Message ID | 20210506100312.1638-3-steven_lee@aspeedtech.com |
---|---|
State | New |
Headers | show |
Series | mmc: sdhci-of-aspeed: Support toggling SD bus signal | expand |
On Thu, 6 May 2021, at 19:33, Steven Lee wrote: > Add the description for describing the AST2600-A2 EVB reference design of > GPIO regulators. > > Signed-off-by: Steven Lee <steven_lee@aspeedtech.com> > --- > arch/arm/boot/dts/aspeed-ast2600-evb.dts | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/arch/arm/boot/dts/aspeed-ast2600-evb.dts > b/arch/arm/boot/dts/aspeed-ast2600-evb.dts > index 2772796e215e..1ae0facc3d5f 100644 > --- a/arch/arm/boot/dts/aspeed-ast2600-evb.dts > +++ b/arch/arm/boot/dts/aspeed-ast2600-evb.dts > @@ -104,6 +104,21 @@ > status = "okay"; > }; > > +/* > + * The signal voltage of sdhci0 and sdhci1 on AST2600-A2 EVB is able to be > + * toggled by GPIO pins. > + * In the reference design, GPIOV0 of AST2600-A2 EVB is connected to the > + * power load switch that providing 3.3v to sdhci0 vdd, GPIOV1 is connected to > + * a 1.8v and a 3.3v power load switch that providing signal voltage to > + * sdhci0 bus. > + * If GPIOV0 is active high, sdhci0 is enabled, otherwise, sdhci0 is disabled. > + * If GPIOV1 is active high, 3.3v power load switch is enabled, sdhci0 signal > + * voltage is 3.3v, otherwise, 1.8v power load switch will be enabled, > + * sdhci0 signal voltage becomes 1.8v. > + * AST2600-A2 EVB also support toggling signal voltage for sdhci1. > + * The design is the same as sdhci0, it uses GPIOV2 as power-gpio and GPIOV3 > + * as power-switch-gpio. > + */ Okay, I think the comment is in the right place, but I feel this patch should also add the regulator nodes and hook them up to the SDHCIs. Given Rob isn't super keen on a second example in the binding document I think you can just cut the example out and paste it in here. Andrew
The 05/07/2021 09:40, Andrew Jeffery wrote: > > > On Thu, 6 May 2021, at 19:33, Steven Lee wrote: > > Add the description for describing the AST2600-A2 EVB reference design of > > GPIO regulators. > > > > Signed-off-by: Steven Lee <steven_lee@aspeedtech.com> > > --- > > arch/arm/boot/dts/aspeed-ast2600-evb.dts | 15 +++++++++++++++ > > 1 file changed, 15 insertions(+) > > > > diff --git a/arch/arm/boot/dts/aspeed-ast2600-evb.dts > > b/arch/arm/boot/dts/aspeed-ast2600-evb.dts > > index 2772796e215e..1ae0facc3d5f 100644 > > --- a/arch/arm/boot/dts/aspeed-ast2600-evb.dts > > +++ b/arch/arm/boot/dts/aspeed-ast2600-evb.dts > > @@ -104,6 +104,21 @@ > > status = "okay"; > > }; > > > > +/* > > + * The signal voltage of sdhci0 and sdhci1 on AST2600-A2 EVB is able to be > > + * toggled by GPIO pins. > > + * In the reference design, GPIOV0 of AST2600-A2 EVB is connected to the > > + * power load switch that providing 3.3v to sdhci0 vdd, GPIOV1 is connected to > > + * a 1.8v and a 3.3v power load switch that providing signal voltage to > > + * sdhci0 bus. > > + * If GPIOV0 is active high, sdhci0 is enabled, otherwise, sdhci0 is disabled. > > + * If GPIOV1 is active high, 3.3v power load switch is enabled, sdhci0 signal > > + * voltage is 3.3v, otherwise, 1.8v power load switch will be enabled, > > + * sdhci0 signal voltage becomes 1.8v. > > + * AST2600-A2 EVB also support toggling signal voltage for sdhci1. > > + * The design is the same as sdhci0, it uses GPIOV2 as power-gpio and GPIOV3 > > + * as power-switch-gpio. > > + */ > > Okay, I think the comment is in the right place, but I feel this patch > should also add the regulator nodes and hook them up to the SDHCIs. > > Given Rob isn't super keen on a second example in the binding document > I think you can just cut the example out and paste it in here. > Hi Andrew, Since AST2600-A0 and AST2600-A1 don't have regulators, do you mean cut the example from dt-binding and paste it to aspeed-ast2600-evb.dts but comment out the example? > Andrew
diff --git a/arch/arm/boot/dts/aspeed-ast2600-evb.dts b/arch/arm/boot/dts/aspeed-ast2600-evb.dts index 2772796e215e..1ae0facc3d5f 100644 --- a/arch/arm/boot/dts/aspeed-ast2600-evb.dts +++ b/arch/arm/boot/dts/aspeed-ast2600-evb.dts @@ -104,6 +104,21 @@ status = "okay"; }; +/* + * The signal voltage of sdhci0 and sdhci1 on AST2600-A2 EVB is able to be + * toggled by GPIO pins. + * In the reference design, GPIOV0 of AST2600-A2 EVB is connected to the + * power load switch that providing 3.3v to sdhci0 vdd, GPIOV1 is connected to + * a 1.8v and a 3.3v power load switch that providing signal voltage to + * sdhci0 bus. + * If GPIOV0 is active high, sdhci0 is enabled, otherwise, sdhci0 is disabled. + * If GPIOV1 is active high, 3.3v power load switch is enabled, sdhci0 signal + * voltage is 3.3v, otherwise, 1.8v power load switch will be enabled, + * sdhci0 signal voltage becomes 1.8v. + * AST2600-A2 EVB also support toggling signal voltage for sdhci1. + * The design is the same as sdhci0, it uses GPIOV2 as power-gpio and GPIOV3 + * as power-switch-gpio. + */ &emmc { non-removable; bus-width = <4>;
Add the description for describing the AST2600-A2 EVB reference design of GPIO regulators. Signed-off-by: Steven Lee <steven_lee@aspeedtech.com> --- arch/arm/boot/dts/aspeed-ast2600-evb.dts | 15 +++++++++++++++ 1 file changed, 15 insertions(+)