diff mbox

[media] dvb-frontends/cxd2841er: require STATE_ACTIVE_* for agc readout

Message ID 20170625100222.3222-1-d.scheller.oss@gmail.com (mailing list archive)
State New, archived
Headers show

Commit Message

Daniel Scheller June 25, 2017, 10:02 a.m. UTC 
From: Daniel Scheller <d.scheller@gmx.net>

When the demod driver puts the demod into sleep or shutdown state and it's
status is then polled e.g. via "dvb-fe-tool -m", i2c errors are printed
to the kernel log. If the last delsys was DVB-T/T2:

  cxd2841er: i2c wr failed=-5 addr=6c reg=00 len=1
  cxd2841er: i2c rd failed=-5 addr=6c reg=26

and if it was DVB-C:

  cxd2841er: i2c wr failed=-5 addr=6c reg=00 len=1
  cxd2841er: i2c rd failed=-5 addr=6c reg=49

This happens when read_status unconditionally calls into the
read_signal_strength() function which triggers the read_agc_gain_*()
functions, where these registered are polled.

This isn't a critical thing since when the demod is active again, no more
such errors are logged, however this might make users suspecting defects.

Fix this by requiring STATE_ACTIVE_* in priv->state. If it isn't in any
active state, additionally set the strength scale to NOT_AVAILABLE.

Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
---
V2/follow-up to https://patchwork.linuxtv.org/patch/42061/, changed as
requested. Tested, working fine (ie. no "false" i2c failures).

 drivers/media/dvb-frontends/cxd2841er.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Comments

Abylai Ospan June 29, 2017, 7:36 p.m. UTC | #1 
Acked-by: Abylay Ospan <aospan@netup.ru>

2017-06-25 6:02 GMT-04:00 Daniel Scheller <d.scheller.oss@gmail.com>:
> From: Daniel Scheller <d.scheller@gmx.net>
>
> When the demod driver puts the demod into sleep or shutdown state and it's
> status is then polled e.g. via "dvb-fe-tool -m", i2c errors are printed
> to the kernel log. If the last delsys was DVB-T/T2:
>
>   cxd2841er: i2c wr failed=-5 addr=6c reg=00 len=1
>   cxd2841er: i2c rd failed=-5 addr=6c reg=26
>
> and if it was DVB-C:
>
>   cxd2841er: i2c wr failed=-5 addr=6c reg=00 len=1
>   cxd2841er: i2c rd failed=-5 addr=6c reg=49
>
> This happens when read_status unconditionally calls into the
> read_signal_strength() function which triggers the read_agc_gain_*()
> functions, where these registered are polled.
>
> This isn't a critical thing since when the demod is active again, no more
> such errors are logged, however this might make users suspecting defects.
>
> Fix this by requiring STATE_ACTIVE_* in priv->state. If it isn't in any
> active state, additionally set the strength scale to NOT_AVAILABLE.
>
> Signed-off-by: Daniel Scheller <d.scheller@gmx.net>
> ---
> V2/follow-up to https://patchwork.linuxtv.org/patch/42061/, changed as
> requested. Tested, working fine (ie. no "false" i2c failures).
>
>  drivers/media/dvb-frontends/cxd2841er.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/media/dvb-frontends/cxd2841er.c b/drivers/media/dvb-frontends/cxd2841er.c
> index 08f67d60a7d9..12bff778c97f 100644
> --- a/drivers/media/dvb-frontends/cxd2841er.c
> +++ b/drivers/media/dvb-frontends/cxd2841er.c
> @@ -3279,7 +3279,10 @@ static int cxd2841er_get_frontend(struct dvb_frontend *fe,
>         else if (priv->state == STATE_ACTIVE_TC)
>                 cxd2841er_read_status_tc(fe, &status);
>
> -       cxd2841er_read_signal_strength(fe);
> +       if (priv->state == STATE_ACTIVE_TC || priv->state == STATE_ACTIVE_S)
> +               cxd2841er_read_signal_strength(fe);
> +       else
> +               p->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
>
>         if (status & FE_HAS_LOCK) {
>                 cxd2841er_read_snr(fe);
> --
> 2.13.0
>
diff mbox

Patch

diff --git a/drivers/media/dvb-frontends/cxd2841er.c b/drivers/media/dvb-frontends/cxd2841er.c
index 08f67d60a7d9..12bff778c97f 100644
--- a/drivers/media/dvb-frontends/cxd2841er.c
+++ b/drivers/media/dvb-frontends/cxd2841er.c
@@ -3279,7 +3279,10 @@  static int cxd2841er_get_frontend(struct dvb_frontend *fe,
 	else if (priv->state == STATE_ACTIVE_TC)
 		cxd2841er_read_status_tc(fe, &status);
 
-	cxd2841er_read_signal_strength(fe);
+	if (priv->state == STATE_ACTIVE_TC || priv->state == STATE_ACTIVE_S)
+		cxd2841er_read_signal_strength(fe);
+	else
+		p->strength.stat[0].scale = FE_SCALE_NOT_AVAILABLE;
 
 	if (status & FE_HAS_LOCK) {
 		cxd2841er_read_snr(fe);