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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 | // SPDX-License-Identifier: GPL-2.0-only /* * ---------------------------------------------------------------------------- * drivers/nfc/st95hf/spi.c function definitions for SPI communication * ---------------------------------------------------------------------------- * Copyright (C) 2015 STMicroelectronics Pvt. Ltd. All rights reserved. */ #include "spi.h" /* Function to send user provided buffer to ST95HF through SPI */ int st95hf_spi_send(struct st95hf_spi_context *spicontext, unsigned char *buffertx, int datalen, enum req_type reqtype) { struct spi_message m; int result = 0; struct spi_device *spidev = spicontext->spidev; struct spi_transfer tx_transfer = { .tx_buf = buffertx, .len = datalen, }; mutex_lock(&spicontext->spi_lock); if (reqtype == SYNC) { spicontext->req_issync = true; reinit_completion(&spicontext->done); } else { spicontext->req_issync = false; } spi_message_init(&m); spi_message_add_tail(&tx_transfer, &m); result = spi_sync(spidev, &m); if (result) { dev_err(&spidev->dev, "error: sending cmd to st95hf using SPI = %d\n", result); mutex_unlock(&spicontext->spi_lock); return result; } /* return for asynchronous or no-wait case */ if (reqtype == ASYNC) { mutex_unlock(&spicontext->spi_lock); return 0; } result = wait_for_completion_timeout(&spicontext->done, msecs_to_jiffies(1000)); /* check for timeout or success */ if (!result) { dev_err(&spidev->dev, "error: response not ready timeout\n"); result = -ETIMEDOUT; } else { result = 0; } mutex_unlock(&spicontext->spi_lock); return result; } EXPORT_SYMBOL_GPL(st95hf_spi_send); /* Function to Receive command Response */ int st95hf_spi_recv_response(struct st95hf_spi_context *spicontext, unsigned char *receivebuff) { int len = 0; struct spi_transfer tx_takedata; struct spi_message m; struct spi_device *spidev = spicontext->spidev; unsigned char readdata_cmd = ST95HF_COMMAND_RECEIVE; struct spi_transfer t[2] = { {.tx_buf = &readdata_cmd, .len = 1,}, {.rx_buf = receivebuff, .len = 2, .cs_change = 1,}, }; int ret = 0; memset(&tx_takedata, 0x0, sizeof(struct spi_transfer)); mutex_lock(&spicontext->spi_lock); /* First spi transfer to know the length of valid data */ spi_message_init(&m); spi_message_add_tail(&t[0], &m); spi_message_add_tail(&t[1], &m); ret = spi_sync(spidev, &m); if (ret) { dev_err(&spidev->dev, "spi_recv_resp, data length error = %d\n", ret); mutex_unlock(&spicontext->spi_lock); return ret; } /* As 2 bytes are already read */ len = 2; /* Support of long frame */ if (receivebuff[0] & 0x60) len += (((receivebuff[0] & 0x60) >> 5) << 8) | receivebuff[1]; else len += receivebuff[1]; /* Now make a transfer to read only relevant bytes */ tx_takedata.rx_buf = &receivebuff[2]; tx_takedata.len = len - 2; spi_message_init(&m); spi_message_add_tail(&tx_takedata, &m); ret = spi_sync(spidev, &m); mutex_unlock(&spicontext->spi_lock); if (ret) { dev_err(&spidev->dev, "spi_recv_resp, data read error = %d\n", ret); return ret; } return len; } EXPORT_SYMBOL_GPL(st95hf_spi_recv_response); int st95hf_spi_recv_echo_res(struct st95hf_spi_context *spicontext, unsigned char *receivebuff) { unsigned char readdata_cmd = ST95HF_COMMAND_RECEIVE; struct spi_transfer t[2] = { {.tx_buf = &readdata_cmd, .len = 1,}, {.rx_buf = receivebuff, .len = 1,}, }; struct spi_message m; struct spi_device *spidev = spicontext->spidev; int ret = 0; mutex_lock(&spicontext->spi_lock); spi_message_init(&m); spi_message_add_tail(&t[0], &m); spi_message_add_tail(&t[1], &m); ret = spi_sync(spidev, &m); mutex_unlock(&spicontext->spi_lock); if (ret) dev_err(&spidev->dev, "recv_echo_res, data read error = %d\n", ret); return ret; } EXPORT_SYMBOL_GPL(st95hf_spi_recv_echo_res); |