While trying to reproduce -EBUSY errors that our lab was getting in suspend/resume testing, I ended up finding a whole pile of problems with the Qualcomm GENI serial driver. I've posted a fix for the -EBUSY issue separately [1]. This series is fixing all of the Qualcomm GENI problems that I found. As far as I can tell most of the problems have been in the Qualcomm GENI serial driver since inception, but it can be noted that the behavior got worse with the new kfifo changes. Previously when the OS took data out of the circular queue we'd just spit stale data onto the serial port. Now we'll hard lockup. :-P I've tried to break this series up as much as possible to make it easier to understand but the final patch is still a lot of change at once. Hopefully it's OK. [1] https://lore.kernel.org/r/20240530084841.v2.1.I2395e66cf70c6e67d774c56943825c289b9c13e4@changeid Changes in v2: - soc: qcom: geni-se: Add GP_LENGTH/IRQ_EN_SET/IRQ_EN_CLEAR registers - serial: qcom-geni: Fix the timeout in qcom_geni_serial_poll_bit() - serial: qcom-geni: Fix arg types for qcom_geni_serial_poll_bit() - serial: qcom-geni: Introduce qcom_geni_serial_poll_bitfield() - serial: qcom-geni: Just set the watermark level once - Totally rework / rename patch to handle suspend while active xfer - serial: qcom-geni: Rework TX in FIFO mode to fix hangs/lockups Douglas Anderson (7): soc: qcom: geni-se: Add GP_LENGTH/IRQ_EN_SET/IRQ_EN_CLEAR registers serial: qcom-geni: Fix the timeout in qcom_geni_serial_poll_bit() serial: qcom-geni: Fix arg types for qcom_geni_serial_poll_bit() serial: qcom-geni: Introduce qcom_geni_serial_poll_bitfield() serial: qcom-geni: Just set the watermark level once serial: qcom-geni: Fix suspend while active UART xfer serial: qcom-geni: Rework TX in FIFO mode to fix hangs/lockups drivers/tty/serial/qcom_geni_serial.c | 316 ++++++++++++++++---------- include/linux/soc/qcom/geni-se.h | 6 + 2 files changed, 203 insertions(+), 119 deletions(-) -- 2.45.1.288.g0e0cd299f1-goog
