linux/drivers/gpio/gpio-wcove.c
Andy Shevchenko 0c3b532ad3 gpio: wcove: Use -ENOTSUPP consistently
The GPIO library expects the drivers to return -ENOTSUPP in some
cases and not using analogue POSIX code. Make the driver to follow
this.

Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2024-04-05 20:12:03 +03:00

515 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Intel Whiskey Cove PMIC GPIO Driver
*
* This driver is written based on gpio-crystalcove.c
*
* Copyright (C) 2016 Intel Corporation. All rights reserved.
*/
#include <linux/bitops.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/mfd/intel_soc_pmic.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/seq_file.h>
/*
* Whiskey Cove PMIC has 13 physical GPIO pins divided into 3 banks:
* Bank 0: Pin 0 - 6
* Bank 1: Pin 7 - 10
* Bank 2: Pin 11 - 12
* Each pin has one output control register and one input control register.
*/
#define BANK0_NR_PINS 7
#define BANK1_NR_PINS 4
#define BANK2_NR_PINS 2
#define WCOVE_GPIO_NUM (BANK0_NR_PINS + BANK1_NR_PINS + BANK2_NR_PINS)
#define WCOVE_VGPIO_NUM 94
/* GPIO output control registers (one per pin): 0x4e44 - 0x4e50 */
#define GPIO_OUT_CTRL_BASE 0x4e44
/* GPIO input control registers (one per pin): 0x4e51 - 0x4e5d */
#define GPIO_IN_CTRL_BASE 0x4e51
/*
* GPIO interrupts are organized in two groups:
* Group 0: Bank 0 pins (Pin 0 - 6)
* Group 1: Bank 1 and Bank 2 pins (Pin 7 - 12)
* Each group has two registers (one bit per pin): status and mask.
*/
#define GROUP0_NR_IRQS 7
#define GROUP1_NR_IRQS 6
#define IRQ_MASK_BASE 0x4e19
#define IRQ_STATUS_BASE 0x4e0b
#define GPIO_IRQ0_MASK GENMASK(6, 0)
#define GPIO_IRQ1_MASK GENMASK(5, 0)
#define UPDATE_IRQ_TYPE BIT(0)
#define UPDATE_IRQ_MASK BIT(1)
#define CTLI_INTCNT_DIS (0 << 1)
#define CTLI_INTCNT_NE (1 << 1)
#define CTLI_INTCNT_PE (2 << 1)
#define CTLI_INTCNT_BE (3 << 1)
#define CTLO_DIR_IN (0 << 5)
#define CTLO_DIR_OUT (1 << 5)
#define CTLO_DRV_MASK (1 << 4)
#define CTLO_DRV_OD (0 << 4)
#define CTLO_DRV_CMOS (1 << 4)
#define CTLO_DRV_REN (1 << 3)
#define CTLO_RVAL_2KDOWN (0 << 1)
#define CTLO_RVAL_2KUP (1 << 1)
#define CTLO_RVAL_50KDOWN (2 << 1)
#define CTLO_RVAL_50KUP (3 << 1)
#define CTLO_INPUT_SET (CTLO_DRV_CMOS | CTLO_DRV_REN | CTLO_RVAL_2KUP)
#define CTLO_OUTPUT_SET (CTLO_DIR_OUT | CTLO_INPUT_SET)
enum ctrl_register {
CTRL_IN,
CTRL_OUT,
IRQ_STATUS,
IRQ_MASK,
};
/*
* struct wcove_gpio - Whiskey Cove GPIO controller
* @buslock: for bus lock/sync and unlock.
* @chip: the abstract gpio_chip structure.
* @dev: the gpio device
* @regmap: the regmap from the parent device.
* @regmap_irq_chip: the regmap of the gpio irq chip.
* @update: pending IRQ setting update, to be written to the chip upon unlock.
* @intcnt: the Interrupt Detect value to be written.
* @set_irq_mask: true if the IRQ mask needs to be set, false to clear.
*/
struct wcove_gpio {
struct mutex buslock;
struct gpio_chip chip;
struct device *dev;
struct regmap *regmap;
struct regmap_irq_chip_data *regmap_irq_chip;
int update;
int intcnt;
bool set_irq_mask;
};
static inline int to_reg(int gpio, enum ctrl_register type)
{
unsigned int reg = type == CTRL_IN ? GPIO_IN_CTRL_BASE : GPIO_OUT_CTRL_BASE;
if (gpio >= WCOVE_GPIO_NUM)
return -ENOTSUPP;
return reg + gpio;
}
static inline int to_ireg(int gpio, enum ctrl_register type, unsigned int *mask)
{
unsigned int reg = type == IRQ_STATUS ? IRQ_STATUS_BASE : IRQ_MASK_BASE;
if (gpio < GROUP0_NR_IRQS) {
reg += 0;
*mask = BIT(gpio);
} else {
reg += 1;
*mask = BIT(gpio - GROUP0_NR_IRQS);
}
return reg;
}
static void wcove_update_irq_mask(struct wcove_gpio *wg, irq_hw_number_t gpio)
{
unsigned int mask, reg = to_ireg(gpio, IRQ_MASK, &mask);
if (wg->set_irq_mask)
regmap_set_bits(wg->regmap, reg, mask);
else
regmap_clear_bits(wg->regmap, reg, mask);
}
static void wcove_update_irq_ctrl(struct wcove_gpio *wg, irq_hw_number_t gpio)
{
int reg = to_reg(gpio, CTRL_IN);
regmap_update_bits(wg->regmap, reg, CTLI_INTCNT_BE, wg->intcnt);
}
static int wcove_gpio_dir_in(struct gpio_chip *chip, unsigned int gpio)
{
struct wcove_gpio *wg = gpiochip_get_data(chip);
int reg = to_reg(gpio, CTRL_OUT);
if (reg < 0)
return 0;
return regmap_write(wg->regmap, reg, CTLO_INPUT_SET);
}
static int wcove_gpio_dir_out(struct gpio_chip *chip, unsigned int gpio,
int value)
{
struct wcove_gpio *wg = gpiochip_get_data(chip);
int reg = to_reg(gpio, CTRL_OUT);
if (reg < 0)
return 0;
return regmap_write(wg->regmap, reg, CTLO_OUTPUT_SET | value);
}
static int wcove_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio)
{
struct wcove_gpio *wg = gpiochip_get_data(chip);
unsigned int val;
int ret, reg = to_reg(gpio, CTRL_OUT);
if (reg < 0)
return GPIO_LINE_DIRECTION_OUT;
ret = regmap_read(wg->regmap, reg, &val);
if (ret)
return ret;
if (val & CTLO_DIR_OUT)
return GPIO_LINE_DIRECTION_OUT;
return GPIO_LINE_DIRECTION_IN;
}
static int wcove_gpio_get(struct gpio_chip *chip, unsigned int gpio)
{
struct wcove_gpio *wg = gpiochip_get_data(chip);
unsigned int val;
int ret, reg = to_reg(gpio, CTRL_IN);
if (reg < 0)
return 0;
ret = regmap_read(wg->regmap, reg, &val);
if (ret)
return ret;
return val & 0x1;
}
static void wcove_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
{
struct wcove_gpio *wg = gpiochip_get_data(chip);
int reg = to_reg(gpio, CTRL_OUT);
if (reg < 0)
return;
if (value)
regmap_set_bits(wg->regmap, reg, 1);
else
regmap_clear_bits(wg->regmap, reg, 1);
}
static int wcove_gpio_set_config(struct gpio_chip *chip, unsigned int gpio,
unsigned long config)
{
struct wcove_gpio *wg = gpiochip_get_data(chip);
int reg = to_reg(gpio, CTRL_OUT);
if (reg < 0)
return 0;
switch (pinconf_to_config_param(config)) {
case PIN_CONFIG_DRIVE_OPEN_DRAIN:
return regmap_update_bits(wg->regmap, reg, CTLO_DRV_MASK,
CTLO_DRV_OD);
case PIN_CONFIG_DRIVE_PUSH_PULL:
return regmap_update_bits(wg->regmap, reg, CTLO_DRV_MASK,
CTLO_DRV_CMOS);
default:
break;
}
return -ENOTSUPP;
}
static int wcove_irq_type(struct irq_data *data, unsigned int type)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct wcove_gpio *wg = gpiochip_get_data(chip);
irq_hw_number_t gpio = irqd_to_hwirq(data);
if (gpio >= WCOVE_GPIO_NUM)
return 0;
switch (type) {
case IRQ_TYPE_NONE:
wg->intcnt = CTLI_INTCNT_DIS;
break;
case IRQ_TYPE_EDGE_BOTH:
wg->intcnt = CTLI_INTCNT_BE;
break;
case IRQ_TYPE_EDGE_RISING:
wg->intcnt = CTLI_INTCNT_PE;
break;
case IRQ_TYPE_EDGE_FALLING:
wg->intcnt = CTLI_INTCNT_NE;
break;
default:
return -EINVAL;
}
wg->update |= UPDATE_IRQ_TYPE;
return 0;
}
static void wcove_bus_lock(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct wcove_gpio *wg = gpiochip_get_data(chip);
mutex_lock(&wg->buslock);
}
static void wcove_bus_sync_unlock(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct wcove_gpio *wg = gpiochip_get_data(chip);
irq_hw_number_t gpio = irqd_to_hwirq(data);
if (wg->update & UPDATE_IRQ_TYPE)
wcove_update_irq_ctrl(wg, gpio);
if (wg->update & UPDATE_IRQ_MASK)
wcove_update_irq_mask(wg, gpio);
wg->update = 0;
mutex_unlock(&wg->buslock);
}
static void wcove_irq_unmask(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct wcove_gpio *wg = gpiochip_get_data(chip);
irq_hw_number_t gpio = irqd_to_hwirq(data);
if (gpio >= WCOVE_GPIO_NUM)
return;
gpiochip_enable_irq(chip, gpio);
wg->set_irq_mask = false;
wg->update |= UPDATE_IRQ_MASK;
}
static void wcove_irq_mask(struct irq_data *data)
{
struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
struct wcove_gpio *wg = gpiochip_get_data(chip);
irq_hw_number_t gpio = irqd_to_hwirq(data);
if (gpio >= WCOVE_GPIO_NUM)
return;
wg->set_irq_mask = true;
wg->update |= UPDATE_IRQ_MASK;
gpiochip_disable_irq(chip, gpio);
}
static const struct irq_chip wcove_irqchip = {
.name = "Whiskey Cove",
.irq_mask = wcove_irq_mask,
.irq_unmask = wcove_irq_unmask,
.irq_set_type = wcove_irq_type,
.irq_bus_lock = wcove_bus_lock,
.irq_bus_sync_unlock = wcove_bus_sync_unlock,
.flags = IRQCHIP_IMMUTABLE,
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
static irqreturn_t wcove_gpio_irq_handler(int irq, void *data)
{
struct wcove_gpio *wg = (struct wcove_gpio *)data;
unsigned int virq, gpio;
unsigned long pending;
u8 p[2];
if (regmap_bulk_read(wg->regmap, IRQ_STATUS_BASE, p, 2)) {
dev_err(wg->dev, "Failed to read irq status register\n");
return IRQ_NONE;
}
pending = (p[0] & GPIO_IRQ0_MASK) | ((p[1] & GPIO_IRQ1_MASK) << 7);
if (!pending)
return IRQ_NONE;
/* Iterate until no interrupt is pending */
while (pending) {
/* One iteration is for all pending bits */
for_each_set_bit(gpio, &pending, WCOVE_GPIO_NUM) {
unsigned int mask, reg = to_ireg(gpio, IRQ_STATUS, &mask);
virq = irq_find_mapping(wg->chip.irq.domain, gpio);
handle_nested_irq(virq);
regmap_set_bits(wg->regmap, reg, mask);
}
/* Next iteration */
if (regmap_bulk_read(wg->regmap, IRQ_STATUS_BASE, p, 2)) {
dev_err(wg->dev, "Failed to read irq status\n");
break;
}
pending = (p[0] & GPIO_IRQ0_MASK) | ((p[1] & GPIO_IRQ1_MASK) << 7);
}
return IRQ_HANDLED;
}
static void wcove_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
{
unsigned int ctlo, ctli, irq_mask, irq_status;
struct wcove_gpio *wg = gpiochip_get_data(chip);
int gpio, mask, ret = 0;
for (gpio = 0; gpio < WCOVE_GPIO_NUM; gpio++) {
ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &ctlo);
ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &ctli);
if (ret) {
dev_err(wg->dev, "Failed to read registers: CTRL out/in\n");
break;
}
ret += regmap_read(wg->regmap, to_ireg(gpio, IRQ_MASK, &mask), &irq_mask);
ret += regmap_read(wg->regmap, to_ireg(gpio, IRQ_STATUS, &mask), &irq_status);
if (ret) {
dev_err(wg->dev, "Failed to read registers: IRQ status/mask\n");
break;
}
seq_printf(s, " gpio-%-2d %s %s %s %s ctlo=%2x,%s %s\n",
gpio, ctlo & CTLO_DIR_OUT ? "out" : "in ",
ctli & 0x1 ? "hi" : "lo",
ctli & CTLI_INTCNT_NE ? "fall" : " ",
ctli & CTLI_INTCNT_PE ? "rise" : " ",
ctlo,
irq_mask & mask ? "mask " : "unmask",
irq_status & mask ? "pending" : " ");
}
}
static int wcove_gpio_probe(struct platform_device *pdev)
{
struct intel_soc_pmic *pmic;
struct wcove_gpio *wg;
int virq, ret, irq;
struct device *dev;
struct gpio_irq_chip *girq;
/*
* This gpio platform device is created by a mfd device (see
* drivers/mfd/intel_soc_pmic_bxtwc.c for details). Information
* shared by all sub-devices created by the mfd device, the regmap
* pointer for instance, is stored as driver data of the mfd device
* driver.
*/
pmic = dev_get_drvdata(pdev->dev.parent);
if (!pmic)
return -ENODEV;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return irq;
dev = &pdev->dev;
wg = devm_kzalloc(dev, sizeof(*wg), GFP_KERNEL);
if (!wg)
return -ENOMEM;
wg->regmap_irq_chip = pmic->irq_chip_data;
platform_set_drvdata(pdev, wg);
mutex_init(&wg->buslock);
wg->chip.label = KBUILD_MODNAME;
wg->chip.direction_input = wcove_gpio_dir_in;
wg->chip.direction_output = wcove_gpio_dir_out;
wg->chip.get_direction = wcove_gpio_get_direction;
wg->chip.get = wcove_gpio_get;
wg->chip.set = wcove_gpio_set;
wg->chip.set_config = wcove_gpio_set_config;
wg->chip.base = -1;
wg->chip.ngpio = WCOVE_VGPIO_NUM;
wg->chip.can_sleep = true;
wg->chip.parent = pdev->dev.parent;
wg->chip.dbg_show = wcove_gpio_dbg_show;
wg->dev = dev;
wg->regmap = pmic->regmap;
virq = regmap_irq_get_virq(wg->regmap_irq_chip, irq);
if (virq < 0) {
dev_err(dev, "Failed to get virq by irq %d\n", irq);
return virq;
}
girq = &wg->chip.irq;
gpio_irq_chip_set_chip(girq, &wcove_irqchip);
/* This will let us handle the parent IRQ in the driver */
girq->parent_handler = NULL;
girq->num_parents = 0;
girq->parents = NULL;
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_simple_irq;
girq->threaded = true;
ret = devm_request_threaded_irq(dev, virq, NULL, wcove_gpio_irq_handler,
IRQF_ONESHOT, pdev->name, wg);
if (ret) {
dev_err(dev, "Failed to request irq %d\n", virq);
return ret;
}
ret = devm_gpiochip_add_data(dev, &wg->chip, wg);
if (ret) {
dev_err(dev, "Failed to add gpiochip: %d\n", ret);
return ret;
}
/* Enable GPIO0 interrupts */
ret = regmap_clear_bits(wg->regmap, IRQ_MASK_BASE + 0, GPIO_IRQ0_MASK);
if (ret)
return ret;
/* Enable GPIO1 interrupts */
ret = regmap_clear_bits(wg->regmap, IRQ_MASK_BASE + 1, GPIO_IRQ1_MASK);
if (ret)
return ret;
return 0;
}
/*
* Whiskey Cove PMIC itself is a analog device(but with digital control
* interface) providing power management support for other devices in
* the accompanied SoC, so we have no .pm for Whiskey Cove GPIO driver.
*/
static struct platform_driver wcove_gpio_driver = {
.driver = {
.name = "bxt_wcove_gpio",
},
.probe = wcove_gpio_probe,
};
module_platform_driver(wcove_gpio_driver);
MODULE_AUTHOR("Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com>");
MODULE_AUTHOR("Bin Gao <bin.gao@intel.com>");
MODULE_DESCRIPTION("Intel Whiskey Cove GPIO Driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:bxt_wcove_gpio");