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linux-stable/arch/cris/arch-v10/drivers/eeprom.c
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license 
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00

852 lines
22 KiB
C
Raw Blame History

// 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);
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