From: "J. Neuschäfer" <j...@posteo.net>
Historically, devicetree nodes representing the Freescale Enhanced
Local Bus Controller (eLBC) have compatible strings such as:
compatible = "fsl,mpc8313-elbc", "fsl,elbc", "simple-bus";
The "simple-bus" string causes the bus to be populated, and the memory
devices contained within it to be discovered. The eLBC bus (as
represented in device trees) differs from a simple-bus in a few ways,
though:
- Addresses are not simple/linear: The first cell of an address is a
chip select, the second is an linear address within the space thus
selected. Representing 1,0 as 100000000, for example, would decrease
readability[1].
- It is expected that the devices on a simple-bus "can be accessed
directly without additional configuration required"[2], but the eLBC
needs some configuration.
To accommodate devicetrees that declare an eLBC without "simple-bus",
explicitly populate the bus in the eLBC driver.
[1]: dtc makes such a suggestion opon encountering an eLBC
[2]: Quoting the Devicetree Specification Release v0.3
Signed-off-by: J. Neuschäfer <j...@posteo.net>
---
arch/powerpc/sysdev/fsl_lbc.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/arch/powerpc/sysdev/fsl_lbc.c b/arch/powerpc/sysdev/fsl_lbc.c
index
217cea150987df1e1b5c6dbf9e9a1607dd5ce49b..2007ced997fcf0c7059e5b780893b530764dc8b2
100644
--- a/arch/powerpc/sysdev/fsl_lbc.c
+++ b/arch/powerpc/sysdev/fsl_lbc.c
@@ -20,6 +20,7 @@
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
+#include <linux/of_platform.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/platform_device.h>
@@ -336,7 +337,7 @@ static int fsl_lbc_ctrl_probe(struct platform_device *dev)
/* Enable interrupts for any detected events */
out_be32(&fsl_lbc_ctrl_dev->regs->lteir, LTEIR_ENABLE);
- return 0;
+ return devm_of_platform_populate(&dev->dev);
err1:
free_irq(fsl_lbc_ctrl_dev->irq[0], fsl_lbc_ctrl_dev);
---
base-commit: 7ccde445dddcca030cd6ed66974bb80915ad9dd5
change-id: 20250209-localbus-94a6ebb04c12
Best regards,
--
J. Neuschäfer <j...@posteo.net>
