+++ /dev/null
-Kernel driver eeprom
-====================
-
-Supported chips:
- * Any EEPROM chip in the designated address range
- Prefix: 'eeprom'
- Addresses scanned: I2C 0x50 - 0x57
- Datasheets: Publicly available from:
- Atmel (www.atmel.com),
- Catalyst (www.catsemi.com),
- Fairchild (www.fairchildsemi.com),
- Microchip (www.microchip.com),
- Philips (www.semiconductor.philips.com),
- Rohm (www.rohm.com),
- ST (www.st.com),
- Xicor (www.xicor.com),
- and others.
-
- Chip Size (bits) Address
- 24C01 1K 0x50 (shadows at 0x51 - 0x57)
- 24C01A 1K 0x50 - 0x57 (Typical device on DIMMs)
- 24C02 2K 0x50 - 0x57
- 24C04 4K 0x50, 0x52, 0x54, 0x56
- (additional data at 0x51, 0x53, 0x55, 0x57)
- 24C08 8K 0x50, 0x54 (additional data at 0x51, 0x52,
- 0x53, 0x55, 0x56, 0x57)
- 24C16 16K 0x50 (additional data at 0x51 - 0x57)
- Sony 2K 0x57
-
- Atmel 34C02B 2K 0x50 - 0x57, SW write protect at 0x30-37
- Catalyst 34FC02 2K 0x50 - 0x57, SW write protect at 0x30-37
- Catalyst 34RC02 2K 0x50 - 0x57, SW write protect at 0x30-37
- Fairchild 34W02 2K 0x50 - 0x57, SW write protect at 0x30-37
- Microchip 24AA52 2K 0x50 - 0x57, SW write protect at 0x30-37
- ST M34C02 2K 0x50 - 0x57, SW write protect at 0x30-37
-
-
-Authors:
- Frodo Looijaard <frodol@dds.nl>,
- Philip Edelbrock <phil@netroedge.com>,
- Jean Delvare <khali@linux-fr.org>,
- Greg Kroah-Hartman <greg@kroah.com>,
- IBM Corp.
-
-Description
------------
-
-This is a simple EEPROM module meant to enable reading the first 256 bytes
-of an EEPROM (on a SDRAM DIMM for example). However, it will access serial
-EEPROMs on any I2C adapter. The supported devices are generically called
-24Cxx, and are listed above; however the numbering for these
-industry-standard devices may vary by manufacturer.
-
-This module was a programming exercise to get used to the new project
-organization laid out by Frodo, but it should be at least completely
-effective for decoding the contents of EEPROMs on DIMMs.
-
-DIMMS will typically contain a 24C01A or 24C02, or the 34C02 variants.
-The other devices will not be found on a DIMM because they respond to more
-than one address.
-
-DDC Monitors may contain any device. Often a 24C01, which responds to all 8
-addresses, is found.
-
-Recent Sony Vaio laptops have an EEPROM at 0x57. We couldn't get the
-specification, so it is guess work and far from being complete.
-
-The Microchip 24AA52/24LCS52, ST M34C02, and others support an additional
-software write protect register at 0x30 - 0x37 (0x20 less than the memory
-location). The chip responds to "write quick" detection at this address but
-does not respond to byte reads. If this register is present, the lower 128
-bytes of the memory array are not write protected. Any byte data write to
-this address will write protect the memory array permanently, and the
-device will no longer respond at the 0x30-37 address. The eeprom driver
-does not support this register.
-
-Lacking functionality:
-
-* Full support for larger devices (24C04, 24C08, 24C16). These are not
-typically found on a PC. These devices will appear as separate devices at
-multiple addresses.
-
-* Support for really large devices (24C32, 24C64, 24C128, 24C256, 24C512).
-These devices require two-byte address fields and are not supported.
-
-* Enable Writing. Again, no technical reason why not, but making it easy
-to change the contents of the EEPROMs (on DIMMs anyway) also makes it easy
-to disable the DIMMs (potentially preventing the computer from booting)
-until the values are restored somehow.
-
-Use:
-
-After inserting the module (and any other required SMBus/i2c modules), you
-should have some EEPROM directories in /sys/bus/i2c/devices/* of names such
-as "0-0050". Inside each of these is a series of files, the eeprom file
-contains the binary data from EEPROM.
+++ /dev/null
-Kernel driver max6875
-=====================
-
-Supported chips:
- * Maxim MAX6874, MAX6875
- Prefix: 'max6875'
- Addresses scanned: None (see below)
- Datasheet:
- http://pdfserv.maxim-ic.com/en/ds/MAX6874-MAX6875.pdf
-
-Author: Ben Gardner <bgardner@wabtec.com>
-
-
-Description
------------
-
-The Maxim MAX6875 is an EEPROM-programmable power-supply sequencer/supervisor.
-It provides timed outputs that can be used as a watchdog, if properly wired.
-It also provides 512 bytes of user EEPROM.
-
-At reset, the MAX6875 reads the configuration EEPROM into its configuration
-registers. The chip then begins to operate according to the values in the
-registers.
-
-The Maxim MAX6874 is a similar, mostly compatible device, with more intputs
-and outputs:
- vin gpi vout
-MAX6874 6 4 8
-MAX6875 4 3 5
-
-See the datasheet for more information.
-
-
-Sysfs entries
--------------
-
-eeprom - 512 bytes of user-defined EEPROM space.
-
-
-General Remarks
----------------
-
-Valid addresses for the MAX6875 are 0x50 and 0x52.
-Valid addresses for the MAX6874 are 0x50, 0x52, 0x54 and 0x56.
-The driver does not probe any address, so you must force the address.
-
-Example:
-$ modprobe max6875 force=0,0x50
-
-The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple
-addresses. For example, for address 0x50, it also reserves 0x51.
-The even-address instance is called 'max6875', the odd one is 'dummy'.
-
-
-Programming the chip using i2c-dev
-----------------------------------
-
-Use the i2c-dev interface to access and program the chips.
-Reads and writes are performed differently depending on the address range.
-
-The configuration registers are at addresses 0x00 - 0x45.
-Use i2c_smbus_write_byte_data() to write a register and
-i2c_smbus_read_byte_data() to read a register.
-The command is the register number.
-
-Examples:
-To write a 1 to register 0x45:
- i2c_smbus_write_byte_data(fd, 0x45, 1);
-
-To read register 0x45:
- value = i2c_smbus_read_byte_data(fd, 0x45);
-
-
-The configuration EEPROM is at addresses 0x8000 - 0x8045.
-The user EEPROM is at addresses 0x8100 - 0x82ff.
-
-Use i2c_smbus_write_word_data() to write a byte to EEPROM.
-
-The command is the upper byte of the address: 0x80, 0x81, or 0x82.
-The data word is the lower part of the address or'd with data << 8.
- cmd = address >> 8;
- val = (address & 0xff) | (data << 8);
-
-Example:
-To write 0x5a to address 0x8003:
- i2c_smbus_write_word_data(fd, 0x80, 0x5a03);
-
-
-Reading data from the EEPROM is a little more complicated.
-Use i2c_smbus_write_byte_data() to set the read address and then
-i2c_smbus_read_byte() or i2c_smbus_read_i2c_block_data() to read the data.
-
-Example:
-To read data starting at offset 0x8100, first set the address:
- i2c_smbus_write_byte_data(fd, 0x81, 0x00);
-
-And then read the data
- value = i2c_smbus_read_byte(fd);
-
- or
-
- count = i2c_smbus_read_i2c_block_data(fd, 0x84, 16, buffer);
-
-The block read should read 16 bytes.
-0x84 is the block read command.
-
-See the datasheet for more details.
-
--- /dev/null
+Kernel driver eeprom
+====================
+
+Supported chips:
+ * Any EEPROM chip in the designated address range
+ Prefix: 'eeprom'
+ Addresses scanned: I2C 0x50 - 0x57
+ Datasheets: Publicly available from:
+ Atmel (www.atmel.com),
+ Catalyst (www.catsemi.com),
+ Fairchild (www.fairchildsemi.com),
+ Microchip (www.microchip.com),
+ Philips (www.semiconductor.philips.com),
+ Rohm (www.rohm.com),
+ ST (www.st.com),
+ Xicor (www.xicor.com),
+ and others.
+
+ Chip Size (bits) Address
+ 24C01 1K 0x50 (shadows at 0x51 - 0x57)
+ 24C01A 1K 0x50 - 0x57 (Typical device on DIMMs)
+ 24C02 2K 0x50 - 0x57
+ 24C04 4K 0x50, 0x52, 0x54, 0x56
+ (additional data at 0x51, 0x53, 0x55, 0x57)
+ 24C08 8K 0x50, 0x54 (additional data at 0x51, 0x52,
+ 0x53, 0x55, 0x56, 0x57)
+ 24C16 16K 0x50 (additional data at 0x51 - 0x57)
+ Sony 2K 0x57
+
+ Atmel 34C02B 2K 0x50 - 0x57, SW write protect at 0x30-37
+ Catalyst 34FC02 2K 0x50 - 0x57, SW write protect at 0x30-37
+ Catalyst 34RC02 2K 0x50 - 0x57, SW write protect at 0x30-37
+ Fairchild 34W02 2K 0x50 - 0x57, SW write protect at 0x30-37
+ Microchip 24AA52 2K 0x50 - 0x57, SW write protect at 0x30-37
+ ST M34C02 2K 0x50 - 0x57, SW write protect at 0x30-37
+
+
+Authors:
+ Frodo Looijaard <frodol@dds.nl>,
+ Philip Edelbrock <phil@netroedge.com>,
+ Jean Delvare <khali@linux-fr.org>,
+ Greg Kroah-Hartman <greg@kroah.com>,
+ IBM Corp.
+
+Description
+-----------
+
+This is a simple EEPROM module meant to enable reading the first 256 bytes
+of an EEPROM (on a SDRAM DIMM for example). However, it will access serial
+EEPROMs on any I2C adapter. The supported devices are generically called
+24Cxx, and are listed above; however the numbering for these
+industry-standard devices may vary by manufacturer.
+
+This module was a programming exercise to get used to the new project
+organization laid out by Frodo, but it should be at least completely
+effective for decoding the contents of EEPROMs on DIMMs.
+
+DIMMS will typically contain a 24C01A or 24C02, or the 34C02 variants.
+The other devices will not be found on a DIMM because they respond to more
+than one address.
+
+DDC Monitors may contain any device. Often a 24C01, which responds to all 8
+addresses, is found.
+
+Recent Sony Vaio laptops have an EEPROM at 0x57. We couldn't get the
+specification, so it is guess work and far from being complete.
+
+The Microchip 24AA52/24LCS52, ST M34C02, and others support an additional
+software write protect register at 0x30 - 0x37 (0x20 less than the memory
+location). The chip responds to "write quick" detection at this address but
+does not respond to byte reads. If this register is present, the lower 128
+bytes of the memory array are not write protected. Any byte data write to
+this address will write protect the memory array permanently, and the
+device will no longer respond at the 0x30-37 address. The eeprom driver
+does not support this register.
+
+Lacking functionality:
+
+* Full support for larger devices (24C04, 24C08, 24C16). These are not
+typically found on a PC. These devices will appear as separate devices at
+multiple addresses.
+
+* Support for really large devices (24C32, 24C64, 24C128, 24C256, 24C512).
+These devices require two-byte address fields and are not supported.
+
+* Enable Writing. Again, no technical reason why not, but making it easy
+to change the contents of the EEPROMs (on DIMMs anyway) also makes it easy
+to disable the DIMMs (potentially preventing the computer from booting)
+until the values are restored somehow.
+
+Use:
+
+After inserting the module (and any other required SMBus/i2c modules), you
+should have some EEPROM directories in /sys/bus/i2c/devices/* of names such
+as "0-0050". Inside each of these is a series of files, the eeprom file
+contains the binary data from EEPROM.
--- /dev/null
+Kernel driver max6875
+=====================
+
+Supported chips:
+ * Maxim MAX6874, MAX6875
+ Prefix: 'max6875'
+ Addresses scanned: None (see below)
+ Datasheet:
+ http://pdfserv.maxim-ic.com/en/ds/MAX6874-MAX6875.pdf
+
+Author: Ben Gardner <bgardner@wabtec.com>
+
+
+Description
+-----------
+
+The Maxim MAX6875 is an EEPROM-programmable power-supply sequencer/supervisor.
+It provides timed outputs that can be used as a watchdog, if properly wired.
+It also provides 512 bytes of user EEPROM.
+
+At reset, the MAX6875 reads the configuration EEPROM into its configuration
+registers. The chip then begins to operate according to the values in the
+registers.
+
+The Maxim MAX6874 is a similar, mostly compatible device, with more intputs
+and outputs:
+ vin gpi vout
+MAX6874 6 4 8
+MAX6875 4 3 5
+
+See the datasheet for more information.
+
+
+Sysfs entries
+-------------
+
+eeprom - 512 bytes of user-defined EEPROM space.
+
+
+General Remarks
+---------------
+
+Valid addresses for the MAX6875 are 0x50 and 0x52.
+Valid addresses for the MAX6874 are 0x50, 0x52, 0x54 and 0x56.
+The driver does not probe any address, so you must force the address.
+
+Example:
+$ modprobe max6875 force=0,0x50
+
+The MAX6874/MAX6875 ignores address bit 0, so this driver attaches to multiple
+addresses. For example, for address 0x50, it also reserves 0x51.
+The even-address instance is called 'max6875', the odd one is 'dummy'.
+
+
+Programming the chip using i2c-dev
+----------------------------------
+
+Use the i2c-dev interface to access and program the chips.
+Reads and writes are performed differently depending on the address range.
+
+The configuration registers are at addresses 0x00 - 0x45.
+Use i2c_smbus_write_byte_data() to write a register and
+i2c_smbus_read_byte_data() to read a register.
+The command is the register number.
+
+Examples:
+To write a 1 to register 0x45:
+ i2c_smbus_write_byte_data(fd, 0x45, 1);
+
+To read register 0x45:
+ value = i2c_smbus_read_byte_data(fd, 0x45);
+
+
+The configuration EEPROM is at addresses 0x8000 - 0x8045.
+The user EEPROM is at addresses 0x8100 - 0x82ff.
+
+Use i2c_smbus_write_word_data() to write a byte to EEPROM.
+
+The command is the upper byte of the address: 0x80, 0x81, or 0x82.
+The data word is the lower part of the address or'd with data << 8.
+ cmd = address >> 8;
+ val = (address & 0xff) | (data << 8);
+
+Example:
+To write 0x5a to address 0x8003:
+ i2c_smbus_write_word_data(fd, 0x80, 0x5a03);
+
+
+Reading data from the EEPROM is a little more complicated.
+Use i2c_smbus_write_byte_data() to set the read address and then
+i2c_smbus_read_byte() or i2c_smbus_read_i2c_block_data() to read the data.
+
+Example:
+To read data starting at offset 0x8100, first set the address:
+ i2c_smbus_write_byte_data(fd, 0x81, 0x00);
+
+And then read the data
+ value = i2c_smbus_read_byte(fd);
+
+ or
+
+ count = i2c_smbus_read_i2c_block_data(fd, 0x84, 16, buffer);
+
+The block read should read 16 bytes.
+0x84 is the block read command.
+
+See the datasheet for more details.
+
projects / openwrt / staging / blogic.git / commitdiff