path: root/drivers/i2c/busses/i2c-s3c2410.c

/* linux/drivers/i2c/busses/i2c-s3c2410.c
 *
 * Copyright (C) 2004,2005,2009 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * S3C2410 I2C Controller
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <linux/kernel.h>
#include <linux/module.h>

#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/clk.h>
#include <linux/cpufreq.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/of_i2c.h>
#include <linux/of_gpio.h>
#include <linux/pinctrl/consumer.h>

#include <asm/irq.h>

#include <linux/platform_data/i2c-s3c2410.h>

/* see s3c2410x user guide, v1.1, section 9 (p447) for more info */

#define S3C2410_IICCON			0x00
#define S3C2410_IICSTAT			0x04
#define S3C2410_IICADD			0x08
#define S3C2410_IICDS			0x0C
#define S3C2440_IICLC			0x10

#define S3C2410_IICCON_ACKEN		(1 << 7)
#define S3C2410_IICCON_TXDIV_16		(0 << 6)
#define S3C2410_IICCON_TXDIV_512	(1 << 6)
#define S3C2410_IICCON_IRQEN		(1 << 5)
#define S3C2410_IICCON_IRQPEND		(1 << 4)
#define S3C2410_IICCON_SCALE(x)		((x) & 0xf)
#define S3C2410_IICCON_SCALEMASK	(0xf)

#define S3C2410_IICSTAT_MASTER_RX	(2 << 6)
#define S3C2410_IICSTAT_MASTER_TX	(3 << 6)
#define S3C2410_IICSTAT_SLAVE_RX	(0 << 6)
#define S3C2410_IICSTAT_SLAVE_TX	(1 << 6)
#define S3C2410_IICSTAT_MODEMASK	(3 << 6)

#define S3C2410_IICSTAT_START		(1 << 5)
#define S3C2410_IICSTAT_BUSBUSY		(1 << 5)
#define S3C2410_IICSTAT_TXRXEN		(1 << 4)
#define S3C2410_IICSTAT_ARBITR		(1 << 3)
#define S3C2410_IICSTAT_ASSLAVE		(1 << 2)
#define S3C2410_IICSTAT_ADDR0		(1 << 1)
#define S3C2410_IICSTAT_LASTBIT		(1 << 0)

#define S3C2410_IICLC_SDA_DELAY0	(0 << 0)
#define S3C2410_IICLC_SDA_DELAY5	(1 << 0)
#define S3C2410_IICLC_SDA_DELAY10	(2 << 0)
#define S3C2410_IICLC_SDA_DELAY15	(3 << 0)
#define S3C2410_IICLC_SDA_DELAY_MASK	(3 << 0)

#define S3C2410_IICLC_FILTER_ON		(1 << 2)

/* Treat S3C2410 as baseline hardware, anything else is supported via quirks */
#define QUIRK_S3C2440		(1 << 0)
#define QUIRK_HDMIPHY		(1 << 1)
#define QUIRK_NO_GPIO		(1 << 2)

/* Max time to wait for bus to become idle after a xfer (in us) */
#define S3C2410_IDLE_TIMEOUT	5000

/* i2c controller state */
enum s3c24xx_i2c_state {
	STATE_IDLE,
	STATE_START,
	STATE_READ,
	STATE_WRITE,
	STATE_STOP
};

struct s3c24xx_i2c {
	wait_queue_head_t	wait;
	unsigned int            quirks;
	unsigned int		suspended:1;

	struct i2c_msg		*msg;
	unsigned int		msg_num;
	unsigned int		msg_idx;
	unsigned int		msg_ptr;

	unsigned int		tx_setup;
	unsigned int		irq;

	enum s3c24xx_i2c_state	state;
	unsigned long		clkrate;

	void __iomem		*regs;
	struct clk		*clk;
	struct device		*dev;
	struct i2c_adapter	adap;

	struct s3c2410_platform_i2c	*pdata;
	int			gpios[2];
	struct pinctrl          *pctrl;
#ifdef CONFIG_CPU_FREQ
	struct notifier_block	freq_transition;
#endif
};

static struct platform_device_id s3c24xx_driver_ids[] = {
	{
		.name		= "s3c2410-i2c",
		.driver_data	= 0,
	}, {
		.name		= "s3c2440-i2c",
		.driver_data	= QUIRK_S3C2440,
	}, {
		.name		= "s3c2440-hdmiphy-i2c",
		.driver_data	= QUIRK_S3C2440 | QUIRK_HDMIPHY | QUIRK_NO_GPIO,
	}, { },
};
MODULE_DEVICE_TABLE(platform, s3c24xx_driver_ids);

#ifdef CONFIG_OF
static const