pinctrl-zx.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2017 Sanechips Technology Co., Ltd.
* Copyright 2017 Linaro Ltd.
*/
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinmux.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "../core.h"
#include "../pinctrl-utils.h"
#include "../pinmux.h"
#include "pinctrl-zx.h"
#define ZX_PULL_DOWN BIT(0)
#define ZX_PULL_UP BIT(1)
#define ZX_INPUT_ENABLE BIT(3)
#define ZX_DS_SHIFT 4
#define ZX_DS_MASK (0x7 << ZX_DS_SHIFT)
#define ZX_DS_VALUE(x) (((x) << ZX_DS_SHIFT) & ZX_DS_MASK)
#define ZX_SLEW BIT(8)
struct zx_pinctrl {
struct pinctrl_dev *pctldev;
struct device *dev;
void __iomem *base;
void __iomem *aux_base;
spinlock_t lock;
struct zx_pinctrl_soc_info *info;
};
static int zx_dt_node_to_map(struct pinctrl_dev *pctldev,
struct device_node *np_config,
struct pinctrl_map **map, u32 *num_maps)
{
return pinconf_generic_dt_node_to_map(pctldev, np_config, map,
num_maps, PIN_MAP_TYPE_INVALID);
}
static const struct pinctrl_ops zx_pinctrl_ops = {
.dt_node_to_map = zx_dt_node_to_map,
.dt_free_map = pinctrl_utils_free_map,
.get_groups_count = pinctrl_generic_get_group_count,
.get_group_name = pinctrl_generic_get_group_name,
.get_group_pins = pinctrl_generic_get_group_pins,
};
#define NONAON_MVAL 2
static int zx_set_mux(struct pinctrl_dev *pctldev, unsigned int func_selector,
unsigned int group_selector)
{
struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
struct zx_pinctrl_soc_info *info = zpctl->info;
const struct pinctrl_pin_desc *pindesc = info->pins + group_selector;
struct zx_pin_data *data = pindesc->drv_data;
struct zx_mux_desc *mux;
u32 mask, offset, bitpos;
struct function_desc *func;
unsigned long flags;
u32 val, mval;
/* Skip reserved pin */
if (!data)
return -EINVAL;
mux = data->muxes;
mask = (1 << data->width) - 1;
offset = data->offset;
bitpos = data->bitpos;
func = pinmux_generic_get_function(pctldev, func_selector);
if (!func)
return -EINVAL;
while (mux->name) {
if (strcmp(mux->name, func->name) == 0)
break;
mux++;
}
/* Found mux value to be written */
mval = mux->muxval;
spin_lock_irqsave(&zpctl->lock, flags);
if (data->aon_pin) {
/*
* It's an AON pin, whose mux register offset and bit position
* can be caluculated from pin number. Each register covers 16
* pins, and each pin occupies 2 bits.
*/
u16 aoffset = pindesc->number / 16 * 4;
u16 abitpos = (pindesc->number % 16) * 2;
if (mval & AON_MUX_FLAG) {
/*
* This is a mux value that needs to be written into
* AON pinmux register. Write it and then we're done.
*/
val = readl(zpctl->aux_base + aoffset);
val &= ~(0x3 << abitpos);
val |= (mval & 0x3) << abitpos;
writel(val, zpctl->aux_base + aoffset);
} else {
/*
* It's a mux value that needs to be written into TOP
* pinmux register.
*/
val = readl(zpctl->base + offset);
val &= ~(mask << bitpos);
val |= (mval & mask) << bitpos;
writel(val, zpctl->base + offset);
/*
* In this case, the AON pinmux register needs to be
* set up to select non-AON function.
*/
val = readl(zpctl->aux_base + aoffset);
val &= ~(0x3 << abitpos);
val |= NONAON_MVAL << abitpos;
writel(val, zpctl->aux_base + aoffset);
}
} else {
/*
* This is a TOP pin, and we only need to set up TOP pinmux
* register and then we're done with it.
*/
val = readl(zpctl->base + offset);
val &= ~(mask << bitpos);
val |= (mval & mask) << bitpos;
writel(val, zpctl->base + offset);
}
spin_unlock_irqrestore(&zpctl->lock, flags);
return 0;
}
static const struct pinmux_ops zx_pinmux_ops = {
.get_functions_count = pinmux_generic_get_function_count,
.get_function_name = pinmux_generic_get_function_name,
.get_function_groups = pinmux_generic_get_function_groups,
.set_mux = zx_set_mux,
};
static int zx_pin_config_get(struct pinctrl_dev *pctldev, unsigned int pin,
unsigned long *config)
{
struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
struct zx_pinctrl_soc_info *info = zpctl->info;
const struct pinctrl_pin_desc *pindesc = info->pins + pin;
struct zx_pin_data *data = pindesc->drv_data;
enum pin_config_param param = pinconf_to_config_param(*config);
u32 val;
/* Skip reserved pin */
if (!data)
return -EINVAL;
val = readl(zpctl->aux_base + data->coffset);
val = val >> data->cbitpos;
switch (param) {
case PIN_CONFIG_BIAS_PULL_DOWN:
val &= ZX_PULL_DOWN;
val = !!val;
if (val == 0)
return -EINVAL;
break;
case PIN_CONFIG_BIAS_PULL_UP:
val &= ZX_PULL_UP;
val = !!val;
if (val == 0)
return -EINVAL;
break;
case PIN_CONFIG_INPUT_ENABLE:
val &= ZX_INPUT_ENABLE;
val = !!val;
if (val == 0)
return -EINVAL;
break;
case PIN_CONFIG_DRIVE_STRENGTH:
val &= ZX_DS_MASK;
val = val >> ZX_DS_SHIFT;
break;
case PIN_CONFIG_SLEW_RATE:
val &= ZX_SLEW;
val = !!val;
break;
default:
return -ENOTSUPP;
}
*config = pinconf_to_config_packed(param, val);
return 0;
}
static int zx_pin_config_set(struct pinctrl_dev *pctldev, unsigned int pin,
unsigned long *configs, unsigned int num_configs)
{
struct zx_pinctrl *zpctl = pinctrl_dev_get_drvdata(pctldev);
struct zx_pinctrl_soc_info *info = zpctl->info;
const struct pinctrl_pin_desc *pindesc = info->pins + pin;
struct zx_pin_data *data = pindesc->drv_data;
enum pin_config_param param;
u32 val, arg;
int i;
/* Skip reserved pin */
if (!data)
return -EINVAL;
val = readl(zpctl->aux_base + data->coffset);
for (i = 0; i < num_configs; i++) {
param = pinconf_to_config_param(configs[i]);
arg = pinconf_to_config_argument(configs[i]);
switch (param) {
case PIN_CONFIG_BIAS_PULL_DOWN:
val |= ZX_PULL_DOWN << data->cbitpos;
break;
case PIN_CONFIG_BIAS_PULL_UP:
val |= ZX_PULL_UP << data->cbitpos;
break;
case PIN_CONFIG_INPUT_ENABLE:
val |= ZX_INPUT_ENABLE << data->cbitpos;
break;
case PIN_CONFIG_DRIVE_STRENGTH:
val &= ~(ZX_DS_MASK << data->cbitpos);
val |= ZX_DS_VALUE(arg) << data->cbitpos;
break;
case PIN_CONFIG_SLEW_RATE:
if (arg)
val |= ZX_SLEW << data->cbitpos;
else
val &= ~ZX_SLEW << data->cbitpos;
break;
default:
return -ENOTSUPP;
}
}
writel(val, zpctl->aux_base + data->coffset);
return 0;
}
static const struct pinconf_ops zx_pinconf_ops = {
.pin_config_set = zx_pin_config_set,
.pin_config_get = zx_pin_config_get,
.is_generic = true,
};
static int zx_pinctrl_build_state(struct platform_device *pdev)
{
struct zx_pinctrl *zpctl = platform_get_drvdata(pdev);
struct zx_pinctrl_soc_info *info = zpctl->info;
struct pinctrl_dev *pctldev = zpctl->pctldev;
struct function_desc *functions;
int nfunctions;
struct group_desc *groups;
int ngroups;
int i;
/* Every single pin composes a group */
ngroups = info->npins;
groups = devm_kcalloc(&pdev->dev, ngroups, sizeof(*groups),
GFP_KERNEL);
if (!groups)
return -ENOMEM;
for (i = 0; i < ngroups; i++) {
const struct pinctrl_pin_desc *pindesc = info->pins + i;
struct group_desc *group = groups + i;
group->name = pindesc->name;
group->pins = (int *) &pindesc->number;
group->num_pins = 1;
radix_tree_insert(&pctldev->pin_group_tree, i, group);
}
pctldev->num_groups = ngroups;
/* Build function list from pin mux functions */
functions = kcalloc(info->npins, sizeof(*functions), GFP_KERNEL);
if (!functions)
return -ENOMEM;
nfunctions = 0;
for (i = 0; i < info->npins; i++) {
const struct pinctrl_pin_desc *pindesc = info->pins + i;
struct zx_pin_data *data = pindesc->drv_data;
struct zx_mux_desc *mux;
/* Reserved pins do not have a drv_data at all */
if (!data)
continue;
/* Loop over all muxes for the pin */
mux = data->muxes;
while (mux->name) {
struct function_desc *func = functions;
/* Search function list for given mux */
while (func->name) {
if (strcmp(mux->name, func->name) == 0) {
/* Function exists */
func->num_group_names++;
break;
}
func++;
}
if (!func->name) {
/* New function */
func->name = mux->name;
func->num_group_names = 1;
radix_tree_insert(&pctldev->pin_function_tree,
nfunctions++, func);
}
mux++;
}
}
pctldev->num_functions = nfunctions;
functions = krealloc(functions, nfunctions * sizeof(*functions),
GFP_KERNEL);
/* Find pin groups for every single function */
for (i = 0; i < info->npins; i++) {
const struct pinctrl_pin_desc *pindesc = info->pins + i;
struct zx_pin_data *data = pindesc->drv_data;
struct zx_mux_desc *mux;
if (!data)
continue;
mux = data->muxes;
while (mux->name) {
struct function_desc *func;
const char **group;
int j;
/* Find function for given mux */
for (j = 0; j < nfunctions; j++)
if (strcmp(functions[j].name, mux->name) == 0)
break;
func = functions + j;
if (!func->group_names) {
func->group_names = devm_kcalloc(&pdev->dev,
func->num_group_names,
sizeof(*func->group_names),
GFP_KERNEL);
if (!func->group_names) {
kfree(functions);
return -ENOMEM;
}
}
group = func->group_names;
while (*group)
group++;
*group = pindesc->name;
mux++;
}
}
return 0;
}
int zx_pinctrl_init(struct platform_device *pdev,
struct zx_pinctrl_soc_info *info)
{
struct pinctrl_desc *pctldesc;
struct zx_pinctrl *zpctl;
struct device_node *np;
int ret;
zpctl = devm_kzalloc(&pdev->dev, sizeof(*zpctl), GFP_KERNEL);
if (!zpctl)
return -ENOMEM;
spin_lock_init(&zpctl->lock);
zpctl->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(zpctl->base))
return PTR_ERR(zpctl->base);
np = of_parse_phandle(pdev->dev.of_node, "zte,auxiliary-controller", 0);
if (!np) {
dev_err(&pdev->dev, "failed to find auxiliary controller\n");
return -ENODEV;
}
zpctl->aux_base = of_iomap(np, 0);
of_node_put(np);
if (!zpctl->aux_base)
return -ENOMEM;
zpctl->dev = &pdev->dev;
zpctl->info = info;
pctldesc = devm_kzalloc(&pdev->dev, sizeof(*pctldesc), GFP_KERNEL);
if (!pctldesc)
return -ENOMEM;
pctldesc->name = dev_name(&pdev->dev);
pctldesc->owner = THIS_MODULE;
pctldesc->pins = info->pins;
pctldesc->npins = info->npins;
pctldesc->pctlops = &zx_pinctrl_ops;
pctldesc->pmxops = &zx_pinmux_ops;
pctldesc->confops = &zx_pinconf_ops;
zpctl->pctldev = devm_pinctrl_register(&pdev->dev, pctldesc, zpctl);
if (IS_ERR(zpctl->pctldev)) {
ret = PTR_ERR(zpctl->pctldev);
dev_err(&pdev->dev, "failed to register pinctrl: %d\n", ret);
return ret;
}
platform_set_drvdata(pdev, zpctl);
ret = zx_pinctrl_build_state(pdev);
if (ret) {
dev_err(&pdev->dev, "failed to build state: %d\n", ret);
return ret;
}
dev_info(&pdev->dev, "initialized pinctrl driver\n");
return 0;
}