1 files changed, 115 insertions, 0 deletions
diff --git a/drivers/net/ethernet/asix/ax88796c_spi.c b/drivers/net/ethernet/asix/ax88796c_spi.c
new file mode 100644
index 000000000000..94df4f96d2be
--- /dev/null
+++ b/drivers/net/ethernet/asix/ax88796c_spi.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2010 ASIX Electronics Corporation
+ * Copyright (c) 2020 Samsung Electronics Co., Ltd.
+ *
+ * ASIX AX88796C SPI Fast Ethernet Linux driver
+ */
+
+#define pr_fmt(fmt)	"ax88796c: " fmt
+
+#include <linux/string.h>
+#include <linux/spi/spi.h>
+
+#include "ax88796c_spi.h"
+
+const u8 ax88796c_rx_cmd_buf[5] = {AX_SPICMD_READ_RXQ, 0xFF, 0xFF, 0xFF, 0xFF};
+const u8 ax88796c_tx_cmd_buf[4] = {AX_SPICMD_WRITE_TXQ, 0xFF, 0xFF, 0xFF};
+
+/* driver bus management functions */
+int axspi_wakeup(struct axspi_data *ax_spi)
+{
+	int ret;
+
+	ax_spi->cmd_buf[0] = AX_SPICMD_EXIT_PWD;	/* OP */
+	ret = spi_write(ax_spi->spi, ax_spi->cmd_buf, 1);
+	if (ret)
+		dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
+	return ret;
+}
+
+int axspi_read_status(struct axspi_data *ax_spi, struct spi_status *status)
+{
+	int ret;
+
+	/* OP */
+	ax_spi->cmd_buf[0] = AX_SPICMD_READ_STATUS;
+	ret = spi_write_then_read(ax_spi->spi, ax_spi->cmd_buf, 1, (u8 *)&status, 3);
+	if (ret)
+		dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
+	else
+		le16_to_cpus(&status->isr);
+
+	return ret;
+}
+
+int axspi_read_rxq(struct axspi_data *ax_spi, void *data, int len)
+{
+	struct spi_transfer *xfer = ax_spi->spi_rx_xfer;
+	int ret;
+
+	memcpy(ax_spi->cmd_buf, ax88796c_rx_cmd_buf, 5);
+
+	xfer->tx_buf = ax_spi->cmd_buf;
+	xfer->rx_buf = NULL;
+	xfer->len = ax_spi->comp ? 2 : 5;
+	xfer->bits_per_word = 8;
+	spi_message_add_tail(xfer, &ax_spi->rx_msg);
+
+	xfer++;
+	xfer->rx_buf = data;
+	xfer->tx_buf = NULL;
+	xfer->len = len;
+	xfer->bits_per_word = 8;
+	spi_message_add_tail(xfer, &ax_spi->rx_msg);
+	ret = spi_sync(ax_spi->spi, &ax_spi->rx_msg);
+	if (ret)
+		dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
+
+	return ret;
+}
+
+int axspi_write_txq(const struct axspi_data *ax_spi, void *data, int len)
+{
+	return spi_write(ax_spi->spi, data, len);
+}
+
+u16 axspi_read_reg(struct axspi_data *ax_spi, u8 reg)
+{
+	int ret;
+	int len = ax_spi->comp ? 3 : 4;
+
+	ax_spi->cmd_buf[0] = 0x03;	/* OP code read register */
+	ax_spi->cmd_buf[1] = reg;	/* register address */
+	ax_spi->cmd_buf[2] = 0xFF;	/* dumy cycle */
+	ax_spi->cmd_buf[3] = 0xFF;	/* dumy cycle */
+	ret = spi_write_then_read(ax_spi->spi,
+				  ax_spi->cmd_buf, len,
+				  ax_spi->rx_buf, 2);
+	if (ret) {
+		dev_err(&ax_spi->spi->dev,
+			"%s() failed: ret = %d\n", __func__, ret);
+		return 0xFFFF;
+	}
+
+	le16_to_cpus((u16 *)ax_spi->rx_buf);
+
+	return *(u16 *)ax_spi->rx_buf;
+}
+
+int axspi_write_reg(struct axspi_data *ax_spi, u8 reg, u16 value)
+{
+	int ret;
+
+	memset(ax_spi->cmd_buf, 0, sizeof(ax_spi->cmd_buf));
+	ax_spi->cmd_buf[0] = AX_SPICMD_WRITE_REG;	/* OP code read register */
+	ax_spi->cmd_buf[1] = reg;			/* register address */
+	ax_spi->cmd_buf[2] = value;
+	ax_spi->cmd_buf[3] = value >> 8;
+
+	ret = spi_write(ax_spi->spi, ax_spi->cmd_buf, 4);
+	if (ret)
+		dev_err(&ax_spi->spi->dev, "%s() failed: ret = %d\n", __func__, ret);
+	return ret;
+}
+