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
spi_mem_exec_op(struct spi_slave * slave,const struct spi_mem_op * op)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
spi_mem_adjust_op_size(struct spi_slave * slave,struct spi_mem_op * op)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