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alistair23-linux/drivers/gpio/gpio-dwapb.c
Sebastian Andrzej Siewior 6a2f4b7dad gpio: dwapb: use a second irq chip 
Right new have one irq chip running always in level mode. It would nicer
to have two irq chips where one is handling level type interrupts and
the other one is doing edge interrupts. So we can have at runtime two users
where one is using edge and the other level.

Acked-by: Alan Tull <delicious.quinoa@gmail.com>
Acked-by: Jamie Iles <jamie@jamieiles.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-05-27 16:20:34 +02:00

445 lines
11 KiB
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/*
* Copyright (c) 2011 Jamie Iles
*
* 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.
*
* All enquiries to support@picochip.com
*/
#include <linux/basic_mmio_gpio.h>
#include <linux/err.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#define GPIO_SWPORTA_DR 0x00
#define GPIO_SWPORTA_DDR 0x04
#define GPIO_SWPORTB_DR 0x0c
#define GPIO_SWPORTB_DDR 0x10
#define GPIO_SWPORTC_DR 0x18
#define GPIO_SWPORTC_DDR 0x1c
#define GPIO_SWPORTD_DR 0x24
#define GPIO_SWPORTD_DDR 0x28
#define GPIO_INTEN 0x30
#define GPIO_INTMASK 0x34
#define GPIO_INTTYPE_LEVEL 0x38
#define GPIO_INT_POLARITY 0x3c
#define GPIO_INTSTATUS 0x40
#define GPIO_PORTA_EOI 0x4c
#define GPIO_EXT_PORTA 0x50
#define GPIO_EXT_PORTB 0x54
#define GPIO_EXT_PORTC 0x58
#define GPIO_EXT_PORTD 0x5c
#define DWAPB_MAX_PORTS 4
#define GPIO_EXT_PORT_SIZE (GPIO_EXT_PORTB - GPIO_EXT_PORTA)
#define GPIO_SWPORT_DR_SIZE (GPIO_SWPORTB_DR - GPIO_SWPORTA_DR)
#define GPIO_SWPORT_DDR_SIZE (GPIO_SWPORTB_DDR - GPIO_SWPORTA_DDR)
struct dwapb_gpio;
struct dwapb_gpio_port {
struct bgpio_chip bgc;
bool is_registered;
struct dwapb_gpio *gpio;
};
struct dwapb_gpio {
struct device *dev;
void __iomem *regs;
struct dwapb_gpio_port *ports;
unsigned int nr_ports;
struct irq_domain *domain;
};
static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
{
struct bgpio_chip *bgc = to_bgpio_chip(gc);
struct dwapb_gpio_port *port = container_of(bgc, struct
dwapb_gpio_port, bgc);
struct dwapb_gpio *gpio = port->gpio;
return irq_find_mapping(gpio->domain, offset);
}
static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
{
u32 v = readl(gpio->regs + GPIO_INT_POLARITY);
if (gpio_get_value(gpio->ports[0].bgc.gc.base + offs))
v &= ~BIT(offs);
else
v |= BIT(offs);
writel(v, gpio->regs + GPIO_INT_POLARITY);
}
static void dwapb_irq_handler(u32 irq, struct irq_desc *desc)
{
struct dwapb_gpio *gpio = irq_get_handler_data(irq);
struct irq_chip *chip = irq_desc_get_chip(desc);
u32 irq_status = readl_relaxed(gpio->regs + GPIO_INTSTATUS);
while (irq_status) {
int hwirq = fls(irq_status) - 1;
int gpio_irq = irq_find_mapping(gpio->domain, hwirq);
generic_handle_irq(gpio_irq);
irq_status &= ~BIT(hwirq);
if ((irq_get_trigger_type(gpio_irq) & IRQ_TYPE_SENSE_MASK)
== IRQ_TYPE_EDGE_BOTH)
dwapb_toggle_trigger(gpio, hwirq);
}
if (chip->irq_eoi)
chip->irq_eoi(irq_desc_get_irq_data(desc));
}
static void dwapb_irq_enable(struct irq_data *d)
{
struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
struct dwapb_gpio *gpio = igc->private;
struct bgpio_chip *bgc = &gpio->ports[0].bgc;
unsigned long flags;
u32 val;
spin_lock_irqsave(&bgc->lock, flags);
val = readl(gpio->regs + GPIO_INTEN);
val |= BIT(d->hwirq);
writel(val, gpio->regs + GPIO_INTEN);
spin_unlock_irqrestore(&bgc->lock, flags);
}
static void dwapb_irq_disable(struct irq_data *d)
{
struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
struct dwapb_gpio *gpio = igc->private;
struct bgpio_chip *bgc = &gpio->ports[0].bgc;
unsigned long flags;
u32 val;
spin_lock_irqsave(&bgc->lock, flags);
val = readl(gpio->regs + GPIO_INTEN);
val &= ~BIT(d->hwirq);
writel(val, gpio->regs + GPIO_INTEN);
spin_unlock_irqrestore(&bgc->lock, flags);
}
static int dwapb_irq_reqres(struct irq_data *d)
{
struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
struct dwapb_gpio *gpio = igc->private;
struct bgpio_chip *bgc = &gpio->ports[0].bgc;
if (gpio_lock_as_irq(&bgc->gc, irqd_to_hwirq(d))) {
dev_err(gpio->dev, "unable to lock HW IRQ %lu for IRQ\n",
irqd_to_hwirq(d));
return -EINVAL;
}
return 0;
}
static void dwapb_irq_relres(struct irq_data *d)
{
struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
struct dwapb_gpio *gpio = igc->private;
struct bgpio_chip *bgc = &gpio->ports[0].bgc;
gpio_unlock_as_irq(&bgc->gc, irqd_to_hwirq(d));
}
static int dwapb_irq_set_type(struct irq_data *d, u32 type)
{
struct irq_chip_generic *igc = irq_data_get_irq_chip_data(d);
struct dwapb_gpio *gpio = igc->private;
struct bgpio_chip *bgc = &gpio->ports[0].bgc;
int bit = d->hwirq;
unsigned long level, polarity, flags;
if (type & ~(IRQ_TYPE_EDGE_RISING | IRQ_TYPE_EDGE_FALLING |
IRQ_TYPE_LEVEL_HIGH | IRQ_TYPE_LEVEL_LOW))
return -EINVAL;
spin_lock_irqsave(&bgc->lock, flags);
level = readl(gpio->regs + GPIO_INTTYPE_LEVEL);
polarity = readl(gpio->regs + GPIO_INT_POLARITY);
switch (type) {
case IRQ_TYPE_EDGE_BOTH:
level |= BIT(bit);
dwapb_toggle_trigger(gpio, bit);
break;
case IRQ_TYPE_EDGE_RISING:
level |= BIT(bit);
polarity |= BIT(bit);
break;
case IRQ_TYPE_EDGE_FALLING:
level |= BIT(bit);
polarity &= ~BIT(bit);
break;
case IRQ_TYPE_LEVEL_HIGH:
level &= ~BIT(bit);
polarity |= BIT(bit);
break;
case IRQ_TYPE_LEVEL_LOW:
level &= ~BIT(bit);
polarity &= ~BIT(bit);
break;
}
irq_setup_alt_chip(d, type);
writel(level, gpio->regs + GPIO_INTTYPE_LEVEL);
writel(polarity, gpio->regs + GPIO_INT_POLARITY);
spin_unlock_irqrestore(&bgc->lock, flags);
return 0;
}
static void dwapb_configure_irqs(struct dwapb_gpio *gpio,
struct dwapb_gpio_port *port)
{
struct gpio_chip *gc = &port->bgc.gc;
struct device_node *node = gc->of_node;
struct irq_chip_generic *irq_gc;
unsigned int hwirq, ngpio = gc->ngpio;
struct irq_chip_type *ct;
int err, irq, i;
irq = irq_of_parse_and_map(node, 0);
if (!irq) {
dev_warn(gpio->dev, "no irq for bank %s\n",
port->bgc.gc.of_node->full_name);
return;
}
gpio->domain = irq_domain_add_linear(node, ngpio,
&irq_generic_chip_ops, gpio);
if (!gpio->domain)
return;
err = irq_alloc_domain_generic_chips(gpio->domain, ngpio, 2,
"gpio-dwapb", handle_level_irq,
IRQ_NOREQUEST, 0,
IRQ_GC_INIT_NESTED_LOCK);
if (err) {
dev_info(gpio->dev, "irq_alloc_domain_generic_chips failed\n");
irq_domain_remove(gpio->domain);
gpio->domain = NULL;
return;
}
irq_gc = irq_get_domain_generic_chip(gpio->domain, 0);
if (!irq_gc) {
irq_domain_remove(gpio->domain);
gpio->domain = NULL;
return;
}
irq_gc->reg_base = gpio->regs;
irq_gc->private = gpio;
for (i = 0; i < 2; i++) {
ct = &irq_gc->chip_types[i];
ct->chip.irq_ack = irq_gc_ack_set_bit;
ct->chip.irq_mask = irq_gc_mask_set_bit;
ct->chip.irq_unmask = irq_gc_mask_clr_bit;
ct->chip.irq_set_type = dwapb_irq_set_type;
ct->chip.irq_enable = dwapb_irq_enable;
ct->chip.irq_disable = dwapb_irq_disable;
ct->chip.irq_request_resources = dwapb_irq_reqres;
ct->chip.irq_release_resources = dwapb_irq_relres;
ct->regs.ack = GPIO_PORTA_EOI;
ct->regs.mask = GPIO_INTMASK;
ct->type = IRQ_TYPE_LEVEL_MASK;
}
irq_gc->chip_types[0].type = IRQ_TYPE_LEVEL_MASK;
irq_gc->chip_types[1].type = IRQ_TYPE_EDGE_BOTH;
irq_gc->chip_types[1].handler = handle_edge_irq;
irq_set_chained_handler(irq, dwapb_irq_handler);
irq_set_handler_data(irq, gpio);
for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
irq_create_mapping(gpio->domain, hwirq);
port->bgc.gc.to_irq = dwapb_gpio_to_irq;
}
static void dwapb_irq_teardown(struct dwapb_gpio *gpio)
{
struct dwapb_gpio_port *port = &gpio->ports[0];
struct gpio_chip *gc = &port->bgc.gc;
unsigned int ngpio = gc->ngpio;
irq_hw_number_t hwirq;
if (!gpio->domain)
return;
for (hwirq = 0 ; hwirq < ngpio ; hwirq++)
irq_dispose_mapping(irq_find_mapping(gpio->domain, hwirq));
irq_domain_remove(gpio->domain);
gpio->domain = NULL;
}
static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
struct device_node *port_np,
unsigned int offs)
{
struct dwapb_gpio_port *port;
u32 port_idx, ngpio;
void __iomem *dat, *set, *dirout;
int err;
if (of_property_read_u32(port_np, "reg", &port_idx) ||
port_idx >= DWAPB_MAX_PORTS) {
dev_err(gpio->dev, "missing/invalid port index for %s\n",
port_np->full_name);
return -EINVAL;
}
port = &gpio->ports[offs];
port->gpio = gpio;
if (of_property_read_u32(port_np, "snps,nr-gpios", &ngpio)) {
dev_info(gpio->dev, "failed to get number of gpios for %s\n",
port_np->full_name);
ngpio = 32;
}
dat = gpio->regs + GPIO_EXT_PORTA + (port_idx * GPIO_EXT_PORT_SIZE);
set = gpio->regs + GPIO_SWPORTA_DR + (port_idx * GPIO_SWPORT_DR_SIZE);
dirout = gpio->regs + GPIO_SWPORTA_DDR +
(port_idx * GPIO_SWPORT_DDR_SIZE);
err = bgpio_init(&port->bgc, gpio->dev, 4, dat, set, NULL, dirout,
NULL, false);
if (err) {
dev_err(gpio->dev, "failed to init gpio chip for %s\n",
port_np->full_name);
return err;
}
port->bgc.gc.ngpio = ngpio;
port->bgc.gc.of_node = port_np;
/*
* Only port A can provide interrupts in all configurations of the IP.
*/
if (port_idx == 0 &&
of_property_read_bool(port_np, "interrupt-controller"))
dwapb_configure_irqs(gpio, port);
err = gpiochip_add(&port->bgc.gc);
if (err)
dev_err(gpio->dev, "failed to register gpiochip for %s\n",
port_np->full_name);
else
port->is_registered = true;
return err;
}
static void dwapb_gpio_unregister(struct dwapb_gpio *gpio)
{
unsigned int m;
for (m = 0; m < gpio->nr_ports; ++m)
if (gpio->ports[m].is_registered)
WARN_ON(gpiochip_remove(&gpio->ports[m].bgc.gc));
}
static int dwapb_gpio_probe(struct platform_device *pdev)
{
struct resource *res;
struct dwapb_gpio *gpio;
struct device_node *np;
int err;
unsigned int offs = 0;
gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
if (!gpio)
return -ENOMEM;
gpio->dev = &pdev->dev;
gpio->nr_ports = of_get_child_count(pdev->dev.of_node);
if (!gpio->nr_ports) {
err = -EINVAL;
goto out_err;
}
gpio->ports = devm_kzalloc(&pdev->dev, gpio->nr_ports *
sizeof(*gpio->ports), GFP_KERNEL);
if (!gpio->ports) {
err = -ENOMEM;
goto out_err;
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
gpio->regs = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(gpio->regs)) {
err = PTR_ERR(gpio->regs);
goto out_err;
}
for_each_child_of_node(pdev->dev.of_node, np) {
err = dwapb_gpio_add_port(gpio, np, offs++);
if (err)
goto out_unregister;
}
platform_set_drvdata(pdev, gpio);
return 0;
out_unregister:
dwapb_gpio_unregister(gpio);
dwapb_irq_teardown(gpio);
out_err:
return err;
}
static int dwapb_gpio_remove(struct platform_device *pdev)
{
struct dwapb_gpio *gpio = platform_get_drvdata(pdev);
dwapb_gpio_unregister(gpio);
dwapb_irq_teardown(gpio);
return 0;
}
static const struct of_device_id dwapb_of_match[] = {
{ .compatible = "snps,dw-apb-gpio" },
{ /* Sentinel */ }
};
MODULE_DEVICE_TABLE(of, dwapb_of_match);
static struct platform_driver dwapb_gpio_driver = {
.driver = {
.name = "gpio-dwapb",
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(dwapb_of_match),
},
.probe = dwapb_gpio_probe,
.remove = dwapb_gpio_remove,
};
module_platform_driver(dwapb_gpio_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Jamie Iles");
MODULE_DESCRIPTION("Synopsys DesignWare APB GPIO driver");
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