w1: replace dt detection by automatic detection

This patch changes the functioning of the detection of w1 devices.
The old way was a comparison between detected w1 and the ones described in
the device tree. Now it will just look for the driver matching the family
id of the w1 detected.

The patch is inspired from Maxime Ripard code.

Signed-off-by: Kory Maincent <kory.maincent@bootlin.com>
Reviewed-by: Maxime Ripard <maxime@cerno.tech>

drivers/w1-eeprom/ds24xxx.c

@@ -53,3 +53,10 @@ U_BOOT_DRIVER(ds24xxx) = {
 	.ops		= &ds24xxx_ops,
 	.probe		= ds24xxx_probe,
 };
+
+u8 family_supported[] = {
+	W1_FAMILY_DS24B33,
+	W1_FAMILY_DS2431,
+};
+
+U_BOOT_W1_DEVICE(ds24xxx, family_supported);

drivers/w1-eeprom/ds2502.c

@@ -243,3 +243,9 @@ U_BOOT_DRIVER(ds2502) = {
 	.ops		= &ds2502_ops,
 	.probe		= ds2502_probe,
 };
+
+u8 family_supported[] = {
+	W1_FAMILY_DS2502,
+};
+
+U_BOOT_W1_DEVICE(ds2502, family_supported);

drivers/w1-eeprom/w1-eeprom-uclass.c

@@ -37,37 +37,6 @@ int w1_eeprom_read_buf(struct udevice *dev, unsigned int offset,
 	return ops->read_buf(dev, offset, buf, count);
 }
 
-int w1_eeprom_register_new_device(u64 id)
-{
-	u8 family = id & 0xff;
-	int ret;
-	struct udevice *dev;
-
-	for (ret = uclass_first_device(UCLASS_W1_EEPROM, &dev);
-	     !ret && dev;
-	     uclass_next_device(&dev)) {
-		if (ret || !dev) {
-			debug("cannot find w1 eeprom dev\n");
-			return ret;
-		}
-		if (dev_get_driver_data(dev) == family) {
-			struct w1_device *w1;
-
-			w1 = dev_get_parent_plat(dev);
-			if (w1->id) /* device already in use */
-				continue;
-			w1->id = id;
-			debug("%s: Match found: %s:%s %llx\n", __func__,
-			      dev->name, dev->driver->name, id);
-			return 0;
-		}
-	}
-
-	debug("%s: No matches found: error %d\n", __func__, ret);
-
-	return ret;
-}
-
 int w1_eeprom_get_id(struct udevice *dev, u64 *id)
 {
 	struct w1_device *w1 = dev_get_parent_plat(dev);

drivers/w1/w1-uclass.c

@@ -4,9 +4,11 @@
  * Copyright (c) 2015 Free Electrons
  * Copyright (c) 2015 NextThing Co.
  * Copyright (c) 2018 Microchip Technology, Inc.
+ * Copyright (c) 2021 Bootlin
  *
  * Maxime Ripard <maxime.ripard@free-electrons.com>
  * Eugen Hristev <eugen.hristev@microchip.com>
+ * Kory Maincent <kory.maincent@bootlin.com>
  *
  */
 
@@ -26,6 +28,76 @@ struct w1_bus {
 	u64	search_id;
 };
 
+int w1_bus_find_dev(const struct udevice *bus, u64 id, struct udevice
+**devp)
+{
+	struct udevice *dev;
+	u8 family = id & 0xff;
+	int ret;
+
+	for (ret = uclass_first_device(UCLASS_W1_EEPROM, &dev);
+		!ret && dev;
+		uclass_next_device(&dev)) {
+		if (ret || !dev) {
+			debug("cannot find w1 eeprom dev\n");
+			return -ENODEV;
+		}
+
+		if (dev_get_driver_data(dev) == family) {
+			*devp = dev;
+			return 0;
+		}
+	}
+
+	return -ENODEV;
+}
+
+int w1_register_new_device(u64 id, struct udevice *bus)
+{
+	u8 family = id & 0xff;
+	int n_ents, ret = 0;
+	struct udevice *dev;
+
+	struct w1_driver_entry *start, *entry;
+
+	start = ll_entry_start(struct w1_driver_entry, w1_driver_entry);
+	n_ents = ll_entry_count(struct w1_driver_entry, w1_driver_entry);
+
+	for (entry = start; entry != start + n_ents; entry++) {
+		const u8 *match_family;
+		const struct driver *drv;
+		struct w1_device *w1;
+
+		for (match_family = entry->family; match_family;
+		     match_family++) {
+			if (*match_family != family)
+				continue;
+
+			ret = w1_bus_find_dev(bus, id, &dev);
+
+			/* If nothing in the device tree, bind a device */
+			if (ret == -ENODEV) {
+				drv = entry->driver;
+				ret = device_bind(bus, drv, drv->name,
+						  NULL, ofnode_null(), &dev);
+				if (ret)
+					return ret;
+			}
+
+			device_probe(dev);
+
+			w1 = dev_get_parent_plat(dev);
+			w1->id = id;
+
+			return 0;
+		}
+	}
+
+	debug("%s: No matches found: error %d\n", __func__, ret);
+
+	return ret;
+}
+
 static int w1_enumerate(struct udevice *bus)
 {
 	const struct w1_ops *ops = device_get_ops(bus);
@@ -97,8 +169,8 @@ static int w1_enumerate(struct udevice *bus)
 			debug("%s: Detected new device 0x%llx (family 0x%x)\n",
 			      bus->name, rn, (u8)(rn & 0xff));
 
-			/* attempt to register as w1-eeprom device */
-			w1_eeprom_register_new_device(rn);
+			/* attempt to register as w1 device */
+			w1_register_new_device(rn, bus);
 		}
 	}
 

include/w1-eeprom.h

@@ -27,7 +27,5 @@ int w1_eeprom_read_buf(struct udevice *dev, unsigned int offset,
 
 int w1_eeprom_dm_init(void);
 
-int w1_eeprom_register_new_device(u64 id);
-
 int w1_eeprom_get_id(struct udevice *dev, u64 *id);
 #endif

include/w1.h

@@ -15,6 +15,23 @@ struct udevice;
 #define W1_FAMILY_DS2502	0x09
 #define W1_FAMILY_EEP_SANDBOX	0xfe
 
+struct w1_driver_entry {
+	struct driver	*driver;
+	u8		*family;
+};
+
+/* U_BOOT_W1_DEVICE() tells U-Boot to create a one-wire device.
+ *
+ * @__name: Device name (C identifier, not a string. E.g. gpio7_at_ff7e0000)
+ * @__driver: Driver name (C identifier, not a string. E.g. gpio7_at_ff7e0000)
+ * @__family: Family code number of the one-wire
+ */
+#define U_BOOT_W1_DEVICE(__name, __family)				\
+	ll_entry_declare(struct w1_driver_entry, __name, w1_driver_entry) = { \
+		.driver = llsym(struct driver, __name, driver),		\
+		.family = __family,					\
+	}
+
 struct w1_device {
 	u64	id;
 };