diff mbox series

ARM: dts: am33xx: add aliases for mmc interfaces

Message ID 20210128155644.6553-1-mans@mansr.com (mailing list archive)
State New
Headers show
Series ARM: dts: am33xx: add aliases for mmc interfaces | expand

Commit Message

Måns Rullgård Jan. 28, 2021, 3:56 p.m. UTC
Without DT aliases, the numbering of mmc interfaces is unpredictable.
Adding them makes it possible to refer to devices consistently.  The
popular suggestion to use UUIDs obviously doesn't work with a blank
device fresh from the factory.

See fa2d0aa96941 "mmc: core: Allow setting slot index via device tree
alias" for more discussion.

Signed-off-by: Mans Rullgard <mans@mansr.com>
---
 arch/arm/boot/dts/am33xx.dtsi | 3 +++
 1 file changed, 3 insertions(+)

Comments

Tony Lindgren Feb. 4, 2021, 6:45 a.m. UTC | #1
* Måns Rullgård <mans@mansr.com> [210129 11:40]:
> Tony Lindgren <tony@atomide.com> writes:
> 
> > * Mans Rullgard <mans@mansr.com> [210128 18:09]:
> >> Without DT aliases, the numbering of mmc interfaces is unpredictable.
> >> Adding them makes it possible to refer to devices consistently.  The
> >> popular suggestion to use UUIDs obviously doesn't work with a blank
> >> device fresh from the factory.
> >> 
> >> See fa2d0aa96941 "mmc: core: Allow setting slot index via device tree
> >> alias" for more discussion.
> >
> > Sounds good to me, but will wait a few days before applying to make sure
> > this is still what we have agreed on :)
> 
> If it helps the decision, my existing systems fail to boot without
> something like this due to the eMMC moving from /dev/mmcblk1 to mmcblk0,
> at least sometimes.  I guess the kernel cares deeply about not breaking
> userspace, except when it doesn't give a damn.
> 
> I've been fighting this problem in various forms for the last 10 years
> or so, and I was hoping it would finally be over.

Yes this issue has been bugging folks for long time. Applying into fixes
thanks.

Tony
diff mbox series

Patch

diff --git a/arch/arm/boot/dts/am33xx.dtsi b/arch/arm/boot/dts/am33xx.dtsi
index 4c2298024137..f09a61cac2dc 100644
--- a/arch/arm/boot/dts/am33xx.dtsi
+++ b/arch/arm/boot/dts/am33xx.dtsi
@@ -40,6 +40,9 @@  aliases {
 		ethernet1 = &cpsw_emac1;
 		spi0 = &spi0;
 		spi1 = &spi1;
+		mmc0 = &mmc1;
+		mmc1 = &mmc2;
+		mmc2 = &mmc3;
 	};
 
 	cpus {