spi: Add non DM version of SPI_MEM

Add non DM version of SPI_MEM to support easy migration to new SPI NOR
framework. This can be removed once DM_SPI conversion is complete.

Signed-off-by: Vignesh R <vigneshr@ti.com>
Tested-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Tested-by: Stefan Roese <sr@denx.de>
Tested-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>
Tested-by: Jagan Teki <jagan@amarulasolutions.com> #zynq-microzed
diff --git a/drivers/spi/spi-mem-nodm.c b/drivers/spi/spi-mem-nodm.c
new file mode 100644
index 0000000..4447d44
--- /dev/null
+++ b/drivers/spi/spi-mem-nodm.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#include <spi.h>
+#include <spi-mem.h>
+
+int spi_mem_exec_op(struct spi_slave *slave,
+		    const struct spi_mem_op *op)
+{
+	unsigned int pos = 0;
+	const u8 *tx_buf = NULL;
+	u8 *rx_buf = NULL;
+	u8 *op_buf;
+	int op_len;
+	u32 flag;
+	int ret;
+	int i;
+
+	if (op->data.nbytes) {
+		if (op->data.dir == SPI_MEM_DATA_IN)
+			rx_buf = op->data.buf.in;
+		else
+			tx_buf = op->data.buf.out;
+	}
+
+	op_len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
+	op_buf = calloc(1, op_len);
+
+	ret = spi_claim_bus(slave);
+	if (ret < 0)
+		return ret;
+
+	op_buf[pos++] = op->cmd.opcode;
+
+	if (op->addr.nbytes) {
+		for (i = 0; i < op->addr.nbytes; i++)
+			op_buf[pos + i] = op->addr.val >>
+				(8 * (op->addr.nbytes - i - 1));
+
+		pos += op->addr.nbytes;
+	}
+
+	if (op->dummy.nbytes)
+		memset(op_buf + pos, 0xff, op->dummy.nbytes);
+
+	/* 1st transfer: opcode + address + dummy cycles */
+	flag = SPI_XFER_BEGIN;
+	/* Make sure to set END bit if no tx or rx data messages follow */
+	if (!tx_buf && !rx_buf)
+		flag |= SPI_XFER_END;
+
+	ret = spi_xfer(slave, op_len * 8, op_buf, NULL, flag);
+	if (ret)
+		return ret;
+
+	/* 2nd transfer: rx or tx data path */
+	if (tx_buf || rx_buf) {
+		ret = spi_xfer(slave, op->data.nbytes * 8, tx_buf,
+			       rx_buf, SPI_XFER_END);
+		if (ret)
+			return ret;
+	}
+
+	spi_release_bus(slave);
+
+	for (i = 0; i < pos; i++)
+		debug("%02x ", op_buf[i]);
+	debug("| [%dB %s] ",
+	      tx_buf || rx_buf ? op->data.nbytes : 0,
+	      tx_buf || rx_buf ? (tx_buf ? "out" : "in") : "-");
+	for (i = 0; i < op->data.nbytes; i++)
+		debug("%02x ", tx_buf ? tx_buf[i] : rx_buf[i]);
+	debug("[ret %d]\n", ret);
+
+	free(op_buf);
+
+	if (ret < 0)
+		return ret;
+
+	return 0;
+}
+
+int spi_mem_adjust_op_size(struct spi_slave *slave,
+			   struct spi_mem_op *op)
+{
+	unsigned int len;
+
+	len = sizeof(op->cmd.opcode) + op->addr.nbytes + op->dummy.nbytes;
+	if (slave->max_write_size && len > slave->max_write_size)
+		return -EINVAL;
+
+	if (op->data.dir == SPI_MEM_DATA_IN && slave->max_read_size)
+		op->data.nbytes = min(op->data.nbytes,
+				      slave->max_read_size);
+	else if (slave->max_write_size)
+		op->data.nbytes = min(op->data.nbytes,
+				      slave->max_write_size - len);
+
+	if (!op->data.nbytes)
+		return -EINVAL;
+
+	return 0;
+}