u-boot/drivers/gpio/gpio-uclass.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

864 lines
19 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2013 Google, Inc
*/
#include <common.h>
#include <dm.h>
#include <dt-bindings/gpio/gpio.h>
#include <errno.h>
#include <fdtdec.h>
#include <malloc.h>
#include <asm/gpio.h>
#include <linux/bug.h>
#include <linux/ctype.h>
DECLARE_GLOBAL_DATA_PTR;
/**
* gpio_to_device() - Convert global GPIO number to device, number
*
* Convert the GPIO number to an entry in the list of GPIOs
* or GPIO blocks registered with the GPIO controller. Returns
* entry on success, NULL on error.
*
* @gpio: The numeric representation of the GPIO
* @desc: Returns description (desc->flags will always be 0)
* @return 0 if found, -ENOENT if not found
*/
static int gpio_to_device(unsigned int gpio, struct gpio_desc *desc)
{
struct gpio_dev_priv *uc_priv;
struct udevice *dev;
int ret;
for (ret = uclass_first_device(UCLASS_GPIO, &dev);
dev;
ret = uclass_next_device(&dev)) {
uc_priv = dev_get_uclass_priv(dev);
if (gpio >= uc_priv->gpio_base &&
gpio < uc_priv->gpio_base + uc_priv->gpio_count) {
desc->dev = dev;
desc->offset = gpio - uc_priv->gpio_base;
desc->flags = 0;
return 0;
}
}
/* No such GPIO */
return ret ? ret : -ENOENT;
}
int dm_gpio_lookup_name(const char *name, struct gpio_desc *desc)
{
struct gpio_dev_priv *uc_priv = NULL;
struct udevice *dev;
ulong offset;
int numeric;
int ret;
numeric = isdigit(*name) ? simple_strtoul(name, NULL, 10) : -1;
for (ret = uclass_first_device(UCLASS_GPIO, &dev);
dev;
ret = uclass_next_device(&dev)) {
int len;
uc_priv = dev_get_uclass_priv(dev);
if (numeric != -1) {
offset = numeric - uc_priv->gpio_base;
/* Allow GPIOs to be numbered from 0 */
if (offset < uc_priv->gpio_count)
break;
}
len = uc_priv->bank_name ? strlen(uc_priv->bank_name) : 0;
if (!strncasecmp(name, uc_priv->bank_name, len)) {
if (!strict_strtoul(name + len, 10, &offset))
break;
}
}
if (!dev)
return ret ? ret : -EINVAL;
desc->dev = dev;
desc->offset = offset;
return 0;
}
int gpio_lookup_name(const char *name, struct udevice **devp,
unsigned int *offsetp, unsigned int *gpiop)
{
struct gpio_desc desc;
int ret;
if (devp)
*devp = NULL;
ret = dm_gpio_lookup_name(name, &desc);
if (ret)
return ret;
if (devp)
*devp = desc.dev;
if (offsetp)
*offsetp = desc.offset;
if (gpiop) {
struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(desc.dev);
*gpiop = uc_priv->gpio_base + desc.offset;
}
return 0;
}
int gpio_xlate_offs_flags(struct udevice *dev, struct gpio_desc *desc,
struct ofnode_phandle_args *args)
{
if (args->args_count < 1)
return -EINVAL;
desc->offset = args->args[0];
if (args->args_count < 2)
return 0;
if (args->args[1] & GPIO_ACTIVE_LOW)
desc->flags = GPIOD_ACTIVE_LOW;
return 0;
}
static int gpio_find_and_xlate(struct gpio_desc *desc,
struct ofnode_phandle_args *args)
{
struct dm_gpio_ops *ops = gpio_get_ops(desc->dev);
if (ops->xlate)
return ops->xlate(desc->dev, desc, args);
else
return gpio_xlate_offs_flags(desc->dev, desc, args);
}
int dm_gpio_request(struct gpio_desc *desc, const char *label)
{
struct udevice *dev = desc->dev;
struct gpio_dev_priv *uc_priv;
char *str;
int ret;
uc_priv = dev_get_uclass_priv(dev);
if (uc_priv->name[desc->offset])
return -EBUSY;
str = strdup(label);
if (!str)
return -ENOMEM;
if (gpio_get_ops(dev)->request) {
ret = gpio_get_ops(dev)->request(dev, desc->offset, label);
if (ret) {
free(str);
return ret;
}
}
uc_priv->name[desc->offset] = str;
return 0;
}
static int dm_gpio_requestf(struct gpio_desc *desc, const char *fmt, ...)
{
#if !defined(CONFIG_SPL_BUILD) || !defined(CONFIG_USE_TINY_PRINTF)
va_list args;
char buf[40];
va_start(args, fmt);
vscnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
return dm_gpio_request(desc, buf);
#else
return dm_gpio_request(desc, fmt);
#endif
}
/**
* gpio_request() - [COMPAT] Request GPIO
* gpio: GPIO number
* label: Name for the requested GPIO
*
* The label is copied and allocated so the caller does not need to keep
* the pointer around.
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns 0 on success, negative value on error.
*/
int gpio_request(unsigned gpio, const char *label)
{
struct gpio_desc desc;
int ret;
ret = gpio_to_device(gpio, &desc);
if (ret)
return ret;
return dm_gpio_request(&desc, label);
}
/**
* gpio_requestf() - [COMPAT] Request GPIO
* @gpio: GPIO number
* @fmt: Format string for the requested GPIO
* @...: Arguments for the printf() format string
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns 0 on success, negative value on error.
*/
int gpio_requestf(unsigned gpio, const char *fmt, ...)
{
#if !defined(CONFIG_SPL_BUILD) || !defined(CONFIG_USE_TINY_PRINTF)
va_list args;
char buf[40];
va_start(args, fmt);
vscnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
return gpio_request(gpio, buf);
#else
return gpio_request(gpio, fmt);
#endif
}
int _dm_gpio_free(struct udevice *dev, uint offset)
{
struct gpio_dev_priv *uc_priv;
int ret;
uc_priv = dev_get_uclass_priv(dev);
if (!uc_priv->name[offset])
return -ENXIO;
if (gpio_get_ops(dev)->free) {
ret = gpio_get_ops(dev)->free(dev, offset);
if (ret)
return ret;
}
free(uc_priv->name[offset]);
uc_priv->name[offset] = NULL;
return 0;
}
/**
* gpio_free() - [COMPAT] Relinquish GPIO
* gpio: GPIO number
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns 0 on success, negative value on error.
*/
int gpio_free(unsigned gpio)
{
struct gpio_desc desc;
int ret;
ret = gpio_to_device(gpio, &desc);
if (ret)
return ret;
return _dm_gpio_free(desc.dev, desc.offset);
}
static int check_reserved(const struct gpio_desc *desc, const char *func)
{
struct gpio_dev_priv *uc_priv;
if (!dm_gpio_is_valid(desc))
return -ENOENT;
uc_priv = dev_get_uclass_priv(desc->dev);
if (!uc_priv->name[desc->offset]) {
printf("%s: %s: error: gpio %s%d not reserved\n",
desc->dev->name, func,
uc_priv->bank_name ? uc_priv->bank_name : "",
desc->offset);
return -EBUSY;
}
return 0;
}
/**
* gpio_direction_input() - [COMPAT] Set GPIO direction to input
* gpio: GPIO number
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns 0 on success, negative value on error.
*/
int gpio_direction_input(unsigned gpio)
{
struct gpio_desc desc;
int ret;
ret = gpio_to_device(gpio, &desc);
if (ret)
return ret;
ret = check_reserved(&desc, "dir_input");
if (ret)
return ret;
return gpio_get_ops(desc.dev)->direction_input(desc.dev, desc.offset);
}
/**
* gpio_direction_output() - [COMPAT] Set GPIO direction to output and set value
* gpio: GPIO number
* value: Logical value to be set on the GPIO pin
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns 0 on success, negative value on error.
*/
int gpio_direction_output(unsigned gpio, int value)
{
struct gpio_desc desc;
int ret;
ret = gpio_to_device(gpio, &desc);
if (ret)
return ret;
ret = check_reserved(&desc, "dir_output");
if (ret)
return ret;
return gpio_get_ops(desc.dev)->direction_output(desc.dev,
desc.offset, value);
}
int dm_gpio_get_value(const struct gpio_desc *desc)
{
int value;
int ret;
ret = check_reserved(desc, "get_value");
if (ret)
return ret;
value = gpio_get_ops(desc->dev)->get_value(desc->dev, desc->offset);
return desc->flags & GPIOD_ACTIVE_LOW ? !value : value;
}
int dm_gpio_set_value(const struct gpio_desc *desc, int value)
{
int ret;
ret = check_reserved(desc, "set_value");
if (ret)
return ret;
if (desc->flags & GPIOD_ACTIVE_LOW)
value = !value;
gpio_get_ops(desc->dev)->set_value(desc->dev, desc->offset, value);
return 0;
}
int dm_gpio_get_open_drain(struct gpio_desc *desc)
{
struct dm_gpio_ops *ops = gpio_get_ops(desc->dev);
int ret;
ret = check_reserved(desc, "get_open_drain");
if (ret)
return ret;
if (ops->set_open_drain)
return ops->get_open_drain(desc->dev, desc->offset);
else
return -ENOSYS;
}
int dm_gpio_set_open_drain(struct gpio_desc *desc, int value)
{
struct dm_gpio_ops *ops = gpio_get_ops(desc->dev);
int ret;
ret = check_reserved(desc, "set_open_drain");
if (ret)
return ret;
if (ops->set_open_drain)
ret = ops->set_open_drain(desc->dev, desc->offset, value);
else
return 0; /* feature not supported -> ignore setting */
return ret;
}
int dm_gpio_set_dir_flags(struct gpio_desc *desc, ulong flags)
{
struct udevice *dev = desc->dev;
struct dm_gpio_ops *ops = gpio_get_ops(dev);
int ret;
ret = check_reserved(desc, "set_dir");
if (ret)
return ret;
if (flags & GPIOD_IS_OUT) {
int value = flags & GPIOD_IS_OUT_ACTIVE ? 1 : 0;
if (flags & GPIOD_ACTIVE_LOW)
value = !value;
ret = ops->direction_output(dev, desc->offset, value);
} else if (flags & GPIOD_IS_IN) {
ret = ops->direction_input(dev, desc->offset);
}
if (ret)
return ret;
/*
* Update desc->flags here, so that GPIO_ACTIVE_LOW is honoured in
* futures
*/
desc->flags = flags;
return 0;
}
int dm_gpio_set_dir(struct gpio_desc *desc)
{
return dm_gpio_set_dir_flags(desc, desc->flags);
}
/**
* gpio_get_value() - [COMPAT] Sample GPIO pin and return it's value
* gpio: GPIO number
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns the value of the GPIO pin, or negative value
* on error.
*/
int gpio_get_value(unsigned gpio)
{
int ret;
struct gpio_desc desc;
ret = gpio_to_device(gpio, &desc);
if (ret)
return ret;
return dm_gpio_get_value(&desc);
}
/**
* gpio_set_value() - [COMPAT] Configure logical value on GPIO pin
* gpio: GPIO number
* value: Logical value to be set on the GPIO pin.
*
* This function implements the API that's compatible with current
* GPIO API used in U-Boot. The request is forwarded to particular
* GPIO driver. Returns 0 on success, negative value on error.
*/
int gpio_set_value(unsigned gpio, int value)
{
struct gpio_desc desc;
int ret;
ret = gpio_to_device(gpio, &desc);
if (ret)
return ret;
return dm_gpio_set_value(&desc, value);
}
const char *gpio_get_bank_info(struct udevice *dev, int *bit_count)
{
struct gpio_dev_priv *priv;
/* Must be called on an active device */
priv = dev_get_uclass_priv(dev);
assert(priv);
*bit_count = priv->gpio_count;
return priv->bank_name;
}
static const char * const gpio_function[GPIOF_COUNT] = {
"input",
"output",
"unused",
"unknown",
"func",
};
static int get_function(struct udevice *dev, int offset, bool skip_unused,
const char **namep)
{
struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
struct dm_gpio_ops *ops = gpio_get_ops(dev);
BUILD_BUG_ON(GPIOF_COUNT != ARRAY_SIZE(gpio_function));
if (!device_active(dev))
return -ENODEV;
if (offset < 0 || offset >= uc_priv->gpio_count)
return -EINVAL;
if (namep)
*namep = uc_priv->name[offset];
if (skip_unused && !uc_priv->name[offset])
return GPIOF_UNUSED;
if (ops->get_function) {
int ret;
ret = ops->get_function(dev, offset);
if (ret < 0)
return ret;
if (ret >= ARRAY_SIZE(gpio_function))
return -ENODATA;
return ret;
}
return GPIOF_UNKNOWN;
}
int gpio_get_function(struct udevice *dev, int offset, const char **namep)
{
return get_function(dev, offset, true, namep);
}
int gpio_get_raw_function(struct udevice *dev, int offset, const char **namep)
{
return get_function(dev, offset, false, namep);
}
int gpio_get_status(struct udevice *dev, int offset, char *buf, int buffsize)
{
struct dm_gpio_ops *ops = gpio_get_ops(dev);
struct gpio_dev_priv *priv;
char *str = buf;
int func;
int ret;
int len;
BUILD_BUG_ON(GPIOF_COUNT != ARRAY_SIZE(gpio_function));
*buf = 0;
priv = dev_get_uclass_priv(dev);
ret = gpio_get_raw_function(dev, offset, NULL);
if (ret < 0)
return ret;
func = ret;
len = snprintf(str, buffsize, "%s%d: %s",
priv->bank_name ? priv->bank_name : "",
offset, gpio_function[func]);
if (func == GPIOF_INPUT || func == GPIOF_OUTPUT ||
func == GPIOF_UNUSED) {
const char *label;
bool used;
ret = ops->get_value(dev, offset);
if (ret < 0)
return ret;
used = gpio_get_function(dev, offset, &label) != GPIOF_UNUSED;
snprintf(str + len, buffsize - len, ": %d [%c]%s%s",
ret,
used ? 'x' : ' ',
used ? " " : "",
label ? label : "");
}
return 0;
}
int gpio_claim_vector(const int *gpio_num_array, const char *fmt)
{
int i, ret;
int gpio;
for (i = 0; i < 32; i++) {
gpio = gpio_num_array[i];
if (gpio == -1)
break;
ret = gpio_requestf(gpio, fmt, i);
if (ret)
goto err;
ret = gpio_direction_input(gpio);
if (ret) {
gpio_free(gpio);
goto err;
}
}
return 0;
err:
for (i--; i >= 0; i--)
gpio_free(gpio_num_array[i]);
return ret;
}
/*
* get a number comprised of multiple GPIO values. gpio_num_array points to
* the array of gpio pin numbers to scan, terminated by -1.
*/
int gpio_get_values_as_int(const int *gpio_list)
{
int gpio;
unsigned bitmask = 1;
unsigned vector = 0;
int ret;
while (bitmask &&
((gpio = *gpio_list++) != -1)) {
ret = gpio_get_value(gpio);
if (ret < 0)
return ret;
else if (ret)
vector |= bitmask;
bitmask <<= 1;
}
return vector;
}
int dm_gpio_get_values_as_int(const struct gpio_desc *desc_list, int count)
{
unsigned bitmask = 1;
unsigned vector = 0;
int ret, i;
for (i = 0; i < count; i++) {
ret = dm_gpio_get_value(&desc_list[i]);
if (ret < 0)
return ret;
else if (ret)
vector |= bitmask;
bitmask <<= 1;
}
return vector;
}
static int gpio_request_tail(int ret, ofnode node,
struct ofnode_phandle_args *args,
const char *list_name, int index,
struct gpio_desc *desc, int flags, bool add_index)
{
desc->dev = NULL;
desc->offset = 0;
desc->flags = 0;
if (ret)
goto err;
ret = uclass_get_device_by_ofnode(UCLASS_GPIO, args->node,
&desc->dev);
if (ret) {
debug("%s: uclass_get_device_by_ofnode failed\n", __func__);
goto err;
}
ret = gpio_find_and_xlate(desc, args);
if (ret) {
debug("%s: gpio_find_and_xlate failed\n", __func__);
goto err;
}
ret = dm_gpio_requestf(desc, add_index ? "%s.%s%d" : "%s.%s",
ofnode_get_name(node),
list_name, index);
if (ret) {
debug("%s: dm_gpio_requestf failed\n", __func__);
goto err;
}
ret = dm_gpio_set_dir_flags(desc, flags | desc->flags);
if (ret) {
debug("%s: dm_gpio_set_dir failed\n", __func__);
goto err;
}
return 0;
err:
debug("%s: Node '%s', property '%s', failed to request GPIO index %d: %d\n",
__func__, ofnode_get_name(node), list_name, index, ret);
return ret;
}
static int _gpio_request_by_name_nodev(ofnode node, const char *list_name,
int index, struct gpio_desc *desc,
int flags, bool add_index)
{
struct ofnode_phandle_args args;
int ret;
ret = ofnode_parse_phandle_with_args(node, list_name, "#gpio-cells", 0,
index, &args);
return gpio_request_tail(ret, node, &args, list_name, index, desc,
flags, add_index);
}
int gpio_request_by_name_nodev(ofnode node, const char *list_name, int index,
struct gpio_desc *desc, int flags)
{
return _gpio_request_by_name_nodev(node, list_name, index, desc, flags,
index > 0);
}
int gpio_request_by_name(struct udevice *dev, const char *list_name, int index,
struct gpio_desc *desc, int flags)
{
struct ofnode_phandle_args args;
int ret;
ret = dev_read_phandle_with_args(dev, list_name, "#gpio-cells", 0,
index, &args);
return gpio_request_tail(ret, dev_ofnode(dev), &args, list_name,
index, desc, flags, index > 0);
}
int gpio_request_list_by_name_nodev(ofnode node, const char *list_name,
struct gpio_desc *desc, int max_count,
int flags)
{
int count;
int ret;
for (count = 0; count < max_count; count++) {
ret = _gpio_request_by_name_nodev(node, list_name, count,
&desc[count], flags, true);
if (ret == -ENOENT)
break;
else if (ret)
goto err;
}
/* We ran out of GPIOs in the list */
return count;
err:
gpio_free_list_nodev(desc, count - 1);
return ret;
}
int gpio_request_list_by_name(struct udevice *dev, const char *list_name,
struct gpio_desc *desc, int max_count,
int flags)
{
/*
* This isn't ideal since we don't use dev->name in the debug()
* calls in gpio_request_by_name(), but we can do this until
* gpio_request_list_by_name_nodev() can be dropped.
*/
return gpio_request_list_by_name_nodev(dev_ofnode(dev), list_name, desc,
max_count, flags);
}
int gpio_get_list_count(struct udevice *dev, const char *list_name)
{
int ret;
ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev_of_offset(dev),
list_name, "#gpio-cells", 0, -1,
NULL);
if (ret) {
debug("%s: Node '%s', property '%s', GPIO count failed: %d\n",
__func__, dev->name, list_name, ret);
}
return ret;
}
int dm_gpio_free(struct udevice *dev, struct gpio_desc *desc)
{
/* For now, we don't do any checking of dev */
return _dm_gpio_free(desc->dev, desc->offset);
}
int gpio_free_list(struct udevice *dev, struct gpio_desc *desc, int count)
{
int i;
/* For now, we don't do any checking of dev */
for (i = 0; i < count; i++)
dm_gpio_free(dev, &desc[i]);
return 0;
}
int gpio_free_list_nodev(struct gpio_desc *desc, int count)
{
return gpio_free_list(NULL, desc, count);
}
/* We need to renumber the GPIOs when any driver is probed/removed */
static int gpio_renumber(struct udevice *removed_dev)
{
struct gpio_dev_priv *uc_priv;
struct udevice *dev;
struct uclass *uc;
unsigned base;
int ret;
ret = uclass_get(UCLASS_GPIO, &uc);
if (ret)
return ret;
/* Ensure that we have a base for each bank */
base = 0;
uclass_foreach_dev(dev, uc) {
if (device_active(dev) && dev != removed_dev) {
uc_priv = dev_get_uclass_priv(dev);
uc_priv->gpio_base = base;
base += uc_priv->gpio_count;
}
}
return 0;
}
int gpio_get_number(const struct gpio_desc *desc)
{
struct udevice *dev = desc->dev;
struct gpio_dev_priv *uc_priv;
if (!dev)
return -1;
uc_priv = dev->uclass_priv;
return uc_priv->gpio_base + desc->offset;
}
static int gpio_post_probe(struct udevice *dev)
{
struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
uc_priv->name = calloc(uc_priv->gpio_count, sizeof(char *));
if (!uc_priv->name)
return -ENOMEM;
return gpio_renumber(NULL);
}
static int gpio_pre_remove(struct udevice *dev)
{
struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
int i;
for (i = 0; i < uc_priv->gpio_count; i++) {
if (uc_priv->name[i])
free(uc_priv->name[i]);
}
free(uc_priv->name);
return gpio_renumber(dev);
}
UCLASS_DRIVER(gpio) = {
.id = UCLASS_GPIO,
.name = "gpio",
.flags = DM_UC_FLAG_SEQ_ALIAS,
.post_probe = gpio_post_probe,
.pre_remove = gpio_pre_remove,
.per_device_auto_alloc_size = sizeof(struct gpio_dev_priv),
};