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Release 4.7 drivers/gpio/gpio-sch311x.c

Directory: drivers/gpio
/*
 * 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; }

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static inline void sch311x_sio_exit(int sio_config_port) { outb(SIO_CONFIG_KEY_EXIT, sio_config_port); release_region(sio_config_port, 2); }

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static inline int sch311x_sio_inb(int sio_config_port, int reg) { outb(reg, sio_config_port); return inb(sio_config_port + 1); }

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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); }

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/* * 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; }

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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); }

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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)); }

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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); }

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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); }

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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; }

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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; }

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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; }

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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; }

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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; }

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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; }

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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; }

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static void __exit sch311x_gpio_exit(void) { platform_device_unregister(sch311x_gpio_pdev); platform_driver_unregister(&sch311x_gpio_driver); }

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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");

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Directory: drivers/gpio
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