diff options
Diffstat (limited to 'arch/cris/arch-v10/drivers/eeprom.c')
| -rw-r--r-- | arch/cris/arch-v10/drivers/eeprom.c | 852 |
1 files changed, 0 insertions, 852 deletions
diff --git a/arch/cris/arch-v10/drivers/eeprom.c b/arch/cris/arch-v10/drivers/eeprom.c deleted file mode 100644 index 2d312c8a4dd5..000000000000 --- a/arch/cris/arch-v10/drivers/eeprom.c +++ /dev/null @@ -1,852 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/*!***************************************************************************** -*! -*! Implements an interface for i2c compatible eeproms to run under Linux. -*! Supports 2k, 8k(?) and 16k. Uses adaptive timing adjustments by -*! Johan.Adolfsson@axis.com -*! -*! Probing results: -*! 8k or not is detected (the assumes 2k or 16k) -*! 2k or 16k detected using test reads and writes. -*! -*!------------------------------------------------------------------------ -*! HISTORY -*! -*! DATE NAME CHANGES -*! ---- ---- ------- -*! Aug 28 1999 Edgar Iglesias Initial Version -*! Aug 31 1999 Edgar Iglesias Allow simultaneous users. -*! Sep 03 1999 Edgar Iglesias Updated probe. -*! Sep 03 1999 Edgar Iglesias Added bail-out stuff if we get interrupted -*! in the spin-lock. -*! -*! (c) 1999 Axis Communications AB, Lund, Sweden -*!*****************************************************************************/ - -#include <linux/kernel.h> -#include <linux/sched.h> -#include <linux/fs.h> -#include <linux/init.h> -#include <linux/delay.h> -#include <linux/interrupt.h> -#include <linux/wait.h> -#include <linux/uaccess.h> -#include "i2c.h" - -#define D(x) - -/* If we should use adaptive timing or not: */ -/* #define EEPROM_ADAPTIVE_TIMING */ - -#define EEPROM_MAJOR_NR 122 /* use a LOCAL/EXPERIMENTAL major for now */ -#define EEPROM_MINOR_NR 0 - -/* Empirical sane initial value of the delay, the value will be adapted to - * what the chip needs when using EEPROM_ADAPTIVE_TIMING. - */ -#define INITIAL_WRITEDELAY_US 4000 -#define MAX_WRITEDELAY_US 10000 /* 10 ms according to spec for 2KB EEPROM */ - -/* This one defines how many times to try when eeprom fails. */ -#define EEPROM_RETRIES 10 - -#define EEPROM_2KB (2 * 1024) -/*#define EEPROM_4KB (4 * 1024)*/ /* Exists but not used in Axis products */ -#define EEPROM_8KB (8 * 1024 - 1 ) /* Last byte has write protection bit */ -#define EEPROM_16KB (16 * 1024) - -#define i2c_delay(x) udelay(x) - -/* - * This structure describes the attached eeprom chip. - * The values are probed for. - */ - -struct eeprom_type -{ - unsigned long size; - unsigned long sequential_write_pagesize; - unsigned char select_cmd; - unsigned long usec_delay_writecycles; /* Min time between write cycles - (up to 10ms for some models) */ - unsigned long usec_delay_step; /* For adaptive algorithm */ - int adapt_state; /* 1 = To high , 0 = Even, -1 = To low */ - - /* this one is to keep the read/write operations atomic */ - struct mutex lock; - int retry_cnt_addr; /* Used to keep track of number of retries for - adaptive timing adjustments */ - int retry_cnt_read; -}; - -static int eeprom_open(struct inode * inode, struct file * file); -static loff_t eeprom_lseek(struct file * file, loff_t offset, int orig); -static ssize_t eeprom_read(struct file * file, char * buf, size_t count, - loff_t *off); -static ssize_t eeprom_write(struct file * file, const char * buf, size_t count, - loff_t *off); -static int eeprom_close(struct inode * inode, struct file * file); - -static int eeprom_address(unsigned long addr); -static int read_from_eeprom(char * buf, int count); -static int eeprom_write_buf(loff_t addr, const char * buf, int count); -static int eeprom_read_buf(loff_t addr, char * buf, int count); - -static void eeprom_disable_write_protect(void); - - -static const char eeprom_name[] = "eeprom"; - -/* chip description */ -static struct eeprom_type eeprom; - -/* This is the exported file-operations structure for this device. */ -const struct file_operations eeprom_fops = -{ - .llseek = eeprom_lseek, - .read = eeprom_read, - .write = eeprom_write, - .open = eeprom_open, - .release = eeprom_close -}; - -/* eeprom init call. Probes for different eeprom models. */ - -int __init eeprom_init(void) -{ - mutex_init(&eeprom.lock); - -#ifdef CONFIG_ETRAX_I2C_EEPROM_PROBE -#define EETEXT "Found" -#else -#define EETEXT "Assuming" -#endif - if (register_chrdev(EEPROM_MAJOR_NR, eeprom_name, &eeprom_fops)) - { - printk(KERN_INFO "%s: unable to get major %d for eeprom device\n", - eeprom_name, EEPROM_MAJOR_NR); - return -1; - } - - printk("EEPROM char device v0.3, (c) 2000 Axis Communications AB\n"); - - /* - * Note: Most of this probing method was taken from the printserver (5470e) - * codebase. It did not contain a way of finding the 16kB chips - * (M24128 or variants). The method used here might not work - * for all models. If you encounter problems the easiest way - * is probably to define your model within #ifdef's, and hard- - * code it. - */ - - eeprom.size = 0; - eeprom.usec_delay_writecycles = INITIAL_WRITEDELAY_US; - eeprom.usec_delay_step = 128; - eeprom.adapt_state = 0; - -#ifdef CONFIG_ETRAX_I2C_EEPROM_PROBE - i2c_start(); - i2c_outbyte(0x80); - if(!i2c_getack()) - { - /* It's not 8k.. */ - int success = 0; - unsigned char buf_2k_start[16]; - - /* Im not sure this will work... :) */ - /* assume 2kB, if failure go for 16kB */ - /* Test with 16kB settings.. */ - /* If it's a 2kB EEPROM and we address it outside it's range - * it will mirror the address space: - * 1. We read two locations (that are mirrored), - * if the content differs * it's a 16kB EEPROM. - * 2. if it doesn't differ - write different value to one of the locations, - * check the other - if content still is the same it's a 2k EEPROM, - * restore original data. - */ -#define LOC1 8 -#define LOC2 (0x1fb) /*1fb, 3ed, 5df, 7d1 */ - - /* 2k settings */ - i2c_stop(); - eeprom.size = EEPROM_2KB; - eeprom.select_cmd = 0xA0; - eeprom.sequential_write_pagesize = 16; - if( eeprom_read_buf( 0, buf_2k_start, 16 ) == 16 ) - { - D(printk("2k start: '%16.16s'\n", buf_2k_start)); - } - else - { - printk(KERN_INFO "%s: Failed to read in 2k mode!\n", eeprom_name); - } - - /* 16k settings */ - eeprom.size = EEPROM_16KB; - eeprom.select_cmd = 0xA0; - eeprom.sequential_write_pagesize = 64; - - { - unsigned char loc1[4], loc2[4], tmp[4]; - if( eeprom_read_buf(LOC2, loc2, 4) == 4) - { - if( eeprom_read_buf(LOC1, loc1, 4) == 4) - { - D(printk("0 loc1: (%i) '%4.4s' loc2 (%i) '%4.4s'\n", - LOC1, loc1, LOC2, loc2)); -#if 0 - if (memcmp(loc1, loc2, 4) != 0 ) - { - /* It's 16k */ - printk(KERN_INFO "%s: 16k detected in step 1\n", eeprom_name); - eeprom.size = EEPROM_16KB; - success = 1; - } - else -#endif - { - /* Do step 2 check */ - /* Invert value */ - loc1[0] = ~loc1[0]; - if (eeprom_write_buf(LOC1, loc1, 1) == 1) - { - /* If 2k EEPROM this write will actually write 10 bytes - * from pos 0 - */ - D(printk("1 loc1: (%i) '%4.4s' loc2 (%i) '%4.4s'\n", - LOC1, loc1, LOC2, loc2)); - if( eeprom_read_buf(LOC1, tmp, 4) == 4) - { - D(printk("2 loc1: (%i) '%4.4s' tmp '%4.4s'\n", - LOC1, loc1, tmp)); - if (memcmp(loc1, tmp, 4) != 0 ) - { - printk(KERN_INFO "%s: read and write differs! Not 16kB\n", - eeprom_name); - loc1[0] = ~loc1[0]; - - if (eeprom_write_buf(LOC1, loc1, 1) == 1) - { - success = 1; - } - else - { - printk(KERN_INFO "%s: Restore 2k failed during probe," - " EEPROM might be corrupt!\n", eeprom_name); - - } - i2c_stop(); - /* Go to 2k mode and write original data */ - eeprom.size = EEPROM_2KB; - eeprom.select_cmd = 0xA0; - eeprom.sequential_write_pagesize = 16; - if( eeprom_write_buf(0, buf_2k_start, 16) == 16) - { - } - else - { - printk(KERN_INFO "%s: Failed to write back 2k start!\n", - eeprom_name); - } - - eeprom.size = EEPROM_2KB; - } - } - - if(!success) - { - if( eeprom_read_buf(LOC2, loc2, 1) == 1) - { - D(printk("0 loc1: (%i) '%4.4s' loc2 (%i) '%4.4s'\n", - LOC1, loc1, LOC2, loc2)); - if (memcmp(loc1, loc2, 4) == 0 ) - { - /* Data the same, must be mirrored -> 2k */ - /* Restore data */ - printk(KERN_INFO "%s: 2k detected in step 2\n", eeprom_name); - loc1[0] = ~loc1[0]; - if (eeprom_write_buf(LOC1, loc1, 1) == 1) - { - success = 1; - } - else - { - printk(KERN_INFO "%s: Restore 2k failed during probe," - " EEPROM might be corrupt!\n", eeprom_name); - - } - - eeprom.size = EEPROM_2KB; - } - else - { - printk(KERN_INFO "%s: 16k detected in step 2\n", - eeprom_name); - loc1[0] = ~loc1[0]; - /* Data differs, assume 16k */ - /* Restore data */ - if (eeprom_write_buf(LOC1, loc1, 1) == 1) - { - success = 1; - } - else - { - printk(KERN_INFO "%s: Restore 16k failed during probe," - " EEPROM might be corrupt!\n", eeprom_name); - } - - eeprom.size = EEPROM_16KB; - } - } - } - } - } /* read LOC1 */ - } /* address LOC1 */ - if (!success) - { - printk(KERN_INFO "%s: Probing failed!, using 2KB!\n", eeprom_name); - eeprom.size = EEPROM_2KB; - } - } /* read */ - } - } - else - { - i2c_outbyte(0x00); - if(!i2c_getack()) - { - /* No 8k */ - eeprom.size = EEPROM_2KB; - } - else - { - i2c_start(); - i2c_outbyte(0x81); - if (!i2c_getack()) - { - eeprom.size = EEPROM_2KB; - } - else - { - /* It's a 8kB */ - i2c_inbyte(); - eeprom.size = EEPROM_8KB; - } - } - } - i2c_stop(); -#elif defined(CONFIG_ETRAX_I2C_EEPROM_16KB) - eeprom.size = EEPROM_16KB; -#elif defined(CONFIG_ETRAX_I2C_EEPROM_8KB) - eeprom.size = EEPROM_8KB; -#elif defined(CONFIG_ETRAX_I2C_EEPROM_2KB) - eeprom.size = EEPROM_2KB; -#endif - - switch(eeprom.size) - { - case (EEPROM_2KB): - printk("%s: " EETEXT " i2c compatible 2kB eeprom.\n", eeprom_name); - eeprom.sequential_write_pagesize = 16; - eeprom.select_cmd = 0xA0; - break; - case (EEPROM_8KB): - printk("%s: " EETEXT " i2c compatible 8kB eeprom.\n", eeprom_name); - eeprom.sequential_write_pagesize = 16; - eeprom.select_cmd = 0x80; - break; - case (EEPROM_16KB): - printk("%s: " EETEXT " i2c compatible 16kB eeprom.\n", eeprom_name); - eeprom.sequential_write_pagesize = 64; - eeprom.select_cmd = 0xA0; - break; - default: - eeprom.size = 0; - printk("%s: Did not find a supported eeprom\n", eeprom_name); - break; - } - - - - eeprom_disable_write_protect(); - - return 0; -} - -/* Opens the device. */ -static int eeprom_open(struct inode * inode, struct file * file) -{ - if(iminor(inode) != EEPROM_MINOR_NR) - return -ENXIO; - if(imajor(inode) != EEPROM_MAJOR_NR) - return -ENXIO; - - if( eeprom.size > 0 ) - { - /* OK */ - return 0; - } - - /* No EEprom found */ - return -EFAULT; -} - -/* Changes the current file position. */ - -static loff_t eeprom_lseek(struct file * file, loff_t offset, int orig) -{ -/* - * orig 0: position from beginning of eeprom - * orig 1: relative from current position - * orig 2: position from last eeprom address - */ - - switch (orig) - { - case 0: - file->f_pos = offset; - break; - case 1: - file->f_pos += offset; - break; - case 2: - file->f_pos = eeprom.size - offset; - break; - default: - return -EINVAL; - } - - /* truncate position */ - if (file->f_pos < 0) - { - file->f_pos = 0; - return(-EOVERFLOW); - } - - if (file->f_pos >= eeprom.size) - { - file->f_pos = eeprom.size - 1; - return(-EOVERFLOW); - } - - return ( file->f_pos ); -} - -/* Reads data from eeprom. */ - -static int eeprom_read_buf(loff_t addr, char * buf, int count) -{ - return eeprom_read(NULL, buf, count, &addr); -} - - - -/* Reads data from eeprom. */ - -static ssize_t eeprom_read(struct file * file, char * buf, size_t count, loff_t *off) -{ - int read=0; - unsigned long p = *off; - - unsigned char page; - - if(p >= eeprom.size) /* Address i 0 - (size-1) */ - { - return -EFAULT; - } - - if (mutex_lock_interruptible(&eeprom.lock)) - return -EINTR; - - page = (unsigned char) (p >> 8); - - if(!eeprom_address(p)) - { - printk(KERN_INFO "%s: Read failed to address the eeprom: " - "0x%08X (%i) page: %i\n", eeprom_name, (int)p, (int)p, page); - i2c_stop(); - - /* don't forget to wake them up */ - mutex_unlock(&eeprom.lock); - return -EFAULT; - } - - if( (p + count) > eeprom.size) - { - /* truncate count */ - count = eeprom.size - p; - } - - /* stop dummy write op and initiate the read op */ - i2c_start(); - - /* special case for small eeproms */ - if(eeprom.size < EEPROM_16KB) - { - i2c_outbyte( eeprom.select_cmd | 1 | (page << 1) ); - } - - /* go on with the actual read */ - read = read_from_eeprom( buf, count); - - if(read > 0) - { - *off += read; - } - - mutex_unlock(&eeprom.lock); - return read; -} - -/* Writes data to eeprom. */ - -static int eeprom_write_buf(loff_t addr, const char * buf, int count) -{ - return eeprom_write(NULL, buf, count, &addr); -} - - -/* Writes data to eeprom. */ - -static ssize_t eeprom_write(struct file * file, const char * buf, size_t count, - loff_t *off) -{ - int i, written, restart=1; - unsigned long p; - - if (!access_ok(VERIFY_READ, buf, count)) - { - return -EFAULT; - } - - /* bail out if we get interrupted */ - if (mutex_lock_interruptible(&eeprom.lock)) - return -EINTR; - for(i = 0; (i < EEPROM_RETRIES) && (restart > 0); i++) - { - restart = 0; - written = 0; - p = *off; - - - while( (written < count) && (p < eeprom.size)) - { - /* address the eeprom */ - if(!eeprom_address(p)) - { - printk(KERN_INFO "%s: Write failed to address the eeprom: " - "0x%08X (%i) \n", eeprom_name, (int)p, (int)p); - i2c_stop(); - - /* don't forget to wake them up */ - mutex_unlock(&eeprom.lock); - return -EFAULT; - } -#ifdef EEPROM_ADAPTIVE_TIMING - /* Adaptive algorithm to adjust timing */ - if (eeprom.retry_cnt_addr > 0) - { - /* To Low now */ - D(printk(">D=%i d=%i\n", - eeprom.usec_delay_writecycles, eeprom.usec_delay_step)); - - if (eeprom.usec_delay_step < 4) - { - eeprom.usec_delay_step++; - eeprom.usec_delay_writecycles += eeprom.usec_delay_step; - } - else - { - - if (eeprom.adapt_state > 0) - { - /* To Low before */ - eeprom.usec_delay_step *= 2; - if (eeprom.usec_delay_step > 2) - { - eeprom.usec_delay_step--; - } - eeprom.usec_delay_writecycles += eeprom.usec_delay_step; - } - else if (eeprom.adapt_state < 0) - { - /* To High before (toggle dir) */ - eeprom.usec_delay_writecycles += eeprom.usec_delay_step; - if (eeprom.usec_delay_step > 1) - { - eeprom.usec_delay_step /= 2; - eeprom.usec_delay_step--; - } - } - } - - eeprom.adapt_state = 1; - } - else - { - /* To High (or good) now */ - D(printk("<D=%i d=%i\n", - eeprom.usec_delay_writecycles, eeprom.usec_delay_step)); - - if (eeprom.adapt_state < 0) - { - /* To High before */ - if (eeprom.usec_delay_step > 1) - { - eeprom.usec_delay_step *= 2; - eeprom.usec_delay_step--; - - if (eeprom.usec_delay_writecycles > eeprom.usec_delay_step) - { - eeprom.usec_delay_writecycles -= eeprom.usec_delay_step; - } - } - } - else if (eeprom.adapt_state > 0) - { - /* To Low before (toggle dir) */ - if (eeprom.usec_delay_writecycles > eeprom.usec_delay_step) - { - eeprom.usec_delay_writecycles -= eeprom.usec_delay_step; - } - if (eeprom.usec_delay_step > 1) - { - eeprom.usec_delay_step /= 2; - eeprom.usec_delay_step--; - } - - eeprom.adapt_state = -1; - } - - if (eeprom.adapt_state > -100) - { - eeprom.adapt_state--; - } - else - { - /* Restart adaption */ - D(printk("#Restart\n")); - eeprom.usec_delay_step++; - } - } -#endif /* EEPROM_ADAPTIVE_TIMING */ - /* write until we hit a page boundary or count */ - do - { - i2c_outbyte(buf[written]); - if(!i2c_getack()) - { - restart=1; - printk(KERN_INFO "%s: write error, retrying. %d\n", eeprom_name, i); - i2c_stop(); - break; - } - written++; - p++; - } while( written < count && ( p % eeprom.sequential_write_pagesize )); - - /* end write cycle */ - i2c_stop(); - i2c_delay(eeprom.usec_delay_writecycles); - } /* while */ - } /* for */ - - mutex_unlock(&eeprom.lock); - if (written == 0 && p >= eeprom.size){ - return -ENOSPC; - } - *off = p; - return written; -} - -/* Closes the device. */ - -static int eeprom_close(struct inode * inode, struct file * file) -{ - /* do nothing for now */ - return 0; -} - -/* Sets the current address of the eeprom. */ - -static int eeprom_address(unsigned long addr) -{ - int i; - unsigned char page, offset; - - page = (unsigned char) (addr >> 8); - offset = (unsigned char) addr; - - for(i = 0; i < EEPROM_RETRIES; i++) - { - /* start a dummy write for addressing */ - i2c_start(); - - if(eeprom.size == EEPROM_16KB) - { - i2c_outbyte( eeprom.select_cmd ); - i2c_getack(); - i2c_outbyte(page); - } - else - { - i2c_outbyte( eeprom.select_cmd | (page << 1) ); - } - if(!i2c_getack()) - { - /* retry */ - i2c_stop(); - /* Must have a delay here.. 500 works, >50, 100->works 5th time*/ - i2c_delay(MAX_WRITEDELAY_US / EEPROM_RETRIES * i); - /* The chip needs up to 10 ms from write stop to next start */ - - } - else - { - i2c_outbyte(offset); - - if(!i2c_getack()) - { - /* retry */ - i2c_stop(); - } - else - break; - } - } - - - eeprom.retry_cnt_addr = i; - D(printk("%i\n", eeprom.retry_cnt_addr)); - if(eeprom.retry_cnt_addr == EEPROM_RETRIES) - { - /* failed */ - return 0; - } - return 1; -} - -/* Reads from current address. */ - -static int read_from_eeprom(char * buf, int count) -{ - int i, read=0; - - for(i = 0; i < EEPROM_RETRIES; i++) - { - if(eeprom.size == EEPROM_16KB) - { - i2c_outbyte( eeprom.select_cmd | 1 ); - } - - if(i2c_getack()) - { - break; - } - } - - if(i == EEPROM_RETRIES) - { - printk(KERN_INFO "%s: failed to read from eeprom\n", eeprom_name); - i2c_stop(); - - return -EFAULT; - } - - while( (read < count)) - { - if (put_user(i2c_inbyte(), &buf[read++])) - { - i2c_stop(); - - return -EFAULT; - } - - /* - * make sure we don't ack last byte or you will get very strange - * results! - */ - if(read < count) - { - i2c_sendack(); - } - } - - /* stop the operation */ - i2c_stop(); - - return read; -} - -/* Disables write protection if applicable. */ - -#define DBP_SAVE(x) -#define ax_printf printk -static void eeprom_disable_write_protect(void) -{ - /* Disable write protect */ - if (eeprom.size == EEPROM_8KB) - { - /* Step 1 Set WEL = 1 (write 00000010 to address 1FFFh */ - i2c_start(); - i2c_outbyte(0xbe); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false\n")); - } - i2c_outbyte(0xFF); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 2\n")); - } - i2c_outbyte(0x02); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 3\n")); - } - i2c_stop(); - - i2c_delay(1000); - - /* Step 2 Set RWEL = 1 (write 00000110 to address 1FFFh */ - i2c_start(); - i2c_outbyte(0xbe); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 55\n")); - } - i2c_outbyte(0xFF); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 52\n")); - } - i2c_outbyte(0x06); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 53\n")); - } - i2c_stop(); - - /* Step 3 Set BP1, BP0, and/or WPEN bits (write 00000110 to address 1FFFh */ - i2c_start(); - i2c_outbyte(0xbe); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 56\n")); - } - i2c_outbyte(0xFF); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 57\n")); - } - i2c_outbyte(0x06); - if(!i2c_getack()) - { - DBP_SAVE(ax_printf("Get ack returns false 58\n")); - } - i2c_stop(); - - /* Write protect disabled */ - } -} -device_initcall(eeprom_init); |