Merge branch 'master' into for-linus

What:		/sys/class/power/ds2760-battery.*/charge_now

Date:		May 2010

KernelVersion:	2.6.35

Contact:	Daniel Mack <daniel@caiaq.de>

Description:

		This file is writeable and can be used to set the current

		coloumb counter value inside the battery monitor chip. This

		is needed for unavoidable corrections of aging batteries.

		A userspace daemon can monitor the battery charging logic

		and once the counter drops out of considerable bounds, take

		appropriate action.

What:		/sys/class/power/ds2760-battery.*/charge_full

Date:		May 2010

KernelVersion:	2.6.35

Contact:	Daniel Mack <daniel@caiaq.de>

Description:

		This file is writeable and can be used to set the assumed

		battery 'full level'. As batteries age, this value has to be

		amended over time.

What:		/sys/devices/system/node/nodeX/compact

Date:		February 2010

Contact:	Mel Gorman <mel@csn.ul.ie>

Description:

		When this file is written to, all memory within that node

		will be compacted. When it completes, memory will be freed

		into blocks which have as many contiguous pages as possible

What:		/sys/firmware/sfi/tables/

Date:		May 2010

Contact:	Len Brown <lenb@kernel.org>

Description:

		SFI defines a number of small static memory tables

		so the kernel can get platform information from firmware.

		The tables are defined in the latest SFI specification:

		http://simplefirmware.org/documentation

		While the tables are used by the kernel, user-space

		can observe them this way:

		# cd /sys/firmware/sfi/tables

		# cat $TABLENAME > $TABLENAME.bin

they are entirely deprecated.  Some ports already do not provide these

as it is impossible to correctly support them.

			Handling Errors

DMA address space is limited on some architectures and an allocation

failure can be determined by:

- checking if dma_alloc_coherent returns NULL or dma_map_sg returns 0

- checking the returned dma_addr_t of dma_map_single and dma_map_page

  by using dma_mapping_error():

	dma_addr_t dma_handle;

	dma_handle = dma_map_single(dev, addr, size, direction);

	if (dma_mapping_error(dev, dma_handle)) {

		/*

		 * reduce current DMA mapping usage,

		 * delay and try again later or

		 * reset driver.

		 */

	}

Networking drivers must call dev_kfree_skb to free the socket buffer

and return NETDEV_TX_OK if the DMA mapping fails on the transmit hook

(ndo_start_xmit). This means that the socket buffer is just dropped in

the failure case.

SCSI drivers must return SCSI_MLQUEUE_HOST_BUSY if the DMA mapping

fails in the queuecommand hook. This means that the SCSI subsystem

passes the command to the driver again later.

		Optimizing Unmap State Space Consumption

On many platforms, dma_unmap_{single,page}() is simply a nop.

1) Struct scatterlist requirements.

   Struct scatterlist must contain, at a minimum, the following

   members:

	struct page *page;

	unsigned int offset;

	unsigned int length;

   The base address is specified by a "page+offset" pair.

   Previous versions of struct scatterlist contained a "void *address"

   field that was sometimes used instead of page+offset.  As of Linux

   2.5., page+offset is always used, and the "address" field has been

   deleted.

2) More to come...

			Handling Errors

DMA address space is limited on some architectures and an allocation

failure can be determined by:

- checking if dma_alloc_coherent returns NULL or dma_map_sg returns 0

- checking the returned dma_addr_t of dma_map_single and dma_map_page

  by using dma_mapping_error():

	dma_addr_t dma_handle;

	dma_handle = dma_map_single(dev, addr, size, direction);

	if (dma_mapping_error(dev, dma_handle)) {

		/*

		 * reduce current DMA mapping usage,

		 * delay and try again later or

		 * reset driver.

		 */

	}

   Don't invent the architecture specific struct scatterlist; just use

   <asm-generic/scatterlist.h>. You need to enable

   CONFIG_NEED_SG_DMA_LENGTH if the architecture supports IOMMUs

   (including software IOMMU).

2) ARCH_KMALLOC_MINALIGN

   Architectures must ensure that kmalloc'ed buffer is

   DMA-safe. Drivers and subsystems depend on it. If an architecture

   isn't fully DMA-coherent (i.e. hardware doesn't ensure that data in

   the CPU cache is identical to data in main memory),

   ARCH_KMALLOC_MINALIGN must be set so that the memory allocator

   makes sure that kmalloc'ed buffer doesn't share a cache line with

   the others. See arch/arm/include/asm/cache.h as an example.

   Note that ARCH_KMALLOC_MINALIGN is about DMA memory alignment

   constraints. You don't need to worry about the architecture data

   alignment constraints (e.g. the alignment constraints about 64-bit

   objects).

			   Closing

			information about the device.

		</para>

		<programlisting>

int __init board_init (void)

static int __init board_init (void)

{

	struct nand_chip *this;

	int err = 0;