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path: root/drivers/nfc/st95hf/spi.c
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Diffstat (limited to 'drivers/nfc/st95hf/spi.c')
-rw-r--r--drivers/nfc/st95hf/spi.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/drivers/nfc/st95hf/spi.c b/drivers/nfc/st95hf/spi.c
new file mode 100644
index 000000000..e2d3bbcc8
--- /dev/null
+++ b/drivers/nfc/st95hf/spi.c
@@ -0,0 +1,167 @@
+/*
+ * ----------------------------------------------------------------------------
+ * drivers/nfc/st95hf/spi.c function definitions for SPI communication
+ * ----------------------------------------------------------------------------
+ * Copyright (C) 2015 STMicroelectronics Pvt. Ltd. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#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);