linux/drivers/pinctrl/pinconf-generic.c

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/*
* Core driver for the generic 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) "generic 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/pinctrl.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/of.h>
#include "core.h"
#include "pinconf.h"
#ifdef CONFIG_DEBUG_FS
struct pin_config_item {
const enum pin_config_param param;
const char * const display;
const char * const format;
};
#define PCONFDUMP(a, b, c) { .param = a, .display = b, .format = c }
static struct pin_config_item conf_items[] = {
PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL),
PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL),
PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL),
PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL),
PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL),
PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
"input bias pull to pin specific state", NULL),
PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL),
PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL),
PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL),
PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH, "output drive strength", "mA"),
PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL),
PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL),
PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "usec"),
PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector"),
PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL),
PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode"),
PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level"),
};
void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev,
struct seq_file *s, unsigned pin)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
int i;
if (!ops->is_generic)
return;
for (i = 0; i < ARRAY_SIZE(conf_items); i++) {
unsigned long config;
int ret;
/* We want to check out this parameter */
config = pinconf_to_config_packed(conf_items[i].param, 0);
ret = pin_config_get_for_pin(pctldev, pin, &config);
/* These are legal errors */
if (ret == -EINVAL || ret == -ENOTSUPP)
continue;
if (ret) {
seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
continue;
}
/* Space between multiple configs */
seq_puts(s, " ");
seq_puts(s, conf_items[i].display);
/* Print unit if available */
if (conf_items[i].format &&
pinconf_to_config_argument(config) != 0)
seq_printf(s, " (%u %s)",
pinconf_to_config_argument(config),
conf_items[i].format);
}
}
void pinconf_generic_dump_group(struct pinctrl_dev *pctldev,
struct seq_file *s, const char *gname)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
int i;
if (!ops->is_generic)
return;
for (i = 0; i < ARRAY_SIZE(conf_items); i++) {
unsigned long config;
int ret;
/* We want to check out this parameter */
config = pinconf_to_config_packed(conf_items[i].param, 0);
ret = pin_config_group_get(dev_name(pctldev->dev), gname,
&config);
/* These are legal errors */
if (ret == -EINVAL || ret == -ENOTSUPP)
continue;
if (ret) {
seq_printf(s, "ERROR READING CONFIG SETTING %d ", i);
continue;
}
/* Space between multiple configs */
seq_puts(s, " ");
seq_puts(s, conf_items[i].display);
/* Print unit if available */
if (conf_items[i].format && config != 0)
seq_printf(s, " (%u %s)",
pinconf_to_config_argument(config),
conf_items[i].format);
}
}
void pinconf_generic_dump_config(struct pinctrl_dev *pctldev,
struct seq_file *s, unsigned long config)
{
int i;
for (i = 0; i < ARRAY_SIZE(conf_items); i++) {
if (pinconf_to_config_param(config) != conf_items[i].param)
continue;
seq_printf(s, "%s: 0x%x", conf_items[i].display,
pinconf_to_config_argument(config));
}
}
EXPORT_SYMBOL_GPL(pinconf_generic_dump_config);
#endif
#ifdef CONFIG_OF
struct pinconf_generic_dt_params {
const char * const property;
enum pin_config_param param;
u32 default_value;
};
static struct pinconf_generic_dt_params dt_params[] = {
{ "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
{ "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 },
{ "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 },
{ "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 },
{ "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 },
{ "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 },
{ "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 },
{ "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 },
{ "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 },
{ "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 },
{ "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 },
{ "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 },
{ "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 },
{ "low-power-enable", PIN_CONFIG_LOW_POWER_MODE, 1 },
{ "low-power-disable", PIN_CONFIG_LOW_POWER_MODE, 0 },
{ "output-low", PIN_CONFIG_OUTPUT, 0, },
{ "output-high", PIN_CONFIG_OUTPUT, 1, },
};
/**
* pinconf_generic_parse_dt_config()
* parse the config properties into generic pinconfig values.
* @np: node containing the pinconfig properties
* @configs: array with nconfigs entries containing the generic pinconf values
* @nconfigs: umber of configurations
*/
int pinconf_generic_parse_dt_config(struct device_node *np,
unsigned long **configs,
unsigned int *nconfigs)
{
unsigned long *cfg;
unsigned int ncfg = 0;
int ret;
int i;
u32 val;
if (!np)
return -EINVAL;
/* allocate a temporary array big enough to hold one of each option */
cfg = kzalloc(sizeof(*cfg) * ARRAY_SIZE(dt_params), GFP_KERNEL);
if (!cfg)
return -ENOMEM;
for (i = 0; i < ARRAY_SIZE(dt_params); i++) {
struct pinconf_generic_dt_params *par = &dt_params[i];
ret = of_property_read_u32(np, par->property, &val);
/* property not found */
if (ret == -EINVAL)
continue;
/* use default value, when no value is specified */
if (ret)
val = par->default_value;
pr_debug("found %s with value %u\n", par->property, val);
cfg[ncfg] = pinconf_to_config_packed(par->param, val);
ncfg++;
}
ret = 0;
/* no configs found at all */
if (ncfg == 0) {
*configs = NULL;
*nconfigs = 0;
goto out;
}
/*
* Now limit the number of configs to the real number of
* found properties.
*/
*configs = kzalloc(ncfg * sizeof(unsigned long), GFP_KERNEL);
if (!*configs) {
ret = -ENOMEM;
goto out;
}
memcpy(*configs, cfg, ncfg * sizeof(unsigned long));
*nconfigs = ncfg;
out:
kfree(cfg);
return ret;
}
#endif