--- /dev/null
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2021 Michael Walle <michael@walle.cc>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <i2c.h>
+
+struct sl28cpld_child_plat {
+ uint offset;
+};
+
+/*
+ * The access methods works either with the first argument being a child
+ * device or with the MFD device itself.
+ */
+static int sl28cpld_read_child(struct udevice *dev, uint offset)
+{
+ struct sl28cpld_child_plat *plat = dev_get_parent_plat(dev);
+ struct udevice *mfd = dev_get_parent(dev);
+
+ return dm_i2c_reg_read(mfd, offset + plat->offset);
+}
+
+int sl28cpld_read(struct udevice *dev, uint offset)
+{
+ if (dev->driver == DM_DRIVER_GET(sl28cpld))
+ return dm_i2c_reg_read(dev, offset);
+ else
+ return sl28cpld_read_child(dev, offset);
+}
+
+static int sl28cpld_write_child(struct udevice *dev, uint offset,
+ uint8_t value)
+{
+ struct sl28cpld_child_plat *plat = dev_get_parent_plat(dev);
+ struct udevice *mfd = dev_get_parent(dev);
+
+ return dm_i2c_reg_write(mfd, offset + plat->offset, value);
+}
+
+int sl28cpld_write(struct udevice *dev, uint offset, uint8_t value)
+{
+ if (dev->driver == DM_DRIVER_GET(sl28cpld))
+ return dm_i2c_reg_write(dev, offset, value);
+ else
+ return sl28cpld_write_child(dev, offset, value);
+}
+
+int sl28cpld_update(struct udevice *dev, uint offset, uint8_t clear,
+ uint8_t set)
+{
+ int val;
+
+ val = sl28cpld_read(dev, offset);
+ if (val < 0)
+ return val;
+
+ val &= ~clear;
+ val |= set;
+
+ return sl28cpld_write(dev, offset, val);
+}
+
+static int sl28cpld_probe(struct udevice *dev)
+{
+ i2c_set_chip_flags(dev, DM_I2C_CHIP_RD_ADDRESS |
+ DM_I2C_CHIP_WR_ADDRESS);
+
+ return 0;
+}
+
+static int sl28cpld_child_post_bind(struct udevice *dev)
+{
+ struct sl28cpld_child_plat *plat = dev_get_parent_plat(dev);
+ int offset;
+
+ if (!dev_has_ofnode(dev))
+ return 0;
+
+ offset = dev_read_u32_default(dev, "reg", -1);
+ if (offset == -1)
+ return -EINVAL;
+
+ plat->offset = offset;
+
+ return 0;
+}
+
+static const struct udevice_id sl28cpld_ids[] = {
+ { .compatible = "kontron,sl28cpld" },
+ {}
+};
+
+U_BOOT_DRIVER(sl28cpld) = {
+ .name = "sl28cpld",
+ .id = UCLASS_NOP,
+ .of_match = sl28cpld_ids,
+ .probe = sl28cpld_probe,
+ .bind = dm_scan_fdt_dev,
+ .flags = DM_FLAG_PRE_RELOC,
+ .per_child_plat_auto = sizeof(struct sl28cpld_child_plat),
+ .child_post_bind = sl28cpld_child_post_bind,
+};