kernel-fxtec-pro1x/arch/arm/common/scoop.c
Linus Walleij 86d5e657d2 ARM: scoop: Be sure to clamp return value
As we want gpio_chip .get() calls to be able to return negative
error codes and propagate to drivers, we need to go over all
drivers and make sure their return values are clamped to [0,1].
We do this by using the ret = !!(val) design pattern.

Cc: arm@kernel.org
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Olof Johansson <olof@lixom.net>
2015-12-22 14:57:21 -08:00

275 lines
6.6 KiB
C

/*
* Support code for the SCOOP interface found on various Sharp PDAs
*
* Copyright (c) 2004 Richard Purdie
*
* Based on code written by Sharp/Lineo for 2.4 kernels
*
* 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.
*
*/
#include <linux/device.h>
#include <linux/gpio.h>
#include <linux/string.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/export.h>
#include <linux/io.h>
#include <asm/hardware/scoop.h>
/* PCMCIA to Scoop linkage
There is no easy way to link multiple scoop devices into one
single entity for the pxa2xx_pcmcia device so this structure
is used which is setup by the platform code.
This file is never modular so this symbol is always
accessile to the board support files.
*/
struct scoop_pcmcia_config *platform_scoop_config;
EXPORT_SYMBOL(platform_scoop_config);
struct scoop_dev {
void __iomem *base;
struct gpio_chip gpio;
spinlock_t scoop_lock;
unsigned short suspend_clr;
unsigned short suspend_set;
u32 scoop_gpwr;
};
void reset_scoop(struct device *dev)
{
struct scoop_dev *sdev = dev_get_drvdata(dev);
iowrite16(0x0100, sdev->base + SCOOP_MCR); /* 00 */
iowrite16(0x0000, sdev->base + SCOOP_CDR); /* 04 */
iowrite16(0x0000, sdev->base + SCOOP_CCR); /* 10 */
iowrite16(0x0000, sdev->base + SCOOP_IMR); /* 18 */
iowrite16(0x00FF, sdev->base + SCOOP_IRM); /* 14 */
iowrite16(0x0000, sdev->base + SCOOP_ISR); /* 1C */
iowrite16(0x0000, sdev->base + SCOOP_IRM);
}
static void __scoop_gpio_set(struct scoop_dev *sdev,
unsigned offset, int value)
{
unsigned short gpwr;
gpwr = ioread16(sdev->base + SCOOP_GPWR);
if (value)
gpwr |= 1 << (offset + 1);
else
gpwr &= ~(1 << (offset + 1));
iowrite16(gpwr, sdev->base + SCOOP_GPWR);
}
static void scoop_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
unsigned long flags;
spin_lock_irqsave(&sdev->scoop_lock, flags);
__scoop_gpio_set(sdev, offset, value);
spin_unlock_irqrestore(&sdev->scoop_lock, flags);
}
static int scoop_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
/* XXX: I'm unsure, but it seems so */
return !!(ioread16(sdev->base + SCOOP_GPRR) & (1 << (offset + 1)));
}
static int scoop_gpio_direction_input(struct gpio_chip *chip,
unsigned offset)
{
struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
unsigned long flags;
unsigned short gpcr;
spin_lock_irqsave(&sdev->scoop_lock, flags);
gpcr = ioread16(sdev->base + SCOOP_GPCR);
gpcr &= ~(1 << (offset + 1));
iowrite16(gpcr, sdev->base + SCOOP_GPCR);
spin_unlock_irqrestore(&sdev->scoop_lock, flags);
return 0;
}
static int scoop_gpio_direction_output(struct gpio_chip *chip,
unsigned offset, int value)
{
struct scoop_dev *sdev = container_of(chip, struct scoop_dev, gpio);
unsigned long flags;
unsigned short gpcr;
spin_lock_irqsave(&sdev->scoop_lock, flags);
__scoop_gpio_set(sdev, offset, value);
gpcr = ioread16(sdev->base + SCOOP_GPCR);
gpcr |= 1 << (offset + 1);
iowrite16(gpcr, sdev->base + SCOOP_GPCR);
spin_unlock_irqrestore(&sdev->scoop_lock, flags);
return 0;
}
unsigned short read_scoop_reg(struct device *dev, unsigned short reg)
{
struct scoop_dev *sdev = dev_get_drvdata(dev);
return ioread16(sdev->base + reg);
}
void write_scoop_reg(struct device *dev, unsigned short reg, unsigned short data)
{
struct scoop_dev *sdev = dev_get_drvdata(dev);
iowrite16(data, sdev->base + reg);
}
EXPORT_SYMBOL(reset_scoop);
EXPORT_SYMBOL(read_scoop_reg);
EXPORT_SYMBOL(write_scoop_reg);
#ifdef CONFIG_PM
static void check_scoop_reg(struct scoop_dev *sdev)
{
unsigned short mcr;
mcr = ioread16(sdev->base + SCOOP_MCR);
if ((mcr & 0x100) == 0)
iowrite16(0x0101, sdev->base + SCOOP_MCR);
}
static int scoop_suspend(struct platform_device *dev, pm_message_t state)
{
struct scoop_dev *sdev = platform_get_drvdata(dev);
check_scoop_reg(sdev);
sdev->scoop_gpwr = ioread16(sdev->base + SCOOP_GPWR);
iowrite16((sdev->scoop_gpwr & ~sdev->suspend_clr) | sdev->suspend_set, sdev->base + SCOOP_GPWR);
return 0;
}
static int scoop_resume(struct platform_device *dev)
{
struct scoop_dev *sdev = platform_get_drvdata(dev);
check_scoop_reg(sdev);
iowrite16(sdev->scoop_gpwr, sdev->base + SCOOP_GPWR);
return 0;
}
#else
#define scoop_suspend NULL
#define scoop_resume NULL
#endif
static int scoop_probe(struct platform_device *pdev)
{
struct scoop_dev *devptr;
struct scoop_config *inf;
struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
int ret;
if (!mem)
return -EINVAL;
devptr = kzalloc(sizeof(struct scoop_dev), GFP_KERNEL);
if (!devptr)
return -ENOMEM;
spin_lock_init(&devptr->scoop_lock);
inf = pdev->dev.platform_data;
devptr->base = ioremap(mem->start, resource_size(mem));
if (!devptr->base) {
ret = -ENOMEM;
goto err_ioremap;
}
platform_set_drvdata(pdev, devptr);
printk("Sharp Scoop Device found at 0x%08x -> 0x%8p\n",(unsigned int)mem->start, devptr->base);
iowrite16(0x0140, devptr->base + SCOOP_MCR);
reset_scoop(&pdev->dev);
iowrite16(0x0000, devptr->base + SCOOP_CPR);
iowrite16(inf->io_dir & 0xffff, devptr->base + SCOOP_GPCR);
iowrite16(inf->io_out & 0xffff, devptr->base + SCOOP_GPWR);
devptr->suspend_clr = inf->suspend_clr;
devptr->suspend_set = inf->suspend_set;
devptr->gpio.base = -1;
if (inf->gpio_base != 0) {
devptr->gpio.label = dev_name(&pdev->dev);
devptr->gpio.base = inf->gpio_base;
devptr->gpio.ngpio = 12; /* PA11 = 0, PA12 = 1, etc. up to PA22 = 11 */
devptr->gpio.set = scoop_gpio_set;
devptr->gpio.get = scoop_gpio_get;
devptr->gpio.direction_input = scoop_gpio_direction_input;
devptr->gpio.direction_output = scoop_gpio_direction_output;
ret = gpiochip_add(&devptr->gpio);
if (ret)
goto err_gpio;
}
return 0;
err_gpio:
platform_set_drvdata(pdev, NULL);
err_ioremap:
iounmap(devptr->base);
kfree(devptr);
return ret;
}
static int scoop_remove(struct platform_device *pdev)
{
struct scoop_dev *sdev = platform_get_drvdata(pdev);
if (!sdev)
return -EINVAL;
if (sdev->gpio.base != -1)
gpiochip_remove(&sdev->gpio);
platform_set_drvdata(pdev, NULL);
iounmap(sdev->base);
kfree(sdev);
return 0;
}
static struct platform_driver scoop_driver = {
.probe = scoop_probe,
.remove = scoop_remove,
.suspend = scoop_suspend,
.resume = scoop_resume,
.driver = {
.name = "sharp-scoop",
},
};
static int __init scoop_init(void)
{
return platform_driver_register(&scoop_driver);
}
subsys_initcall(scoop_init);