dm: spi: Move slave details to child platdata

At present we go through various contortions to store the SPI slave's chip
select in its private data. This only exists when the slave is active so
must be set up when it is probed. Until the device is probed we don't
actually know what chip select it will appear on.

However, now that we can support per-child platform data, we can use that
instead. This allows us to set up the chip select when the child is bound,
and avoid the messy contortions.

Unfortunately this is a fairly large change and it seems to be difficult to
break it down further.

Signed-off-by: Simon Glass <sjg@chromium.org>

2 files changed, 49 insertions, 43 deletions

diff --git a/drivers/spi/soft_spi.c b/drivers/spi/soft_spi.c
index 9f7d80e..6ae45f5 100644
--- a/drivers/spi/soft_spi.c
+++ b/drivers/spi/soft_spi.c
@@ -179,14 +179,6 @@ static int soft_spi_set_mode(struct udevice *dev, unsigned int mode)
 	return 0;
 }
 
-static int soft_spi_child_pre_probe(struct udevice *dev)
-{
-	struct spi_slave *slave = dev_get_parentdata(dev);
-
-	slave->dev = dev;
-	return spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, slave);
-}
-
 static const struct dm_spi_ops soft_spi_ops = {
 	.claim_bus	= soft_spi_claim_bus,
 	.release_bus	= soft_spi_release_bus,
@@ -241,5 +233,4 @@ U_BOOT_DRIVER(soft_spi) = {
 	.platdata_auto_alloc_size = sizeof(struct soft_spi_platdata),
 	.priv_auto_alloc_size = sizeof(struct soft_spi_priv),
 	.probe	= soft_spi_probe,
-	.child_pre_probe	= soft_spi_child_pre_probe,
 };
diff --git a/drivers/spi/spi-uclass.c b/drivers/spi/spi-uclass.c
index 2c134eb..63a6217 100644
--- a/drivers/spi/spi-uclass.c
+++ b/drivers/spi/spi-uclass.c
@@ -98,11 +98,21 @@ int spi_post_bind(struct udevice *dev)
 	return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
 }
 
-int spi_post_probe(struct udevice *dev)
+int spi_child_post_bind(struct udevice *dev)
 {
-	struct dm_spi_bus *spi = dev->uclass_priv;
+	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
 
-	spi->max_hz = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
+	if (dev->of_offset == -1)
+		return 0;
+
+	return spi_slave_ofdata_to_platdata(gd->fdt_blob, dev->of_offset, plat);
+}
+
+int spi_post_probe(struct udevice *bus)
+{
+	struct dm_spi_bus *spi = bus->uclass_priv;
+
+	spi->max_hz = fdtdec_get_int(gd->fdt_blob, bus->of_offset,
 				     "spi-max-frequency", 0);
 
 	return 0;
@@ -110,18 +120,29 @@ int spi_post_probe(struct udevice *dev)
 
 int spi_child_pre_probe(struct udevice *dev)
 {
+	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
 	struct spi_slave *slave = dev_get_parentdata(dev);
 
+	/*
+	 * This is needed because we pass struct spi_slave around the place
+	 * instead slave->dev (a struct udevice). So we have to have some
+	 * way to access the slave udevice given struct spi_slave. Once we
+	 * change the SPI API to use udevice instead of spi_slave, we can
+	 * drop this.
+	 */
 	slave->dev = dev;
 
+	slave->max_hz = plat->max_hz;
+	slave->mode = plat->mode;
+
 	return 0;
 }
 
 int spi_chip_select(struct udevice *dev)
 {
-	struct spi_slave *slave = dev_get_parentdata(dev);
+	struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
 
-	return slave ? slave->cs : -ENOENT;
+	return plat ? plat->cs : -ENOENT;
 }
 
 int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
@@ -130,17 +151,11 @@ int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
 
 	for (device_find_first_child(bus, &dev); dev;
 	     device_find_next_child(&dev)) {
-		struct spi_slave store;
-		struct spi_slave *slave = dev_get_parentdata(dev);
+		struct dm_spi_slave_platdata *plat;
 
-		if (!slave)  {
-			slave = &store;
-			spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset,
-					       slave);
-		}
-		debug("%s: slave=%p, cs=%d\n", __func__, slave,
-		      slave ? slave->cs : -1);
-		if (slave && slave->cs == cs) {
+		plat = dev_get_parent_platdata(dev);
+		debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
+		if (plat->cs == cs) {
 			*devp = dev;
 			return 0;
 		}
@@ -224,7 +239,6 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 		       struct udevice **busp, struct spi_slave **devp)
 {
 	struct udevice *bus, *dev;
-	struct spi_slave *slave;
 	bool created = false;
 	int ret;
 
@@ -241,11 +255,17 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 	 * SPI flash chip - we will bind to the correct driver.
 	 */
 	if (ret == -ENODEV && drv_name) {
+		struct dm_spi_slave_platdata *plat;
+
 		debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
 		      __func__, dev_name, busnum, cs, drv_name);
 		ret = device_bind_driver(bus, drv_name, dev_name, &dev);
 		if (ret)
 			return ret;
+		plat = dev_get_parent_platdata(dev);
+		plat->cs = cs;
+		plat->max_hz = speed;
+		plat->mode = mode;
 		created = true;
 	} else if (ret) {
 		printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
@@ -254,23 +274,13 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 	}
 
 	if (!device_active(dev)) {
-		slave = (struct spi_slave *)calloc(1,
-						   sizeof(struct spi_slave));
-		if (!slave) {
-			ret = -ENOMEM;
-			goto err;
-		}
+		struct spi_slave *slave;
 
-		ret = spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset,
-					     slave);
+		ret = device_probe(dev);
 		if (ret)
 			goto err;
-		slave->cs = cs;
+		slave = dev_get_parentdata(dev);
 		slave->dev = dev;
-		ret = device_probe_child(dev, slave);
-		free(slave);
-		if (ret)
-			goto err;
 	}
 
 	ret = spi_set_speed_mode(bus, speed, mode);
@@ -284,6 +294,8 @@ int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
 	return 0;
 
 err:
+	debug("%s: Error path, credted=%d, device '%s'\n", __func__,
+	      created, dev->name);
 	if (created) {
 		device_remove(dev);
 		device_unbind(dev);
@@ -330,13 +342,13 @@ void spi_free_slave(struct spi_slave *slave)
 	slave->dev = NULL;
 }
 
-int spi_ofdata_to_platdata(const void *blob, int node,
-			   struct spi_slave *spi)
+int spi_slave_ofdata_to_platdata(const void *blob, int node,
+				 struct dm_spi_slave_platdata *plat)
 {
 	int mode = 0;
 
-	spi->cs = fdtdec_get_int(blob, node, "reg", -1);
-	spi->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
+	plat->cs = fdtdec_get_int(blob, node, "reg", -1);
+	plat->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
 	if (fdtdec_get_bool(blob, node, "spi-cpol"))
 		mode |= SPI_CPOL;
 	if (fdtdec_get_bool(blob, node, "spi-cpha"))
@@ -345,7 +357,7 @@ int spi_ofdata_to_platdata(const void *blob, int node,
 		mode |= SPI_CS_HIGH;
 	if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
 		mode |= SPI_PREAMBLE;
-	spi->mode = mode;
+	plat->mode = mode;
 
 	return 0;
 }
@@ -359,6 +371,9 @@ UCLASS_DRIVER(spi) = {
 	.child_pre_probe = spi_child_pre_probe,
 	.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
 	.per_child_auto_alloc_size = sizeof(struct spi_slave),
+	.per_child_platdata_auto_alloc_size =
+			sizeof(struct dm_spi_slave_platdata),
+	.child_post_bind = spi_child_post_bind,
 };
 
 UCLASS_DRIVER(spi_generic) = {