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Commit 496c8a0b authored by Mark Jackson's avatar Mark Jackson Committed by Tony Lindgren
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ARM: OMAP2+: Allow NAND transfer mode to be specified in DT 



OMAP devices support various NAND transfer modes.

Currently all device-tree definitions will use the default "prefetch
polled" mode, so this patch enables the transfer mode to be specified
in the device-tree.

Signed-off-by: default avatarMark Jackson <mpfj@newflow.co.uk>
Acked-by: default avatarPekon Gupta <pekon@ti.com>
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
parent 4d584361

Documentation/devicetree/bindings/mtd/gpmc-nand.txt

+8 −0
Original line number Diff line number Diff line
@@ -29,6 +29,13 @@ Optional properties: 
		"bch4"		4-bit BCH ecc code

		"bch8"		8-bit BCH ecc code



 - ti,nand-xfer-type:		A string setting the data transfer type. One of:



		"prefetch-polled"	Prefetch polled mode (default)

		"polled"		Polled mode, without prefetch

		"prefetch-dma"		Prefetch enabled sDMA mode

		"prefetch-irq"		Prefetch enabled irq mode



 - elm_id:	Specifies elm device node. This is required to support BCH

 		error correction using ELM module.
@@ -55,6 +62,7 @@ Example for an AM33xx board: 
			reg = <0 0 0>; /* CS0, offset 0 */

			nand-bus-width = <16>;

			ti,nand-ecc-opt = "bch8";

			ti,nand-xfer-type = "polled";



			gpmc,sync-clk-ps = <0>;

			gpmc,cs-on-ns = <0>;

arch/arm/mach-omap2/gpmc.c

+14 −0
Original line number Diff line number Diff line
@@ -1345,6 +1345,13 @@ static const char * const nand_ecc_opts[] = { 
	[OMAP_ECC_BCH8_CODE_HW]			= "bch8",

};



static const char * const nand_xfer_types[] = {

	[NAND_OMAP_PREFETCH_POLLED]		= "prefetch-polled",

	[NAND_OMAP_POLLED]			= "polled",

	[NAND_OMAP_PREFETCH_DMA]		= "prefetch-dma",

	[NAND_OMAP_PREFETCH_IRQ]		= "prefetch-irq",

};



static int gpmc_probe_nand_child(struct platform_device *pdev,

				 struct device_node *child)

{
@@ -1374,6 +1381,13 @@ static int gpmc_probe_nand_child(struct platform_device *pdev, 
				break;

			}



	if (!of_property_read_string(child, "ti,nand-xfer-type", &s))

		for (val = 0; val < ARRAY_SIZE(nand_xfer_types); val++)

			if (!strcasecmp(s, nand_xfer_types[val])) {

				gpmc_nand_data->xfer_type = val;

				break;

			}



	val = of_get_nand_bus_width(child);

	if (val == 16)

		gpmc_nand_data->devsize = NAND_BUSWIDTH_16;