On 13/11/2024 03:49, Lifeng Zheng wrote: > With these codes, the value written in cpc register will be the result of > the OR operatiion on input value and prev_val. This will causes the value > to be wrong. > > Signed-off-by: Lifeng Zheng <zhenglifeng1@xxxxxxxxxx> > --- > drivers/acpi/cppc_acpi.c | 1 - > 1 file changed, 1 deletion(-) > > diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c > index 01192fd047a6..f69ef7cc0caf 100644 > --- a/drivers/acpi/cppc_acpi.c > +++ b/drivers/acpi/cppc_acpi.c > @@ -1146,7 +1146,6 @@ static int cpc_write(int cpu, struct cpc_register_resource *reg_res, u64 val) > return -EFAULT; > } > val = MASK_VAL_WRITE(reg, prev_val, val); > - val |= prev_val; Hi Lifeng, Indeed, MASK_VAL_WRITE() already takes care of ORing prev_val with the register mask. You can also add a Fixes: Fixes: 60949b7b8054 ("ACPI: CPPC: Fix MASK_VAL() usage") Thanks, Clément > } > > switch (size) {