diff options
Diffstat (limited to 'drivers/gpio/gpio-wcove.c')
| -rw-r--r-- | drivers/gpio/gpio-wcove.c | 470 |
1 files changed, 470 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-wcove.c b/drivers/gpio/gpio-wcove.c new file mode 100644 index 000000000000..d0ddba7a9d08 --- /dev/null +++ b/drivers/gpio/gpio-wcove.c @@ -0,0 +1,470 @@ +/* + * Intel Whiskey Cove PMIC GPIO Driver + * + * This driver is written based on gpio-crystalcove.c + * + * Copyright (C) 2016 Intel Corporation. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/bitops.h> +#include <linux/module.h> +#include <linux/interrupt.h> +#include <linux/gpio/driver.h> +#include <linux/mfd/intel_soc_pmic.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 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, +}; + +/* + * 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 unsigned int to_reg(int gpio, enum ctrl_register reg_type) +{ + unsigned int reg; + int bank; + + if (gpio < BANK0_NR_PINS) + bank = 0; + else if (gpio < BANK0_NR_PINS + BANK1_NR_PINS) + bank = 1; + else + bank = 2; + + if (reg_type == CTRL_IN) + reg = GPIO_IN_CTRL_BASE + bank; + else + reg = GPIO_OUT_CTRL_BASE + bank; + + return reg; +} + +static void wcove_update_irq_mask(struct wcove_gpio *wg, int gpio) +{ + unsigned int reg, mask; + + if (gpio < GROUP0_NR_IRQS) { + reg = IRQ_MASK_BASE; + mask = BIT(gpio % GROUP0_NR_IRQS); + } else { + reg = IRQ_MASK_BASE + 1; + mask = BIT((gpio - GROUP0_NR_IRQS) % GROUP1_NR_IRQS); + } + + if (wg->set_irq_mask) + regmap_update_bits(wg->regmap, reg, mask, mask); + else + regmap_update_bits(wg->regmap, reg, mask, 0); +} + +static void wcove_update_irq_ctrl(struct wcove_gpio *wg, int gpio) +{ + unsigned 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); + + return regmap_write(wg->regmap, to_reg(gpio, CTRL_OUT), + 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); + + return regmap_write(wg->regmap, to_reg(gpio, CTRL_OUT), + 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; + + ret = regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &val); + if (ret) + return ret; + + return !(val & CTLO_DIR_OUT); +} + +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; + + ret = regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &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); + + if (value) + regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 1, 1); + else + regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), 1, 0); +} + +static int wcove_gpio_set_single_ended(struct gpio_chip *chip, + unsigned int gpio, + enum single_ended_mode mode) +{ + struct wcove_gpio *wg = gpiochip_get_data(chip); + + switch (mode) { + case LINE_MODE_OPEN_DRAIN: + return regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), + CTLO_DRV_MASK, CTLO_DRV_OD); + case LINE_MODE_PUSH_PULL: + return regmap_update_bits(wg->regmap, to_reg(gpio, CTRL_OUT), + 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); + + 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); + int gpio = data->hwirq; + + 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); + + 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); + + wg->set_irq_mask = true; + wg->update |= UPDATE_IRQ_MASK; +} + +static 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, +}; + +static irqreturn_t wcove_gpio_irq_handler(int irq, void *data) +{ + struct wcove_gpio *wg = (struct wcove_gpio *)data; + unsigned int pending, virq, gpio, mask, offset; + 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] | (p[1] << 8); + 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, (const unsigned long *)&pending, + GROUP0_NR_IRQS) { + offset = (gpio > GROUP0_NR_IRQS) ? 1 : 0; + mask = (offset == 1) ? BIT(gpio - GROUP0_NR_IRQS) : + BIT(gpio); + virq = irq_find_mapping(wg->chip.irqdomain, gpio); + handle_nested_irq(virq); + regmap_update_bits(wg->regmap, IRQ_STATUS_BASE + offset, + mask, 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] | (p[1] << 8); + } + + 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, offset, group, ret = 0; + + for (gpio = 0; gpio < WCOVE_GPIO_NUM; gpio++) { + group = gpio < GROUP0_NR_IRQS ? 0 : 1; + ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_OUT), &ctlo); + ret += regmap_read(wg->regmap, to_reg(gpio, CTRL_IN), &ctli); + ret += regmap_read(wg->regmap, IRQ_MASK_BASE + group, + &irq_mask); + ret += regmap_read(wg->regmap, IRQ_STATUS_BASE + group, + &irq_status); + if (ret) { + pr_err("Failed to read registers: ctrl out/in or irq status/mask\n"); + break; + } + + offset = gpio % 8; + 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 & BIT(offset) ? "mask " : "unmask", + irq_status & BIT(offset) ? "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; + + /* + * 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_level2; + + 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_single_ended = wcove_gpio_set_single_ended, + 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; + + ret = devm_gpiochip_add_data(dev, &wg->chip, wg); + if (ret) { + dev_err(dev, "Failed to add gpiochip: %d\n", ret); + return ret; + } + + ret = gpiochip_irqchip_add(&wg->chip, &wcove_irqchip, 0, + handle_simple_irq, IRQ_TYPE_NONE); + if (ret) { + dev_err(dev, "Failed to add irqchip: %d\n", ret); + return ret; + } + + 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; + } + + 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; + } + + 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"); |