[people/ms/u-boot.git] / drivers / i2c / cros_ec_ldo.c

/*
 * Copyright (c) 2015 Google, Inc
 * Written by Simon Glass <sjg@chromium.org>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <dm.h>
#include <cros_ec.h>
#include <errno.h>
#include <i2c.h>
#include <power/tps65090.h>

static int cros_ec_ldo_set_bus_speed(struct udevice *dev, unsigned int speed)
{
	return 0;
}

static int cros_ec_ldo_xfer(struct udevice *dev, struct i2c_msg *msg,
			    int nmsgs)
{
	bool is_read = nmsgs > 1;
	int fet_id, ret;

	/*
	 * Look for reads and writes of the LDO registers. In either case the
	 * first message is a write with the register number as the first byte.
	 */
	if (!nmsgs || !msg->len || (msg->flags & I2C_M_RD)) {
		debug("%s: Invalid message\n", __func__);
		goto err;
	}

	fet_id = msg->buf[0] - REG_FET_BASE;
	if (fet_id < 1 || fet_id > MAX_FET_NUM) {
		debug("%s: Invalid FET %d\n", __func__, fet_id);
		goto err;
	}

	if (is_read) {
		uint8_t state;

		ret = cros_ec_get_ldo(dev->parent, fet_id, &state);
		if (!ret)
			msg[1].buf[0] = state ?
				FET_CTRL_ENFET | FET_CTRL_PGFET : 0;
	} else {
		bool on = msg->buf[1] & FET_CTRL_ENFET;

		ret = cros_ec_set_ldo(dev->parent, fet_id, on);
	}

	return ret;

err:
	/* Indicate that the message is unimplemented */
	return -ENOSYS;
}

static const struct dm_i2c_ops cros_ec_i2c_ops = {
	.xfer		= cros_ec_ldo_xfer,
	.set_bus_speed	= cros_ec_ldo_set_bus_speed,
};

static const struct udevice_id cros_ec_i2c_ids[] = {
	{ .compatible = "google,cros-ec-ldo-tunnel" },
	{ }
};

U_BOOT_DRIVER(cros_ec_ldo) = {
	.name	= "cros_ec_ldo_tunnel",
	.id	= UCLASS_I2C,
	.of_match = cros_ec_i2c_ids,
	.ops	= &cros_ec_i2c_ops,
};
Commit	Line	Data
f48eaf01 SG	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
	15	static int cros_ec_ldo_set_bus_speed(struct udevice *dev, unsigned int speed)
	16	{
	17	return 0;
	18	}
	19
	20	static 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
	56	err:
	57	/* Indicate that the message is unimplemented */
	58	return -ENOSYS;
	59	}
	60
	61	static 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
66	static const struct udevice_id cros_ec_i2c_ids[] = {
67	{ .compatible = "google,cros-ec-ldo-tunnel" },
68	{ }
69	};
70
71	U_BOOT_DRIVER(cros_ec_ldo) = {
72	.name = "cros_ec_ldo_tunnel",
73	.id = UCLASS_I2C,
74	.of_match = cros_ec_i2c_ids,
f48eaf01 SG	75	.ops = &cros_ec_i2c_ops,
f48eaf01 SG	76	};