static int cyttsp4_spi_xfer(u8 op, struct cyttsp4_spi *ts,
u16 reg, u8 *buf, int length)
{
struct device *dev = &ts->client->dev;
struct spi_message msg;
struct spi_transfer xfer[2];
u8 wr_hdr_buf[CY_SPI_MAX_HEADER_BYTES];
u8 rd_hdr_buf[CY_SPI_MAX_HEADER_BYTES];
int rc;
memset(wr_hdr_buf, 0, CY_SPI_MAX_HEADER_BYTES);
memset(rd_hdr_buf, 0, CY_SPI_MAX_HEADER_BYTES);
memset(xfer, 0, sizeof(xfer));
spi_message_init(&msg);
/* Header buffer */
xfer[0].tx_buf = wr_hdr_buf;
xfer[0].rx_buf = rd_hdr_buf;
switch (op) {
case CY_SPI_WR_OP:
if (length + CY_SPI_WR_HEADER_BYTES > CY_SPI_DATA_SIZE) {
dev_vdbg(dev,
"%s: length+%d=%d is greater than SPI max=%d\n",
__func__, CY_SPI_WR_HEADER_BYTES,
length + CY_SPI_WR_HEADER_BYTES,
CY_SPI_DATA_SIZE);
rc = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
/* Header byte 0 */
if (reg > 255)
wr_hdr_buf[0] = CY_SPI_WR_OP + CY_SPI_A8_BIT;
else
wr_hdr_buf[0] = CY_SPI_WR_OP;
/* Header byte 1 */
wr_hdr_buf[1] = reg % 256;
xfer[0].len = CY_SPI_WR_HEADER_BYTES;
spi_message_add_tail(&xfer[0], &msg);
/* Data buffer */
if (buf) {
xfer[1].tx_buf = buf;
xfer[1].len = length;
spi_message_add_tail(&xfer[1], &msg);
}
break;
case CY_SPI_RD_OP:
if (!buf) {
dev_err(dev, "%s: No read buffer\n", __func__);
rc = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
if ((length + CY_SPI_RD_HEADER_BYTES) > CY_SPI_DATA_SIZE) {
dev_vdbg(dev,
"%s: length+%d=%d is greater than SPI max=%d\n",
__func__, CY_SPI_RD_HEADER_BYTES,
length + CY_SPI_RD_HEADER_BYTES,
CY_SPI_DATA_SIZE);
rc = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
/* Header byte 0 */
wr_hdr_buf[0] = CY_SPI_RD_OP;
xfer[0].len = CY_SPI_RD_HEADER_BYTES;
spi_message_add_tail(&xfer[0], &msg);
/* Data buffer */
xfer[1].rx_buf = buf;
xfer[1].len = length;
spi_message_add_tail(&xfer[1], &msg);
break;
default:
dev_dbg(dev, "%s: bad op code=%d\n", __func__, op);
rc = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
rc = spi_sync(ts->client, &msg);
if (rc < 0) {
dev_vdbg(dev, "%s: spi_sync() error %d, len=%d, op=%d\n",
__func__, rc, xfer[0].len, op);
/*
* do not return here since probably a bad ACK sequence
* let the following ACK check handle any errors and
* allow silent retries
*/
}
if (rd_hdr_buf[CY_SPI_SYNC_BYTE] != CY_SPI_SYNC_ACK) {
/* signal ACK error so silent retry */
rc = 1;
switch (op) {
case CY_SPI_WR_OP:
_cyttsp4_spi_pr_buf(ts, wr_hdr_buf,
CY_SPI_WR_HEADER_BYTES,
"spi_wr_buf HEAD");
if (buf)
_cyttsp4_spi_pr_buf(ts, buf,
length, "spi_wr_buf DATA");
break;
case CY_SPI_RD_OP:
_cyttsp4_spi_pr_buf(ts, rd_hdr_buf,
CY_SPI_RD_HEADER_BYTES, "spi_rd_buf HEAD");
_cyttsp4_spi_pr_buf(ts, buf, length,
"spi_rd_buf DATA");
break;
default:
/*
* should not get here due to error check
* in first switch
*/
break;
}
}
cyttsp4_spi_xfer_exit:
return rc;
}
static int cyttsp4_spi_xfer(u8 op, struct cyttsp4_spi *ts,
u16 reg, u8 *buf, int length)
{
struct spi_message msg;
struct spi_transfer xfer[2];
int retval;
memset(ts->wr_buf, 0, length + CY_SPI_WR_HEADER_BYTES);
memset(ts->rd_buf, 0, length + CY_SPI_RD_HEADER_BYTES);
memset(xfer, 0, sizeof(xfer));
spi_message_init(&msg);
xfer[0].tx_buf = ts->wr_buf;
xfer[0].rx_buf = ts->rd_buf;
switch (op) {
case CY_SPI_WR_OP:
if ((length + CY_SPI_WR_HEADER_BYTES) > CY_SPI_DATA_SIZE) {
dev_vdbg(ts->bus_ops.dev,
"%s: length+%d=%d is greater than SPI max=%d\n",
__func__, CY_SPI_WR_HEADER_BYTES,
length + CY_SPI_WR_HEADER_BYTES,
CY_SPI_DATA_SIZE);
retval = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
/* header byte 0 */
if (reg / (CY_SPI_MAX_REG / 2))
ts->wr_buf[0] = CY_SPI_WR_OP + CY_SPI_A8_BIT;
else
ts->wr_buf[0] = CY_SPI_WR_OP;
/* header byte 1 */
ts->wr_buf[1] = reg % (CY_SPI_MAX_REG / 2);
if (buf != NULL)
memcpy(&ts->wr_buf[2], buf, length);
xfer[0].len = length + CY_SPI_WR_HEADER_BYTES;
spi_message_add_tail(&xfer[0], &msg);
break;
case CY_SPI_RD_OP:
if (buf == NULL) {
dev_err(ts->bus_ops.dev,
"%s: read return buf=%p\n", __func__, buf);
retval = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
if ((length + CY_SPI_RD_HEADER_BYTES) > CY_SPI_DATA_SIZE) {
dev_vdbg(ts->bus_ops.dev,
"%s: length+%d=%d is greater than SPI max=%d\n",
__func__, CY_SPI_RD_HEADER_BYTES,
length + CY_SPI_RD_HEADER_BYTES,
CY_SPI_DATA_SIZE);
retval = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
/* header byte 0 */
ts->wr_buf[0] = CY_SPI_RD_OP;
xfer[0].len = CY_SPI_RD_HEADER_BYTES;
spi_message_add_tail(&xfer[0], &msg);
xfer[1].rx_buf = buf;
xfer[1].len = length;
spi_message_add_tail(&xfer[1], &msg);
break;
default:
dev_dbg(ts->bus_ops.dev,
"%s: bad op code=%d\n", __func__, op);
retval = -EINVAL;
goto cyttsp4_spi_xfer_exit;
}
retval = spi_sync(ts->spi_client, &msg);
if (retval < 0) {
dev_vdbg(ts->bus_ops.dev,
"%s: spi_sync() error %d, len=%d, op=%d\n",
__func__, retval, xfer[0].len, op);
/*
* do not return here since probably a bad ACK sequence
* let the following ACK check handle any errors and
* allow silent retries
*/
}
if (ts->rd_buf[CY_SPI_SYNC_BYTE] != CY_SPI_SYNC_ACK) {
/* signal ACK error so silent retry */
retval = 1;
switch (op) {
case CY_SPI_WR_OP:
_cyttsp4_spi_pr_buf(ts, ts->wr_buf,
length + CY_SPI_WR_HEADER_BYTES, "spi_wr_buf");
break;
case CY_SPI_RD_OP:
_cyttsp4_spi_pr_buf(ts, ts->rd_buf,
length + CY_SPI_RD_HEADER_BYTES, "spi_rd_buf");
break;
default:
/*
* should not get here due to error check
* in first switch
*/
break;
}
} else
retval = 0;
cyttsp4_spi_xfer_exit:
return retval;
}
