[PATCH 2/3] Input: applespi: Fix occasional crc errors under load.

From: Ronald Tschalär
Date: Wed Feb 17 2021 - 14:19:20 EST


For some reason, when the system is under heavy CPU load, the read
following the write sometimes occurs unusually quickly, resulting in
the read data not being quite ready and hence a bad packet getting read.
Adding another delay after reading the status message appears to fix
this.

Signed-off-by: Ronald Tschalär <ronald@xxxxxxxxxxxxx>
---
drivers/input/keyboard/applespi.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/input/keyboard/applespi.c b/drivers/input/keyboard/applespi.c
index 8494bf610fd70..f0a0067c48ff6 100644
--- a/drivers/input/keyboard/applespi.c
+++ b/drivers/input/keyboard/applespi.c
@@ -749,6 +749,8 @@ static void applespi_async_write_complete(void *context)
applespi->tx_status,
APPLESPI_STATUS_SIZE);

+ udelay(SPI_RW_CHG_DELAY_US);
+
if (!applespi_check_write_status(applespi, applespi->wr_m.status)) {
/*
* If we got an error, we presumably won't get the expected
--
2.26.2