mtd: spi-nor: fix spi_nor_spimem_setup_op() call in spi_nor_erase_{sector,chip}()

For erase operations, reg_proto must be used as indicated in
struct spi_nor description in spi-nor.h.

This issue was found when DT property spi-tx-bus-width is set to 4.
In this case the spi_mem_op->addr.buswidth is set to 4 for erase command
which is not correct.

Tested on stm32mp157c-ev1 board with mx66l51235f spi-nor.

Fixes: 0e30f47 ("mtd: spi-nor: add support for DTR protocol")
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>
[ta: use nor->reg_proto in spi_nor_controller_ops_erase()]
Signed-off-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Tested-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Reviewed-by: Pratyush Yadav <p.yadav@ti.com>
Link: https://lore.kernel.org/r/20220629133013.3382393-1-patrice.chotard@foss.st.com

Author: Patrice Chotard

drivers/mtd/spi-nor/core.c

@@ -177,7 +177,7 @@ int spi_nor_controller_ops_write_reg(struct spi_nor *nor, u8 opcode,
 
 static int spi_nor_controller_ops_erase(struct spi_nor *nor, loff_t offs)
 {
-	if (spi_nor_protocol_is_dtr(nor->write_proto))
+	if (spi_nor_protocol_is_dtr(nor->reg_proto))
 		return -EOPNOTSUPP;
 
 	return nor->controller_ops->erase(nor, offs);
@@ -972,7 +972,7 @@ static int spi_nor_erase_chip(struct spi_nor *nor)
 	if (nor->spimem) {
 		struct spi_mem_op op = SPI_NOR_CHIP_ERASE_OP;
 
-		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
 		ret = spi_mem_exec_op(nor->spimem, &op);
 	} else {
@@ -1115,7 +1115,7 @@ int spi_nor_erase_sector(struct spi_nor *nor, u32 addr)
 			SPI_NOR_SECTOR_ERASE_OP(nor->erase_opcode,
 						nor->addr_nbytes, addr);
 
-		spi_nor_spimem_setup_op(nor, &op, nor->write_proto);
+		spi_nor_spimem_setup_op(nor, &op, nor->reg_proto);
 
 		return spi_mem_exec_op(nor->spimem, &op);
 	} else if (nor->controller_ops->erase) {