spi: hisi-sfc-v3xx: factor out bus config and transfer functions

In hisi_sfc_v3xx_generic_exec_op(), we will write the data to the buffer,
configure and start the transfer, read the data to the buffer and check
whether occurs an error. Factor out the config and transfer start codes
as individual functions, to make the process a bit clearer.
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/1600950270-52536-3-git-send-email-yangyicong@hisilicon.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/spi-hisi-sfc-v3xx.c

@@ -198,12 +198,12 @@ static void hisi_sfc_v3xx_write_databuf(struct hisi_sfc_v3xx_host *host,
 	}
 }
 
-static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
-					 const struct spi_mem_op *op,
-					 u8 chip_select)
+static int hisi_sfc_v3xx_start_bus(struct hisi_sfc_v3xx_host *host,
+				   const struct spi_mem_op *op,
+				   u8 chip_select)
 {
-	int ret = 0, len = op->data.nbytes, buswidth_mode;
-	u32 int_stat, config = 0;
+	int len = op->data.nbytes, buswidth_mode;
+	u32 config = 0;
 
 	if (op->addr.nbytes)
 		config |= HISI_SFC_V3XX_CMD_CFG_ADDR_EN_MSK;
@@ -227,9 +227,7 @@ static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
 		config |= HISI_SFC_V3XX_CMD_CFG_DATA_EN_MSK;
 	}
 
-	if (op->data.dir == SPI_MEM_DATA_OUT)
-		hisi_sfc_v3xx_write_databuf(host, op->data.buf.out, len);
-	else if (op->data.dir == SPI_MEM_DATA_IN)
+	if (op->data.dir == SPI_MEM_DATA_IN)
 		config |= HISI_SFC_V3XX_CMD_CFG_RW_MSK;
 
 	config |= op->dummy.nbytes << HISI_SFC_V3XX_CMD_CFG_DUMMY_CNT_OFF |
@@ -241,6 +239,23 @@ static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
 
 	writel(config, host->regbase + HISI_SFC_V3XX_CMD_CFG);
 
+	return 0;
+}
+
+static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
+					 const struct spi_mem_op *op,
+					 u8 chip_select)
+{
+	u32 int_stat;
+	int ret;
+
+	if (op->data.dir == SPI_MEM_DATA_OUT)
+		hisi_sfc_v3xx_write_databuf(host, op->data.buf.out, op->data.nbytes);
+
+	ret = hisi_sfc_v3xx_start_bus(host, op, chip_select);
+	if (ret)
+		return ret;
+
 	ret = hisi_sfc_v3xx_wait_cmd_idle(host);
 	if (ret)
 		return ret;
@@ -265,7 +280,7 @@ static int hisi_sfc_v3xx_generic_exec_op(struct hisi_sfc_v3xx_host *host,
 	}
 
 	if (op->data.dir == SPI_MEM_DATA_IN)
-		hisi_sfc_v3xx_read_databuf(host, op->data.buf.in, len);
+		hisi_sfc_v3xx_read_databuf(host, op->data.buf.in, op->data.nbytes);
 
 	return 0;
 }