This is a note to let you know that I've just added the patch titled clk: qcom: reset: Allow specifying custom reset delay to the 5.15-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: clk-qcom-reset-allow-specifying-custom-reset-delay.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 024faebe16f3c67ca7fc893a5f690df87f5542df Author: Stephan Gerhold <stephan.gerhold@xxxxxxxxxxxxxxx> Date: Wed Jul 6 15:41:29 2022 +0200 clk: qcom: reset: Allow specifying custom reset delay [ Upstream commit 2cb8a39b6781ea23accd1fa93b3ad000d0948aec ] The amount of time required between asserting and deasserting the reset signal can vary depending on the involved hardware component. Sometimes 1 us might not be enough and a larger delay is necessary to conform to the specifications. Usually this is worked around in the consuming drivers, by replacing reset_control_reset() with a sequence of reset_control_assert(), waiting for a custom delay, followed by reset_control_deassert(). However, in some cases the driver making use of the reset is generic and can be used with different reset controllers. In this case the reset time requirement is better handled directly by the reset controller driver. Make this possible by adding an "udelay" field to the qcom_reset_map that allows setting a different reset delay (in microseconds). Signed-off-by: Stephan Gerhold <stephan.gerhold@xxxxxxxxxxxxxxx> Signed-off-by: Bjorn Andersson <andersson@xxxxxxxxxx> Link: https://lore.kernel.org/r/20220706134132.3623415-4-stephan.gerhold@xxxxxxxxxxxxxxx Stable-dep-of: 349b5bed539b ("clk: qcom: ipq6018: fix networking resets") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/clk/qcom/reset.c b/drivers/clk/qcom/reset.c index 819d194be8f7b..2a16adb572d2b 100644 --- a/drivers/clk/qcom/reset.c +++ b/drivers/clk/qcom/reset.c @@ -13,8 +13,10 @@ static int qcom_reset(struct reset_controller_dev *rcdev, unsigned long id) { + struct qcom_reset_controller *rst = to_qcom_reset_controller(rcdev); + rcdev->ops->assert(rcdev, id); - udelay(1); + udelay(rst->reset_map[id].udelay ?: 1); /* use 1 us as default */ rcdev->ops->deassert(rcdev, id); return 0; } diff --git a/drivers/clk/qcom/reset.h b/drivers/clk/qcom/reset.h index 2a08b5e282c77..b8c113582072b 100644 --- a/drivers/clk/qcom/reset.h +++ b/drivers/clk/qcom/reset.h @@ -11,6 +11,7 @@ struct qcom_reset_map { unsigned int reg; u8 bit; + u8 udelay; }; struct regmap;