Revision 9f8933e960f98d27742727445061b0ece934e5cf authored by John W. Linville on 30 November 2012, 16:27:32 UTC, committed by John W. Linville on 30 November 2012, 16:27:32 UTC
gpio-em.c
/*
* Emma Mobile GPIO Support - GIO
*
* Copyright (C) 2012 Magnus Damm
*
* 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
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/platform_data/gpio-em.h>
struct em_gio_priv {
void __iomem *base0;
void __iomem *base1;
unsigned int irq_base;
spinlock_t sense_lock;
struct platform_device *pdev;
struct gpio_chip gpio_chip;
struct irq_chip irq_chip;
struct irq_domain *irq_domain;
};
#define GIO_E1 0x00
#define GIO_E0 0x04
#define GIO_EM 0x04
#define GIO_OL 0x08
#define GIO_OH 0x0c
#define GIO_I 0x10
#define GIO_IIA 0x14
#define GIO_IEN 0x18
#define GIO_IDS 0x1c
#define GIO_IIM 0x1c
#define GIO_RAW 0x20
#define GIO_MST 0x24
#define GIO_IIR 0x28
#define GIO_IDT0 0x40
#define GIO_IDT1 0x44
#define GIO_IDT2 0x48
#define GIO_IDT3 0x4c
#define GIO_RAWBL 0x50
#define GIO_RAWBH 0x54
#define GIO_IRBL 0x58
#define GIO_IRBH 0x5c
#define GIO_IDT(n) (GIO_IDT0 + ((n) * 4))
static inline unsigned long em_gio_read(struct em_gio_priv *p, int offs)
{
if (offs < GIO_IDT0)
return ioread32(p->base0 + offs);
else
return ioread32(p->base1 + (offs - GIO_IDT0));
}
static inline void em_gio_write(struct em_gio_priv *p, int offs,
unsigned long value)
{
if (offs < GIO_IDT0)
iowrite32(value, p->base0 + offs);
else
iowrite32(value, p->base1 + (offs - GIO_IDT0));
}
static void em_gio_irq_disable(struct irq_data *d)
{
struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
em_gio_write(p, GIO_IDS, BIT(irqd_to_hwirq(d)));
}
static void em_gio_irq_enable(struct irq_data *d)
{
struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
em_gio_write(p, GIO_IEN, BIT(irqd_to_hwirq(d)));
}
#define GIO_ASYNC(x) (x + 8)
static unsigned char em_gio_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
[IRQ_TYPE_EDGE_RISING] = GIO_ASYNC(0x00),
[IRQ_TYPE_EDGE_FALLING] = GIO_ASYNC(0x01),
[IRQ_TYPE_LEVEL_HIGH] = GIO_ASYNC(0x02),
[IRQ_TYPE_LEVEL_LOW] = GIO_ASYNC(0x03),
[IRQ_TYPE_EDGE_BOTH] = GIO_ASYNC(0x04),
};
static int em_gio_irq_set_type(struct irq_data *d, unsigned int type)
{
unsigned char value = em_gio_sense_table[type & IRQ_TYPE_SENSE_MASK];
struct em_gio_priv *p = irq_data_get_irq_chip_data(d);
unsigned int reg, offset, shift;
unsigned long flags;
unsigned long tmp;
if (!value)
return -EINVAL;
offset = irqd_to_hwirq(d);
pr_debug("gio: sense irq = %d, mode = %d\n", offset, value);
/* 8 x 4 bit fields in 4 IDT registers */
reg = GIO_IDT(offset >> 3);
shift = (offset & 0x07) << 4;
spin_lock_irqsave(&p->sense_lock, flags);
/* disable the interrupt in IIA */
tmp = em_gio_read(p, GIO_IIA);
tmp &= ~BIT(offset);
em_gio_write(p, GIO_IIA, tmp);
/* change the sense setting in IDT */
tmp = em_gio_read(p, reg);
tmp &= ~(0xf << shift);
tmp |= value << shift;
em_gio_write(p, reg, tmp);
/* clear pending interrupts */
em_gio_write(p, GIO_IIR, BIT(offset));
/* enable the interrupt in IIA */
tmp = em_gio_read(p, GIO_IIA);
tmp |= BIT(offset);
em_gio_write(p, GIO_IIA, tmp);
spin_unlock_irqrestore(&p->sense_lock, flags);
return 0;
}
static irqreturn_t em_gio_irq_handler(int irq, void *dev_id)
{
struct em_gio_priv *p = dev_id;
unsigned long pending;
unsigned int offset, irqs_handled = 0;
while ((pending = em_gio_read(p, GIO_MST))) {
offset = __ffs(pending);
em_gio_write(p, GIO_IIR, BIT(offset));
generic_handle_irq(irq_find_mapping(p->irq_domain, offset));
irqs_handled++;
}
return irqs_handled ? IRQ_HANDLED : IRQ_NONE;
}
static inline struct em_gio_priv *gpio_to_priv(struct gpio_chip *chip)
{
return container_of(chip, struct em_gio_priv, gpio_chip);
}
static int em_gio_direction_input(struct gpio_chip *chip, unsigned offset)
{
em_gio_write(gpio_to_priv(chip), GIO_E0, BIT(offset));
return 0;
}
static int em_gio_get(struct gpio_chip *chip, unsigned offset)
{
return (int)(em_gio_read(gpio_to_priv(chip), GIO_I) & BIT(offset));
}
static void __em_gio_set(struct gpio_chip *chip, unsigned int reg,
unsigned shift, int value)
{
/* upper 16 bits contains mask and lower 16 actual value */
em_gio_write(gpio_to_priv(chip), reg,
(1 << (shift + 16)) | (value << shift));
}
static void em_gio_set(struct gpio_chip *chip, unsigned offset, int value)
{
/* output is split into two registers */
if (offset < 16)
__em_gio_set(chip, GIO_OL, offset, value);
else
__em_gio_set(chip, GIO_OH, offset - 16, value);
}
static int em_gio_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
/* write GPIO value to output before selecting output mode of pin */
em_gio_set(chip, offset, value);
em_gio_write(gpio_to_priv(chip), GIO_E1, BIT(offset));
return 0;
}
static int em_gio_to_irq(struct gpio_chip *chip, unsigned offset)
{
return irq_find_mapping(gpio_to_priv(chip)->irq_domain, offset);
}
static int em_gio_irq_domain_map(struct irq_domain *h, unsigned int virq,
irq_hw_number_t hw)
{
struct em_gio_priv *p = h->host_data;
pr_debug("gio: map hw irq = %d, virq = %d\n", (int)hw, virq);
irq_set_chip_data(virq, h->host_data);
irq_set_chip_and_handler(virq, &p->irq_chip, handle_level_irq);
set_irq_flags(virq, IRQF_VALID); /* kill me now */
return 0;
}
static struct irq_domain_ops em_gio_irq_domain_ops = {
.map = em_gio_irq_domain_map,
};
static int __devinit em_gio_irq_domain_init(struct em_gio_priv *p)
{
struct platform_device *pdev = p->pdev;
struct gpio_em_config *pdata = pdev->dev.platform_data;
p->irq_base = irq_alloc_descs(pdata->irq_base, 0,
pdata->number_of_pins, numa_node_id());
if (p->irq_base < 0) {
dev_err(&pdev->dev, "cannot get irq_desc\n");
return p->irq_base;
}
pr_debug("gio: hw base = %d, nr = %d, sw base = %d\n",
pdata->gpio_base, pdata->number_of_pins, p->irq_base);
p->irq_domain = irq_domain_add_legacy(pdev->dev.of_node,
pdata->number_of_pins,
p->irq_base, 0,
&em_gio_irq_domain_ops, p);
if (!p->irq_domain) {
irq_free_descs(p->irq_base, pdata->number_of_pins);
return -ENXIO;
}
return 0;
}
static void em_gio_irq_domain_cleanup(struct em_gio_priv *p)
{
struct gpio_em_config *pdata = p->pdev->dev.platform_data;
irq_free_descs(p->irq_base, pdata->number_of_pins);
/* FIXME: irq domain wants to be freed! */
}
static int __devinit em_gio_probe(struct platform_device *pdev)
{
struct gpio_em_config *pdata = pdev->dev.platform_data;
struct em_gio_priv *p;
struct resource *io[2], *irq[2];
struct gpio_chip *gpio_chip;
struct irq_chip *irq_chip;
const char *name = dev_name(&pdev->dev);
int ret;
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (!p) {
dev_err(&pdev->dev, "failed to allocate driver data\n");
ret = -ENOMEM;
goto err0;
}
p->pdev = pdev;
platform_set_drvdata(pdev, p);
spin_lock_init(&p->sense_lock);
io[0] = platform_get_resource(pdev, IORESOURCE_MEM, 0);
io[1] = platform_get_resource(pdev, IORESOURCE_MEM, 1);
irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
if (!io[0] || !io[1] || !irq[0] || !irq[1] || !pdata) {
dev_err(&pdev->dev, "missing IRQ, IOMEM or configuration\n");
ret = -EINVAL;
goto err1;
}
p->base0 = ioremap_nocache(io[0]->start, resource_size(io[0]));
if (!p->base0) {
dev_err(&pdev->dev, "failed to remap low I/O memory\n");
ret = -ENXIO;
goto err1;
}
p->base1 = ioremap_nocache(io[1]->start, resource_size(io[1]));
if (!p->base1) {
dev_err(&pdev->dev, "failed to remap high I/O memory\n");
ret = -ENXIO;
goto err2;
}
gpio_chip = &p->gpio_chip;
gpio_chip->direction_input = em_gio_direction_input;
gpio_chip->get = em_gio_get;
gpio_chip->direction_output = em_gio_direction_output;
gpio_chip->set = em_gio_set;
gpio_chip->to_irq = em_gio_to_irq;
gpio_chip->label = name;
gpio_chip->owner = THIS_MODULE;
gpio_chip->base = pdata->gpio_base;
gpio_chip->ngpio = pdata->number_of_pins;
irq_chip = &p->irq_chip;
irq_chip->name = name;
irq_chip->irq_mask = em_gio_irq_disable;
irq_chip->irq_unmask = em_gio_irq_enable;
irq_chip->irq_enable = em_gio_irq_enable;
irq_chip->irq_disable = em_gio_irq_disable;
irq_chip->irq_set_type = em_gio_irq_set_type;
irq_chip->flags = IRQCHIP_SKIP_SET_WAKE;
ret = em_gio_irq_domain_init(p);
if (ret) {
dev_err(&pdev->dev, "cannot initialize irq domain\n");
goto err3;
}
if (request_irq(irq[0]->start, em_gio_irq_handler, 0, name, p)) {
dev_err(&pdev->dev, "failed to request low IRQ\n");
ret = -ENOENT;
goto err4;
}
if (request_irq(irq[1]->start, em_gio_irq_handler, 0, name, p)) {
dev_err(&pdev->dev, "failed to request high IRQ\n");
ret = -ENOENT;
goto err5;
}
ret = gpiochip_add(gpio_chip);
if (ret) {
dev_err(&pdev->dev, "failed to add GPIO controller\n");
goto err6;
}
return 0;
err6:
free_irq(irq[1]->start, pdev);
err5:
free_irq(irq[0]->start, pdev);
err4:
em_gio_irq_domain_cleanup(p);
err3:
iounmap(p->base1);
err2:
iounmap(p->base0);
err1:
kfree(p);
err0:
return ret;
}
static int __devexit em_gio_remove(struct platform_device *pdev)
{
struct em_gio_priv *p = platform_get_drvdata(pdev);
struct resource *irq[2];
int ret;
ret = gpiochip_remove(&p->gpio_chip);
if (ret)
return ret;
irq[0] = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
irq[1] = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
free_irq(irq[1]->start, pdev);
free_irq(irq[0]->start, pdev);
em_gio_irq_domain_cleanup(p);
iounmap(p->base1);
iounmap(p->base0);
kfree(p);
return 0;
}
static struct platform_driver em_gio_device_driver = {
.probe = em_gio_probe,
.remove = __devexit_p(em_gio_remove),
.driver = {
.name = "em_gio",
}
};
module_platform_driver(em_gio_device_driver);
MODULE_AUTHOR("Magnus Damm");
MODULE_DESCRIPTION("Renesas Emma Mobile GIO Driver");
MODULE_LICENSE("GPL v2");
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