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path: root/drivers/gpio/gpio-tangier.c
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-rw-r--r--drivers/gpio/gpio-tangier.c536
1 files changed, 536 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tangier.c b/drivers/gpio/gpio-tangier.c
new file mode 100644
index 000000000000..e990781935ba
--- /dev/null
+++ b/drivers/gpio/gpio-tangier.c
@@ -0,0 +1,536 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Tangier GPIO driver
+ *
+ * Copyright (c) 2016, 2021, 2023 Intel Corporation.
+ *
+ * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ * Pandith N <pandith.n@intel.com>
+ * Raag Jadav <raag.jadav@intel.com>
+ */
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/pinctrl/pinconf-generic.h>
+#include <linux/spinlock.h>
+#include <linux/string_helpers.h>
+#include <linux/types.h>
+
+#include <linux/gpio/driver.h>
+
+#include "gpio-tangier.h"
+
+#define GCCR 0x000 /* Controller configuration */
+#define GPLR 0x004 /* Pin level r/o */
+#define GPDR 0x01c /* Pin direction */
+#define GPSR 0x034 /* Pin set w/o */
+#define GPCR 0x04c /* Pin clear w/o */
+#define GRER 0x064 /* Rising edge detect */
+#define GFER 0x07c /* Falling edge detect */
+#define GFBR 0x094 /* Glitch filter bypass */
+#define GIMR 0x0ac /* Interrupt mask */
+#define GISR 0x0c4 /* Interrupt source */
+#define GITR 0x300 /* Input type */
+#define GLPR 0x318 /* Level input polarity */
+
+/**
+ * struct tng_gpio_context - Context to be saved during suspend-resume
+ * @level: Pin level
+ * @gpdr: Pin direction
+ * @grer: Rising edge detect enable
+ * @gfer: Falling edge detect enable
+ * @gimr: Interrupt mask
+ * @gwmr: Wake mask
+ */
+struct tng_gpio_context {
+ u32 level;
+ u32 gpdr;
+ u32 grer;
+ u32 gfer;
+ u32 gimr;
+ u32 gwmr;
+};
+
+static void __iomem *gpio_reg(struct gpio_chip *chip, unsigned int offset,
+ unsigned int reg)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ u8 reg_offset = offset / 32;
+
+ return priv->reg_base + reg + reg_offset * 4;
+}
+
+static void __iomem *gpio_reg_and_bit(struct gpio_chip *chip, unsigned int offset,
+ unsigned int reg, u8 *bit)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ u8 reg_offset = offset / 32;
+ u8 shift = offset % 32;
+
+ *bit = shift;
+ return priv->reg_base + reg + reg_offset * 4;
+}
+
+static int tng_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+ void __iomem *gplr;
+ u8 shift;
+
+ gplr = gpio_reg_and_bit(chip, offset, GPLR, &shift);
+
+ return !!(readl(gplr) & BIT(shift));
+}
+
+static void tng_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ unsigned long flags;
+ void __iomem *reg;
+ u8 shift;
+
+ reg = gpio_reg_and_bit(chip, offset, value ? GPSR : GPCR, &shift);
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ writel(BIT(shift), reg);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static int tng_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ unsigned long flags;
+ void __iomem *gpdr;
+ u32 value;
+ u8 shift;
+
+ gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift);
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ value = readl(gpdr);
+ value &= ~BIT(shift);
+ writel(value, gpdr);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int tng_gpio_direction_output(struct gpio_chip *chip, unsigned int offset,
+ int value)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ unsigned long flags;
+ void __iomem *gpdr;
+ u8 shift;
+
+ gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift);
+ tng_gpio_set(chip, offset, value);
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ value = readl(gpdr);
+ value |= BIT(shift);
+ writel(value, gpdr);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int tng_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ void __iomem *gpdr;
+ u8 shift;
+
+ gpdr = gpio_reg_and_bit(chip, offset, GPDR, &shift);
+
+ if (readl(gpdr) & BIT(shift))
+ return GPIO_LINE_DIRECTION_OUT;
+
+ return GPIO_LINE_DIRECTION_IN;
+}
+
+static int tng_gpio_set_debounce(struct gpio_chip *chip, unsigned int offset,
+ unsigned int debounce)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ unsigned long flags;
+ void __iomem *gfbr;
+ u32 value;
+ u8 shift;
+
+ gfbr = gpio_reg_and_bit(chip, offset, GFBR, &shift);
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ value = readl(gfbr);
+ if (debounce)
+ value &= ~BIT(shift);
+ else
+ value |= BIT(shift);
+ writel(value, gfbr);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int tng_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
+ unsigned long config)
+{
+ u32 debounce;
+
+ switch (pinconf_to_config_param(config)) {
+ case PIN_CONFIG_BIAS_DISABLE:
+ case PIN_CONFIG_BIAS_PULL_UP:
+ case PIN_CONFIG_BIAS_PULL_DOWN:
+ return gpiochip_generic_config(chip, offset, config);
+ case PIN_CONFIG_INPUT_DEBOUNCE:
+ debounce = pinconf_to_config_argument(config);
+ return tng_gpio_set_debounce(chip, offset, debounce);
+ default:
+ return -ENOTSUPP;
+ }
+}
+
+static void tng_irq_ack(struct irq_data *d)
+{
+ struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
+ irq_hw_number_t gpio = irqd_to_hwirq(d);
+ unsigned long flags;
+ void __iomem *gisr;
+ u8 shift;
+
+ gisr = gpio_reg_and_bit(&priv->chip, gpio, GISR, &shift);
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+ writel(BIT(shift), gisr);
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void tng_irq_unmask_mask(struct tng_gpio *priv, u32 gpio, bool unmask)
+{
+ unsigned long flags;
+ void __iomem *gimr;
+ u32 value;
+ u8 shift;
+
+ gimr = gpio_reg_and_bit(&priv->chip, gpio, GIMR, &shift);
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ value = readl(gimr);
+ if (unmask)
+ value |= BIT(shift);
+ else
+ value &= ~BIT(shift);
+ writel(value, gimr);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+}
+
+static void tng_irq_mask(struct irq_data *d)
+{
+ struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
+ irq_hw_number_t gpio = irqd_to_hwirq(d);
+
+ tng_irq_unmask_mask(priv, gpio, false);
+ gpiochip_disable_irq(&priv->chip, gpio);
+}
+
+static void tng_irq_unmask(struct irq_data *d)
+{
+ struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
+ irq_hw_number_t gpio = irqd_to_hwirq(d);
+
+ gpiochip_enable_irq(&priv->chip, gpio);
+ tng_irq_unmask_mask(priv, gpio, true);
+}
+
+static int tng_irq_set_type(struct irq_data *d, unsigned int type)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct tng_gpio *priv = gpiochip_get_data(gc);
+ irq_hw_number_t gpio = irqd_to_hwirq(d);
+ void __iomem *grer = gpio_reg(&priv->chip, gpio, GRER);
+ void __iomem *gfer = gpio_reg(&priv->chip, gpio, GFER);
+ void __iomem *gitr = gpio_reg(&priv->chip, gpio, GITR);
+ void __iomem *glpr = gpio_reg(&priv->chip, gpio, GLPR);
+ u8 shift = gpio % 32;
+ unsigned long flags;
+ u32 value;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ value = readl(grer);
+ if (type & IRQ_TYPE_EDGE_RISING)
+ value |= BIT(shift);
+ else
+ value &= ~BIT(shift);
+ writel(value, grer);
+
+ value = readl(gfer);
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ value |= BIT(shift);
+ else
+ value &= ~BIT(shift);
+ writel(value, gfer);
+
+ /*
+ * To prevent glitches from triggering an unintended level interrupt,
+ * configure GLPR register first and then configure GITR.
+ */
+ value = readl(glpr);
+ if (type & IRQ_TYPE_LEVEL_LOW)
+ value |= BIT(shift);
+ else
+ value &= ~BIT(shift);
+ writel(value, glpr);
+
+ if (type & IRQ_TYPE_LEVEL_MASK) {
+ value = readl(gitr);
+ value |= BIT(shift);
+ writel(value, gitr);
+
+ irq_set_handler_locked(d, handle_level_irq);
+ } else if (type & IRQ_TYPE_EDGE_BOTH) {
+ value = readl(gitr);
+ value &= ~BIT(shift);
+ writel(value, gitr);
+
+ irq_set_handler_locked(d, handle_edge_irq);
+ }
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static int tng_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct tng_gpio *priv = gpiochip_get_data(gc);
+ irq_hw_number_t gpio = irqd_to_hwirq(d);
+ void __iomem *gwmr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwmr);
+ void __iomem *gwsr = gpio_reg(&priv->chip, gpio, priv->wake_regs.gwsr);
+ u8 shift = gpio % 32;
+ unsigned long flags;
+ u32 value;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ /* Clear the existing wake status */
+ writel(BIT(shift), gwsr);
+
+ value = readl(gwmr);
+ if (on)
+ value |= BIT(shift);
+ else
+ value &= ~BIT(shift);
+ writel(value, gwmr);
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ dev_dbg(priv->dev, "%s wake for gpio %lu\n", str_enable_disable(on), gpio);
+ return 0;
+}
+
+static const struct irq_chip tng_irqchip = {
+ .name = "gpio-tangier",
+ .irq_ack = tng_irq_ack,
+ .irq_mask = tng_irq_mask,
+ .irq_unmask = tng_irq_unmask,
+ .irq_set_type = tng_irq_set_type,
+ .irq_set_wake = tng_irq_set_wake,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+static void tng_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct tng_gpio *priv = gpiochip_get_data(gc);
+ struct irq_chip *irqchip = irq_desc_get_chip(desc);
+ unsigned long base, gpio;
+
+ chained_irq_enter(irqchip, desc);
+
+ /* Check GPIO controller to check which pin triggered the interrupt */
+ for (base = 0; base < priv->chip.ngpio; base += 32) {
+ void __iomem *gisr = gpio_reg(&priv->chip, base, GISR);
+ void __iomem *gimr = gpio_reg(&priv->chip, base, GIMR);
+ unsigned long pending, enabled;
+
+ pending = readl(gisr);
+ enabled = readl(gimr);
+
+ /* Only interrupts that are enabled */
+ pending &= enabled;
+
+ for_each_set_bit(gpio, &pending, 32)
+ generic_handle_domain_irq(gc->irq.domain, base + gpio);
+ }
+
+ chained_irq_exit(irqchip, desc);
+}
+
+static int tng_irq_init_hw(struct gpio_chip *chip)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ void __iomem *reg;
+ unsigned int base;
+
+ for (base = 0; base < priv->chip.ngpio; base += 32) {
+ /* Clear the rising-edge detect register */
+ reg = gpio_reg(&priv->chip, base, GRER);
+ writel(0, reg);
+
+ /* Clear the falling-edge detect register */
+ reg = gpio_reg(&priv->chip, base, GFER);
+ writel(0, reg);
+ }
+
+ return 0;
+}
+
+static int tng_gpio_add_pin_ranges(struct gpio_chip *chip)
+{
+ struct tng_gpio *priv = gpiochip_get_data(chip);
+ const struct tng_gpio_pinrange *range;
+ unsigned int i;
+ int ret;
+
+ for (i = 0; i < priv->pin_info.nranges; i++) {
+ range = &priv->pin_info.pin_ranges[i];
+ ret = gpiochip_add_pin_range(&priv->chip,
+ priv->pin_info.name,
+ range->gpio_base,
+ range->pin_base,
+ range->npins);
+ if (ret) {
+ dev_err(priv->dev, "failed to add GPIO pin range\n");
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+int devm_tng_gpio_probe(struct device *dev, struct tng_gpio *gpio)
+{
+ const struct tng_gpio_info *info = &gpio->info;
+ struct gpio_irq_chip *girq;
+ int ret;
+
+ gpio->ctx = devm_kcalloc(dev, DIV_ROUND_UP(info->ngpio, 32), sizeof(*gpio->ctx), GFP_KERNEL);
+ if (!gpio->ctx)
+ return -ENOMEM;
+
+ gpio->chip.label = dev_name(dev);
+ gpio->chip.parent = dev;
+ gpio->chip.request = gpiochip_generic_request;
+ gpio->chip.free = gpiochip_generic_free;
+ gpio->chip.direction_input = tng_gpio_direction_input;
+ gpio->chip.direction_output = tng_gpio_direction_output;
+ gpio->chip.get = tng_gpio_get;
+ gpio->chip.set = tng_gpio_set;
+ gpio->chip.get_direction = tng_gpio_get_direction;
+ gpio->chip.set_config = tng_gpio_set_config;
+ gpio->chip.base = info->base;
+ gpio->chip.ngpio = info->ngpio;
+ gpio->chip.can_sleep = false;
+ gpio->chip.add_pin_ranges = tng_gpio_add_pin_ranges;
+
+ raw_spin_lock_init(&gpio->lock);
+
+ girq = &gpio->chip.irq;
+ gpio_irq_chip_set_chip(girq, &tng_irqchip);
+ girq->init_hw = tng_irq_init_hw;
+ girq->parent_handler = tng_irq_handler;
+ girq->num_parents = 1;
+ girq->parents = devm_kcalloc(dev, girq->num_parents,
+ sizeof(*girq->parents), GFP_KERNEL);
+ if (!girq->parents)
+ return -ENOMEM;
+
+ girq->parents[0] = gpio->irq;
+ girq->first = info->first;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_bad_irq;
+
+ ret = devm_gpiochip_add_data(dev, &gpio->chip, gpio);
+ if (ret)
+ return dev_err_probe(dev, ret, "gpiochip_add error\n");
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(devm_tng_gpio_probe, GPIO_TANGIER);
+
+int tng_gpio_suspend(struct device *dev)
+{
+ struct tng_gpio *priv = dev_get_drvdata(dev);
+ struct tng_gpio_context *ctx = priv->ctx;
+ unsigned long flags;
+ unsigned int base;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) {
+ /* GPLR is RO, values read will be restored using GPSR */
+ ctx->level = readl(gpio_reg(&priv->chip, base, GPLR));
+
+ ctx->gpdr = readl(gpio_reg(&priv->chip, base, GPDR));
+ ctx->grer = readl(gpio_reg(&priv->chip, base, GRER));
+ ctx->gfer = readl(gpio_reg(&priv->chip, base, GFER));
+ ctx->gimr = readl(gpio_reg(&priv->chip, base, GIMR));
+
+ ctx->gwmr = readl(gpio_reg(&priv->chip, base, priv->wake_regs.gwmr));
+ }
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(tng_gpio_suspend, GPIO_TANGIER);
+
+int tng_gpio_resume(struct device *dev)
+{
+ struct tng_gpio *priv = dev_get_drvdata(dev);
+ struct tng_gpio_context *ctx = priv->ctx;
+ unsigned long flags;
+ unsigned int base;
+
+ raw_spin_lock_irqsave(&priv->lock, flags);
+
+ for (base = 0; base < priv->chip.ngpio; base += 32, ctx++) {
+ /* GPLR is RO, values read will be restored using GPSR */
+ writel(ctx->level, gpio_reg(&priv->chip, base, GPSR));
+
+ writel(ctx->gpdr, gpio_reg(&priv->chip, base, GPDR));
+ writel(ctx->grer, gpio_reg(&priv->chip, base, GRER));
+ writel(ctx->gfer, gpio_reg(&priv->chip, base, GFER));
+ writel(ctx->gimr, gpio_reg(&priv->chip, base, GIMR));
+
+ writel(ctx->gwmr, gpio_reg(&priv->chip, base, priv->wake_regs.gwmr));
+ }
+
+ raw_spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+EXPORT_SYMBOL_NS_GPL(tng_gpio_resume, GPIO_TANGIER);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_AUTHOR("Pandith N <pandith.n@intel.com>");
+MODULE_AUTHOR("Raag Jadav <raag.jadav@intel.com>");
+MODULE_DESCRIPTION("Intel Tangier GPIO driver");
+MODULE_LICENSE("GPL");
generated by cgit (git 2.34.1) at 2024-05-28 19:46:02 +0000