1 files changed, 460 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-msc313.c b/drivers/gpio/gpio-msc313.c
new file mode 100644
index 000000000000..da31a5ff7a2b
--- /dev/null
+++ b/drivers/gpio/gpio-msc313.c
@@ -0,0 +1,460 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (C) 2020 Daniel Palmer<daniel@thingy.jp> */
+
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/gpio/driver.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include <dt-bindings/gpio/msc313-gpio.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+#define DRIVER_NAME "gpio-msc313"
+
+#define MSC313_GPIO_IN  BIT(0)
+#define MSC313_GPIO_OUT BIT(4)
+#define MSC313_GPIO_OEN BIT(5)
+
+/*
+ * These bits need to be saved to correctly restore the
+ * gpio state when resuming from suspend to memory.
+ */
+#define MSC313_GPIO_BITSTOSAVE (MSC313_GPIO_OUT | MSC313_GPIO_OEN)
+
+/* pad names for fuart, same for all SoCs so far */
+#define MSC313_PINNAME_FUART_RX		"fuart_rx"
+#define MSC313_PINNAME_FUART_TX		"fuart_tx"
+#define MSC313_PINNAME_FUART_CTS	"fuart_cts"
+#define MSC313_PINNAME_FUART_RTS	"fuart_rts"
+
+/* pad names for sr, mercury5 is different */
+#define MSC313_PINNAME_SR_IO2		"sr_io2"
+#define MSC313_PINNAME_SR_IO3		"sr_io3"
+#define MSC313_PINNAME_SR_IO4		"sr_io4"
+#define MSC313_PINNAME_SR_IO5		"sr_io5"
+#define MSC313_PINNAME_SR_IO6		"sr_io6"
+#define MSC313_PINNAME_SR_IO7		"sr_io7"
+#define MSC313_PINNAME_SR_IO8		"sr_io8"
+#define MSC313_PINNAME_SR_IO9		"sr_io9"
+#define MSC313_PINNAME_SR_IO10		"sr_io10"
+#define MSC313_PINNAME_SR_IO11		"sr_io11"
+#define MSC313_PINNAME_SR_IO12		"sr_io12"
+#define MSC313_PINNAME_SR_IO13		"sr_io13"
+#define MSC313_PINNAME_SR_IO14		"sr_io14"
+#define MSC313_PINNAME_SR_IO15		"sr_io15"
+#define MSC313_PINNAME_SR_IO16		"sr_io16"
+#define MSC313_PINNAME_SR_IO17		"sr_io17"
+
+/* pad names for sd, same for all SoCs so far */
+#define MSC313_PINNAME_SD_CLK		"sd_clk"
+#define MSC313_PINNAME_SD_CMD		"sd_cmd"
+#define MSC313_PINNAME_SD_D0		"sd_d0"
+#define MSC313_PINNAME_SD_D1		"sd_d1"
+#define MSC313_PINNAME_SD_D2		"sd_d2"
+#define MSC313_PINNAME_SD_D3		"sd_d3"
+
+/* pad names for i2c1, same for all SoCs so for */
+#define MSC313_PINNAME_I2C1_SCL		"i2c1_scl"
+#define MSC313_PINNAME_I2C1_SCA		"i2c1_sda"
+
+/* pad names for spi0, same for all SoCs so far */
+#define MSC313_PINNAME_SPI0_CZ		"spi0_cz"
+#define MSC313_PINNAME_SPI0_CK		"spi0_ck"
+#define MSC313_PINNAME_SPI0_DI		"spi0_di"
+#define MSC313_PINNAME_SPI0_DO		"spi0_do"
+
+#define FUART_NAMES			\
+	MSC313_PINNAME_FUART_RX,	\
+	MSC313_PINNAME_FUART_TX,	\
+	MSC313_PINNAME_FUART_CTS,	\
+	MSC313_PINNAME_FUART_RTS
+
+#define OFF_FUART_RX	0x50
+#define OFF_FUART_TX	0x54
+#define OFF_FUART_CTS	0x58
+#define OFF_FUART_RTS	0x5c
+
+#define FUART_OFFSETS	\
+	OFF_FUART_RX,	\
+	OFF_FUART_TX,	\
+	OFF_FUART_CTS,	\
+	OFF_FUART_RTS
+
+#define SR_NAMES		\
+	MSC313_PINNAME_SR_IO2,	\
+	MSC313_PINNAME_SR_IO3,	\
+	MSC313_PINNAME_SR_IO4,	\
+	MSC313_PINNAME_SR_IO5,	\
+	MSC313_PINNAME_SR_IO6,	\
+	MSC313_PINNAME_SR_IO7,	\
+	MSC313_PINNAME_SR_IO8,	\
+	MSC313_PINNAME_SR_IO9,	\
+	MSC313_PINNAME_SR_IO10,	\
+	MSC313_PINNAME_SR_IO11,	\
+	MSC313_PINNAME_SR_IO12,	\
+	MSC313_PINNAME_SR_IO13,	\
+	MSC313_PINNAME_SR_IO14,	\
+	MSC313_PINNAME_SR_IO15,	\
+	MSC313_PINNAME_SR_IO16,	\
+	MSC313_PINNAME_SR_IO17
+
+#define OFF_SR_IO2	0x88
+#define OFF_SR_IO3	0x8c
+#define OFF_SR_IO4	0x90
+#define OFF_SR_IO5	0x94
+#define OFF_SR_IO6	0x98
+#define OFF_SR_IO7	0x9c
+#define OFF_SR_IO8	0xa0
+#define OFF_SR_IO9	0xa4
+#define OFF_SR_IO10	0xa8
+#define OFF_SR_IO11	0xac
+#define OFF_SR_IO12	0xb0
+#define OFF_SR_IO13	0xb4
+#define OFF_SR_IO14	0xb8
+#define OFF_SR_IO15	0xbc
+#define OFF_SR_IO16	0xc0
+#define OFF_SR_IO17	0xc4
+
+#define SR_OFFSETS	\
+	OFF_SR_IO2,	\
+	OFF_SR_IO3,	\
+	OFF_SR_IO4,	\
+	OFF_SR_IO5,	\
+	OFF_SR_IO6,	\
+	OFF_SR_IO7,	\
+	OFF_SR_IO8,	\
+	OFF_SR_IO9,	\
+	OFF_SR_IO10,	\
+	OFF_SR_IO11,	\
+	OFF_SR_IO12,	\
+	OFF_SR_IO13,	\
+	OFF_SR_IO14,	\
+	OFF_SR_IO15,	\
+	OFF_SR_IO16,	\
+	OFF_SR_IO17
+
+#define SD_NAMES		\
+	MSC313_PINNAME_SD_CLK,	\
+	MSC313_PINNAME_SD_CMD,	\
+	MSC313_PINNAME_SD_D0,	\
+	MSC313_PINNAME_SD_D1,	\
+	MSC313_PINNAME_SD_D2,	\
+	MSC313_PINNAME_SD_D3
+
+#define OFF_SD_CLK	0x140
+#define OFF_SD_CMD	0x144
+#define OFF_SD_D0	0x148
+#define OFF_SD_D1	0x14c
+#define OFF_SD_D2	0x150
+#define OFF_SD_D3	0x154
+
+#define SD_OFFSETS	\
+	OFF_SD_CLK,	\
+	OFF_SD_CMD,	\
+	OFF_SD_D0,	\
+	OFF_SD_D1,	\
+	OFF_SD_D2,	\
+	OFF_SD_D3
+
+#define I2C1_NAMES			\
+	MSC313_PINNAME_I2C1_SCL,	\
+	MSC313_PINNAME_I2C1_SCA
+
+#define OFF_I2C1_SCL	0x188
+#define OFF_I2C1_SCA	0x18c
+
+#define I2C1_OFFSETS	\
+	OFF_I2C1_SCL,	\
+	OFF_I2C1_SCA
+
+#define SPI0_NAMES		\
+	MSC313_PINNAME_SPI0_CZ,	\
+	MSC313_PINNAME_SPI0_CK,	\
+	MSC313_PINNAME_SPI0_DI,	\
+	MSC313_PINNAME_SPI0_DO
+
+#define OFF_SPI0_CZ	0x1c0
+#define OFF_SPI0_CK	0x1c4
+#define OFF_SPI0_DI	0x1c8
+#define OFF_SPI0_DO	0x1cc
+
+#define SPI0_OFFSETS	\
+	OFF_SPI0_CZ,	\
+	OFF_SPI0_CK,	\
+	OFF_SPI0_DI,	\
+	OFF_SPI0_DO
+
+struct msc313_gpio_data {
+	const char * const *names;
+	const unsigned int *offsets;
+	const unsigned int num;
+};
+
+#define MSC313_GPIO_CHIPDATA(_chip) \
+static const struct msc313_gpio_data _chip##_data = { \
+	.names = _chip##_names, \
+	.offsets = _chip##_offsets, \
+	.num = ARRAY_SIZE(_chip##_offsets), \
+}
+
+#ifdef CONFIG_MACH_INFINITY
+static const char * const msc313_names[] = {
+	FUART_NAMES,
+	SR_NAMES,
+	SD_NAMES,
+	I2C1_NAMES,
+	SPI0_NAMES,
+};
+
+static const unsigned int msc313_offsets[] = {
+	FUART_OFFSETS,
+	SR_OFFSETS,
+	SD_OFFSETS,
+	I2C1_OFFSETS,
+	SPI0_OFFSETS,
+};
+
+MSC313_GPIO_CHIPDATA(msc313);
+#endif
+
+struct msc313_gpio {
+	void __iomem *base;
+	const struct msc313_gpio_data *gpio_data;
+	u8 *saved;
+};
+
+static void msc313_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+	struct msc313_gpio *gpio = gpiochip_get_data(chip);
+	u8 gpioreg = readb_relaxed(gpio->base + gpio->gpio_data->offsets[offset]);
+
+	if (value)
+		gpioreg |= MSC313_GPIO_OUT;
+	else
+		gpioreg &= ~MSC313_GPIO_OUT;
+
+	writeb_relaxed(gpioreg, gpio->base + gpio->gpio_data->offsets[offset]);
+}
+
+static int msc313_gpio_get(struct gpio_chip *chip, unsigned int offset)
+{
+	struct msc313_gpio *gpio = gpiochip_get_data(chip);
+
+	return readb_relaxed(gpio->base + gpio->gpio_data->offsets[offset]) & MSC313_GPIO_IN;
+}
+
+static int msc313_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
+{
+	struct msc313_gpio *gpio = gpiochip_get_data(chip);
+	u8 gpioreg = readb_relaxed(gpio->base + gpio->gpio_data->offsets[offset]);
+
+	gpioreg |= MSC313_GPIO_OEN;
+	writeb_relaxed(gpioreg, gpio->base + gpio->gpio_data->offsets[offset]);
+
+	return 0;
+}
+
+static int msc313_gpio_direction_output(struct gpio_chip *chip, unsigned int offset, int value)
+{
+	struct msc313_gpio *gpio = gpiochip_get_data(chip);
+	u8 gpioreg = readb_relaxed(gpio->base + gpio->gpio_data->offsets[offset]);
+
+	gpioreg &= ~MSC313_GPIO_OEN;
+	if (value)
+		gpioreg |= MSC313_GPIO_OUT;
+	else
+		gpioreg &= ~MSC313_GPIO_OUT;
+	writeb_relaxed(gpioreg, gpio->base + gpio->gpio_data->offsets[offset]);
+
+	return 0;
+}
+
+/*
+ * The interrupt handling happens in the parent interrupt controller,
+ * we don't do anything here.
+ */
+static struct irq_chip msc313_gpio_irqchip = {
+	.name = "GPIO",
+	.irq_eoi = irq_chip_eoi_parent,
+	.irq_mask = irq_chip_mask_parent,
+	.irq_unmask = irq_chip_unmask_parent,
+	.irq_set_type = irq_chip_set_type_parent,
+	.irq_set_affinity = irq_chip_set_affinity_parent,
+};
+
+/*
+ * The parent interrupt controller needs the GIC interrupt type set to GIC_SPI
+ * so we need to provide the fwspec. Essentially gpiochip_populate_parent_fwspec_twocell
+ * that puts GIC_SPI into the first cell.
+ */
+static void *msc313_gpio_populate_parent_fwspec(struct gpio_chip *gc,
+					     unsigned int parent_hwirq,
+					     unsigned int parent_type)
+{
+	struct irq_fwspec *fwspec;
+
+	fwspec = kmalloc(sizeof(*fwspec), GFP_KERNEL);
+	if (!fwspec)
+		return NULL;
+
+	fwspec->fwnode = gc->irq.parent_domain->fwnode;
+	fwspec->param_count = 3;
+	fwspec->param[0] = GIC_SPI;
+	fwspec->param[1] = parent_hwirq;
+	fwspec->param[2] = parent_type;
+
+	return fwspec;
+}
+
+static int msc313e_gpio_child_to_parent_hwirq(struct gpio_chip *chip,
+					     unsigned int child,
+					     unsigned int child_type,
+					     unsigned int *parent,
+					     unsigned int *parent_type)
+{
+	struct msc313_gpio *priv = gpiochip_get_data(chip);
+	unsigned int offset = priv->gpio_data->offsets[child];
+
+	/*
+	 * only the spi0 pins have interrupts on the parent
+	 * on all of the known chips and so far they are all
+	 * mapped to the same place
+	 */
+	if (offset >= OFF_SPI0_CZ && offset <= OFF_SPI0_DO) {
+		*parent_type = child_type;
+		*parent = ((offset - OFF_SPI0_CZ) >> 2) + 28;
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static int msc313_gpio_probe(struct platform_device *pdev)
+{
+	const struct msc313_gpio_data *match_data;
+	struct msc313_gpio *gpio;
+	struct gpio_chip *gpiochip;
+	struct gpio_irq_chip *gpioirqchip;
+	struct irq_domain *parent_domain;
+	struct device_node *parent_node;
+	struct device *dev = &pdev->dev;
+	int ret;
+
+	match_data = of_device_get_match_data(dev);
+	if (!match_data)
+		return -EINVAL;
+
+	parent_node = of_irq_find_parent(dev->of_node);
+	if (!parent_node)
+		return -ENODEV;
+
+	parent_domain = irq_find_host(parent_node);
+	if (!parent_domain)
+		return -ENODEV;
+
+	gpio = devm_kzalloc(dev, sizeof(*gpio), GFP_KERNEL);
+	if (!gpio)
+		return -ENOMEM;
+
+	gpio->gpio_data = match_data;
+
+	gpio->saved = devm_kcalloc(dev, gpio->gpio_data->num, sizeof(*gpio->saved), GFP_KERNEL);
+	if (!gpio->saved)
+		return -ENOMEM;
+
+	gpio->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(gpio->base))
+		return PTR_ERR(gpio->base);
+
+	platform_set_drvdata(pdev, gpio);
+
+	gpiochip = devm_kzalloc(dev, sizeof(*gpiochip), GFP_KERNEL);
+	if (!gpiochip)
+		return -ENOMEM;
+
+	gpiochip->label = DRIVER_NAME;
+	gpiochip->parent = dev;
+	gpiochip->request = gpiochip_generic_request;
+	gpiochip->free = gpiochip_generic_free;
+	gpiochip->direction_input = msc313_gpio_direction_input;
+	gpiochip->direction_output = msc313_gpio_direction_output;
+	gpiochip->get = msc313_gpio_get;
+	gpiochip->set = msc313_gpio_set;
+	gpiochip->base = -1;
+	gpiochip->ngpio = gpio->gpio_data->num;
+	gpiochip->names = gpio->gpio_data->names;
+
+	gpioirqchip = &gpiochip->irq;
+	gpioirqchip->chip = &msc313_gpio_irqchip;
+	gpioirqchip->fwnode = of_node_to_fwnode(dev->of_node);
+	gpioirqchip->parent_domain = parent_domain;
+	gpioirqchip->child_to_parent_hwirq = msc313e_gpio_child_to_parent_hwirq;
+	gpioirqchip->populate_parent_alloc_arg = msc313_gpio_populate_parent_fwspec;
+	gpioirqchip->handler = handle_bad_irq;
+	gpioirqchip->default_type = IRQ_TYPE_NONE;
+
+	ret = devm_gpiochip_add_data(dev, gpiochip, gpio);
+	return ret;
+}
+
+static int msc313_gpio_remove(struct platform_device *pdev)
+{
+	return 0;
+}
+
+static const struct of_device_id msc313_gpio_of_match[] = {
+#ifdef CONFIG_MACH_INFINITY
+	{
+		.compatible = "mstar,msc313-gpio",
+		.data = &msc313_data,
+	},
+#endif
+	{ }
+};
+
+/*
+ * The GPIO controller loses the state of the registers when the
+ * SoC goes into suspend to memory mode so we need to save some
+ * of the register bits before suspending and put it back when resuming
+ */
+static int __maybe_unused msc313_gpio_suspend(struct device *dev)
+{
+	struct msc313_gpio *gpio = dev_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < gpio->gpio_data->num; i++)
+		gpio->saved[i] = readb_relaxed(gpio->base + gpio->gpio_data->offsets[i]) & MSC313_GPIO_BITSTOSAVE;
+
+	return 0;
+}
+
+static int __maybe_unused msc313_gpio_resume(struct device *dev)
+{
+	struct msc313_gpio *gpio = dev_get_drvdata(dev);
+	int i;
+
+	for (i = 0; i < gpio->gpio_data->num; i++)
+		writeb_relaxed(gpio->saved[i], gpio->base + gpio->gpio_data->offsets[i]);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(msc313_gpio_ops, msc313_gpio_suspend, msc313_gpio_resume);
+
+static struct platform_driver msc313_gpio_driver = {
+	.driver = {
+		.name = DRIVER_NAME,
+		.of_match_table = msc313_gpio_of_match,
+		.pm = &msc313_gpio_ops,
+	},
+	.probe = msc313_gpio_probe,
+	.remove = msc313_gpio_remove,
+};
+
+builtin_platform_driver(msc313_gpio_driver);