[linux.git] / drivers / gpio / gpio-rdc321x.c

/*
 * RDC321x GPIO driver
 *
 * Copyright (C) 2008, Volker Weiss <[email protected]>
 * Copyright (C) 2007-2010 Florian Fainelli <[email protected]>
 *
 * 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.
 *
 * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/spinlock.h>
#include <linux/platform_device.h>
#include <linux/pci.h>
#include <linux/gpio.h>
#include <linux/mfd/rdc321x.h>
#include <linux/slab.h>

struct rdc321x_gpio {
	spinlock_t		lock;
	struct pci_dev		*sb_pdev;
	u32			data_reg[2];
	int			reg1_ctrl_base;
	int			reg1_data_base;
	int			reg2_ctrl_base;
	int			reg2_data_base;
	struct gpio_chip	chip;
};

/* read GPIO pin */
static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
{
	struct rdc321x_gpio *gpch;
	u32 value = 0;
	int reg;

	gpch = gpiochip_get_data(chip);
	reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;

	spin_lock(&gpch->lock);
	pci_write_config_dword(gpch->sb_pdev, reg,
					gpch->data_reg[gpio < 32 ? 0 : 1]);
	pci_read_config_dword(gpch->sb_pdev, reg, &value);
	spin_unlock(&gpch->lock);

	return (1 << (gpio & 0x1f)) & value ? 1 : 0;
}

static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
				unsigned gpio, int value)
{
	struct rdc321x_gpio *gpch;
	int reg = (gpio < 32) ? 0 : 1;

	gpch = gpiochip_get_data(chip);

	if (value)
		gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
	else
		gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));

	pci_write_config_dword(gpch->sb_pdev,
			reg ? gpch->reg2_data_base : gpch->reg1_data_base,
			gpch->data_reg[reg]);
}

/* set GPIO pin to value */
static void rdc_gpio_set_value(struct gpio_chip *chip,
				unsigned gpio, int value)
{
	struct rdc321x_gpio *gpch;

	gpch = gpiochip_get_data(chip);
	spin_lock(&gpch->lock);
	rdc_gpio_set_value_impl(chip, gpio, value);
	spin_unlock(&gpch->lock);
}

static int rdc_gpio_config(struct gpio_chip *chip,
				unsigned gpio, int value)
{
	struct rdc321x_gpio *gpch;
	int err;
	u32 reg;

	gpch = gpiochip_get_data(chip);

	spin_lock(&gpch->lock);
	err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
			gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
	if (err)
		goto unlock;

	reg |= 1 << (gpio & 0x1f);

	err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
			gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
	if (err)
		goto unlock;

	rdc_gpio_set_value_impl(chip, gpio, value);

unlock:
	spin_unlock(&gpch->lock);

	return err;
}

/* configure GPIO pin as input */
static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
{
	return rdc_gpio_config(chip, gpio, 1);
}

/*
 * Cache the initial value of both GPIO data registers
 */
static int rdc321x_gpio_probe(struct platform_device *pdev)
{
	int err;
	struct resource *r;
	struct rdc321x_gpio *rdc321x_gpio_dev;
	struct rdc321x_gpio_pdata *pdata;

	pdata = dev_get_platdata(&pdev->dev);
	if (!pdata) {
		dev_err(&pdev->dev, "no platform data supplied\n");
		return -ENODEV;
	}

	rdc321x_gpio_dev = devm_kzalloc(&pdev->dev, sizeof(struct rdc321x_gpio),
					GFP_KERNEL);
	if (!rdc321x_gpio_dev)
		return -ENOMEM;

	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
	if (!r) {
		dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
		return -ENODEV;
	}

	spin_lock_init(&rdc321x_gpio_dev->lock);
	rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
	rdc321x_gpio_dev->reg1_ctrl_base = r->start;
	rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;

	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
	if (!r) {
		dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
		return -ENODEV;
	}

	rdc321x_gpio_dev->reg2_ctrl_base = r->start;
	rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;

	rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
	rdc321x_gpio_dev->chip.owner = THIS_MODULE;
	rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
	rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
	rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
	rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
	rdc321x_gpio_dev->chip.base = 0;
	rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;

	platform_set_drvdata(pdev, rdc321x_gpio_dev);

	/* This might not be, what others (BIOS, bootloader, etc.)
	   wrote to these registers before, but it's a good guess. Still
	   better than just using 0xffffffff. */
	err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
					rdc321x_gpio_dev->reg1_data_base,
					&rdc321x_gpio_dev->data_reg[0]);
	if (err)
		return err;

	err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
					rdc321x_gpio_dev->reg2_data_base,
					&rdc321x_gpio_dev->data_reg[1]);
	if (err)
		return err;

	dev_info(&pdev->dev, "registering %d GPIOs\n",
					rdc321x_gpio_dev->chip.ngpio);
	return devm_gpiochip_add_data(&pdev->dev, &rdc321x_gpio_dev->chip,
				      rdc321x_gpio_dev);
}

static struct platform_driver rdc321x_gpio_driver = {
	.driver.name	= "rdc321x-gpio",
	.driver.owner	= THIS_MODULE,
	.probe		= rdc321x_gpio_probe,
};

module_platform_driver(rdc321x_gpio_driver);

MODULE_AUTHOR("Florian Fainelli <[email protected]>");
MODULE_DESCRIPTION("RDC321x GPIO driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:rdc321x-gpio");
Commit	Line	Data
9956d02d FF	1	/*
	2	* RDC321x GPIO driver
	3	*
	4	* Copyright (C) 2008, Volker Weiss <[email protected]>
	5	* Copyright (C) 2007-2010 Florian Fainelli <[email protected]>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	20	*
	21	*/
	22	#include <linux/module.h>
	23	#include <linux/kernel.h>
	24	#include <linux/init.h>
	25	#include <linux/spinlock.h>
	26	#include <linux/platform_device.h>
	27	#include <linux/pci.h>
	28	#include <linux/gpio.h>
	29	#include <linux/mfd/rdc321x.h>
374b72ec	30	#include <linux/slab.h>
9956d02d FF	31
	32	struct rdc321x_gpio {
	33	spinlock_t lock;
	34	struct pci_dev *sb_pdev;
	35	u32 data_reg[2];
	36	int reg1_ctrl_base;
	37	int reg1_data_base;
	38	int reg2_ctrl_base;
	39	int reg2_data_base;
	40	struct gpio_chip chip;
	41	};
	42
	43	/* read GPIO pin */
	44	static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
	45	{
	46	struct rdc321x_gpio *gpch;
	47	u32 value = 0;
	48	int reg;
	49
78132252	50	gpch = gpiochip_get_data(chip);
9956d02d FF	51	reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
	52
	53	spin_lock(&gpch->lock);
	54	pci_write_config_dword(gpch->sb_pdev, reg,
	55	gpch->data_reg[gpio < 32 ? 0 : 1]);
	56	pci_read_config_dword(gpch->sb_pdev, reg, &value);
	57	spin_unlock(&gpch->lock);
	58
	59	return (1 << (gpio & 0x1f)) & value ? 1 : 0;
	60	}
	61
	62	static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
	63	unsigned gpio, int value)
	64	{
	65	struct rdc321x_gpio *gpch;
	66	int reg = (gpio < 32) ? 0 : 1;
	67
78132252	68	gpch = gpiochip_get_data(chip);
9956d02d FF	69
	70	if (value)
	71	gpch->data_reg[reg] \|= 1 << (gpio & 0x1f);
	72	else
	73	gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
	74
	75	pci_write_config_dword(gpch->sb_pdev,
75907a11	76	reg ? gpch->reg2_data_base : gpch->reg1_data_base,
9956d02d FF	77	gpch->data_reg[reg]);
	78	}
	79
	80	/* set GPIO pin to value */
	81	static void rdc_gpio_set_value(struct gpio_chip *chip,
	82	unsigned gpio, int value)
	83	{
	84	struct rdc321x_gpio *gpch;
	85
78132252	86	gpch = gpiochip_get_data(chip);
9956d02d FF	87	spin_lock(&gpch->lock);
	88	rdc_gpio_set_value_impl(chip, gpio, value);
	89	spin_unlock(&gpch->lock);
	90	}
	91
	92	static int rdc_gpio_config(struct gpio_chip *chip,
	93	unsigned gpio, int value)
	94	{
	95	struct rdc321x_gpio *gpch;
	96	int err;
	97	u32 reg;
	98
78132252	99	gpch = gpiochip_get_data(chip);
9956d02d FF	100
	101	spin_lock(&gpch->lock);
	102	err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
	103	gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
	104	if (err)
	105	goto unlock;
	106
	107	reg \|= 1 << (gpio & 0x1f);
	108
	109	err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
	110	gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
	111	if (err)
	112	goto unlock;
	113
	114	rdc_gpio_set_value_impl(chip, gpio, value);
	115
	116	unlock:
	117	spin_unlock(&gpch->lock);
	118
	119	return err;
	120	}
	121
	122	/* configure GPIO pin as input */
	123	static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
	124	{
	125	return rdc_gpio_config(chip, gpio, 1);
	126	}
	127
	128	/*
	129	* Cache the initial value of both GPIO data registers
	130	*/
3836309d	131	static int rdc321x_gpio_probe(struct platform_device *pdev)
9956d02d FF	132	{
	133	int err;
	134	struct resource *r;
	135	struct rdc321x_gpio *rdc321x_gpio_dev;
	136	struct rdc321x_gpio_pdata *pdata;
	137
e56aee18	138	pdata = dev_get_platdata(&pdev->dev);
9956d02d FF	139	if (!pdata) {
	140	dev_err(&pdev->dev, "no platform data supplied\n");
	141	return -ENODEV;
	142	}
	143
95ad6b9d AL	144	rdc321x_gpio_dev = devm_kzalloc(&pdev->dev, sizeof(struct rdc321x_gpio),
95ad6b9d AL	145	GFP_KERNEL);
84e27f97	146	if (!rdc321x_gpio_dev)
9956d02d	147	return -ENOMEM;
9956d02d	148
8deca39e	149	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
9956d02d FF	150	if (!r) {
9956d02d FF	151	dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
95ad6b9d	152	return -ENODEV;
9956d02d FF	153	}
	154
	155	spin_lock_init(&rdc321x_gpio_dev->lock);
	156	rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
	157	rdc321x_gpio_dev->reg1_ctrl_base = r->start;
	158	rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
	159
8deca39e	160	r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
9956d02d FF	161	if (!r) {
9956d02d FF	162	dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
95ad6b9d	163	return -ENODEV;
9956d02d FF	164	}
	165
	166	rdc321x_gpio_dev->reg2_ctrl_base = r->start;
	167	rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
	168
	169	rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
1146f882	170	rdc321x_gpio_dev->chip.owner = THIS_MODULE;
9956d02d FF	171	rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
	172	rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
	173	rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
	174	rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
	175	rdc321x_gpio_dev->chip.base = 0;
	176	rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;
	177
	178	platform_set_drvdata(pdev, rdc321x_gpio_dev);
	179
	180	/* This might not be, what others (BIOS, bootloader, etc.)
	181	wrote to these registers before, but it's a good guess. Still
	182	better than just using 0xffffffff. */
	183	err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
	184	rdc321x_gpio_dev->reg1_data_base,
	185	&rdc321x_gpio_dev->data_reg[0]);
	186	if (err)
95ad6b9d	187	return err;
9956d02d FF	188
	189	err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
	190	rdc321x_gpio_dev->reg2_data_base,
	191	&rdc321x_gpio_dev->data_reg[1]);
	192	if (err)
95ad6b9d	193	return err;
9956d02d FF	194
	195	dev_info(&pdev->dev, "registering %d GPIOs\n",
	196	rdc321x_gpio_dev->chip.ngpio);
cfae2c90 LD	197	return devm_gpiochip_add_data(&pdev->dev, &rdc321x_gpio_dev->chip,
cfae2c90 LD	198	rdc321x_gpio_dev);
9956d02d FF	199	}
	200
	201	static struct platform_driver rdc321x_gpio_driver = {
	202	.driver.name = "rdc321x-gpio",
	203	.driver.owner = THIS_MODULE,
	204	.probe = rdc321x_gpio_probe,
9956d02d FF	205	};
9956d02d FF	206
6f61415e	207	module_platform_driver(rdc321x_gpio_driver);
9956d02d FF	208
	209	MODULE_AUTHOR("Florian Fainelli <[email protected]>");
	210	MODULE_DESCRIPTION("RDC321x GPIO driver");
	211	MODULE_LICENSE("GPL");
	212	MODULE_ALIAS("platform:rdc321x-gpio");