Re: [PATCH v3 1/6] memory: omap-gpmc: Store handle to GPMC dev

Franklin S Cooper Jr.
2016-03-10T13:40:59Z

On 03/10/2016 06:40 AM, Roger Quadros wrote:
> Franklin,
>
> On 10/03/16 06:07, Franklin S Cooper Jr wrote:
>> The dma channel information is located within the GPMC node. The NAND
>> driver requires a handle to the GPMC's dev to properly parse the DMA
>> properties. Therefore, store a handle to the dev so it can be referenced
>> within the NAND driver.
>>
>> Signed-off-by: Franklin S Cooper Jr <fcooper@ti.com>
>> ---
>> drivers/memory/omap-gpmc.c | 1 +
>> include/linux/platform_data/mtd-nand-omap2.h | 2 ++
>> 2 files changed, 3 insertions(+)
>>
>> diff --git a/drivers/memory/omap-gpmc.c b/drivers/memory/omap-gpmc.c
>> index 6515dfc..2932d13 100644
>> --- a/drivers/memory/omap-gpmc.c
>> +++ b/drivers/memory/omap-gpmc.c
>> @@ -1796,6 +1796,7 @@ static int gpmc_probe_nand_child(struct platform_device *pdev,
>>
>> gpmc_nand_data->cs = val;
>> gpmc_nand_data->of_node = child;
>> + gpmc_nand_data->gpmc_dev = &pdev->dev;
>>
>> /* Detect availability of ELM module */
>> gpmc_nand_data->elm_of_node = of_parse_phandle(child, "ti,elm-id", 0);
>> diff --git a/include/linux/platform_data/mtd-nand-omap2.h b/include/linux/platform_data/mtd-nand-omap2.h
>> index 090bbab..534b984 100644
>> --- a/include/linux/platform_data/mtd-nand-omap2.h
>> +++ b/include/linux/platform_data/mtd-nand-omap2.h
>> @@ -80,5 +80,7 @@ struct omap_nand_platform_data {
>> /* for passing the partitions */
>> struct device_node *of_node;
>> struct device_node *elm_of_node;
>> +
>> + struct device *gpmc_dev;
>> };
>> #endif
>>
> Why do you need this? Can't we just use dev->parent in the omap2-nand driver?

The omap2-nand platform_device is created by
platform_device_alloc. The created platform_device dev
parent isn't by default set to the GPMC dev. I didn't think
this was the right approach to manually set the parent
property. However, taking a look at other usages of
platform_device_alloc it seems this is actually pretty
common. If your ok with this then I can go that route.
>
> cheers,
> -roger