[PATCH v3 3/3] arm: omap2: gpmc: add DT bindings for OneNAND

Mark Rutland mark.rutland at arm.com
Fri Jan 25 10:56:33 EST 2013


Hi,

I have a couple more comments after looking though this a bit more thoroughly.

On Fri, Jan 25, 2013 at 12:23:11PM +0000, Ezequiel Garcia wrote:
> This patch adds device tree bindings for OMAP OneNAND devices.
> Tested on an OMAP3 3430 IGEPv2 board.
> 
> Signed-off-by: Ezequiel Garcia <ezequiel.garcia at free-electrons.com>
> ---
> Changes from v2:
>  * Remove unneeded of_node_put() as reported by Mark Rutland
> 
> Changes from v1:
>  * Fix typo in Documentation/devicetree/bindings/mtd/gpmc-onenand.txt
> 
>  .../devicetree/bindings/mtd/gpmc-onenand.txt       |   43 +++++++++++++++++++
>  arch/arm/mach-omap2/gpmc.c                         |   45 ++++++++++++++++++++
>  2 files changed, 88 insertions(+), 0 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/mtd/gpmc-onenand.txt
> 
> diff --git a/Documentation/devicetree/bindings/mtd/gpmc-onenand.txt b/Documentation/devicetree/bindings/mtd/gpmc-onenand.txt
> new file mode 100644
> index 0000000..deec9da
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/gpmc-onenand.txt
> @@ -0,0 +1,43 @@
> +Device tree bindings for GPMC connected OneNANDs
> +
> +GPMC connected OneNAND (found on OMAP boards) are represented as child nodes of
> +the GPMC controller with a name of "onenand".
> +
> +All timing relevant properties as well as generic gpmc child properties are
> +explained in a separate documents - please refer to
> +Documentation/devicetree/bindings/bus/ti-gpmc.txt

Which tree can I find this in?

> +
> +Required properties:
> +
> + - reg:			The CS line the peripheral is connected to
> +
> +Optional properties:
> +
> + - dma-channel:		DMA Channel index
> +
> +For inline partiton table parsing (optional):
> +
> + - #address-cells: should be set to 1
> + - #size-cells: should be set to 1
> +
> +Example for an OMAP3430 board:
> +
> +	gpmc: gpmc at 6e000000 {
> +		compatible = "ti,omap3430-gpmc";
> +		ti,hwmods = "gpmc";
> +		reg = <0x6e000000 0x1000000>;
> +		interrupts = <20>;
> +		gpmc,num-cs = <8>;
> +		gpmc,num-waitpins = <4>;
> +		#address-cells = <2>;
> +		#size-cells = <1>;
> +
> +		onenand at 0 {
> +			reg = <0 0 0>; /* CS0, offset 0 */
> +
> +			#address-cells = <1>;
> +			#size-cells = <1>;
> +
> +			/* partitions go here */
> +		};
> +	};
> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> index c6255f7..0636d0a 100644
> --- a/arch/arm/mach-omap2/gpmc.c
> +++ b/arch/arm/mach-omap2/gpmc.c
> @@ -39,6 +39,7 @@
>  #include "omap_device.h"
>  #include "gpmc.h"
>  #include "gpmc-nand.h"
> +#include "gpmc-onenand.h"
>  
>  #define	DEVICE_NAME		"omap-gpmc"
>  
> @@ -1259,6 +1260,43 @@ static int gpmc_probe_nand_child(struct platform_device *pdev,
>  }
>  #endif
>  
> +#ifdef CONFIG_MTD_ONENAND
> +static int gpmc_probe_onenand_child(struct platform_device *pdev,
> +				 struct device_node *child)
> +{
> +	u32 val;
> +	struct omap_onenand_platform_data *gpmc_onenand_data;
> +
> +	if (of_property_read_u32(child, "reg", &val) < 0) {
> +		dev_err(&pdev->dev, "%s has no 'reg' property\n",
> +			child->full_name);
> +		return -ENODEV;
> +	}

I don't understand the format of the reg property, but it seems odd that you
only need to read one cell from it. Are the remaining address cell and size
cell used anywhere?

> +
> +	gpmc_onenand_data = devm_kzalloc(&pdev->dev, sizeof(*gpmc_onenand_data),
> +					 GFP_KERNEL);
> +	if (!gpmc_onenand_data)
> +		return -ENOMEM;
> +
> +	gpmc_onenand_data->cs = val;
> +	gpmc_onenand_data->of_node = child;
> +	gpmc_onenand_data->dma_channel = -1;
> +
> +	if (!of_property_read_u32(child, "dma-channel", &val))
> +		gpmc_onenand_data->dma_channel = val;
> +
> +	gpmc_onenand_init(gpmc_onenand_data);
> +
> +	return 0;
> +}

[...]

Otherwise looks good.

Thanks,
Mark.





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