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path: root/drivers/pinctrl/pinctrl-apple-gpio.c
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-rw-r--r--drivers/pinctrl/pinctrl-apple-gpio.c531
1 files changed, 531 insertions, 0 deletions
diff --git a/drivers/pinctrl/pinctrl-apple-gpio.c b/drivers/pinctrl/pinctrl-apple-gpio.c
new file mode 100644
index 0000000000..3751c7de37
--- /dev/null
+++ b/drivers/pinctrl/pinctrl-apple-gpio.c
@@ -0,0 +1,531 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Apple SoC pinctrl+GPIO+external IRQ driver
+ *
+ * Copyright (C) The Asahi Linux Contributors
+ * Copyright (C) 2020 Corellium LLC
+ *
+ * Based on: pinctrl-pistachio.c
+ * Copyright (C) 2014 Imagination Technologies Ltd.
+ * Copyright (C) 2014 Google, Inc.
+ */
+
+#include <dt-bindings/pinctrl/apple.h>
+
+#include <linux/bitfield.h>
+#include <linux/bits.h>
+#include <linux/gpio/driver.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <linux/pinctrl/pinctrl.h>
+#include <linux/pinctrl/pinmux.h>
+
+#include "pinctrl-utils.h"
+#include "core.h"
+#include "pinmux.h"
+
+struct apple_gpio_pinctrl {
+ struct device *dev;
+ struct pinctrl_dev *pctldev;
+
+ void __iomem *base;
+ struct regmap *map;
+
+ struct pinctrl_desc pinctrl_desc;
+ struct gpio_chip gpio_chip;
+ u8 irqgrps[];
+};
+
+#define REG_GPIO(x) (4 * (x))
+#define REG_GPIOx_DATA BIT(0)
+#define REG_GPIOx_MODE GENMASK(3, 1)
+#define REG_GPIOx_OUT 1
+#define REG_GPIOx_IN_IRQ_HI 2
+#define REG_GPIOx_IN_IRQ_LO 3
+#define REG_GPIOx_IN_IRQ_UP 4
+#define REG_GPIOx_IN_IRQ_DN 5
+#define REG_GPIOx_IN_IRQ_ANY 6
+#define REG_GPIOx_IN_IRQ_OFF 7
+#define REG_GPIOx_PERIPH GENMASK(6, 5)
+#define REG_GPIOx_PULL GENMASK(8, 7)
+#define REG_GPIOx_PULL_OFF 0
+#define REG_GPIOx_PULL_DOWN 1
+#define REG_GPIOx_PULL_UP_STRONG 2
+#define REG_GPIOx_PULL_UP 3
+#define REG_GPIOx_INPUT_ENABLE BIT(9)
+#define REG_GPIOx_DRIVE_STRENGTH0 GENMASK(11, 10)
+#define REG_GPIOx_SCHMITT BIT(15)
+#define REG_GPIOx_GRP GENMASK(18, 16)
+#define REG_GPIOx_LOCK BIT(21)
+#define REG_GPIOx_DRIVE_STRENGTH1 GENMASK(23, 22)
+#define REG_IRQ(g, x) (0x800 + 0x40 * (g) + 4 * ((x) >> 5))
+
+struct regmap_config regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
+ .cache_type = REGCACHE_FLAT,
+ .max_register = 512 * sizeof(u32),
+ .num_reg_defaults_raw = 512,
+ .use_relaxed_mmio = true,
+ .use_raw_spinlock = true,
+};
+
+/* No locking needed to mask/unmask IRQs as the interrupt mode is per pin-register. */
+static void apple_gpio_set_reg(struct apple_gpio_pinctrl *pctl,
+ unsigned int pin, u32 mask, u32 value)
+{
+ regmap_update_bits(pctl->map, REG_GPIO(pin), mask, value);
+}
+
+static u32 apple_gpio_get_reg(struct apple_gpio_pinctrl *pctl,
+ unsigned int pin)
+{
+ int ret;
+ u32 val;
+
+ ret = regmap_read(pctl->map, REG_GPIO(pin), &val);
+ if (ret)
+ return 0;
+
+ return val;
+}
+
+/* Pin controller functions */
+
+static int apple_gpio_dt_node_to_map(struct pinctrl_dev *pctldev,
+ struct device_node *node,
+ struct pinctrl_map **map,
+ unsigned *num_maps)
+{
+ unsigned reserved_maps;
+ struct apple_gpio_pinctrl *pctl;
+ u32 pinfunc, pin, func;
+ int num_pins, i, ret;
+ const char *group_name;
+ const char *function_name;
+
+ *map = NULL;
+ *num_maps = 0;
+ reserved_maps = 0;
+
+ pctl = pinctrl_dev_get_drvdata(pctldev);
+
+ ret = of_property_count_u32_elems(node, "pinmux");
+ if (ret <= 0) {
+ dev_err(pctl->dev,
+ "missing or empty pinmux property in node %pOFn.\n",
+ node);
+ return ret ? ret : -EINVAL;
+ }
+
+ num_pins = ret;
+
+ ret = pinctrl_utils_reserve_map(pctldev, map, &reserved_maps, num_maps, num_pins);
+ if (ret)
+ return ret;
+
+ for (i = 0; i < num_pins; i++) {
+ ret = of_property_read_u32_index(node, "pinmux", i, &pinfunc);
+ if (ret)
+ goto free_map;
+
+ pin = APPLE_PIN(pinfunc);
+ func = APPLE_FUNC(pinfunc);
+
+ if (func >= pinmux_generic_get_function_count(pctldev)) {
+ ret = -EINVAL;
+ goto free_map;
+ }
+
+ group_name = pinctrl_generic_get_group_name(pctldev, pin);
+ function_name = pinmux_generic_get_function_name(pctl->pctldev, func);
+ ret = pinctrl_utils_add_map_mux(pctl->pctldev, map,
+ &reserved_maps, num_maps,
+ group_name, function_name);
+ if (ret)
+ goto free_map;
+ }
+
+free_map:
+ if (ret < 0)
+ pinctrl_utils_free_map(pctldev, *map, *num_maps);
+
+ return ret;
+}
+
+static const struct pinctrl_ops apple_gpio_pinctrl_ops = {
+ .get_groups_count = pinctrl_generic_get_group_count,
+ .get_group_name = pinctrl_generic_get_group_name,
+ .get_group_pins = pinctrl_generic_get_group_pins,
+ .dt_node_to_map = apple_gpio_dt_node_to_map,
+ .dt_free_map = pinctrl_utils_free_map,
+};
+
+/* Pin multiplexer functions */
+
+static int apple_gpio_pinmux_set(struct pinctrl_dev *pctldev, unsigned func,
+ unsigned group)
+{
+ struct apple_gpio_pinctrl *pctl = pinctrl_dev_get_drvdata(pctldev);
+
+ apple_gpio_set_reg(
+ pctl, group, REG_GPIOx_PERIPH | REG_GPIOx_INPUT_ENABLE,
+ FIELD_PREP(REG_GPIOx_PERIPH, func) | REG_GPIOx_INPUT_ENABLE);
+
+ return 0;
+}
+
+static const struct pinmux_ops apple_gpio_pinmux_ops = {
+ .get_functions_count = pinmux_generic_get_function_count,
+ .get_function_name = pinmux_generic_get_function_name,
+ .get_function_groups = pinmux_generic_get_function_groups,
+ .set_mux = apple_gpio_pinmux_set,
+ .strict = true,
+};
+
+/* GPIO chip functions */
+
+static int apple_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
+ unsigned int reg = apple_gpio_get_reg(pctl, offset);
+
+ if (FIELD_GET(REG_GPIOx_MODE, reg) == REG_GPIOx_OUT)
+ return GPIO_LINE_DIRECTION_OUT;
+ return GPIO_LINE_DIRECTION_IN;
+}
+
+static int apple_gpio_get(struct gpio_chip *chip, unsigned offset)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
+ unsigned int reg = apple_gpio_get_reg(pctl, offset);
+
+ /*
+ * If this is an input GPIO, read the actual value (not the
+ * cached regmap value)
+ */
+ if (FIELD_GET(REG_GPIOx_MODE, reg) != REG_GPIOx_OUT)
+ reg = readl_relaxed(pctl->base + REG_GPIO(offset));
+
+ return !!(reg & REG_GPIOx_DATA);
+}
+
+static void apple_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
+
+ apple_gpio_set_reg(pctl, offset, REG_GPIOx_DATA, value ? REG_GPIOx_DATA : 0);
+}
+
+static int apple_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
+
+ apple_gpio_set_reg(pctl, offset,
+ REG_GPIOx_PERIPH | REG_GPIOx_MODE | REG_GPIOx_DATA |
+ REG_GPIOx_INPUT_ENABLE,
+ FIELD_PREP(REG_GPIOx_MODE, REG_GPIOx_IN_IRQ_OFF) |
+ REG_GPIOx_INPUT_ENABLE);
+ return 0;
+}
+
+static int apple_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset, int value)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
+
+ apple_gpio_set_reg(pctl, offset,
+ REG_GPIOx_PERIPH | REG_GPIOx_MODE | REG_GPIOx_DATA,
+ FIELD_PREP(REG_GPIOx_MODE, REG_GPIOx_OUT) |
+ (value ? REG_GPIOx_DATA : 0));
+ return 0;
+}
+
+/* IRQ chip functions */
+
+static void apple_gpio_irq_ack(struct irq_data *data)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(irq_data_get_irq_chip_data(data));
+ unsigned int irqgrp = FIELD_GET(REG_GPIOx_GRP, apple_gpio_get_reg(pctl, data->hwirq));
+
+ writel(BIT(data->hwirq % 32), pctl->base + REG_IRQ(irqgrp, data->hwirq));
+}
+
+static unsigned int apple_gpio_irq_type(unsigned int type)
+{
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_RISING:
+ return REG_GPIOx_IN_IRQ_UP;
+ case IRQ_TYPE_EDGE_FALLING:
+ return REG_GPIOx_IN_IRQ_DN;
+ case IRQ_TYPE_EDGE_BOTH:
+ return REG_GPIOx_IN_IRQ_ANY;
+ case IRQ_TYPE_LEVEL_HIGH:
+ return REG_GPIOx_IN_IRQ_HI;
+ case IRQ_TYPE_LEVEL_LOW:
+ return REG_GPIOx_IN_IRQ_LO;
+ default:
+ return REG_GPIOx_IN_IRQ_OFF;
+ }
+}
+
+static void apple_gpio_irq_mask(struct irq_data *data)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(gc);
+
+ apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
+ FIELD_PREP(REG_GPIOx_MODE, REG_GPIOx_IN_IRQ_OFF));
+ gpiochip_disable_irq(gc, data->hwirq);
+}
+
+static void apple_gpio_irq_unmask(struct irq_data *data)
+{
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(data);
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(gc);
+ unsigned int irqtype = apple_gpio_irq_type(irqd_get_trigger_type(data));
+
+ gpiochip_enable_irq(gc, data->hwirq);
+ apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
+ FIELD_PREP(REG_GPIOx_MODE, irqtype));
+}
+
+static unsigned int apple_gpio_irq_startup(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(chip);
+
+ apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_GRP,
+ FIELD_PREP(REG_GPIOx_GRP, 0));
+
+ apple_gpio_direction_input(chip, data->hwirq);
+ apple_gpio_irq_unmask(data);
+
+ return 0;
+}
+
+static int apple_gpio_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ struct apple_gpio_pinctrl *pctl = gpiochip_get_data(irq_data_get_irq_chip_data(data));
+ unsigned int irqtype = apple_gpio_irq_type(type);
+
+ if (irqtype == REG_GPIOx_IN_IRQ_OFF)
+ return -EINVAL;
+
+ apple_gpio_set_reg(pctl, data->hwirq, REG_GPIOx_MODE,
+ FIELD_PREP(REG_GPIOx_MODE, irqtype));
+
+ if (type & IRQ_TYPE_LEVEL_MASK)
+ irq_set_handler_locked(data, handle_level_irq);
+ else
+ irq_set_handler_locked(data, handle_edge_irq);
+ return 0;
+}
+
+static void apple_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u8 *grpp = irq_desc_get_handler_data(desc);
+ struct apple_gpio_pinctrl *pctl;
+ unsigned int pinh, pinl;
+ unsigned long pending;
+ struct gpio_chip *gc;
+
+ pctl = container_of(grpp - *grpp, typeof(*pctl), irqgrps[0]);
+ gc = &pctl->gpio_chip;
+
+ chained_irq_enter(chip, desc);
+ for (pinh = 0; pinh < gc->ngpio; pinh += 32) {
+ pending = readl_relaxed(pctl->base + REG_IRQ(*grpp, pinh));
+ for_each_set_bit(pinl, &pending, 32)
+ generic_handle_domain_irq(gc->irq.domain, pinh + pinl);
+ }
+ chained_irq_exit(chip, desc);
+}
+
+static const struct irq_chip apple_gpio_irqchip = {
+ .name = "Apple-GPIO",
+ .irq_startup = apple_gpio_irq_startup,
+ .irq_ack = apple_gpio_irq_ack,
+ .irq_mask = apple_gpio_irq_mask,
+ .irq_unmask = apple_gpio_irq_unmask,
+ .irq_set_type = apple_gpio_irq_set_type,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
+/* Probe & register */
+
+static int apple_gpio_register(struct apple_gpio_pinctrl *pctl)
+{
+ struct gpio_irq_chip *girq = &pctl->gpio_chip.irq;
+ void **irq_data = NULL;
+ int ret;
+
+ pctl->gpio_chip.label = dev_name(pctl->dev);
+ pctl->gpio_chip.request = gpiochip_generic_request;
+ pctl->gpio_chip.free = gpiochip_generic_free;
+ pctl->gpio_chip.get_direction = apple_gpio_get_direction;
+ pctl->gpio_chip.direction_input = apple_gpio_direction_input;
+ pctl->gpio_chip.direction_output = apple_gpio_direction_output;
+ pctl->gpio_chip.get = apple_gpio_get;
+ pctl->gpio_chip.set = apple_gpio_set;
+ pctl->gpio_chip.base = -1;
+ pctl->gpio_chip.ngpio = pctl->pinctrl_desc.npins;
+ pctl->gpio_chip.parent = pctl->dev;
+
+ if (girq->num_parents) {
+ int i;
+
+ gpio_irq_chip_set_chip(girq, &apple_gpio_irqchip);
+ girq->parent_handler = apple_gpio_irq_handler;
+
+ girq->parents = kmalloc_array(girq->num_parents,
+ sizeof(*girq->parents),
+ GFP_KERNEL);
+ irq_data = kmalloc_array(girq->num_parents, sizeof(*irq_data),
+ GFP_KERNEL);
+ if (!girq->parents || !irq_data) {
+ ret = -ENOMEM;
+ goto out_free_irq_data;
+ }
+
+ for (i = 0; i < girq->num_parents; i++) {
+ ret = platform_get_irq(to_platform_device(pctl->dev), i);
+ if (ret < 0)
+ goto out_free_irq_data;
+
+ girq->parents[i] = ret;
+ pctl->irqgrps[i] = i;
+ irq_data[i] = &pctl->irqgrps[i];
+ }
+
+ girq->parent_handler_data_array = irq_data;
+ girq->per_parent_data = true;
+ girq->default_type = IRQ_TYPE_NONE;
+ girq->handler = handle_level_irq;
+ }
+
+ ret = devm_gpiochip_add_data(pctl->dev, &pctl->gpio_chip, pctl);
+
+out_free_irq_data:
+ kfree(girq->parents);
+ kfree(irq_data);
+
+ return ret;
+}
+
+static int apple_gpio_pinctrl_probe(struct platform_device *pdev)
+{
+ struct apple_gpio_pinctrl *pctl;
+ struct pinctrl_pin_desc *pins;
+ unsigned int npins;
+ const char **pin_names;
+ unsigned int *pin_nums;
+ static const char* pinmux_functions[] = {
+ "gpio", "periph1", "periph2", "periph3"
+ };
+ unsigned int i, nirqs = 0;
+ int res;
+
+ if (of_property_read_bool(pdev->dev.of_node, "interrupt-controller")) {
+ res = platform_irq_count(pdev);
+ if (res > 0)
+ nirqs = res;
+ }
+
+ pctl = devm_kzalloc(&pdev->dev, struct_size(pctl, irqgrps, nirqs),
+ GFP_KERNEL);
+ if (!pctl)
+ return -ENOMEM;
+ pctl->dev = &pdev->dev;
+ pctl->gpio_chip.irq.num_parents = nirqs;
+ dev_set_drvdata(&pdev->dev, pctl);
+
+ if (of_property_read_u32(pdev->dev.of_node, "apple,npins", &npins))
+ return dev_err_probe(&pdev->dev, -EINVAL,
+ "apple,npins property not found\n");
+
+ pins = devm_kmalloc_array(&pdev->dev, npins, sizeof(pins[0]),
+ GFP_KERNEL);
+ pin_names = devm_kmalloc_array(&pdev->dev, npins, sizeof(pin_names[0]),
+ GFP_KERNEL);
+ pin_nums = devm_kmalloc_array(&pdev->dev, npins, sizeof(pin_nums[0]),
+ GFP_KERNEL);
+ if (!pins || !pin_names || !pin_nums)
+ return -ENOMEM;
+
+ pctl->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(pctl->base))
+ return PTR_ERR(pctl->base);
+
+ pctl->map = devm_regmap_init_mmio(&pdev->dev, pctl->base, &regmap_config);
+ if (IS_ERR(pctl->map))
+ return dev_err_probe(&pdev->dev, PTR_ERR(pctl->map),
+ "Failed to create regmap\n");
+
+ for (i = 0; i < npins; i++) {
+ pins[i].number = i;
+ pins[i].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "PIN%u", i);
+ pins[i].drv_data = pctl;
+ pin_names[i] = pins[i].name;
+ pin_nums[i] = i;
+ }
+
+ pctl->pinctrl_desc.name = dev_name(pctl->dev);
+ pctl->pinctrl_desc.pins = pins;
+ pctl->pinctrl_desc.npins = npins;
+ pctl->pinctrl_desc.pctlops = &apple_gpio_pinctrl_ops;
+ pctl->pinctrl_desc.pmxops = &apple_gpio_pinmux_ops;
+
+ pctl->pctldev = devm_pinctrl_register(&pdev->dev, &pctl->pinctrl_desc, pctl);
+ if (IS_ERR(pctl->pctldev))
+ return dev_err_probe(&pdev->dev, PTR_ERR(pctl->pctldev),
+ "Failed to register pinctrl device.\n");
+
+ for (i = 0; i < npins; i++) {
+ res = pinctrl_generic_add_group(pctl->pctldev, pins[i].name,
+ pin_nums + i, 1, pctl);
+ if (res < 0)
+ return dev_err_probe(pctl->dev, res,
+ "Failed to register group");
+ }
+
+ for (i = 0; i < ARRAY_SIZE(pinmux_functions); ++i) {
+ res = pinmux_generic_add_function(pctl->pctldev, pinmux_functions[i],
+ pin_names, npins, pctl);
+ if (res < 0)
+ return dev_err_probe(pctl->dev, res,
+ "Failed to register function.");
+ }
+
+ return apple_gpio_register(pctl);
+}
+
+static const struct of_device_id apple_gpio_pinctrl_of_match[] = {
+ { .compatible = "apple,pinctrl", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, apple_gpio_pinctrl_of_match);
+
+static struct platform_driver apple_gpio_pinctrl_driver = {
+ .driver = {
+ .name = "apple-gpio-pinctrl",
+ .of_match_table = apple_gpio_pinctrl_of_match,
+ .suppress_bind_attrs = true,
+ },
+ .probe = apple_gpio_pinctrl_probe,
+};
+module_platform_driver(apple_gpio_pinctrl_driver);
+
+MODULE_DESCRIPTION("Apple pinctrl/GPIO driver");
+MODULE_AUTHOR("Stan Skowronek <stan@corellium.com>");
+MODULE_AUTHOR("Joey Gouly <joey.gouly@arm.com>");
+MODULE_LICENSE("GPL v2");