#ifndef __ASM_ARCH_PXA_GPIO_H
+#define __ASM_ARCH_PXA_GPIO_H
+
+#include <asm/arch/pxa-regs.h>
+#include <asm/arch/irqs.h>
+#include <asm/arch/hardware.h>
+
+#include <asm/errno.h>
+
+static inline int gpio_request(unsigned gpio, const char *label)
+{
+	return 0;
+}
+
+static inline void gpio_free(unsigned gpio)
+{
+	return;
+}
+
+static inline int gpio_direction_input(unsigned gpio)
+{
+	if (gpio > PXA_LAST_GPIO)
+		return -EINVAL;
+	pxa_gpio_mode(gpio | GPIO_IN);
+}
+
+static inline int gpio_direction_output(unsigned gpio)
+{
+	if (gpio > PXA_LAST_GPIO)
+		return -EINVAL;
+	pxa_gpio_mode(gpio | GPIO_OUT);
+}
+
+static inline int __gpio_get_value(unsigned gpio)
+{
+	return GPLR(gpio) & GPIO_bit(gpio);
+}
+
+#define gpio_get_value(gpio)			\
+	(__builtin_constant_p(gpio) ?		\
+	 __gpioe_get_value(gpio) :		\
+	 pxa_gpio_get_value(gpio))
+
+static inline void __gpio_set_value(unsigned gpio, int value)
+{
+	if (value)
+		GPSR(gpio) = GPIO_bit(gpio);
+	else
+		GPCR(gpio) = GPIO_bit(gpio);
+}
+
+#define gpio_set_value(gpio,value)		\
+	(__builtin_constant_p(gpio) ?		\
+	 __gpio_set_value(gpio, value) :	\
+	 pxa_gpio_set_value(gpio, value))
+
+#include <asm-generic/gpio.h>			/* cansleep wrappers */
+
+#define gpio_to_irq(gpio)	IRQ_GPIO(gpio)
+#define irq_to_gpio(irq)	IRQ_TO_GPIO(irq)
+
+
+#endif
Index: linux-2.6/arch/arm/mach-pxa/generic.c
===================================================================
--- linux-2.6.orig/arch/arm/mach-pxa/generic.c	2006-12-16
16:47:42.000000000 +0100
+++ linux-2.6/arch/arm/mach-pxa/generic.c	2006-12-16 16:47:45.000000000 +0100
@@ -129,6 +129,29 @@
 EXPORT_SYMBOL(pxa_gpio_mode);

 /*
+ * Return GPIO level, nonzero means high, zero is low
+ */
+int pxa_gpio_get_value(unsigned gpio)
+{
+	return GPLR(gpio) & GPIO_bit(gpio);
+}
+
+EXPORT_SYMBOL(pxa_gpio_get_value);
+
+/*
+ * Set output GPIO level
+ */
+void pxa_gpio_set_value(unsigned gpio, int value)
+{
+	if (value)
+		GPSR(gpio) = GPIO_bit(gpio);
+	else
+		GPCR(gpio) = GPIO_bit(gpio);
+}
+
+EXPORT_SYMBOL(pxa_gpio_set_value);
+
+/*
  * Routine to safely enable or disable a clock in the CKEN
  */
 void pxa_set_cken(int clock, int enable)
Index: linux-2.6/include/asm-arm/arch-pxa/hardware.h
===================================================================
--- linux-2.6.orig/include/asm-arm/arch-pxa/hardware.h	2006-12-17
15:42:36.000000000 +0100
+++ linux-2.6/include/asm-arm/arch-pxa/hardware.h	2006-12-17
15:43:26.000000000 +0100
@@ -68,6 +68,16 @@
 extern void pxa_gpio_mode( int gpio_mode );

 /*
+ * Return GPIO level, nonzero means high, zero is low
+ */
+extern int pxa_gpio_get_value(unsigned gpio);
+
+/*
+ * Set output GPIO level
+ */
+extern void pxa_gpio_set_value(unsigned gpio, int value);
+
+/*
  * Routine to enable or disable CKEN
  */
 extern void pxa_set_cken(int clock, int enable);

View attachment "gpio-api-pxa.patch" of type "text/x-patch" (3985 bytes)