LXR uboot/drivers/i2c/cros_ec

   1/*
   2 * Copyright (c) 2015 Google, Inc
   3 * Written by Simon Glass <sjg@chromium.org>
   4 *
   5 * SPDX-License-Identifier:     GPL-2.0+
   6 */
   7
   8#include <common.h>
   9#include <dm.h>
  10#include <cros_ec.h>
  11#include <errno.h>
  12#include <i2c.h>
  13#include <power/tps65090.h>
  14
  15static int cros_ec_ldo_set_bus_speed(struct udevice *dev, unsigned int speed)
  16{
  17        return 0;
  18}
  19
  20static int cros_ec_ldo_xfer(struct udevice *dev, struct i2c_msg *msg,
  21                            int nmsgs)
  22{
  23        bool is_read = nmsgs > 1;
  24        int fet_id, ret;
  25
  26        /*
  27         * Look for reads and writes of the LDO registers. In either case the
  28         * first message is a write with the register number as the first byte.
  29         */
  30        if (!nmsgs || !msg->len || (msg->flags & I2C_M_RD)) {
  31                debug("%s: Invalid message\n", __func__);
  32                goto err;
  33        }
  34
  35        fet_id = msg->buf[0] - REG_FET_BASE;
  36        if (fet_id < 1 || fet_id > MAX_FET_NUM) {
  37                debug("%s: Invalid FET %d\n", __func__, fet_id);
  38                goto err;
  39        }
  40
  41        if (is_read) {
  42                uint8_t state;
  43
  44                ret = cros_ec_get_ldo(dev->parent, fet_id, &state);
  45                if (!ret)
  46                        msg[1].buf[0] = state ?
  47                                FET_CTRL_ENFET | FET_CTRL_PGFET : 0;
  48        } else {
  49                bool on = msg->buf[1] & FET_CTRL_ENFET;
  50
  51                ret = cros_ec_set_ldo(dev->parent, fet_id, on);
  52        }
  53
  54        return ret;
  55
  56err:
  57        /* Indicate that the message is unimplemented */
  58        return -ENOSYS;
  59}
  60
  61static const struct dm_i2c_ops cros_ec_i2c_ops = {
  62        .xfer           = cros_ec_ldo_xfer,
  63        .set_bus_speed  = cros_ec_ldo_set_bus_speed,
  64};
  65
  66static const struct udevice_id cros_ec_i2c_ids[] = {
  67        { .compatible = "google,cros-ec-ldo-tunnel" },
  68        { }
  69};
  70
  71U_BOOT_DRIVER(cros_ec_ldo) = {
  72        .name   = "cros_ec_ldo_tunnel",
  73        .id     = UCLASS_I2C,
  74        .of_match = cros_ec_i2c_ids,
  75        .per_child_auto_alloc_size = sizeof(struct dm_i2c_chip),
  76        .ops    = &cros_ec_i2c_ops,
  77};
  78