[PATCH v5 06/10] w1: replace dt detection by automatic detection

Kory Maincent kory.maincent at bootlin.com
Tue May 4 19:31:26 CEST 2021


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 at bootlin.com>
Reviewed-by: Maxime Ripard <maxime at cerno.tech>
---

Change since v2:
- drop the remove action of devicetree match in the W1 EEPROMs drivers.
- move the w1_device_register function to w1-uclass.
- update the w1_device_register function to be compatible with automatic
  detection and devicetree detection. I will not bind the device if it as
  been found in the devicetree.
- update the w1 device driver list to have only two parameters in the
  U_BOOT_W1_DEVICE function.

 drivers/w1-eeprom/ds24xxx.c          |  7 +++
 drivers/w1-eeprom/ds2502.c           |  6 +++
 drivers/w1-eeprom/w1-eeprom-uclass.c | 31 ------------
 drivers/w1/w1-uclass.c               | 76 +++++++++++++++++++++++++++-
 include/w1-eeprom.h                  |  2 -
 include/w1.h                         | 17 +++++++
 6 files changed, 104 insertions(+), 35 deletions(-)

diff --git a/drivers/w1-eeprom/ds24xxx.c b/drivers/w1-eeprom/ds24xxx.c
index d12fd5754e..4be378b43d 100644
--- a/drivers/w1-eeprom/ds24xxx.c
+++ b/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);
diff --git a/drivers/w1-eeprom/ds2502.c b/drivers/w1-eeprom/ds2502.c
index b3d68d7f05..a67f5edd0f 100644
--- a/drivers/w1-eeprom/ds2502.c
+++ b/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);
diff --git a/drivers/w1-eeprom/w1-eeprom-uclass.c b/drivers/w1-eeprom/w1-eeprom-uclass.c
index 97a9d43b03..7a02af3dd6 100644
--- a/drivers/w1-eeprom/w1-eeprom-uclass.c
+++ b/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);
diff --git a/drivers/w1/w1-uclass.c b/drivers/w1/w1-uclass.c
index 8bc6cb13f4..16aeeb6303 100644
--- a/drivers/w1/w1-uclass.c
+++ b/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 at free-electrons.com>
  * Eugen Hristev <eugen.hristev at microchip.com>
+ * Kory Maincent <kory.maincent at 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;
+	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);
 		}
 	}
 
diff --git a/include/w1-eeprom.h b/include/w1-eeprom.h
index 22337368b4..b3cf77a81e 100644
--- a/include/w1-eeprom.h
+++ b/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
diff --git a/include/w1.h b/include/w1.h
index 77f439e587..b18078ba15 100644
--- a/include/w1.h
+++ b/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;
 };
-- 
2.17.1



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