diff mbox series

[v2] arm: dts: am33xx-bone-common: add gpio-line-names

Message ID 20200520214757.GA362547@x1 (mailing list archive)
State New, archived
Headers show
Series [v2] arm: dts: am33xx-bone-common: add gpio-line-names | expand

Commit Message

Drew Fustini May 20, 2020, 9:47 p.m. UTC 
Add gpio-line-names properties to the GPIO controller nodes.

BeagleBone boards have P8 and P9 headers [0] which expose many of the
AM3358 ZCZ SoC balls to stacking expansion boards called "capes", or to
other external connections like jumper wires connected to a breadboard.
BeagleBone users will often refer to the "Cape Exanpsion Headers" pin
diagram [1] as it is in the "Bone101" getting started tutorial. [2]

Most of the P8 and P9 header pins can muxed to a GPIO line.  The
gpio-line-names describe which P8 or P9 pin that line goes to and the
default mux for that P8 or P9 pin if it is not GPIO.

For example, gpiochip 1 line 0 is connected to P8 header pin 25 (P8_25)
however the default device tree has the corresponding BGA ball (ZCZ U7)
muxed to mmc1_dat0 as it is used for the on-board eMMC chip.  For that
GPIO line to be used, one would need to modify the device tree to
disable the eMMC and change the pin mux for that ball to GPIO mode.

Some of the AM3358 ZCZ balls corresponding to GPIO lines are not routed
to a P8 or P9 header, but are instead wired to some peripheral device
like on-board eMMC, HDMI framer IC, or status LEDs.  Those names are in
brackets to denote those GPIO lines can not be used.

Some GPIO lines are named "[NC]" as the corresponding balls are not
routed to anything on the PCB.

The goal for these names is to make it easier for a user viewing the
output of gpioinfo to determine which P8 or P9 pin is connected to a
GPIO line.  The output of gpioinfo on a BeagleBone Black would be:

debian@beaglebone:~$ gpioinfo
gpiochip0 - 32 lines:
	line   0: "[ethernet]"       unused   input  active-high
	line   1: "[ethernet]"       unused   input  active-high
	line   2: "P9_22 [spi0_sclk]" unused input active-high
	line   3: "P9_21 [spi0_d0]" unused input active-high
	line   4: "P9_18 [spi0_d1]" unused input active-high
	line   5: "P9_17 [spi0_cs0]" unused input active-high
	line   6:  "[sd card]"         "cd"   input   active-low [used]
	line   7: "P9_42A [ecappwm0]" unused input active-high
	line   8: "P8_35 [hdmi]" unused input active-high
	line   9: "P8_33 [hdmi]" unused input active-high
	line  10: "P8_31 [hdmi]" unused input active-high
	line  11: "P8_32 [hdmi]" unused input active-high
	line  12: "P9_20 [i2c2_sda]" unused input active-high
	line  13: "P9_19 [i2c2_scl]" unused input active-high
	line  14: "P9_26 [uart1_rxd]" unused input active-high
	line  15: "P9_24 [uart1_txd]" unused input active-high
	line  16: "[ethernet]"       unused   input  active-high
	line  17: "[ethernet]"       unused   input  active-high
	line  18:      "[usb]"       unused   input  active-high
	line  19:     "[hdmi]"       unused   input  active-high
	line  20:     "P9_41B"       unused   input  active-high
	line  21: "[ethernet]"       unused   input  active-high
	line  22: "P8_19 [ehrpwm2a]" unused input active-high
	line  23: "P8_13 [ehrpwm2b]" unused input active-high
	line  24:       "[NC]"       unused   input  active-high
	line  25:       "[NC]"       unused   input  active-high
	line  26:      "P8_14"       unused   input  active-high
	line  27:      "P8_17"       unused   input  active-high
	line  28: "[ethernet]"       unused   input  active-high
	line  29: "[ethernet]"       unused   input  active-high
	line  30: "P9_11 [uart4_rxd]" unused input active-high
	line  31: "P9_13 [uart4_txd]" unused input active-high
gpiochip1 - 32 lines:
	line   0: "P8_25 [emmc]" unused input active-high
	line   1:     "[emmc]"       unused   input  active-high
	line   2: "P8_5 [emmc]" unused input active-high
	line   3: "P8_6 [emmc]" unused input active-high
	line   4: "P8_23 [emmc]" unused input active-high
	line   5: "P8_22 [emmc]" unused input active-high
	line   6: "P8_3 [emmc]" unused input active-high
	line   7: "P8_4 [emmc]" unused input active-high
	line   8:       "[NC]"       unused   input  active-high
	line   9:       "[NC]"       unused   input  active-high
	line  10:       "[NC]"       unused   input  active-high
	line  11:       "[NC]"       unused   input  active-high
	line  12:      "P8_12"       unused   input  active-high
	line  13:      "P8_11"       unused   input  active-high
	line  14:      "P8_16"       unused   input  active-high
	line  15:      "P8_15"       unused   input  active-high
	line  16:     "P9_15A"       unused   input  active-high
	line  17:      "P9_23"       unused   input  active-high
	line  18: "P9_14 [ehrpwm1a]" unused input active-high
	line  19: "P9_16 [ehrpwm1b]" unused input active-high
	line  20:     "[emmc]"       unused   input  active-high
	line  21: "[usr0 led]" "beaglebone:green:heartbeat" output active-high [used]
	line  22: "[usr1 led]" "beaglebone:green:mmc0" output active-high [used]
	line  23: "[usr2 led]" "beaglebone:green:usr2" output active-high [used]
	line  24: "[usr3 led]" "beaglebone:green:usr3" output active-high [used]
	line  25:     "[hdmi]"  "interrupt"   input  active-high [used]
	line  26:      "[usb]"       unused   input  active-high
	line  27: "[hdmi audio]" "enable" output active-high [used]
	line  28:      "P9_12"       unused   input  active-high
	line  29:      "P8_26"       unused   input  active-high
	line  30: "P8_21 [emmc]" unused input active-high
	line  31: "P8_20 [emmc]" unused input active-high
gpiochip2 - 32 lines:
	line   0:     "P9_15B"       unused   input  active-high
	line   1:      "P8_18"       unused   input  active-high
	line   2:       "P8_7"       unused   input  active-high
	line   3:       "P8_8"       unused   input  active-high
	line   4:      "P8_10"       unused   input  active-high
	line   5:       "P8_9"       unused   input  active-high
	line   6: "P8_45 [hdmi]" unused input active-high
	line   7: "P8_46 [hdmi]" unused input active-high
	line   8: "P8_43 [hdmi]" unused input active-high
	line   9: "P8_44 [hdmi]" unused input active-high
	line  10: "P8_41 [hdmi]" unused input active-high
	line  11: "P8_42 [hdmi]" unused input active-high
	line  12: "P8_39 [hdmi]" unused input active-high
	line  13: "P8_40 [hdmi]" unused input active-high
	line  14: "P8_37 [hdmi]" unused input active-high
	line  15: "P8_38 [hdmi]" unused input active-high
	line  16: "P8_36 [hdmi]" unused input active-high
	line  17: "P8_34 [hdmi]" unused input active-high
	line  18: "[ethernet]"       unused   input  active-high
	line  19: "[ethernet]"       unused   input  active-high
	line  20: "[ethernet]"       unused   input  active-high
	line  21: "[ethernet]"       unused   input  active-high
	line  22: "P8_27 [hdmi]" unused input active-high
	line  23: "P8_29 [hdmi]" unused input active-high
	line  24: "P8_28 [hdmi]" unused input active-high
	line  25: "P8_30 [hdmi]" unused input active-high
	line  26:     "[emmc]"       unused   input  active-high
	line  27:     "[emmc]"       unused   input  active-high
	line  28:     "[emmc]"       unused   input  active-high
	line  29:     "[emmc]"       unused   input  active-high
	line  30:     "[emmc]"       unused   input  active-high
	line  31:     "[emmc]"       unused   input  active-high
gpiochip3 - 32 lines:
	line   0: "[ethernet]"       unused   input  active-high
	line   1: "[ethernet]"       unused   input  active-high
	line   2: "[ethernet]"       unused   input  active-high
	line   3: "[ethernet]"       unused   input  active-high
	line   4: "[ethernet]"       unused   input  active-high
	line   5:     "[i2c0]"       unused   input  active-high
	line   6:     "[i2c0]"       unused   input  active-high
	line   7:      "[emu]"       unused   input  active-high
	line   8:      "[emu]"       unused   input  active-high
	line   9: "[ethernet]"       unused   input  active-high
	line  10: "[ethernet]"       unused   input  active-high
	line  11:       "[NC]"       unused   input  active-high
	line  12:       "[NC]"       unused   input  active-high
	line  13:      "[usb]"       unused   input  active-high
	line  14: "P9_31 [spi1_sclk]" unused input active-high
	line  15: "P9_29 [spi1_d0]" unused input active-high
	line  16: "P9_30 [spi1_d1]" unused input active-high
	line  17: "P9_28 [spi1_cs0]" unused input active-high
	line  18: "P9_42B [ecappwm0]" unused input active-high
	line  19:      "P9_27"       unused   input  active-high
	line  20:     "P9_41A"       unused   input  active-high
	line  21:      "P9_25"       unused   input  active-high
	line  22:       "[NC]"       unused   input  active-high
	line  23:       "[NC]"       unused   input  active-high
	line  24:       "[NC]"       unused   input  active-high
	line  25:       "[NC]"       unused   input  active-high
	line  26:       "[NC]"       unused   input  active-high
	line  27:       "[NC]"       unused   input  active-high
	line  28:       "[NC]"       unused   input  active-high
	line  29:       "[NC]"       unused   input  active-high
	line  30:       "[NC]"       unused   input  active-high
	line  31:       "[NC]"       unused   input  active-high

[0] https://git.io/JfgOd
[1] https://beagleboard.org/capes
[1] https://beagleboard.org/Support/bone101
[2] https://beagleboard.org/static/images/cape-headers.png

Reviewed-by: Jason Kridner <jason@beagleboard.org>
Reviewed-by: Robert Nelson <robertcnelson@gmail.com>
Signed-off-by: Drew Fustini <drew@beagleboard.org>
---
 arch/arm/boot/dts/am335x-bone-common.dtsi | 144 ++++++++++++++++++++++
 1 file changed, 144 insertions(+)

Comments

Grygorii Strashko May 21, 2020, 2:34 p.m. UTC | #1 
On 21/05/2020 00:47, Drew Fustini wrote:
> Add gpio-line-names properties to the GPIO controller nodes.
> 
> BeagleBone boards have P8 and P9 headers [0] which expose many of the
> AM3358 ZCZ SoC balls to stacking expansion boards called "capes", or to
> other external connections like jumper wires connected to a breadboard.
> BeagleBone users will often refer to the "Cape Exanpsion Headers" pin
> diagram [1] as it is in the "Bone101" getting started tutorial. [2]
> 
> Most of the P8 and P9 header pins can muxed to a GPIO line.  The
> gpio-line-names describe which P8 or P9 pin that line goes to and the
> default mux for that P8 or P9 pin if it is not GPIO.
> 
> For example, gpiochip 1 line 0 is connected to P8 header pin 25 (P8_25)
> however the default device tree has the corresponding BGA ball (ZCZ U7)
> muxed to mmc1_dat0 as it is used for the on-board eMMC chip.  For that
> GPIO line to be used, one would need to modify the device tree to
> disable the eMMC and change the pin mux for that ball to GPIO mode.
> 
> Some of the AM3358 ZCZ balls corresponding to GPIO lines are not routed
> to a P8 or P9 header, but are instead wired to some peripheral device
> like on-board eMMC, HDMI framer IC, or status LEDs.  Those names are in
> brackets to denote those GPIO lines can not be used.
> 
> Some GPIO lines are named "[NC]" as the corresponding balls are not
> routed to anything on the PCB.
> 
> The goal for these names is to make it easier for a user viewing the
> output of gpioinfo to determine which P8 or P9 pin is connected to a
> GPIO line.  The output of gpioinfo on a BeagleBone Black would be:
> 
> debian@beaglebone:~$ gpioinfo
> gpiochip0 - 32 lines:
> 	line   0: "[ethernet]"       unused   input  active-high
> 	line   1: "[ethernet]"       unused   input  active-high
> 	line   2: "P9_22 [spi0_sclk]" unused input active-high
> 	line   3: "P9_21 [spi0_d0]" unused input active-high
> 	line   4: "P9_18 [spi0_d1]" unused input active-high
> 	line   5: "P9_17 [spi0_cs0]" unused input active-high
> 	line   6:  "[sd card]"         "cd"   input   active-low [used]
> 	line   7: "P9_42A [ecappwm0]" unused input active-high
> 	line   8: "P8_35 [hdmi]" unused input active-high
> 	line   9: "P8_33 [hdmi]" unused input active-high
> 	line  10: "P8_31 [hdmi]" unused input active-high
> 	line  11: "P8_32 [hdmi]" unused input active-high

[...]

> 
> [0] https://git.io/JfgOd
> [1] https://beagleboard.org/capes
> [1] https://beagleboard.org/Support/bone101
> [2] https://beagleboard.org/static/images/cape-headers.png
> 
> Reviewed-by: Jason Kridner <jason@beagleboard.org>
> Reviewed-by: Robert Nelson <robertcnelson@gmail.com>
> Signed-off-by: Drew Fustini <drew@beagleboard.org>
> ---
>   arch/arm/boot/dts/am335x-bone-common.dtsi | 144 ++++++++++++++++++++++

Not sure if it should be in am335x-bone-common.dtsi.

For example:
am335x-boneblack.dts
  #include "am335x-bone-common.dtsi"
  #include "am335x-boneblack-common.dtsi" <-- hdmi defined only here

am335x-bonegreen.dts
  #include "am335x-bone-common.dtsi"
  #include "am335x-bonegreen-common.dtsi"

>   1 file changed, 144 insertions(+)
> 
> diff --git a/arch/arm/boot/dts/am335x-bone-common.dtsi b/arch/arm/boot/dts/am335x-bone-common.dtsi
> index 6c9187bc0f17..d86e67b0e852 100644
> --- a/arch/arm/boot/dts/am335x-bone-common.dtsi
> +++ b/arch/arm/boot/dts/am335x-bone-common.dtsi
> @@ -397,3 +397,147 @@ &rtc {
>   	clocks = <&clk_32768_ck>, <&clk_24mhz_clkctrl AM3_CLK_24MHZ_CLKDIV32K_CLKCTRL 0>;
>   	clock-names = "ext-clk", "int-clk";
>   };
> +
> +&gpio0 {
> +	gpio-line-names =
> +		"[ethernet]",
> +		"[ethernet]",
> +		"P9_22 [spi0_sclk]",
> +		"P9_21 [spi0_d0]",
> +		"P9_18 [spi0_d1]",
> +		"P9_17 [spi0_cs0]",
> +		"[sd card]",
> +		"P9_42A [ecappwm0]",
> +		"P8_35 [hdmi]",
> +		"P8_33 [hdmi]",
> +		"P8_31 [hdmi]",
> +		"P8_32 [hdmi]",

[...]
Robert Nelson May 21, 2020, 2:41 p.m. UTC | #2 
> Not sure if it should be in am335x-bone-common.dtsi.
>
> For example:
> am335x-boneblack.dts
>   #include "am335x-bone-common.dtsi"
>   #include "am335x-boneblack-common.dtsi" <-- hdmi defined only here

Ah crap, yeah that's a good point.. So if we stick it in...
am335x-boneblack-common.dtsi

Then the Black-Wireless now has Ethernet...

am335x-boneblack-wireless.dts
#include "am335x-bone-common.dtsi"
#include "am335x-boneblack-common.dtsi"

It's going to be ugly, copy and paste mess, but i guess we might as
well stick it in the device " am335x-boneblack.dts"?

Regards,
Grygorii Strashko May 21, 2020, 5:26 p.m. UTC | #3 
On 21/05/2020 17:41, Robert Nelson wrote:
>> Not sure if it should be in am335x-bone-common.dtsi.
>>
>> For example:
>> am335x-boneblack.dts
>>    #include "am335x-bone-common.dtsi"
>>    #include "am335x-boneblack-common.dtsi" <-- hdmi defined only here
> 
> Ah crap, yeah that's a good point.. So if we stick it in...
> am335x-boneblack-common.dtsi
> 
> Then the Black-Wireless now has Ethernet...
> 
> am335x-boneblack-wireless.dts
> #include "am335x-bone-common.dtsi"
> #include "am335x-boneblack-common.dtsi"
> 
> It's going to be ugly, copy and paste mess, but i guess we might as
> well stick it in the device " am335x-boneblack.dts"?

Seems like.

Unfortunately, there is no way to partially overwrite "gpio-line-names"
property.
Drew Fustini May 21, 2020, 7:23 p.m. UTC | #4 
On Thu, May 21, 2020 at 08:26:42PM +0300, Grygorii Strashko wrote:
> 
> 
> On 21/05/2020 17:41, Robert Nelson wrote:
> > > Not sure if it should be in am335x-bone-common.dtsi.
> > > 
> > > For example:
> > > am335x-boneblack.dts
> > >    #include "am335x-bone-common.dtsi"
> > >    #include "am335x-boneblack-common.dtsi" <-- hdmi defined only here
> > 
> > Ah crap, yeah that's a good point.. So if we stick it in...
> > am335x-boneblack-common.dtsi
> > 
> > Then the Black-Wireless now has Ethernet...
> > 
> > am335x-boneblack-wireless.dts
> > #include "am335x-bone-common.dtsi"
> > #include "am335x-boneblack-common.dtsi"
> > 
> > It's going to be ugly, copy and paste mess, but i guess we might as
> > well stick it in the device " am335x-boneblack.dts"?
> 
> Seems like.
> 
> Unfortunately, there is no way to partially overwrite "gpio-line-names"
> property.
> 
> -- 
> Best regards,
> grygorii

Thank you for pointing out that those gpio-line-names are really
specific to the BeagleBone Black and not applicable for other boards
like the BeagleBone Green which lack eMMC.

I will post a new patch for am335x-boneblack.dts.

After that is reviewed and applied, I will then create patches for the
the other BeagleBone models.

thanks,
drew
diff mbox series

Patch

diff --git a/arch/arm/boot/dts/am335x-bone-common.dtsi b/arch/arm/boot/dts/am335x-bone-common.dtsi
index 6c9187bc0f17..d86e67b0e852 100644
--- a/arch/arm/boot/dts/am335x-bone-common.dtsi
+++ b/arch/arm/boot/dts/am335x-bone-common.dtsi
@@ -397,3 +397,147 @@  &rtc {
 	clocks = <&clk_32768_ck>, <&clk_24mhz_clkctrl AM3_CLK_24MHZ_CLKDIV32K_CLKCTRL 0>;
 	clock-names = "ext-clk", "int-clk";
 };
+
+&gpio0 {
+	gpio-line-names =
+		"[ethernet]",
+		"[ethernet]",
+		"P9_22 [spi0_sclk]",
+		"P9_21 [spi0_d0]",
+		"P9_18 [spi0_d1]",
+		"P9_17 [spi0_cs0]",
+		"[sd card]",
+		"P9_42A [ecappwm0]",
+		"P8_35 [hdmi]",
+		"P8_33 [hdmi]",
+		"P8_31 [hdmi]",
+		"P8_32 [hdmi]",
+		"P9_20 [i2c2_sda]",
+		"P9_19 [i2c2_scl]",
+		"P9_26 [uart1_rxd]",
+		"P9_24 [uart1_txd]",
+		"[ethernet]",
+		"[ethernet]",
+		"[usb]",
+		"[hdmi]",
+		"P9_41B",
+		"[ethernet]",
+		"P8_19 [ehrpwm2a]",
+		"P8_13 [ehrpwm2b]",
+		"[NC]",
+		"[NC]",
+		"P8_14",
+		"P8_17",
+		"[ethernet]",
+		"[ethernet]",
+		"P9_11 [uart4_rxd]",
+		"P9_13 [uart4_txd]";
+};
+
+&gpio1 {
+	gpio-line-names =
+		"P8_25 [emmc]",
+		"[emmc]",
+		"P8_5 [emmc]",
+		"P8_6 [emmc]",
+		"P8_23 [emmc]",
+		"P8_22 [emmc]",
+		"P8_3 [emmc]",
+		"P8_4 [emmc]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"P8_12",
+		"P8_11",
+		"P8_16",
+		"P8_15",
+		"P9_15A",
+		"P9_23",
+		"P9_14 [ehrpwm1a]",
+		"P9_16 [ehrpwm1b]",
+		"[emmc]",
+		"[usr0 led]",
+		"[usr1 led]",
+		"[usr2 led]",
+		"[usr3 led]",
+		"[hdmi]",
+		"[usb]",
+		"[hdmi audio]",
+		"P9_12",
+		"P8_26",
+		"P8_21 [emmc]",
+		"P8_20 [emmc]";
+};
+
+&gpio2 {
+	gpio-line-names =
+		"P9_15B",
+		"P8_18",
+		"P8_7",
+		"P8_8",
+		"P8_10",
+		"P8_9",
+		"P8_45 [hdmi]",
+		"P8_46 [hdmi]",
+		"P8_43 [hdmi]",
+		"P8_44 [hdmi]",
+		"P8_41 [hdmi]",
+		"P8_42 [hdmi]",
+		"P8_39 [hdmi]",
+		"P8_40 [hdmi]",
+		"P8_37 [hdmi]",
+		"P8_38 [hdmi]",
+		"P8_36 [hdmi]",
+		"P8_34 [hdmi]",
+		"[ethernet]",
+		"[ethernet]",
+		"[ethernet]",
+		"[ethernet]",
+		"P8_27 [hdmi]",
+		"P8_29 [hdmi]",
+		"P8_28 [hdmi]",
+		"P8_30 [hdmi]",
+		"[emmc]",
+		"[emmc]",
+		"[emmc]",
+		"[emmc]",
+		"[emmc]",
+		"[emmc]";
+};
+
+&gpio3 {
+	gpio-line-names =
+		"[ethernet]",
+		"[ethernet]",
+		"[ethernet]",
+		"[ethernet]",
+		"[ethernet]",
+		"[i2c0]",
+		"[i2c0]",
+		"[emu]",
+		"[emu]",
+		"[ethernet]",
+		"[ethernet]",
+		"[NC]",
+		"[NC]",
+		"[usb]",
+		"P9_31 [spi1_sclk]",
+		"P9_29 [spi1_d0]",
+		"P9_30 [spi1_d1]",
+		"P9_28 [spi1_cs0]",
+		"P9_42B [ecappwm0]",
+		"P9_27",
+		"P9_41A",
+		"P9_25",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]",
+		"[NC]";
+};