linux-zen-server/arch/arm/mach-davinci/mux.c

100 lines
2.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Utility to set the DAVINCI MUX register from a table in mux.h
*
* Author: Vladimir Barinov, MontaVista Software, Inc. <source@mvista.com>
*
* Based on linux/arch/arm/plat-omap/mux.c:
* Copyright (C) 2003 - 2005 Nokia Corporation
*
* Written by Tony Lindgren
*
* 2007 (c) MontaVista Software, Inc.
*
* Copyright (C) 2008 Texas Instruments.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/io.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include "mux.h"
#include "common.h"
static void __iomem *pinmux_base;
/*
* Sets the DAVINCI MUX register based on the table
*/
int davinci_cfg_reg(const unsigned long index)
{
static DEFINE_SPINLOCK(mux_spin_lock);
struct davinci_soc_info *soc_info = &davinci_soc_info;
unsigned long flags;
const struct mux_config *cfg;
unsigned int reg_orig = 0, reg = 0;
unsigned int mask, warn = 0;
if (WARN_ON(!soc_info->pinmux_pins))
return -ENODEV;
if (!pinmux_base) {
pinmux_base = ioremap(soc_info->pinmux_base, SZ_4K);
if (WARN_ON(!pinmux_base))
return -ENOMEM;
}
if (index >= soc_info->pinmux_pins_num) {
pr_err("Invalid pin mux index: %lu (%lu)\n",
index, soc_info->pinmux_pins_num);
dump_stack();
return -ENODEV;
}
cfg = &soc_info->pinmux_pins[index];
if (cfg->name == NULL) {
pr_err("No entry for the specified index\n");
return -ENODEV;
}
/* Update the mux register in question */
if (cfg->mask) {
unsigned tmp1, tmp2;
spin_lock_irqsave(&mux_spin_lock, flags);
reg_orig = __raw_readl(pinmux_base + cfg->mux_reg);
mask = (cfg->mask << cfg->mask_offset);
tmp1 = reg_orig & mask;
reg = reg_orig & ~mask;
tmp2 = (cfg->mode << cfg->mask_offset);
reg |= tmp2;
if (tmp1 != tmp2)
warn = 1;
__raw_writel(reg, pinmux_base + cfg->mux_reg);
spin_unlock_irqrestore(&mux_spin_lock, flags);
}
if (warn) {
#ifdef CONFIG_DAVINCI_MUX_WARNINGS
pr_warn("initialized %s\n", cfg->name);
#endif
}
#ifdef CONFIG_DAVINCI_MUX_DEBUG
if (cfg->debug || warn) {
pr_warn("Setting register %s\n", cfg->name);
pr_warn(" %s (0x%08x) = 0x%08x -> 0x%08x\n",
cfg->mux_reg_name, cfg->mux_reg, reg_orig, reg);
}
#endif
return 0;
}