/*
* Driver for Aeroflex Gaisler GRGPIO General Purpose I/O cores.
*
* 2013 (c) Aeroflex Gaisler AB
*
* This driver supports the GRGPIO GPIO core available in the GRLIB VHDL
* IP core library.
*
* Full documentation of the GRGPIO core can be found here:
* http://www.gaisler.com/products/grlib/grip.pdf
*
* See "Documentation/devicetree/bindings/gpio/gpio-grgpio.txt" for
* information on open firmware properties.
*
* 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.
*
* Contributors: Andreas Larsson <andreas@gaisler.com>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_platform.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/basic_mmio_gpio.h>
#define GRGPIO_MAX_NGPIO 32
#define GRGPIO_DATA 0x00
#define GRGPIO_OUTPUT 0x04
#define GRGPIO_DIR 0x08
#define GRGPIO_IMASK 0x0c
#define GRGPIO_IPOL 0x10
#define GRGPIO_IEDGE 0x14
#define GRGPIO_BYPASS 0x18
#define GRGPIO_IMAP_BASE 0x20
struct grgpio_priv {
struct bgpio_chip bgc;
void __iomem *regs;
struct device *dev;
};
static inline struct grgpio_priv *grgpio_gc_to_priv(struct gpio_chip *gc)
{
struct bgpio_chip *bgc = to_bgpio_chip(gc);
return container_of(bgc, struct grgpio_priv, bgc);
}
static int grgpio_probe(struct platform_device *ofdev)
{
struct device_node *np = ofdev->dev.of_node;
void __iomem *regs;
struct gpio_chip *gc;
struct bgpio_chip *bgc;
struct grgpio_priv *priv;
struct resource *res;
int err;
u32 prop;
priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
regs = devm_ioremap_resource(&ofdev->dev, res);
if (IS_ERR(regs))
return PTR_ERR(regs);
bgc = &priv->bgc;
err = bgpio_init(bgc, &ofdev->dev, 4, regs + GRGPIO_DATA,
regs + GRGPIO_OUTPUT, NULL, regs + GRGPIO_DIR, NULL,
BGPIOF_BIG_ENDIAN_BYTE_ORDER);
if (err) {
dev_err(&ofdev->dev, "bgpio_init() failed\n");
return err;
}
priv->regs = regs;
priv->dev = &ofdev->dev;
gc = &bgc->gc;
gc->of_node = np;
gc->owner = THIS_MODULE;
gc->label = np->full_name;
gc->base = -1;
err = of_property_read_u32(np, "nbits", &prop);
if (err || prop <= 0 || prop > GRGPIO_MAX_NGPIO) {
gc->ngpio = GRGPIO_MAX_NGPIO;
dev_dbg(&ofdev->dev,
"No or invalid nbits property: assume %d\n", gc->ngpio);
} else {
gc->ngpio = prop;
}
platform_set_drvdata(ofdev, priv);
err = gpiochip_add(gc);
if (err) {
dev_err(&ofdev->dev, "Could not add gpiochip\n");
return err;
}
dev_info(&ofdev->dev, "regs=0x%p, base=%d, ngpio=%d\n",
priv->regs, gc->base, gc->ngpio);
return 0;
}
static int grgpio_remove(struct platform_device *ofdev)
{
struct grgpio_priv *priv = platform_get_drvdata(ofdev);
return gpiochip_remove(&priv->bgc.gc);
}
static struct of_device_id grgpio_match[] = {
{.name = "GAISLER_GPIO"},
{.name = "01_01a"},
{},
};
MODULE_DEVICE_TABLE(of, grgpio_match);
static struct platform_driver grgpio_driver = {
.driver = {
.name = "grgpio",
.owner = THIS_MODULE,
.of_match_table = grgpio_match,
},
.probe = grgpio_probe,
.remove = grgpio_remove,
};
module_platform_driver(grgpio_driver);
MODULE_AUTHOR("Aeroflex Gaisler AB.");
MODULE_DESCRIPTION("Driver for Aeroflex Gaisler GRGPIO");
MODULE_LICENSE("GPL");
