linux/drivers/pinctrl/berlin/berlin.c

349 lines
8.3 KiB
C

/*
* Marvell Berlin SoC pinctrl core driver
*
* Copyright (C) 2014 Marvell Technology Group Ltd.
*
* Antoine Ténart <antoine.tenart@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*/
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/slab.h>
#include "../core.h"
#include "../pinctrl-utils.h"
#include "berlin.h"
struct berlin_pinctrl {
struct regmap *regmap;
struct device *dev;
const struct berlin_pinctrl_desc *desc;
struct berlin_pinctrl_function *functions;
unsigned nfunctions;
struct pinctrl_dev *pctrl_dev;
};
static int berlin_pinctrl_get_group_count(struct pinctrl_dev *pctrl_dev)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
return pctrl->desc->ngroups;
}
static const char *berlin_pinctrl_get_group_name(struct pinctrl_dev *pctrl_dev,
unsigned group)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
return pctrl->desc->groups[group].name;
}
static int berlin_pinctrl_dt_node_to_map(struct pinctrl_dev *pctrl_dev,
struct device_node *node,
struct pinctrl_map **map,
unsigned *num_maps)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
struct property *prop;
const char *function_name, *group_name;
unsigned reserved_maps = 0;
int ret, ngroups;
*map = NULL;
*num_maps = 0;
ret = of_property_read_string(node, "function", &function_name);
if (ret) {
dev_err(pctrl->dev,
"missing function property in node %s\n",
node->name);
return -EINVAL;
}
ngroups = of_property_count_strings(node, "groups");
if (ngroups < 0) {
dev_err(pctrl->dev,
"missing groups property in node %s\n",
node->name);
return -EINVAL;
}
ret = pinctrl_utils_reserve_map(pctrl_dev, map, &reserved_maps,
num_maps, ngroups);
if (ret) {
dev_err(pctrl->dev, "can't reserve map: %d\n", ret);
return ret;
}
of_property_for_each_string(node, "groups", prop, group_name) {
ret = pinctrl_utils_add_map_mux(pctrl_dev, map, &reserved_maps,
num_maps, group_name,
function_name);
if (ret) {
dev_err(pctrl->dev, "can't add map: %d\n", ret);
return ret;
}
}
return 0;
}
static void berlin_pinctrl_dt_free_map(struct pinctrl_dev *pctrl_dev,
struct pinctrl_map *map,
unsigned nmaps)
{
int i;
for (i = 0; i < nmaps; i++) {
if (map[i].type == PIN_MAP_TYPE_MUX_GROUP) {
kfree(map[i].data.mux.group);
/* a function can be applied to multiple groups */
if (i == 0)
kfree(map[i].data.mux.function);
}
}
kfree(map);
}
static const struct pinctrl_ops berlin_pinctrl_ops = {
.get_groups_count = &berlin_pinctrl_get_group_count,
.get_group_name = &berlin_pinctrl_get_group_name,
.dt_node_to_map = &berlin_pinctrl_dt_node_to_map,
.dt_free_map = &berlin_pinctrl_dt_free_map,
};
static int berlin_pinmux_get_functions_count(struct pinctrl_dev *pctrl_dev)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
return pctrl->nfunctions;
}
static const char *berlin_pinmux_get_function_name(struct pinctrl_dev *pctrl_dev,
unsigned function)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
return pctrl->functions[function].name;
}
static int berlin_pinmux_get_function_groups(struct pinctrl_dev *pctrl_dev,
unsigned function,
const char * const **groups,
unsigned * const num_groups)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
*groups = pctrl->functions[function].groups;
*num_groups = pctrl->functions[function].ngroups;
return 0;
}
static struct berlin_desc_function *
berlin_pinctrl_find_function_by_name(struct berlin_pinctrl *pctrl,
const struct berlin_desc_group *group,
const char *fname)
{
struct berlin_desc_function *function = group->functions;
while (function->name) {
if (!strcmp(function->name, fname))
return function;
function++;
}
return NULL;
}
static int berlin_pinmux_enable(struct pinctrl_dev *pctrl_dev,
unsigned function,
unsigned group)
{
struct berlin_pinctrl *pctrl = pinctrl_dev_get_drvdata(pctrl_dev);
const struct berlin_desc_group *group_desc = pctrl->desc->groups + group;
struct berlin_pinctrl_function *func = pctrl->functions + function;
struct berlin_desc_function *function_desc =
berlin_pinctrl_find_function_by_name(pctrl, group_desc,
func->name);
u32 mask, val;
if (!function_desc)
return -EINVAL;
mask = GENMASK(group_desc->lsb + group_desc->bit_width - 1,
group_desc->lsb);
val = function_desc->muxval << group_desc->lsb;
regmap_update_bits(pctrl->regmap, group_desc->offset, mask, val);
return 0;
}
static const struct pinmux_ops berlin_pinmux_ops = {
.get_functions_count = &berlin_pinmux_get_functions_count,
.get_function_name = &berlin_pinmux_get_function_name,
.get_function_groups = &berlin_pinmux_get_function_groups,
.enable = &berlin_pinmux_enable,
};
static int berlin_pinctrl_add_function(struct berlin_pinctrl *pctrl,
const char *name)
{
struct berlin_pinctrl_function *function = pctrl->functions;
while (function->name) {
if (!strcmp(function->name, name)) {
function->ngroups++;
return -EEXIST;
}
function++;
}
function->name = name;
function->ngroups = 1;
pctrl->nfunctions++;
return 0;
}
static int berlin_pinctrl_build_state(struct platform_device *pdev)
{
struct berlin_pinctrl *pctrl = platform_get_drvdata(pdev);
struct berlin_desc_group const *desc_group;
struct berlin_desc_function const *desc_function;
int i, max_functions = 0;
pctrl->nfunctions = 0;
for (i = 0; i < pctrl->desc->ngroups; i++) {
desc_group = pctrl->desc->groups + i;
/* compute the maxiumum number of functions a group can have */
max_functions += 1 << (desc_group->bit_width + 1);
}
/* we will reallocate later */
pctrl->functions = devm_kzalloc(&pdev->dev,
max_functions * sizeof(*pctrl->functions),
GFP_KERNEL);
if (!pctrl->functions)
return -ENOMEM;
/* register all functions */
for (i = 0; i < pctrl->desc->ngroups; i++) {
desc_group = pctrl->desc->groups + i;
desc_function = desc_group->functions;
while (desc_function->name) {
berlin_pinctrl_add_function(pctrl, desc_function->name);
desc_function++;
}
}
pctrl->functions = krealloc(pctrl->functions,
pctrl->nfunctions * sizeof(*pctrl->functions),
GFP_KERNEL);
/* map functions to theirs groups */
for (i = 0; i < pctrl->desc->ngroups; i++) {
desc_group = pctrl->desc->groups + i;
desc_function = desc_group->functions;
while (desc_function->name) {
struct berlin_pinctrl_function
*function = pctrl->functions;
const char **groups;
bool found = false;
while (function->name) {
if (!strcmp(desc_function->name, function->name)) {
found = true;
break;
}
function++;
}
if (!found)
return -EINVAL;
if (!function->groups) {
function->groups =
devm_kzalloc(&pdev->dev,
function->ngroups * sizeof(char *),
GFP_KERNEL);
if (!function->groups)
return -ENOMEM;
}
groups = function->groups;
while (*groups)
groups++;
*groups = desc_group->name;
desc_function++;
}
}
return 0;
}
static struct pinctrl_desc berlin_pctrl_desc = {
.name = "berlin-pinctrl",
.pctlops = &berlin_pinctrl_ops,
.pmxops = &berlin_pinmux_ops,
.owner = THIS_MODULE,
};
int berlin_pinctrl_probe(struct platform_device *pdev,
const struct berlin_pinctrl_desc *desc)
{
struct device *dev = &pdev->dev;
struct berlin_pinctrl *pctrl;
struct regmap *regmap;
int ret;
regmap = dev_get_regmap(&pdev->dev, NULL);
if (!regmap)
return PTR_ERR(regmap);
pctrl = devm_kzalloc(dev, sizeof(*pctrl), GFP_KERNEL);
if (!pctrl)
return -ENOMEM;
platform_set_drvdata(pdev, pctrl);
pctrl->regmap = regmap;
pctrl->dev = &pdev->dev;
pctrl->desc = desc;
ret = berlin_pinctrl_build_state(pdev);
if (ret) {
dev_err(dev, "cannot build driver state: %d\n", ret);
return ret;
}
pctrl->pctrl_dev = pinctrl_register(&berlin_pctrl_desc, dev, pctrl);
if (!pctrl->pctrl_dev) {
dev_err(dev, "failed to register pinctrl driver\n");
return -EINVAL;
}
return 0;
}