[PATCH v3 13/14] mtd: spi-nor: core: execute command sequences to change octal DTR mode

[Mason Yang <masonccyang@xxxxxxxxxxx>]

Execute command sequences to change octal DTR mode.

Signed-off-by: Mason Yang <masonccyang@xxxxxxxxxxx>
---
 drivers/mtd/spi-nor/core.c | 71 ++++++++++++++++++++++++++++++++++++++++++++++
 drivers/mtd/spi-nor/core.h |  3 ++
 2 files changed, 74 insertions(+)

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index a353830..caac58cd 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -425,6 +425,77 @@ int spi_nor_write_cr2(struct spi_nor *nor, u32 addr, u8 *cr2)
 }
 
 /**
+ * spi_nor_cmd_seq_octal_dtr() - command sequences to change to octal DTR mode
+ * @nor:	pointer to 'struct spi_nor'.
+ * @enable:	enable Octal DTR.
+ *
+ * Return: 0 on success, -errno otherwise.
+ */
+int spi_nor_cmd_seq_octal_dtr(struct spi_nor *nor, bool enable)
+{
+	struct spi_nor_flash_parameter *p = nor->params;
+	struct cmd_seq_octal_dtr *cs = p->cmd_seq;
+	int i, ret;
+	struct spi_mem_op op;
+
+	if (!nor->spimem || !p->cmd_seq[0].len)
+		return -ENOTSUPP;
+
+	if (!enable)
+		return 0;
+
+	for (i = 0; i < CMD_SEQ_OCTAL_DTR_DWORD_LEN; i++) {
+		switch (p->cmd_seq[i].len) {
+		case 1:
+			op = (struct spi_mem_op)
+				SPI_MEM_OP(SPI_MEM_OP_CMD(cs[i].opcode, 1),
+					   SPI_MEM_OP_NO_ADDR,
+					   SPI_MEM_OP_NO_DUMMY,
+					   SPI_MEM_OP_NO_DATA);
+
+			ret = spi_mem_exec_op(nor->spimem, &op);
+			if (ret)
+				return ret;
+			break;
+
+		case 3:
+			op = (struct spi_mem_op)
+				SPI_MEM_OP(SPI_MEM_OP_CMD(cs[i].opcode, 1),
+					   SPI_MEM_OP_ADDR(1, cs[i].addr, 1),
+					   SPI_MEM_OP_NO_DUMMY,
+					   SPI_MEM_OP_DATA_OUT(1,
+							       &cs[i].data, 1));
+
+			ret = spi_mem_exec_op(nor->spimem, &op);
+			if (ret)
+				return ret;
+			break;
+
+		case 6:
+			op = (struct spi_mem_op)
+				SPI_MEM_OP(SPI_MEM_OP_CMD(cs[i].opcode, 1),
+					   SPI_MEM_OP_ADDR(4, cs[i].addr, 1),
+					   SPI_MEM_OP_NO_DUMMY,
+					   SPI_MEM_OP_DATA_OUT(1,
+							       &cs[i].data, 1));
+
+			ret = spi_mem_exec_op(nor->spimem, &op);
+			if (ret)
+				return ret;
+			break;
+
+		default:
+			dev_err(nor->dev,
+				"Error %d sequences to Octal DTR\n",
+				p->cmd_seq[i].len);
+			break;
+		}
+	}
+
+	return ret;
+}
+
+/**
  * spi_nor_read_sr() - Read the Status Register.
  * @nor:	pointer to 'struct spi_nor'.
  * @sr:		pointer to a DMA-able buffer where the value of the
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 9b0e0ba..b47bc44d 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -199,6 +199,8 @@ struct cmd_seq_octal_dtr {
 	u8 data;
 };
 
+#define CMD_SEQ_OCTAL_DTR_DWORD_LEN	4
+
 /**
  * struct spi_nor_flash_parameter - SPI NOR flash parameters and settings.
  * Includes legacy flash parameters and settings that can be overwritten
@@ -442,6 +444,7 @@ void spi_nor_spimem_setup_op(const struct spi_nor *nor,
 int spi_nor_write_disable(struct spi_nor *nor);
 int spi_nor_read_cr2(struct spi_nor *nor, u32 addr, u8 *cr2);
 int spi_nor_write_cr2(struct spi_nor *nor, u32 addr, u8 *cr2);
+int spi_nor_cmd_seq_octal_dtr(struct spi_nor *nor, bool enable);
 int spi_nor_set_4byte_addr_mode(struct spi_nor *nor, bool enable);
 int spi_nor_write_ear(struct spi_nor *nor, u8 ear);
 int spi_nor_wait_till_ready(struct spi_nor *nor);
-- 
1.9.1