Subject: [PATCH V3 02/18] ARM: OMAP2+: Add variable to store number of GPMC waitpins

From: [email-masked] (Ezequiel Garcia)
Date: Sat, 16 Mar 2013 17:59:17 -0300

Hi Jon,

On Fri, Mar 15, 2013 at 10:21:00AM -0500, Jon Hunter wrote:
> The GPMC has wait-pin signals that can be assigned to a chip-select
> to monitor the ready signal of an external device. Add a variable to
> indicate the total number of wait-pins for a given device. This will
> allow us to detect if the wait-pin being selected is valid or not.
> 
> When booting with device-tree read the number of wait-pins from the
> device-tree blob. When device-tree is not used set the number of
> wait-pins to 4 which is valid for OMAP2-5 devices. Newer devices
> that have less wait-pins (such as AM335x) only support booting with
> device-tree and so hard-coding the wait-pin number when not using
> device-tree is fine.
> 
> Signed-off-by: Jon Hunter <[email-masked]>
> ---
>  arch/arm/mach-omap2/gpmc.c |   16 ++++++++++++++++
>  1 file changed, 16 insertions(+)
> 
> diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c
> index ef655d9..88a261c 100644
> --- a/arch/arm/mach-omap2/gpmc.c
> +++ b/arch/arm/mach-omap2/gpmc.c
> @@ -108,6 +108,8 @@
>  #define	GPMC_HAS_WR_ACCESS		0x1
>  #define	GPMC_HAS_WR_DATA_MUX_BUS	0x2
>  
> +#define GPMC_NR_WAITPINS		4
> +
>  /* XXX: Only NAND irq has been considered,currently these are the only ones used
>   */
>  #define	GPMC_NR_IRQ		2
> @@ -153,6 +155,7 @@ static struct resource	gpmc_cs_mem[GPMC_CS_NUM];
>  static DEFINE_SPINLOCK(gpmc_mem_lock);
>  /* Define chip-selects as reserved by default until probe completes */
>  static unsigned int gpmc_cs_map = ((1 << GPMC_CS_NUM) - 1);
> +static unsigned int gpmc_nr_waitpins;
>  static struct device *gpmc_dev;
>  static int gpmc_irq;
>  static resource_size_t phys_base, mem_size;
> @@ -1297,6 +1300,13 @@ static int gpmc_probe_dt(struct platform_device *pdev)
>  	if (!of_id)
>  		return 0;
>  
> +	ret = of_property_read_u32(pdev->dev.of_node, "gpmc,num-waitpins",
> +				   &gpmc_nr_waitpins);
> +	if (ret < 0) {
> +		pr_err("%s: number of wait pins not found!\n", __func__);
> +		return ret;
> +	}
> +
>  	for_each_node_by_name(child, "nand") {
>  		ret = gpmc_probe_nand_child(pdev, child);
>  		if (ret < 0) {
> @@ -1372,6 +1382,12 @@ static int gpmc_probe(struct platform_device *pdev)
>  	if (gpmc_setup_irq() < 0)
>  		dev_warn(gpmc_dev, "gpmc_setup_irq failed\n");
>  
> +	/* Now the GPMC is initialised, unreserve the chip-selects */
> +	gpmc_cs_map = 0;

The above seems to be a remanent of another patch.
I think you already sent that one, right?

-- 
Ezequiel Garc?a, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com