android_kernel_xiaomi_sm8350/arch/sh/kernel/gpio.c
Magnus Damm 42eed42bac sh: improve pinmux support for single direction pins
This patch improves the support for gpio pins that are hard wired
to either input or output and lack control register association.
A special force enum id is used to allow use without control
register but still mark the gpio pin as input or output.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2008-10-22 18:34:16 +09:00

503 lines
9.8 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 struct pinmux_info *registered_gpio;
static struct pinmux_info *gpio_controller(unsigned gpio)
{
if (!registered_gpio)
return NULL;
if (gpio < registered_gpio->first_gpio)
return NULL;
if (gpio > registered_gpio->last_gpio)
return NULL;
return registered_gpio;
}
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 int read_write_reg(unsigned long reg, unsigned long reg_width,
unsigned long field_width, unsigned long in_pos,
unsigned long value, int do_write)
{
unsigned long data, mask, pos;
data = 0;
mask = (1 << field_width) - 1;
pos = reg_width - ((in_pos + 1) * field_width);
#ifdef DEBUG
pr_info("%s, addr = %lx, value = %ld, pos = %ld, "
"r_width = %ld, f_width = %ld\n",
do_write ? "write" : "read", reg, value, pos,
reg_width, field_width);
#endif
switch (reg_width) {
case 8:
data = ctrl_inb(reg);
break;
case 16:
data = ctrl_inw(reg);
break;
case 32:
data = ctrl_inl(reg);
break;
}
if (!do_write)
return (data >> pos) & mask;
data &= ~(mask << pos);
data |= value << pos;
switch (reg_width) {
case 8:
ctrl_outb(data, reg);
break;
case 16:
ctrl_outw(data, reg);
break;
case 32:
ctrl_outl(data, reg);
break;
}
return 0;
}
static int get_data_reg(struct pinmux_info *gpioc, unsigned gpio,
struct pinmux_data_reg **drp, int *bitp)
{
pinmux_enum_t enum_id = gpioc->gpios[gpio].enum_id;
struct pinmux_data_reg *data_reg;
int k, n;
if (!enum_in_range(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] == enum_id) {
*drp = data_reg;
*bitp = n;
return 0;
}
}
k++;
}
return -1;
}
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 int 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;
return read_write_reg(crp->reg, crp->reg_width,
crp->field_width, pos, value, 1);
}
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 (read_write_reg(crp->reg, crp->reg_width,
crp->field_width, pos, 0, 0) == value)
return 0;
return -1;
}
enum { GPIO_CFG_DRYRUN, GPIO_CFG_REQ, GPIO_CFG_FREE };
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:
if (write_config_reg(gpioc, cr, index) != 0)
goto out_err;
*cntp = *cntp + 1;
break;
case GPIO_CFG_FREE:
*cntp = *cntp - 1;
break;
}
}
return 0;
out_err:
return -1;
}
static DEFINE_SPINLOCK(gpio_lock);
int __gpio_request(unsigned gpio)
{
struct pinmux_info *gpioc = gpio_controller(gpio);
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[gpio].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, gpio, &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, gpio,
pinmux_type,
GPIO_CFG_DRYRUN) != 0)
goto err_unlock;
if (pinmux_config_gpio(gpioc, gpio,
pinmux_type,
GPIO_CFG_REQ) != 0)
BUG();
}
gpioc->gpios[gpio].flags = pinmux_type;
ret = 0;
err_unlock:
spin_unlock_irqrestore(&gpio_lock, flags);
err_out:
return ret;
}
EXPORT_SYMBOL(__gpio_request);
void gpio_free(unsigned gpio)
{
struct pinmux_info *gpioc = gpio_controller(gpio);
unsigned long flags;
int pinmux_type;
if (!gpioc)
return;
spin_lock_irqsave(&gpio_lock, flags);
pinmux_type = gpioc->gpios[gpio].flags & PINMUX_FLAG_TYPE;
pinmux_config_gpio(gpioc, gpio, pinmux_type, GPIO_CFG_FREE);
gpioc->gpios[gpio].flags = PINMUX_TYPE_NONE;
spin_unlock_irqrestore(&gpio_lock, flags);
}
EXPORT_SYMBOL(gpio_free);
static int pinmux_direction(struct pinmux_info *gpioc,
unsigned gpio, int new_pinmux_type)
{
int ret, pinmux_type;
ret = -EINVAL;
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 = new_pinmux_type;
ret = 0;
err_out:
return ret;
}
int gpio_direction_input(unsigned gpio)
{
struct pinmux_info *gpioc = gpio_controller(gpio);
unsigned long flags;
int ret = -EINVAL;
if (!gpioc)
goto err_out;
spin_lock_irqsave(&gpio_lock, flags);
ret = pinmux_direction(gpioc, gpio, PINMUX_TYPE_INPUT);
spin_unlock_irqrestore(&gpio_lock, flags);
err_out:
return ret;
}
EXPORT_SYMBOL(gpio_direction_input);
static int __gpio_get_set_value(struct pinmux_info *gpioc,
unsigned gpio, int value,
int do_write)
{
struct pinmux_data_reg *dr = NULL;
int bit = 0;
if (get_data_reg(gpioc, gpio, &dr, &bit) != 0)
BUG();
else
value = read_write_reg(dr->reg, dr->reg_width,
1, bit, !!value, do_write);
return value;
}
int gpio_direction_output(unsigned gpio, int value)
{
struct pinmux_info *gpioc = gpio_controller(gpio);
unsigned long flags;
int ret = -EINVAL;
if (!gpioc)
goto err_out;
spin_lock_irqsave(&gpio_lock, flags);
__gpio_get_set_value(gpioc, gpio, value, 1);
ret = pinmux_direction(gpioc, gpio, PINMUX_TYPE_OUTPUT);
spin_unlock_irqrestore(&gpio_lock, flags);
err_out:
return ret;
}
EXPORT_SYMBOL(gpio_direction_output);
int gpio_get_value(unsigned gpio)
{
struct pinmux_info *gpioc = gpio_controller(gpio);
unsigned long flags;
int value = 0;
if (!gpioc)
BUG();
else {
spin_lock_irqsave(&gpio_lock, flags);
value = __gpio_get_set_value(gpioc, gpio, 0, 0);
spin_unlock_irqrestore(&gpio_lock, flags);
}
return value;
}
EXPORT_SYMBOL(gpio_get_value);
void gpio_set_value(unsigned gpio, int value)
{
struct pinmux_info *gpioc = gpio_controller(gpio);
unsigned long flags;
if (!gpioc)
BUG();
else {
spin_lock_irqsave(&gpio_lock, flags);
__gpio_get_set_value(gpioc, gpio, value, 1);
spin_unlock_irqrestore(&gpio_lock, flags);
}
}
EXPORT_SYMBOL(gpio_set_value);
int register_pinmux(struct pinmux_info *pip)
{
registered_gpio = pip;
pr_info("pinmux: %s handling gpio %d -> %d\n",
pip->name, pip->first_gpio, pip->last_gpio);
return 0;
}