[PATCH 1/2] cfa-10036: Use the second MMC partition to store the environment

[Eric Bénard]

Hi Maxime,

Le Wed, 13 Feb 2013 17:45:17 +0100,
Maxime Ripard <maxime.ripard at free-electrons.com> a écrit :

> Since the only storage medium on the cfa-10036 is the MMC card, we need
> to have a registered environment partition on it if we want to be able
> to modify at runtime.
> 
maybe you could add :
code copied from imx23-olinuxino.c

Eric

> Signed-off-by: Maxime Ripard <maxime.ripard at free-electrons.com>
> ---
>  arch/arm/boards/crystalfontz-cfa10036/cfa10036.c |   44 +++++++++++++++++++++-
>  1 file changed, 43 insertions(+), 1 deletion(-)
> 
> diff --git a/arch/arm/boards/crystalfontz-cfa10036/cfa10036.c b/arch/arm/boards/crystalfontz-cfa10036/cfa10036.c
> index b59dbab..1821b10 100644
> --- a/arch/arm/boards/crystalfontz-cfa10036/cfa10036.c
> +++ b/arch/arm/boards/crystalfontz-cfa10036/cfa10036.c
> @@ -97,9 +97,46 @@ static int cfa10036_mem_init(void)
>  }
>  mem_initcall(cfa10036_mem_init);
>  
> +/**
> + * Try to register an environment storage on the attached MCI card
> + * @return 0 on success
> + *
> + * We rely on the existence of a usable SD card, already attached to
> + * our system, to get something like a persistent memory for our environment.
> + * If this SD card is also the boot media, we can use the second partition
> + * for our environment purpose (if present!).
> + */
> +static int register_persistant_environment(void)
> +{
> +	struct cdev *cdev;
> +
> +	/*
> +	 * The CFA-10036 only has one MCI card socket.
> +	 * So, we expect its name as "disk0".
> +	 */
> +	cdev = cdev_by_name("disk0");
> +	if (cdev == NULL) {
> +		pr_err("No SD card found\n");
> +		return -ENODEV;
> +	}
> +
> +	/* MCI card is present, also a useable partition on it? */
> +	cdev = cdev_by_name("disk0.1");
> +	if (cdev == NULL) {
> +		pr_err("No second partition available\n");
> +		pr_info("Please create at least a second partition with"
> +			" 256 kiB...512 kiB in size (your choice)\n");
> +		return -ENODEV;
> +	}
> +
> +	/* use the full partition as our persistent environment storage */
> +	return devfs_add_partition("disk0.1", 0, cdev->size,
> +						DEVFS_PARTITION_FIXED, "env0");
> +}
> +
>  static int cfa10036_devices_init(void)
>  {
> -	int i;
> +	int i, ret;
>  
>  	/* initizalize muxing */
>  	for (i = 0; i < ARRAY_SIZE(cfa10036_pads); i++)
> @@ -124,6 +161,11 @@ static int cfa10036_devices_init(void)
>  
>  	cfa10036_detect_hw();
>  
> +	ret = register_persistant_environment();
> +	if (ret != 0)
> +		printf("Cannot create the 'env0' persistant "
> +			 "environment storage (%d)\n", ret);
> +
>  	return 0;
>  }
>  device_initcall(cfa10036_devices_init);