1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright (c) 2020 Foundries.io Ltd
4  */
5 
6 #include <common.h>
7 #include <dm.h>
8 #include <i2c.h>
9 #include <tee.h>
10 #include "optee_msg.h"
11 #include "optee_private.h"
12 
check_xfer_flags(struct udevice * chip,uint tee_flags)13 static int check_xfer_flags(struct udevice *chip, uint tee_flags)
14 {
15 	uint flags;
16 	int ret;
17 
18 	ret = i2c_get_chip_flags(chip, &flags);
19 	if (ret)
20 		return ret;
21 
22 	if (tee_flags & OPTEE_MSG_RPC_CMD_I2C_FLAGS_TEN_BIT) {
23 		if (!(flags & DM_I2C_CHIP_10BIT))
24 			return -EINVAL;
25 	} else {
26 		if (flags & DM_I2C_CHIP_10BIT)
27 			return -EINVAL;
28 	}
29 
30 	return 0;
31 }
32 
optee_suppl_cmd_i2c_transfer(struct optee_msg_arg * arg)33 void optee_suppl_cmd_i2c_transfer(struct optee_msg_arg *arg)
34 {
35 	const u8 attr[] = {
36 		OPTEE_MSG_ATTR_TYPE_VALUE_INPUT,
37 		OPTEE_MSG_ATTR_TYPE_VALUE_INPUT,
38 		OPTEE_MSG_ATTR_TYPE_RMEM_INOUT,
39 		OPTEE_MSG_ATTR_TYPE_VALUE_OUTPUT,
40 	};
41 	struct udevice *chip_dev;
42 	struct tee_shm *shm;
43 	u8 *buf;
44 	int ret;
45 
46 	if (arg->num_params != ARRAY_SIZE(attr) ||
47 	    arg->params[0].attr != attr[0] ||
48 	    arg->params[1].attr != attr[1] ||
49 	    arg->params[2].attr != attr[2] ||
50 	    arg->params[3].attr != attr[3]) {
51 		goto bad;
52 	}
53 
54 	shm = (struct tee_shm *)(unsigned long)arg->params[2].u.rmem.shm_ref;
55 	buf = shm->addr;
56 	if (!buf)
57 		goto bad;
58 
59 	if (i2c_get_chip_for_busnum((int)arg->params[0].u.value.b,
60 				    (int)arg->params[0].u.value.c,
61 				    0, &chip_dev))
62 		goto bad;
63 
64 	if (check_xfer_flags(chip_dev, arg->params[1].u.value.a))
65 		goto bad;
66 
67 	switch (arg->params[0].u.value.a) {
68 	case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_RD:
69 		ret = dm_i2c_read(chip_dev, 0, buf,
70 				  (size_t)arg->params[2].u.rmem.size);
71 		break;
72 	case OPTEE_MSG_RPC_CMD_I2C_TRANSFER_WR:
73 		ret = dm_i2c_write(chip_dev, 0, buf,
74 				   (size_t)arg->params[2].u.rmem.size);
75 		break;
76 	default:
77 		goto bad;
78 	}
79 
80 	if (ret) {
81 		arg->ret = TEE_ERROR_COMMUNICATION;
82 	} else {
83 		arg->params[3].u.value.a = arg->params[2].u.rmem.size;
84 		arg->ret = TEE_SUCCESS;
85 	}
86 
87 	return;
88 bad:
89 	arg->ret = TEE_ERROR_BAD_PARAMETERS;
90 }
91