[PATCH 2/3] pinctrl: nsp: add gpio-a driver support for Broadcom NSP SoC

From: Yendapally Reddy Dhananjaya Reddy
Date: Tue Dec 01 2015 - 23:47:14 EST


This adds the initial support of the Broadcom NSP gpio-a driver.

Signed-off-by: Yendapally Reddy Dhananjaya Reddy <yrdreddy@xxxxxxxxxxxx>
---
drivers/pinctrl/bcm/Kconfig | 17 +
drivers/pinctrl/bcm/Makefile | 1 +
drivers/pinctrl/bcm/pinctrl-nsp-gpio.c | 749 +++++++++++++++++++++++++++++++++
3 files changed, 767 insertions(+)
create mode 100644 drivers/pinctrl/bcm/pinctrl-nsp-gpio.c

diff --git a/drivers/pinctrl/bcm/Kconfig b/drivers/pinctrl/bcm/Kconfig
index cd11d4d..1a8c837 100644
--- a/drivers/pinctrl/bcm/Kconfig
+++ b/drivers/pinctrl/bcm/Kconfig
@@ -54,3 +54,20 @@ config PINCTRL_CYGNUS_MUX
The Broadcom Cygnus IOMUX driver supports group based IOMUX
configuration, with the exception that certain individual pins
can be overrided to GPIO function
+
+config PINCTRL_NSP_GPIO
+ bool "Broadcom NSP GPIO (with PINCONF) driver"
+ depends on OF_GPIO && (ARCH_BCM_NSP || COMPILE_TEST)
+ select GPIOLIB_IRQCHIP
+ select PINCONF
+ select GENERIC_PINCONF
+ default ARCH_BCM_NSP
+ help
+ Say yes here to enable the Broadcom NSP GPIO driver.
+
+ The Broadcom Northstar Plus SoC ChipcommonA GPIO controller is
+ supported by this driver.
+
+ The ChipcommonA GPIO controller support basic PINCONF functions such
+ as bias pull up, pull down, and drive strength configurations, when
+ these pins are muxed to GPIO.
diff --git a/drivers/pinctrl/bcm/Makefile b/drivers/pinctrl/bcm/Makefile
index 2b2f70e..2fb1ed8 100644
--- a/drivers/pinctrl/bcm/Makefile
+++ b/drivers/pinctrl/bcm/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_PINCTRL_BCM281XX) += pinctrl-bcm281xx.o
obj-$(CONFIG_PINCTRL_BCM2835) += pinctrl-bcm2835.o
obj-$(CONFIG_PINCTRL_CYGNUS_GPIO) += pinctrl-cygnus-gpio.o
obj-$(CONFIG_PINCTRL_CYGNUS_MUX) += pinctrl-cygnus-mux.o
+obj-$(CONFIG_PINCTRL_NSP_GPIO) += pinctrl-nsp-gpio.o
diff --git a/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
new file mode 100644
index 0000000..06b7aaf
--- /dev/null
+++ b/drivers/pinctrl/bcm/pinctrl-nsp-gpio.c
@@ -0,0 +1,749 @@
+/*
+ * 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.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
+};
+
+static inline struct nsp_gpio *to_nsp_gpio(struct gpio_chip *gc)
+{
+ return container_of(gc, struct nsp_gpio, gc);
+}
+
+/*
+ * 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 = to_nsp_gpio(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 = to_nsp_gpio(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 = to_nsp_gpio(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 = to_nsp_gpio(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 = to_nsp_gpio(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_dt_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 i, offset, shift;
+ u32 val;
+ unsigned long flags;
+
+ 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 = pinctrl_register(pctldesc, chip->dev, 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->dev = 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);
+ set_irq_flags(irq, IRQF_VALID);
+ 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(gc);
+ 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);
--
2.1.0

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