Hi Niklas,
On Fri, Nov 02, 2018 at 11:44:25AM +0100, Niklas Söderlund wrote:
> Hi Jacopo,
>
> Thanks for your feedback.
>
> On 2018-10-05 12:46:15 +0200, Jacopo Mondi wrote:
> > Hi Niklas,
> >
> > On Thu, Oct 04, 2018 at 10:41:38PM +0200, Niklas Söderlund wrote:
> > > From: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>
> > >
> > > 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@xxxxxxxxxxxx>
> > >
> > > ---
> > > * 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 | 132 ++++++++++++-----------
> > > 1 file changed, 67 insertions(+), 65 deletions(-)
> > >
> > > diff --git a/drivers/media/i2c/adv748x/adv748x-core.c b/drivers/media/i2c/adv748x/adv748x-core.c
> > > index 3836dd3025d6ffb7..fe29781368a3a6b6 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)
> >
> > Am I wrong or the return error is ignored and could be dropped?
>
> No it's used to reduce boiler plate code, see adv748x_power_up_tx()
> bellow for one example.
I meant the function return value. It is never checked:
adv748x_write_check(state, page, 0x31, 0x82, &ret);
>
> int ret = 0;
> ...
> adv748x_write_check(state, page, 0x31, 0x82, &ret);
> adv748x_write_check(state, page, 0x1e, 0x40, &ret);
> ...
> return ret;
>
> If the first adv748x_write_check() fails all later calls to
> adv748x_write_check() will do nothing. This is do avoid the rather hard
> to read:
>
> ret = adv748x_write(state, page, 0x31, 0x82);
> if (ret)
> return ret;
>
> ret = adv748x_write(state, page, 0x1e, 0x40);
> if (ret)
> return ret;
>
> >
> > > +{
> > > + 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.
> > > *
> > > @@ -231,69 +241,63 @@ 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, 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, 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 4-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 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);
> > > + 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 4-lane MIPI */
> > > + 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);
> > > +
> > > + /* ADI Required Write */
> > > + adv748x_write_check(state, page, 0xc1, 0x3b, &ret);
> > > +
> > > + return ret;
> > > +}
> >
> > This one looks good to me
> >
> > >
> > > int adv748x_tx_power(struct adv748x_csi2 *tx, bool on)
> > > {
> > > - struct adv748x_state *state = tx->state;
> > > - const struct adv748x_reg_value *reglist;
> > > - int val;
> > > + int val, ret;
> > >
> > > if (!is_tx_enabled(tx))
> > > return 0;
> > > @@ -311,13 +315,11 @@ int adv748x_tx_power(struct adv748x_csi2 *tx, bool on)
> > > "Enabling with unknown bit set");
> > >
> > > if (on)
> > > - reglist = is_txa(tx) ? adv748x_power_up_txa_4lane :
> > > - adv748x_power_up_txb_1lane;
> > > + ret = adv748x_power_up_tx(tx);
> > > else
> > > - reglist = is_txa(tx) ? adv748x_power_down_txa_4lane :
> > > - adv748x_power_down_txb_1lane;
> > > + ret = adv748x_power_down_tx(tx);
> > >
> > > - return adv748x_write_regs(state, reglist);
> > > + return ret;
> >
> > As Laurent suggested, or even
> > return on ? adv748x_power_up_tx(tx) : adv748x_power_down_tx(tx);
>
> Good idea!
>
> >
> > Thanks
> > j
> >
> > > }
> > >
> > > /* -----------------------------------------------------------------------------
> > > --
> > > 2.19.0
> > >
>
>
>
> --
> Regards,
> Niklas Söderlund
Attachment:
signature.asc
Description: PGP signature
