a67e1f0bd4
We can't use devm_platform_ioremap_resource_byname() to remap the
interrupt register that can be shared between
regulator-abb-{ivahd,dspeve,gpu} drivers instances.
The combined helper introduce a call to devm_request_mem_region() that
creates a new busy resource region on PRM_IRQSTATUS_MPU register
(0x4ae06010). The first devm_request_mem_region() call succeeds for
regulator-abb-ivahd but fails for the two other regulator-abb-dspeve
and regulator-abb-gpu.
# cat /proc/iomem | grep -i 4ae06
4ae06010-4ae06013 : 4ae07e34.regulator-abb-ivahd int-address
4ae06014-4ae06017 : 4ae07ddc.regulator-abb-mpu int-address
regulator-abb-dspeve and regulator-abb-gpu are missing due to
devm_request_mem_region() failure (EBUSY):
[ 1.326660] ti_abb 4ae07e30.regulator-abb-dspeve: can't request region for resource [mem 0x4ae06010-0x4ae06013]
[ 1.326660] ti_abb: probe of 4ae07e30.regulator-abb-dspeve failed with error -16
[ 1.327239] ti_abb 4ae07de4.regulator-abb-gpu: can't request region for resource [mem 0x4ae06010-0x4ae06013]
[ 1.327270] ti_abb: probe of 4ae07de4.regulator-abb-gpu failed with error -16
>From arm/boot/dts/dra7.dtsi:
The abb_mpu is the only instance using its own interrupt register:
(0x4ae06014) PRM_IRQSTATUS_MPU_2, ABB_MPU_DONE_ST (bit 7)
The other tree instances (abb_ivahd, abb_dspeve, abb_gpu) share
PRM_IRQSTATUS_MPU register (0x4ae06010) but use different bits
ABB_IVA_DONE_ST (bit 30), ABB_DSPEVE_DONE_ST( bit 29) and
ABB_GPU_DONE_ST (but 28).
The commit b36c6b1887ff ("regulator: ti-abb: Make use of the helper
function devm_ioremap related") overlooked the following comment
implicitly explaining why devm_ioremap() is used in this case:
/*
* We may have shared interrupt register offsets which are
* write-1-to-clear between domains ensuring exclusivity.
*/
Fixes and partially reverts commit b36c6b1887ff ("regulator: ti-abb:
Make use of the helper function devm_ioremap related").
Improve the existing comment to avoid further conversion to
devm_platform_ioremap_resource_byname().
Fixes: b36c6b1887ff ("regulator: ti-abb: Make use of the helper function devm_ioremap related")
Signed-off-by: Romain Naour <romain.naour@skf.com>
Reviewed-by: Yoann Congal <yoann.congal@smile.fr>
Link: https://msgid.link/r/20240123111456.739381-1-romain.naour@smile.fr
Signed-off-by: Mark Brown <broonie@kernel.org>
Linux kernel
============
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