Merge tag 'for-linus-3.5-20120601' of git://git.infradead.org/linux-mtd

		half page, or a quarter page).

		In the case of ECC NOR, it is the ECC block size.

What:		/sys/class/mtd/mtdX/ecc_strength

Date:		April 2012

KernelVersion:	3.4

Contact:	linux-mtd@lists.infradead.org

Description:

		Maximum number of bit errors that the device is capable of

		correcting within each region covering an ecc step.  This will

		always be a non-negative integer.  Note that some devices will

		have multiple ecc steps within each writesize region.

		In the case of devices lacking any ECC capability, it is 0.

What:		/sys/class/mtd/mtdX/bitflip_threshold

Date:		April 2012

KernelVersion:	3.4

Contact:	linux-mtd@lists.infradead.org

Description:

		This allows the user to examine and adjust the criteria by which

		mtd returns -EUCLEAN from mtd_read().  If the maximum number of

		bit errors that were corrected on any single region comprising

		an ecc step (as reported by the driver) equals or exceeds this

		value, -EUCLEAN is returned.  Otherwise, absent an error, 0 is

		returned.  Higher layers (e.g., UBI) use this return code as an

		indication that an erase block may be degrading and should be

		scrutinized as a candidate for being marked as bad.

		The initial value may be specified by the flash device driver.

		If not, then the default value is ecc_strength.

		The introduction of this feature brings a subtle change to the

		meaning of the -EUCLEAN return code.  Previously, it was

		interpreted to mean simply "one or more bit errors were

		corrected".  Its new interpretation can be phrased as "a

		dangerously high number of bit errors were corrected on one or

		more regions comprising an ecc step".  The precise definition of

		"dangerously high" can be adjusted by the user with

		bitflip_threshold.  Users are discouraged from doing this,

		however, unless they know what they are doing and have intimate

		knowledge of the properties of their device.  Broadly speaking,

		bitflip_threshold should be low enough to detect genuine erase

		block degradation, but high enough to avoid the consequences of

		a persistent return value of -EUCLEAN on devices where sticky

		bitflips occur.  Note that if bitflip_threshold exceeds

		ecc_strength, -EUCLEAN is never returned by mtd_read().

		Conversely, if bitflip_threshold is zero, -EUCLEAN is always

		returned, absent a hard error.

		This is generally applicable only to NAND flash devices with ECC

		capability.  It is ignored on devices lacking ECC capability;

		i.e., devices for which ecc_strength is zero.

		These constants are defined in nand.h. They are ored together to describe

		the chip functionality.

     		<programlisting>

/* Chip can not auto increment pages */

#define NAND_NO_AUTOINCR	0x00000001

/* Buswitdh is 16 bit */

#define NAND_BUSWIDTH_16	0x00000002

/* Device supports partial programming without padding */

* Freescale General-Purpose Media Interface (GPMI)

The GPMI nand controller provides an interface to control the

NAND flash chips. We support only one NAND chip now.

Required properties:

  - compatible : should be "fsl,<chip>-gpmi-nand"

  - reg : should contain registers location and length for gpmi and bch.

  - reg-names: Should contain the reg names "gpmi-nand" and "bch"

  - interrupts : The first is the DMA interrupt number for GPMI.

                 The second is the BCH interrupt number.

  - interrupt-names : The interrupt names "gpmi-dma", "bch";

  - fsl,gpmi-dma-channel : Should contain the dma channel it uses.

The device tree may optionally contain sub-nodes describing partitions of the

address space. See partition.txt for more detail.

Examples:

gpmi-nand@8000c000 {

	compatible = "fsl,imx28-gpmi-nand";

	#address-cells = <1>;

	#size-cells = <1>;

	reg = <0x8000c000 2000>, <0x8000a000 2000>;

	reg-names = "gpmi-nand", "bch";

	interrupts = <88>, <41>;

	interrupt-names = "gpmi-dma", "bch";

	fsl,gpmi-dma-channel = <4>;

	partition@0 {

	...

	};

};

* Freescale's mxc_nand

Required properties:

- compatible: "fsl,imxXX-nand"

- reg: address range of the nfc block

- interrupts: irq to be used

- nand-bus-width: see nand.txt

- nand-ecc-mode: see nand.txt

- nand-on-flash-bbt: see nand.txt

Example:

	nand@d8000000 {

		compatible = "fsl,imx27-nand";

		reg = <0xd8000000 0x1000>;

		interrupts = <29>;

		nand-bus-width = <8>;

		nand-ecc-mode = "hw";

	};

				status = "disabled";

			};

		};

		nand@d8000000 {

			#address-cells = <1>;

			#size-cells = <1>;

			compatible = "fsl,imx27-nand";

			reg = <0xd8000000 0x1000>;

			interrupts = <29>;

			status = "disabled";

		};

	};

};