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5bfbf65fcc
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] a1b673258f/drivers/media/pci/atomisp/atomisp_driver/atomisp_v4l2.c (L431-L514)
Fixes: 0f441fd70b ("media: atomisp: simplify the power down/up code")
Signed-off-by: Tsuchiya Yuto <kitakar@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Linux kernel
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