[PATCH v2 0/2] mfd: rsmu: fixes and new IC support
From: Matthew Bystrin
Date: Wed Apr 29 2026 - 03:19:16 EST
Hi!
First patch fixes Renesas 8A34002 SPI driver.
In my setup 8A34002 is connected to VisionFive2 (via SPI or I2C). I've
discovered that upstream driver does not work:
[ 4.728771] 8a3400x-phc 8a3400x-phc.0.auto: 4.8.7, Id: 0x4002 HW Rev: 5 OTP Config Select: 0
[ 4.737389] 8a3400x-phc 8a3400x-phc.0.auto: requesting firmware 'idtcm.bin'
[ 4.744462] 8a3400x-phc 8a3400x-phc.0.auto: Direct firmware load for idtcm.bin failed with error -2
[ 4.753547] 8a3400x-phc 8a3400x-phc.0.auto: Failed at line 1273 in idtcm_load_firmware!
[ 4.761576] 8a3400x-phc 8a3400x-phc.0.auto: loading firmware failed with -2
[ 4.769411] 8a3400x-phc 8a3400x-phc.0.auto: No wait state: DPLL_SYS_STATE 0
[ 4.776374] 8a3400x-phc 8a3400x-phc.0.auto: Continuing while SYS APLL/DPLL is not locked
[ 4.785206] 8a3400x-phc 8a3400x-phc.0.auto: Unsupported MANUAL_REFERENCE: 0x00
[ 4.796930] 8a3400x-phc 8a3400x-phc.0.auto: PLL2 registered as ptp0
This being caused by a piece of code in rsmu_write_page_register() function:
if (reg < RSMU_CM_SCSR_BASE)
return 0;
All addresses in include/linux/mfd/idt8a340_reg.h are less than
RSMU_CM_SCSR_BASE so functions was returning early, before any modifications to
the page register. Valid read of versions - is just a coincidence, because
default value of the page register is zero.
There were 2 separate patch series which had to be merged in one time: mfd and
ptp. The latter have been merged, the former [1] have not. As result we've got a
broken driver.
This patch can be reverted later when the second part will be ready (of course
if it is planned to do so). Any comments, Min? I could support with testing.
Second patch just adds support for 8A34002, which is compatible with 8A34001. As
I can see there is no need to update bindings, everything is already being done.
Link [2] to v1.
Changes in v2:
- Fix page register issue in rsmu_i2c
- Add support for 8a34002 in rsmu_i2c
Link [1]: https://lore.kernel.org/netdev/LV3P220MB1202F8E2FCCFBA2519B4966EA0192@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
Link [2]: https://lore.kernel.org/netdev/20260421090710.395591-1-dev.mbstr@xxxxxxxxx/
Signed-off-by: Matthew Bystrin <dev.mbstr@xxxxxxxxx>
Matthew Bystrin (2):
mfd: rsmu: fix page register setup
mfd: rsmu: add 8a34002 support
drivers/mfd/rsmu_i2c.c | 8 +++-----
drivers/mfd/rsmu_spi.c | 7 +++----
2 files changed, 6 insertions(+), 9 deletions(-)
--
2.53.0