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Release 4.14 drivers/sbus/char/envctrl.c

/* envctrl.c: Temperature and Fan monitoring on Machines providing it.
 *
 * Copyright (C) 1998  Eddie C. Dost  (ecd@skynet.be)
 * Copyright (C) 2000  Vinh Truong    (vinh.truong@eng.sun.com)
 * VT - The implementation is to support Sun Microelectronics (SME) platform
 *      environment monitoring.  SME platforms use pcf8584 as the i2c bus 
 *      controller to access pcf8591 (8-bit A/D and D/A converter) and 
 *      pcf8571 (256 x 8-bit static low-voltage RAM with I2C-bus interface).
 *      At board level, it follows SME Firmware I2C Specification. Reference:
 *      http://www-eu2.semiconductors.com/pip/PCF8584P
 *      http://www-eu2.semiconductors.com/pip/PCF8574AP
 *      http://www-eu2.semiconductors.com/pip/PCF8591P
 *
 * EB - Added support for CP1500 Global Address and PS/Voltage monitoring.
 *              Eric Brower <ebrower@usa.net>
 *
 * DB - Audit every copy_to_user in envctrl_read.
 *              Daniele Bellucci <bellucda@tiscali.it>
 */

#include <linux/module.h>
#include <linux/kthread.h>
#include <linux/delay.h>
#include <linux/ioport.h>
#include <linux/miscdevice.h>
#include <linux/kmod.h>
#include <linux/reboot.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <linux/uaccess.h>
#include <asm/envctrl.h>
#include <asm/io.h>


#define DRIVER_NAME	"envctrl"

#define PFX		DRIVER_NAME ": "


#define ENVCTRL_MINOR	162


#define PCF8584_ADDRESS	0x55


#define CONTROL_PIN	0x80

#define CONTROL_ES0	0x40

#define CONTROL_ES1	0x20

#define CONTROL_ES2	0x10

#define CONTROL_ENI	0x08

#define CONTROL_STA	0x04

#define CONTROL_STO	0x02

#define CONTROL_ACK	0x01


#define STATUS_PIN	0x80

#define STATUS_STS	0x20

#define STATUS_BER	0x10

#define STATUS_LRB	0x08

#define STATUS_AD0	0x08

#define STATUS_AAB	0x04

#define STATUS_LAB	0x02

#define STATUS_BB	0x01

/*
 * CLK Mode Register.
 */

#define BUS_CLK_90	0x00

#define BUS_CLK_45	0x01

#define BUS_CLK_11	0x02

#define BUS_CLK_1_5	0x03


#define CLK_3		0x00

#define CLK_4_43	0x10

#define CLK_6		0x14

#define CLK_8		0x18

#define CLK_12		0x1c


#define OBD_SEND_START	0xc5    
/* value to generate I2c_bus START condition */

#define OBD_SEND_STOP 	0xc3    
/* value to generate I2c_bus STOP condition */

/* Monitor type of i2c child device.
 * Firmware definitions.
 */

#define PCF8584_MAX_CHANNELS            8

#define PCF8584_GLOBALADDR_TYPE			6  
/* global address monitor */

#define PCF8584_FANSTAT_TYPE            3  
/* fan status monitor */

#define PCF8584_VOLTAGE_TYPE            2  
/* voltage monitor    */

#define PCF8584_TEMP_TYPE	        	1  
/* temperature monitor*/

/* Monitor type of i2c child device.
 * Driver definitions.
 */

#define ENVCTRL_NOMON				0

#define ENVCTRL_CPUTEMP_MON			1    
/* cpu temperature monitor */

#define ENVCTRL_CPUVOLTAGE_MON	  	2    
/* voltage monitor         */

#define ENVCTRL_FANSTAT_MON  		3    
/* fan status monitor      */

#define ENVCTRL_ETHERTEMP_MON		4    
/* ethernet temperature */
					     /* monitor                     */

#define ENVCTRL_VOLTAGESTAT_MON	  	5    
/* voltage status monitor  */

#define ENVCTRL_MTHRBDTEMP_MON		6    
/* motherboard temperature */

#define ENVCTRL_SCSITEMP_MON		7    
/* scsi temperature */

#define ENVCTRL_GLOBALADDR_MON		8    
/* global address */

/* Child device type.
 * Driver definitions.
 */

#define I2C_ADC				0    
/* pcf8591 */

#define I2C_GPIO			1    
/* pcf8571 */

/* Data read from child device may need to decode
 * through a data table and a scale.
 * Translation type as defined by firmware.
 */

#define ENVCTRL_TRANSLATE_NO		0

#define ENVCTRL_TRANSLATE_PARTIAL	1

#define ENVCTRL_TRANSLATE_COMBINED	2

#define ENVCTRL_TRANSLATE_FULL		3     
/* table[data] */

#define ENVCTRL_TRANSLATE_SCALE		4     
/* table[data]/scale */

/* Driver miscellaneous definitions. */

#define ENVCTRL_MAX_CPU			4

#define CHANNEL_DESC_SZ			256

/* Mask values for combined GlobalAddress/PowerStatus node */

#define ENVCTRL_GLOBALADDR_ADDR_MASK 	0x1F

#define ENVCTRL_GLOBALADDR_PSTAT_MASK	0x60

/* Node 0x70 ignored on CompactPCI CP1400/1500 platforms 
 * (see envctrl_init_i2c_child)
 */

#define ENVCTRL_CPCI_IGNORED_NODE		0x70


#define PCF8584_DATA	0x00

#define PCF8584_CSR	0x01

/* Each child device can be monitored by up to PCF8584_MAX_CHANNELS.
 * Property of a port or channel as defined by the firmware.
 */

struct pcf8584_channel {
        
unsigned char chnl_no;
        
unsigned char io_direction;
        
unsigned char type;
        
unsigned char last;
};

/* Each child device may have one or more tables of bytes to help decode
 * data. Table property as defined by the firmware.
 */ 

struct pcf8584_tblprop {
        
unsigned int type;
        
unsigned int scale;  
        
unsigned int offset; /* offset from the beginning of the table */
        
unsigned int size;
};

/* i2c child */

struct i2c_child_t {
	/* Either ADC or GPIO. */
	
unsigned char i2ctype;
        
unsigned long addr;    
        
struct pcf8584_channel chnl_array[PCF8584_MAX_CHANNELS];

	/* Channel info. */ 
	
unsigned int total_chnls;	/* Number of monitor channels. */
	
unsigned char fan_mask;		/* Byte mask for fan status channels. */
	
unsigned char voltage_mask;	/* Byte mask for voltage status channels. */
        
struct pcf8584_tblprop tblprop_array[PCF8584_MAX_CHANNELS];

	/* Properties of all monitor channels. */
	
unsigned int total_tbls;	/* Number of monitor tables. */
        
char *tables;			/* Pointer to table(s). */
	
char chnls_desc[CHANNEL_DESC_SZ]; /* Channel description. */
	
char mon_type[PCF8584_MAX_CHANNELS];
};


static void __iomem *i2c;

static struct i2c_child_t i2c_childlist[ENVCTRL_MAX_CPU*2];

static unsigned char chnls_mask[] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80 };

static unsigned int warning_temperature = 0;

static unsigned int shutdown_temperature = 0;

static char read_cpu;

/* Forward declarations. */
static struct i2c_child_t *envctrl_get_i2c_child(unsigned char);

/* Function Description: Test the PIN bit (Pending Interrupt Not) 
 *                       to test when serial transmission is completed .
 * Return : None.
 */

static void envtrl_i2c_test_pin(void) { int limit = 1000000; while (--limit > 0) { if (!(readb(i2c + PCF8584_CSR) & STATUS_PIN)) break; udelay(1); } if (limit <= 0) printk(KERN_INFO PFX "Pin status will not clear.\n"); }

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/* Function Description: Test busy bit. * Return : None. */
static void envctrl_i2c_test_bb(void) { int limit = 1000000; while (--limit > 0) { /* Busy bit 0 means busy. */ if (readb(i2c + PCF8584_CSR) & STATUS_BB) break; udelay(1); } if (limit <= 0) printk(KERN_INFO PFX "Busy bit will not clear.\n"); }

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/* Function Description: Send the address for a read access. * Return : 0 if not acknowledged, otherwise acknowledged. */
static int envctrl_i2c_read_addr(unsigned char addr) { envctrl_i2c_test_bb(); /* Load address. */ writeb(addr + 1, i2c + PCF8584_DATA); envctrl_i2c_test_bb(); writeb(OBD_SEND_START, i2c + PCF8584_CSR); /* Wait for PIN. */ envtrl_i2c_test_pin(); /* CSR 0 means acknowledged. */ if (!(readb(i2c + PCF8584_CSR) & STATUS_LRB)) { return readb(i2c + PCF8584_DATA); } else { writeb(OBD_SEND_STOP, i2c + PCF8584_CSR); return 0; } }

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/* Function Description: Send the address for write mode. * Return : None. */
static void envctrl_i2c_write_addr(unsigned char addr) { envctrl_i2c_test_bb(); writeb(addr, i2c + PCF8584_DATA); /* Generate Start condition. */ writeb(OBD_SEND_START, i2c + PCF8584_CSR); }

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/* Function Description: Read 1 byte of data from addr * set by envctrl_i2c_read_addr() * Return : Data from address set by envctrl_i2c_read_addr(). */
static unsigned char envctrl_i2c_read_data(void) { envtrl_i2c_test_pin(); writeb(CONTROL_ES0, i2c + PCF8584_CSR); /* Send neg ack. */ return readb(i2c + PCF8584_DATA); }

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/* Function Description: Instruct the device which port to read data from. * Return : None. */
static void envctrl_i2c_write_data(unsigned char port) { envtrl_i2c_test_pin(); writeb(port, i2c + PCF8584_DATA); }

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/* Function Description: Generate Stop condition after last byte is sent. * Return : None. */
static void envctrl_i2c_stop(void) { envtrl_i2c_test_pin(); writeb(OBD_SEND_STOP, i2c + PCF8584_CSR); }

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/* Function Description: Read adc device. * Return : Data at address and port. */
static unsigned char envctrl_i2c_read_8591(unsigned char addr, unsigned char port) { /* Send address. */ envctrl_i2c_write_addr(addr); /* Setup port to read. */ envctrl_i2c_write_data(port); envctrl_i2c_stop(); /* Read port. */ envctrl_i2c_read_addr(addr); /* Do a single byte read and send stop. */ envctrl_i2c_read_data(); envctrl_i2c_stop(); return readb(i2c + PCF8584_DATA); }

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/* Function Description: Read gpio device. * Return : Data at address. */
static unsigned char envctrl_i2c_read_8574(unsigned char addr) { unsigned char rd; envctrl_i2c_read_addr(addr); /* Do a single byte read and send stop. */ rd = envctrl_i2c_read_data(); envctrl_i2c_stop(); return rd; }

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/* Function Description: Decode data read from an adc device using firmware * table. * Return: Number of read bytes. Data is stored in bufdata in ascii format. */
static int envctrl_i2c_data_translate(unsigned char data, int translate_type, int scale, char *tbl, char *bufdata) { int len = 0; switch (translate_type) { case ENVCTRL_TRANSLATE_NO: /* No decode necessary. */ len = 1; bufdata[0] = data; break; case ENVCTRL_TRANSLATE_FULL: /* Decode this way: data = table[data]. */ len = 1; bufdata[0] = tbl[data]; break; case ENVCTRL_TRANSLATE_SCALE: /* Decode this way: data = table[data]/scale */ sprintf(bufdata,"%d ", (tbl[data] * 10) / (scale)); len = strlen(bufdata); bufdata[len - 1] = bufdata[len - 2]; bufdata[len - 2] = '.'; break; default: break; } return len; }

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/* Function Description: Read cpu-related data such as cpu temperature, voltage. * Return: Number of read bytes. Data is stored in bufdata in ascii format. */
static int envctrl_read_cpu_info(int cpu, struct i2c_child_t *pchild, char mon_type, unsigned char *bufdata) { unsigned char data; int i; char *tbl, j = -1; /* Find the right monitor type and channel. */ for (i = 0; i < PCF8584_MAX_CHANNELS; i++) { if (pchild->mon_type[i] == mon_type) { if (++j == cpu) { break; } } } if (j != cpu) return 0; /* Read data from address and port. */ data = envctrl_i2c_read_8591((unsigned char)pchild->addr, (unsigned char)pchild->chnl_array[i].chnl_no); /* Find decoding table. */ tbl = pchild->tables + pchild->tblprop_array[i].offset; return envctrl_i2c_data_translate(data, pchild->tblprop_array[i].type, pchild->tblprop_array[i].scale, tbl, bufdata); }

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/* Function Description: Read noncpu-related data such as motherboard * temperature. * Return: Number of read bytes. Data is stored in bufdata in ascii format. */
static int envctrl_read_noncpu_info(struct i2c_child_t *pchild, char mon_type, unsigned char *bufdata) { unsigned char data; int i; char *tbl = NULL; for (i = 0; i < PCF8584_MAX_CHANNELS; i++) { if (pchild->mon_type[i] == mon_type) break; } if (i >= PCF8584_MAX_CHANNELS) return 0; /* Read data from address and port. */ data = envctrl_i2c_read_8591((unsigned char)pchild->addr, (unsigned char)pchild->chnl_array[i].chnl_no); /* Find decoding table. */ tbl = pchild->tables + pchild->tblprop_array[i].offset; return envctrl_i2c_data_translate(data, pchild->tblprop_array[i].type, pchild->tblprop_array[i].scale, tbl, bufdata); }

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/* Function Description: Read fan status. * Return : Always 1 byte. Status stored in bufdata. */
static int envctrl_i2c_fan_status(struct i2c_child_t *pchild, unsigned char data, char *bufdata) { unsigned char tmp, ret = 0; int i, j = 0; tmp = data & pchild->fan_mask; if (tmp == pchild->fan_mask) { /* All bits are on. All fans are functioning. */ ret = ENVCTRL_ALL_FANS_GOOD; } else if (tmp == 0) { /* No bits are on. No fans are functioning. */ ret = ENVCTRL_ALL_FANS_BAD; } else { /* Go through all channels, mark 'on' the matched bits. * Notice that fan_mask may have discontiguous bits but * return mask are always contiguous. For example if we * monitor 4 fans at channels 0,1,2,4, the return mask * should be 00010000 if only fan at channel 4 is working. */ for (i = 0; i < PCF8584_MAX_CHANNELS;i++) { if (pchild->fan_mask & chnls_mask[i]) { if (!(chnls_mask[i] & tmp)) ret |= chnls_mask[j]; j++; } } } bufdata[0] = ret; return 1; }

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/* Function Description: Read global addressing line. * Return : Always 1 byte. Status stored in bufdata. */
static int envctrl_i2c_globaladdr(struct i2c_child_t *pchild, unsigned char data, char *bufdata) { /* Translatation table is not necessary, as global * addr is the integer value of the GA# bits. * * NOTE: MSB is documented as zero, but I see it as '1' always.... * * ----------------------------------------------- * | 0 | FAL | DEG | GA4 | GA3 | GA2 | GA1 | GA0 | * ----------------------------------------------- * GA0 - GA4 integer value of Global Address (backplane slot#) * DEG 0 = cPCI Power supply output is starting to degrade * 1 = cPCI Power supply output is OK * FAL 0 = cPCI Power supply has failed * 1 = cPCI Power supply output is OK */ bufdata[0] = (data & ENVCTRL_GLOBALADDR_ADDR_MASK); return 1; }

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/* Function Description: Read standard voltage and power supply status. * Return : Always 1 byte. Status stored in bufdata. */
static unsigned char envctrl_i2c_voltage_status(struct i2c_child_t *pchild, unsigned char data, char *bufdata) { unsigned char tmp, ret = 0; int i, j = 0; tmp = data & pchild->voltage_mask; /* Two channels are used to monitor voltage and power supply. */ if (tmp == pchild->voltage_mask) { /* All bits are on. Voltage and power supply are okay. */ ret = ENVCTRL_VOLTAGE_POWERSUPPLY_GOOD; } else if (tmp == 0) { /* All bits are off. Voltage and power supply are bad */ ret = ENVCTRL_VOLTAGE_POWERSUPPLY_BAD; } else { /* Either voltage or power supply has problem. */ for (i = 0; i < PCF8584_MAX_CHANNELS; i++) { if (pchild->voltage_mask & chnls_mask[i]) { j++; /* Break out when there is a mismatch. */ if (!(chnls_mask[i] & tmp)) break; } } /* Make a wish that hardware will always use the * first channel for voltage and the second for * power supply. */ if (j == 1) ret = ENVCTRL_VOLTAGE_BAD; else ret = ENVCTRL_POWERSUPPLY_BAD; } bufdata[0] = ret; return 1; }

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/* Function Description: Read a byte from /dev/envctrl. Mapped to user read(). * Return: Number of read bytes. 0 for error. */
static ssize_t envctrl_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) { struct i2c_child_t *pchild; unsigned char data[10]; int ret = 0; /* Get the type of read as decided in ioctl() call. * Find the appropriate i2c child. * Get the data and put back to the user buffer. */ switch ((int)(long)file->private_data) { case ENVCTRL_RD_WARNING_TEMPERATURE: if (warning_temperature == 0) return 0; data[0] = (unsigned char)(warning_temperature); ret = 1; if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_SHUTDOWN_TEMPERATURE: if (shutdown_temperature == 0) return 0; data[0] = (unsigned char)(shutdown_temperature); ret = 1; if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_MTHRBD_TEMPERATURE: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_MTHRBDTEMP_MON))) return 0; ret = envctrl_read_noncpu_info(pchild, ENVCTRL_MTHRBDTEMP_MON, data); if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_CPU_TEMPERATURE: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_CPUTEMP_MON))) return 0; ret = envctrl_read_cpu_info(read_cpu, pchild, ENVCTRL_CPUTEMP_MON, data); /* Reset cpu to the default cpu0. */ if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_CPU_VOLTAGE: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_CPUVOLTAGE_MON))) return 0; ret = envctrl_read_cpu_info(read_cpu, pchild, ENVCTRL_CPUVOLTAGE_MON, data); /* Reset cpu to the default cpu0. */ if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_SCSI_TEMPERATURE: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_SCSITEMP_MON))) return 0; ret = envctrl_read_noncpu_info(pchild, ENVCTRL_SCSITEMP_MON, data); if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_ETHERNET_TEMPERATURE: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_ETHERTEMP_MON))) return 0; ret = envctrl_read_noncpu_info(pchild, ENVCTRL_ETHERTEMP_MON, data); if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_FAN_STATUS: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_FANSTAT_MON))) return 0; data[0] = envctrl_i2c_read_8574(pchild->addr); ret = envctrl_i2c_fan_status(pchild,data[0], data); if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_GLOBALADDRESS: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_GLOBALADDR_MON))) return 0; data[0] = envctrl_i2c_read_8574(pchild->addr); ret = envctrl_i2c_globaladdr(pchild, data[0], data); if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; case ENVCTRL_RD_VOLTAGE_STATUS: if (!(pchild = envctrl_get_i2c_child(ENVCTRL_VOLTAGESTAT_MON))) /* If voltage monitor not present, check for CPCI equivalent */ if (!(pchild = envctrl_get_i2c_child(ENVCTRL_GLOBALADDR_MON))) return 0; data[0] = envctrl_i2c_read_8574(pchild->addr); ret = envctrl_i2c_voltage_status(pchild, data[0], data); if (copy_to_user(buf, data, ret)) ret = -EFAULT; break; default: break; } return ret; }

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/* Function Description: Command what to read. Mapped to user ioctl(). * Return: Gives 0 for implemented commands, -EINVAL otherwise. */
static long envctrl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { char __user *infobuf; switch (cmd) { case ENVCTRL_RD_WARNING_TEMPERATURE: case ENVCTRL_RD_SHUTDOWN_TEMPERATURE: case ENVCTRL_RD_MTHRBD_TEMPERATURE: case ENVCTRL_RD_FAN_STATUS: case ENVCTRL_RD_VOLTAGE_STATUS: case ENVCTRL_RD_ETHERNET_TEMPERATURE: case ENVCTRL_RD_SCSI_TEMPERATURE: case ENVCTRL_RD_GLOBALADDRESS: file->private_data = (void *)(long)cmd; break; case ENVCTRL_RD_CPU_TEMPERATURE: case ENVCTRL_RD_CPU_VOLTAGE: /* Check to see if application passes in any cpu number, * the default is cpu0. */ infobuf = (char __user *) arg; if (infobuf == NULL) { read_cpu = 0; }else { get_user(read_cpu, infobuf); } /* Save the command for use when reading. */ file->private_data = (void *)(long)cmd; break; default: return -EINVAL; } return 0; }

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/* Function Description: open device. Mapped to user open(). * Return: Always 0. */
static int envctrl_open(struct inode *inode, struct file *file) { file->private_data = NULL; return 0; }

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/* Function Description: Open device. Mapped to user close(). * Return: Always 0. */
static int envctrl_release(struct inode *inode, struct