path: root/drivers/i2c/busses/i2c-i801.c

/*
    Copyright (c) 1998 - 2002  Frodo Looijaard <frodol@dds.nl>,
    Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker
    <mdsxyz123@yahoo.com>
    Copyright (C) 2007 - 2012  Jean Delvare <khali@linux-fr.org>
    Copyright (C) 2010         Intel Corporation,
                               David Woodhouse <dwmw2@infradead.org>

    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.
*/

/*
  Supports the following Intel I/O Controller Hubs (ICH):

                                  I/O                     Block   I2C
                                  region  SMBus   Block   proc.   block
  Chip name             PCI ID    size    PEC     buffer  call    read
  ----------------------------------------------------------------------
  82801AA  (ICH)        0x2413     16      no      no      no      no
  82801AB  (ICH0)       0x2423     16      no      no      no      no
  82801BA  (ICH2)       0x2443     16      no      no      no      no
  82801CA  (ICH3)       0x2483     32     soft     no      no      no
  82801DB  (ICH4)       0x24c3     32     hard     yes     no      no
  82801E   (ICH5)       0x24d3     32     hard     yes     yes     yes
  6300ESB               0x25a4     32     hard     yes     yes     yes
  82801F   (ICH6)       0x266a     32     hard     yes     yes     yes
  6310ESB/6320ESB       0x269b     32     hard     yes     yes     yes
  82801G   (ICH7)       0x27da     32     hard     yes     yes     yes
  82801H   (ICH8)       0x283e     32     hard     yes     yes     yes
  82801I   (ICH9)       0x2930     32     hard     yes     yes     yes
  EP80579 (Tolapai)     0x5032     32     hard     yes     yes     yes
  ICH10                 0x3a30     32     hard     yes     yes     yes
  ICH10                 0x3a60     32     hard     yes     yes     yes
  5/3400 Series (PCH)   0x3b30     32     hard     yes     yes     yes
  6 Series (PCH)        0x1c22     32     hard     yes     yes     yes
  Patsburg (PCH)        0x1d22     32     hard     yes     yes     yes
  Patsburg (PCH) IDF    0x1d70     32     hard     yes     yes     yes
  Patsburg (PCH) IDF    0x1d71     32     hard     yes     yes     yes
  Patsburg (PCH) IDF    0x1d72     32     hard     yes     yes     yes
  DH89xxCC (PCH)        0x2330     32     hard     yes     yes     yes
  Panther Point (PCH)   0x1e22     32     hard     yes     yes     yes
  Lynx Point (PCH)      0x8c22     32     hard     yes     yes     yes
  Lynx Point-LP (PCH)   0x9c22     32     hard     yes     yes     yes

  Features supported by this driver:
  Software PEC                     no
  Hardware PEC                     yes
  Block buffer                     yes
  Block process call transaction   no
  I2C block read transaction       yes  (doesn't use the block buffer)
  Slave mode                       no
  Interrupt processing             yes

  See the file Documentation/i2c/busses/i2c-i801 for details.
*/

#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/stddef.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/acpi.h>
#include <linux/io.h>
#include <linux/dmi.h>
#include <linux/slab.h>
#include <linux/wait.h>
#include <linux/err.h>
#include <linux/of_i2c.h>

#if (defined CONFIG_I2C_MUX_GPIO || defined CONFIG_I2C_MUX_GPIO_MODULE) && \
		defined CONFIG_DMI
#include <linux/gpio.h>
#include <linux/i2c-mux-gpio.h>
#include <linux/platform_device.h>
#endif

/* I801 SMBus address offsets */
#define SMBHSTSTS(p)	(0 + (p)->smba)
#define SMBHSTCNT(p)	(2 + (p)->smba)
#define SMBHSTCMD(p)	(3 + (p)->smba)
#define SMBHSTADD(p)	(4 + (p)->smba)
#define SMBHSTDAT0(p)	(5 + (p)->smba)
#define SMBHSTDAT1(p)	(6 + (p)->smba)
#define SMBBLKDAT(p)	(7 + (p)->smba)
#define SMBPEC(p)	(8 + (p)->smba)		/* ICH3 and later */
#define SMBAUXSTS(p)	(12 + (p)->smba)	/* ICH4 and later */
#define SMBAUXCTL(p)	(13 + (p)->smba)	/* ICH4 and later */

/* PCI Address Constants */
#define SMBBAR		4
#define SMBPCISTS	0x006
#define SMBHSTCFG	0x040

/* Host status bits for SMBPCISTS */
#define SMBPCISTS_INTS		0x08

/* Host configuration bits for SMBHSTCFG */
#define SMBHSTCFG_HST_EN	1
#define SMBHSTCFG_SMB_SMI_EN	2
#define SMBHSTCFG_I2C_EN	4

/* Auxiliary control register bits, ICH4+ only */
#define SMBAUXCTL_CRC		1
#define SMBAUXCTL_E32B		2

/* Other settings */
#define MAX_RETRIES		400

/* I801 command constants */
#define I801_QUICK		0x00
#define I801_BYTE		0x04
#define I801_BYTE_DATA		0x08
#define I801_WORD_DATA		0x0C
#define I801_PROC_CALL		0x10	/* unimplemented */
#define I801_BLOCK_DATA		0x14
#define I801_I2C_BLOCK_DATA	0x18	/* ICH5 and later */

/* I801 Host Control register bits */
#define SMBHSTCNT_INTREN	0x01
#define SMBHSTCNT_KILL		0x02
#define SMBHSTCNT_LAST_BYTE	0x20
#define SMBHSTCNT_START		0x40
#define SMBHSTCNT_PEC_EN	0x80	/* ICH3 and later */

/* I801 Hosts Status register bits */
#define SMBHSTSTS_BYTE_DONE	0x80
#define SMBHSTSTS_INUSE_STS	0x40
#define SMBHSTSTS_SMBALERT_STS	0x20
#define SMBHSTSTS_FAILED	0x10
#define SMBHSTSTS_BUS_ERR	0x08
#define SMBHSTSTS_DEV_ERR	0x04
#define SMBHSTSTS_INTR		0x02
#define SMBHSTSTS_HOST_BUSY	0x01

#define STATUS_ERROR_FLAGS	(SMBHSTSTS_FAILED | SMBHSTSTS_BUS_ERR | \
				 SMBHSTSTS_DEV_ERR)

#define STATUS_FLAGS		(SMBHSTSTS_BYTE_DONE | SMBHSTSTS_INTR | \
				 STATUS_ERROR_FLAGS)

/* Older devices have their ID defined in <linux/pci_ids.h> */
#define PCI_DEVICE_ID_INTEL_COUGARPOINT_SMBUS	0x1c22
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS	0x1d22
/* Patsburg also has three 'Integrated Device Function' SMBus controllers */
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF0	0x1d70
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF1	0x1d71
#define PCI_DEVICE_ID_INTEL_PATSBURG_SMBUS_IDF2	0x1d72
#define PCI_DEVICE_ID_INTEL_PANTHERPOINT_SMBUS	0x1e22
#define PCI_DEVICE_ID_INTEL_DH89XXCC_SMBUS	0x2330
#define PCI_DEVICE_ID_INTEL_5_3400_SERIES_SMBUS	0x3b30
#define PCI_DEVICE_ID_INTEL_LYNXPOINT_SMBUS	0x8c22
#define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS	0x9c22

struct i801_mux_config {
	char *gpio_chip;
	unsigned values[3];
	int