Currently, driver binding stops once it encounters the first compatible driver that doesn't refuse to bind. However, there are cases where a single node will need to be handled by multiple driver classes. For those cases we provide a configurable option to continue to bind after the first driver has been found.
The first use cases for this are from the DM conversion of the sunxi (Allwinner) architecture: * pinctrl (UCLASS_PINCTRL) and gpio (UCLASS_GPIO) drivers need to bind against a single node * clock (UCLASS_CLK) and reset (UCLASS_RESET) drivers also need to bind against a single node
Signed-off-by: Philipp Tomsich philipp.tomsich@theobroma-systems.com --- drivers/core/Kconfig | 14 ++++++++++++++ drivers/core/lists.c | 12 +++++++++++- 2 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/drivers/core/Kconfig b/drivers/core/Kconfig index 8749561..913101c 100644 --- a/drivers/core/Kconfig +++ b/drivers/core/Kconfig @@ -31,6 +31,20 @@ config DM_WARN This will cause dm_warn() to be compiled out - it will do nothing when called.
+config DM_ALLOW_MULTIPLE_DRIVERS + bool "Allow multiple drivers to bind for one node" + depends on DM + default n + help + The driver model in U-Boot originally did not allow multiple + drivers to bind for a single device node. + + If enabled, multiple drivers can now bind for a single node + by using the same compatible string for matching: lists_bind_fdt() + will assume that binding multiple drivers is desirable, if the + caller does not request the pointer to the udevice structure to + be returned (i.e. if devp is NULL). + config DM_DEVICE_REMOVE bool "Support device removal" depends on DM diff --git a/drivers/core/lists.c b/drivers/core/lists.c index 23b6ba7..52efe69 100644 --- a/drivers/core/lists.c +++ b/drivers/core/lists.c @@ -166,7 +166,11 @@ int lists_bind_fdt(struct udevice *parent, const void *blob, int offset, dm_dbg(" - attempt to match compatible string '%s'\n", compat);
- for (entry = driver; entry != driver + n_ents; entry++) { + entry = driver; +#if defined(CONFIG_DM_ALLOW_MULTIPLE_DRIVERS) + allow_more_matches: +#endif + for (; entry != driver + n_ents; entry++) { ret = driver_check_compatible(entry->of_match, &id, compat); if (!ret) @@ -190,6 +194,12 @@ int lists_bind_fdt(struct udevice *parent, const void *blob, int offset, found = true; if (devp) *devp = dev; +#if defined(CONFIG_DM_ALLOW_MULTIPLE_DRIVERS) + else { + entry++; + goto allow_more_matches; + } +#endif } break; }