spi: atmel: Remove platform data support

This driver is now only used through the device tree. Simplify code
by explicitly depend on device tree.
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://lore.kernel.org/r/20191017141846.7523-6-gregory.clement@bootlin.comSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/Kconfig

@@ -80,6 +80,7 @@ config SPI_ARMADA_3700
 config SPI_ATMEL
 	tristate "Atmel SPI Controller"
 	depends on ARCH_AT91 || COMPILE_TEST
+	depends on OF
 	help
 	  This selects a driver for the Atmel SPI Controller, present on
 	  many AT91 ARM chips.

drivers/spi/spi-atmel.c

@@ -1500,7 +1500,7 @@ static int atmel_spi_probe(struct platform_device *pdev)
 	master->bits_per_word_mask = SPI_BPW_RANGE_MASK(8, 16);
 	master->dev.of_node = pdev->dev.of_node;
 	master->bus_num = pdev->id;
-	master->num_chipselect = master->dev.of_node ? 0 : 4;
+	master->num_chipselect = 4;
 	master->setup = atmel_spi_setup;
 	master->flags = (SPI_MASTER_MUST_RX | SPI_MASTER_MUST_TX);
 	master->transfer_one_message = atmel_spi_transfer_one_message;
@@ -1528,16 +1528,6 @@ static int atmel_spi_probe(struct platform_device *pdev)
 
 	atmel_get_caps(as);
 
-	/*
-	 * If there are chip selects in the device tree, those will be
-	 * discovered by the SPI core when registering the SPI master
-	 * and assigned to each SPI device.
-	 */
-	if (atmel_spi_is_v2(as) &&
-	    pdev->dev.of_node &&
-	    !of_get_property(pdev->dev.of_node, "cs-gpios", NULL))
-		master->num_chipselect = 4;
-
 	as->use_dma = false;
 	as->use_pdc = false;
 	if (as->caps.has_dma_support) {
@@ -1745,20 +1735,18 @@ static const struct dev_pm_ops atmel_spi_pm_ops = {
 #define ATMEL_SPI_PM_OPS	NULL
 #endif
 
-#if defined(CONFIG_OF)
 static const struct of_device_id atmel_spi_dt_ids[] = {
 	{ .compatible = "atmel,at91rm9200-spi" },
 	{ /* sentinel */ }
 };
 
 MODULE_DEVICE_TABLE(of, atmel_spi_dt_ids);
-#endif
 
 static struct platform_driver atmel_spi_driver = {
 	.driver		= {
 		.name	= "atmel_spi",
 		.pm	= ATMEL_SPI_PM_OPS,
-		.of_match_table	= of_match_ptr(atmel_spi_dt_ids),
+		.of_match_table	= atmel_spi_dt_ids,
 	},
 	.probe		= atmel_spi_probe,
 	.remove		= atmel_spi_remove,