[PATCH V3 02/18] ARM: OMAP2+: Add variable to store number of GPMC waitpins
From: Jon Hunter <hidden>
Date: 2013-03-15 15:21:00
Also in:
linux-devicetree, linux-omap
Subsystem:
arm port, omap general purpose memory controller support, omap power management support, omap2+ support, the rest · Maintainers:
Russell King, Roger Quadros, Tony Lindgren, Kevin Hilman, Aaro Koskinen, Andreas Kemnade, Linus Torvalds
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 <redacted> --- 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; + + 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);
--
1.7.10.4