path: root/drivers/hwmon/abituguru3.c

/*
    abituguru3.c

    Copyright (c) 2006-2008 Hans de Goede <hdegoede@redhat.com>
    Copyright (c) 2008 Alistair John Strachan <alistair@devzero.co.uk>

    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.
*/
/*
    This driver supports the sensor part of revision 3 of the custom Abit uGuru
    chip found on newer Abit uGuru motherboards. Note: because of lack of specs
    only reading the sensors and their settings is supported.
*/

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/mutex.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/dmi.h>
#include <linux/io.h>

/* uGuru3 bank addresses */
#define ABIT_UGURU3_SETTINGS_BANK		0x01
#define ABIT_UGURU3_SENSORS_BANK		0x08
#define ABIT_UGURU3_MISC_BANK			0x09
#define ABIT_UGURU3_ALARMS_START		0x1E
#define ABIT_UGURU3_SETTINGS_START		0x24
#define ABIT_UGURU3_VALUES_START		0x80
#define ABIT_UGURU3_BOARD_ID			0x0A
/* uGuru3 sensor bank flags */			     /* Alarm if: */
#define ABIT_UGURU3_TEMP_HIGH_ALARM_ENABLE	0x01 /*  temp over warn */
#define ABIT_UGURU3_VOLT_HIGH_ALARM_ENABLE	0x02 /*  volt over max */
#define ABIT_UGURU3_VOLT_LOW_ALARM_ENABLE	0x04 /*  volt under min */
#define ABIT_UGURU3_TEMP_HIGH_ALARM_FLAG	0x10 /* temp is over warn */
#define ABIT_UGURU3_VOLT_HIGH_ALARM_FLAG	0x20 /* volt is over max */
#define ABIT_UGURU3_VOLT_LOW_ALARM_FLAG		0x40 /* volt is under min */
#define ABIT_UGURU3_FAN_LOW_ALARM_ENABLE	0x01 /*   fan under min */
#define ABIT_UGURU3_BEEP_ENABLE			0x08 /* beep if alarm */
#define ABIT_UGURU3_SHUTDOWN_ENABLE		0x80 /* shutdown if alarm */
/* sensor types */
#define ABIT_UGURU3_IN_SENSOR			0
#define ABIT_UGURU3_TEMP_SENSOR			1
#define ABIT_UGURU3_FAN_SENSOR			2

/* Timeouts / Retries, if these turn out to need a lot of fiddling we could
   convert them to params. Determined by trial and error. I assume this is
   cpu-speed independent, since the ISA-bus and not the CPU should be the
   bottleneck. */
#define ABIT_UGURU3_WAIT_TIMEOUT		250
/* Normally the 0xAC at the end of synchronize() is reported after the
   first read, but sometimes not and we need to poll */
#define ABIT_UGURU3_SYNCHRONIZE_TIMEOUT		5
/* utility macros */
#define ABIT_UGURU3_NAME			"abituguru3"
#define ABIT_UGURU3_DEBUG(format, arg...)	\
	if (verbose)				\
		printk(KERN_DEBUG ABIT_UGURU3_NAME ": "	format , ## arg)

/* Macros to help calculate the sysfs_names array length */
#define ABIT_UGURU3_MAX_NO_SENSORS 26
/* sum of strlen +1 of: in??_input\0, in??_{min,max}\0, in??_{min,max}_alarm\0,
   in??_{min,max}_alarm_enable\0, in??_beep\0, in??_shutdown\0, in??_label\0 */
#define ABIT_UGURU3_IN_NAMES_LENGTH (11 + 2 * 9 + 2 * 15 + 2 * 22 + 10 + 14 + 11)
/* sum of strlen +1 of: temp??_input\0, temp??_max\0, temp??_crit\0,
   temp??_alarm\0, temp??_alarm_enable\0, temp??_beep\0, temp??_shutdown\0,
   temp??_label\0 */
#define ABIT_UGURU3_TEMP_NAMES_LENGTH (13 + 11 + 12 + 13 + 20 + 12 + 16 + 13)
/* sum of strlen +1 of: fan??_input\0, fan??_min\0, fan??_alarm\0,
   fan??_alarm_enable\0, fan??_beep\0, fan??_shutdown\0, fan??_label\0 */
#define ABIT_UGURU3_FAN_NAMES_LENGTH (12 + 10 + 12 + 19 + 11 + 15 + 12)
/* Worst case scenario 16 in sensors (longest names_length) and the rest
   temp sensors (second longest names_length). */
#define ABIT_UGURU3_SYSFS_NAMES_LENGTH (16 * ABIT_UGURU3_IN_NAMES_LENGTH + \
	(ABIT_UGURU3_MAX_NO_SENSORS - 16) * ABIT_UGURU3_TEMP_NAMES_LENGTH)

/* All the macros below are named identical to the openguru2 program
   reverse engineered by Louis Kruger, hence the names might not be 100%
   logical. I could come up with better names, but I prefer keeping the names
   identical so that this driver can be compared with his work more easily. */
/* Two i/o-ports are used by uGuru */
#define ABIT_UGURU3_BASE			0x00E0
#define ABIT_UGURU3_CMD				0x00
#define ABIT_UGURU3_DATA			0x04
#define ABIT_UGURU3_REGION_LENGTH		5
/* The wait_xxx functions return this on success and the last contents
   of the DATA register (0-255) on failure. */
#define ABIT_UGURU3_SUCCESS			-1
/* uGuru status flags */
#define ABIT_UGURU3_STATUS_READY_FOR_READ	0x01
#define ABIT_UGURU3_STATUS_BUSY			0x02


/* Structures */
struct abituguru3_sensor_info {
	const char* name;
	int port;
	int type;
	int multiplier;
	int divisor;
	int offset;
};

/* Avoid use of flexible array members */
#define ABIT_UGURU3_MAX_DMI_NAMES 2

struct abituguru3_motherboard_info {
	u16 id;
	const char *dmi_name[ABIT_UGURU3_MAX_DMI_NAMES + 1];
	/* + 1 -> end of sensors indicated by a sensor with name == NULL */
	struct abituguru3_sensor_info sensors[ABIT_UGURU3_MAX_NO_SENSORS + 1];
};

/* For the Abit uGuru, we need to keep some data in memory.
   The structure is dynamically allocated, at the same time when a new
   abituguru3 device is allocated. */
struct abituguru3_data {
	struct device *hwmon_dev;	/* hwmon registered device */
	struct mutex update_lock;	/* protect access to data and uGuru */
	unsigned short addr;		/* uguru base address */
	char valid;			/* !=0 if following fields are valid */
	unsigned long last_updated;	/* In jiffies */

	/* For convenience the sysfs attr and their names are generated
	   automatically. We have max 10 entries per sensor (for in sensors) */
	struct sensor_device_attribute_2 sysfs_attr[ABIT_UGURU3_MAX_NO_SENSORS
		* 10];

	/* Buffer to store the dynamically generated sysfs names */