kernel-fxtec-pro1x/drivers/pinctrl/spear/pinctrl-spear.c
Devendra Naga 8003ae335a pinctrl/pinctrl-spear: remove IS_ERR checking of pmx->pctl
pinctrl_register returns a pointer of struct type struct pinctrl_dev,
if successfully registered to pinctrl subsystem, otherwise returns
NULL, and there wont' be any pointers which are not dereferencible.

They are not type of pointer addresses but are kind of error
codes rather actual addresses, but are a kind of return
codes of functions returning integer types.

return -ENODEV if device registration fails.

Signed-off-by: Devendra Naga <devendra.aaru@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2012-07-03 21:51:08 +02:00

354 lines
8.4 KiB
C

/*
* Driver for the ST Microelectronics SPEAr pinmux
*
* Copyright (C) 2012 ST Microelectronics
* Viresh Kumar <viresh.linux@gmail.com>
*
* Inspired from:
* - U300 Pinctl drivers
* - Tegra Pinctl drivers
*
* 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/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/pinctrl/machine.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "pinctrl-spear.h"
#define DRIVER_NAME "spear-pinmux"
static inline u32 pmx_readl(struct spear_pmx *pmx, u32 reg)
{
return readl_relaxed(pmx->vbase + reg);
}
static inline void pmx_writel(struct spear_pmx *pmx, u32 val, u32 reg)
{
writel_relaxed(val, pmx->vbase + reg);
}
static int set_mode(struct spear_pmx *pmx, int mode)
{
struct spear_pmx_mode *pmx_mode = NULL;
int i;
u32 val;
if (!pmx->machdata->pmx_modes || !pmx->machdata->npmx_modes)
return -EINVAL;
for (i = 0; i < pmx->machdata->npmx_modes; i++) {
if (pmx->machdata->pmx_modes[i]->mode == (1 << mode)) {
pmx_mode = pmx->machdata->pmx_modes[i];
break;
}
}
if (!pmx_mode)
return -EINVAL;
val = pmx_readl(pmx, pmx_mode->reg);
val &= ~pmx_mode->mask;
val |= pmx_mode->val;
pmx_writel(pmx, val, pmx_mode->reg);
pmx->machdata->mode = pmx_mode->mode;
dev_info(pmx->dev, "Configured Mode: %s with id: %x\n\n",
pmx_mode->name ? pmx_mode->name : "no_name",
pmx_mode->reg);
return 0;
}
void __devinit pmx_init_addr(struct spear_pinctrl_machdata *machdata, u16 reg)
{
struct spear_pingroup *pgroup;
struct spear_modemux *modemux;
int i, j, group;
for (group = 0; group < machdata->ngroups; group++) {
pgroup = machdata->groups[group];
for (i = 0; i < pgroup->nmodemuxs; i++) {
modemux = &pgroup->modemuxs[i];
for (j = 0; j < modemux->nmuxregs; j++)
if (modemux->muxregs[j].reg == 0xFFFF)
modemux->muxregs[j].reg = reg;
}
}
}
static int spear_pinctrl_get_groups_cnt(struct pinctrl_dev *pctldev)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
return pmx->machdata->ngroups;
}
static const char *spear_pinctrl_get_group_name(struct pinctrl_dev *pctldev,
unsigned group)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
return pmx->machdata->groups[group]->name;
}
static int spear_pinctrl_get_group_pins(struct pinctrl_dev *pctldev,
unsigned group, const unsigned **pins, unsigned *num_pins)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
*pins = pmx->machdata->groups[group]->pins;
*num_pins = pmx->machdata->groups[group]->npins;
return 0;
}
static void spear_pinctrl_pin_dbg_show(struct pinctrl_dev *pctldev,
struct seq_file *s, unsigned offset)
{
seq_printf(s, " " DRIVER_NAME);
}
int spear_pinctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
struct device_node *np_config,
struct pinctrl_map **map, unsigned *num_maps)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
struct device_node *np;
struct property *prop;
const char *function, *group;
int ret, index = 0, count = 0;
/* calculate number of maps required */
for_each_child_of_node(np_config, np) {
ret = of_property_read_string(np, "st,function", &function);
if (ret < 0)
return ret;
ret = of_property_count_strings(np, "st,pins");
if (ret < 0)
return ret;
count += ret;
}
if (!count) {
dev_err(pmx->dev, "No child nodes passed via DT\n");
return -ENODEV;
}
*map = kzalloc(sizeof(**map) * count, GFP_KERNEL);
if (!*map)
return -ENOMEM;
for_each_child_of_node(np_config, np) {
of_property_read_string(np, "st,function", &function);
of_property_for_each_string(np, "st,pins", prop, group) {
(*map)[index].type = PIN_MAP_TYPE_MUX_GROUP;
(*map)[index].data.mux.group = group;
(*map)[index].data.mux.function = function;
index++;
}
}
*num_maps = count;
return 0;
}
void spear_pinctrl_dt_free_map(struct pinctrl_dev *pctldev,
struct pinctrl_map *map, unsigned num_maps)
{
kfree(map);
}
static struct pinctrl_ops spear_pinctrl_ops = {
.get_groups_count = spear_pinctrl_get_groups_cnt,
.get_group_name = spear_pinctrl_get_group_name,
.get_group_pins = spear_pinctrl_get_group_pins,
.pin_dbg_show = spear_pinctrl_pin_dbg_show,
.dt_node_to_map = spear_pinctrl_dt_node_to_map,
.dt_free_map = spear_pinctrl_dt_free_map,
};
static int spear_pinctrl_get_funcs_count(struct pinctrl_dev *pctldev)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
return pmx->machdata->nfunctions;
}
static const char *spear_pinctrl_get_func_name(struct pinctrl_dev *pctldev,
unsigned function)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
return pmx->machdata->functions[function]->name;
}
static int spear_pinctrl_get_func_groups(struct pinctrl_dev *pctldev,
unsigned function, const char *const **groups,
unsigned * const ngroups)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
*groups = pmx->machdata->functions[function]->groups;
*ngroups = pmx->machdata->functions[function]->ngroups;
return 0;
}
static int spear_pinctrl_endisable(struct pinctrl_dev *pctldev,
unsigned function, unsigned group, bool enable)
{
struct spear_pmx *pmx = pinctrl_dev_get_drvdata(pctldev);
const struct spear_pingroup *pgroup;
const struct spear_modemux *modemux;
struct spear_muxreg *muxreg;
u32 val, temp;
int i, j;
bool found = false;
pgroup = pmx->machdata->groups[group];
for (i = 0; i < pgroup->nmodemuxs; i++) {
modemux = &pgroup->modemuxs[i];
/* SoC have any modes */
if (pmx->machdata->modes_supported) {
if (!(pmx->machdata->mode & modemux->modes))
continue;
}
found = true;
for (j = 0; j < modemux->nmuxregs; j++) {
muxreg = &modemux->muxregs[j];
val = pmx_readl(pmx, muxreg->reg);
val &= ~muxreg->mask;
if (enable)
temp = muxreg->val;
else
temp = ~muxreg->val;
val |= temp;
pmx_writel(pmx, val, muxreg->reg);
}
}
if (!found) {
dev_err(pmx->dev, "pinmux group: %s not supported\n",
pgroup->name);
return -ENODEV;
}
return 0;
}
static int spear_pinctrl_enable(struct pinctrl_dev *pctldev, unsigned function,
unsigned group)
{
return spear_pinctrl_endisable(pctldev, function, group, true);
}
static void spear_pinctrl_disable(struct pinctrl_dev *pctldev,
unsigned function, unsigned group)
{
spear_pinctrl_endisable(pctldev, function, group, false);
}
static struct pinmux_ops spear_pinmux_ops = {
.get_functions_count = spear_pinctrl_get_funcs_count,
.get_function_name = spear_pinctrl_get_func_name,
.get_function_groups = spear_pinctrl_get_func_groups,
.enable = spear_pinctrl_enable,
.disable = spear_pinctrl_disable,
};
static struct pinctrl_desc spear_pinctrl_desc = {
.name = DRIVER_NAME,
.pctlops = &spear_pinctrl_ops,
.pmxops = &spear_pinmux_ops,
.owner = THIS_MODULE,
};
int __devinit spear_pinctrl_probe(struct platform_device *pdev,
struct spear_pinctrl_machdata *machdata)
{
struct device_node *np = pdev->dev.of_node;
struct resource *res;
struct spear_pmx *pmx;
if (!machdata)
return -ENODEV;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -EINVAL;
pmx = devm_kzalloc(&pdev->dev, sizeof(*pmx), GFP_KERNEL);
if (!pmx) {
dev_err(&pdev->dev, "Can't alloc spear_pmx\n");
return -ENOMEM;
}
pmx->vbase = devm_ioremap(&pdev->dev, res->start, resource_size(res));
if (!pmx->vbase) {
dev_err(&pdev->dev, "Couldn't ioremap at index 0\n");
return -ENODEV;
}
pmx->dev = &pdev->dev;
pmx->machdata = machdata;
/* configure mode, if supported by SoC */
if (machdata->modes_supported) {
int mode = 0;
if (of_property_read_u32(np, "st,pinmux-mode", &mode)) {
dev_err(&pdev->dev, "OF: pinmux mode not passed\n");
return -EINVAL;
}
if (set_mode(pmx, mode)) {
dev_err(&pdev->dev, "OF: Couldn't configure mode: %x\n",
mode);
return -EINVAL;
}
}
platform_set_drvdata(pdev, pmx);
spear_pinctrl_desc.pins = machdata->pins;
spear_pinctrl_desc.npins = machdata->npins;
pmx->pctl = pinctrl_register(&spear_pinctrl_desc, &pdev->dev, pmx);
if (!pmx->pctl) {
dev_err(&pdev->dev, "Couldn't register pinctrl driver\n");
return -ENODEV;
}
return 0;
}
int __devexit spear_pinctrl_remove(struct platform_device *pdev)
{
struct spear_pmx *pmx = platform_get_drvdata(pdev);
pinctrl_unregister(pmx->pctl);
return 0;
}