diff options
author | Jon Hunter <jon-hunter@ti.com> | 2013-02-21 01:53:38 +0400 |
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committer | Jon Hunter <jon-hunter@ti.com> | 2013-04-01 23:53:40 +0400 |
commit | 9f8331562aa1fd72e80dd6037c958cb3faf4cc38 (patch) | |
tree | d1989fd4b4ec933b36f5645948094e31d51c0e13 /arch/arm/mach-omap2/gpmc.c | |
parent | be9f10c04fb13d32fc30d599c1971a10916a2209 (diff) | |
download | linux-9f8331562aa1fd72e80dd6037c958cb3faf4cc38.tar.xz |
ARM: OMAP2+: Add variable to store number of GPMC waitpins
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@ti.com>
Tested-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Diffstat (limited to 'arch/arm/mach-omap2/gpmc.c')
-rw-r--r-- | arch/arm/mach-omap2/gpmc.c | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/gpmc.c b/arch/arm/mach-omap2/gpmc.c index 586dba7e5f23..8833c349f23c 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; @@ -1294,6 +1297,13 @@ 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 +1382,9 @@ static int gpmc_probe(struct platform_device *pdev) /* Now the GPMC is initialised, unreserve the chip-selects */ gpmc_cs_map = 0; + if (!pdev->dev.of_node) + gpmc_nr_waitpins = GPMC_NR_WAITPINS; + rc = gpmc_probe_dt(pdev); if (rc < 0) { clk_disable_unprepare(gpmc_l3_clk); |