When comparing with intel-aero atomisp [1], it looks like punit_ddr_dvfs_enable() should take `false` as an argument on mrfld_power up case. Code from the intel-aero kernel [1]: int atomisp_mrfld_power_down(struct atomisp_device *isp) { [...] /*WA:Enable DVFS*/ if (IS_CHT) punit_ddr_dvfs_enable(true); int atomisp_mrfld_power_up(struct atomisp_device *isp) { [...] /*WA for PUNIT, if DVFS enabled, ISP timeout observed*/ if (IS_CHT) punit_ddr_dvfs_enable(false); This patch fixes the inverted argument as per the intel-aero code, as well as its comment. While here, fix space issues for comments in atomisp_mrfld_power(). Note that it does not seem to be possible to unify the up/down cases for punit_ddr_dvfs_enable(), i.e., we can't do something like the following: if (IS_CHT) punit_ddr_dvfs_enable(!enable); because according to the intel-aero code [1], the DVFS is disabled before "writing 0x0 to ISPSSPM0 bit[1:0]" and the DVFS is enabled after "writing 0x3 to ISPSSPM0 bit[1:0]". [1] https://github.com/intel-aero/linux-kernel/blob/a1b673258feb915268377275130c5c5df0eafc82/drivers/media/pci/atomisp/atomisp_driver/atomisp_v4l2.c#L431-L514 Fixes: 0f441fd70b1e ("media: atomisp: simplify the power down/up code") Signed-off-by: Tsuchiya Yuto <kitakar@xxxxxxxxx> --- drivers/staging/media/atomisp/pci/atomisp_v4l2.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/staging/media/atomisp/pci/atomisp_v4l2.c b/drivers/staging/media/atomisp/pci/atomisp_v4l2.c index 0511c454e769..f5362554638e 100644 --- a/drivers/staging/media/atomisp/pci/atomisp_v4l2.c +++ b/drivers/staging/media/atomisp/pci/atomisp_v4l2.c @@ -711,15 +711,15 @@ static int atomisp_mrfld_power(struct atomisp_device *isp, bool enable) dev_dbg(isp->dev, "IUNIT power-%s.\n", enable ? "on" : "off"); - /*WA:Enable DVFS*/ + /* WA for PUNIT, if DVFS enabled, ISP timeout observed */ if (IS_CHT && enable) - punit_ddr_dvfs_enable(true); + punit_ddr_dvfs_enable(false); /* * FIXME:WA for ECS28A, with this sleep, CTS * android.hardware.camera2.cts.CameraDeviceTest#testCameraDeviceAbort * PASS, no impact on other platforms - */ + */ if (IS_BYT && enable) msleep(10); @@ -727,7 +727,7 @@ static int atomisp_mrfld_power(struct atomisp_device *isp, bool enable) iosf_mbi_modify(BT_MBI_UNIT_PMC, MBI_REG_READ, MRFLD_ISPSSPM0, val, MRFLD_ISPSSPM0_ISPSSC_MASK); - /*WA:Enable DVFS*/ + /* WA:Enable DVFS */ if (IS_CHT && !enable) punit_ddr_dvfs_enable(true); -- 2.33.1