Re[2]: [RFC] Add Generic GPIO driver
Alexander Shiyan
shc_work at mail.ru
Mon Feb 18 05:13:22 EST 2013
> On Fri, Feb 15, 2013 at 10:49:27PM +0400, Alexander Shiyan wrote:
> > This patch adds generic memory-mapped GPIO controller support.
> > Code taken from Linux Kernel and adopted for barebox.
>
> I'm fine with this if you add a user for it. I wonder though if it's
> worth it to have this driver for barebox. If I have a driver in the
> kernel that already uses it, then this makes it simple to copy it, but
> should I have to write a new gpio driver, I'm unsure if it's simpler
> to write a new gpio driver or to register with the generic gpio
> driver.
Here's an example that I'm checking:
/*
* Copyright (C) 2013 Alexander Shiyan <shc_work at mail.ru>
*
* 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 <init.h>
#include <common.h>
#include <malloc.h>
#include <linux/basic_mmio_gpio.h>
static int clps711x_gpio_probe(struct device_d *dev)
{
int err;
void __iomem *dat, *dir, *dir_inv;
struct bgpio_chip *bgc;
struct bgpio_pdata *pdata = dev->platform_data;
if (!pdata)
return -ENODATA;
dat = dev_request_mem_region_by_name(dev, "dat");
dir = dev_request_mem_region_by_name(dev, "dir");
dir_inv = dev_request_mem_region_by_name(dev, "dir_inv");
if (!dat || (!dir && !dir_inv))
return -EINVAL;
bgc = xzalloc(sizeof(struct bgpio_chip));
if (!bgc)
return -ENOMEM;
err = bgpio_init(bgc, dev, 1, dat, NULL, NULL, dir, dir_inv, 0);
if (err) {
free(bgc);
return err;
}
bgc->gc.base = pdata->base;
bgc->gc.ngpio = pdata->ngpio;
return gpiochip_add(&bgc->gc);
}
static struct driver_d clps711x_gpio_driver = {
.name = "clps711x-gpio",
.probe = clps711x_gpio_probe,
};
static __init int clps711x_gpio_register(void)
{
return platform_driver_register(&clps711x_gpio_driver);
}
coredevice_initcall(clps711x_gpio_register);
---
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