linux/drivers/gpio/gpio-ge.c

115 lines
2.7 KiB
C

/*
* Driver for GE FPGA based GPIO
*
* Author: Martyn Welch <martyn.welch@ge.com>
*
* 2008 (c) GE Intelligent Platforms Embedded Systems, Inc.
*
* This file is licensed under the terms of the GNU General Public License
* version 2. This program is licensed "as is" without any warranty of any
* kind, whether express or implied.
*/
/* 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 propergating
*/
#include <linux/kernel.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/of_address.h>
#include <linux/module.h>
#include <linux/gpio/driver.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)
{
const struct of_device_id *of_id =
of_match_device(gef_gpio_ids, &pdev->dev);
struct gpio_chip *gc;
void __iomem *regs;
int ret;
gc = devm_kzalloc(&pdev->dev, sizeof(*gc), GFP_KERNEL);
if (!gc)
return -ENOMEM;
regs = of_iomap(pdev->dev.of_node, 0);
if (!regs)
return -ENOMEM;
ret = bgpio_init(gc, &pdev->dev, 4, regs + GEF_GPIO_IN,
regs + GEF_GPIO_OUT, NULL, NULL,
regs + GEF_GPIO_DIRECT, BGPIOF_BIG_ENDIAN_BYTE_ORDER);
if (ret) {
dev_err(&pdev->dev, "bgpio_init failed\n");
goto err0;
}
/* Setup pointers to chip functions */
gc->label = devm_kstrdup(&pdev->dev, pdev->dev.of_node->full_name,
GFP_KERNEL);
if (!gc->label) {
ret = -ENOMEM;
goto err0;
}
gc->base = -1;
gc->ngpio = (u16)(uintptr_t)of_id->data;
gc->of_gpio_n_cells = 2;
gc->of_node = pdev->dev.of_node;
/* This function adds a memory mapped GPIO chip */
ret = devm_gpiochip_add_data(&pdev->dev, gc, NULL);
if (ret)
goto err0;
return 0;
err0:
iounmap(regs);
pr_err("%s: GPIO chip registration failed\n",
pdev->dev.of_node->full_name);
return ret;
};
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");