--- /dev/null
+/*
+ * Copyright (c) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <power/pmic.h>
+#include <power/regulator.h>
+#include <power/tps65090.h>
+
+static int tps65090_fet_probe(struct udevice *dev)
+{
+ struct dm_regulator_uclass_platdata *uc_pdata;
+
+ uc_pdata = dev_get_uclass_platdata(dev);
+
+ uc_pdata->type = REGULATOR_TYPE_OTHER;
+ uc_pdata->mode_count = 0;
+
+ return 0;
+}
+
+static bool tps65090_fet_get_enable(struct udevice *dev)
+{
+ struct udevice *pmic = dev_get_parent(dev);
+ int ret, fet_id;
+
+ fet_id = dev->driver_data;
+ debug("%s: fet_id=%d\n", __func__, fet_id);
+
+ ret = pmic_reg_read(pmic, REG_FET_BASE + fet_id);
+ if (ret < 0)
+ return ret;
+
+ return ret & FET_CTRL_ENFET;
+}
+
+/**
+ * Set the power state for a FET
+ *
+ * @param pmic pmic structure for the tps65090
+ * @param fet_id FET number to set (1..MAX_FET_NUM)
+ * @param set 1 to power on FET, 0 to power off
+ * @return -EIO if we got a comms error, -EAGAIN if the FET failed to
+ * change state. If all is ok, returns 0.
+ */
+static int tps65090_fet_set(struct udevice *pmic, int fet_id, bool set)
+{
+ int retry;
+ u32 value;
+ int ret;
+
+ value = FET_CTRL_ADENFET | FET_CTRL_WAIT;
+ if (set)
+ value |= FET_CTRL_ENFET;
+
+ if (pmic_reg_write(pmic, REG_FET_BASE + fet_id, value))
+ return -EIO;
+
+ /* Try reading until we get a result */
+ for (retry = 0; retry < MAX_CTRL_READ_TRIES; retry++) {
+ ret = pmic_reg_read(pmic, REG_FET_BASE + fet_id);
+ if (ret < 0)
+ return ret;
+
+ /* Check that the FET went into the expected state */
+ debug("%s: flags=%x\n", __func__, ret);
+ if (!!(ret & FET_CTRL_PGFET) == set)
+ return 0;
+
+ /* If we got a timeout, there is no point in waiting longer */
+ if (ret & FET_CTRL_TOFET)
+ break;
+
+ mdelay(1);
+ }
+
+ debug("FET %d: Power good should have set to %d but reg=%#02x\n",
+ fet_id, set, ret);
+ return -EAGAIN;
+}
+
+static int tps65090_fet_set_enable(struct udevice *dev, bool enable)
+{
+ struct udevice *pmic = dev_get_parent(dev);
+ int ret, fet_id;
+ ulong start;
+ int loops;
+
+ fet_id = dev->driver_data;
+ debug("%s: fet_id=%d, enable=%d\n", __func__, fet_id, enable);
+
+ start = get_timer(0);
+ for (loops = 0;; loops++) {
+ ret = tps65090_fet_set(pmic, fet_id, enable);
+ if (!ret)
+ break;
+
+ if (get_timer(start) > 100)
+ break;
+
+ /* Turn it off and try again until we time out */
+ tps65090_fet_set(pmic, fet_id, false);
+ }
+
+ if (ret)
+ debug("%s: FET%d failed to power on: time=%lums, loops=%d\n",
+ __func__, fet_id, get_timer(start), loops);
+ else if (loops)
+ debug("%s: FET%d powered on after %lums, loops=%d\n",
+ __func__, fet_id, get_timer(start), loops);
+
+ /*
+ * Unfortunately there are some conditions where the power-good bit
+ * will be 0, but the FET still comes up. One such case occurs with
+ * the LCD backlight on snow. We'll just return 0 here and assume
+ * that the FET will eventually come up.
+ */
+ if (ret == -EAGAIN)
+ ret = 0;
+
+ return ret;
+}
+
+static const struct dm_regulator_ops tps65090_fet_ops = {
+ .get_enable = tps65090_fet_get_enable,
+ .set_enable = tps65090_fet_set_enable,
+};
+
+U_BOOT_DRIVER(tps65090_fet) = {
+ .name = TPS65090_FET_DRIVER,
+ .id = UCLASS_REGULATOR,
+ .ops = &tps65090_fet_ops,
+ .probe = tps65090_fet_probe,
+};