linux/arch/sh/kernel/gpio.c
Magnus Damm 69edbba002 sh: use gpiolib
This patch updates the SuperH gpio code to make use of gpiolib. The
gpiolib callbacks get() and set() are lockless, but we use our own
spinlock for the other operations to make sure hardware register
bitfield accesses stay atomic.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-01-27 14:49:10 +09:00

584 lines
12 KiB
C

/*
* Pinmuxed GPIO support for SuperH.
*
* Copyright (C) 2008 Magnus Damm
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/list.h>
#include <linux/module.h>
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/bitops.h>
#include <linux/gpio.h>
static int enum_in_range(pinmux_enum_t enum_id, struct pinmux_range *r)
{
if (enum_id < r->begin)
return 0;
if (enum_id > r->end)
return 0;
return 1;
}
static unsigned long gpio_read_raw_reg(unsigned long reg,
unsigned long reg_width)
{
switch (reg_width) {
case 8:
return ctrl_inb(reg);
case 16:
return ctrl_inw(reg);
case 32:
return ctrl_inl(reg);
}
BUG();
return 0;
}
static void gpio_write_raw_reg(unsigned long reg,
unsigned long reg_width,
unsigned long data)
{
switch (reg_width) {
case 8:
ctrl_outb(data, reg);
return;
case 16:
ctrl_outw(data, reg);
return;
case 32:
ctrl_outl(data, reg);
return;
}
BUG();
}
static void gpio_write_bit(struct pinmux_data_reg *dr,
unsigned long in_pos, unsigned long value)
{
unsigned long pos;
pos = dr->reg_width - (in_pos + 1);
#ifdef DEBUG
pr_info("write_bit addr = %lx, value = %ld, pos = %ld, "
"r_width = %ld\n",
dr->reg, !!value, pos, dr->reg_width);
#endif
if (value)
set_bit(pos, &dr->reg_shadow);
else
clear_bit(pos, &dr->reg_shadow);
gpio_write_raw_reg(dr->reg, dr->reg_width, dr->reg_shadow);
}
static int gpio_read_reg(unsigned long reg, unsigned long reg_width,
unsigned long field_width, unsigned long in_pos)
{
unsigned long data, mask, pos;
data = 0;
mask = (1 << field_width) - 1;
pos = reg_width - ((in_pos + 1) * field_width);
#ifdef DEBUG
pr_info("read_reg: addr = %lx, pos = %ld, "
"r_width = %ld, f_width = %ld\n",
reg, pos, reg_width, field_width);
#endif
data = gpio_read_raw_reg(reg, reg_width);
return (data >> pos) & mask;
}
static void gpio_write_reg(unsigned long reg, unsigned long reg_width,
unsigned long field_width, unsigned long in_pos,
unsigned long value)
{
unsigned long mask, pos;
mask = (1 << field_width) - 1;
pos = reg_width - ((in_pos + 1) * field_width);
#ifdef DEBUG
pr_info("write_reg addr = %lx, value = %ld, pos = %ld, "
"r_width = %ld, f_width = %ld\n",
reg, value, pos, reg_width, field_width);
#endif
mask = ~(mask << pos);
value = value << pos;
switch (reg_width) {
case 8:
ctrl_outb((ctrl_inb(reg) & mask) | value, reg);
break;
case 16:
ctrl_outw((ctrl_inw(reg) & mask) | value, reg);
break;
case 32:
ctrl_outl((ctrl_inl(reg) & mask) | value, reg);
break;
}
}
static int setup_data_reg(struct pinmux_info *gpioc, unsigned gpio)
{
struct pinmux_gpio *gpiop = &gpioc->gpios[gpio];
struct pinmux_data_reg *data_reg;
int k, n;
if (!enum_in_range(gpiop->enum_id, &gpioc->data))
return -1;
k = 0;
while (1) {
data_reg = gpioc->data_regs + k;
if (!data_reg->reg_width)
break;
for (n = 0; n < data_reg->reg_width; n++) {
if (data_reg->enum_ids[n] == gpiop->enum_id) {
gpiop->flags &= ~PINMUX_FLAG_DREG;
gpiop->flags |= (k << PINMUX_FLAG_DREG_SHIFT);
gpiop->flags &= ~PINMUX_FLAG_DBIT;
gpiop->flags |= (n << PINMUX_FLAG_DBIT_SHIFT);
return 0;
}
}
k++;
}
BUG();
return -1;
}
static void setup_data_regs(struct pinmux_info *gpioc)
{
struct pinmux_data_reg *drp;
int k;
for (k = gpioc->first_gpio; k <= gpioc->last_gpio; k++)
setup_data_reg(gpioc, k);
k = 0;
while (1) {
drp = gpioc->data_regs + k;
if (!drp->reg_width)
break;
drp->reg_shadow = gpio_read_raw_reg(drp->reg, drp->reg_width);
k++;
}
}
static int get_data_reg(struct pinmux_info *gpioc, unsigned gpio,
struct pinmux_data_reg **drp, int *bitp)
{
struct pinmux_gpio *gpiop = &gpioc->gpios[gpio];
int k, n;
if (!enum_in_range(gpiop->enum_id, &gpioc->data))
return -1;
k = (gpiop->flags & PINMUX_FLAG_DREG) >> PINMUX_FLAG_DREG_SHIFT;
n = (gpiop->flags & PINMUX_FLAG_DBIT) >> PINMUX_FLAG_DBIT_SHIFT;
*drp = gpioc->data_regs + k;
*bitp = n;
return 0;
}
static int get_config_reg(struct pinmux_info *gpioc, pinmux_enum_t enum_id,
struct pinmux_cfg_reg **crp, int *indexp,
unsigned long **cntp)
{
struct pinmux_cfg_reg *config_reg;
unsigned long r_width, f_width;
int k, n;
k = 0;
while (1) {
config_reg = gpioc->cfg_regs + k;
r_width = config_reg->reg_width;
f_width = config_reg->field_width;
if (!r_width)
break;
for (n = 0; n < (r_width / f_width) * 1 << f_width; n++) {
if (config_reg->enum_ids[n] == enum_id) {
*crp = config_reg;
*indexp = n;
*cntp = &config_reg->cnt[n / (1 << f_width)];
return 0;
}
}
k++;
}
return -1;
}
static int get_gpio_enum_id(struct pinmux_info *gpioc, unsigned gpio,
int pos, pinmux_enum_t *enum_idp)
{
pinmux_enum_t enum_id = gpioc->gpios[gpio].enum_id;
pinmux_enum_t *data = gpioc->gpio_data;
int k;
if (!enum_in_range(enum_id, &gpioc->data)) {
if (!enum_in_range(enum_id, &gpioc->mark)) {
pr_err("non data/mark enum_id for gpio %d\n", gpio);
return -1;
}
}
if (pos) {
*enum_idp = data[pos + 1];
return pos + 1;
}
for (k = 0; k < gpioc->gpio_data_size; k++) {
if (data[k] == enum_id) {
*enum_idp = data[k + 1];
return k + 1;
}
}
pr_err("cannot locate data/mark enum_id for gpio %d\n", gpio);
return -1;
}
static void write_config_reg(struct pinmux_info *gpioc,
struct pinmux_cfg_reg *crp,
int index)
{
unsigned long ncomb, pos, value;
ncomb = 1 << crp->field_width;
pos = index / ncomb;
value = index % ncomb;
gpio_write_reg(crp->reg, crp->reg_width, crp->field_width, pos, value);
}
static int check_config_reg(struct pinmux_info *gpioc,
struct pinmux_cfg_reg *crp,
int index)
{
unsigned long ncomb, pos, value;
ncomb = 1 << crp->field_width;
pos = index / ncomb;
value = index % ncomb;
if (gpio_read_reg(crp->reg, crp->reg_width,
crp->field_width, pos) == value)
return 0;
return -1;
}
enum { GPIO_CFG_DRYRUN, GPIO_CFG_REQ, GPIO_CFG_FREE };
static int pinmux_config_gpio(struct pinmux_info *gpioc, unsigned gpio,
int pinmux_type, int cfg_mode)
{
struct pinmux_cfg_reg *cr = NULL;
pinmux_enum_t enum_id;
struct pinmux_range *range;
int in_range, pos, index;
unsigned long *cntp;
switch (pinmux_type) {
case PINMUX_TYPE_FUNCTION:
range = NULL;
break;
case PINMUX_TYPE_OUTPUT:
range = &gpioc->output;
break;
case PINMUX_TYPE_INPUT:
range = &gpioc->input;
break;
case PINMUX_TYPE_INPUT_PULLUP:
range = &gpioc->input_pu;
break;
case PINMUX_TYPE_INPUT_PULLDOWN:
range = &gpioc->input_pd;
break;
default:
goto out_err;
}
pos = 0;
enum_id = 0;
index = 0;
while (1) {
pos = get_gpio_enum_id(gpioc, gpio, pos, &enum_id);
if (pos <= 0)
goto out_err;
if (!enum_id)
break;
in_range = enum_in_range(enum_id, &gpioc->function);
if (!in_range && range) {
in_range = enum_in_range(enum_id, range);
if (in_range && enum_id == range->force)
continue;
}
if (!in_range)
continue;
if (get_config_reg(gpioc, enum_id, &cr, &index, &cntp) != 0)
goto out_err;
switch (cfg_mode) {
case GPIO_CFG_DRYRUN:
if (!*cntp || !check_config_reg(gpioc, cr, index))
continue;
break;
case GPIO_CFG_REQ:
write_config_reg(gpioc, cr, index);
*cntp = *cntp + 1;
break;
case GPIO_CFG_FREE:
*cntp = *cntp - 1;
break;
}
}
return 0;
out_err:
return -1;
}
static DEFINE_SPINLOCK(gpio_lock);
static struct pinmux_info *chip_to_pinmux(struct gpio_chip *chip)
{
return container_of(chip, struct pinmux_info, chip);
}
static int sh_gpio_request(struct gpio_chip *chip, unsigned offset)
{
struct pinmux_info *gpioc = chip_to_pinmux(chip);
struct pinmux_data_reg *dummy;
unsigned long flags;
int i, ret, pinmux_type;
ret = -EINVAL;
if (!gpioc)
goto err_out;
spin_lock_irqsave(&gpio_lock, flags);
if ((gpioc->gpios[offset].flags & PINMUX_FLAG_TYPE) != PINMUX_TYPE_NONE)
goto err_unlock;
/* setup pin function here if no data is associated with pin */
if (get_data_reg(gpioc, offset, &dummy, &i) != 0)
pinmux_type = PINMUX_TYPE_FUNCTION;
else
pinmux_type = PINMUX_TYPE_GPIO;
if (pinmux_type == PINMUX_TYPE_FUNCTION) {
if (pinmux_config_gpio(gpioc, offset,
pinmux_type,
GPIO_CFG_DRYRUN) != 0)
goto err_unlock;
if (pinmux_config_gpio(gpioc, offset,
pinmux_type,
GPIO_CFG_REQ) != 0)
BUG();
}
gpioc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE;
gpioc->gpios[offset].flags |= pinmux_type;
ret = 0;
err_unlock:
spin_unlock_irqrestore(&gpio_lock, flags);
err_out:
return ret;
}
static void sh_gpio_free(struct gpio_chip *chip, unsigned offset)
{
struct pinmux_info *gpioc = chip_to_pinmux(chip);
unsigned long flags;
int pinmux_type;
if (!gpioc)
return;
spin_lock_irqsave(&gpio_lock, flags);
pinmux_type = gpioc->gpios[offset].flags & PINMUX_FLAG_TYPE;
pinmux_config_gpio(gpioc, offset, pinmux_type, GPIO_CFG_FREE);
gpioc->gpios[offset].flags &= ~PINMUX_FLAG_TYPE;
gpioc->gpios[offset].flags |= PINMUX_TYPE_NONE;
spin_unlock_irqrestore(&gpio_lock, flags);
}
static int pinmux_direction(struct pinmux_info *gpioc,
unsigned gpio, int new_pinmux_type)
{
int pinmux_type;
int ret = -EINVAL;
if (!gpioc)
goto err_out;
pinmux_type = gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE;
switch (pinmux_type) {
case PINMUX_TYPE_GPIO:
break;
case PINMUX_TYPE_OUTPUT:
case PINMUX_TYPE_INPUT:
case PINMUX_TYPE_INPUT_PULLUP:
case PINMUX_TYPE_INPUT_PULLDOWN:
pinmux_config_gpio(gpioc, gpio, pinmux_type, GPIO_CFG_FREE);
break;
default:
goto err_out;
}
if (pinmux_config_gpio(gpioc, gpio,
new_pinmux_type,
GPIO_CFG_DRYRUN) != 0)
goto err_out;
if (pinmux_config_gpio(gpioc, gpio,
new_pinmux_type,
GPIO_CFG_REQ) != 0)
BUG();
gpioc->gpios[gpio].flags &= ~PINMUX_FLAG_TYPE;
gpioc->gpios[gpio].flags |= new_pinmux_type;
ret = 0;
err_out:
return ret;
}
static int sh_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
{
struct pinmux_info *gpioc = chip_to_pinmux(chip);
unsigned long flags;
int ret;
spin_lock_irqsave(&gpio_lock, flags);
ret = pinmux_direction(gpioc, offset, PINMUX_TYPE_INPUT);
spin_unlock_irqrestore(&gpio_lock, flags);
return ret;
}
static void sh_gpio_set_value(struct pinmux_info *gpioc,
unsigned gpio, int value)
{
struct pinmux_data_reg *dr = NULL;
int bit = 0;
if (!gpioc || get_data_reg(gpioc, gpio, &dr, &bit) != 0)
BUG();
else
gpio_write_bit(dr, bit, value);
}
static int sh_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
int value)
{
struct pinmux_info *gpioc = chip_to_pinmux(chip);
unsigned long flags;
int ret;
sh_gpio_set_value(gpioc, offset, value);
spin_lock_irqsave(&gpio_lock, flags);
ret = pinmux_direction(gpioc, offset, PINMUX_TYPE_OUTPUT);
spin_unlock_irqrestore(&gpio_lock, flags);
return ret;
}
static int sh_gpio_get_value(struct pinmux_info *gpioc, unsigned gpio)
{
struct pinmux_data_reg *dr = NULL;
int bit = 0;
if (!gpioc || get_data_reg(gpioc, gpio, &dr, &bit) != 0) {
BUG();
return 0;
}
return gpio_read_reg(dr->reg, dr->reg_width, 1, bit);
}
static int sh_gpio_get(struct gpio_chip *chip, unsigned offset)
{
return sh_gpio_get_value(chip_to_pinmux(chip), offset);
}
static void sh_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
sh_gpio_set_value(chip_to_pinmux(chip), offset, value);
}
int register_pinmux(struct pinmux_info *pip)
{
struct gpio_chip *chip = &pip->chip;
pr_info("sh pinmux: %s handling gpio %d -> %d\n",
pip->name, pip->first_gpio, pip->last_gpio);
setup_data_regs(pip);
chip->request = sh_gpio_request;
chip->free = sh_gpio_free;
chip->direction_input = sh_gpio_direction_input;
chip->get = sh_gpio_get;
chip->direction_output = sh_gpio_direction_output;
chip->set = sh_gpio_set;
WARN_ON(pip->first_gpio != 0); /* needs testing */
chip->label = pip->name;
chip->owner = THIS_MODULE;
chip->base = pip->first_gpio;
chip->ngpio = (pip->last_gpio - pip->first_gpio) + 1;
return gpiochip_add(chip);
}