| Vignesh R | 6430eea | 2019-02-05 11:29:15 +0530 | [diff] [blame] | 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 | } |