Re: [RFT][PATCH 1/2] regulator: lm363x: Fix off-by-one n_voltages for lm3632 ldo_vpos/ldo_vneg

From: Axel Lin <axel.lin@ingics.com>
To: Dan Murphy <dmurphy@ti.com>
Cc: Mark Brown <broonie@kernel.org>,
	Liam Girdwood <lgirdwood@gmail.com>,
	LKML <linux-kernel@vger.kernel.org>
Subject: Re: [RFT][PATCH 1/2] regulator: lm363x: Fix off-by-one n_voltages for lm3632 ldo_vpos/ldo_vneg
Date: Wed, 26 Jun 2019 23:12:55 +0800	[thread overview]
Message-ID: <CAFRkauAewFwcQNzpSfAfXMiCdHuENcg2NRzKECjPQ1RtUCuXEA@mail.gmail.com> (raw)
In-Reply-To: <a99b04a3-f079-3a43-9e19-d9501b76a96e@ti.com>

Dan Murphy <dmurphy@ti.com> 於 2019年6月26日 週三 下午11:07寫道：
>
> Hello
>
> On 6/26/19 8:26 AM, Axel Lin wrote:
> > According to the datasheet https://www.ti.com/lit/ds/symlink/lm3632a.pdf
> > Table 20. VPOS Bias Register Field Descriptions VPOS[5:0]
> > Sets the Positive Display Bias (LDO) Voltage (50 mV per step)
> > 000000: 4 V
> > 000001: 4.05 V
> > 000010: 4.1 V
> > ....................
> > 011101: 5.45 V
> > 011110: 5.5 V (Default)
> > 011111: 5.55 V
> > ....................
> > 100111: 5.95 V
> > 101000: 6 V
> > Note: Codes 101001 to 111111 map to 6 V
> >
> > The LM3632_LDO_VSEL_MAX should be 0b101000 (0x28), so the maximum voltage
> > can match the datasheet.
> >
> > Fixes: 3a8d1a73a037 ("regulator: add LM363X driver")
> > Signed-off-by: Axel Lin <axel.lin@ingics.com>
> > ---
> >   drivers/regulator/lm363x-regulator.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/regulator/lm363x-regulator.c b/drivers/regulator/lm363x-regulator.c
> > index 5647e2f97ff8..e4a27d63bf90 100644
> > --- a/drivers/regulator/lm363x-regulator.c
> > +++ b/drivers/regulator/lm363x-regulator.c
> > @@ -30,7 +30,7 @@
> >
> >   /* LM3632 */
> >   #define LM3632_BOOST_VSEL_MAX               0x26
> > -#define LM3632_LDO_VSEL_MAX          0x29
> > +#define LM3632_LDO_VSEL_MAX          0x28
>
> Similar comment as I made on the LM36274
>
> These are 0 based registers so it is 28 + 1
The code shows:  .n_voltages     = LM3632_LDO_VSEL_MAX + 1
so LM3632_LDO_VSEL_MAX needs to be 0x28.

                .name           = "ldo_vpos",
                .of_match       = "vpos",
                .id             = LM3632_LDO_POS,
                .ops            = &lm363x_regulator_voltage_table_ops,
                .n_voltages     = LM3632_LDO_VSEL_MAX + 1,