xref: /openbmc/u-boot/drivers/spi/spi-mem-nodm.c (revision fd0bc623)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
4  */
5 
6 #include <spi.h>
7 #include <spi-mem.h>
8 
9 int spi_mem_exec_op(struct spi_slave *slave,
10 		    const struct spi_mem_op *op)
11 {
12 	unsigned int pos = 0;
13 	const u8 *tx_buf = NULL;
14 	u8 *rx_buf = NULL;
15 	u8 *op_buf;
16 	int op_len;
17 	u32 flag;
18 	int ret;
19 	int i;
20 
21 	if (op->data.nbytes) {
22 		if (op->data.dir == SPI_MEM_DATA_IN)
23 			rx_buf = op->data.buf.in;
24 		else
25 			tx_buf = op->data.buf.out;
26 	}
27 
28 	op_len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
29 	op_buf = calloc(1, op_len);
30 
31 	ret = spi_claim_bus(slave);
32 	if (ret < 0)
33 		return ret;
34 
35 	op_buf[pos++] = op->cmd.opcode;
36 
37 	if (op->addr.nbytes) {
38 		for (i = 0; i < op->addr.nbytes; i++)
39 			op_buf[pos + i] = op->addr.val >>
40 				(8 * (op->addr.nbytes - i - 1));
41 
42 		pos += op->addr.nbytes;
43 	}
44 
45 	if (op->dummy.nbytes)
46 		memset(op_buf + pos, 0xff, op->dummy.nbytes);
47 
48 	/* 1st transfer: opcode + address + dummy cycles */
49 	flag = SPI_XFER_BEGIN;
50 	/* Make sure to set END bit if no tx or rx data messages follow */
51 	if (!tx_buf && !rx_buf)
52 		flag |= SPI_XFER_END;
53 
54 	ret = spi_xfer(slave, op_len * 8, op_buf, NULL, flag);
55 	if (ret)
56 		return ret;
57 
58 	/* 2nd transfer: rx or tx data path */
59 	if (tx_buf || rx_buf) {
60 		ret = spi_xfer(slave, op->data.nbytes * 8, tx_buf,
61 			       rx_buf, SPI_XFER_END);
62 		if (ret)
63 			return ret;
64 	}
65 
66 	spi_release_bus(slave);
67 
68 	for (i = 0; i < pos; i++)
69 		debug("%02x ", op_buf[i]);
70 	debug("| [%dB %s] ",
71 	      tx_buf || rx_buf ? op->data.nbytes : 0,
72 	      tx_buf || rx_buf ? (tx_buf ? "out" : "in") : "-");
73 	for (i = 0; i < op->data.nbytes; i++)
74 		debug("%02x ", tx_buf ? tx_buf[i] : rx_buf[i]);
75 	debug("[ret %d]\n", ret);
76 
77 	free(op_buf);
78 
79 	if (ret < 0)
80 		return ret;
81 
82 	return 0;
83 }
84 
85 int spi_mem_adjust_op_size(struct spi_slave *slave,
86 			   struct spi_mem_op *op)
87 {
88 	unsigned int len;
89 
90 	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
91 	if (slave->max_write_size && len > slave->max_write_size)
92 		return -EINVAL;
93 
94 	if (op->data.dir == SPI_MEM_DATA_IN && slave->max_read_size)
95 		op->data.nbytes = min(op->data.nbytes,
96 				      slave->max_read_size);
97 	else if (slave->max_write_size)
98 		op->data.nbytes = min(op->data.nbytes,
99 				      slave->max_write_size - len);
100 
101 	if (!op->data.nbytes)
102 		return -EINVAL;
103 
104 	return 0;
105 }
106