kernel-aes67/drivers/gpio/gpio-ge.c

100 lines
2.4 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Driver for GE FPGA based GPIO
*
* Author: Martyn Welch <martyn.welch@ge.com>
*
* 2008 (c) GE Intelligent Platforms Embedded Systems, Inc.
*/
/*
* TODO:
*
* Configuration of output modes (totem-pole/open-drain).
* Interrupt configuration - interrupts are always generated, the FPGA relies
* on the I/O interrupt controllers mask to stop them from being propagated.
*/
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/slab.h>
#define GEF_GPIO_DIRECT 0x00
#define GEF_GPIO_IN 0x04
#define GEF_GPIO_OUT 0x08
#define GEF_GPIO_TRIG 0x0C
#define GEF_GPIO_POLAR_A 0x10
#define GEF_GPIO_POLAR_B 0x14
#define GEF_GPIO_INT_STAT 0x18
#define GEF_GPIO_OVERRUN 0x1C
#define GEF_GPIO_MODE 0x20
static const struct of_device_id gef_gpio_ids[] = {
{
.compatible = "gef,sbc610-gpio",
.data = (void *)19,
}, {
.compatible = "gef,sbc310-gpio",
.data = (void *)6,
}, {
.compatible = "ge,imp3a-gpio",
.data = (void *)16,
},
{ }
};
MODULE_DEVICE_TABLE(of, gef_gpio_ids);
static int __init gef_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct gpio_chip *gc;
void __iomem *regs;
int ret;
gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
if (!gc)
return -ENOMEM;
regs = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(regs))
return PTR_ERR(regs);
ret = bgpio_init(gc, dev, 4, regs + GEF_GPIO_IN, regs + GEF_GPIO_OUT,
NULL, NULL, regs + GEF_GPIO_DIRECT,
BGPIOF_BIG_ENDIAN_BYTE_ORDER);
if (ret)
return dev_err_probe(dev, ret, "bgpio_init failed\n");
/* Setup pointers to chip functions */
gc->label = devm_kasprintf(dev, GFP_KERNEL, "%pfw", dev_fwnode(dev));
if (!gc->label)
return -ENOMEM;
gc->base = -1;
gc->ngpio = (uintptr_t)device_get_match_data(dev);
/* This function adds a memory mapped GPIO chip */
ret = devm_gpiochip_add_data(dev, gc, NULL);
if (ret)
return dev_err_probe(dev, ret, "GPIO chip registration failed\n");
return 0;
};
static struct platform_driver gef_gpio_driver = {
.driver = {
.name = "gef-gpio",
.of_match_table = gef_gpio_ids,
},
};
module_platform_driver_probe(gef_gpio_driver, gef_gpio_probe);
MODULE_DESCRIPTION("GE I/O FPGA GPIO driver");
MODULE_AUTHOR("Martyn Welch <martyn.welch@ge.com>");
MODULE_LICENSE("GPL");