cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

lm78.c (27370B)


      1// SPDX-License-Identifier: GPL-2.0-or-later
      2/*
      3 * lm78.c - Part of lm_sensors, Linux kernel modules for hardware
      4 *	    monitoring
      5 * Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>
      6 * Copyright (c) 2007, 2011  Jean Delvare <jdelvare@suse.de>
      7 */
      8
      9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
     10
     11#include <linux/module.h>
     12#include <linux/init.h>
     13#include <linux/slab.h>
     14#include <linux/jiffies.h>
     15#include <linux/i2c.h>
     16#include <linux/hwmon.h>
     17#include <linux/hwmon-vid.h>
     18#include <linux/hwmon-sysfs.h>
     19#include <linux/err.h>
     20#include <linux/mutex.h>
     21
     22#ifdef CONFIG_ISA
     23#include <linux/platform_device.h>
     24#include <linux/ioport.h>
     25#include <linux/io.h>
     26#endif
     27
     28/* Addresses to scan */
     29static const unsigned short normal_i2c[] = { 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d,
     30						0x2e, 0x2f, I2C_CLIENT_END };
     31enum chips { lm78, lm79 };
     32
     33/* Many LM78 constants specified below */
     34
     35/* Length of ISA address segment */
     36#define LM78_EXTENT 8
     37
     38/* Where are the ISA address/data registers relative to the base address */
     39#define LM78_ADDR_REG_OFFSET 5
     40#define LM78_DATA_REG_OFFSET 6
     41
     42/* The LM78 registers */
     43#define LM78_REG_IN_MAX(nr) (0x2b + (nr) * 2)
     44#define LM78_REG_IN_MIN(nr) (0x2c + (nr) * 2)
     45#define LM78_REG_IN(nr) (0x20 + (nr))
     46
     47#define LM78_REG_FAN_MIN(nr) (0x3b + (nr))
     48#define LM78_REG_FAN(nr) (0x28 + (nr))
     49
     50#define LM78_REG_TEMP 0x27
     51#define LM78_REG_TEMP_OVER 0x39
     52#define LM78_REG_TEMP_HYST 0x3a
     53
     54#define LM78_REG_ALARM1 0x41
     55#define LM78_REG_ALARM2 0x42
     56
     57#define LM78_REG_VID_FANDIV 0x47
     58
     59#define LM78_REG_CONFIG 0x40
     60#define LM78_REG_CHIPID 0x49
     61#define LM78_REG_I2C_ADDR 0x48
     62
     63/*
     64 * Conversions. Rounding and limit checking is only done on the TO_REG
     65 * variants.
     66 */
     67
     68/*
     69 * IN: mV (0V to 4.08V)
     70 * REG: 16mV/bit
     71 */
     72static inline u8 IN_TO_REG(unsigned long val)
     73{
     74	unsigned long nval = clamp_val(val, 0, 4080);
     75	return (nval + 8) / 16;
     76}
     77#define IN_FROM_REG(val) ((val) *  16)
     78
     79static inline u8 FAN_TO_REG(long rpm, int div)
     80{
     81	if (rpm <= 0)
     82		return 255;
     83	if (rpm > 1350000)
     84		return 1;
     85	return clamp_val((1350000 + rpm * div / 2) / (rpm * div), 1, 254);
     86}
     87
     88static inline int FAN_FROM_REG(u8 val, int div)
     89{
     90	return val == 0 ? -1 : val == 255 ? 0 : 1350000 / (val * div);
     91}
     92
     93/*
     94 * TEMP: mC (-128C to +127C)
     95 * REG: 1C/bit, two's complement
     96 */
     97static inline s8 TEMP_TO_REG(long val)
     98{
     99	int nval = clamp_val(val, -128000, 127000) ;
    100	return nval < 0 ? (nval - 500) / 1000 : (nval + 500) / 1000;
    101}
    102
    103static inline int TEMP_FROM_REG(s8 val)
    104{
    105	return val * 1000;
    106}
    107
    108#define DIV_FROM_REG(val) (1 << (val))
    109
    110struct lm78_data {
    111	struct i2c_client *client;
    112	struct mutex lock;
    113	enum chips type;
    114
    115	/* For ISA device only */
    116	const char *name;
    117	int isa_addr;
    118
    119	struct mutex update_lock;
    120	bool valid;		/* true if following fields are valid */
    121	unsigned long last_updated;	/* In jiffies */
    122
    123	u8 in[7];		/* Register value */
    124	u8 in_max[7];		/* Register value */
    125	u8 in_min[7];		/* Register value */
    126	u8 fan[3];		/* Register value */
    127	u8 fan_min[3];		/* Register value */
    128	s8 temp;		/* Register value */
    129	s8 temp_over;		/* Register value */
    130	s8 temp_hyst;		/* Register value */
    131	u8 fan_div[3];		/* Register encoding, shifted right */
    132	u8 vid;			/* Register encoding, combined */
    133	u16 alarms;		/* Register encoding, combined */
    134};
    135
    136static int lm78_read_value(struct lm78_data *data, u8 reg);
    137static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value);
    138static struct lm78_data *lm78_update_device(struct device *dev);
    139static void lm78_init_device(struct lm78_data *data);
    140
    141/* 7 Voltages */
    142static ssize_t in_show(struct device *dev, struct device_attribute *da,
    143		       char *buf)
    144{
    145	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    146	struct lm78_data *data = lm78_update_device(dev);
    147	return sprintf(buf, "%d\n", IN_FROM_REG(data->in[attr->index]));
    148}
    149
    150static ssize_t in_min_show(struct device *dev, struct device_attribute *da,
    151			   char *buf)
    152{
    153	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    154	struct lm78_data *data = lm78_update_device(dev);
    155	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_min[attr->index]));
    156}
    157
    158static ssize_t in_max_show(struct device *dev, struct device_attribute *da,
    159			   char *buf)
    160{
    161	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    162	struct lm78_data *data = lm78_update_device(dev);
    163	return sprintf(buf, "%d\n", IN_FROM_REG(data->in_max[attr->index]));
    164}
    165
    166static ssize_t in_min_store(struct device *dev, struct device_attribute *da,
    167			    const char *buf, size_t count)
    168{
    169	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    170	struct lm78_data *data = dev_get_drvdata(dev);
    171	int nr = attr->index;
    172	unsigned long val;
    173	int err;
    174
    175	err = kstrtoul(buf, 10, &val);
    176	if (err)
    177		return err;
    178
    179	mutex_lock(&data->update_lock);
    180	data->in_min[nr] = IN_TO_REG(val);
    181	lm78_write_value(data, LM78_REG_IN_MIN(nr), data->in_min[nr]);
    182	mutex_unlock(&data->update_lock);
    183	return count;
    184}
    185
    186static ssize_t in_max_store(struct device *dev, struct device_attribute *da,
    187			    const char *buf, size_t count)
    188{
    189	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    190	struct lm78_data *data = dev_get_drvdata(dev);
    191	int nr = attr->index;
    192	unsigned long val;
    193	int err;
    194
    195	err = kstrtoul(buf, 10, &val);
    196	if (err)
    197		return err;
    198
    199	mutex_lock(&data->update_lock);
    200	data->in_max[nr] = IN_TO_REG(val);
    201	lm78_write_value(data, LM78_REG_IN_MAX(nr), data->in_max[nr]);
    202	mutex_unlock(&data->update_lock);
    203	return count;
    204}
    205
    206static SENSOR_DEVICE_ATTR_RO(in0_input, in, 0);
    207static SENSOR_DEVICE_ATTR_RW(in0_min, in_min, 0);
    208static SENSOR_DEVICE_ATTR_RW(in0_max, in_max, 0);
    209static SENSOR_DEVICE_ATTR_RO(in1_input, in, 1);
    210static SENSOR_DEVICE_ATTR_RW(in1_min, in_min, 1);
    211static SENSOR_DEVICE_ATTR_RW(in1_max, in_max, 1);
    212static SENSOR_DEVICE_ATTR_RO(in2_input, in, 2);
    213static SENSOR_DEVICE_ATTR_RW(in2_min, in_min, 2);
    214static SENSOR_DEVICE_ATTR_RW(in2_max, in_max, 2);
    215static SENSOR_DEVICE_ATTR_RO(in3_input, in, 3);
    216static SENSOR_DEVICE_ATTR_RW(in3_min, in_min, 3);
    217static SENSOR_DEVICE_ATTR_RW(in3_max, in_max, 3);
    218static SENSOR_DEVICE_ATTR_RO(in4_input, in, 4);
    219static SENSOR_DEVICE_ATTR_RW(in4_min, in_min, 4);
    220static SENSOR_DEVICE_ATTR_RW(in4_max, in_max, 4);
    221static SENSOR_DEVICE_ATTR_RO(in5_input, in, 5);
    222static SENSOR_DEVICE_ATTR_RW(in5_min, in_min, 5);
    223static SENSOR_DEVICE_ATTR_RW(in5_max, in_max, 5);
    224static SENSOR_DEVICE_ATTR_RO(in6_input, in, 6);
    225static SENSOR_DEVICE_ATTR_RW(in6_min, in_min, 6);
    226static SENSOR_DEVICE_ATTR_RW(in6_max, in_max, 6);
    227
    228/* Temperature */
    229static ssize_t temp1_input_show(struct device *dev,
    230				struct device_attribute *da, char *buf)
    231{
    232	struct lm78_data *data = lm78_update_device(dev);
    233	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp));
    234}
    235
    236static ssize_t temp1_max_show(struct device *dev, struct device_attribute *da,
    237			      char *buf)
    238{
    239	struct lm78_data *data = lm78_update_device(dev);
    240	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_over));
    241}
    242
    243static ssize_t temp1_max_store(struct device *dev,
    244			       struct device_attribute *da, const char *buf,
    245			       size_t count)
    246{
    247	struct lm78_data *data = dev_get_drvdata(dev);
    248	long val;
    249	int err;
    250
    251	err = kstrtol(buf, 10, &val);
    252	if (err)
    253		return err;
    254
    255	mutex_lock(&data->update_lock);
    256	data->temp_over = TEMP_TO_REG(val);
    257	lm78_write_value(data, LM78_REG_TEMP_OVER, data->temp_over);
    258	mutex_unlock(&data->update_lock);
    259	return count;
    260}
    261
    262static ssize_t temp1_max_hyst_show(struct device *dev,
    263				   struct device_attribute *da, char *buf)
    264{
    265	struct lm78_data *data = lm78_update_device(dev);
    266	return sprintf(buf, "%d\n", TEMP_FROM_REG(data->temp_hyst));
    267}
    268
    269static ssize_t temp1_max_hyst_store(struct device *dev,
    270				    struct device_attribute *da,
    271				    const char *buf, size_t count)
    272{
    273	struct lm78_data *data = dev_get_drvdata(dev);
    274	long val;
    275	int err;
    276
    277	err = kstrtol(buf, 10, &val);
    278	if (err)
    279		return err;
    280
    281	mutex_lock(&data->update_lock);
    282	data->temp_hyst = TEMP_TO_REG(val);
    283	lm78_write_value(data, LM78_REG_TEMP_HYST, data->temp_hyst);
    284	mutex_unlock(&data->update_lock);
    285	return count;
    286}
    287
    288static DEVICE_ATTR_RO(temp1_input);
    289static DEVICE_ATTR_RW(temp1_max);
    290static DEVICE_ATTR_RW(temp1_max_hyst);
    291
    292/* 3 Fans */
    293static ssize_t fan_show(struct device *dev, struct device_attribute *da,
    294			char *buf)
    295{
    296	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    297	struct lm78_data *data = lm78_update_device(dev);
    298	int nr = attr->index;
    299	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan[nr],
    300		DIV_FROM_REG(data->fan_div[nr])));
    301}
    302
    303static ssize_t fan_min_show(struct device *dev, struct device_attribute *da,
    304			    char *buf)
    305{
    306	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    307	struct lm78_data *data = lm78_update_device(dev);
    308	int nr = attr->index;
    309	return sprintf(buf, "%d\n", FAN_FROM_REG(data->fan_min[nr],
    310		DIV_FROM_REG(data->fan_div[nr])));
    311}
    312
    313static ssize_t fan_min_store(struct device *dev, struct device_attribute *da,
    314			     const char *buf, size_t count)
    315{
    316	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    317	struct lm78_data *data = dev_get_drvdata(dev);
    318	int nr = attr->index;
    319	unsigned long val;
    320	int err;
    321
    322	err = kstrtoul(buf, 10, &val);
    323	if (err)
    324		return err;
    325
    326	mutex_lock(&data->update_lock);
    327	data->fan_min[nr] = FAN_TO_REG(val, DIV_FROM_REG(data->fan_div[nr]));
    328	lm78_write_value(data, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
    329	mutex_unlock(&data->update_lock);
    330	return count;
    331}
    332
    333static ssize_t fan_div_show(struct device *dev, struct device_attribute *da,
    334			    char *buf)
    335{
    336	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    337	struct lm78_data *data = lm78_update_device(dev);
    338	return sprintf(buf, "%d\n", DIV_FROM_REG(data->fan_div[attr->index]));
    339}
    340
    341/*
    342 * Note: we save and restore the fan minimum here, because its value is
    343 * determined in part by the fan divisor.  This follows the principle of
    344 * least surprise; the user doesn't expect the fan minimum to change just
    345 * because the divisor changed.
    346 */
    347static ssize_t fan_div_store(struct device *dev, struct device_attribute *da,
    348			     const char *buf, size_t count)
    349{
    350	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
    351	struct lm78_data *data = dev_get_drvdata(dev);
    352	int nr = attr->index;
    353	unsigned long min;
    354	u8 reg;
    355	unsigned long val;
    356	int err;
    357
    358	err = kstrtoul(buf, 10, &val);
    359	if (err)
    360		return err;
    361
    362	mutex_lock(&data->update_lock);
    363	min = FAN_FROM_REG(data->fan_min[nr],
    364			   DIV_FROM_REG(data->fan_div[nr]));
    365
    366	switch (val) {
    367	case 1:
    368		data->fan_div[nr] = 0;
    369		break;
    370	case 2:
    371		data->fan_div[nr] = 1;
    372		break;
    373	case 4:
    374		data->fan_div[nr] = 2;
    375		break;
    376	case 8:
    377		data->fan_div[nr] = 3;
    378		break;
    379	default:
    380		dev_err(dev,
    381			"fan_div value %ld not supported. Choose one of 1, 2, 4 or 8!\n",
    382			val);
    383		mutex_unlock(&data->update_lock);
    384		return -EINVAL;
    385	}
    386
    387	reg = lm78_read_value(data, LM78_REG_VID_FANDIV);
    388	switch (nr) {
    389	case 0:
    390		reg = (reg & 0xcf) | (data->fan_div[nr] << 4);
    391		break;
    392	case 1:
    393		reg = (reg & 0x3f) | (data->fan_div[nr] << 6);
    394		break;
    395	}
    396	lm78_write_value(data, LM78_REG_VID_FANDIV, reg);
    397
    398	data->fan_min[nr] =
    399		FAN_TO_REG(min, DIV_FROM_REG(data->fan_div[nr]));
    400	lm78_write_value(data, LM78_REG_FAN_MIN(nr), data->fan_min[nr]);
    401	mutex_unlock(&data->update_lock);
    402
    403	return count;
    404}
    405
    406static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, 0);
    407static SENSOR_DEVICE_ATTR_RW(fan1_min, fan_min, 0);
    408static SENSOR_DEVICE_ATTR_RO(fan2_input, fan, 1);
    409static SENSOR_DEVICE_ATTR_RW(fan2_min, fan_min, 1);
    410static SENSOR_DEVICE_ATTR_RO(fan3_input, fan, 2);
    411static SENSOR_DEVICE_ATTR_RW(fan3_min, fan_min, 2);
    412
    413/* Fan 3 divisor is locked in H/W */
    414static SENSOR_DEVICE_ATTR_RW(fan1_div, fan_div, 0);
    415static SENSOR_DEVICE_ATTR_RW(fan2_div, fan_div, 1);
    416static SENSOR_DEVICE_ATTR_RO(fan3_div, fan_div, 2);
    417
    418/* VID */
    419static ssize_t cpu0_vid_show(struct device *dev, struct device_attribute *da,
    420			     char *buf)
    421{
    422	struct lm78_data *data = lm78_update_device(dev);
    423	return sprintf(buf, "%d\n", vid_from_reg(data->vid, 82));
    424}
    425static DEVICE_ATTR_RO(cpu0_vid);
    426
    427/* Alarms */
    428static ssize_t alarms_show(struct device *dev, struct device_attribute *da,
    429			   char *buf)
    430{
    431	struct lm78_data *data = lm78_update_device(dev);
    432	return sprintf(buf, "%u\n", data->alarms);
    433}
    434static DEVICE_ATTR_RO(alarms);
    435
    436static ssize_t alarm_show(struct device *dev, struct device_attribute *da,
    437			  char *buf)
    438{
    439	struct lm78_data *data = lm78_update_device(dev);
    440	int nr = to_sensor_dev_attr(da)->index;
    441	return sprintf(buf, "%u\n", (data->alarms >> nr) & 1);
    442}
    443static SENSOR_DEVICE_ATTR_RO(in0_alarm, alarm, 0);
    444static SENSOR_DEVICE_ATTR_RO(in1_alarm, alarm, 1);
    445static SENSOR_DEVICE_ATTR_RO(in2_alarm, alarm, 2);
    446static SENSOR_DEVICE_ATTR_RO(in3_alarm, alarm, 3);
    447static SENSOR_DEVICE_ATTR_RO(in4_alarm, alarm, 8);
    448static SENSOR_DEVICE_ATTR_RO(in5_alarm, alarm, 9);
    449static SENSOR_DEVICE_ATTR_RO(in6_alarm, alarm, 10);
    450static SENSOR_DEVICE_ATTR_RO(fan1_alarm, alarm, 6);
    451static SENSOR_DEVICE_ATTR_RO(fan2_alarm, alarm, 7);
    452static SENSOR_DEVICE_ATTR_RO(fan3_alarm, alarm, 11);
    453static SENSOR_DEVICE_ATTR_RO(temp1_alarm, alarm, 4);
    454
    455static struct attribute *lm78_attrs[] = {
    456	&sensor_dev_attr_in0_input.dev_attr.attr,
    457	&sensor_dev_attr_in0_min.dev_attr.attr,
    458	&sensor_dev_attr_in0_max.dev_attr.attr,
    459	&sensor_dev_attr_in0_alarm.dev_attr.attr,
    460	&sensor_dev_attr_in1_input.dev_attr.attr,
    461	&sensor_dev_attr_in1_min.dev_attr.attr,
    462	&sensor_dev_attr_in1_max.dev_attr.attr,
    463	&sensor_dev_attr_in1_alarm.dev_attr.attr,
    464	&sensor_dev_attr_in2_input.dev_attr.attr,
    465	&sensor_dev_attr_in2_min.dev_attr.attr,
    466	&sensor_dev_attr_in2_max.dev_attr.attr,
    467	&sensor_dev_attr_in2_alarm.dev_attr.attr,
    468	&sensor_dev_attr_in3_input.dev_attr.attr,
    469	&sensor_dev_attr_in3_min.dev_attr.attr,
    470	&sensor_dev_attr_in3_max.dev_attr.attr,
    471	&sensor_dev_attr_in3_alarm.dev_attr.attr,
    472	&sensor_dev_attr_in4_input.dev_attr.attr,
    473	&sensor_dev_attr_in4_min.dev_attr.attr,
    474	&sensor_dev_attr_in4_max.dev_attr.attr,
    475	&sensor_dev_attr_in4_alarm.dev_attr.attr,
    476	&sensor_dev_attr_in5_input.dev_attr.attr,
    477	&sensor_dev_attr_in5_min.dev_attr.attr,
    478	&sensor_dev_attr_in5_max.dev_attr.attr,
    479	&sensor_dev_attr_in5_alarm.dev_attr.attr,
    480	&sensor_dev_attr_in6_input.dev_attr.attr,
    481	&sensor_dev_attr_in6_min.dev_attr.attr,
    482	&sensor_dev_attr_in6_max.dev_attr.attr,
    483	&sensor_dev_attr_in6_alarm.dev_attr.attr,
    484	&dev_attr_temp1_input.attr,
    485	&dev_attr_temp1_max.attr,
    486	&dev_attr_temp1_max_hyst.attr,
    487	&sensor_dev_attr_temp1_alarm.dev_attr.attr,
    488	&sensor_dev_attr_fan1_input.dev_attr.attr,
    489	&sensor_dev_attr_fan1_min.dev_attr.attr,
    490	&sensor_dev_attr_fan1_div.dev_attr.attr,
    491	&sensor_dev_attr_fan1_alarm.dev_attr.attr,
    492	&sensor_dev_attr_fan2_input.dev_attr.attr,
    493	&sensor_dev_attr_fan2_min.dev_attr.attr,
    494	&sensor_dev_attr_fan2_div.dev_attr.attr,
    495	&sensor_dev_attr_fan2_alarm.dev_attr.attr,
    496	&sensor_dev_attr_fan3_input.dev_attr.attr,
    497	&sensor_dev_attr_fan3_min.dev_attr.attr,
    498	&sensor_dev_attr_fan3_div.dev_attr.attr,
    499	&sensor_dev_attr_fan3_alarm.dev_attr.attr,
    500	&dev_attr_alarms.attr,
    501	&dev_attr_cpu0_vid.attr,
    502
    503	NULL
    504};
    505
    506ATTRIBUTE_GROUPS(lm78);
    507
    508/*
    509 * ISA related code
    510 */
    511#ifdef CONFIG_ISA
    512
    513/* ISA device, if found */
    514static struct platform_device *pdev;
    515
    516static unsigned short isa_address = 0x290;
    517
    518static struct lm78_data *lm78_data_if_isa(void)
    519{
    520	return pdev ? platform_get_drvdata(pdev) : NULL;
    521}
    522
    523/* Returns 1 if the I2C chip appears to be an alias of the ISA chip */
    524static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
    525{
    526	struct lm78_data *isa;
    527	int i;
    528
    529	if (!pdev)	/* No ISA chip */
    530		return 0;
    531	isa = platform_get_drvdata(pdev);
    532
    533	if (lm78_read_value(isa, LM78_REG_I2C_ADDR) != client->addr)
    534		return 0;	/* Address doesn't match */
    535	if ((lm78_read_value(isa, LM78_REG_CHIPID) & 0xfe) != (chipid & 0xfe))
    536		return 0;	/* Chip type doesn't match */
    537
    538	/*
    539	 * We compare all the limit registers, the config register and the
    540	 * interrupt mask registers
    541	 */
    542	for (i = 0x2b; i <= 0x3d; i++) {
    543		if (lm78_read_value(isa, i) !=
    544		    i2c_smbus_read_byte_data(client, i))
    545			return 0;
    546	}
    547	if (lm78_read_value(isa, LM78_REG_CONFIG) !=
    548	    i2c_smbus_read_byte_data(client, LM78_REG_CONFIG))
    549		return 0;
    550	for (i = 0x43; i <= 0x46; i++) {
    551		if (lm78_read_value(isa, i) !=
    552		    i2c_smbus_read_byte_data(client, i))
    553			return 0;
    554	}
    555
    556	return 1;
    557}
    558#else /* !CONFIG_ISA */
    559
    560static int lm78_alias_detect(struct i2c_client *client, u8 chipid)
    561{
    562	return 0;
    563}
    564
    565static struct lm78_data *lm78_data_if_isa(void)
    566{
    567	return NULL;
    568}
    569#endif /* CONFIG_ISA */
    570
    571static int lm78_i2c_detect(struct i2c_client *client,
    572			   struct i2c_board_info *info)
    573{
    574	int i;
    575	struct lm78_data *isa = lm78_data_if_isa();
    576	const char *client_name;
    577	struct i2c_adapter *adapter = client->adapter;
    578	int address = client->addr;
    579
    580	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
    581		return -ENODEV;
    582
    583	/*
    584	 * We block updates of the ISA device to minimize the risk of
    585	 * concurrent access to the same LM78 chip through different
    586	 * interfaces.
    587	 */
    588	if (isa)
    589		mutex_lock(&isa->update_lock);
    590
    591	if ((i2c_smbus_read_byte_data(client, LM78_REG_CONFIG) & 0x80)
    592	 || i2c_smbus_read_byte_data(client, LM78_REG_I2C_ADDR) != address)
    593		goto err_nodev;
    594
    595	/* Explicitly prevent the misdetection of Winbond chips */
    596	i = i2c_smbus_read_byte_data(client, 0x4f);
    597	if (i == 0xa3 || i == 0x5c)
    598		goto err_nodev;
    599
    600	/* Determine the chip type. */
    601	i = i2c_smbus_read_byte_data(client, LM78_REG_CHIPID);
    602	if (i == 0x00 || i == 0x20	/* LM78 */
    603	 || i == 0x40)			/* LM78-J */
    604		client_name = "lm78";
    605	else if ((i & 0xfe) == 0xc0)
    606		client_name = "lm79";
    607	else
    608		goto err_nodev;
    609
    610	if (lm78_alias_detect(client, i)) {
    611		dev_dbg(&adapter->dev,
    612			"Device at 0x%02x appears to be the same as ISA device\n",
    613			address);
    614		goto err_nodev;
    615	}
    616
    617	if (isa)
    618		mutex_unlock(&isa->update_lock);
    619
    620	strlcpy(info->type, client_name, I2C_NAME_SIZE);
    621
    622	return 0;
    623
    624 err_nodev:
    625	if (isa)
    626		mutex_unlock(&isa->update_lock);
    627	return -ENODEV;
    628}
    629
    630static const struct i2c_device_id lm78_i2c_id[];
    631
    632static int lm78_i2c_probe(struct i2c_client *client)
    633{
    634	struct device *dev = &client->dev;
    635	struct device *hwmon_dev;
    636	struct lm78_data *data;
    637
    638	data = devm_kzalloc(dev, sizeof(struct lm78_data), GFP_KERNEL);
    639	if (!data)
    640		return -ENOMEM;
    641
    642	data->client = client;
    643	data->type = i2c_match_id(lm78_i2c_id, client)->driver_data;
    644
    645	/* Initialize the LM78 chip */
    646	lm78_init_device(data);
    647
    648	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
    649							   data, lm78_groups);
    650	return PTR_ERR_OR_ZERO(hwmon_dev);
    651}
    652
    653static const struct i2c_device_id lm78_i2c_id[] = {
    654	{ "lm78", lm78 },
    655	{ "lm79", lm79 },
    656	{ }
    657};
    658MODULE_DEVICE_TABLE(i2c, lm78_i2c_id);
    659
    660static struct i2c_driver lm78_driver = {
    661	.class		= I2C_CLASS_HWMON,
    662	.driver = {
    663		.name	= "lm78",
    664	},
    665	.probe_new	= lm78_i2c_probe,
    666	.id_table	= lm78_i2c_id,
    667	.detect		= lm78_i2c_detect,
    668	.address_list	= normal_i2c,
    669};
    670
    671/*
    672 * The SMBus locks itself, but ISA access must be locked explicitly!
    673 * We don't want to lock the whole ISA bus, so we lock each client
    674 * separately.
    675 * We ignore the LM78 BUSY flag at this moment - it could lead to deadlocks,
    676 * would slow down the LM78 access and should not be necessary.
    677 */
    678static int lm78_read_value(struct lm78_data *data, u8 reg)
    679{
    680	struct i2c_client *client = data->client;
    681
    682#ifdef CONFIG_ISA
    683	if (!client) { /* ISA device */
    684		int res;
    685		mutex_lock(&data->lock);
    686		outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
    687		res = inb_p(data->isa_addr + LM78_DATA_REG_OFFSET);
    688		mutex_unlock(&data->lock);
    689		return res;
    690	} else
    691#endif
    692		return i2c_smbus_read_byte_data(client, reg);
    693}
    694
    695static int lm78_write_value(struct lm78_data *data, u8 reg, u8 value)
    696{
    697	struct i2c_client *client = data->client;
    698
    699#ifdef CONFIG_ISA
    700	if (!client) { /* ISA device */
    701		mutex_lock(&data->lock);
    702		outb_p(reg, data->isa_addr + LM78_ADDR_REG_OFFSET);
    703		outb_p(value, data->isa_addr + LM78_DATA_REG_OFFSET);
    704		mutex_unlock(&data->lock);
    705		return 0;
    706	} else
    707#endif
    708		return i2c_smbus_write_byte_data(client, reg, value);
    709}
    710
    711static void lm78_init_device(struct lm78_data *data)
    712{
    713	u8 config;
    714	int i;
    715
    716	/* Start monitoring */
    717	config = lm78_read_value(data, LM78_REG_CONFIG);
    718	if ((config & 0x09) != 0x01)
    719		lm78_write_value(data, LM78_REG_CONFIG,
    720				 (config & 0xf7) | 0x01);
    721
    722	/* A few vars need to be filled upon startup */
    723	for (i = 0; i < 3; i++) {
    724		data->fan_min[i] = lm78_read_value(data,
    725					LM78_REG_FAN_MIN(i));
    726	}
    727
    728	mutex_init(&data->update_lock);
    729}
    730
    731static struct lm78_data *lm78_update_device(struct device *dev)
    732{
    733	struct lm78_data *data = dev_get_drvdata(dev);
    734	int i;
    735
    736	mutex_lock(&data->update_lock);
    737
    738	if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
    739	    || !data->valid) {
    740
    741		dev_dbg(dev, "Starting lm78 update\n");
    742
    743		for (i = 0; i <= 6; i++) {
    744			data->in[i] =
    745			    lm78_read_value(data, LM78_REG_IN(i));
    746			data->in_min[i] =
    747			    lm78_read_value(data, LM78_REG_IN_MIN(i));
    748			data->in_max[i] =
    749			    lm78_read_value(data, LM78_REG_IN_MAX(i));
    750		}
    751		for (i = 0; i < 3; i++) {
    752			data->fan[i] =
    753			    lm78_read_value(data, LM78_REG_FAN(i));
    754			data->fan_min[i] =
    755			    lm78_read_value(data, LM78_REG_FAN_MIN(i));
    756		}
    757		data->temp = lm78_read_value(data, LM78_REG_TEMP);
    758		data->temp_over =
    759		    lm78_read_value(data, LM78_REG_TEMP_OVER);
    760		data->temp_hyst =
    761		    lm78_read_value(data, LM78_REG_TEMP_HYST);
    762		i = lm78_read_value(data, LM78_REG_VID_FANDIV);
    763		data->vid = i & 0x0f;
    764		if (data->type == lm79)
    765			data->vid |=
    766			    (lm78_read_value(data, LM78_REG_CHIPID) &
    767			     0x01) << 4;
    768		else
    769			data->vid |= 0x10;
    770		data->fan_div[0] = (i >> 4) & 0x03;
    771		data->fan_div[1] = i >> 6;
    772		data->alarms = lm78_read_value(data, LM78_REG_ALARM1) +
    773		    (lm78_read_value(data, LM78_REG_ALARM2) << 8);
    774		data->last_updated = jiffies;
    775		data->valid = true;
    776
    777		data->fan_div[2] = 1;
    778	}
    779
    780	mutex_unlock(&data->update_lock);
    781
    782	return data;
    783}
    784
    785#ifdef CONFIG_ISA
    786static int lm78_isa_probe(struct platform_device *pdev)
    787{
    788	struct device *dev = &pdev->dev;
    789	struct device *hwmon_dev;
    790	struct lm78_data *data;
    791	struct resource *res;
    792
    793	/* Reserve the ISA region */
    794	res = platform_get_resource(pdev, IORESOURCE_IO, 0);
    795	if (!devm_request_region(dev, res->start + LM78_ADDR_REG_OFFSET,
    796				 2, "lm78"))
    797		return -EBUSY;
    798
    799	data = devm_kzalloc(dev, sizeof(struct lm78_data), GFP_KERNEL);
    800	if (!data)
    801		return -ENOMEM;
    802
    803	mutex_init(&data->lock);
    804	data->isa_addr = res->start;
    805	platform_set_drvdata(pdev, data);
    806
    807	if (lm78_read_value(data, LM78_REG_CHIPID) & 0x80) {
    808		data->type = lm79;
    809		data->name = "lm79";
    810	} else {
    811		data->type = lm78;
    812		data->name = "lm78";
    813	}
    814
    815	/* Initialize the LM78 chip */
    816	lm78_init_device(data);
    817
    818	hwmon_dev = devm_hwmon_device_register_with_groups(dev, data->name,
    819							   data, lm78_groups);
    820	return PTR_ERR_OR_ZERO(hwmon_dev);
    821}
    822
    823static struct platform_driver lm78_isa_driver = {
    824	.driver = {
    825		.name	= "lm78",
    826	},
    827	.probe		= lm78_isa_probe,
    828};
    829
    830/* return 1 if a supported chip is found, 0 otherwise */
    831static int __init lm78_isa_found(unsigned short address)
    832{
    833	int val, save, found = 0;
    834	int port;
    835
    836	/*
    837	 * Some boards declare base+0 to base+7 as a PNP device, some base+4
    838	 * to base+7 and some base+5 to base+6. So we better request each port
    839	 * individually for the probing phase.
    840	 */
    841	for (port = address; port < address + LM78_EXTENT; port++) {
    842		if (!request_region(port, 1, "lm78")) {
    843			pr_debug("Failed to request port 0x%x\n", port);
    844			goto release;
    845		}
    846	}
    847
    848#define REALLY_SLOW_IO
    849	/*
    850	 * We need the timeouts for at least some LM78-like
    851	 * chips. But only if we read 'undefined' registers.
    852	 */
    853	val = inb_p(address + 1);
    854	if (inb_p(address + 2) != val
    855	 || inb_p(address + 3) != val
    856	 || inb_p(address + 7) != val)
    857		goto release;
    858#undef REALLY_SLOW_IO
    859
    860	/*
    861	 * We should be able to change the 7 LSB of the address port. The
    862	 * MSB (busy flag) should be clear initially, set after the write.
    863	 */
    864	save = inb_p(address + LM78_ADDR_REG_OFFSET);
    865	if (save & 0x80)
    866		goto release;
    867	val = ~save & 0x7f;
    868	outb_p(val, address + LM78_ADDR_REG_OFFSET);
    869	if (inb_p(address + LM78_ADDR_REG_OFFSET) != (val | 0x80)) {
    870		outb_p(save, address + LM78_ADDR_REG_OFFSET);
    871		goto release;
    872	}
    873
    874	/* We found a device, now see if it could be an LM78 */
    875	outb_p(LM78_REG_CONFIG, address + LM78_ADDR_REG_OFFSET);
    876	val = inb_p(address + LM78_DATA_REG_OFFSET);
    877	if (val & 0x80)
    878		goto release;
    879	outb_p(LM78_REG_I2C_ADDR, address + LM78_ADDR_REG_OFFSET);
    880	val = inb_p(address + LM78_DATA_REG_OFFSET);
    881	if (val < 0x03 || val > 0x77)	/* Not a valid I2C address */
    882		goto release;
    883
    884	/* The busy flag should be clear again */
    885	if (inb_p(address + LM78_ADDR_REG_OFFSET) & 0x80)
    886		goto release;
    887
    888	/* Explicitly prevent the misdetection of Winbond chips */
    889	outb_p(0x4f, address + LM78_ADDR_REG_OFFSET);
    890	val = inb_p(address + LM78_DATA_REG_OFFSET);
    891	if (val == 0xa3 || val == 0x5c)
    892		goto release;
    893
    894	/* Explicitly prevent the misdetection of ITE chips */
    895	outb_p(0x58, address + LM78_ADDR_REG_OFFSET);
    896	val = inb_p(address + LM78_DATA_REG_OFFSET);
    897	if (val == 0x90)
    898		goto release;
    899
    900	/* Determine the chip type */
    901	outb_p(LM78_REG_CHIPID, address + LM78_ADDR_REG_OFFSET);
    902	val = inb_p(address + LM78_DATA_REG_OFFSET);
    903	if (val == 0x00 || val == 0x20	/* LM78 */
    904	 || val == 0x40			/* LM78-J */
    905	 || (val & 0xfe) == 0xc0)	/* LM79 */
    906		found = 1;
    907
    908	if (found)
    909		pr_info("Found an %s chip at %#x\n",
    910			val & 0x80 ? "LM79" : "LM78", (int)address);
    911
    912 release:
    913	for (port--; port >= address; port--)
    914		release_region(port, 1);
    915	return found;
    916}
    917
    918static int __init lm78_isa_device_add(unsigned short address)
    919{
    920	struct resource res = {
    921		.start	= address,
    922		.end	= address + LM78_EXTENT - 1,
    923		.name	= "lm78",
    924		.flags	= IORESOURCE_IO,
    925	};
    926	int err;
    927
    928	pdev = platform_device_alloc("lm78", address);
    929	if (!pdev) {
    930		err = -ENOMEM;
    931		pr_err("Device allocation failed\n");
    932		goto exit;
    933	}
    934
    935	err = platform_device_add_resources(pdev, &res, 1);
    936	if (err) {
    937		pr_err("Device resource addition failed (%d)\n", err);
    938		goto exit_device_put;
    939	}
    940
    941	err = platform_device_add(pdev);
    942	if (err) {
    943		pr_err("Device addition failed (%d)\n", err);
    944		goto exit_device_put;
    945	}
    946
    947	return 0;
    948
    949 exit_device_put:
    950	platform_device_put(pdev);
    951 exit:
    952	pdev = NULL;
    953	return err;
    954}
    955
    956static int __init lm78_isa_register(void)
    957{
    958	int res;
    959
    960	if (lm78_isa_found(isa_address)) {
    961		res = platform_driver_register(&lm78_isa_driver);
    962		if (res)
    963			goto exit;
    964
    965		/* Sets global pdev as a side effect */
    966		res = lm78_isa_device_add(isa_address);
    967		if (res)
    968			goto exit_unreg_isa_driver;
    969	}
    970
    971	return 0;
    972
    973 exit_unreg_isa_driver:
    974	platform_driver_unregister(&lm78_isa_driver);
    975 exit:
    976	return res;
    977}
    978
    979static void lm78_isa_unregister(void)
    980{
    981	if (pdev) {
    982		platform_device_unregister(pdev);
    983		platform_driver_unregister(&lm78_isa_driver);
    984	}
    985}
    986#else /* !CONFIG_ISA */
    987
    988static int __init lm78_isa_register(void)
    989{
    990	return 0;
    991}
    992
    993static void lm78_isa_unregister(void)
    994{
    995}
    996#endif /* CONFIG_ISA */
    997
    998static int __init sm_lm78_init(void)
    999{
   1000	int res;
   1001
   1002	/*
   1003	 * We register the ISA device first, so that we can skip the
   1004	 * registration of an I2C interface to the same device.
   1005	 */
   1006	res = lm78_isa_register();
   1007	if (res)
   1008		goto exit;
   1009
   1010	res = i2c_add_driver(&lm78_driver);
   1011	if (res)
   1012		goto exit_unreg_isa_device;
   1013
   1014	return 0;
   1015
   1016 exit_unreg_isa_device:
   1017	lm78_isa_unregister();
   1018 exit:
   1019	return res;
   1020}
   1021
   1022static void __exit sm_lm78_exit(void)
   1023{
   1024	lm78_isa_unregister();
   1025	i2c_del_driver(&lm78_driver);
   1026}
   1027
   1028MODULE_AUTHOR("Frodo Looijaard, Jean Delvare <jdelvare@suse.de>");
   1029MODULE_DESCRIPTION("LM78/LM79 driver");
   1030MODULE_LICENSE("GPL");
   1031
   1032module_init(sm_lm78_init);
   1033module_exit(sm_lm78_exit);