This is a note to let you know that I've just added the patch titled serial: qcom_geni_serial: To correct QUP Version detection logic to the 5.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: serial-qcom_geni_serial-to-correct-qup-version-detection-logic.patch and it can be found in the queue-5.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From c9ca43d42ed8d5fd635d327a664ed1d8579eb2af Mon Sep 17 00:00:00 2001 From: Paras Sharma <parashar@xxxxxxxxxxxxxx> Date: Wed, 30 Sep 2020 11:35:26 +0530 Subject: serial: qcom_geni_serial: To correct QUP Version detection logic From: Paras Sharma <parashar@xxxxxxxxxxxxxx> commit c9ca43d42ed8d5fd635d327a664ed1d8579eb2af upstream. For QUP IP versions 2.5 and above the oversampling rate is halved from 32 to 16. Commit ce734600545f ("tty: serial: qcom_geni_serial: Update the oversampling rate") is pushed to handle this scenario. But the existing logic is failing to classify QUP Version 3.0 into the correct group ( 2.5 and above). As result Serial Engine clocks are not configured properly for baud rate and garbage data is sampled to FIFOs from the line. So, fix the logic to detect QUP with versions 2.5 and above. Fixes: ce734600545f ("tty: serial: qcom_geni_serial: Update the oversampling rate") Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Paras Sharma <parashar@xxxxxxxxxxxxxx> Reviewed-by: Akash Asthana <akashast@xxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1601445926-23673-1-git-send-email-parashar@xxxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/qcom_geni_serial.c | 2 +- include/linux/qcom-geni-se.h | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) --- a/drivers/tty/serial/qcom_geni_serial.c +++ b/drivers/tty/serial/qcom_geni_serial.c @@ -954,7 +954,7 @@ static void qcom_geni_serial_set_termios sampling_rate = UART_OVERSAMPLING; /* Sampling rate is halved for IP versions >= 2.5 */ ver = geni_se_get_qup_hw_version(&port->se); - if (GENI_SE_VERSION_MAJOR(ver) >= 2 && GENI_SE_VERSION_MINOR(ver) >= 5) + if (ver >= QUP_SE_VERSION_2_5) sampling_rate /= 2; clk_rate = get_clk_div_rate(baud, sampling_rate, &clk_div); --- a/include/linux/qcom-geni-se.h +++ b/include/linux/qcom-geni-se.h @@ -229,6 +229,9 @@ struct geni_se { #define GENI_SE_VERSION_MINOR(ver) ((ver & HW_VER_MINOR_MASK) >> HW_VER_MINOR_SHFT) #define GENI_SE_VERSION_STEP(ver) (ver & HW_VER_STEP_MASK) +/* QUP SE VERSION value for major number 2 and minor number 5 */ +#define QUP_SE_VERSION_2_5 0x20050000 + #if IS_ENABLED(CONFIG_QCOM_GENI_SE) u32 geni_se_get_qup_hw_version(struct geni_se *se); Patches currently in stable-queue which might be from parashar@xxxxxxxxxxxxxx are queue-5.8/serial-qcom_geni_serial-to-correct-qup-version-detection-logic.patch