From: jacopo mondi <jacopo@jmondi.org>
To: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: "Niklas Söderlund" <niklas.soderlund+renesas@ragnatech.se>,
"Kieran Bingham" <kieran.bingham@ideasonboard.com>,
linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org
Subject: Re: [PATCH v3 4/4] i2c: adv748x: configure number of lanes used for TXA CSI-2 transmitter
Date: Sun, 25 Nov 2018 11:09:04 +0100 [thread overview]
Message-ID: <20181125100904.GE6788@w540> (raw)
In-Reply-To: <2306235.pDioDJoL9o@avalon>
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Hi Laurent,
On Fri, Nov 23, 2018 at 04:43:18PM +0200, Laurent Pinchart wrote:
> Hi Jacopo,
>
> On Friday, 23 November 2018 16:01:54 EET jacopo mondi wrote:
> > On Fri, Nov 02, 2018 at 05:00:09PM +0100, Niklas Söderlund wrote:
> > > The driver fixed the TXA CSI-2 transmitter in 4-lane mode while it could
> > > operate using 1-, 2- and 4-lanes. Update the driver to support all modes
> > > the hardware does.
> > >
> > > The driver make use of large tables of static register/value writes when
> > > powering up/down the TXA and TXB transmitters which include the write to
> > > the NUM_LANES register. By converting the tables into functions and
> > > using parameters the power up/down functions for TXA and TXB power
> > > up/down can be merged and used for both transmitters.
> > >
> > > Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
> > >
> > > ---
> > > * Changes since v2
> > > - Fix typos in comments.
> > > - Remove unneeded boiler plait code in adv748x_tx_power() as suggested
> > >
> > > by Jacopo and Laurent.
> > >
> > > - Take into account the two different register used when powering up TXA
> > >
> > > and TXB due to an earlier patch in this series aligns the power
> > > sequence with the manual.
> > >
> > > * Changes since v1
> > > - Convert tables of register/value writes into functions instead of
> > >
> > > intercepting and modifying the writes to the NUM_LANES register.
> > >
> > > ---
> > >
> > > drivers/media/i2c/adv748x/adv748x-core.c | 157 ++++++++++++-----------
> > > 1 file changed, 79 insertions(+), 78 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/adv748x/adv748x-core.c
> > > b/drivers/media/i2c/adv748x/adv748x-core.c index
> > > 9d80d7f3062b16bc..d94c63cb6a2efdba 100644
> > > --- a/drivers/media/i2c/adv748x/adv748x-core.c
> > > +++ b/drivers/media/i2c/adv748x/adv748x-core.c
> > > @@ -125,6 +125,16 @@ int adv748x_write(struct adv748x_state *state, u8
> > > page, u8 reg, u8 value)
> > > return regmap_write(state->regmap[page], reg, value);
> > > }
> > >
> > > +static int adv748x_write_check(struct adv748x_state *state, u8 page, u8
> > > reg,
> > > + u8 value, int *error)
> > > +{
> > > + if (*error)
> > > + return *error;
> > > +
> > > + *error = adv748x_write(state, page, reg, value);
> > > + return *error;
> > > +}
> > > +
> > > /* adv748x_write_block(): Write raw data with a maximum of
> > > I2C_SMBUS_BLOCK_MAX>
> > > * size to one or more registers.
> > > *
> > > @@ -231,79 +241,77 @@ static int adv748x_write_regs(struct adv748x_state
> > > *state,
> > > * TXA and TXB
> > > */
> > >
> > > -static const struct adv748x_reg_value adv748x_power_up_txa_4lane[] = {
> > > -
> > > - {ADV748X_PAGE_TXA, 0x00, 0x84}, /* Enable 4-lane MIPI */
> > > - {ADV748X_PAGE_TXA, 0x00, 0xa4}, /* Set Auto DPHY Timing */
> > > - {ADV748X_PAGE_TXA, 0xdb, 0x10}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0xd6, 0x07}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0xc4, 0x0a}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0x71, 0x33}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0x72, 0x11}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0xf0, 0x00}, /* i2c_dphy_pwdn - 1'b0 */
> > > -
> > > - {ADV748X_PAGE_TXA, 0x31, 0x82}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0x1e, 0x40}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0xda, 0x01}, /* i2c_mipi_pll_en - 1'b1 */
> > > - {ADV748X_PAGE_WAIT, 0x00, 0x02},/* delay 2 */
> > > - {ADV748X_PAGE_TXA, 0x00, 0x24 },/* Power-up CSI-TX */
> > > - {ADV748X_PAGE_WAIT, 0x00, 0x01},/* delay 1 */
> > > - {ADV748X_PAGE_TXA, 0xc1, 0x2b}, /* ADI Required Write */
> > > - {ADV748X_PAGE_WAIT, 0x00, 0x01},/* delay 1 */
> > > - {ADV748X_PAGE_TXA, 0x31, 0x80}, /* ADI Required Write */
> > > -
> > > - {ADV748X_PAGE_EOR, 0xff, 0xff} /* End of register table */
> > > -};
> > > -
> > > -static const struct adv748x_reg_value adv748x_power_down_txa_4lane[] = {
> > > -
> > > - {ADV748X_PAGE_TXA, 0x31, 0x82}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0x1e, 0x00}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXA, 0x00, 0x84}, /* Enable 4-lane MIPI */
> > > - {ADV748X_PAGE_TXA, 0xda, 0x01}, /* i2c_mipi_pll_en - 1'b1 */
> > > - {ADV748X_PAGE_TXA, 0xc1, 0x3b}, /* ADI Required Write */
> > > -
> > > - {ADV748X_PAGE_EOR, 0xff, 0xff} /* End of register table */
> > > -};
> > > -
> > > -static const struct adv748x_reg_value adv748x_power_up_txb_1lane[] = {
> > > -
> > > - {ADV748X_PAGE_TXB, 0x00, 0x81}, /* Enable 1-lane MIPI */
> > > - {ADV748X_PAGE_TXB, 0x00, 0xa1}, /* Set Auto DPHY Timing */
> > > - {ADV748X_PAGE_TXB, 0xd2, 0x40}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0xc4, 0x0a}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0x71, 0x33}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0x72, 0x11}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0xf0, 0x00}, /* i2c_dphy_pwdn - 1'b0 */
> > > -
> > > - {ADV748X_PAGE_TXB, 0x31, 0x82}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0x1e, 0x40}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0xda, 0x01}, /* i2c_mipi_pll_en - 1'b1 */
> > > - {ADV748X_PAGE_WAIT, 0x00, 0x02},/* delay 2 */
> > > - {ADV748X_PAGE_TXB, 0x00, 0x21 },/* Power-up CSI-TX */
> > > - {ADV748X_PAGE_WAIT, 0x00, 0x01},/* delay 1 */
> > > - {ADV748X_PAGE_TXB, 0xc1, 0x2b}, /* ADI Required Write */
> > > - {ADV748X_PAGE_WAIT, 0x00, 0x01},/* delay 1 */
> > > - {ADV748X_PAGE_TXB, 0x31, 0x80}, /* ADI Required Write */
> > > -
> > > - {ADV748X_PAGE_EOR, 0xff, 0xff} /* End of register table */
> > > -};
> > > -
> > > -static const struct adv748x_reg_value adv748x_power_down_txb_1lane[] = {
> > > -
> > > - {ADV748X_PAGE_TXB, 0x31, 0x82}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0x1e, 0x00}, /* ADI Required Write */
> > > - {ADV748X_PAGE_TXB, 0x00, 0x81}, /* Enable 1-lane MIPI */
> > > - {ADV748X_PAGE_TXB, 0xda, 0x01}, /* i2c_mipi_pll_en - 1'b1 */
> > > - {ADV748X_PAGE_TXB, 0xc1, 0x3b}, /* ADI Required Write */
> > > -
> > > - {ADV748X_PAGE_EOR, 0xff, 0xff} /* End of register table */
> > > -};
> > > +static int adv748x_power_up_tx(struct adv748x_csi2 *tx)
> > > +{
> > > + struct adv748x_state *state = tx->state;
> > > + u8 page = is_txa(tx) ? ADV748X_PAGE_TXA : ADV748X_PAGE_TXB;
> > > + int ret = 0;
> > > +
> > > + /* Enable n-lane MIPI */
> > > + adv748x_write_check(state, page, 0x00, 0x80 | tx->num_lanes, &ret);
> > > +
> > > + /* Set Auto DPHY Timing */
> > > + adv748x_write_check(state, page, 0x00, 0xa0 | tx->num_lanes, &ret);
> > > +
> > > + /* ADI Required Write */
> > > + if (is_txa(tx)) {
> > > + adv748x_write_check(state, page, 0xdb, 0x10, &ret);
> > > + adv748x_write_check(state, page, 0xd6, 0x07, &ret);
> > > + } else {
> > > + adv748x_write_check(state, page, 0xd2, 0x40, &ret);
> > > + }
> > > +
> > > + adv748x_write_check(state, page, 0xc4, 0x0a, &ret);
> > > + adv748x_write_check(state, page, 0x71, 0x33, &ret);
> > > + adv748x_write_check(state, page, 0x72, 0x11, &ret);
> > > +
> > > + /* i2c_dphy_pwdn - 1'b0 */
> > > + adv748x_write_check(state, page, 0xf0, 0x00, &ret);
> > > +
> > > + /* ADI Required Writes*/
> > > + adv748x_write_check(state, page, 0x31, 0x82, &ret);
> > > + adv748x_write_check(state, page, 0x1e, 0x40, &ret);
> > > +
> > > + /* i2c_mipi_pll_en - 1'b1 */
> > > + adv748x_write_check(state, page, 0xda, 0x01, &ret);
> > > + usleep_range(2000, 2500);
> > > +
> > > + /* Power-up CSI-TX */
> > > + adv748x_write_check(state, page, 0x00, 0x20 | tx->num_lanes, &ret);
> >
> > Where does the 0x20 come from? I don't see it in the register
> > description in the HW manual..
>
> Isn't it the EN_AUTOCALC_DPHY_PARAMS bit ?
>
Right, I missed that :)
> > > + usleep_range(1000, 1500);
> > > +
> > > + /* ADI Required Writes */
> > > + adv748x_write_check(state, page, 0xc1, 0x2b, &ret);
> > > + usleep_range(1000, 1500);
> > > + adv748x_write_check(state, page, 0x31, 0x80, &ret);
> > > +
> > > + return ret;
> > > +}
> > > +
> > > +static int adv748x_power_down_tx(struct adv748x_csi2 *tx)
> > > +{
> > > + struct adv748x_state *state = tx->state;
> > > + u8 page = is_txa(tx) ? ADV748X_PAGE_TXA : ADV748X_PAGE_TXB;
> > > + int ret = 0;
> > > +
> > > + /* ADI Required Writes */
> > > + adv748x_write_check(state, page, 0x31, 0x82, &ret);
> > > + adv748x_write_check(state, page, 0x1e, 0x00, &ret);
> > > +
> > > + /* Enable n-lane MIPI */
> >
> > The comment is wrong here: this write disables the CSI TX interface.
> >
> > > + adv748x_write_check(state, page, 0x00, 0x80 | tx->num_lanes, &ret);
> > > +
> > > + /* i2c_mipi_pll_en - 1'b1 */
> > > + adv748x_write_check(state, page, 0xda, 0x01, &ret);
> >
> > Re-looking at power up/down sequences, this should actually be 0xda = 0x00,
> > as specified in seciont 9.5.2 of the HW manual.
> >
> > I know all of these come from tables in the previous version and has not
> > been introduced by this patch, but while at there it might be worth
> > fixing them.
> >
> > And actually, I don't like much the comments for registers pll_en and
> > dphy_pdn registers, and they might be improved, since you're rewriting
> > this sequence anyhow.
> >
> > I had a patch pending, before I realized you could change this in your
> > next v4. In case you want to have a look:
> > https://paste.debian.net/1052965/
>
> I would prefer fixes to be made on top of this patch, to separate the
> refactoring from the functional changes as much as possible.
>
Fine. I will send them based on next iteration of this series from
Niklas.
Thanks
j
> > > +
> > > + /* ADI Required Write */
> > > + adv748x_write_check(state, page, 0xc1, 0x3b, &ret);
> > > +
> > > + return ret;
> > > +}
> > >
> > > int adv748x_tx_power(struct adv748x_csi2 *tx, bool on)
> > > {
> > > - struct adv748x_state *state = tx->state;
> > > - const struct adv748x_reg_value *reglist;
> > > int val;
> > >
> > > if (!is_tx_enabled(tx))
> > > @@ -321,14 +329,7 @@ int adv748x_tx_power(struct adv748x_csi2 *tx, bool
> > > on)
> > > WARN_ONCE((on && val & ADV748X_CSI_FS_AS_LS_UNKNOWN),
> > > "Enabling with unknown bit set");
> > >
> > > - if (on)
> > > - reglist = is_txa(tx) ? adv748x_power_up_txa_4lane :
> > > - adv748x_power_up_txb_1lane;
> > > - else
> > > - reglist = is_txa(tx) ? adv748x_power_down_txa_4lane :
> > > - adv748x_power_down_txb_1lane;
> > > -
> > > - return adv748x_write_regs(state, reglist);
> > > + return on ? adv748x_power_up_tx(tx) : adv748x_power_down_tx(tx);
> > > }
> > >
> > > /* ----------------------------------------------------------------------
>
> --
> Regards,
>
> Laurent Pinchart
>
>
>
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next prev parent reply other threads:[~2018-11-25 20:59 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-11-02 16:00 [PATCH v3 0/4] i2c: adv748x: add support for CSI-2 TXA to work Niklas Söderlund
2018-11-02 16:00 ` [PATCH v3 1/4] dt-bindings: adv748x: make data-lanes property mandatory for CSI-2 endpoints Niklas Söderlund
2018-11-05 8:41 ` jacopo mondi
2018-11-05 20:39 ` Rob Herring
2018-11-05 10:43 ` Laurent Pinchart
2018-11-02 16:00 ` [PATCH v3 2/4] i2c: adv748x: reuse power up sequence when initializing CSI-2 Niklas Söderlund
2018-11-05 10:52 ` Laurent Pinchart
2018-11-02 16:00 ` [PATCH v3 3/4] i2c: adv748x: store number of CSI-2 lanes described in device tree Niklas Söderlund
2018-11-05 8:58 ` jacopo mondi
2018-11-05 10:56 ` Laurent Pinchart
2018-11-02 16:00 ` [PATCH v3 4/4] i2c: adv748x: configure number of lanes used for TXA CSI-2 transmitter Niklas Söderlund
2018-11-05 8:47 ` jacopo mondi
2018-11-05 11:01 ` Laurent Pinchart
2018-11-23 14:01 ` jacopo mondi
2018-11-23 14:43 ` Laurent Pinchart
2018-11-25 10:09 ` jacopo mondi [this message]
2018-11-05 10:19 ` [PATCH v3 0/4] i2c: adv748x: add support for CSI-2 TXA to work jacopo mondi
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