| Message ID | 1412070294-5535-1-git-send-email-zyw@rock-chips.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Chris, On Tue, Sep 30, 2014 at 2:44 AM, Chris Zhong <zyw@rock-chips.com> wrote: > The min_uv in DCDC1 & DCDC2 should be 712.5mv > > Signed-off-by: Chris Zhong <zyw@rock-chips.com> > > --- > > drivers/regulator/rk808-regulator.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/regulator/rk808-regulator.c b/drivers/regulator/rk808-regulator.c > index e305416..196a5c8 100644 > --- a/drivers/regulator/rk808-regulator.c > +++ b/drivers/regulator/rk808-regulator.c > @@ -44,7 +44,7 @@ static const int rk808_buck_config_regs[] = { > }; > > static const struct regulator_linear_range rk808_buck_voltage_ranges[] = { > - REGULATOR_LINEAR_RANGE(700000, 0, 63, 12500), > + REGULATOR_LINEAR_RANGE(712500, 0, 63, 12500), > }; I have no problem with this (and the current "dts" file I see don't go this low anyway), but it doesn't match the datasheet I have right now which says "0.700 V" is the min. -Doug
Am Dienstag, 30. September 2014, 09:43:47 schrieb Doug Anderson: > Chris, > > On Tue, Sep 30, 2014 at 2:44 AM, Chris Zhong <zyw@rock-chips.com> wrote: > > The min_uv in DCDC1 & DCDC2 should be 712.5mv > > > > Signed-off-by: Chris Zhong <zyw@rock-chips.com> > > > > --- > > > > drivers/regulator/rk808-regulator.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/regulator/rk808-regulator.c > > b/drivers/regulator/rk808-regulator.c index e305416..196a5c8 100644 > > --- a/drivers/regulator/rk808-regulator.c > > +++ b/drivers/regulator/rk808-regulator.c > > @@ -44,7 +44,7 @@ static const int rk808_buck_config_regs[] = { > > > > }; > > > > static const struct regulator_linear_range rk808_buck_voltage_ranges[] = > > { > > > > - REGULATOR_LINEAR_RANGE(700000, 0, 63, 12500), > > + REGULATOR_LINEAR_RANGE(712500, 0, 63, 12500), > > > > }; > > I have no problem with this (and the current "dts" file I see don't go > this low anyway), but it doesn't match the datasheet I have right now > which says "0.700 V" is the min. Then it would be problem. The original statement above says, that a register value of "0" equals 700mV, so changing this in this way would mean everything runs 12.5mV above the target voltage. And I can confirm, that the current datasheet lists 700mV as equallying register value 0.
On Tue, Sep 30, 2014 at 06:57:51PM +0200, Heiko Stübner wrote: > Am Dienstag, 30. September 2014, 09:43:47 schrieb Doug Anderson: > > On Tue, Sep 30, 2014 at 2:44 AM, Chris Zhong <zyw@rock-chips.com> wrote: > > > - REGULATOR_LINEAR_RANGE(700000, 0, 63, 12500), > > > + REGULATOR_LINEAR_RANGE(712500, 0, 63, 12500), > > I have no problem with this (and the current "dts" file I see don't go > > this low anyway), but it doesn't match the datasheet I have right now > > which says "0.700 V" is the min. > Then it would be problem. > The original statement above says, that a register value of "0" equals 700mV, > so changing this in this way would mean everything runs 12.5mV above the > target voltage. > And I can confirm, that the current datasheet lists 700mV as equallying > register value 0. Has anyone got a voltmeter?
On 10/01/2014 06:52 AM, Mark Brown wrote: > On Tue, Sep 30, 2014 at 06:57:51PM +0200, Heiko Stübner wrote: >> Am Dienstag, 30. September 2014, 09:43:47 schrieb Doug Anderson: >>> On Tue, Sep 30, 2014 at 2:44 AM, Chris Zhong <zyw@rock-chips.com> wrote: >>>> - REGULATOR_LINEAR_RANGE(700000, 0, 63, 12500), >>>> + REGULATOR_LINEAR_RANGE(712500, 0, 63, 12500), >>> I have no problem with this (and the current "dts" file I see don't go >>> this low anyway), but it doesn't match the datasheet I have right now >>> which says "0.700 V" is the min. >> Then it would be problem. >> The original statement above says, that a register value of "0" equals 700mV, >> so changing this in this way would mean everything runs 12.5mV above the >> target voltage. >> And I can confirm, that the current datasheet lists 700mV as equallying >> register value 0. > Has anyone got a voltmeter? The latest datasheet has fixed this error. The register value of "0" equals 712.5mV, so the max value can reach 1.5v but not 1.4875v.
Chris and Mark, On Mon, Oct 6, 2014 at 8:29 PM, Chris Zhong <zyw@rock-chips.com> wrote: > > On 10/01/2014 06:52 AM, Mark Brown wrote: >> >> On Tue, Sep 30, 2014 at 06:57:51PM +0200, Heiko Stübner wrote: >>> >>> Am Dienstag, 30. September 2014, 09:43:47 schrieb Doug Anderson: >>>> >>>> On Tue, Sep 30, 2014 at 2:44 AM, Chris Zhong <zyw@rock-chips.com> wrote: >>>>> >>>>> - REGULATOR_LINEAR_RANGE(700000, 0, 63, 12500), >>>>> + REGULATOR_LINEAR_RANGE(712500, 0, 63, 12500), >>>> >>>> I have no problem with this (and the current "dts" file I see don't go >>>> this low anyway), but it doesn't match the datasheet I have right now >>>> which says "0.700 V" is the min. >>> >>> Then it would be problem. >>> The original statement above says, that a register value of "0" equals >>> 700mV, >>> so changing this in this way would mean everything runs 12.5mV above the >>> target voltage. >>> And I can confirm, that the current datasheet lists 700mV as equallying >>> register value 0. >> >> Has anyone got a voltmeter? > > The latest datasheet has fixed this error. > The register value of "0" equals 712.5mV, so the max value can reach 1.5v > but not 1.4875v. OK, that sounds like this is the right change, then. To Mark's point, I measured voltage using the builtin voltage measurement feature this board (not 100% sure the accuracy / precision guarantees on them, but...): Asked for 1.300 volts on vdd_arm (dcdc1). * Before: got 1.326 * After: got 1.310 Asked for 1.3 on vdd_gpu (dcdc2): * Before: 1.326 * After: got 1.314 Asked for 1.0 on vdd_gpu: * Before: 1.038 * After: got 1.026 Asked for .8 on vdd_gpu * Before:.836 * After: got .822 It almost sounds like we're still running a little too high for voltages, but this gets us in the right direction I guess. -Doug
On Tue, Sep 30, 2014 at 05:44:54PM +0800, Chris Zhong wrote:
> The min_uv in DCDC1 & DCDC2 should be 712.5mv
Applied, thanks.
diff --git a/drivers/regulator/rk808-regulator.c b/drivers/regulator/rk808-regulator.c index e305416..196a5c8 100644 --- a/drivers/regulator/rk808-regulator.c +++ b/drivers/regulator/rk808-regulator.c @@ -44,7 +44,7 @@ static const int rk808_buck_config_regs[] = { }; static const struct regulator_linear_range rk808_buck_voltage_ranges[] = { - REGULATOR_LINEAR_RANGE(700000, 0, 63, 12500), + REGULATOR_LINEAR_RANGE(712500, 0, 63, 12500), }; static const struct regulator_linear_range rk808_buck4_voltage_ranges[] = {
The min_uv in DCDC1 & DCDC2 should be 712.5mv Signed-off-by: Chris Zhong <zyw@rock-chips.com> --- drivers/regulator/rk808-regulator.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)