diff options
Diffstat (limited to 'drivers/pinctrl/bcm/pinctrl-nsp-gpio.c')
-rw-r--r-- | drivers/pinctrl/bcm/pinctrl-nsp-gpio.c | 712 |
1 files changed, 712 insertions, 0 deletions
diff --git a/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c new file mode 100644 index 000000000..3c792bf03 --- /dev/null +++ b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c @@ -0,0 +1,712 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2014-2017 Broadcom + +/* + * 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 + * @lock: lock to protect access to I/O registers + */ +struct nsp_gpio { + struct device *dev; + void __iomem *base; + void __iomem *io_ctrl; + struct irq_chip irqchip; + struct gpio_chip gc; + struct pinctrl_dev *pctl; + struct pinctrl_desc pctldesc; + raw_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 gpio_chip *gc = (struct gpio_chip *)data; + struct nsp_gpio *chip = gpiochip_get_data(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) + generic_handle_domain_irq(gc->irq.domain, bit); + } + + return int_bits ? IRQ_HANDLED : IRQ_NONE; +} + +static void nsp_gpio_irq_ack(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct nsp_gpio *chip = gpiochip_get_data(gc); + 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)) + writel(val, chip->base + NSP_GPIO_EVENT); +} + +/* + * 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 gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct nsp_gpio *chip = gpiochip_get_data(gc); + 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 gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct nsp_gpio *chip = gpiochip_get_data(gc); + unsigned long flags; + + raw_spin_lock_irqsave(&chip->lock, flags); + nsp_gpio_irq_set_mask(d, false); + raw_spin_unlock_irqrestore(&chip->lock, flags); +} + +static void nsp_gpio_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct nsp_gpio *chip = gpiochip_get_data(gc); + unsigned long flags; + + raw_spin_lock_irqsave(&chip->lock, flags); + nsp_gpio_irq_set_mask(d, true); + raw_spin_unlock_irqrestore(&chip->lock, flags); +} + +static int nsp_gpio_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct nsp_gpio *chip = gpiochip_get_data(gc); + unsigned gpio = d->hwirq; + bool level_low; + bool falling; + unsigned long flags; + + raw_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); + raw_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); + + if (type & IRQ_TYPE_EDGE_BOTH) + irq_set_handler_locked(d, handle_edge_irq); + else + irq_set_handler_locked(d, handle_level_irq); + + raw_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 int nsp_gpio_direction_input(struct gpio_chip *gc, unsigned gpio) +{ + struct nsp_gpio *chip = gpiochip_get_data(gc); + unsigned long flags; + + raw_spin_lock_irqsave(&chip->lock, flags); + nsp_set_bit(chip, REG, NSP_GPIO_OUT_EN, gpio, false); + raw_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; + + raw_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)); + raw_spin_unlock_irqrestore(&chip->lock, flags); + + dev_dbg(chip->dev, "gpio:%u set output, value:%d\n", gpio, val); + return 0; +} + +static int nsp_gpio_get_direction(struct gpio_chip *gc, unsigned gpio) +{ + struct nsp_gpio *chip = gpiochip_get_data(gc); + unsigned long flags; + int val; + + raw_spin_lock_irqsave(&chip->lock, flags); + val = nsp_get_bit(chip, REG, NSP_GPIO_OUT_EN, gpio); + raw_spin_unlock_irqrestore(&chip->lock, flags); + + return !val; +} + +static void nsp_gpio_set(struct gpio_chip *gc, unsigned gpio, int val) +{ + struct nsp_gpio *chip = gpiochip_get_data(gc); + unsigned long flags; + + raw_spin_lock_irqsave(&chip->lock, flags); + nsp_set_bit(chip, REG, NSP_GPIO_DATA_OUT, gpio, !!(val)); + raw_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_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, u32 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; + + raw_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); + raw_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; + + raw_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); + raw_spin_unlock_irqrestore(&chip->lock, flags); +} + +static int nsp_gpio_set_strength(struct nsp_gpio *chip, unsigned gpio, + u32 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); + raw_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; + } + raw_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; + + raw_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; + raw_spin_unlock_irqrestore(&chip->lock, flags); + + return 0; +} + +static int nsp_pin_config_group_get(struct pinctrl_dev *pctldev, + unsigned selector, + unsigned long *config) +{ + return 0; +} + +static 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; + u32 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 nsp_gpio *chip; + struct gpio_chip *gc; + u32 val; + 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); + + chip->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(chip->base)) { + dev_err(dev, "unable to map I/O memory\n"); + return PTR_ERR(chip->base); + } + + chip->io_ctrl = devm_platform_ioremap_resource(pdev, 1); + if (IS_ERR(chip->io_ctrl)) { + dev_err(dev, "unable to map I/O memory\n"); + return PTR_ERR(chip->io_ctrl); + } + + raw_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->request = gpiochip_generic_request; + gc->free = gpiochip_generic_free; + gc->direction_input = nsp_gpio_direction_input; + gc->direction_output = nsp_gpio_direction_output; + gc->get_direction = nsp_gpio_get_direction; + gc->set = nsp_gpio_set; + gc->get = nsp_gpio_get; + + /* optional GPIO interrupt support */ + irq = platform_get_irq(pdev, 0); + if (irq > 0) { + struct gpio_irq_chip *girq; + struct irq_chip *irqc; + + irqc = &chip->irqchip; + irqc->name = "gpio-a"; + irqc->irq_ack = nsp_gpio_irq_ack; + irqc->irq_mask = nsp_gpio_irq_mask; + irqc->irq_unmask = nsp_gpio_irq_unmask; + irqc->irq_set_type = nsp_gpio_irq_set_type; + + 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)); + + /* Install ISR for this GPIO controller. */ + ret = devm_request_irq(dev, irq, nsp_gpio_irq_handler, + IRQF_SHARED, "gpio-a", &chip->gc); + if (ret) { + dev_err(&pdev->dev, "Unable to request IRQ%d: %d\n", + irq, ret); + return ret; + } + + girq = &chip->gc.irq; + girq->chip = irqc; + /* 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_bad_irq; + } + + ret = devm_gpiochip_add_data(dev, 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"); + return ret; + } + + return 0; +} + +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_register(&nsp_gpio_driver); +} +arch_initcall_sync(nsp_gpio_init); |