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<?php
/*!***************************************************************************
*! FILE NAME : i2c.inc
*! DESCRIPTION: Provides functions to read/write over i2c buses in the camera,
*! low-level R/W and additionally:
*! Setting per-slave protection mask,
*! Synchronizing system clock with a "CMOS" one
*! Reading from/writing to EEPROM memory
*! Copyright (C) 2008-2016 Elphel, Inc
*! -----------------------------------------------------------------------------**
*!
*! This program is free software: you can redistribute it and/or modify
*! it under the terms of the GNU General Public License as published by
*! the Free Software Foundation, either version 3 of the License, or
*! (at your option) any later version.
*!
*! This program is distributed in the hope that it will be useful,
*! but WITHOUT ANY WARRANTY; without even the implied warranty of
*! MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
*! GNU General Public License for more details.
*!
*! You should have received a copy of the GNU General Public License
*! along with this program. If not, see <http://www.gnu.org/licenses/>.
*! -----------------------------------------------------------------------------**
*! $Log: i2c.inc,v $
*! Revision 1.4 2012/01/12 19:09:28 elphel
*! bug fix
*!
*! Revision 1.3 2011/12/22 05:35:11 elphel
*! Added "slow" option (for slow i2c devices) and reading the sensor board temperature
*!
*! Revision 1.2 2010/08/10 21:11:40 elphel
*! added EEPROM support of the 10359 and 10338D boards.
*!
*! Revision 1.1.1.1 2008/11/27 20:04:03 elphel
*!
*!
*! Revision 1.3 2008/10/04 16:09:04 elphel
*! updating FPGA time with system time from CMOS
*!
*! Revision 1.2 2008/06/04 20:26:23 elphel
*! includes SMBus operations, needed to activate USB on the 10369A board
*!
*! Revision 1.2 2008/03/16 01:24:09 elphel
*! Added i2c speed control interface
*!
*! Revision 1.1 2008/03/15 23:05:18 elphel
*! split i2c.php into i2c.php and i2c.inc (to be used from other scripts)
*!
*!
*/
//$i2c_slow_safe=array(3,4,2,2,7,7); /// sensor i2c delays are 2,2,1,1,7,7
// In NC393: buses 0..3 - sensors(old bus=0), 4 - aux (old bus=1)
/// NC393-fucnctions to read/write sensor ports
/// Reusing NC53 parameters: $width->$name, $raw ->
function i2c_send_sensor($name, ///< device class name (get all by "cat /sys/devices/soc0/elphel393-sensor-i2c@0/i2c_all")
$sensor_port, ///< sensor port :0..3
$ra, ///< register address
$data, ///< data to write
$sa7_offset=0) ///< slave address offset when there are multiple devices (2*sub-channel in 10359)
///< return true on success, false on failure
{ //$a<0 - use raw read/write
$path = '/sys/devices/soc0/elphel393-sensor-i2c@0/i2c'.strval($sensor_port);
$rslt = file_put_contents ($path, $name.' ' . strval($sa7_offset) . ' ' . strval($ra) . ' ' . strval($data));
return $rslt;
}
function i2c_receive_sensor($name, ///< device class name (get all by "cat /sys/devices/soc0/elphel393-sensor-i2c@0/i2c_all")
$sensor_port, ///< sensor port :0..3
$ra, ///< register address
$sa7_offset=0) ///< slave address offset when there are multiple devices (2*sub-channel in 10359)
///< @return read data or -1 on error
{
// Initiate read
$path = '/sys/devices/soc0/elphel393-sensor-i2c@0/i2c'.strval($sensor_port);
$rslt = file_put_contents ($path, $name.' ' . strval($sa7_offset) . ' ' . strval($ra) );
if (!$rslt)
return -1;
$rslt = file_get_contents ($path);
if ($rslt === false)
return -1;
return intval($rslt);
}
/** Read 256 bytes from device as a string */
function i2c_read256b_sensor($name, ///< device class name (get all by "cat /sys/devices/soc0/elphel393-sensor-i2c@0/i2c_all")
$sensor_port, ///< sensor port :0..3
$sa7_offset=0) ///< slave address offset when there are multiple devices (2*sub-channel in 10359)
///< @return read data string or partial (empty) string on error
{
$rslt = '';
for ($ra=0;$ra<256;$ra++){
if (($d = i2c_receive_sensor($name,$sensor_port,$ra,$sa7_offset))<0) break;
$rslt .= chr($d);
}
return $rslt;
}
/** Write string to device */
function i2c_write256b_sensor($data, ///< Sring to write
$name, ///< device class name (get all by "cat /sys/devices/soc0/elphel393-sensor-i2c@0/i2c_all")
$sensor_port, ///< sensor port :0..3
$sa7_offset=0) ///< slave address offset when there are multiple devices (2*sub-channel in 10359)
///< @return number of bytes written
{
$len = 0;
if (strlen($data)<256) $data.=chr(0);
for ($ra=0;$ra<strlen($data);$ra++){
$b = ord(substr($data,$ra,1));
if (($d = i2c_send_sensor($name,$sensor_port,$ra,$b,$sa7_offset))<0) break;
usleep(10000);
$len ++;
}
return $len;
}
///sys/devices/soc0/elphel393-sensor-i2c@0# echo "mt9p006 8 9" > i2c3; cat i2c3
/*
cy22393: 0x69 1 1 100 kHz
sensor_temp: 0x18 1 2 100 kHz
sensor_eeprom: 0x50 1 1 100 kHz
pca9500_eeprom: 0x50 1 1 100 kHz
el10359_32: 0x8 1 4 500 kHz
el10359: 0x8 1 2 500 kHz
mt9p006: 0x48 1 2 500 kHz
mt9f002: 0x10 2 2 500 kHz
*/
/** Convert nc353 addres/width to sa7 and register address */
function aw_to_sa7r($adr, ///< composite address, nc353 style (256 bytes for each byte-wide device, 512 bytes for each 16-bit one)
$width ///< Data with 16 or 8
) ///< @return: array(sa7,ra)
{
$sa7 = ($adr >> (($width == 16) ? 9 : 8)) & 0x7f;
$ra = ($adr >> (($width == 16) ? 1 : 0)) & 0xff;
return array(sa7,ra);
}
function getSlowArray($usec=0){
if ($usec<0) $usec=0;
$SCL_low=3+(int) ($usec*8);
$SCL_high=4+(int) ($usec*8);
if ($SCL_low>254) $SCL_low=254;
if ($SCL_high>254) $SCL_high=254;
$i2c_slow_safe=array($SCL_low ,$SCL_high,2,2,7,7); /// sensor i2c delays are 2,2,1,1,7,7
return $i2c_slow_safe;
}
///Map i2c bus of 393 to "old" one
function i2c_bus353($bus){
if ($bus<4) return 0;
else return $bus-3;
}
function i2c_ctl($bus,$data="") { //!$data - string of decimal values separated by ":", empty - don't change
$size=6; // bytes per bus
$data=trim($data);
if ($data!="") {
$darr=explode(":",$data);
$i2cctl = fopen('/dev/xi2cctl', 'w');
for ($i=0; ($i<$size) && ($i<count($darr)); $i++) if ($darr[$i]!=""){
fseek ($i2cctl, i2c_bus353($bus)*$size+$i) ;
fwrite($i2cctl, chr($darr[$i]+0), 1);
}
fclose($i2cctl);
}
$i2cctl = fopen('/dev/xi2cctl', 'r');
fseek ($i2cctl, i2c_bus353($bus)*$size) ;
$data = fread($i2cctl, $size);
fclose($i2cctl);
$xml = new SimpleXMLElement("<?xml version='1.0'?><i2cctl/>");
$xml->addChild ('scl_high',ord($data[0]));
$xml->addChild ('scl_low', ord($data[1]));
$xml->addChild ('slave2master', ord($data[2]));
$xml->addChild ('master2slave', ord($data[3]));
$xml->addChild ('filter_sda', ord($data[4]));
$xml->addChild ('filter_scl', ord($data[5]));
// $data=$xml->asXML();
return $xml;
} // end of i2c_ctl()
function i2c_ctl_arr($bus,$darr=array()) { //!$data - 6-element array
$size=6; // bytes per bus
if (count($darr)>00) {
$i2cctl = fopen('/dev/xi2cctl', 'w');
for ($i=0; ($i<$size) && ($i<count($darr)); $i++) if ($darr[$i]!=""){
fseek ($i2cctl, i2c_bus353($bus)*$size+$i) ;
fwrite($i2cctl, chr($darr[$i]+0), 1);
}
fclose($i2cctl);
}
$i2cctl = fopen('/dev/xi2cctl', 'r');
fseek ($i2cctl, i2c_bus353($bus)*$size) ;
$data = fread($i2cctl, $size);
fclose($i2cctl);
for ($i=0;$i<$size; $i++) $darr[$i]=ord($data[$i]);
return $darr;
} // end of i2c_ctl()
function i2c_send($width, $bus, $a, $d, $raw = 0) { // $a<0 - use raw read/write
if ($bus < 4)
return i2c_send_sensor ( $width, $bus, $a, $d, $raw );
else
$bus = i2c_bus353 ( $bus );
if ($bus == 2) { // System i2c in nc393 (was 5)
$return = -1;
$w = ($width == 16) ?'w' : 'b';
$sa7r = aw_to_sa7r($a,$width); // works for raw also, $width is 8 for raw
if ($raw){
exec ( 'i2cset -y 0 '.$sa7r[0].' '.$d, $i2c_data, $return );
} else {
exec ( 'i2cget -y 0 '.$sa7r[0].' '.$sa7r[1].' '.$d.' '.$w, $i2c_data, $return );
}
if ($return != 0) return -1;
return ($width == 16)?2:1;
}
$w = ($width == 16) ? 2 : 1;
$i2c_fn = '/dev/xi2c' . ($raw ? 'raw' : (($w == 2) ? '16' : '8')) . (($bus == 0) ? '' : '_aux');
$i2c = fopen ( $i2c_fn, 'w' );
fseek ( $i2c, $w * $a );
if ($w == 1)
$res = fwrite ( $i2c, chr ( $d ) );
else
$res = fwrite ( $i2c, chr ( floor ( $d / 256 ) ) . chr ( $d - 256 * floor ( $d / 256 ) ) );
fclose ( $i2c );
return $res;
} // end of i2c_send()
// Seems no difference from i2c_send for nc393
function i2c_send_slow($width, $bus, $a, $d, $raw = 0, $extrausec = -1) { // $a<0 - use raw read/write
if ($bus < 4)
return i2c_send_sensor ( $width, $bus, $a, $d, $raw );
else
$bus = i2c_bus353 ( $bus );
if (($bus == 0) && ($extrausec >= 0)) {
$i2c_old_ctrl = i2c_ctl_arr ( 0 );
i2c_ctl_arr ( 0, getSlowArray ( $extrausec ) );
}
if ($bus == 2) { // System i2c in nc393 (was 5)
$return = -1;
$w = ($width == 16) ?'w' : 'b';
$sa7r = aw_to_sa7r($a,$width); // works for raw also, $width is 8 for raw
if ($raw){
exec ( 'i2cset -y 0 '.$sa7r[0].' '.$d, $i2c_data, $return );
} else {
exec ( 'i2cget -y 0 '.$sa7r[0].' '.$sa7r[1].' '.$d.' '.$w, $i2c_data, $return );
}
if ($return != 0) return -1;
return ($width == 16)?2:1;
}
$w = ($width == 16) ? 2 : 1;
$i2c_fn = '/dev/xi2c' . ($raw ? 'raw' : (($w == 2) ? '16' : '8')) . (($bus == 0) ? '' : '_aux');
$i2c = fopen ( $i2c_fn, 'w' );
fseek ( $i2c, $w * $a );
if ($w == 1)
$res = fwrite ( $i2c, chr ( $d ) );
else
$res = fwrite ( $i2c, chr ( floor ( $d / 256 ) ) . chr ( $d - 256 * floor ( $d / 256 ) ) );
fclose ( $i2c );
if (($bus == 0) && ($extrausec >= 0)) {
i2c_ctl_arr ( 0, $i2c_old_ctrl ); // / restore old speed (not thread-safe)
}
return $res;
} // end of i2c_send()
function smbus_send($a, $d) { // d - array
$i2c_fn = '/dev/xi2c8_aux';
$i2c = fopen ( $i2c_fn, 'w' );
fseek ( $i2c, $a );
$cmd = chr ( count ( $d ) );
foreach ( $d as $b )
$cmd .= chr ( $b );
// var_dump($cmd);
$res = fwrite ( $i2c, $cmd );
fclose ( $i2c );
return $res;
} // end of i2c_send()
function i2c_receive($width, $bus, $a, $raw = 0) {
if ($bus < 4)
return i2c_receive_sensor ( $width, $bus, $a, $raw );
else
$bus = i2c_bus353 ( $bus );
if ($bus == 2) { // System i2c in nc393 (was 5)
$w = ($width == 16) ?'w' : 'b';
$sa7r = aw_to_sa7r($a,$width); // works for raw also, $width is 8 for raw
if ($raw){
exec ( 'i2cget -y 0 '.$sa7r[0], $i2c_data, $return );
} else {
exec ( 'i2cget -y 0 '.$sa7r[0].' '.$sa7r[1].' '.$w, $i2c_data, $return );
}
if ($return != 0) return -1;
return $i2c_data[0];
}
$w = ($width == 16) ? 2 : 1;
$i2c_fn = '/dev/xi2c' . ($raw ? 'raw' : (($w == 2) ? '16' : '8')) . (($bus == 0) ? '' : '_aux');
$i2c = fopen ( $i2c_fn, 'r' );
fseek ( $i2c, $w * $a );
$data = fread ( $i2c, $w );
fclose ( $i2c );
if (strlen ( $data ) < $w)
return - 1;
$v = unpack ( ($w == 1) ? 'C' : 'n1', $data );
return $v [1];
} // end of i2c_receive()
// i2c_receive_slow is the same as i2c_receive for nc393
function i2c_receive_slow($width, $bus, $a, $raw = 0, $extrausec = -1) {
if ($bus < 4)
return i2c_receive_sensor ( $width, $bus, $a, $raw );
else
$bus = i2c_bus353 ( $bus );
if (($bus == 0) && ($extrausec >= 0)) {
$i2c_old_ctrl = i2c_ctl_arr ( 0 );
i2c_ctl_arr ( 0, getSlowArray ( $extrausec ) );
}
if ($bus == 2) { // System i2c in nc393 (was 5)
$w = ($width == 16) ?'w' : 'b';
$sa7r = aw_to_sa7r($a,$width); // works for raw also, $width is 8 for raw
if ($raw){
exec ( 'i2cget -y 0 '.$sa7r[0], $i2c_data, $return );
} else {
exec ( 'i2cget -y 0 '.$sa7r[0].' '.$sa7r[1].' '.$w, $i2c_data, $return );
}
if ($return != 0) return -1;
return $i2c_data[0];
}
$w = ($width == 16) ? 2 : 1;
$i2c_fn = '/dev/xi2c' . ($raw ? 'raw' : (($w == 2) ? '16' : '8')) . (($bus == 0) ? '' : '_aux');
$i2c = fopen ( $i2c_fn, 'r' );
fseek ( $i2c, $w * $a );
$data = fread ( $i2c, $w );
fclose ( $i2c );
if (strlen ( $data ) < $w)
return - 1;
$v = unpack ( ($w == 1) ? 'C' : 'n1', $data );
if ($bus == 0) {
i2c_ctl_arr ( 0, $i2c_old_ctrl ); // / restore old speed (not thread-safe)
}
return $v [1];
} // end of i2c_receive()
function i2c_setprot($bus, $slave, $bit, $value) { // !slave is MSB aligned, LSB==0)
if ($bus != 4)
return -1; // applicable only to grand-daughter i2c (like imu, gps)
$bus = i2c_bus353 ( $bus );
$i2cprot = fopen ("/dev/xi2cenable", 'r+' );
fseek ( $i2cprot, ($bus * 128) + ($slave >> 1) );
$data = ord ( fread ( $i2cprot, 1 ) );
if ($value)
$data |= (1 << $bit);
else
$data &= ~ (1 << $bit);
fseek ( $i2cprot, ($bus * 128) + ($slave >> 1) );
fwrite ( $i2cprot, chr ( $data ) );
fclose ( $i2cprot );
} // end of i2c_setprot ()
function i2c_getCMOSClock() {
echo "**** FUNCTION NOT SUPPORTED in NC393 *****";
return - 1;
$i2c = fopen ( '/dev/xi2c8_aux', 'r' );
fseek ( $i2c, 0x5102 ); // seconds in clock on the 10369 board
$data = fread ( $i2c, 7 ); // sec/min/hours/days/weekdays/century-months/years, BCD
fclose ( $i2c );
if (strlen ( $data ) < 7)
return "error";
$v = unpack ( 'C*', $data );
$d = array (
"sec" => ($v [1] & 0xf) + 10 * (($v [1] >> 4) & 0x7),
"min" => ($v [2] & 0xf) + 10 * (($v [2] >> 4) & 0x7),
"hrs" => ($v [3] & 0xf) + 10 * (($v [3] >> 4) & 0x3),
"day" => ($v [4] & 0xf) + 10 * (($v [4] >> 4) & 0x3),
"wday" => $v [5] & 0x7,
"month" => ($v [6] & 0xf) + 10 * (($v [6] >> 4) & 0x1),
"year" => ($v [7] & 0xf) + 10 * (($v [7] >> 4) & 0xf) + (($v [6] & 0x80) ? 2000 : 1900)
);
exec ( "date -s " . sprintf ( "%02d%02d%02d%02d%04d.%02d", $d ["month"], $d ["day"], $d ["hrs"], $d ["min"], $d ["year"], $d ["sec"] ), $out, $ret );
if ($ret == 0) {
elphel_set_fpga_time ( time () + 0.0 );
}
return $ret;
} // end of i2c_getCMOSClock()
function i2c_bcd($v) {
$d=intval($v,10);
return $d + 6*floor($d/10);
} // end of i2c_bcd($v)
function i2c_setCMOSClock(){
$ts=time();
$data=chr(i2c_bcd(gmdate("s",$ts))).
chr(i2c_bcd(gmdate("i",$ts))).
chr(i2c_bcd(gmdate("H",$ts))).
chr(i2c_bcd(gmdate("d",$ts))).
chr(i2c_bcd(gmdate("w",$ts))).
chr(i2c_bcd(gmdate("m",$ts))+ ((intval(gmdate("Y",$ts),10)>=2000)?0x80:0)).
chr(i2c_bcd(gmdate("y",$ts)));
$i2c = fopen('/dev/xi2c8_aux', 'w');
fseek ($i2c, 0x5102) ; //seconds in clock on the 10369 board
$written= fwrite($i2c, $data);
fclose($i2c);
if ($written < strlen($data)) return "error";
return "OK";
} // end of i2c_setCMOSClock()
function i2c_read256b($slave = 0xa0, $bus = 4, $extrausec = 0) { // will read 256 bytes from slave (address is 8-bit, includes r/~w)
if ($bus < 4)
return i2c_read256b_sensor ( $slave, $bus, $extrausec ); // ($name, $sensor_port, $sa7_offset)
else
$bus = i2c_bus353 ( $bus );
if (($bus == 0) && ($extrausec >= 0)) {
$i2c_old_ctrl = i2c_ctl_arr ( 0 );
i2c_ctl_arr ( 0, getSlowArray ( $extrausec ) );
}
if ($bus == 2) { // System i2c in nc393 (was 5)
$sa7 = $slave >> 1;
/* // very slow
for($i = 0; $i < 256; $i ++) {
exec ( 'i2cget -y 0 ' . $sa7 . ' ' . $i . ' b', $i2c_data, $return );
if ($return != 0)
return - 1;
}
$data == "";
foreach ($i2c_data as $c) $data.=chr($c);
*/
exec('i2cdump -y 0 ' . $sa7 . ' b', $i2c_data, $return );
if ($return != 0) return - 1;
// Extract data from dump table
$line="";
for ($j=0; $j<16; $j++) $line .= substr($i2c_data[$j+1],4,48);
$data == "";
foreach (explode(' ',$line) as $e) $data.=chr(intval($e,16));
return $data;
}
$i2c_fn = '/dev/xi2c8' . (($bus == 0) ? '' : '_aux');
$i2c = fopen ( $i2c_fn, 'r' );
fseek ( $i2c, $slave * 128 ); // 256 per slave, but slave are only even
$data = fread ( $i2c, 256 ); // full 256 bytes
fclose ( $i2c );
if (($bus == 0) && ($extrausec >= 0)) {
i2c_ctl_arr ( 0, $i2c_old_ctrl ); // / restore old speed (not thread-safe)
}
return $data;
} // end of i2c_read256b ()
//this EEPROM writes only 4 bytes sequentionally (only 2 LSBs are incremented)
function i2c_write256b($data, $slave = 0xa0, $bus = 4, $extrausec = 0) { // will write up to 256 bytes $data to slave (address is 8-bit, includes r/~w). EEPROM should be un-protected
if ($bus < 4)
return i2c_write256b_sensor ( $data, $slave, $bus, $extrausec ); // ($data, $name, $sensor_port, $sa7_offset)
else
$bus = i2c_bus353 ( $bus );
if (($bus == 0) && ($extrausec >= 0)) {
$i2c_old_ctrl = i2c_ctl_arr ( 0 );
i2c_ctl_arr ( 0, getSlowArray ( $extrausec ) );
}
$maxretries = 200; // measured - 19
$len = 0;
if (! is_string ( $data ))
return - 1;
if (strlen ( $data ) > 256)
return - 2;
if (strlen ( $data ) < 256)
$data .= chr ( 0 );
if ($bus == 2) { // System i2c in nc393 (was 5)
$sa7 = $slave >> 1;
foreach (str_split($data) as $d) {
exec ( 'i2cset -y 0 ' . $sa7 . ' ' .$len . ' ' . ord($d) . ' b', $i2c_data, $return );
if ($return != 0)
return - 1;
usleep ( 10000 );
$len ++;
}
return $len;
}
//foreach (str_split($data) as $d) echo ord($d);
$i2c_fn = '/dev/xi2c8' . (($bus == 0) ? '' : '_aux');
$i2c = fopen ( $i2c_fn, 'w' );
for($i = 0; $i < strlen ( $data ); $i += 4) {
for($retry = 0; $retry < $maxretries; $retry ++) {
fseek ( $i2c, $slave * 128 + $i ); // 256 per slave, but slave are only even
$rslt = fwrite ( $i2c, substr ( $data, $i, 4 ) );
if ($rslt > 0)
break;
}
if ($rslt <= 0) {
$len = $rslt;
break;
}
$len += $rslt;
}
fclose ( $i2c );
if (($bus == 0) && ($extrausec >= 0)) {
i2c_ctl_arr ( 0, $i2c_old_ctrl ); // / restore old speed (not thread-safe)
}
return $len;
} // end of i2c_write256b ()
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