Re: [patch 2.6.24-rc6-mm 5/9] gpiolib: pxa platform support

From: David Brownell
Date: Sat Jan 05 2008 - 15:16:40 EST

Subject: [PATCH] gpiolib support for the PXA architecture
From: Philipp Zabel <philipp.zabel@xxxxxxxxx>

This adds gpiolib support for the PXA architecture:
- move all GPIO API functions from generic.c into gpio.c
- convert the gpio_get/set_value macros into inline functions

This makes it easier to hook up GPIOs provided by external chips like
ASICs and CPLDs.

Signed-off-by: Philipp Zabel <philipp.zabel@xxxxxxxxx>
Signed-off-by: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Acked-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxxx>
---
Incorporates minor cleanup suggested by Sam Ravnborg.

arch/arm/Kconfig | 1
arch/arm/mach-pxa/Makefile | 2
arch/arm/mach-pxa/generic.c | 93 ----------------
arch/arm/mach-pxa/generic.h | 1
arch/arm/mach-pxa/gpio.c | 197 ++++++++++++++++++++++++++++++++++++
arch/arm/mach-pxa/irq.c | 2
include/asm-arm/arch-pxa/gpio.h | 48 +++-----
include/asm-arm/arch-pxa/pxa-regs.h | 13 ++
8 files changed, 235 insertions(+), 122 deletions(-)
create mode 100644 arch/arm/mach-pxa/gpio.c

--- at91.orig/arch/arm/Kconfig 2008-01-05 12:00:47.000000000 -0800
+++ at91/arch/arm/Kconfig 2008-01-05 12:01:13.000000000 -0800
@@ -345,6 +345,7 @@ config ARCH_PXA
select GENERIC_GPIO
select GENERIC_TIME
select GENERIC_CLOCKEVENTS
+ select HAVE_GPIO_LIB
help
Support for Intel/Marvell's PXA2xx/PXA3xx processor line.

--- at91.orig/arch/arm/mach-pxa/Makefile 2008-01-05 11:46:02.000000000 -0800
+++ at91/arch/arm/mach-pxa/Makefile 2008-01-05 12:01:13.000000000 -0800
@@ -3,7 +3,7 @@
#

# Common support (must be linked before board specific support)
-obj-y += clock.o generic.o irq.o dma.o time.o
+obj-y += clock.o generic.o gpio.o irq.o dma.o time.o
obj-$(CONFIG_PXA25x) += pxa25x.o
obj-$(CONFIG_PXA27x) += pxa27x.o
obj-$(CONFIG_PXA3xx) += pxa3xx.o mfp.o
--- at91.orig/arch/arm/mach-pxa/generic.c 2008-01-05 11:46:02.000000000 -0800
+++ at91/arch/arm/mach-pxa/generic.c 2008-01-05 12:01:13.000000000 -0800
@@ -32,7 +32,6 @@
#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>
@@ -73,97 +72,6 @@ unsigned int get_memclk_frequency_10khz(
EXPORT_SYMBOL(get_memclk_frequency_10khz);

/*
- * Handy function to set GPIO alternate functions
- */
-int pxa_last_gpio;
-
-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);
- else if (gpio_mode & GPIO_DFLT_HIGH)
- GPSR(gpio) = GPIO_bit(gpio);
- if (gpio_mode & GPIO_MD_MASK_DIR)
- GPDR(gpio) |= GPIO_bit(gpio);
- else
- GPDR(gpio) &= ~GPIO_bit(gpio);
- 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);
-
-int gpio_direction_input(unsigned gpio)
-{
- unsigned long flags;
- u32 mask;
-
- if (gpio > pxa_last_gpio)
- return -EINVAL;
-
- mask = GPIO_bit(gpio);
- local_irq_save(flags);
- GPDR(gpio) &= ~mask;
- local_irq_restore(flags);
-
- return 0;
-}
-EXPORT_SYMBOL(gpio_direction_input);
-
-int gpio_direction_output(unsigned gpio, int value)
-{
- unsigned long flags;
- u32 mask;
-
- if (gpio > pxa_last_gpio)
- return -EINVAL;
-
- mask = GPIO_bit(gpio);
- local_irq_save(flags);
- if (value)
- GPSR(gpio) = mask;
- else
- GPCR(gpio) = mask;
- GPDR(gpio) |= mask;
- local_irq_restore(flags);
-
- return 0;
-}
-EXPORT_SYMBOL(gpio_direction_output);
-
-/*
- * 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)
@@ -178,7 +86,6 @@ void __pxa_set_cken(int clock, int enabl

local_irq_restore(flags);
}
-
EXPORT_SYMBOL(__pxa_set_cken);

/*
--- at91.orig/arch/arm/mach-pxa/generic.h 2008-01-05 11:46:02.000000000 -0800
+++ at91/arch/arm/mach-pxa/generic.h 2008-01-05 12:01:13.000000000 -0800
@@ -16,6 +16,7 @@ extern void __init pxa_init_irq_low(void
extern void __init pxa_init_irq_high(void);
extern void __init pxa_init_irq_gpio(int gpio_nr);
extern void __init pxa_init_irq_set_wake(int (*set_wake)(unsigned int, unsigned int));
+extern void __init pxa_init_gpio(int gpio_nr);
extern void __init pxa25x_init_irq(void);
extern void __init pxa27x_init_irq(void);
extern void __init pxa3xx_init_irq(void);
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ at91/arch/arm/mach-pxa/gpio.c 2008-01-05 12:01:13.000000000 -0800
@@ -0,0 +1,197 @@
+/*
+ * linux/arch/arm/mach-pxa/gpio.c
+ *
+ * Generic PXA GPIO handling
+ *
+ * Author: Nicolas Pitre
+ * Created: Jun 15, 2001
+ * Copyright: MontaVista Software Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+
+#include <asm/gpio.h>
+#include <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/arch/pxa-regs.h>
+
+#include "generic.h"
+
+
+struct pxa_gpio_chip {
+ struct gpio_chip chip;
+ void __iomem *regbase;
+};
+
+int pxa_last_gpio;
+
+/*
+ * Configure pins for GPIO or other functions
+ */
+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);
+ else if (gpio_mode & GPIO_DFLT_HIGH)
+ GPSR(gpio) = GPIO_bit(gpio);
+ if (gpio_mode & GPIO_MD_MASK_DIR)
+ GPDR(gpio) |= GPIO_bit(gpio);
+ else
+ GPDR(gpio) &= ~GPIO_bit(gpio);
+ 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);
+
+static int pxa_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
+{
+ unsigned long flags;
+ u32 mask = 1 << offset;
+ u32 value;
+ struct pxa_gpio_chip *pxa;
+ void __iomem *gpdr;
+
+ pxa = container_of(chip, struct pxa_gpio_chip, chip);
+ gpdr = pxa->regbase + GPDR_OFFSET;
+ local_irq_save(flags);
+ value = __raw_readl(gpdr);
+ value &= ~mask;
+ __raw_writel(value, gpdr);
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+static int pxa_gpio_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ unsigned long flags;
+ u32 mask = 1 << offset;
+ u32 tmp;
+ struct pxa_gpio_chip *pxa;
+ void __iomem *gpdr;
+
+ pxa = container_of(chip, struct pxa_gpio_chip, chip);
+ __raw_writel(mask,
+ pxa->regbase + (value ? GPSR_OFFSET : GPCR_OFFSET));
+ gpdr = pxa->regbase + GPDR_OFFSET;
+ local_irq_save(flags);
+ tmp = __raw_readl(gpdr);
+ tmp |= mask;
+ __raw_writel(tmp, gpdr);
+ local_irq_restore(flags);
+
+ return 0;
+}
+
+/*
+ * Return GPIO level
+ */
+static int pxa_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ u32 mask = 1 << offset;
+ struct pxa_gpio_chip *pxa;
+
+ pxa = container_of(chip, struct pxa_gpio_chip, chip);
+ return __raw_readl(pxa->regbase + GPLR_OFFSET) & mask;
+}
+
+/*
+ * Set output GPIO level
+ */
+static void pxa_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ u32 mask = 1 << offset;
+ struct pxa_gpio_chip *pxa;
+
+ pxa = container_of(chip, struct pxa_gpio_chip, chip);
+
+ if (value)
+ __raw_writel(mask, pxa->regbase + GPSR_OFFSET);
+ else
+ __raw_writel(mask, pxa->regbase + GPCR_OFFSET);
+}
+
+static struct pxa_gpio_chip pxa_gpio_chip[] = {
+ [0] = {
+ .regbase = GPIO0_BASE,
+ .chip = {
+ .label = "gpio-0",
+ .direction_input = pxa_gpio_direction_input,
+ .direction_output = pxa_gpio_direction_output,
+ .get = pxa_gpio_get,
+ .set = pxa_gpio_set,
+ .base = 0,
+ .ngpio = 32,
+ },
+ },
+ [1] = {
+ .regbase = GPIO1_BASE,
+ .chip = {
+ .label = "gpio-1",
+ .direction_input = pxa_gpio_direction_input,
+ .direction_output = pxa_gpio_direction_output,
+ .get = pxa_gpio_get,
+ .set = pxa_gpio_set,
+ .base = 32,
+ .ngpio = 32,
+ },
+ },
+ [2] = {
+ .regbase = GPIO2_BASE,
+ .chip = {
+ .label = "gpio-2",
+ .direction_input = pxa_gpio_direction_input,
+ .direction_output = pxa_gpio_direction_output,
+ .get = pxa_gpio_get,
+ .set = pxa_gpio_set,
+ .base = 64,
+ .ngpio = 32, /* 21 for PXA25x */
+ },
+ },
+#if defined(CONFIG_PXA27x) || defined(CONFIG_PXA3xx)
+ [3] = {
+ .regbase = GPIO3_BASE,
+ .chip = {
+ .label = "gpio-3",
+ .direction_input = pxa_gpio_direction_input,
+ .direction_output = pxa_gpio_direction_output,
+ .get = pxa_gpio_get,
+ .set = pxa_gpio_set,
+ .base = 96,
+ .ngpio = 32,
+ },
+ },
+#endif
+};
+
+void __init pxa_init_gpio(int gpio_nr)
+{
+ int i;
+
+ /* add a GPIO chip for each register bank.
+ * the last PXA25x register only contains 21 GPIOs
+ */
+ for (i = 0; i < gpio_nr; i += 32) {
+ if (i+32 > gpio_nr)
+ pxa_gpio_chip[i/32].chip.ngpio = gpio_nr - i;
+ gpiochip_add(&pxa_gpio_chip[i/32].chip);
+ }
+}
--- at91.orig/arch/arm/mach-pxa/irq.c 2008-01-05 11:46:02.000000000 -0800
+++ at91/arch/arm/mach-pxa/irq.c 2008-01-05 12:01:13.000000000 -0800
@@ -310,6 +310,8 @@ void __init pxa_init_irq_gpio(int gpio_n
/* Install handler for GPIO>=2 edge detect interrupts */
set_irq_chip(IRQ_GPIO_2_x, &pxa_internal_chip_low);
set_irq_chained_handler(IRQ_GPIO_2_x, pxa_gpio_demux_handler);
+
+ pxa_init_gpio(gpio_nr);
}

void __init pxa_init_irq_set_wake(int (*set_wake)(unsigned int, unsigned int))
--- at91.orig/include/asm-arm/arch-pxa/gpio.h 2008-01-05 11:46:02.000000000 -0800
+++ at91/include/asm-arm/arch-pxa/gpio.h 2008-01-05 12:01:13.000000000 -0800
@@ -28,43 +28,35 @@
#include <asm/irq.h>
#include <asm/hardware.h>

-static inline int gpio_request(unsigned gpio, const char *label)
-{
- return 0;
-}
+#include <asm-generic/gpio.h>

-static inline void gpio_free(unsigned gpio)
-{
- return;
-}

-extern int gpio_direction_input(unsigned gpio);
-extern int gpio_direction_output(unsigned gpio, int value);
+/* NOTE: some PXAs have fewer on-chip GPIOs (like PXA255, with 85).
+ * Those cases currently cause holes in the GPIO number space.
+ */
+#define NR_BUILTIN_GPIO 128

-static inline int __gpio_get_value(unsigned gpio)
+static inline int gpio_get_value(unsigned gpio)
{
- return GPLR(gpio) & GPIO_bit(gpio);
+ if (__builtin_constant_p(gpio) && (gpio < NR_BUILTIN_GPIO))
+ return GPLR(gpio) & GPIO_bit(gpio);
+ else
+ return __gpio_get_value(gpio);
}

-#define gpio_get_value(gpio) \
- (__builtin_constant_p(gpio) ? \
- __gpio_get_value(gpio) : \
- pxa_gpio_get_value(gpio))
-
-static inline void __gpio_set_value(unsigned gpio, int value)
+static inline void gpio_set_value(unsigned gpio, int value)
{
- if (value)
- GPSR(gpio) = GPIO_bit(gpio);
- else
- GPCR(gpio) = GPIO_bit(gpio);
+ if (__builtin_constant_p(gpio) && (gpio < NR_BUILTIN_GPIO)) {
+ if (value)
+ GPSR(gpio) = GPIO_bit(gpio);
+ else
+ GPCR(gpio) = GPIO_bit(gpio);
+ } else {
+ __gpio_set_value(gpio, value);
+ }
}

-#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_cansleep __gpio_cansleep

#define gpio_to_irq(gpio) IRQ_GPIO(gpio)
#define irq_to_gpio(irq) IRQ_TO_GPIO(irq)
--- at91.orig/include/asm-arm/arch-pxa/pxa-regs.h 2008-01-05 11:46:02.000000000 -0800
+++ at91/include/asm-arm/arch-pxa/pxa-regs.h 2008-01-05 12:01:13.000000000 -0800
@@ -1131,6 +1131,19 @@
* General Purpose I/O
*/

+#define GPIO0_BASE ((void __iomem *)io_p2v(0x40E00000))
+#define GPIO1_BASE ((void __iomem *)io_p2v(0x40E00004))
+#define GPIO2_BASE ((void __iomem *)io_p2v(0x40E00008))
+#define GPIO3_BASE ((void __iomem *)io_p2v(0x40E00100))
+
+#define GPLR_OFFSET 0x00
+#define GPDR_OFFSET 0x0C
+#define GPSR_OFFSET 0x18
+#define GPCR_OFFSET 0x24
+#define GRER_OFFSET 0x30
+#define GFER_OFFSET 0x3C
+#define GEDR_OFFSET 0x48
+
#define GPLR0 __REG(0x40E00000) /* GPIO Pin-Level Register GPIO<31:0> */
#define GPLR1 __REG(0x40E00004) /* GPIO Pin-Level Register GPIO<63:32> */
#define GPLR2 __REG(0x40E00008) /* GPIO Pin-Level Register GPIO<80:64> */
--
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