swh:1:snp:49cd9498d6cccc5e78252c27dcb645bcf7bf0c91
Tip revision: 9e82bf014195d6f0054982c463575cdce24292be authored by Linus Torvalds on 15 September 2014, 00:50:12 UTC
Linux 3.17-rc5
Linux 3.17-rc5
Tip revision: 9e82bf0
gpio-dwapb.c
/*
* 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)
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");