[PATCH 04/14] ARM: OMAP2+: Add function for configuring GPMC settings

[Philip, Avinash]

On Tue, Feb 26, 2013 at 23:00:31, Hunter, Jon wrote:
> The GPMC has various different configuration options such as bus-width,
> synchronous or asychronous mode selection, burst mode options etc.
> Currently, there is no common function for configuring these options and
> various devices set these options by either programming the GPMC CONFIG1
> register directly or by calling gpmc_cs_configure() to set some of the
> options.
> 
> Add a new function for configuring all of the GPMC options. Having a common
> function for configuring this options will simplify code and ease the
> migration to device-tree.
> 
> Signed-off-by: Jon Hunter <jon-hunter at ti.com>
> ---
>  arch/arm/mach-omap2/gpmc.c |   65 ++++++++++++++++++++++++++++++++++++++++++++
>  arch/arm/mach-omap2/gpmc.h |    6 ++++
>  2 files changed, 71 insertions(+)
> 
> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> index 465cac9..fb8dfd2 100644
> --- a/arch/arm/mach-omap2/gpmc.c
> +++ b/arch/arm/mach-omap2/gpmc.c
> @@ -1137,6 +1137,71 @@ int gpmc_calc_timings(struct gpmc_timings *gpmc_t,
>  	return 0;
>  }
>  
> +int gpmc_cs_program_settings(int cs, struct gpmc_settings *p)
> +{
> +	u32 config1;
> +
> +	if ((!p->device_width) || (p->device_width > GPMC_DEVWIDTH_16BIT)) {
> +		pr_err("%s: invalid width %d!", __func__, p->device_width);
> +		return -EINVAL;
> +	}
> +
> +	/* Address-data multiplexing not supported for NAND devices */
> +	if (p->device_nand && p->mux_add_data) {
> +		pr_err("%s: invalid configuration!\n", __func__);
> +		return -EINVAL;
> +	}
> +
> +	/* Page/burst mode supports lengths of 4, 8 and 16 bytes */
> +	if (p->burst_read || p->burst_write) {
> +		switch (p->burst_len) {
> +		case GPMC_BURST_4:
> +		case GPMC_BURST_8:
> +		case GPMC_BURST_16:
> +			break;
> +		default:
> +			pr_err("%s: invalid page/burst-length (%d)\n",
> +			       __func__, p->burst_len);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	if ((p->wait_on_read || p->wait_on_write) &&
> +	    (p->wait_pin > gpmc_nr_waitpins)) {
> +		pr_err("%s: invalid wait-pin (%d)\n", __func__, p->wait_pin);
> +		return -EINVAL;
> +	}
> +
> +	config1 = GPMC_CONFIG1_DEVICESIZE((p->device_width - 1));

Can you consider read_modify approach?
Thanks
Avinash