I am trying to get the DS, but
https://www.nxp.com/acrobat_download/literature/9397/75015931.pdf is a
dead links now.

Anyone have access to the datasheet?

Thanks!

On Fri, 3 May 2024 at 13:55, Dan Carpenter [off-list ref] wrote:

On Fri, May 03, 2024 at 11:27:58AM +0100, Mauro Carvalho Chehab wrote:

quoted

Em Mon, 29 Apr 2024 15:05:05 +0000
Ricardo Ribalda [off-list ref] escreveu:

quoted

We do not expect the sample_freq to be over 613MHz.

Found by cocci:
drivers/media/dvb-frontends/tda10048.c:345:1-7: WARNING: do_div() does a 64-by-32 division, please consider using div64_u64 instead.

Signed-off-by: Ricardo Ribalda <redacted>
---
 drivers/media/dvb-frontends/tda10048.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/media/dvb-frontends/tda10048.c b/drivers/media/dvb-frontends/tda10048.c
index 3e725cdcc66b..1886f733dbbf 100644
--- a/drivers/media/dvb-frontends/tda10048.c
+++ b/drivers/media/dvb-frontends/tda10048.c

@@ -328,7 +328,8 @@ static int tda10048_set_wref(struct dvb_frontend *fe, u32 sample_freq_hz,
                         u32 bw)
 {
    struct tda10048_state *state = fe->demodulator_priv;
-   u64 t, z;
+   u32 z;
+   u64 t;

    dprintk(1, "%s()\n", __func__);

@@ -341,6 +342,7 @@ static int tda10048_set_wref(struct dvb_frontend *fe, u32 sample_freq_hz,
    /* t *= 2147483648 on 32bit platforms */
    t *= (2048 * 1024);
    t *= 1024;
+   /* Sample frequency is under 613MHz */

Are you sure about that? Some DVB devices have very high frequency
clocks, specially if they're also used for satellite, so I can't
be sure by just looking at the driver's code.

Also, we had already a bunch of regressions with "fixes" like this
that actually broke frontend drivers.

This patch preserves the existing behavior. The sample_freq_hz variable
is a u32 so, in the original code, z couldn't have been more than
U32_MAX even though it was declared as a u64.

It's possible that the original code was wrong.  We have seen that in
other places in this patchset.  Adding a note about the datasheet is
also a good idea.

regards,
dan carpenter

-- 
Ricardo Ribalda

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