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821e2c705f
As the at25 uses the NVMEM subsystem, and the property is now being handled, adding reference for it in the device tree binding document, which allows to specify the GPIO line to which the write-protect pin is connected. Signed-off-by: Khouloud Touil <ktouil@baylibre.com> Reviewed-by: Rob Herring <robh@kernel.org> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
46 lines
1.4 KiB
Plaintext
46 lines
1.4 KiB
Plaintext
EEPROMs (SPI) compatible with Atmel at25.
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Required properties:
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- compatible : Should be "<vendor>,<type>", and generic value "atmel,at25".
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Example "<vendor>,<type>" values:
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"anvo,anv32e61w"
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"microchip,25lc040"
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"st,m95m02"
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"st,m95256"
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- reg : chip select number
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- spi-max-frequency : max spi frequency to use
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- pagesize : size of the eeprom page
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- size : total eeprom size in bytes
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- address-width : number of address bits (one of 8, 9, 16, or 24).
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For 9 bits, the MSB of the address is sent as bit 3 of the instruction
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byte, before the address byte.
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Optional properties:
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- spi-cpha : SPI shifted clock phase, as per spi-bus bindings.
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- spi-cpol : SPI inverse clock polarity, as per spi-bus bindings.
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- read-only : this parameter-less property disables writes to the eeprom
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- wp-gpios : GPIO to which the write-protect pin of the chip is connected
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Obsolete legacy properties can be used in place of "size", "pagesize",
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"address-width", and "read-only":
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- at25,byte-len : total eeprom size in bytes
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- at25,addr-mode : addr-mode flags, as defined in include/linux/spi/eeprom.h
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- at25,page-size : size of the eeprom page
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Additional compatible properties are also allowed.
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Example:
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eeprom@0 {
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compatible = "st,m95256", "atmel,at25";
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reg = <0>
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spi-max-frequency = <5000000>;
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spi-cpha;
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spi-cpol;
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wp-gpios = <&gpio1 3 0>;
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pagesize = <64>;
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size = <32768>;
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address-width = <16>;
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};
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