[PATCH v2 3/6] dm: core: Support multiple drivers with same compatibles

[Markus Schneider-Pargmann (TI.com)]

Currently once a driver matched the compatible string of a device, other
drivers are ignored. If the first matching driver returns -ENODEV, no
other possibly matching drivers are iterated with that compatible of the
device. Instead the next compatible in the list of compatibles is
selected, assuming only one driver matches one compatible at a time.

To be able to use the bind function to return -ENODEV and continue
matching other drivers with the same compatible, move the for loop a bit
to continue the for loop after -ENODEV was returned. The loop had to be
adjusted a bit to still support the 'drv' argument properly. Some
simplifications where done as well.

This is required for ti-musb-host and ti-musb-peripheral which both
match on the same device but differ based on the dr_mode DT property.
Depending on this property, the driver is either UCLASS_USB or
UCLASS_USB_GADGET_GENERIc. By checking the DT property in the bind
function and returning -ENODEV the other driver can probe instead.

Signed-off-by: Markus Schneider-Pargmann (TI.com) <msp at baylibre.com>
---
 drivers/core/lists.c | 65 ++++++++++++++++++++++++++--------------------------
 1 file changed, 33 insertions(+), 32 deletions(-)

diff --git a/drivers/core/lists.c b/drivers/core/lists.c
index 9d1ca38212ee7f53b8894f964f096611c8ec20a5..3d9f9bc93954efdd624dddb1833f3a855c3c28de 100644
--- a/drivers/core/lists.c
+++ b/drivers/core/lists.c
@@ -235,50 +235,51 @@ int lists_bind_fdt(struct udevice *parent, ofnode node, struct udevice **devp,
 		log_debug("   - attempt to match compatible string '%s'\n",
 			  compat);
 
-		id = NULL;
 		for (entry = driver; entry != driver + n_ents; entry++) {
+			/* Search for drivers with matching drv or existing of_match */
 			if (drv) {
 				if (drv != entry)
 					continue;
-				if (!entry->of_match)
-					break;
+			} else if (!entry->of_match) {
+				continue;
 			}
-			ret = driver_check_compatible(entry->of_match, &id,
-						      compat);
-			if (!ret)
-				break;
-		}
-		if (entry == driver + n_ents)
-			continue;
 
-		if (pre_reloc_only) {
-			if (!ofnode_pre_reloc(node) &&
-			    !(entry->flags & DM_FLAG_PRE_RELOC)) {
-				log_debug("Skipping device pre-relocation\n");
-				return 0;
+			id = NULL;
+			if (entry->of_match) {
+				ret = driver_check_compatible(entry->of_match, &id,
+							      compat);
+				if (ret)
+					continue;
+				log_debug("   - found match at driver '%s' for '%s'\n",
+					  entry->name, id->compatible);
+			}
+
+			if (pre_reloc_only) {
+				if (!ofnode_pre_reloc(node) &&
+				    !(entry->flags & DM_FLAG_PRE_RELOC)) {
+					log_debug("   - Skipping device pre-relocation\n");
+					return 0;
+				}
+			}
+
+			ret = device_bind_with_driver_data(parent, entry, name,
+							   id ? id->data : 0, node,
+							   &dev);
+			if (!drv && ret == -ENODEV) {
+				log_debug("   - Driver '%s' refuses to bind\n", entry->name);
+				continue;
+			}
+			if (ret) {
+				dm_warn("Error binding driver '%s': %d\n", entry->name,
+					ret);
+				return log_msg_ret("bind", ret);
 			}
-		}
 
-		if (entry->of_match)
-			log_debug("   - found match at driver '%s' for '%s'\n",
-				  entry->name, id->compatible);
-		ret = device_bind_with_driver_data(parent, entry, name,
-						   id ? id->data : 0, node,
-						   &dev);
-		if (ret == -ENODEV) {
-			log_debug("Driver '%s' refuses to bind\n", entry->name);
-			continue;
-		}
-		if (ret) {
-			dm_warn("Error binding driver '%s': %d\n", entry->name,
-				ret);
-			return log_msg_ret("bind", ret);
-		} else {
 			if (devp)
 				*devp = dev;
+
 			return 0;
 		}
-		break;
 	}
 
 	if (ret != -ENODEV)

-- 
2.51.0