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

David Brownell
2007-01-01T20:16:57Z

For the list archives: here's the latest version of this.
The signed-off-by discussion is offlist right now, so this
version has none; see what eventually merges.

From: Philipp Zabel <philipp.zabel@gmail.com>

Arch-neutral GPIO calls for PXA.

Index: pxa/include/asm-arm/arch-pxa/gpio.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ pxa/include/asm-arm/arch-pxa/gpio.h 2007-01-01 11:23:43.000000000 -0800
@@ -0,0 +1,97 @@
+/*
+ * linux/include/asm-arm/arch-pxa/gpio.h
+ *
+ * PXA GPIO wrappers for arch-neutral GPIO calls
+ *
+ * Written by Philipp Zabel <philipp.zabel@gmail.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/errno.h>
+#include <asm/hardware.h>
+#include <asm/irq.h>
+
+#include <asm/arch/pxa-regs.h>
+
+static inline int gpio_get_value(unsigned gpio);
+static inline void gpio_set_value(unsigned gpio, int value);
+
+#include <asm-generic/gpio.h> /* cansleep wrappers */
+
+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)
+{
+ return pxa_gpio_mode(gpio | GPIO_IN);
+}
+
+static inline int gpio_direction_output(unsigned gpio)
+{
+ return pxa_gpio_mode(gpio | GPIO_OUT);
+}
+
+static inline int __gpio_get_value(unsigned gpio)
+{
+ return GPLR(gpio) & GPIO_bit(gpio);
+}
+
+static inline int gpio_get_value(unsigned gpio)
+{
+ if (__builtin_constant_p(gpio))
+ return __gpio_get_value(gpio);
+ else
+ 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);
+}
+
+static inline void gpio_set_value(unsigned gpio, int value)
+{
+ if (__builtin_constant_p(gpio))
+ __gpio_set_value(gpio, value);
+ else
+ pxa_gpio_set_value(gpio, value);
+}
+
+static inline int gpio_to_irq(unsigned gpio)
+{
+ if (gpio <= PXA_LAST_GPIO)
+ return IRQ_GPIO(gpio);
+ return -EINVAL;
+}
+
+#define irq_to_gpio(irq) IRQ_TO_GPIO(irq)
+
+
+#endif
Index: pxa/arch/arm/mach-pxa/generic.c
===================================================================
--- pxa.orig/arch/arm/mach-pxa/generic.c 2006-12-31 17:03:59.000000000 -0800
+++ pxa/arch/arm/mach-pxa/generic.c 2006-12-31 17:08:37.000000000 -0800
@@ -36,6 +36,7 @@
#include <asm/mach/map.h>

#include <asm/arch/pxa-regs.h>
+#include <asm/arch/gpio.h>
#include <asm/arch/udc.h>
#include <asm/arch/pxafb.h>
#include <asm/arch/mmc.h>
@@ -104,13 +105,16 @@ unsigned long long sched_clock(void)
* Handy function to set GPIO alternate functions
*/

-void pxa_gpio_mode(int gpio_mode)
+int pxa_gpio_mode(int gpio_mode)
{
unsigned long flags;
int gpio = gpio_mode & GPIO_MD_MASK_NR;
int fn = (gpio_mode & GPIO_MD_MASK_FN) >> 8;
int gafr;

+ if (gpio > PXA_LAST_GPIO)
+ return -EINVAL;
+
local_irq_save(flags);
if (gpio_mode & GPIO_DFLT_LOW)
GPCR(gpio) = GPIO_bit(gpio);
@@ -123,11 +127,33 @@ void pxa_gpio_mode(int gpio_mode)
gafr = GAFR(gpio) & ~(0x3 << (((gpio) & 0xf)*2));
GAFR(gpio) = gafr | (fn << (((gpio) & 0xf)*2));
local_irq_restore(flags);
+
+ return 0;
}

EXPORT_SYMBOL(pxa_gpio_mode);

/*
+ * Return GPIO level
+ */
+int pxa_gpio_get_value(unsigned gpio)
+{
+ return __gpio_get_value(gpio);
+}
+
+EXPORT_SYMBOL(pxa_gpio_get_value);
+
+/*
+ * Set output GPIO level
+ */
+void pxa_gpio_set_value(unsigned gpio, int value)
+{
+ __gpio_set_value(gpio, value);
+}
+
+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: pxa/include/asm-arm/arch-pxa/hardware.h
===================================================================
--- pxa.orig/include/asm-arm/arch-pxa/hardware.h 2006-12-31 17:03:59.000000000 -0800
+++ pxa/include/asm-arm/arch-pxa/hardware.h 2006-12-31 17:08:37.000000000 -0800
@@ -65,7 +65,17 @@
/*
* Handy routine to set GPIO alternate functions
*/
-extern void pxa_gpio_mode( int gpio_mode );
+extern int 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