[PATCH V3 02/18] ARM: OMAP2+: Add variable to store number of GPMC waitpins
Ezequiel Garcia
ezequiel.garcia at free-electrons.com
Sat Mar 16 16:59:17 EDT 2013
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 <jon-hunter at ti.com>
> ---
> 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 García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com
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