[PATCH v2 22/28] spi: s3c64xx: drop dependency on of_alias where possible

[Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>]

Remove the dependency on the OF alias for SoCs that use the same FIFO
size for all the instances of the SPI IP. The driver failed to probe if
an SPI alias was not provided, which is obviously wrong.

We now let the SPI core determine the SPI alias, either by getting the
alias ID, or by allocating a dynamic bus number when the alias is
absent.

Signed-off-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxx>
---
 drivers/spi/spi-s3c64xx.c | 61 ++++++++++++++++++++++++---------------
 1 file changed, 38 insertions(+), 23 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index b86eb0a77b60..7a99f6b02319 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -107,10 +107,9 @@
 
 #define S3C64XX_SPI_FBCLK_MASK			GENMASK(1, 0)
 
-#define FIFO_LVL_MASK(i) ((i)->port_conf->fifo_lvl_mask[i->port_id])
 #define S3C64XX_SPI_ST_TX_DONE(v, i) (((v) & \
 				(1 << (i)->port_conf->tx_st_done)) ? 1 : 0)
-#define FIFO_DEPTH(i) ((FIFO_LVL_MASK(i) >> 1) + 1)
+#define FIFO_DEPTH(x) (((x) >> 1) + 1)
 
 #define S3C64XX_SPI_POLLING_SIZE	32
 
@@ -197,7 +196,6 @@ struct s3c64xx_spi_driver_data {
 	struct s3c64xx_spi_dma_data	rx_dma;
 	struct s3c64xx_spi_dma_data	tx_dma;
 	const struct s3c64xx_spi_port_config	*port_conf;
-	unsigned int			port_id;
 	unsigned int			fifosize;
 };
 
@@ -1110,6 +1108,37 @@ static inline const struct s3c64xx_spi_port_config *s3c64xx_spi_get_port_config(
 	return (const struct s3c64xx_spi_port_config *)platform_get_device_id(pdev)->driver_data;
 }
 
+static int s3c64xx_spi_get_fifosize(const struct platform_device *pdev,
+				    struct s3c64xx_spi_driver_data *sdd)
+{
+	const struct s3c64xx_spi_port_config *port = sdd->port_conf;
+	const int *fifo_lvl_mask = port->fifo_lvl_mask;
+	struct device_node *np = pdev->dev.of_node;
+	int id;
+
+	if (!np) {
+		if (pdev->id < 0)
+			return dev_err_probe(&pdev->dev, -EINVAL,
+					     "Negative platform ID is not allowed\n");
+		id = pdev->id;
+		sdd->fifosize = FIFO_DEPTH(fifo_lvl_mask[id]);
+		return 0;
+	}
+
+	if (port->fifosize) {
+		sdd->fifosize = port->fifosize;
+		return 0;
+	}
+
+	id = of_alias_get_id(np, "spi");
+	if (id < 0)
+		return dev_err_probe(&pdev->dev, id,
+				     "Failed to get alias id\n");
+	sdd->fifosize = FIFO_DEPTH(fifo_lvl_mask[id]);
+
+	return 0;
+}
+
 static int s3c64xx_spi_probe(struct platform_device *pdev)
 {
 	struct resource	*mem_res;
@@ -1142,34 +1171,20 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
 
 	sdd = spi_controller_get_devdata(host);
 	sdd->port_conf = s3c64xx_spi_get_port_config(pdev);
+	ret = s3c64xx_spi_get_fifosize(pdev, sdd);
+	if (ret)
+		return ret;
+
 	sdd->host = host;
 	sdd->cntrlr_info = sci;
 	sdd->pdev = pdev;
-	if (pdev->dev.of_node) {
-		ret = of_alias_get_id(pdev->dev.of_node, "spi");
-		if (ret < 0)
-			return dev_err_probe(&pdev->dev, ret,
-					     "Failed to get alias id\n");
-		sdd->port_id = ret;
-	} else {
-		if (pdev->id < 0)
-			return dev_err_probe(&pdev->dev, -EINVAL,
-					     "Negative platform ID is not allowed\n");
-		sdd->port_id = pdev->id;
-	}
-
-	if (sdd->port_conf->fifosize)
-		sdd->fifosize = sdd->port_conf->fifosize;
-	else
-		sdd->fifosize = FIFO_DEPTH(sdd);
-
 	sdd->cur_bpw = 8;
 
 	sdd->tx_dma.direction = DMA_MEM_TO_DEV;
 	sdd->rx_dma.direction = DMA_DEV_TO_MEM;
 
 	host->dev.of_node = pdev->dev.of_node;
-	host->bus_num = sdd->port_id;
+	host->bus_num = -1;
 	host->setup = s3c64xx_spi_setup;
 	host->cleanup = s3c64xx_spi_cleanup;
 	host->prepare_transfer_hardware = s3c64xx_spi_prepare_transfer;
@@ -1250,7 +1265,7 @@ static int s3c64xx_spi_probe(struct platform_device *pdev)
 	}
 
 	dev_dbg(&pdev->dev, "Samsung SoC SPI Driver loaded for Bus SPI-%d with %d Targets attached\n",
-					sdd->port_id, host->num_chipselect);
+		host->bus_num, host->num_chipselect);
 	dev_dbg(&pdev->dev, "\tIOmem=[%pR]\tFIFO %dbytes\n",
 		mem_res, sdd->fifosize);
 
-- 
2.43.0.429.g432eaa2c6b-goog