linux/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c

745 lines
19 KiB
C

/*
* Copyright (C) 2015 Broadcom Corporation
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation version 2.
*
* This program is distributed "as is" WITHOUT ANY WARRANTY of any
* kind, whether express or implied; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* This file contains the Broadcom Northstar Plus (NSP) GPIO driver that
* supports the chipCommonA GPIO controller. Basic PINCONF such as bias,
* pull up/down, slew and drive strength are also supported in this driver.
*
* Pins from the chipCommonA GPIO can be individually muxed to GPIO function,
* through the interaction with the NSP IOMUX controller.
*/
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/kernel.h>
#include <linux/of_address.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/pinctrl/pinconf.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinctrl.h>
#include <linux/slab.h>
#include "../pinctrl-utils.h"
#define NSP_CHIP_A_INT_STATUS 0x00
#define NSP_CHIP_A_INT_MASK 0x04
#define NSP_GPIO_DATA_IN 0x40
#define NSP_GPIO_DATA_OUT 0x44
#define NSP_GPIO_OUT_EN 0x48
#define NSP_GPIO_INT_POLARITY 0x50
#define NSP_GPIO_INT_MASK 0x54
#define NSP_GPIO_EVENT 0x58
#define NSP_GPIO_EVENT_INT_MASK 0x5c
#define NSP_GPIO_EVENT_INT_POLARITY 0x64
#define NSP_CHIP_A_GPIO_INT_BIT 0x01
/* I/O parameters offset for chipcommon A GPIO */
#define NSP_GPIO_DRV_CTRL 0x00
#define NSP_GPIO_HYSTERESIS_EN 0x10
#define NSP_GPIO_SLEW_RATE_EN 0x14
#define NSP_PULL_UP_EN 0x18
#define NSP_PULL_DOWN_EN 0x1c
#define GPIO_DRV_STRENGTH_BITS 0x03
/*
* nsp GPIO core
*
* @dev: pointer to device
* @base: I/O register base for nsp GPIO controller
* @io_ctrl: I/O register base for PINCONF support outside the GPIO block
* @gc: GPIO chip
* @pctl: pointer to pinctrl_dev
* @pctldesc: pinctrl descriptor
* @irq_domain: pointer to irq domain
* @lock: lock to protect access to I/O registers
*/
struct nsp_gpio {
struct device *dev;
void __iomem *base;
void __iomem *io_ctrl;
struct gpio_chip gc;
struct pinctrl_dev *pctl;
struct pinctrl_desc pctldesc;
struct irq_domain *irq_domain;
spinlock_t lock;
};
enum base_type {
REG,
IO_CTRL
};
/*
* Mapping from PINCONF pins to GPIO pins is 1-to-1
*/
static inline unsigned nsp_pin_to_gpio(unsigned pin)
{
return pin;
}
/*
* nsp_set_bit - set or clear one bit (corresponding to the GPIO pin) in a
* nsp GPIO register
*
* @nsp_gpio: nsp GPIO device
* @base_type: reg base to modify
* @reg: register offset
* @gpio: GPIO pin
* @set: set or clear
*/
static inline void nsp_set_bit(struct nsp_gpio *chip, enum base_type address,
unsigned int reg, unsigned gpio, bool set)
{
u32 val;
void __iomem *base_address;
if (address == IO_CTRL)
base_address = chip->io_ctrl;
else
base_address = chip->base;
val = readl(base_address + reg);
if (set)
val |= BIT(gpio);
else
val &= ~BIT(gpio);
writel(val, base_address + reg);
}
/*
* nsp_get_bit - get one bit (corresponding to the GPIO pin) in a
* nsp GPIO register
*/
static inline bool nsp_get_bit(struct nsp_gpio *chip, enum base_type address,
unsigned int reg, unsigned gpio)
{
if (address == IO_CTRL)
return !!(readl(chip->io_ctrl + reg) & BIT(gpio));
else
return !!(readl(chip->base + reg) & BIT(gpio));
}
static irqreturn_t nsp_gpio_irq_handler(int irq, void *data)
{
struct nsp_gpio *chip = (struct nsp_gpio *)data;
struct gpio_chip gc = chip->gc;
int bit;
unsigned long int_bits = 0;
u32 int_status;
/* go through the entire GPIOs and handle all interrupts */
int_status = readl(chip->base + NSP_CHIP_A_INT_STATUS);
if (int_status & NSP_CHIP_A_GPIO_INT_BIT) {
unsigned int event, level;
/* Get level and edge interrupts */
event = readl(chip->base + NSP_GPIO_EVENT_INT_MASK) &
readl(chip->base + NSP_GPIO_EVENT);
level = readl(chip->base + NSP_GPIO_DATA_IN) ^
readl(chip->base + NSP_GPIO_INT_POLARITY);
level &= readl(chip->base + NSP_GPIO_INT_MASK);
int_bits = level | event;
for_each_set_bit(bit, &int_bits, gc.ngpio) {
/*
* Clear the interrupt before invoking the
* handler, so we do not leave any window
*/
writel(BIT(bit), chip->base + NSP_GPIO_EVENT);
generic_handle_irq(
irq_linear_revmap(chip->irq_domain, bit));
}
}
return int_bits ? IRQ_HANDLED : IRQ_NONE;
}
static void nsp_gpio_irq_ack(struct irq_data *d)
{
struct nsp_gpio *chip = irq_data_get_irq_chip_data(d);
unsigned gpio = d->hwirq;
u32 val = BIT(gpio);
u32 trigger_type;
trigger_type = irq_get_trigger_type(d->irq);
if (trigger_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
nsp_set_bit(chip, REG, NSP_GPIO_EVENT, gpio, val);
}
/*
* nsp_gpio_irq_set_mask - mask/unmask a GPIO interrupt
*
* @d: IRQ chip data
* @unmask: mask/unmask GPIO interrupt
*/
static void nsp_gpio_irq_set_mask(struct irq_data *d, bool unmask)
{
struct nsp_gpio *chip = irq_data_get_irq_chip_data(d);
unsigned gpio = d->hwirq;
u32 trigger_type;
trigger_type = irq_get_trigger_type(d->irq);
if (trigger_type & (IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
nsp_set_bit(chip, REG, NSP_GPIO_EVENT_INT_MASK, gpio, unmask);
else
nsp_set_bit(chip, REG, NSP_GPIO_INT_MASK, gpio, unmask);
}
static void nsp_gpio_irq_mask(struct irq_data *d)
{
struct nsp_gpio *chip = irq_data_get_irq_chip_data(d);
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
nsp_gpio_irq_set_mask(d, false);
spin_unlock_irqrestore(&chip->lock, flags);
}
static void nsp_gpio_irq_unmask(struct irq_data *d)
{
struct nsp_gpio *chip = irq_data_get_irq_chip_data(d);
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
nsp_gpio_irq_set_mask(d, true);
spin_unlock_irqrestore(&chip->lock, flags);
}
static int nsp_gpio_irq_set_type(struct irq_data *d, unsigned int type)
{
struct nsp_gpio *chip = irq_data_get_irq_chip_data(d);
unsigned gpio = d->hwirq;
bool level_low;
bool falling;
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
falling = nsp_get_bit(chip, REG, NSP_GPIO_EVENT_INT_POLARITY, gpio);
level_low = nsp_get_bit(chip, REG, NSP_GPIO_INT_POLARITY, gpio);
switch (type & IRQ_TYPE_SENSE_MASK) {
case IRQ_TYPE_EDGE_RISING:
falling = false;
break;
case IRQ_TYPE_EDGE_FALLING:
falling = true;
break;
case IRQ_TYPE_LEVEL_HIGH:
level_low = false;
break;
case IRQ_TYPE_LEVEL_LOW:
level_low = true;
break;
default:
dev_err(chip->dev, "invalid GPIO IRQ type 0x%x\n",
type);
spin_unlock_irqrestore(&chip->lock, flags);
return -EINVAL;
}
nsp_set_bit(chip, REG, NSP_GPIO_EVENT_INT_POLARITY, gpio, falling);
nsp_set_bit(chip, REG, NSP_GPIO_INT_POLARITY, gpio, level_low);
spin_unlock_irqrestore(&chip->lock, flags);
dev_dbg(chip->dev, "gpio:%u level_low:%s falling:%s\n", gpio,
level_low ? "true" : "false", falling ? "true" : "false");
return 0;
}
static struct irq_chip nsp_gpio_irq_chip = {
.name = "gpio-a",
.irq_enable = nsp_gpio_irq_unmask,
.irq_disable = nsp_gpio_irq_mask,
.irq_ack = nsp_gpio_irq_ack,
.irq_mask = nsp_gpio_irq_mask,
.irq_unmask = nsp_gpio_irq_unmask,
.irq_set_type = nsp_gpio_irq_set_type,
};
/*
* Request the nsp IOMUX pinmux controller to mux individual pins to GPIO
*/
static int nsp_gpio_request(struct gpio_chip *gc, unsigned offset)
{
unsigned gpio = gc->base + offset;
return pinctrl_request_gpio(gpio);
}
static void nsp_gpio_free(struct gpio_chip *gc, unsigned offset)
{
unsigned gpio = gc->base + offset;
pinctrl_free_gpio(gpio);
}
static int nsp_gpio_direction_input(struct gpio_chip *gc, unsigned gpio)
{
struct nsp_gpio *chip = gpiochip_get_data(gc);
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, false);
spin_unlock_irqrestore(&chip->lock, flags);
dev_dbg(chip->dev, "gpio:%u set input\n", gpio);
return 0;
}
static int nsp_gpio_direction_output(struct gpio_chip *gc, unsigned gpio,
int val)
{
struct nsp_gpio *chip = gpiochip_get_data(gc);
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, true);
nsp_set_bit(chip, REG, NSP_GPIO_DATA_OUT, gpio, !!(val));
spin_unlock_irqrestore(&chip->lock, flags);
dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val);
return 0;
}
static void nsp_gpio_set(struct gpio_chip *gc, unsigned gpio, int val)
{
struct nsp_gpio *chip = gpiochip_get_data(gc);
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
nsp_set_bit(chip, REG, NSP_GPIO_DATA_OUT, gpio, !!(val));
spin_unlock_irqrestore(&chip->lock, flags);
dev_dbg(chip->dev, "gpio:%u set, value:%d\n", gpio, val);
}
static int nsp_gpio_get(struct gpio_chip *gc, unsigned gpio)
{
struct nsp_gpio *chip = gpiochip_get_data(gc);
return !!(readl(chip->base + NSP_GPIO_DATA_IN) & BIT(gpio));
}
static int nsp_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
{
struct nsp_gpio *chip = gpiochip_get_data(gc);
return irq_linear_revmap(chip->irq_domain, offset);
}
static int nsp_get_groups_count(struct pinctrl_dev *pctldev)
{
return 1;
}
/*
* Only one group: "gpio_grp", since this local pinctrl device only performs
* GPIO specific PINCONF configurations
*/
static const char *nsp_get_group_name(struct pinctrl_dev *pctldev,
unsigned selector)
{
return "gpio_grp";
}
static const struct pinctrl_ops nsp_pctrl_ops = {
.get_groups_count = nsp_get_groups_count,
.get_group_name = nsp_get_group_name,
.dt_node_to_map = pinconf_generic_dt_node_to_map_pin,
.dt_free_map = pinctrl_utils_free_map,
};
static int nsp_gpio_set_slew(struct nsp_gpio *chip, unsigned gpio, u16 slew)
{
if (slew)
nsp_set_bit(chip, IO_CTRL, NSP_GPIO_SLEW_RATE_EN, gpio, true);
else
nsp_set_bit(chip, IO_CTRL, NSP_GPIO_SLEW_RATE_EN, gpio, false);
return 0;
}
static int nsp_gpio_set_pull(struct nsp_gpio *chip, unsigned gpio,
bool pull_up, bool pull_down)
{
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
nsp_set_bit(chip, IO_CTRL, NSP_PULL_DOWN_EN, gpio, pull_down);
nsp_set_bit(chip, IO_CTRL, NSP_PULL_UP_EN, gpio, pull_up);
spin_unlock_irqrestore(&chip->lock, flags);
dev_dbg(chip->dev, "gpio:%u set pullup:%d pulldown: %d\n",
gpio, pull_up, pull_down);
return 0;
}
static void nsp_gpio_get_pull(struct nsp_gpio *chip, unsigned gpio,
bool *pull_up, bool *pull_down)
{
unsigned long flags;
spin_lock_irqsave(&chip->lock, flags);
*pull_up = nsp_get_bit(chip, IO_CTRL, NSP_PULL_UP_EN, gpio);
*pull_down = nsp_get_bit(chip, IO_CTRL, NSP_PULL_DOWN_EN, gpio);
spin_unlock_irqrestore(&chip->lock, flags);
}
static int nsp_gpio_set_strength(struct nsp_gpio *chip, unsigned gpio,
u16 strength)
{
u32 offset, shift, i;
u32 val;
unsigned long flags;
/* make sure drive strength is supported */
if (strength < 2 || strength > 16 || (strength % 2))
return -ENOTSUPP;
shift = gpio;
offset = NSP_GPIO_DRV_CTRL;
dev_dbg(chip->dev, "gpio:%u set drive strength:%d mA\n", gpio,
strength);
spin_lock_irqsave(&chip->lock, flags);
strength = (strength / 2) - 1;
for (i = GPIO_DRV_STRENGTH_BITS; i > 0; i--) {
val = readl(chip->io_ctrl + offset);
val &= ~BIT(shift);
val |= ((strength >> (i-1)) & 0x1) << shift;
writel(val, chip->io_ctrl + offset);
offset += 4;
}
spin_unlock_irqrestore(&chip->lock, flags);
return 0;
}
static int nsp_gpio_get_strength(struct nsp_gpio *chip, unsigned gpio,
u16 *strength)
{
unsigned int offset, shift;
u32 val;
unsigned long flags;
int i;
offset = NSP_GPIO_DRV_CTRL;
shift = gpio;
spin_lock_irqsave(&chip->lock, flags);
*strength = 0;
for (i = (GPIO_DRV_STRENGTH_BITS - 1); i >= 0; i--) {
val = readl(chip->io_ctrl + offset) & BIT(shift);
val >>= shift;
*strength += (val << i);
offset += 4;
}
/* convert to mA */
*strength = (*strength + 1) * 2;
spin_unlock_irqrestore(&chip->lock, flags);
return 0;
}
int nsp_pin_config_group_get(struct pinctrl_dev *pctldev, unsigned selector,
unsigned long *config)
{
return 0;
}
int nsp_pin_config_group_set(struct pinctrl_dev *pctldev, unsigned selector,
unsigned long *configs, unsigned num_configs)
{
return 0;
}
static int nsp_pin_config_get(struct pinctrl_dev *pctldev, unsigned pin,
unsigned long *config)
{
struct nsp_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
enum pin_config_param param = pinconf_to_config_param(*config);
unsigned int gpio;
u16 arg = 0;
bool pull_up, pull_down;
int ret;
gpio = nsp_pin_to_gpio(pin);
switch (param) {
case PIN_CONFIG_BIAS_DISABLE:
nsp_gpio_get_pull(chip, gpio, &pull_up, &pull_down);
if ((pull_up == false) && (pull_down == false))
return 0;
else
return -EINVAL;
case PIN_CONFIG_BIAS_PULL_UP:
nsp_gpio_get_pull(chip, gpio, &pull_up, &pull_down);
if (pull_up)
return 0;
else
return -EINVAL;
case PIN_CONFIG_BIAS_PULL_DOWN:
nsp_gpio_get_pull(chip, gpio, &pull_up, &pull_down);
if (pull_down)
return 0;
else
return -EINVAL;
case PIN_CONFIG_DRIVE_STRENGTH:
ret = nsp_gpio_get_strength(chip, gpio, &arg);
if (ret)
return ret;
*config = pinconf_to_config_packed(param, arg);
return 0;
default:
return -ENOTSUPP;
}
}
static int nsp_pin_config_set(struct pinctrl_dev *pctldev, unsigned pin,
unsigned long *configs, unsigned num_configs)
{
struct nsp_gpio *chip = pinctrl_dev_get_drvdata(pctldev);
enum pin_config_param param;
u16 arg;
unsigned int i, gpio;
int ret = -ENOTSUPP;
gpio = nsp_pin_to_gpio(pin);
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_DISABLE:
ret = nsp_gpio_set_pull(chip, gpio, false, false);
if (ret < 0)
goto out;
break;
case PIN_CONFIG_BIAS_PULL_UP:
ret = nsp_gpio_set_pull(chip, gpio, true, false);
if (ret < 0)
goto out;
break;
case PIN_CONFIG_BIAS_PULL_DOWN:
ret = nsp_gpio_set_pull(chip, gpio, false, true);
if (ret < 0)
goto out;
break;
case PIN_CONFIG_DRIVE_STRENGTH:
ret = nsp_gpio_set_strength(chip, gpio, arg);
if (ret < 0)
goto out;
break;
case PIN_CONFIG_SLEW_RATE:
ret = nsp_gpio_set_slew(chip, gpio, arg);
if (ret < 0)
goto out;
break;
default:
dev_err(chip->dev, "invalid configuration\n");
return -ENOTSUPP;
}
}
out:
return ret;
}
static const struct pinconf_ops nsp_pconf_ops = {
.is_generic = true,
.pin_config_get = nsp_pin_config_get,
.pin_config_set = nsp_pin_config_set,
.pin_config_group_get = nsp_pin_config_group_get,
.pin_config_group_set = nsp_pin_config_group_set,
};
/*
* NSP GPIO controller supports some PINCONF related configurations such as
* pull up, pull down, slew and drive strength, when the pin is configured
* to GPIO.
*
* Here a local pinctrl device is created with simple 1-to-1 pin mapping to the
* local GPIO pins
*/
static int nsp_gpio_register_pinconf(struct nsp_gpio *chip)
{
struct pinctrl_desc *pctldesc = &chip->pctldesc;
struct pinctrl_pin_desc *pins;
struct gpio_chip *gc = &chip->gc;
int i;
pins = devm_kcalloc(chip->dev, gc->ngpio, sizeof(*pins), GFP_KERNEL);
if (!pins)
return -ENOMEM;
for (i = 0; i < gc->ngpio; i++) {
pins[i].number = i;
pins[i].name = devm_kasprintf(chip->dev, GFP_KERNEL,
"gpio-%d", i);
if (!pins[i].name)
return -ENOMEM;
}
pctldesc->name = dev_name(chip->dev);
pctldesc->pctlops = &nsp_pctrl_ops;
pctldesc->pins = pins;
pctldesc->npins = gc->ngpio;
pctldesc->confops = &nsp_pconf_ops;
chip->pctl = devm_pinctrl_register(chip->dev, pctldesc, chip);
if (IS_ERR(chip->pctl)) {
dev_err(chip->dev, "unable to register pinctrl device\n");
return PTR_ERR(chip->pctl);
}
return 0;
}
static const struct of_device_id nsp_gpio_of_match[] = {
{.compatible = "brcm,nsp-gpio-a",},
{}
};
static int nsp_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct resource *res;
struct nsp_gpio *chip;
struct gpio_chip *gc;
u32 val, count;
int irq, ret;
if (of_property_read_u32(pdev->dev.of_node, "ngpios", &val)) {
dev_err(&pdev->dev, "Missing ngpios OF property\n");
return -ENODEV;
}
chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
if (!chip)
return -ENOMEM;
chip->dev = dev;
platform_set_drvdata(pdev, chip);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
chip->base = devm_ioremap_resource(dev, res);
if (IS_ERR(chip->base)) {
dev_err(dev, "unable to map I/O memory\n");
return PTR_ERR(chip->base);
}
res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
chip->io_ctrl = devm_ioremap_resource(dev, res);
if (IS_ERR(chip->io_ctrl)) {
dev_err(dev, "unable to map I/O memory\n");
return PTR_ERR(chip->io_ctrl);
}
spin_lock_init(&chip->lock);
gc = &chip->gc;
gc->base = -1;
gc->can_sleep = false;
gc->ngpio = val;
gc->label = dev_name(dev);
gc->parent = dev;
gc->of_node = dev->of_node;
gc->request = nsp_gpio_request;
gc->free = nsp_gpio_free;
gc->direction_input = nsp_gpio_direction_input;
gc->direction_output = nsp_gpio_direction_output;
gc->set = nsp_gpio_set;
gc->get = nsp_gpio_get;
gc->to_irq = nsp_gpio_to_irq;
/* optional GPIO interrupt support */
irq = platform_get_irq(pdev, 0);
if (irq > 0) {
/* Create irq domain so that each pin can be assigned an IRQ.*/
chip->irq_domain = irq_domain_add_linear(gc->of_node, gc->ngpio,
&irq_domain_simple_ops,
chip);
if (!chip->irq_domain) {
dev_err(&pdev->dev, "Couldn't allocate IRQ domain\n");
return -ENXIO;
}
/* Map each gpio to an IRQ and set the handler for gpiolib. */
for (count = 0; count < gc->ngpio; count++) {
int irq = irq_create_mapping(chip->irq_domain, count);
irq_set_chip_and_handler(irq, &nsp_gpio_irq_chip,
handle_simple_irq);
irq_set_chip_data(irq, chip);
}
/* Install ISR for this GPIO controller. */
ret = devm_request_irq(&pdev->dev, irq, nsp_gpio_irq_handler,
IRQF_SHARED, "gpio-a", chip);
if (ret) {
dev_err(&pdev->dev, "Unable to request IRQ%d: %d\n",
irq, ret);
goto err_rm_gpiochip;
}
val = readl(chip->base + NSP_CHIP_A_INT_MASK);
val = val | NSP_CHIP_A_GPIO_INT_BIT;
writel(val, (chip->base + NSP_CHIP_A_INT_MASK));
}
ret = gpiochip_add_data(gc, chip);
if (ret < 0) {
dev_err(dev, "unable to add GPIO chip\n");
return ret;
}
ret = nsp_gpio_register_pinconf(chip);
if (ret) {
dev_err(dev, "unable to register pinconf\n");
goto err_rm_gpiochip;
}
return 0;
err_rm_gpiochip:
gpiochip_remove(gc);
return ret;
}
static struct platform_driver nsp_gpio_driver = {
.driver = {
.name = "nsp-gpio-a",
.of_match_table = nsp_gpio_of_match,
},
.probe = nsp_gpio_probe,
};
static int __init nsp_gpio_init(void)
{
return platform_driver_probe(&nsp_gpio_driver, nsp_gpio_probe);
}
arch_initcall_sync(nsp_gpio_init);