dmaengine: idxd: Register dsa_bus_type before registering idxd sub-drivers

[ Upstream commit 88928addeec577386e8c83b48b5bc24d28ba97fd ]

idxd sub-drivers belong to bus dsa_bus_type. Thus, dsa_bus_type must be
registered in dsa bus init before idxd drivers can be registered.

But the order is wrong when both idxd and idxd_bus are builtin drivers.
In this case, idxd driver is compiled and linked before idxd_bus driver.
Since the initcall order is determined by the link order, idxd sub-drivers
are registered in idxd initcall before dsa_bus_type is registered
in idxd_bus initcall. idxd initcall fails:

[   21.562803] calling  idxd_init_module+0x0/0x110 @ 1
[   21.570761] Driver 'idxd' was unable to register with bus_type 'dsa' because the bus was not initialized.
[   21.586475] initcall idxd_init_module+0x0/0x110 returned -22 after 15717 usecs
[   21.597178] calling  dsa_bus_init+0x0/0x20 @ 1

To fix the issue, compile and link idxd_bus driver before idxd driver
to ensure the right registration order.

Fixes: d9e5481fca ("dmaengine: dsa: move dsa_bus_type out of idxd driver to standalone")
Reported-by: Michael Prinke <michael.prinke@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Lijun Pan <lijun.pan@intel.com>
Tested-by: Lijun Pan <lijun.pan@intel.com>
Link: https://lore.kernel.org/r/20230924162232.1409454-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drivers/dma/idxd/Makefile

@@ -1,12 +1,12 @@
 ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=IDXD
 
+obj-$(CONFIG_INTEL_IDXD_BUS) += idxd_bus.o
+idxd_bus-y := bus.o
+
 obj-$(CONFIG_INTEL_IDXD) += idxd.o
 idxd-y := init.o irq.o device.o sysfs.o submit.o dma.o cdev.o
 
 idxd-$(CONFIG_INTEL_IDXD_PERFMON) += perfmon.o
 
-obj-$(CONFIG_INTEL_IDXD_BUS) += idxd_bus.o
-idxd_bus-y := bus.o
-
 obj-$(CONFIG_INTEL_IDXD_COMPAT) += idxd_compat.o
 idxd_compat-y := compat.o