korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-11-18 17:54:13 +08:00
Code Issues Packages Projects Releases Wiki Activity
d9e742f559
linux/drivers/gpio/gpio-sch311x.c
William Breathitt Gray 1344145785 gpio: sch311x: Use devm_request_region 
By the time request_region is called in the SMSC SCH311x GPIO driver, a
corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.

Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-16 00:19:53 +01:00

430 lines
10 KiB
C
Raw Blame History

/*
* GPIO driver for the SMSC SCH311x Super-I/O chips
*
* Copyright (C) 2013 Bruno Randolf <br1@einfach.org>
*
* SuperIO functions and chip detection:
* (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
*
* 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, or
* (at your option) any later version.
*/
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/gpio.h>
#include <linux/bitops.h>
#include <linux/io.h>
#define DRV_NAME "gpio-sch311x"
#define SCH311X_GPIO_CONF_OUT 0x00
#define SCH311X_GPIO_CONF_IN 0x01
#define SCH311X_GPIO_CONF_INVERT 0x02
#define SCH311X_GPIO_CONF_OPEN_DRAIN 0x80
#define SIO_CONFIG_KEY_ENTER 0x55
#define SIO_CONFIG_KEY_EXIT 0xaa
#define GP1 0x4b
static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e };
static struct platform_device *sch311x_gpio_pdev;
struct sch311x_pdev_data { /* platform device data */
unsigned short runtime_reg; /* runtime register base address */
};
struct sch311x_gpio_block { /* one GPIO block runtime data */
struct gpio_chip chip;
unsigned short data_reg; /* from definition below */
unsigned short *config_regs; /* pointer to definition below */
unsigned short runtime_reg; /* runtime register */
spinlock_t lock; /* lock for this GPIO block */
};
struct sch311x_gpio_priv { /* driver private data */
struct sch311x_gpio_block blocks[6];
};
struct sch311x_gpio_block_def { /* register address definitions */
unsigned short data_reg;
unsigned short config_regs[8];
unsigned short base;
};
/* Note: some GPIOs are not available, these are marked with 0x00 */
static struct sch311x_gpio_block_def sch311x_gpio_blocks[] = {
{
.data_reg = 0x4b, /* GP1 */
.config_regs = {0x23, 0x24, 0x25, 0x26, 0x27, 0x29, 0x2a, 0x2b},
.base = 10,
},
{
.data_reg = 0x4c, /* GP2 */
.config_regs = {0x00, 0x2c, 0x2d, 0x00, 0x00, 0x00, 0x00, 0x32},
.base = 20,
},
{
.data_reg = 0x4d, /* GP3 */
.config_regs = {0x33, 0x34, 0x35, 0x36, 0x37, 0x00, 0x39, 0x3a},
.base = 30,
},
{
.data_reg = 0x4e, /* GP4 */
.config_regs = {0x3b, 0x00, 0x3d, 0x00, 0x6e, 0x6f, 0x72, 0x73},
.base = 40,
},
{
.data_reg = 0x4f, /* GP5 */
.config_regs = {0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46},
.base = 50,
},
{
.data_reg = 0x50, /* GP6 */
.config_regs = {0x47, 0x48, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59},
.base = 60,
},
};
/*
* Super-IO functions
*/
static inline int sch311x_sio_enter(int sio_config_port)
{
/* Don't step on other drivers' I/O space by accident. */
if (!request_muxed_region(sio_config_port, 2, DRV_NAME)) {
pr_err(DRV_NAME "I/O address 0x%04x already in use\n",
sio_config_port);
return -EBUSY;
}
outb(SIO_CONFIG_KEY_ENTER, sio_config_port);
return 0;
}
static inline void sch311x_sio_exit(int sio_config_port)
{
outb(SIO_CONFIG_KEY_EXIT, sio_config_port);
release_region(sio_config_port, 2);
}
static inline int sch311x_sio_inb(int sio_config_port, int reg)
{
outb(reg, sio_config_port);
return inb(sio_config_port + 1);
}
static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
{
outb(reg, sio_config_port);
outb(val, sio_config_port + 1);
}
/*
* GPIO functions
*/
static int sch311x_gpio_request(struct gpio_chip *chip, unsigned offset)
{
struct sch311x_gpio_block *block = gpiochip_get_data(chip);
if (block->config_regs[offset] == 0) /* GPIO is not available */
return -ENODEV;
if (!request_region(block->runtime_reg + block->config_regs[offset],
1, DRV_NAME)) {
dev_err(chip->parent, "Failed to request region 0x%04x.\n",
block->runtime_reg + block->config_regs[offset]);
return -EBUSY;
}
return 0;
}
static void sch311x_gpio_free(struct gpio_chip *chip, unsigned offset)
{
struct sch311x_gpio_block *block = gpiochip_get_data(chip);
if (block->config_regs[offset] == 0) /* GPIO is not available */
return;
release_region(block->runtime_reg + block->config_regs[offset], 1);
}
static int sch311x_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct sch311x_gpio_block *block = gpiochip_get_data(chip);
unsigned char data;
spin_lock(&block->lock);
data = inb(block->runtime_reg + block->data_reg);
spin_unlock(&block->lock);
return !!(data & BIT(offset));
}
static void __sch311x_gpio_set(struct sch311x_gpio_block *block,
unsigned offset, int value)
{
unsigned char data = inb(block->runtime_reg + block->data_reg);
if (value)
data |= BIT(offset);
else
data &= ~BIT(offset);
outb(data, block->runtime_reg + block->data_reg);
}
static void sch311x_gpio_set(struct gpio_chip *chip, unsigned offset,
int value)
{
struct sch311x_gpio_block *block = gpiochip_get_data(chip);
spin_lock(&block->lock);
__sch311x_gpio_set(block, offset, value);
spin_unlock(&block->lock);
}
static int sch311x_gpio_direction_in(struct gpio_chip *chip, unsigned offset)
{
struct sch311x_gpio_block *block = gpiochip_get_data(chip);
spin_lock(&block->lock);
outb(SCH311X_GPIO_CONF_IN, block->runtime_reg +
block->config_regs[offset]);
spin_unlock(&block->lock);
return 0;
}
static int sch311x_gpio_direction_out(struct gpio_chip *chip, unsigned offset,
int value)
{
struct sch311x_gpio_block *block = gpiochip_get_data(chip);
spin_lock(&block->lock);
outb(SCH311X_GPIO_CONF_OUT, block->runtime_reg +
block->config_regs[offset]);
__sch311x_gpio_set(block, offset, value);
spin_unlock(&block->lock);
return 0;
}
static int sch311x_gpio_probe(struct platform_device *pdev)
{
struct sch311x_pdev_data *pdata = dev_get_platdata(&pdev->dev);
struct sch311x_gpio_priv *priv;
struct sch311x_gpio_block *block;
int err, i;
/* we can register all GPIO data registers at once */
if (!devm_request_region(&pdev->dev, pdata->runtime_reg + GP1, 6,
DRV_NAME)) {
dev_err(&pdev->dev, "Failed to request region 0x%04x-0x%04x.\n",
pdata->runtime_reg + GP1, pdata->runtime_reg + GP1 + 5);
return -EBUSY;
}
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
platform_set_drvdata(pdev, priv);
for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
block = &priv->blocks[i];
spin_lock_init(&block->lock);
block->chip.label = DRV_NAME;
block->chip.owner = THIS_MODULE;
block->chip.request = sch311x_gpio_request;
block->chip.free = sch311x_gpio_free;
block->chip.direction_input = sch311x_gpio_direction_in;
block->chip.direction_output = sch311x_gpio_direction_out;
block->chip.get = sch311x_gpio_get;
block->chip.set = sch311x_gpio_set;
block->chip.ngpio = 8;
block->chip.parent = &pdev->dev;
block->chip.base = sch311x_gpio_blocks[i].base;
block->config_regs = sch311x_gpio_blocks[i].config_regs;
block->data_reg = sch311x_gpio_blocks[i].data_reg;
block->runtime_reg = pdata->runtime_reg;
err = gpiochip_add_data(&block->chip, block);
if (err < 0) {
dev_err(&pdev->dev,
"Could not register gpiochip, %d\n", err);
goto exit_err;
}
dev_info(&pdev->dev,
"SMSC SCH311x GPIO block %d registered.\n", i);
}
return 0;
exit_err:
/* release already registered chips */
for (--i; i >= 0; i--)
gpiochip_remove(&priv->blocks[i].chip);
return err;
}
static int sch311x_gpio_remove(struct platform_device *pdev)
{
struct sch311x_gpio_priv *priv = platform_get_drvdata(pdev);
int i;
for (i = 0; i < ARRAY_SIZE(priv->blocks); i++) {
gpiochip_remove(&priv->blocks[i].chip);
dev_info(&pdev->dev,
"SMSC SCH311x GPIO block %d unregistered.\n", i);
}
return 0;
}
static struct platform_driver sch311x_gpio_driver = {
.driver.name = DRV_NAME,
.driver.owner = THIS_MODULE,
.probe = sch311x_gpio_probe,
.remove = sch311x_gpio_remove,
};
/*
* Init & exit routines
*/
static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
{
int err = 0, reg;
unsigned short base_addr;
unsigned char dev_id;
err = sch311x_sio_enter(sio_config_port);
if (err)
return err;
/* Check device ID. */
reg = sch311x_sio_inb(sio_config_port, 0x20);
switch (reg) {
case 0x7c: /* SCH3112 */
dev_id = 2;
break;
case 0x7d: /* SCH3114 */
dev_id = 4;
break;
case 0x7f: /* SCH3116 */
dev_id = 6;
break;
default:
err = -ENODEV;
goto exit;
}
/* Select logical device A (runtime registers) */
sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
/* Check if Logical Device Register is currently active */
if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
pr_info("Seems that LDN 0x0a is not active...\n");
/* Get the base address of the runtime registers */
base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
sch311x_sio_inb(sio_config_port, 0x61);
if (!base_addr) {
pr_err("Base address not set\n");
err = -ENODEV;
goto exit;
}
*addr = base_addr;
pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
exit:
sch311x_sio_exit(sio_config_port);
return err;
}
static int __init sch311x_gpio_pdev_add(const unsigned short addr)
{
struct sch311x_pdev_data pdata;
int err;
pdata.runtime_reg = addr;
sch311x_gpio_pdev = platform_device_alloc(DRV_NAME, -1);
if (!sch311x_gpio_pdev)
return -ENOMEM;
err = platform_device_add_data(sch311x_gpio_pdev,
&pdata, sizeof(pdata));
if (err) {
pr_err(DRV_NAME "Platform data allocation failed\n");
goto err;
}
err = platform_device_add(sch311x_gpio_pdev);
if (err) {
pr_err(DRV_NAME "Device addition failed\n");
goto err;
}
return 0;
err:
platform_device_put(sch311x_gpio_pdev);
return err;
}
static int __init sch311x_gpio_init(void)
{
int err, i;
unsigned short addr = 0;
for (i = 0; i < ARRAY_SIZE(sch311x_ioports); i++)
if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
break;
if (!addr)
return -ENODEV;
err = platform_driver_register(&sch311x_gpio_driver);
if (err)
return err;
err = sch311x_gpio_pdev_add(addr);
if (err)
goto unreg_platform_driver;
return 0;
unreg_platform_driver:
platform_driver_unregister(&sch311x_gpio_driver);
return err;
}
static void __exit sch311x_gpio_exit(void)
{
platform_device_unregister(sch311x_gpio_pdev);
platform_driver_unregister(&sch311x_gpio_driver);
}
module_init(sch311x_gpio_init);
module_exit(sch311x_gpio_exit);
MODULE_AUTHOR("Bruno Randolf <br1@einfach.org>");
MODULE_DESCRIPTION("SMSC SCH311x GPIO Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:gpio-sch311x");
Reference in New Issue View Git Blame Copy Permalink