@@ -13429,6 +13429,11 @@ F: drivers/nubus/
F: include/linux/nubus.h
F: include/uapi/linux/nubus.h
+NUVOTON M058SSAN GPIO DRIVER
+M: Filippo Copetti <filippo.copetti@eurotech.com>
+S: Maintained
+F: drivers/gpio/gpio-m058ssan.c
+
NVIDIA (rivafb and nvidiafb) FRAMEBUFFER DRIVER
M: Antonino Daplas <adaplas@gmail.com>
L: linux-fbdev@vger.kernel.org
@@ -1030,6 +1030,12 @@ config GPIO_MAX732X_IRQ
Say yes here to enable the max732x to be used as an interrupt
controller. It requires the driver to be built in the kernel.
+config GPIO_M058SSAN
+ tristate "M085 8-DI 8-DO I2C expander"
+ depends on UBUNTU_ODM_DRIVERS
+ help
+ Say yes here to enable the M058SSAN gpio driver.
+
config GPIO_PCA953X
tristate "PCA95[357]x, PCA9698, TCA64xx, and MAX7310 I/O ports"
select REGMAP_I2C
@@ -84,6 +84,7 @@ obj-$(CONFIG_GPIO_LP873X) += gpio-lp873x.o
obj-$(CONFIG_GPIO_LP87565) += gpio-lp87565.o
obj-$(CONFIG_GPIO_LPC18XX) += gpio-lpc18xx.o
obj-$(CONFIG_GPIO_LPC32XX) += gpio-lpc32xx.o
+obj-$(CONFIG_GPIO_M058SSAN) += gpio-m058ssan.o
obj-$(CONFIG_GPIO_MADERA) += gpio-madera.o
obj-$(CONFIG_GPIO_MAX3191X) += gpio-max3191x.o
obj-$(CONFIG_GPIO_MAX7300) += gpio-max7300.o
new file mode 100644
@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for M058SSAN I2C GPO expander
+ *
+ * Copyright (C) 2023 Filippo Copetti <filippo.copetti@eurotech.com>
+ *
+ * Based on gpio-tpic2810.c
+ * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
+ * Andrew F. Davis <afd@ti.com>
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/property.h>
+
+/*
+ * GPIO bank #1 (offset 0...7) is configured as output
+ * GPIO bank #2 (offset 8...15) is configured as input
+ */
+
+#define M058SSAN_OUTPUT_BANK 0x01
+#define M058SSAN_INPUT_BANK 0x02
+#define M058SSAN_INPUT_OUTPUT_OFFSET 0x07
+
+/**
+ * m058ssan_read(gpio, &gpio->out, 0x02);
+ * o->out * struct m058ssan - GPIO driver data
+ * @chip: GPIO controller chip
+ * @lock: Protects write sequences
+ * @out: Buffer for device register
+ */
+struct m058ssan {
+ struct gpio_chip chip;
+ struct mutex lock;
+ u8 out;
+};
+
+static int m058ssan_read(struct m058ssan *gpio, u8 *value, u8 address)
+{
+ struct i2c_client *client = to_i2c_client(gpio->chip.parent);
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(client, address);
+
+ if (ret < 0)
+ return ret;
+
+ *value = ret;
+
+ return 0;
+}
+
+static int m058ssan_write(struct m058ssan *gpio, u8 value, u8 address)
+{
+ struct i2c_client *client = to_i2c_client(gpio->chip.parent);
+
+ return i2c_smbus_write_byte_data(client, address, value);
+}
+
+static int m058ssan_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+ if (offset > M058SSAN_INPUT_OUTPUT_OFFSET)
+ return GPIO_LINE_DIRECTION_IN;
+ else
+ return GPIO_LINE_DIRECTION_OUT;
+}
+
+static int m058ssan_gpio_direction_input(struct gpio_chip *gc, unsigned int offset)
+{
+ if (offset > M058SSAN_INPUT_OUTPUT_OFFSET)
+ return 0;
+ else
+ return -1;
+}
+
+static int m058ssan_gpio_direction_output(struct gpio_chip *gc, unsigned int offset, int value)
+{
+ if (offset > M058SSAN_INPUT_OUTPUT_OFFSET)
+ return -1;
+ else
+ return 0;
+}
+
+static int m058ssan_get(struct gpio_chip *chip, unsigned int offset)
+{
+ struct m058ssan *gpio = gpiochip_get_data(chip);
+ u8 buffer;
+ int ret;
+
+ if (offset > M058SSAN_INPUT_OUTPUT_OFFSET) {
+ ret = m058ssan_read(gpio, &buffer, M058SSAN_INPUT_BANK);
+ offset -= (M058SSAN_INPUT_OUTPUT_OFFSET + 1);
+ } else {
+ ret = m058ssan_read(gpio, &buffer, M058SSAN_OUTPUT_BANK);
+ }
+ if (ret)
+ return ret;
+
+ return buffer & BIT(offset);
+}
+
+static void m058ssan_set(struct gpio_chip *chip, unsigned int offset, int value)
+{
+ struct m058ssan *gpio = gpiochip_get_data(chip);
+ u8 buffer;
+ int ret;
+
+ if (offset > M058SSAN_INPUT_OUTPUT_OFFSET)
+ return;
+
+ mutex_lock(&gpio->lock);
+
+ buffer = gpio->out;
+
+ if (value)
+ buffer |= BIT(offset);
+ else
+ buffer &= ~BIT(offset);
+
+ ret = m058ssan_write(gpio, buffer, M058SSAN_OUTPUT_BANK);
+
+ if (ret)
+ goto out;
+
+ gpio->out = buffer;
+
+out:
+ mutex_unlock(&gpio->lock);
+}
+
+static int m058ssan_probe(struct i2c_client *client)
+{
+ struct m058ssan *gpio;
+
+ gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
+
+ if (!gpio)
+ return -ENOMEM;
+
+ gpio->chip.label = client->name;
+ gpio->chip.parent = &client->dev;
+ gpio->chip.owner = THIS_MODULE;
+ gpio->chip.get_direction = m058ssan_get_direction;
+ gpio->chip.direction_input = m058ssan_gpio_direction_input;
+ gpio->chip.direction_output = m058ssan_gpio_direction_output;
+ gpio->chip.get = m058ssan_get;
+ gpio->chip.set = m058ssan_set;
+ gpio->chip.base = -1;
+ gpio->chip.ngpio = 16;
+ gpio->chip.can_sleep = true;
+
+ mutex_init(&gpio->lock);
+
+ /* Read the current output level */
+ if (gpio->out > M058SSAN_INPUT_OUTPUT_OFFSET)
+ m058ssan_read(gpio, &gpio->out, M058SSAN_INPUT_BANK);
+ else
+ m058ssan_read(gpio, &gpio->out, M058SSAN_OUTPUT_BANK);
+
+ return devm_gpiochip_add_data(&client->dev, &gpio->chip, gpio);
+}
+
+static const struct i2c_device_id m058ssan_id_table[] = {
+ {"m058ssan", 4},
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(i2c, m058ssan_id_table);
+
+static const struct of_device_id m058ssan_of_match_table[] = {
+ {.compatible = "nuvoton,m058ssan", .data = (void *)4},
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, m058ssan_of_match_table);
+
+static struct i2c_driver m058ssan_driver = {
+ .driver = {
+ .name = "m058ssan",
+ .of_match_table = m058ssan_of_match_table,
+ },
+ .probe_new = m058ssan_probe,
+ .id_table = m058ssan_id_table,
+};
+
+module_i2c_driver(m058ssan_driver);
+
+MODULE_AUTHOR("Filippo Copetti <filippo.copetti@eurotech.com>");
+MODULE_DESCRIPTION("GPIO expander driver for M058SSAN");
+MODULE_LICENSE("GPL v2");