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Diffstat (limited to 'arch/powerpc/sysdev/qe_lib/gpio.c')
-rw-r--r--arch/powerpc/sysdev/qe_lib/gpio.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/arch/powerpc/sysdev/qe_lib/gpio.c b/arch/powerpc/sysdev/qe_lib/gpio.c
new file mode 100644
index 00000000000..8e5a0bc36d0
--- /dev/null
+++ b/arch/powerpc/sysdev/qe_lib/gpio.c
@@ -0,0 +1,149 @@
+/*
+ * QUICC Engine GPIOs
+ *
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *
+ * Author: Anton Vorontsov <avorontsov@ru.mvista.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.
+ */
+
+#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 <asm/qe.h>
+
+struct qe_gpio_chip {
+ struct of_mm_gpio_chip mm_gc;
+ spinlock_t lock;
+
+ /* shadowed data register to clear/set bits safely */
+ u32 cpdata;
+};
+
+static inline struct qe_gpio_chip *
+to_qe_gpio_chip(struct of_mm_gpio_chip *mm_gc)
+{
+ return container_of(mm_gc, struct qe_gpio_chip, mm_gc);
+}
+
+static void qe_gpio_save_regs(struct of_mm_gpio_chip *mm_gc)
+{
+ struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ struct qe_pio_regs __iomem *regs = mm_gc->regs;
+
+ qe_gc->cpdata = in_be32(&regs->cpdata);
+}
+
+static int qe_gpio_get(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct qe_pio_regs __iomem *regs = mm_gc->regs;
+ u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);
+
+ return in_be32(&regs->cpdata) & pin_mask;
+}
+
+static void qe_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 qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ struct qe_pio_regs __iomem *regs = mm_gc->regs;
+ unsigned long flags;
+ u32 pin_mask = 1 << (QE_PIO_PINS - 1 - gpio);
+
+ spin_lock_irqsave(&qe_gc->lock, flags);
+
+ if (val)
+ qe_gc->cpdata |= pin_mask;
+ else
+ qe_gc->cpdata &= ~pin_mask;
+
+ out_be32(&regs->cpdata, qe_gc->cpdata);
+
+ spin_unlock_irqrestore(&qe_gc->lock, flags);
+}
+
+static int qe_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
+{
+ struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
+ struct qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&qe_gc->lock, flags);
+
+ __par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_IN, 0, 0, 0);
+
+ spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+ return 0;
+}
+
+static int qe_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 qe_gpio_chip *qe_gc = to_qe_gpio_chip(mm_gc);
+ unsigned long flags;
+
+ spin_lock_irqsave(&qe_gc->lock, flags);
+
+ __par_io_config_pin(mm_gc->regs, gpio, QE_PIO_DIR_OUT, 0, 0, 0);
+
+ spin_unlock_irqrestore(&qe_gc->lock, flags);
+
+ qe_gpio_set(gc, gpio, val);
+
+ return 0;
+}
+
+static int __init qe_add_gpiochips(void)
+{
+ struct device_node *np;
+
+ for_each_compatible_node(np, NULL, "fsl,mpc8323-qe-pario-bank") {
+ int ret;
+ struct qe_gpio_chip *qe_gc;
+ struct of_mm_gpio_chip *mm_gc;
+ struct of_gpio_chip *of_gc;
+ struct gpio_chip *gc;
+
+ qe_gc = kzalloc(sizeof(*qe_gc), GFP_KERNEL);
+ if (!qe_gc) {
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ spin_lock_init(&qe_gc->lock);
+
+ mm_gc = &qe_gc->mm_gc;
+ of_gc = &mm_gc->of_gc;
+ gc = &of_gc->gc;
+
+ mm_gc->save_regs = qe_gpio_save_regs;
+ of_gc->gpio_cells = 2;
+ gc->ngpio = QE_PIO_PINS;
+ gc->direction_input = qe_gpio_dir_in;
+ gc->direction_output = qe_gpio_dir_out;
+ gc->get = qe_gpio_get;
+ gc->set = qe_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(qe_gc);
+ /* try others anyway */
+ }
+ return 0;
+}
+arch_initcall(qe_add_gpiochips);