Re: [PATCH 03/17] i3c: renesas: Restore STDBR and EXTBR registers on resume
From: Claudiu Beznea
Date: Thu May 28 2026 - 04:39:32 EST
Hi, Frank,
On 5/22/26 22:10, Frank Li wrote:
On Fri, May 22, 2026 at 01:18:01PM +0300, Claudiu Beznea wrote:
From: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
The Renesas RZ/G3S supports a power saving state where power to the most
SoC componentes (including I3C) is lost.
The STDBR and EXTBR are configured in initialization phase though the
struct i3c_master_controller_ops::bus_init. Set them on resume function
as well to keep the same state of the controller after a suspend with
power loss and a similar initialization sequence as in bus_init.
Fixes: e7218986319b ("i3c: renesas: Add suspend/resume support")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@xxxxxxxxxxxxxx>
---
drivers/i3c/master/renesas-i3c.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/i3c/master/renesas-i3c.c b/drivers/i3c/master/renesas-i3c.c
index 1917549cf6d5..6c23f956ad2a 100644
--- a/drivers/i3c/master/renesas-i3c.c
+++ b/drivers/i3c/master/renesas-i3c.c
@@ -260,6 +260,7 @@ struct renesas_i3c {
u32 dyn_addr;
u32 i2c_STDBR;
u32 i3c_STDBR;
+ u32 extbr;
can you keep consisent with above 2 register, use upcase EXTBR,
Using upper case for this will mislead the compiler. There is already a macro defined for EXTBR:
#define EXTBR 0x78
Defining this member as:
u32 EXTBR;
will make the compiler try to replace the EXTBR in "i3c->EXTBR" at preprocessing time:
CC [M] drivers/i3c/master/renesas-i3c.o
../drivers/i3c/master/renesas-i3c.c:65:17: error: expected identifier or ‘(’ before numeric constant
65 | #define EXTBR 0x78
| ^~~~
../drivers/i3c/master/renesas-i3c.c:263:6: note: in expansion of macro ‘EXTBR’
263 | u32 EXTBR;
| ^~~~~
../drivers/i3c/master/renesas-i3c.c: In function ‘renesas_i3c_bus_init’:
../drivers/i3c/master/renesas-i3c.c:65:17: error: expected identifier before numeric constant
65 | #define EXTBR 0x78
| ^~~~
../drivers/i3c/master/renesas-i3c.c:611:7: note: in expansion of macro ‘EXTBR’
611 | i3c->EXTBR = EXTBR_EBRLO(od_low_ticks) | EXTBR_EBRHO(od_high_ticks) |
| ^~~~~
../drivers/i3c/master/renesas-i3c.c:65:17: error: expected identifier before numeric constant
65 | #define EXTBR 0x78
| ^~~~
../drivers/i3c/master/renesas-i3c.c:613:40: note: in expansion of macro ‘EXTBR’
613 | renesas_writel(i3c->regs, EXTBR, i3c->EXTBR);
| ^~~~~
../drivers/i3c/master/renesas-i3c.c: In function ‘renesas_i3c_resume_noirq’:
../drivers/i3c/master/renesas-i3c.c:65:17: error: expected identifier before numeric constant
65 | #define EXTBR 0x78
| ^~~~
../drivers/i3c/master/renesas-i3c.c:1451:40: note: in expansion of macro ‘EXTBR’
1451 | renesas_writel(i3c->regs, EXTBR, i3c->EXTBR);
| ^~~~~
The register contains both i3c and i2c specific fields. I'm not sure using i2c_i3c_EXTBR is the best way to go forward for this or just keeping it as is.
--
Thank you,
Claudiu