From: Mauro Carvalho Chehab <mchehab@redhat.com>
To: Michael Krufky <mkrufky@linuxtv.org>
Cc: Antti Palosaari <crope@iki.fi>,
Linux Media Mailing List <linux-media@vger.kernel.org>
Subject: Re: [PATCH] tda18271-common: hold the I2C adapter during write transfers
Date: Sun, 7 Oct 2012 09:42:20 -0300 [thread overview]
Message-ID: <20121007094220.53666e94@redhat.com> (raw)
In-Reply-To: <CAOcJUbxC3vP53Lfoca+Qy5Zab9tHgj1oQ=GrOtTRNLe99Cue8A@mail.gmail.com>
Em Sat, 29 Sep 2012 15:20:23 -0400
Michael Krufky <mkrufky@linuxtv.org> escreveu:
> On Fri, Sep 28, 2012 at 2:56 PM, Michael Krufky <mkrufky@linuxtv.org> wrote:
> > On Fri, Sep 28, 2012 at 2:31 PM, Antti Palosaari <crope@iki.fi> wrote:
> >> Hello,
> >> Did not fix the issue. Problem remains same. With the sleep + that patch it
> >> works still.
> >>
> >> On 09/28/2012 06:04 PM, Mauro Carvalho Chehab wrote:
> >>>
> >>> The tda18271 datasheet says:
> >>>
> >>> "The image rejection calibration and RF tracking filter
> >>> calibration must be launched exactly as described in the
> >>> flowchart, otherwise bad calibration or even blocking of the
> >>> TDA18211HD can result making it impossible to communicate
> >>> via the I2C-bus."
> >>>
> >>> (yeah, tda18271 refers there to tda18211 - likely a typo at their
> >>> datasheets)
> >>
> >>
> >> tda18211 is just same than tda18271 but without a analog.
> >>
> >>> That likely explains why sometimes tda18271 stops answering. That
> >>> is now happening more often on designs with drx-k chips, as the
> >>> firmware is now loaded asyncrousnly there.
> >>>
> >>> While the above text doesn't explicitly tell that the I2C bus
> >>> couldn't be used by other devices during such initialization,
> >>> that seems to be a requirement there.
> >>>
> >>> So, let's explicitly use the I2C lock there, avoiding I2C bus
> >>> share during those critical moments.
> >>>
> >>> Compile-tested only. Please test.
> >>>
> >>> Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
> >>> ---
> >>> drivers/media/tuners/tda18271-common.c | 104
> >>> ++++++++++++++++++++++-----------
> >>> 1 file changed, 71 insertions(+), 33 deletions(-)
> >>>
> >>> diff --git a/drivers/media/tuners/tda18271-common.c
> >>> b/drivers/media/tuners/tda18271-common.c
> >>> index 221171e..18c77af 100644
> >>> --- a/drivers/media/tuners/tda18271-common.c
> >>> +++ b/drivers/media/tuners/tda18271-common.c
> >>> @@ -187,7 +187,8 @@ int tda18271_read_extended(struct dvb_frontend *fe)
> >>> return (ret == 2 ? 0 : ret);
> >>> }
> >>>
> >>> -int tda18271_write_regs(struct dvb_frontend *fe, int idx, int len)
> >>> +static int __tda18271_write_regs(struct dvb_frontend *fe, int idx, int
> >>> len,
> >>> + bool lock_i2c)
> >>> {
> >>> struct tda18271_priv *priv = fe->tuner_priv;
> >>> unsigned char *regs = priv->tda18271_regs;
> >>> @@ -198,7 +199,6 @@ int tda18271_write_regs(struct dvb_frontend *fe, int
> >>> idx, int len)
> >>>
> >>> BUG_ON((len == 0) || (idx + len > sizeof(buf)));
> >>>
> >>> -
> >>> switch (priv->small_i2c) {
> >>> case TDA18271_03_BYTE_CHUNK_INIT:
> >>> max = 3;
> >>> @@ -214,7 +214,19 @@ int tda18271_write_regs(struct dvb_frontend *fe, int
> >>> idx, int len)
> >>> max = 39;
> >>> }
> >>>
> >>> - tda18271_i2c_gate_ctrl(fe, 1);
> >>> +
> >>> + /*
> >>> + * If lock_i2c is true, it will take the I2C bus for tda18271
> >>> private
> >>> + * usage during the entire write ops, as otherwise, bad things
> >>> could
> >>> + * happen.
> >>> + * During device init, several write operations will happen. So,
> >>> + * tda18271_init_regs controls the I2C lock directly,
> >>> + * disabling lock_i2c here.
> >>> + */
> >>> + if (lock_i2c) {
> >>> + tda18271_i2c_gate_ctrl(fe, 1);
> >>> + i2c_lock_adapter(priv->i2c_props.adap);
> >>> + }
> >>> while (len) {
> >>> if (max > len)
> >>> max = len;
> >>> @@ -226,14 +238,17 @@ int tda18271_write_regs(struct dvb_frontend *fe, int
> >>> idx, int len)
> >>> msg.len = max + 1;
> >>>
> >>> /* write registers */
> >>> - ret = i2c_transfer(priv->i2c_props.adap, &msg, 1);
> >>> + ret = __i2c_transfer(priv->i2c_props.adap, &msg, 1);
> >>> if (ret != 1)
> >>> break;
> >>>
> >>> idx += max;
> >>> len -= max;
> >>> }
> >>> - tda18271_i2c_gate_ctrl(fe, 0);
> >>> + if (lock_i2c) {
> >>> + i2c_unlock_adapter(priv->i2c_props.adap);
> >>> + tda18271_i2c_gate_ctrl(fe, 0);
> >>> + }
> >>>
> >>> if (ret != 1)
> >>> tda_err("ERROR: idx = 0x%x, len = %d, "
> >>> @@ -242,10 +257,16 @@ int tda18271_write_regs(struct dvb_frontend *fe, int
> >>> idx, int len)
> >>> return (ret == 1 ? 0 : ret);
> >>> }
> >>>
> >>> +int tda18271_write_regs(struct dvb_frontend *fe, int idx, int len)
> >>> +{
> >>> + return __tda18271_write_regs(fe, idx, len, true);
> >>> +}
> >>> +
> >>>
> >>> /*---------------------------------------------------------------------*/
> >>>
> >>> -int tda18271_charge_pump_source(struct dvb_frontend *fe,
> >>> - enum tda18271_pll pll, int force)
> >>> +static int __tda18271_charge_pump_source(struct dvb_frontend *fe,
> >>> + enum tda18271_pll pll, int force,
> >>> + bool lock_i2c)
> >>> {
> >>> struct tda18271_priv *priv = fe->tuner_priv;
> >>> unsigned char *regs = priv->tda18271_regs;
> >>> @@ -255,9 +276,16 @@ int tda18271_charge_pump_source(struct dvb_frontend
> >>> *fe,
> >>> regs[r_cp] &= ~0x20;
> >>> regs[r_cp] |= ((force & 1) << 5);
> >>>
> >>> - return tda18271_write_regs(fe, r_cp, 1);
> >>> + return __tda18271_write_regs(fe, r_cp, 1, lock_i2c);
> >>> +}
> >>> +
> >>> +int tda18271_charge_pump_source(struct dvb_frontend *fe,
> >>> + enum tda18271_pll pll, int force)
> >>> +{
> >>> + return __tda18271_charge_pump_source(fe, pll, force, true);
> >>> }
> >>>
> >>> +
> >>> int tda18271_init_regs(struct dvb_frontend *fe)
> >>> {
> >>> struct tda18271_priv *priv = fe->tuner_priv;
> >>> @@ -267,6 +295,13 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> i2c_adapter_id(priv->i2c_props.adap),
> >>> priv->i2c_props.addr);
> >>>
> >>> + /*
> >>> + * Don't let any other I2C transfer to happen at adapter during
> >>> init,
> >>> + * as those could cause bad things
> >>> + */
> >>> + tda18271_i2c_gate_ctrl(fe, 1);
> >>> + i2c_lock_adapter(priv->i2c_props.adap);
> >>> +
> >>> /* initialize registers */
> >>> switch (priv->id) {
> >>> case TDA18271HDC1:
> >>> @@ -352,28 +387,28 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> regs[R_EB22] = 0x48;
> >>> regs[R_EB23] = 0xb0;
> >>>
> >>> - tda18271_write_regs(fe, 0x00, TDA18271_NUM_REGS);
> >>> + __tda18271_write_regs(fe, 0x00, TDA18271_NUM_REGS, false);
> >>>
> >>> /* setup agc1 gain */
> >>> regs[R_EB17] = 0x00;
> >>> - tda18271_write_regs(fe, R_EB17, 1);
> >>> + __tda18271_write_regs(fe, R_EB17, 1, false);
> >>> regs[R_EB17] = 0x03;
> >>> - tda18271_write_regs(fe, R_EB17, 1);
> >>> + __tda18271_write_regs(fe, R_EB17, 1, false);
> >>> regs[R_EB17] = 0x43;
> >>> - tda18271_write_regs(fe, R_EB17, 1);
> >>> + __tda18271_write_regs(fe, R_EB17, 1, false);
> >>> regs[R_EB17] = 0x4c;
> >>> - tda18271_write_regs(fe, R_EB17, 1);
> >>> + __tda18271_write_regs(fe, R_EB17, 1, false);
> >>>
> >>> /* setup agc2 gain */
> >>> if ((priv->id) == TDA18271HDC1) {
> >>> regs[R_EB20] = 0xa0;
> >>> - tda18271_write_regs(fe, R_EB20, 1);
> >>> + __tda18271_write_regs(fe, R_EB20, 1, false);
> >>> regs[R_EB20] = 0xa7;
> >>> - tda18271_write_regs(fe, R_EB20, 1);
> >>> + __tda18271_write_regs(fe, R_EB20, 1, false);
> >>> regs[R_EB20] = 0xe7;
> >>> - tda18271_write_regs(fe, R_EB20, 1);
> >>> + __tda18271_write_regs(fe, R_EB20, 1, false);
> >>> regs[R_EB20] = 0xec;
> >>> - tda18271_write_regs(fe, R_EB20, 1);
> >>> + __tda18271_write_regs(fe, R_EB20, 1, false);
> >>> }
> >>>
> >>> /* image rejection calibration */
> >>> @@ -391,21 +426,21 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> regs[R_MD2] = 0x08;
> >>> regs[R_MD3] = 0x00;
> >>>
> >>> - tda18271_write_regs(fe, R_EP3, 11);
> >>> + __tda18271_write_regs(fe, R_EP3, 11, false);
> >>>
> >>> if ((priv->id) == TDA18271HDC2) {
> >>> /* main pll cp source on */
> >>> - tda18271_charge_pump_source(fe, TDA18271_MAIN_PLL, 1);
> >>> + __tda18271_charge_pump_source(fe, TDA18271_MAIN_PLL, 1,
> >>> false);
> >>> msleep(1);
> >>>
> >>> /* main pll cp source off */
> >>> - tda18271_charge_pump_source(fe, TDA18271_MAIN_PLL, 0);
> >>> + __tda18271_charge_pump_source(fe, TDA18271_MAIN_PLL, 0,
> >>> false);
> >>> }
> >>>
> >>> msleep(5); /* pll locking */
> >>>
> >>> /* launch detector */
> >>> - tda18271_write_regs(fe, R_EP1, 1);
> >>> + __tda18271_write_regs(fe, R_EP1, 1, false);
> >>> msleep(5); /* wanted low measurement */
> >>>
> >>> regs[R_EP5] = 0x85;
> >>> @@ -413,11 +448,11 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> regs[R_CD1] = 0x66;
> >>> regs[R_CD2] = 0x70;
> >>>
> >>> - tda18271_write_regs(fe, R_EP3, 7);
> >>> + __tda18271_write_regs(fe, R_EP3, 7, false);
> >>> msleep(5); /* pll locking */
> >>>
> >>> /* launch optimization algorithm */
> >>> - tda18271_write_regs(fe, R_EP2, 1);
> >>> + __tda18271_write_regs(fe, R_EP2, 1, false);
> >>> msleep(30); /* image low optimization completion */
> >>>
> >>> /* mid-band */
> >>> @@ -428,11 +463,11 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> regs[R_MD1] = 0x73;
> >>> regs[R_MD2] = 0x1a;
> >>>
> >>> - tda18271_write_regs(fe, R_EP3, 11);
> >>> + __tda18271_write_regs(fe, R_EP3, 11, false);
> >>> msleep(5); /* pll locking */
> >>>
> >>> /* launch detector */
> >>> - tda18271_write_regs(fe, R_EP1, 1);
> >>> + __tda18271_write_regs(fe, R_EP1, 1, false);
> >>> msleep(5); /* wanted mid measurement */
> >>>
> >>> regs[R_EP5] = 0x86;
> >>> @@ -440,11 +475,11 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> regs[R_CD1] = 0x66;
> >>> regs[R_CD2] = 0xa0;
> >>>
> >>> - tda18271_write_regs(fe, R_EP3, 7);
> >>> + __tda18271_write_regs(fe, R_EP3, 7, false);
> >>> msleep(5); /* pll locking */
> >>>
> >>> /* launch optimization algorithm */
> >>> - tda18271_write_regs(fe, R_EP2, 1);
> >>> + __tda18271_write_regs(fe, R_EP2, 1, false);
> >>> msleep(30); /* image mid optimization completion */
> >>>
> >>> /* high-band */
> >>> @@ -456,30 +491,33 @@ int tda18271_init_regs(struct dvb_frontend *fe)
> >>> regs[R_MD1] = 0x71;
> >>> regs[R_MD2] = 0xcd;
> >>>
> >>> - tda18271_write_regs(fe, R_EP3, 11);
> >>> + __tda18271_write_regs(fe, R_EP3, 11, false);
> >>> msleep(5); /* pll locking */
> >>>
> >>> /* launch detector */
> >>> - tda18271_write_regs(fe, R_EP1, 1);
> >>> + __tda18271_write_regs(fe, R_EP1, 1, false);
> >>> msleep(5); /* wanted high measurement */
> >>>
> >>> regs[R_EP5] = 0x87;
> >>> regs[R_CD1] = 0x65;
> >>> regs[R_CD2] = 0x50;
> >>>
> >>> - tda18271_write_regs(fe, R_EP3, 7);
> >>> + __tda18271_write_regs(fe, R_EP3, 7, false);
> >>> msleep(5); /* pll locking */
> >>>
> >>> /* launch optimization algorithm */
> >>> - tda18271_write_regs(fe, R_EP2, 1);
> >>> + __tda18271_write_regs(fe, R_EP2, 1, false);
> >>> msleep(30); /* image high optimization completion */
> >>>
> >>> /* return to normal mode */
> >>> regs[R_EP4] = 0x64;
> >>> - tda18271_write_regs(fe, R_EP4, 1);
> >>> + __tda18271_write_regs(fe, R_EP4, 1, false);
> >>>
> >>> /* synchronize */
> >>> - tda18271_write_regs(fe, R_EP1, 1);
> >>> + __tda18271_write_regs(fe, R_EP1, 1, false);
> >>> +
> >>> + i2c_unlock_adapter(priv->i2c_props.adap);
> >>> + tda18271_i2c_gate_ctrl(fe, 0);
> >>>
> >>> return 0;
> >>> }
> >>>
> >>
> >>
> >> --
> >> http://palosaari.fi/
> >
> > I have to NACK this particular patch -- I saw Mauro's email about the
> > locked i2c -- it's a great idea. In fact, it is the original use case
> > for adding this functionality into i2c, I just never got around to
> > implementing it in the tda18271 driver. However, it shouldnt be
> > around *all* i2c transactions -- it should only lock the i2c bus
> > during the *critical* section. Please wait for me to send a new patch
> > for testing. I'll try to get to it before the end of the weekend.
> > (hopefully tonight or tomorrow morning)
>
> On further inspection of the patch, I see that it *does* attempt to
> only lock the i2c bus during the initialization of the device. The
> patch could be optimized a bit to specifically only lock the bus
> during the critical section of the initialization itself, but that is
> no reason to block this patch.
Yesh, I took the care of not locking all transactions, locking just the
init code.
> So, I retract my NACK.
Ok, I'll apply it then.
> If we decide
> to merge this, then we can optimize it afterwards.
Yeah, for sure optimization there is very welcome.
>
> -Mike
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
Regards,
Mauro
next prev parent reply other threads:[~2012-10-07 12:42 UTC|newest]
Thread overview: 36+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-22 19:59 tda18271 driver power consumption Antti Palosaari
2012-07-24 21:55 ` Michael Krufky
2012-07-24 22:12 ` Antti Palosaari
2012-07-24 22:17 ` Michael Krufky
2012-07-25 0:15 ` Michael Krufky
2012-07-25 0:43 ` Antti Palosaari
2012-07-26 3:18 ` Michael Krufky
2012-07-26 12:48 ` Michael Krufky
2012-08-06 13:30 ` Antti Palosaari
[not found] ` <20120927161940.0f673e2e@redhat.com>
2012-09-27 19:59 ` Antti Palosaari
2012-09-27 21:20 ` Michael Krufky
2012-09-27 21:38 ` Antti Palosaari
2012-09-27 21:58 ` Michael Krufky
2012-09-27 22:26 ` Antti Palosaari
2012-09-27 22:43 ` Michael Krufky
2012-09-27 22:46 ` Antti Palosaari
2012-09-27 22:55 ` Michael Krufky
2012-09-27 23:05 ` Antti Palosaari
[not found] ` <20120928084337.1db94b8c@redhat.com>
2012-09-28 15:04 ` [PATCH] tda18271-common: hold the I2C adapter during write transfers Mauro Carvalho Chehab
2012-09-28 18:31 ` Antti Palosaari
2012-09-28 18:56 ` Michael Krufky
2012-09-29 19:20 ` Michael Krufky
2012-10-07 12:42 ` Mauro Carvalho Chehab [this message]
2012-10-07 13:18 ` Michael Krufky
2012-10-01 10:42 ` Mauro Carvalho Chehab
2012-10-01 11:31 ` Antti Palosaari
2012-10-01 12:36 ` Mauro Carvalho Chehab
2012-09-28 16:19 ` tda18271 driver power consumption Antti Palosaari
2012-08-06 18:19 ` Antti Palosaari
2012-08-06 18:35 ` Devin Heitmueller
2012-08-06 18:57 ` Michael Krufky
2012-08-06 19:13 ` Antti Palosaari
2012-08-06 20:19 ` Manu Abraham
2012-09-20 17:47 ` Michael Krufky
2012-09-20 17:49 ` Michael Krufky
2012-09-22 17:21 ` Antti Palosaari
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