[PATCH 11/12] i3c: mipi-i3c-hci: Resume controller explicitly

Jarkko Nikula jarkko.nikula at linux.intel.com
Wed Sep 20 22:57:03 PDT 2023


On an HW I'm using in enabling work the RESUME bit is not set in the
HC_CONTROLLER register when Host Controller goes to halt state. Value 1
should mean controller is suspended when reading and writing 1 resumes it.

Because of this erratic behaviour plain HC_CONTROL read and write back
won't resume the controller. Therefore do it by setting the RESUME bit
explicitly.

Signed-off-by: Jarkko Nikula <jarkko.nikula at linux.intel.com>
---
 drivers/i3c/master/mipi-i3c-hci/core.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/i3c/master/mipi-i3c-hci/core.c b/drivers/i3c/master/mipi-i3c-hci/core.c
index d7fe8e62820a..1ae56a5699c6 100644
--- a/drivers/i3c/master/mipi-i3c-hci/core.c
+++ b/drivers/i3c/master/mipi-i3c-hci/core.c
@@ -174,8 +174,7 @@ static void i3c_hci_bus_cleanup(struct i3c_master_controller *m)
 
 void mipi_i3c_hci_resume(struct i3c_hci *hci)
 {
-	/* the HC_CONTROL_RESUME bit is R/W1C so just read and write back */
-	reg_write(HC_CONTROL, reg_read(HC_CONTROL));
+	reg_set(HC_CONTROL, HC_CONTROL_RESUME);
 }
 
 /* located here rather than pio.c because needed bits are in core reg space */
-- 
2.40.1




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