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linux/drivers/gpio/gpio-rdc321x.c
Thomas Gleixner 74ba9207e1 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 61
Based on 1 normalized pattern(s):

  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 this program is distributed in the
  hope that it will be useful but without any warranty without even
  the implied warranty of merchantability or fitness for a particular
  purpose see the gnu general public license for more details you
  should have received a copy of the gnu general public license along
  with this program if not write to the free software foundation inc
  675 mass ave cambridge ma 02139 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 441 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190520071858.739733335@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-24 17:36:45 +02:00

198 lines
5.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* RDC321x GPIO driver
*
* Copyright (C) 2008, Volker Weiss <dev@tintuc.de>
* Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <linux/gpio/driver.h>
#include <linux/mfd/rdc321x.h>
#include <linux/slab.h>
struct rdc321x_gpio {
spinlock_t lock;
struct pci_dev *sb_pdev;
u32 data_reg[2];
int reg1_ctrl_base;
int reg1_data_base;
int reg2_ctrl_base;
int reg2_data_base;
struct gpio_chip chip;
};
/* read GPIO pin */
static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
struct rdc321x_gpio *gpch;
u32 value = 0;
int reg;
gpch = gpiochip_get_data(chip);
reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
spin_lock(&gpch->lock);
pci_write_config_dword(gpch->sb_pdev, reg,
gpch->data_reg[gpio < 32 ? 0 : 1]);
pci_read_config_dword(gpch->sb_pdev, reg, &value);
spin_unlock(&gpch->lock);
return (1 << (gpio & 0x1f)) & value ? 1 : 0;
}
static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct rdc321x_gpio *gpch;
int reg = (gpio < 32) ? 0 : 1;
gpch = gpiochip_get_data(chip);
if (value)
gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
else
gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
pci_write_config_dword(gpch->sb_pdev,
reg ? gpch->reg2_data_base : gpch->reg1_data_base,
gpch->data_reg[reg]);
}
/* set GPIO pin to value */
static void rdc_gpio_set_value(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct rdc321x_gpio *gpch;
gpch = gpiochip_get_data(chip);
spin_lock(&gpch->lock);
rdc_gpio_set_value_impl(chip, gpio, value);
spin_unlock(&gpch->lock);
}
static int rdc_gpio_config(struct gpio_chip *chip,
unsigned gpio, int value)
{
struct rdc321x_gpio *gpch;
int err;
u32 reg;
gpch = gpiochip_get_data(chip);
spin_lock(&gpch->lock);
err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
if (err)
goto unlock;
reg |= 1 << (gpio & 0x1f);
err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
if (err)
goto unlock;
rdc_gpio_set_value_impl(chip, gpio, value);
unlock:
spin_unlock(&gpch->lock);
return err;
}
/* configure GPIO pin as input */
static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
return rdc_gpio_config(chip, gpio, 1);
}
/*
* Cache the initial value of both GPIO data registers
*/
static int rdc321x_gpio_probe(struct platform_device *pdev)
{
int err;
struct resource *r;
struct rdc321x_gpio *rdc321x_gpio_dev;
struct rdc321x_gpio_pdata *pdata;
pdata = dev_get_platdata(&pdev->dev);
if (!pdata) {
dev_err(&pdev->dev, "no platform data supplied\n");
return -ENODEV;
}
rdc321x_gpio_dev = devm_kzalloc(&pdev->dev, sizeof(struct rdc321x_gpio),
GFP_KERNEL);
if (!rdc321x_gpio_dev)
return -ENOMEM;
r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
if (!r) {
dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
return -ENODEV;
}
spin_lock_init(&rdc321x_gpio_dev->lock);
rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
rdc321x_gpio_dev->reg1_ctrl_base = r->start;
rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
if (!r) {
dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
return -ENODEV;
}
rdc321x_gpio_dev->reg2_ctrl_base = r->start;
rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
rdc321x_gpio_dev->chip.owner = THIS_MODULE;
rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
rdc321x_gpio_dev->chip.base = 0;
rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;
platform_set_drvdata(pdev, rdc321x_gpio_dev);
/* This might not be, what others (BIOS, bootloader, etc.)
wrote to these registers before, but it's a good guess. Still
better than just using 0xffffffff. */
err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
rdc321x_gpio_dev->reg1_data_base,
&rdc321x_gpio_dev->data_reg[0]);
if (err)
return err;
err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
rdc321x_gpio_dev->reg2_data_base,
&rdc321x_gpio_dev->data_reg[1]);
if (err)
return err;
dev_info(&pdev->dev, "registering %d GPIOs\n",
rdc321x_gpio_dev->chip.ngpio);
return devm_gpiochip_add_data(&pdev->dev, &rdc321x_gpio_dev->chip,
rdc321x_gpio_dev);
}
static struct platform_driver rdc321x_gpio_driver = {
.driver.name = "rdc321x-gpio",
.probe = rdc321x_gpio_probe,
};
module_platform_driver(rdc321x_gpio_driver);
MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
MODULE_DESCRIPTION("RDC321x GPIO driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:rdc321x-gpio");