This patch adds a gpio driver for MPC512X PowerPCs.
It has been tested on our CAN-CBX-CPU5201 module that
uses a MPC5121 CPU. This platform comes with a couple of
LEDs and configuration switches that have been used for testing.
Signed-off-by: Matthias Fuchs <matthias.fu...@esd.eu>
---
v2: - move driver to arch/powerpc/platforms/512x directory
- Kconfig changes are now in arch/powerpc/platform/512x/Kconfig
- put struct mpc512x_gpio_regs in driver's .c file
- rename GPIO_MASK into MPC512x_GPIO_MASK
- use shadow registers instead of r/m/w-operations
- don't use arch_initcall but call mpc512x_add_gpiochips()
from mpc512x platform setup code.
arch/powerpc/platforms/512x/Kconfig | 9 ++
arch/powerpc/platforms/512x/Makefile | 1 +
arch/powerpc/platforms/512x/mpc512x.h | 3 +
arch/powerpc/platforms/512x/mpc512x_gpio.c | 198 ++++++++++++++++++++++++++
arch/powerpc/platforms/512x/mpc512x_shared.c | 3 +
5 files changed, 214 insertions(+), 0 deletions(-)
create mode 100644 arch/powerpc/platforms/512x/mpc512x_gpio.c
diff --git a/arch/powerpc/platforms/512x/Kconfig
b/arch/powerpc/platforms/512x/Kconfig
index 4dac9b0..840c6b4 100644
--- a/arch/powerpc/platforms/512x/Kconfig
+++ b/arch/powerpc/platforms/512x/Kconfig
@@ -10,6 +10,15 @@ config PPC_MPC5121
bool
select PPC_MPC512x
+config MPC512x_GPIO
+ bool "MPC512x GPIO support"
+ depends on PPC_MPC512x
+ select GENERIC_GPIO
+ select ARCH_REQUIRE_GPIOLIB
+ help
+ Say Y here if you're going to use hardware that connects to the
+ MPC512x GPIOs.
+
config MPC5121_ADS
bool "Freescale MPC5121E ADS"
depends on 6xx
diff --git a/arch/powerpc/platforms/512x/Makefile
b/arch/powerpc/platforms/512x/Makefile
index 90be2f5..12518e3 100644
--- a/arch/powerpc/platforms/512x/Makefile
+++ b/arch/powerpc/platforms/512x/Makefile
@@ -4,3 +4,4 @@
obj-y += clock.o mpc512x_shared.o
obj-$(CONFIG_MPC5121_ADS) += mpc5121_ads.o mpc5121_ads_cpld.o
obj-$(CONFIG_MPC5121_GENERIC) += mpc5121_generic.o
+obj-$(CONFIG_MPC512x_GPIO) += mpc512x_gpio.o
diff --git a/arch/powerpc/platforms/512x/mpc512x.h
b/arch/powerpc/platforms/512x/mpc512x.h
index b2daca0..4c67990 100644
--- a/arch/powerpc/platforms/512x/mpc512x.h
+++ b/arch/powerpc/platforms/512x/mpc512x.h
@@ -16,4 +16,7 @@ extern void __init mpc512x_init(void);
extern int __init mpc5121_clk_init(void);
void __init mpc512x_declare_of_platform_devices(void);
extern void mpc512x_restart(char *cmd);
+#ifdef CONFIG_MPC512x_GPIO
+extern int __init mpc512x_add_gpiochips(void);
+#endif
#endif /* __MPC512X_H__ */
diff --git a/arch/powerpc/platforms/512x/mpc512x_gpio.c
b/arch/powerpc/platforms/512x/mpc512x_gpio.c
new file mode 100644
index 0000000..fc6ad82
--- /dev/null
+++ b/arch/powerpc/platforms/512x/mpc512x_gpio.c
@@ -0,0 +1,198 @@
+/*
+ * MPC512x gpio driver
+ *
+ * Copyright (c) 2010 Matthias Fuchs <matthias.fu...@esd.eu>, esd gmbh
+ *
+ * derived from ppc4xx gpio driver
+ *
+ * Copyright (c) 2008 Harris Corporation
+ * Copyright (c) 2008 Sascha Hauer <s.ha...@pengutronix.de>, Pengutronix
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *
+ * Author: Steve Falco <sfa...@harris.com>
+ *
+ * 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.
+ *
+ * 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
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_gpio.h>
+#include <linux/gpio.h>
+#include <linux/types.h>
+
+#define MPC512x_GPIO_MASK(gpio) (0x80000000 >> (gpio))
+
+struct mpc512x_gpio_regs {
+ u32 gpdir;
+ u32 gpodr;
+ u32 gpdat;
+ u32 gpier;
+ u32 gpimr;
+ u32 gpicr1;
+ u32 gpicr2;
+};
+
+struct mpc512x_chip {
+ struct of_mm_gpio_chip mm_gc;
+ spinlock_t lock;
+
+ /* shadow registers */
+ u32 dat;
+ u32 odr;
+ u32 dir;
+};
+
+/*
+ * GPIO LIB API implementation for GPIOs
+ *
+ * There are a maximum of 32 gpios in each gpio controller.
+ */
+static inline struct mpc512x_chip *
+to_mpc512x_gpiochip(struct of_mm_gpio_chip *mm_gc)
+{
+ return container_of(mm_gc, struct mpc512x_chip, mm_gc);
+}
+
+static int mpc512x_gpio_get(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct mpc512x_gpio_regs __iomem *regs = mm_gc->regs;
+
+ return in_be32(®s->gpdat) & MPC512x_GPIO_MASK(gpio);
+}
+
+static inline void
+__mpc512x_gpio_set(struct of_mm_gpio_chip *mm_gc, unsigned int gpio, int val)
+{
+ struct mpc512x_chip *chip = to_mpc512x_gpiochip(mm_gc);
+ struct mpc512x_gpio_regs __iomem *regs = mm_gc->regs;
+
+
+ if (val)
+ chip->dat |= MPC512x_GPIO_MASK(gpio);
+ else
+ chip->dat &= ~MPC512x_GPIO_MASK(gpio);
+
+ out_be32(®s->gpdat, chip->dat);
+}
+
+static void
+mpc512x_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct mpc512x_chip *chip = to_mpc512x_gpiochip(mm_gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ __mpc512x_gpio_set(mm_gc, gpio, val);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
+}
+
+static int mpc512x_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct mpc512x_chip *chip = to_mpc512x_gpiochip(mm_gc);
+ struct mpc512x_gpio_regs __iomem *regs = mm_gc->regs;
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ /* Disable open-drain function */
+ chip->odr &= ~MPC512x_GPIO_MASK(gpio);
+ out_be32(®s->gpodr, chip->odr);
+
+ /* Float the pin */
+ chip->dir &= ~MPC512x_GPIO_MASK(gpio);
+ out_be32(®s->gpdir, chip->dir);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ return 0;
+}
+
+static int
+mpc512x_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct mpc512x_chip *chip = to_mpc512x_gpiochip(mm_gc);
+ struct mpc512x_gpio_regs __iomem *regs = mm_gc->regs;
+ unsigned long flags;
+
+ spin_lock_irqsave(&chip->lock, flags);
+
+ /* First set initial value */
+ __mpc512x_gpio_set(mm_gc, gpio, val);
+
+ /* Disable open-drain function */
+ chip->odr &= ~MPC512x_GPIO_MASK(gpio);
+ out_be32(®s->gpodr, chip->odr);
+
+ /* Drive the pin */
+ chip->dir |= MPC512x_GPIO_MASK(gpio);
+ out_be32(®s->gpdir, chip->dir);
+
+ spin_unlock_irqrestore(&chip->lock, flags);
+
+ pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
+
+ return 0;
+}
+
+void __init mpc512x_add_gpiochips(void)
+{
+ struct device_node *np;
+
+ for_each_compatible_node(np, NULL, "fsl,mpc5121-gpio") {
+ int ret;
+ struct mpc512x_chip *chip;
+ struct of_mm_gpio_chip *mm_gc;
+ struct of_gpio_chip *of_gc;
+ struct gpio_chip *gc;
+
+ chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+ if (!chip) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ spin_lock_init(&chip->lock);
+
+ mm_gc = &chip->mm_gc;
+ of_gc = &mm_gc->of_gc;
+ gc = &of_gc->gc;
+
+ gc->ngpio = 32;
+ gc->direction_input = mpc512x_gpio_dir_in;
+ gc->direction_output = mpc512x_gpio_dir_out;
+ gc->get = mpc512x_gpio_get;
+ gc->set = mpc512x_gpio_set;
+
+ ret = of_mm_gpiochip_add(np, mm_gc);
+ if (ret)
+ goto err;
+ continue;
+err:
+ pr_err("%s: registration failed with status %d\n",
+ np->full_name, ret);
+ kfree(chip);
+ /* try others anyway */
+ }
+}
diff --git a/arch/powerpc/platforms/512x/mpc512x_shared.c
b/arch/powerpc/platforms/512x/mpc512x_shared.c
index b7f518a..42320ab 100644
--- a/arch/powerpc/platforms/512x/mpc512x_shared.c
+++ b/arch/powerpc/platforms/512x/mpc512x_shared.c
@@ -100,4 +100,7 @@ void __init mpc512x_init(void)
mpc512x_declare_of_platform_devices();
mpc5121_clk_init();
mpc512x_restart_init();
+#ifdef CONFIG_MPC512x_GPIO
+ mpc512x_add_gpiochips();
+#endif
}
--
1.6.1
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