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powerpc/QE: implement support for the GPIO LIB API

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This is needed to access QE GPIOs via Linux GPIO API.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-By: Timur Tabi <timur@freescale.com>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
This commit is contained in:
Anton Vorontsov
2008-05-19 21:47:05 +04:00
committed by Kumar Gala
parent 9572653ee0
commit 32def337aa
5 changed files with 186 additions and 0 deletions
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146
arch/powerpc/sysdev/qe_lib/gpio.c Normal file
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/*
* 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/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;
}
void __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 */
}
}