arch/arm/mach-omap1/mux.c

Source file repositories/reference/linux-study-clean/arch/arm/mach-omap1/mux.c

File Facts

System
Linux kernel
Corpus path
arch/arm/mach-omap1/mux.c
Extension
.c
Size
18973 bytes
Lines
460
Domain
Architecture Layer
Bucket
arch/arm
Inferred role
Architecture Layer: exported/initcall integration point
Status
integration implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

if (cfg->pu_pd_reg && cfg->pull_val) {
			spin_lock_irqsave(&mux_spin_lock, flags);
			pu_pd_orig = omap_readl(cfg->pu_pd_reg);
			mask = 1 << cfg->pull_bit;

			if (cfg->pu_pd_val) {
				if (!(pu_pd_orig & mask))
					warn = 1;
				/* Use pull up */
				pu_pd = pu_pd_orig | mask;
			} else {
				if (pu_pd_orig & mask)
					warn = 1;
				/* Use pull down */
				pu_pd = pu_pd_orig & ~mask;
			}
			omap_writel(pu_pd, cfg->pu_pd_reg);
			spin_unlock_irqrestore(&mux_spin_lock, flags);
		}
	}

	/* Check for an associated pull down register */
	if (cfg->pull_reg) {
		spin_lock_irqsave(&mux_spin_lock, flags);
		pull_orig = omap_readl(cfg->pull_reg);
		mask = 1 << cfg->pull_bit;

		if (cfg->pull_val) {
			if (pull_orig & mask)
				warn = 1;
			/* Low bit = pull enabled */
			pull = pull_orig & ~mask;
		} else {
			if (!(pull_orig & mask))
				warn = 1;
			/* High bit = pull disabled */
			pull = pull_orig | mask;
		}

		omap_writel(pull, cfg->pull_reg);
		spin_unlock_irqrestore(&mux_spin_lock, flags);
	}

	if (warn) {
#ifdef CONFIG_OMAP_MUX_WARNINGS
		printk(KERN_WARNING "MUX: initialized %s\n", cfg->name);
#endif
	}

#ifdef CONFIG_OMAP_MUX_DEBUG
	if (cfg->debug || warn) {
		printk("MUX: Setting register %s\n", cfg->name);
		printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
		       cfg->mux_reg_name, cfg->mux_reg, reg_orig, reg);

		if (!cpu_is_omap15xx()) {
			if (cfg->pu_pd_reg && cfg->pull_val) {
				printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
				       cfg->pu_pd_name, cfg->pu_pd_reg,
				       pu_pd_orig, pu_pd);
			}
		}

		if (cfg->pull_reg)
			printk("      %s (0x%08x) = 0x%08x -> 0x%08x\n",
			       cfg->pull_name, cfg->pull_reg, pull_orig, pull);
	}
#endif

#ifdef CONFIG_OMAP_MUX_WARNINGS
	return warn ? -ETXTBSY : 0;
#else
	return 0;
#endif
}

static struct omap_mux_cfg *mux_cfg;

int __init omap_mux_register(struct omap_mux_cfg *arch_mux_cfg)
{
	if (!arch_mux_cfg || !arch_mux_cfg->pins || arch_mux_cfg->size == 0
			|| !arch_mux_cfg->cfg_reg) {
		printk(KERN_ERR "Invalid pin table\n");
		return -EINVAL;
	}

	mux_cfg = arch_mux_cfg;

	return 0;
}

Annotation

Implementation Notes