Add two functions which can find a child device by uclass or by name. The first is useful with Multi-Function-Devices (MFDs) to find one of a particular type. The second is useful when only the name is known.
Signed-off-by: Simon Glass sjg@chromium.org ---
Changes in v2: None
drivers/core/device.c | 34 ++++++++++++++++++++++++++++++++++ include/dm/device.h | 25 +++++++++++++++++++++++++ test/dm/test-fdt.c | 27 +++++++++++++++++++++++++++ 3 files changed, 86 insertions(+)
diff --git a/drivers/core/device.c b/drivers/core/device.c index 47a697f3e5c..836bcadced5 100644 --- a/drivers/core/device.c +++ b/drivers/core/device.c @@ -699,6 +699,40 @@ int device_find_first_inactive_child(struct udevice *parent, return -ENODEV; }
+int device_find_first_child_by_uclass(struct udevice *parent, + enum uclass_id uclass_id, + struct udevice **devp) +{ + struct udevice *dev; + + *devp = NULL; + list_for_each_entry(dev, &parent->child_head, sibling_node) { + if (device_get_uclass_id(dev) == uclass_id) { + *devp = dev; + return 0; + } + } + + return -ENODEV; +} + +int device_find_child_by_name(struct udevice *parent, const char *name, + struct udevice **devp) +{ + struct udevice *dev; + + *devp = NULL; + + list_for_each_entry(dev, &parent->child_head, sibling_node) { + if (!strcmp(dev->name, name)) { + *devp = dev; + return 0; + } + } + + return -ENODEV; +} + struct udevice *dev_get_parent(const struct udevice *child) { return child->parent; diff --git a/include/dm/device.h b/include/dm/device.h index 847934425bb..27a6d7b9fdb 100644 --- a/include/dm/device.h +++ b/include/dm/device.h @@ -525,6 +525,8 @@ int device_find_next_child(struct udevice **devp); * This is used to locate an existing child of a device which is of a given * uclass. * + * The device is NOT probed + * * @parent: Parent device to search * @uclass_id: Uclass to look for * @devp: Returns device found, if any @@ -534,6 +536,29 @@ int device_find_first_inactive_child(struct udevice *parent, enum uclass_id uclass_id, struct udevice **devp);
+/** + * device_find_first_child_by_uclass() - Find the first child of a device in uc + * + * @parent: Parent device to search + * @uclass_id: Uclass to look for + * @devp: Returns first child device in that uclass, if any + * @return 0 if found, else -ENODEV + */ +int device_find_first_child_by_uclass(struct udevice *parent, + enum uclass_id uclass_id, + struct udevice **devp); + +/** + * device_find_child_by_name() - Find a child by device name + * + * @parent: Parent device to search + * @name: Name to look for + * @devp: Returns device found, if any + * @return 0 if found, else -ENODEV + */ +int device_find_child_by_name(struct udevice *parent, const char *name, + struct udevice **devp); + /** * device_has_children() - check if a device has any children * diff --git a/test/dm/test-fdt.c b/test/dm/test-fdt.c index b70e3fa18ac..0fbd9be765a 100644 --- a/test/dm/test-fdt.c +++ b/test/dm/test-fdt.c @@ -631,3 +631,30 @@ static int dm_test_fdt_phandle(struct unit_test_state *uts) return 0; } DM_TEST(dm_test_fdt_phandle, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT); + +/* Test device_find_first_child_by_uclass() */ +static int dm_test_first_child(struct unit_test_state *uts) +{ + struct udevice *i2c, *dev, *dev2; + + ut_assertok(uclass_first_device_err(UCLASS_I2C, &i2c)); + ut_assertok(device_find_first_child_by_uclass(i2c, UCLASS_RTC, &dev)); + ut_asserteq_str("rtc@43", dev->name); + ut_assertok(device_find_child_by_name(i2c, "rtc@43", &dev2)); + ut_asserteq_ptr(dev, dev2); + ut_assertok(device_find_child_by_name(i2c, "rtc@61", &dev2)); + ut_asserteq_str("rtc@61", dev2->name); + + ut_assertok(device_find_first_child_by_uclass(i2c, UCLASS_I2C_EEPROM, + &dev)); + ut_asserteq_str("eeprom@2c", dev->name); + ut_assertok(device_find_child_by_name(i2c, "eeprom@2c", &dev2)); + ut_asserteq_ptr(dev, dev2); + + ut_asserteq(-ENODEV, device_find_first_child_by_uclass(i2c, + UCLASS_VIDEO, &dev)); + ut_asserteq(-ENODEV, device_find_child_by_name(i2c, "missing", &dev)); + + return 0; +} +DM_TEST(dm_test_first_child, DM_TESTF_SCAN_PDATA | DM_TESTF_SCAN_FDT);