[PATCH 1/4] i3c: mipi-i3c-hci: Allow only relevant INTR_STATUS bit updates
Jarkko Nikula
jarkko.nikula at linux.intel.com
Fri Feb 28 06:17:59 PST 2025
Since MIPI I3C HCI specification version v0.8 INTR_STATUS bits 9:0 are
reserved. Version v0.5 has bits 9 and 5:0 in use but not handled by the
current driver code and not needed in DMA transfers.
PIO transfers with v0.5 would require changes to both
core.c: i3c_hci_irq_handler() and pio.c: hci_pio_irq_handler() though.
For these reasons don't enable signal updates from INTR_STATUS bits 9:0.
This change is a no-op for specification versions v0.8 and beyond but
gets rid of "unexpected INTR_STATUS" errors if somebody (read me) wants
to run code on old v0.5 IP version.
Signed-off-by: Jarkko Nikula <jarkko.nikula at linux.intel.com>
---
drivers/i3c/master/mipi-i3c-hci/core.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
index a71226d7ca59..e139d7e4d252 100644
--- a/drivers/i3c/master/mipi-i3c-hci/core.c
+++ b/drivers/i3c/master/mipi-i3c-hci/core.c
@@ -699,9 +699,10 @@ static int i3c_hci_init(struct i3c_hci *hci)
if (ret)
return -ENXIO;
- /* Disable all interrupts and allow all signal updates */
+ /* Disable all interrupts */
reg_write(INTR_SIGNAL_ENABLE, 0x0);
- reg_write(INTR_STATUS_ENABLE, 0xffffffff);
+ /* Allow signal updates relevant to IP versions 0.8 and beyond */
+ reg_write(INTR_STATUS_ENABLE, GENMASK(31, 10));
/* Make sure our data ordering fits the host's */
regval = reg_read(HC_CONTROL);
--
2.47.2
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