alistair23-linux/drivers/gpio/gpio-timberdale.c
Thomas Gleixner 82c298100a treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 176
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 version 2 as
  published by the free software foundation 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-only

has been chosen to replace the boilerplate/reference in 44 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Steve Winslow <swinslow@gmail.com>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170025.980374610@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:29:19 -07:00

290 lines
6.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Timberdale FPGA GPIO driver
* Author: Mocean Laboratories
* Copyright (c) 2009 Intel Corporation
*/
/* Supports:
* Timberdale FPGA GPIO
*/
#include <linux/init.h>
#include <linux/gpio/driver.h>
#include <linux/platform_device.h>
#include <linux/irq.h>
#include <linux/io.h>
#include <linux/timb_gpio.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#define DRIVER_NAME "timb-gpio"
#define TGPIOVAL 0x00
#define TGPIODIR 0x04
#define TGPIO_IER 0x08
#define TGPIO_ISR 0x0c
#define TGPIO_IPR 0x10
#define TGPIO_ICR 0x14
#define TGPIO_FLR 0x18
#define TGPIO_LVR 0x1c
#define TGPIO_VER 0x20
#define TGPIO_BFLR 0x24
struct timbgpio {
void __iomem *membase;
spinlock_t lock; /* mutual exclusion */
struct gpio_chip gpio;
int irq_base;
unsigned long last_ier;
};
static int timbgpio_update_bit(struct gpio_chip *gpio, unsigned index,
unsigned offset, bool enabled)
{
struct timbgpio *tgpio = gpiochip_get_data(gpio);
u32 reg;
spin_lock(&tgpio->lock);
reg = ioread32(tgpio->membase + offset);
if (enabled)
reg |= (1 << index);
else
reg &= ~(1 << index);
iowrite32(reg, tgpio->membase + offset);
spin_unlock(&tgpio->lock);
return 0;
}
static int timbgpio_gpio_direction_input(struct gpio_chip *gpio, unsigned nr)
{
return timbgpio_update_bit(gpio, nr, TGPIODIR, true);
}
static int timbgpio_gpio_get(struct gpio_chip *gpio, unsigned nr)
{
struct timbgpio *tgpio = gpiochip_get_data(gpio);
u32 value;
value = ioread32(tgpio->membase + TGPIOVAL);
return (value & (1 << nr)) ? 1 : 0;
}
static int timbgpio_gpio_direction_output(struct gpio_chip *gpio,
unsigned nr, int val)
{
return timbgpio_update_bit(gpio, nr, TGPIODIR, false);
}
static void timbgpio_gpio_set(struct gpio_chip *gpio,
unsigned nr, int val)
{
timbgpio_update_bit(gpio, nr, TGPIOVAL, val != 0);
}
static int timbgpio_to_irq(struct gpio_chip *gpio, unsigned offset)
{
struct timbgpio *tgpio = gpiochip_get_data(gpio);
if (tgpio->irq_base <= 0)
return -EINVAL;
return tgpio->irq_base + offset;
}
/*
* GPIO IRQ
*/
static void timbgpio_irq_disable(struct irq_data *d)
{
struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
int offset = d->irq - tgpio->irq_base;
unsigned long flags;
spin_lock_irqsave(&tgpio->lock, flags);
tgpio->last_ier &= ~(1UL << offset);
iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
spin_unlock_irqrestore(&tgpio->lock, flags);
}
static void timbgpio_irq_enable(struct irq_data *d)
{
struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
int offset = d->irq - tgpio->irq_base;
unsigned long flags;
spin_lock_irqsave(&tgpio->lock, flags);
tgpio->last_ier |= 1UL << offset;
iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
spin_unlock_irqrestore(&tgpio->lock, flags);
}
static int timbgpio_irq_type(struct irq_data *d, unsigned trigger)
{
struct timbgpio *tgpio = irq_data_get_irq_chip_data(d);
int offset = d->irq - tgpio->irq_base;
unsigned long flags;
u32 lvr, flr, bflr = 0;
u32 ver;
int ret = 0;
if (offset < 0 || offset > tgpio->gpio.ngpio)
return -EINVAL;
ver = ioread32(tgpio->membase + TGPIO_VER);
spin_lock_irqsave(&tgpio->lock, flags);
lvr = ioread32(tgpio->membase + TGPIO_LVR);
flr = ioread32(tgpio->membase + TGPIO_FLR);
if (ver > 2)
bflr = ioread32(tgpio->membase + TGPIO_BFLR);
if (trigger & (IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW)) {
bflr &= ~(1 << offset);
flr &= ~(1 << offset);
if (trigger & IRQ_TYPE_LEVEL_HIGH)
lvr |= 1 << offset;
else
lvr &= ~(1 << offset);
}
if ((trigger & IRQ_TYPE_EDGE_BOTH) == IRQ_TYPE_EDGE_BOTH) {
if (ver < 3) {
ret = -EINVAL;
goto out;
} else {
flr |= 1 << offset;
bflr |= 1 << offset;
}
} else {
bflr &= ~(1 << offset);
flr |= 1 << offset;
if (trigger & IRQ_TYPE_EDGE_FALLING)
lvr &= ~(1 << offset);
else
lvr |= 1 << offset;
}
iowrite32(lvr, tgpio->membase + TGPIO_LVR);
iowrite32(flr, tgpio->membase + TGPIO_FLR);
if (ver > 2)
iowrite32(bflr, tgpio->membase + TGPIO_BFLR);
iowrite32(1 << offset, tgpio->membase + TGPIO_ICR);
out:
spin_unlock_irqrestore(&tgpio->lock, flags);
return ret;
}
static void timbgpio_irq(struct irq_desc *desc)
{
struct timbgpio *tgpio = irq_desc_get_handler_data(desc);
struct irq_data *data = irq_desc_get_irq_data(desc);
unsigned long ipr;
int offset;
data->chip->irq_ack(data);
ipr = ioread32(tgpio->membase + TGPIO_IPR);
iowrite32(ipr, tgpio->membase + TGPIO_ICR);
/*
* Some versions of the hardware trash the IER register if more than
* one interrupt is received simultaneously.
*/
iowrite32(0, tgpio->membase + TGPIO_IER);
for_each_set_bit(offset, &ipr, tgpio->gpio.ngpio)
generic_handle_irq(timbgpio_to_irq(&tgpio->gpio, offset));
iowrite32(tgpio->last_ier, tgpio->membase + TGPIO_IER);
}
static struct irq_chip timbgpio_irqchip = {
.name = "GPIO",
.irq_enable = timbgpio_irq_enable,
.irq_disable = timbgpio_irq_disable,
.irq_set_type = timbgpio_irq_type,
};
static int timbgpio_probe(struct platform_device *pdev)
{
int err, i;
struct device *dev = &pdev->dev;
struct gpio_chip *gc;
struct timbgpio *tgpio;
struct timbgpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
int irq = platform_get_irq(pdev, 0);
if (!pdata || pdata->nr_pins > 32) {
dev_err(dev, "Invalid platform data\n");
return -EINVAL;
}
tgpio = devm_kzalloc(dev, sizeof(*tgpio), GFP_KERNEL);
if (!tgpio)
return -EINVAL;
tgpio->irq_base = pdata->irq_base;
spin_lock_init(&tgpio->lock);
tgpio->membase = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(tgpio->membase))
return PTR_ERR(tgpio->membase);
gc = &tgpio->gpio;
gc->label = dev_name(&pdev->dev);
gc->owner = THIS_MODULE;
gc->parent = &pdev->dev;
gc->direction_input = timbgpio_gpio_direction_input;
gc->get = timbgpio_gpio_get;
gc->direction_output = timbgpio_gpio_direction_output;
gc->set = timbgpio_gpio_set;
gc->to_irq = (irq >= 0 && tgpio->irq_base > 0) ? timbgpio_to_irq : NULL;
gc->dbg_show = NULL;
gc->base = pdata->gpio_base;
gc->ngpio = pdata->nr_pins;
gc->can_sleep = false;
err = devm_gpiochip_add_data(&pdev->dev, gc, tgpio);
if (err)
return err;
platform_set_drvdata(pdev, tgpio);
/* make sure to disable interrupts */
iowrite32(0x0, tgpio->membase + TGPIO_IER);
if (irq < 0 || tgpio->irq_base <= 0)
return 0;
for (i = 0; i < pdata->nr_pins; i++) {
irq_set_chip_and_handler(tgpio->irq_base + i,
&timbgpio_irqchip, handle_simple_irq);
irq_set_chip_data(tgpio->irq_base + i, tgpio);
irq_clear_status_flags(tgpio->irq_base + i, IRQ_NOREQUEST | IRQ_NOPROBE);
}
irq_set_chained_handler_and_data(irq, timbgpio_irq, tgpio);
return 0;
}
static struct platform_driver timbgpio_platform_driver = {
.driver = {
.name = DRIVER_NAME,
.suppress_bind_attrs = true,
},
.probe = timbgpio_probe,
};
/*--------------------------------------------------------------------------*/
builtin_platform_driver(timbgpio_platform_driver);