linux/drivers/pinctrl/pinconf-generic.c
Yingjoe Chen d9ac5e25f1 pinctrl: update document for pinconf_generic_parse_dt_config
The returned configs from pinconf_generic_parse_dt_config() is
duplicated from original. Make it clear it must be freed when no
longer necessary.

Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-12-01 11:11:05 +01:00

395 lines
11 KiB
C

/*
* 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"
#include "pinctrl-utils.h"
#ifdef CONFIG_DEBUG_FS
static const struct pin_config_item conf_items[] = {
PCONFDUMP(PIN_CONFIG_BIAS_BUS_HOLD, "input bias bus hold", NULL, false),
PCONFDUMP(PIN_CONFIG_BIAS_DISABLE, "input bias disabled", NULL, false),
PCONFDUMP(PIN_CONFIG_BIAS_HIGH_IMPEDANCE, "input bias high impedance", NULL, false),
PCONFDUMP(PIN_CONFIG_BIAS_PULL_DOWN, "input bias pull down", NULL, false),
PCONFDUMP(PIN_CONFIG_BIAS_PULL_PIN_DEFAULT,
"input bias pull to pin specific state", NULL, false),
PCONFDUMP(PIN_CONFIG_BIAS_PULL_UP, "input bias pull up", NULL, false),
PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_DRAIN, "output drive open drain", NULL, false),
PCONFDUMP(PIN_CONFIG_DRIVE_OPEN_SOURCE, "output drive open source", NULL, false),
PCONFDUMP(PIN_CONFIG_DRIVE_PUSH_PULL, "output drive push pull", NULL, false),
PCONFDUMP(PIN_CONFIG_DRIVE_STRENGTH, "output drive strength", "mA", true),
PCONFDUMP(PIN_CONFIG_INPUT_DEBOUNCE, "input debounce", "usec", true),
PCONFDUMP(PIN_CONFIG_INPUT_ENABLE, "input enabled", NULL, false),
PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT, "input schmitt trigger", NULL, false),
PCONFDUMP(PIN_CONFIG_INPUT_SCHMITT_ENABLE, "input schmitt enabled", NULL, false),
PCONFDUMP(PIN_CONFIG_LOW_POWER_MODE, "pin low power", "mode", true),
PCONFDUMP(PIN_CONFIG_OUTPUT, "pin output", "level", true),
PCONFDUMP(PIN_CONFIG_POWER_SOURCE, "pin power source", "selector", true),
PCONFDUMP(PIN_CONFIG_SLEW_RATE, "slew rate", NULL, true),
};
static void pinconf_generic_dump_one(struct pinctrl_dev *pctldev,
struct seq_file *s, const char *gname,
unsigned pin,
const struct pin_config_item *items,
int nitems)
{
int i;
for (i = 0; i < nitems; i++) {
unsigned long config;
int ret;
/* We want to check out this parameter */
config = pinconf_to_config_packed(items[i].param, 0);
if (gname)
ret = pin_config_group_get(dev_name(pctldev->dev),
gname, &config);
else
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, items[i].display);
/* Print unit if available */
if (items[i].has_arg) {
seq_printf(s, " (%u",
pinconf_to_config_argument(config));
if (items[i].format)
seq_printf(s, " %s)", items[i].format);
else
seq_puts(s, ")");
}
}
}
/**
* pinconf_generic_dump_pins - Print information about pin or group of pins
* @pctldev: Pincontrol device
* @s: File to print to
* @gname: Group name specifying pins
* @pin: Pin number specyfying pin
*
* Print the pinconf configuration for the requested pin(s) to @s. Pins can be
* specified either by pin using @pin or by group using @gname. Only one needs
* to be specified the other can be NULL/0.
*/
void pinconf_generic_dump_pins(struct pinctrl_dev *pctldev, struct seq_file *s,
const char *gname, unsigned pin)
{
const struct pinconf_ops *ops = pctldev->desc->confops;
if (!ops->is_generic)
return;
/* generic parameters */
pinconf_generic_dump_one(pctldev, s, gname, pin, conf_items,
ARRAY_SIZE(conf_items));
/* driver-specific parameters */
if (pctldev->desc->num_custom_params &&
pctldev->desc->custom_conf_items)
pinconf_generic_dump_one(pctldev, s, gname, pin,
pctldev->desc->custom_conf_items,
pctldev->desc->num_custom_params);
}
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));
}
if (!pctldev->desc->num_custom_params ||
!pctldev->desc->custom_conf_items)
return;
for (i = 0; i < pctldev->desc->num_custom_params; i++) {
if (pinconf_to_config_param(config) !=
pctldev->desc->custom_conf_items[i].param)
continue;
seq_printf(s, "%s: 0x%x",
pctldev->desc->custom_conf_items[i].display,
pinconf_to_config_argument(config));
}
}
EXPORT_SYMBOL_GPL(pinconf_generic_dump_config);
#endif
#ifdef CONFIG_OF
static const struct pinconf_generic_params dt_params[] = {
{ "bias-bus-hold", PIN_CONFIG_BIAS_BUS_HOLD, 0 },
{ "bias-disable", PIN_CONFIG_BIAS_DISABLE, 0 },
{ "bias-high-impedance", PIN_CONFIG_BIAS_HIGH_IMPEDANCE, 0 },
{ "bias-pull-up", PIN_CONFIG_BIAS_PULL_UP, 1 },
{ "bias-pull-pin-default", PIN_CONFIG_BIAS_PULL_PIN_DEFAULT, 1 },
{ "bias-pull-down", PIN_CONFIG_BIAS_PULL_DOWN, 1 },
{ "drive-open-drain", PIN_CONFIG_DRIVE_OPEN_DRAIN, 0 },
{ "drive-open-source", PIN_CONFIG_DRIVE_OPEN_SOURCE, 0 },
{ "drive-push-pull", PIN_CONFIG_DRIVE_PUSH_PULL, 0 },
{ "drive-strength", PIN_CONFIG_DRIVE_STRENGTH, 0 },
{ "input-debounce", PIN_CONFIG_INPUT_DEBOUNCE, 0 },
{ "input-disable", PIN_CONFIG_INPUT_ENABLE, 0 },
{ "input-enable", PIN_CONFIG_INPUT_ENABLE, 1 },
{ "input-schmitt", PIN_CONFIG_INPUT_SCHMITT, 0 },
{ "input-schmitt-disable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 0 },
{ "input-schmitt-enable", PIN_CONFIG_INPUT_SCHMITT_ENABLE, 1 },
{ "low-power-disable", PIN_CONFIG_LOW_POWER_MODE, 0 },
{ "low-power-enable", PIN_CONFIG_LOW_POWER_MODE, 1 },
{ "output-high", PIN_CONFIG_OUTPUT, 1, },
{ "output-low", PIN_CONFIG_OUTPUT, 0, },
{ "power-source", PIN_CONFIG_POWER_SOURCE, 0 },
{ "slew-rate", PIN_CONFIG_SLEW_RATE, 0 },
};
/**
* parse_dt_cfg() - Parse DT pinconf parameters
* @np: DT node
* @params: Array of describing generic parameters
* @count: Number of entries in @params
* @cfg: Array of parsed config options
* @ncfg: Number of entries in @cfg
*
* Parse the config options described in @params from @np and puts the result
* in @cfg. @cfg does not need to be empty, entries are added beggining at
* @ncfg. @ncfg is updated to reflect the number of entries after parsing. @cfg
* needs to have enough memory allocated to hold all possible entries.
*/
static void parse_dt_cfg(struct device_node *np,
const struct pinconf_generic_params *params,
unsigned int count, unsigned long *cfg,
unsigned int *ncfg)
{
int i;
for (i = 0; i < count; i++) {
u32 val;
int ret;
const struct pinconf_generic_params *par = &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)++;
}
}
/**
* 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
* must be freed when no longer necessary.
* @nconfigs: umber of configurations
*/
int pinconf_generic_parse_dt_config(struct device_node *np,
struct pinctrl_dev *pctldev,
unsigned long **configs,
unsigned int *nconfigs)
{
unsigned long *cfg;
unsigned int max_cfg, ncfg = 0;
int ret;
if (!np)
return -EINVAL;
/* allocate a temporary array big enough to hold one of each option */
max_cfg = ARRAY_SIZE(dt_params);
if (pctldev)
max_cfg += pctldev->desc->num_custom_params;
cfg = kcalloc(max_cfg, sizeof(*cfg), GFP_KERNEL);
if (!cfg)
return -ENOMEM;
parse_dt_cfg(np, dt_params, ARRAY_SIZE(dt_params), cfg, &ncfg);
if (pctldev && pctldev->desc->num_custom_params &&
pctldev->desc->custom_params)
parse_dt_cfg(np, pctldev->desc->custom_params,
pctldev->desc->num_custom_params, cfg, &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 = kmemdup(cfg, ncfg * sizeof(unsigned long), GFP_KERNEL);
if (!*configs) {
ret = -ENOMEM;
goto out;
}
*nconfigs = ncfg;
out:
kfree(cfg);
return ret;
}
int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
struct device_node *np, struct pinctrl_map **map,
unsigned *reserved_maps, unsigned *num_maps,
enum pinctrl_map_type type)
{
int ret;
const char *function;
struct device *dev = pctldev->dev;
unsigned long *configs = NULL;
unsigned num_configs = 0;
unsigned reserve, strings_count;
struct property *prop;
const char *group;
const char *subnode_target_type = "pins";
ret = of_property_count_strings(np, "pins");
if (ret < 0) {
ret = of_property_count_strings(np, "groups");
if (ret < 0)
/* skip this node; may contain config child nodes */
return 0;
if (type == PIN_MAP_TYPE_INVALID)
type = PIN_MAP_TYPE_CONFIGS_GROUP;
subnode_target_type = "groups";
} else {
if (type == PIN_MAP_TYPE_INVALID)
type = PIN_MAP_TYPE_CONFIGS_PIN;
}
strings_count = ret;
ret = of_property_read_string(np, "function", &function);
if (ret < 0) {
/* EINVAL=missing, which is fine since it's optional */
if (ret != -EINVAL)
dev_err(dev, "%s: could not parse property function\n",
of_node_full_name(np));
function = NULL;
}
ret = pinconf_generic_parse_dt_config(np, pctldev, &configs,
&num_configs);
if (ret < 0) {
dev_err(dev, "%s: could not parse node property\n",
of_node_full_name(np));
return ret;
}
reserve = 0;
if (function != NULL)
reserve++;
if (num_configs)
reserve++;
reserve *= strings_count;
ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps,
num_maps, reserve);
if (ret < 0)
goto exit;
of_property_for_each_string(np, subnode_target_type, prop, group) {
if (function) {
ret = pinctrl_utils_add_map_mux(pctldev, map,
reserved_maps, num_maps, group,
function);
if (ret < 0)
goto exit;
}
if (num_configs) {
ret = pinctrl_utils_add_map_configs(pctldev, map,
reserved_maps, num_maps, group, configs,
num_configs, type);
if (ret < 0)
goto exit;
}
}
ret = 0;
exit:
kfree(configs);
return ret;
}
EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map);
int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev,
struct device_node *np_config, struct pinctrl_map **map,
unsigned *num_maps, enum pinctrl_map_type type)
{
unsigned reserved_maps;
struct device_node *np;
int ret;
reserved_maps = 0;
*map = NULL;
*num_maps = 0;
ret = pinconf_generic_dt_subnode_to_map(pctldev, np_config, map,
&reserved_maps, num_maps, type);
if (ret < 0)
goto exit;
for_each_child_of_node(np_config, np) {
ret = pinconf_generic_dt_subnode_to_map(pctldev, np, map,
&reserved_maps, num_maps, type);
if (ret < 0)
goto exit;
}
return 0;
exit:
pinctrl_utils_dt_free_map(pctldev, *map, *num_maps);
return ret;
}
EXPORT_SYMBOL_GPL(pinconf_generic_dt_node_to_map);
#endif