linux/drivers/pinctrl/pinconf.c
Linus Walleij 394349f778 pinctrl: introduce generic pin config
This is a split-off from the earlier patch set which adds generic
pin configuration for the pin controllers that want it. Since
we may have a system with mixed generic and custom pin controllers,
we pass a boolean in the pin controller ops vtable to indicate
if it is generic.

ChangeLog v1->v5:
- Follow parent patch versioning number system.
- Document the semantic meaning of return values from pin config
  get functions, so we can iterate over pins and check their
  properties from debugfs as part of the generic config code.
- Use proper cast functions in the generic debugfs pin config
  file.
- Expand generic config to optionally cover groups too.
ChangeLog v5->v6:
- Update to match underlying changes.
ChangeLog v6->v7:
- Drop DRIVE_OFF parameter, use bias high impedance for this
- Delete argument for drive modes push-pull, od and os. These
  are now just state transitions.
- Delete slew rate rising/falling due to discussions on on
  proper semantics
- Drop config wakeup, struct irq_chip does this for now, add
  back if need be.
- Set PIN_CONFIG_END to 0x7fff making room for custom config
  parameters from 0x8000 and up.
- Prefix accessor functions with pinconf_
2012-03-12 22:49:02 +01:00

557 lines
13 KiB
C

/*
* Core driver for the pin config portions of the pin control subsystem
*
* Copyright (C) 2011 ST-Ericsson SA
* Written on behalf of Linaro for ST-Ericsson
*
* Author: Linus Walleij <linus.walleij@linaro.org>
*
* License terms: GNU General Public License (GPL) version 2
*/
#define pr_fmt(fmt) "pinconfig core: " fmt
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/device.h>
#include <linux/slab.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf.h>
#include "core.h"
#include "pinconf.h"
int pinconf_check_ops(struct pinctrl_dev *pctldev)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
/* We must be able to read out pin status */
if (!ops->pin_config_get && !ops->pin_config_group_get)
return -EINVAL;
/* We have to be able to config the pins in SOME way */
if (!ops->pin_config_set && !ops->pin_config_group_set)
return -EINVAL;
return 0;
}
int pinconf_validate_map(struct pinctrl_map const *map, int i)
{
if (!map->data.configs.group_or_pin) {
pr_err("failed to register map %s (%d): no group/pin given\n",
map->name, i);
return -EINVAL;
}
if (map->data.configs.num_configs &&
!map->data.configs.configs) {
pr_err("failed to register map %s (%d): no configs ptr given\n",
map->name, i);
return -EINVAL;
}
return 0;
}
int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
unsigned long *config)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
if (!ops || !ops->pin_config_get) {
dev_err(pctldev->dev, "cannot get pin configuration, missing "
"pin_config_get() function in driver\n");
return -EINVAL;
}
return ops->pin_config_get(pctldev, pin, config);
}
/**
* pin_config_get() - get the configuration of a single pin parameter
* @dev_name: name of the pin controller device for this pin
* @name: name of the pin to get the config for
* @config: the config pointed to by this argument will be filled in with the
* current pin state, it can be used directly by drivers as a numeral, or
* it can be dereferenced to any struct.
*/
int pin_config_get(const char *dev_name, const char *name,
unsigned long *config)
{
struct pinctrl_dev *pctldev;
int pin;
mutex_lock(&pinctrl_mutex);
pctldev = get_pinctrl_dev_from_devname(dev_name);
if (!pctldev) {
pin = -EINVAL;
goto unlock;
}
pin = pin_get_from_name(pctldev, name);
if (pin < 0)
goto unlock;
pin = pin_config_get_for_pin(pctldev, pin, config);
unlock:
mutex_unlock(&pinctrl_mutex);
return pin;
}
EXPORT_SYMBOL(pin_config_get);
static int pin_config_set_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
unsigned long config)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
int ret;
if (!ops || !ops->pin_config_set) {
dev_err(pctldev->dev, "cannot configure pin, missing "
"config function in driver\n");
return -EINVAL;
}
ret = ops->pin_config_set(pctldev, pin, config);
if (ret) {
dev_err(pctldev->dev,
"unable to set pin configuration on pin %d\n", pin);
return ret;
}
return 0;
}
/**
* pin_config_set() - set the configuration of a single pin parameter
* @dev_name: name of pin controller device for this pin
* @name: name of the pin to set the config for
* @config: the config in this argument will contain the desired pin state, it
* can be used directly by drivers as a numeral, or it can be dereferenced
* to any struct.
*/
int pin_config_set(const char *dev_name, const char *name,
unsigned long config)
{
struct pinctrl_dev *pctldev;
int pin, ret;
mutex_lock(&pinctrl_mutex);
pctldev = get_pinctrl_dev_from_devname(dev_name);
if (!pctldev) {
ret = -EINVAL;
goto unlock;
}
pin = pin_get_from_name(pctldev, name);
if (pin < 0) {
ret = pin;
goto unlock;
}
ret = pin_config_set_for_pin(pctldev, pin, config);
unlock:
mutex_unlock(&pinctrl_mutex);
return ret;
}
EXPORT_SYMBOL(pin_config_set);
int pin_config_group_get(const char *dev_name, const char *pin_group,
unsigned long *config)
{
struct pinctrl_dev *pctldev;
const struct pinconf_ops *ops;
int selector, ret;
mutex_lock(&pinctrl_mutex);
pctldev = get_pinctrl_dev_from_devname(dev_name);
if (!pctldev) {
ret = -EINVAL;
goto unlock;
}
ops = pctldev->desc->confops;
if (!ops || !ops->pin_config_group_get) {
dev_err(pctldev->dev, "cannot get configuration for pin "
"group, missing group config get function in "
"driver\n");
ret = -EINVAL;
goto unlock;
}
selector = pinctrl_get_group_selector(pctldev, pin_group);
if (selector < 0) {
ret = selector;
goto unlock;
}
ret = ops->pin_config_group_get(pctldev, selector, config);
unlock:
mutex_unlock(&pinctrl_mutex);
return ret;
}
EXPORT_SYMBOL(pin_config_group_get);
int pin_config_group_set(const char *dev_name, const char *pin_group,
unsigned long config)
{
struct pinctrl_dev *pctldev;
const struct pinconf_ops *ops;
const struct pinctrl_ops *pctlops;
int selector;
const unsigned *pins;
unsigned num_pins;
int ret;
int i;
mutex_lock(&pinctrl_mutex);
pctldev = get_pinctrl_dev_from_devname(dev_name);
if (!pctldev) {
ret = -EINVAL;
goto unlock;
}
ops = pctldev->desc->confops;
pctlops = pctldev->desc->pctlops;
if (!ops || (!ops->pin_config_group_set && !ops->pin_config_set)) {
dev_err(pctldev->dev, "cannot configure pin group, missing "
"config function in driver\n");
ret = -EINVAL;
goto unlock;
}
selector = pinctrl_get_group_selector(pctldev, pin_group);
if (selector < 0) {
ret = selector;
goto unlock;
}
ret = pctlops->get_group_pins(pctldev, selector, &pins, &num_pins);
if (ret) {
dev_err(pctldev->dev, "cannot configure pin group, error "
"getting pins\n");
goto unlock;
}
/*
* If the pin controller supports handling entire groups we use that
* capability.
*/
if (ops->pin_config_group_set) {
ret = ops->pin_config_group_set(pctldev, selector, config);
/*
* If the pin controller prefer that a certain group be handled
* pin-by-pin as well, it returns -EAGAIN.
*/
if (ret != -EAGAIN)
goto unlock;
}
/*
* If the controller cannot handle entire groups, we configure each pin
* individually.
*/
if (!ops->pin_config_set) {
ret = 0;
goto unlock;
}
for (i = 0; i < num_pins; i++) {
ret = ops->pin_config_set(pctldev, pins[i], config);
if (ret < 0)
goto unlock;
}
ret = 0;
unlock:
mutex_unlock(&pinctrl_mutex);
return ret;
}
EXPORT_SYMBOL(pin_config_group_set);
int pinconf_map_to_setting(struct pinctrl_map const *map,
struct pinctrl_setting *setting)
{
struct pinctrl_dev *pctldev = setting->pctldev;
int pin;
switch (setting->type) {
case PIN_MAP_TYPE_CONFIGS_PIN:
pin = pin_get_from_name(pctldev,
map->data.configs.group_or_pin);
if (pin < 0) {
dev_err(pctldev->dev, "could not map pin config for \"%s\"",
map->data.configs.group_or_pin);
return pin;
}
setting->data.configs.group_or_pin = pin;
break;
case PIN_MAP_TYPE_CONFIGS_GROUP:
pin = pinctrl_get_group_selector(pctldev,
map->data.configs.group_or_pin);
if (pin < 0) {
dev_err(pctldev->dev, "could not map group config for \"%s\"",
map->data.configs.group_or_pin);
return pin;
}
setting->data.configs.group_or_pin = pin;
break;
default:
return -EINVAL;
}
setting->data.configs.num_configs = map->data.configs.num_configs;
setting->data.configs.configs = map->data.configs.configs;
return 0;
}
void pinconf_free_setting(struct pinctrl_setting const *setting)
{
}
int pinconf_apply_setting(struct pinctrl_setting const *setting)
{
struct pinctrl_dev *pctldev = setting->pctldev;
const struct pinconf_ops *ops = pctldev->desc->confops;
int i, ret;
if (!ops) {
dev_err(pctldev->dev, "missing confops\n");
return -EINVAL;
}
switch (setting->type) {
case PIN_MAP_TYPE_CONFIGS_PIN:
if (!ops->pin_config_set) {
dev_err(pctldev->dev, "missing pin_config_set op\n");
return -EINVAL;
}
for (i = 0; i < setting->data.configs.num_configs; i++) {
ret = ops->pin_config_set(pctldev,
setting->data.configs.group_or_pin,
setting->data.configs.configs[i]);
if (ret < 0) {
dev_err(pctldev->dev,
"pin_config_set op failed for pin %d config %08lx\n",
setting->data.configs.group_or_pin,
setting->data.configs.configs[i]);
return ret;
}
}
break;
case PIN_MAP_TYPE_CONFIGS_GROUP:
if (!ops->pin_config_group_set) {
dev_err(pctldev->dev,
"missing pin_config_group_set op\n");
return -EINVAL;
}
for (i = 0; i < setting->data.configs.num_configs; i++) {
ret = ops->pin_config_group_set(pctldev,
setting->data.configs.group_or_pin,
setting->data.configs.configs[i]);
if (ret < 0) {
dev_err(pctldev->dev,
"pin_config_group_set op failed for group %d config %08lx\n",
setting->data.configs.group_or_pin,
setting->data.configs.configs[i]);
return ret;
}
}
break;
default:
return -EINVAL;
}
return 0;
}
#ifdef CONFIG_DEBUG_FS
void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map)
{
int i;
switch (map->type) {
case PIN_MAP_TYPE_CONFIGS_PIN:
seq_printf(s, "pin ");
break;
case PIN_MAP_TYPE_CONFIGS_GROUP:
seq_printf(s, "group ");
break;
default:
break;
}
seq_printf(s, "%s\n", map->data.configs.group_or_pin);
for (i = 0; i < map->data.configs.num_configs; i++)
seq_printf(s, "config %08lx\n", map->data.configs.configs[i]);
}
void pinconf_show_setting(struct seq_file *s,
struct pinctrl_setting const *setting)
{
struct pinctrl_dev *pctldev = setting->pctldev;
const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
struct pin_desc *desc;
int i;
switch (setting->type) {
case PIN_MAP_TYPE_CONFIGS_PIN:
desc = pin_desc_get(setting->pctldev,
setting->data.configs.group_or_pin);
seq_printf(s, "pin %s (%d)",
desc->name ? desc->name : "unnamed",
setting->data.configs.group_or_pin);
break;
case PIN_MAP_TYPE_CONFIGS_GROUP:
seq_printf(s, "group %s (%d)",
pctlops->get_group_name(pctldev,
setting->data.configs.group_or_pin),
setting->data.configs.group_or_pin);
break;
default:
break;
}
/*
* FIXME: We should really get the pin controler to dump the config
* values, so they can be decoded to something meaningful.
*/
for (i = 0; i < setting->data.configs.num_configs; i++)
seq_printf(s, " %08lx", setting->data.configs.configs[i]);
seq_printf(s, "\n");
}
static void pinconf_dump_pin(struct pinctrl_dev *pctldev,
struct seq_file *s, int pin)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
/* no-op when not using generic pin config */
pinconf_generic_dump_pin(pctldev, s, pin);
if (ops && ops->pin_config_dbg_show)
ops->pin_config_dbg_show(pctldev, s, pin);
}
static int pinconf_pins_show(struct seq_file *s, void *what)
{
struct pinctrl_dev *pctldev = s->private;
unsigned i, pin;
seq_puts(s, "Pin config settings per pin\n");
seq_puts(s, "Format: pin (name): pinmux setting array\n");
mutex_lock(&pinctrl_mutex);
/* The pin number can be retrived from the pin controller descriptor */
for (i = 0; i < pctldev->desc->npins; i++) {
struct pin_desc *desc;
pin = pctldev->desc->pins[i].number;
desc = pin_desc_get(pctldev, pin);
/* Skip if we cannot search the pin */
if (desc == NULL)
continue;
seq_printf(s, "pin %d (%s):", pin,
desc->name ? desc->name : "unnamed");
pinconf_dump_pin(pctldev, s, pin);
seq_printf(s, "\n");
}
mutex_unlock(&pinctrl_mutex);
return 0;
}
static void pinconf_dump_group(struct pinctrl_dev *pctldev,
struct seq_file *s, unsigned selector,
const char *gname)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
/* no-op when not using generic pin config */
pinconf_generic_dump_group(pctldev, s, gname);
if (ops && ops->pin_config_group_dbg_show)
ops->pin_config_group_dbg_show(pctldev, s, selector);
}
static int pinconf_groups_show(struct seq_file *s, void *what)
{
struct pinctrl_dev *pctldev = s->private;
const struct pinctrl_ops *pctlops = pctldev->desc->pctlops;
const struct pinconf_ops *ops = pctldev->desc->confops;
unsigned selector = 0;
if (!ops || !ops->pin_config_group_get)
return 0;
seq_puts(s, "Pin config settings per pin group\n");
seq_puts(s, "Format: group (name): pinmux setting array\n");
mutex_lock(&pinctrl_mutex);
while (pctlops->list_groups(pctldev, selector) >= 0) {
const char *gname = pctlops->get_group_name(pctldev, selector);
seq_printf(s, "%u (%s):", selector, gname);
pinconf_dump_group(pctldev, s, selector, gname);
seq_printf(s, "\n");
selector++;
}
mutex_unlock(&pinctrl_mutex);
return 0;
}
static int pinconf_pins_open(struct inode *inode, struct file *file)
{
return single_open(file, pinconf_pins_show, inode->i_private);
}
static int pinconf_groups_open(struct inode *inode, struct file *file)
{
return single_open(file, pinconf_groups_show, inode->i_private);
}
static const struct file_operations pinconf_pins_ops = {
.open = pinconf_pins_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static const struct file_operations pinconf_groups_ops = {
.open = pinconf_groups_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
void pinconf_init_device_debugfs(struct dentry *devroot,
struct pinctrl_dev *pctldev)
{
debugfs_create_file("pinconf-pins", S_IFREG | S_IRUGO,
devroot, pctldev, &pinconf_pins_ops);
debugfs_create_file("pinconf-groups", S_IFREG | S_IRUGO,
devroot, pctldev, &pinconf_groups_ops);
}
#endif