/*
* linux/arch/arm/plat-pxa/mfp.c
*
* Multi-Function Pin Support
*
* Copyright (C) 2007 Marvell Internation Ltd.
*
* 2007-08-21: eric miao <eric.miao@marvell.com>
* initial version
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <plat/mfp.h>
#define MFPR_SIZE (PAGE_SIZE)
/* MFPR register bit definitions */
#define MFPR_PULL_SEL (0x1 << 15)
#define MFPR_PULLUP_EN (0x1 << 14)
#define MFPR_PULLDOWN_EN (0x1 << 13)
#define MFPR_SLEEP_SEL (0x1 << 9)
#define MFPR_SLEEP_OE_N (0x1 << 7)
#define MFPR_EDGE_CLEAR (0x1 << 6)
#define MFPR_EDGE_FALL_EN (0x1 << 5)
#define MFPR_EDGE_RISE_EN (0x1 << 4)
#define MFPR_SLEEP_DATA(x) ((x) << 8)
#define MFPR_DRIVE(x) (((x) & 0x7) << 10)
#define MFPR_AF_SEL(x) (((x) & 0x7) << 0)
#define MFPR_EDGE_NONE (0)
#define MFPR_EDGE_RISE (MFPR_EDGE_RISE_EN)
#define MFPR_EDGE_FALL (MFPR_EDGE_FALL_EN)
#define MFPR_EDGE_BOTH (MFPR_EDGE_RISE | MFPR_EDGE_FALL)
/*
* Table that determines the low power modes outputs, with actual settings
* used in parentheses for don't-care values. Except for the float output,
* the configured driven and pulled levels match, so if there is a need for
* non-LPM pulled output, the same configuration could probably be used.
*
* Output value sleep_oe_n sleep_data pullup_en pulldown_en pull_sel
* (bit 7) (bit 8) (bit 14) (bit 13) (bit 15)
*
* Input 0 X(0) X(0) X(0) 0
* Drive 0 0 0 0 X(1) 0
* Drive 1 0 1 X(1) 0 0
* Pull hi (1) 1 X(1) 1 0 0
* Pull lo (0) 1 X(0) 0 1 0
* Z (float) 1 X(0) 0 0 0
*/
#define MFPR_LPM_INPUT (0)
#define MFPR_LPM_DRIVE_LOW (MFPR_SLEEP_DATA(0) | MFPR_PULLDOWN_EN)
#define MFPR_LPM_DRIVE_HIGH (MFPR_SLEEP_DATA(1) | MFPR_PULLUP_EN)
#define MFPR_LPM_PULL_LOW (MFPR_LPM_DRIVE_LOW | MFPR_SLEEP_OE_N)
#define MFPR_LPM_PULL_HIGH (MFPR_LPM_DRIVE_HIGH | MFPR_SLEEP_OE_N)
#define MFPR_LPM_FLOAT (MFPR_SLEEP_OE_N)
#define MFPR_LPM_MASK (0xe080)
/*
* The pullup and pulldown state of the MFP pin at run mode is by default
* determined by the selected alternate function. In case that some buggy
* devices need to override this default behavior, the definitions below
* indicates the setting of corresponding MFPR bits
*
* Definition pull_sel pullup_en pulldown_en
* MFPR_PULL_NONE 0 0 0
* MFPR_PULL_LOW 1 0 1
* MFPR_PULL_HIGH 1 1 0
* MFPR_PULL_BOTH 1 1 1
* MFPR_PULL_FLOAT 1 0 0
*/
#define MFPR_PULL_NONE (0)
#define MFPR_PULL_LOW (MFPR_PULL_SEL | MFPR_PULLDOWN_EN)
#define MFPR_PULL_BOTH (MFPR_PULL_LOW | MFPR_PULLUP_EN)
#define MFPR_PULL_HIGH (MFPR_PULL_SEL | MFPR_PULLUP_EN)
#define MFPR_PULL_FLOAT (MFPR_PULL_SEL)
/* mfp_spin_lock is used to ensure that MFP register configuration
* (most likely a read-modify-write operation) is atomic, and that
* mfp_table[] is consistent
*/
static DEFINE_SPINLOCK(mfp_spin_lock);
static void __iomem *mfpr_mmio_base;
struct mfp_pin {
unsigned long config; /* -1 for not configured */
unsigned long mfpr_off; /* MFPRxx Register offset */
unsigned long mfpr_run; /* Run-Mode Register Value */
unsigned long mfpr_lpm; /* Low Power Mode Register Value */
};
static struct mfp_pin mfp_table[MFP_PIN_MAX];
/* mapping of MFP_LPM_* definitions to MFPR_LPM_* register bits */
static const unsigned long mfpr_lpm[] = {
MFPR_LPM_INPUT,
MFPR_LPM_DRIVE_LOW,
MFPR_LPM_DRIVE_HIGH,
MFPR_LPM_PULL_LOW,
MFPR_LPM_PULL_HIGH,
MFPR_LPM_FLOAT,
MFPR_LPM_INPUT,
};
/* mapping of MFP_PULL_* definitions to MFPR_PULL_* register bits */
static const unsigned long mfpr_pull[] = {
MFPR_PULL_NONE,
MFPR_PULL_LOW,
MFPR_PULL_HIGH,
MFPR_PULL_BOTH,
MFPR_PULL_FLOAT,
};
/* mapping of MFP_LPM_EDGE_* definitions to MFPR_EDGE_* register bits */
static const unsigned long mfpr_edge[] = {
MFPR_EDGE_NONE,
MFPR_EDGE_RISE,
MFPR_EDGE_FALL,
MFPR_EDGE_BOTH,
};
#define mfpr_readl(off) \
__raw_readl(mfpr_mmio_base + (off))
#define mfpr_writel(off, val) \
__raw_writel(val, mfpr_mmio_base + (off))
#define mfp_configured(p) ((p)->config != -1)
/*
* perform a read-back of any valid MFPR register to make sure the
* previous writings are finished
*/
static unsigned long mfpr_off_readback;
#define mfpr_sync() (void)__raw_readl(mfpr_mmio_base + mfpr_off_readback)
static inline void __mfp_config_run(struct mfp_pin *p)
{
if (mfp_configured(p))
mfpr_writel(p->mfpr_off, p->mfpr_run);
}
static inline void __mfp_config_lpm(struct mfp_pin *p)
{
if (mfp_configured(p)) {
unsigned long mfpr_clr = (p->mfpr_run & ~MFPR_EDGE_BOTH) | MFPR_EDGE_CLEAR;
if (mfpr_clr != p->mfpr_run)
mfpr_writel(p->mfpr_off, mfpr_clr);
if (p->mfpr_lpm != mfpr_clr)
mfpr_writel(p->mfpr_off, p->mfpr_lpm);
}
}
void mfp_config(unsigned long *mfp_cfgs, int num)
{
unsigned long flags;
int i;
spin_lock_irqsave(&mfp_spin_lock, flags);
for (i = 0; i < num; i++, mfp_cfgs++) {
unsigned long tmp, c = *mfp_cfgs;
struct mfp_pin *p;
int pin, af, drv, lpm, edge, pull;
pin = MFP_PIN(c);
BUG_ON(pin >= MFP_PIN_MAX);
p = &mfp_table[pin];
af = MFP_AF(c);
drv = MFP_DS(c);
lpm = MFP_LPM_STATE(c);
edge = MFP_LPM_EDGE(c);
pull = MFP_PULL(c);
/* run-mode pull settings will conflict with MFPR bits of
* low power mode state, calculate mfpr_run and mfpr_lpm
* individually if pull != MFP_PULL_NONE
*/
tmp = MFPR_AF_SEL(af) | MFPR_DRIVE(drv);
if (likely(pull == MFP_PULL_NONE)) {
p->mfpr_run = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
p->mfpr_lpm = p->mfpr_run;
} else {
p->mfpr_lpm = tmp | mfpr_lpm[lpm] | mfpr_edge[edge];
p->mfpr_run = tmp | mfpr_pull[pull];
}
p->config = c; __mfp_config_run(p);
}
mfpr_sync();
spin_unlock_irqrestore(&mfp_spin_lock, flags);
}
unsigned long mfp_read(int mfp)
{
unsigned long val, flags;
BUG_ON(mfp < 0 || mfp >= MFP_PIN_MAX);
spin_lock_irqsave(&mfp_spin_lock, flags);
val = mfpr_readl(mfp_table[mfp].mfpr_off);
spin_unlock_irqrestore(&mfp_spin_lock, flags);
return val;
}
void mfp_write(int mfp, unsigned long val)
{
unsigned long flags;
BUG_ON(mfp < 0 || mfp >= MFP_PIN_MAX);
spin_lock_irqsave(&mfp_spin_lock, flags);
mfpr_writel(mfp_table[mfp].mfpr_off, val);
mfpr_sync();
spin_unlock_irqrestore(&mfp_spin_lock, flags);
}
void __init mfp_init_base(void __iomem *mfpr_base)
{
int i;
/* initialize the table with default - unconfigured */
for (i = 0; i < ARRAY_SIZE(mfp_table); i++)
mfp_table[i].config = -1;
mfpr_mmio_base = mfpr_base;
}
void __init mfp_init_addr(struct mfp_addr_map *map)
{
struct mfp_addr_map *p;
unsigned long offset, flags;
int i;
spin_lock_irqsave(&mfp_spin_lock, flags);
/* mfp offset for readback */
mfpr_off_readback = map[0].offset;
for (p = map; p->start != MFP_PIN_INVALID; p++) {
offset = p->offset;
i = p->start;
do {
mfp_table[i].mfpr_off = offset;
mfp_table[i].mfpr_run = 0;
mfp_table[i].mfpr_lpm = 0;
offset += 4; i++;
} while ((i <= p->end) && (p->end != -1));
}
spin_unlock_irqrestore(&mfp_spin_lock, flags);
}
void mfp_config_lpm(void)
{
struct mfp_pin *p = &mfp_table[0];
int pin;
for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++, p++)
__mfp_config_lpm(p);
}
void mfp_config_run(void)
{
struct mfp_pin *p = &mfp_table[0];
int pin;
for (pin = 0; pin < ARRAY_SIZE(mfp_table); pin++, p++)
__mfp_config_run(p);
}
