From: Wang Qing <[email protected]>
do_div() does a 64-by-32 division.
When the divisor is u64, do_div() truncates it to 32 bits, this means it
can test non-zero and be truncated to zero for division.
fix do_div.cocci warning:
do_div() does a 64-by-32 division, please consider using div64_u64 instead.
Signed-off-by: Wang Qing <[email protected]>
---
drivers/media/dvb-frontends/tda10048.c | 2 +-
drivers/media/dvb-frontends/tda18271c2dd.c | 4 ++--
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/media/dvb-frontends/tda10048.c b/drivers/media/dvb-frontends/tda10048.c
index d1d206e..1ce2e67
--- a/drivers/media/dvb-frontends/tda10048.c
+++ b/drivers/media/dvb-frontends/tda10048.c
@@ -344,7 +344,7 @@ static int tda10048_set_wref(struct dvb_frontend *fe, u32 sample_freq_hz,
z = 7 * sample_freq_hz;
do_div(t, z);
t += 5;
- do_div(t, 10);
+ div64_u64(t, 10);
tda10048_writereg(state, TDA10048_TIME_WREF_LSB, (u8)t);
tda10048_writereg(state, TDA10048_TIME_WREF_MID1, (u8)(t >> 8));
diff --git a/drivers/media/dvb-frontends/tda18271c2dd.c b/drivers/media/dvb-frontends/tda18271c2dd.c
index a3483448..fd92878
--- a/drivers/media/dvb-frontends/tda18271c2dd.c
+++ b/drivers/media/dvb-frontends/tda18271c2dd.c
@@ -328,7 +328,7 @@ static int CalcMainPLL(struct tda_state *state, u32 freq)
OscFreq = (u64) freq * (u64) Div;
OscFreq *= (u64) 16384;
- do_div(OscFreq, (u64)16000000);
+ do_div(OscFreq, 16000000);
MainDiv = OscFreq;
state->m_Regs[MPD] = PostDiv & 0x77;
@@ -352,7 +352,7 @@ static int CalcCalPLL(struct tda_state *state, u32 freq)
OscFreq = (u64)freq * (u64)Div;
/* CalDiv = u32( OscFreq * 16384 / 16000000 ); */
OscFreq *= (u64)16384;
- do_div(OscFreq, (u64)16000000);
+ do_div(OscFreq, 16000000);
CalDiv = OscFreq;
state->m_Regs[CPD] = PostDiv;
--
2.7.4
On 09/02/2022 09:38, Qing Wang wrote:
> From: Wang Qing <[email protected]>
>
> do_div() does a 64-by-32 division.
> When the divisor is u64, do_div() truncates it to 32 bits, this means it
> can test non-zero and be truncated to zero for division.
>
> fix do_div.cocci warning:
> do_div() does a 64-by-32 division, please consider using div64_u64 instead.
>
> Signed-off-by: Wang Qing <[email protected]>
> ---
> drivers/media/dvb-frontends/tda10048.c | 2 +-
> drivers/media/dvb-frontends/tda18271c2dd.c | 4 ++--
> 2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/media/dvb-frontends/tda10048.c b/drivers/media/dvb-frontends/tda10048.c
> index d1d206e..1ce2e67
> --- a/drivers/media/dvb-frontends/tda10048.c
> +++ b/drivers/media/dvb-frontends/tda10048.c
> @@ -344,7 +344,7 @@ static int tda10048_set_wref(struct dvb_frontend *fe, u32 sample_freq_hz,
> z = 7 * sample_freq_hz;
> do_div(t, z);
> t += 5;
> - do_div(t, 10);
> + div64_u64(t, 10);
This makes no sense, I think you intended to convert the previous do_div(t, z).
>
> tda10048_writereg(state, TDA10048_TIME_WREF_LSB, (u8)t);
> tda10048_writereg(state, TDA10048_TIME_WREF_MID1, (u8)(t >> 8));
> diff --git a/drivers/media/dvb-frontends/tda18271c2dd.c b/drivers/media/dvb-frontends/tda18271c2dd.c
> index a3483448..fd92878
> --- a/drivers/media/dvb-frontends/tda18271c2dd.c
> +++ b/drivers/media/dvb-frontends/tda18271c2dd.c
> @@ -328,7 +328,7 @@ static int CalcMainPLL(struct tda_state *state, u32 freq)
>
> OscFreq = (u64) freq * (u64) Div;
> OscFreq *= (u64) 16384;
> - do_div(OscFreq, (u64)16000000);
> + do_div(OscFreq, 16000000);
> MainDiv = OscFreq;
>
> state->m_Regs[MPD] = PostDiv & 0x77;
> @@ -352,7 +352,7 @@ static int CalcCalPLL(struct tda_state *state, u32 freq)
> OscFreq = (u64)freq * (u64)Div;
> /* CalDiv = u32( OscFreq * 16384 / 16000000 ); */
> OscFreq *= (u64)16384;
> - do_div(OscFreq, (u64)16000000);
> + do_div(OscFreq, 16000000);
> CalDiv = OscFreq;
>
> state->m_Regs[CPD] = PostDiv;
The changes here do not match with the subject line of this patch.
I think it is best to split this into two patches, one for each source.
Regards,
Hans