drivers/gpio: add support for MAX7320 i2c i/o expander
This commit adds support for the MAX7320 (and clones) gpio expander.
Signed-off-by: Hannes Schmelzer <hannes.schmelzer@br-automation.com>
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index f0439e2..40abc33 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -183,6 +183,14 @@
help
Support for the LPC32XX GPIO driver.
+config MAX7320_GPIO
+ bool "MAX7320 I2C GPIO Expander driver"
+ depends on DM_GPIO && DM_I2C
+ help
+ Support for MAX7320 I2C 8/16-bit GPIO expander.
+ original maxim device has 8 push/pull outputs,
+ some clones offers 16bit.
+
config MCP230XX_GPIO
bool "MCP230XX GPIO driver"
depends on DM
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index a9dc546..3c851b3 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -68,3 +68,4 @@
obj-$(CONFIG_NX_GPIO) += nx_gpio.o
obj-$(CONFIG_SIFIVE_GPIO) += sifive-gpio.o
obj-$(CONFIG_NOMADIK_GPIO) += nmk_gpio.o
+obj-$(CONFIG_MAX7320_GPIO) += max7320_gpio.o
diff --git a/drivers/gpio/max7320_gpio.c b/drivers/gpio/max7320_gpio.c
new file mode 100644
index 0000000..647aed9
--- /dev/null
+++ b/drivers/gpio/max7320_gpio.c
@@ -0,0 +1,113 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * max7320 I2C GPIO EXPANDER DRIVER
+ *
+ * Copyright (C) 2021 Hannes Schmelzer <oe5hpm@oevsv.at>
+ * B&R Industrial Automation GmbH - http://www.br-automation.com
+ *
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <i2c.h>
+#include <asm-generic/gpio.h>
+#include <linux/bitops.h>
+
+struct max7320_chip {
+ u32 outreg;
+};
+
+static int max7320_direction_output(struct udevice *dev,
+ unsigned int offset, int value)
+{
+ struct max7320_chip *plat = dev_get_plat(dev);
+ struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+ struct dm_i2c_chip *chip = dev_get_parent_plat(dev);
+
+ int ret;
+
+ if (value)
+ plat->outreg |= BIT(offset);
+ else
+ plat->outreg &= ~BIT(offset);
+
+ ret = dm_i2c_write(dev,
+ plat->outreg & 0xff,
+ (uint8_t *)&plat->outreg + 1,
+ uc_priv->gpio_count > 8 ? 1 : 0);
+ if (ret)
+ printf("%s i2c write failed to addr %x\n", __func__,
+ chip->chip_addr);
+
+ return ret;
+}
+
+static int max7320_get_value(struct udevice *dev, unsigned int offset)
+{
+ struct max7320_chip *plat = dev_get_plat(dev);
+
+ return (plat->outreg >> offset) & 0x1;
+}
+
+static int max7320_set_value(struct udevice *dev, unsigned int offset,
+ int value)
+{
+ return max7320_direction_output(dev, offset, value);
+}
+
+static int max7320_get_function(struct udevice *dev, unsigned int offset)
+{
+ return GPIOF_OUTPUT;
+}
+
+static int max7320_ofdata_plat(struct udevice *dev)
+{
+ struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ uc_priv->gpio_count = dev_read_u32_default(dev, "ngpios", 8);
+ if (uc_priv->gpio_count > 16) {
+ printf("%s: max7320 doesn't support more than 16 gpios!",
+ __func__);
+ return -EINVAL;
+ }
+
+ uc_priv->bank_name = fdt_getprop(gd->fdt_blob, dev_of_offset(dev),
+ "gpio-bank-name", NULL);
+ if (!uc_priv->bank_name)
+ uc_priv->bank_name = fdt_get_name(gd->fdt_blob,
+ dev_of_offset(dev), NULL);
+
+ return 0;
+}
+
+static int max7320_gpio_probe(struct udevice *dev)
+{
+ struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
+
+ debug("%s GPIO controller with %d gpios probed\n",
+ uc_priv->bank_name, uc_priv->gpio_count);
+
+ return 0;
+}
+
+static const struct dm_gpio_ops max7320_gpio_ops = {
+ .direction_output = max7320_direction_output,
+ .set_value = max7320_set_value,
+ .get_value = max7320_get_value,
+ .get_function = max7320_get_function,
+};
+
+static const struct udevice_id max7320_gpio_ids[] = {
+ { .compatible = "maxim,max7320" },
+ { }
+};
+
+U_BOOT_DRIVER(gpio_max7320) = {
+ .name = "gpio_max7320",
+ .id = UCLASS_GPIO,
+ .ops = &max7320_gpio_ops,
+ .of_match = max7320_gpio_ids,
+ .of_to_plat = max7320_ofdata_plat,
+ .probe = max7320_gpio_probe,
+ .plat_auto = sizeof(struct max7320_chip),
+};