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

From: pHilipp Zabel
Date: Thu Dec 21 2006 - 10:05:50 EST


On 12/21/06, Nicolas Pitre <nico@xxxxxxx> 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@xxxxxxxxx>
+ *
+ * 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);
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@xxxxxxxxx>
+ *
+ * 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);