Difference between revisions of "DESK-MX6UL-L/Peripherals/USB OTG"

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(Accessing the peripheral)
m (U0007 moved page DESK-MX6UL-L/Pheripherals/USB OTG to DESK-MX6UL-L/Peripherals/USB OTG without leaving a redirect)
 
(8 intermediate revisions by 2 users not shown)
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<section begin=History/>
+
<section begin="History" />
 
{| style="border-collapse:collapse; "
 
{| style="border-collapse:collapse; "
!colspan="4" style="width:100%; text-align:left"; border-bottom:solid 2px #ededed"|History
+
! colspan="4" style="width:100%; text-align:left" ; border-bottom:solid 2px #ededed" |History
 
|-  
 
|-  
!style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white"|Version
+
! style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white" |Issue Date
!style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white"|Issue Date
+
! style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white" |Notes
!style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#73B2C7; padding:5px; color:white"|Notes
 
 
|-
 
|-
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|1.0.0
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| style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000" |{{oldid|14250|2021/07/20}}
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|Apr 2021
+
| style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000" |First DESK-MX6UL-L release
|style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000"|First DESK release
+
|-
 +
| style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000" |{{oldid|16316|2022/03/16}}
 +
| style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#edf8fb; padding:5px; color:#000000" |DESK-MX6UL-L 3.0.0 release
 +
|-
 +
! style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#ededed; padding:5px; color:#000000" |2023/05/04
 +
! style="border-left:solid 2px #73B2C7; border-right:solid 2px #73B2C7;border-top:solid 2px #73B2C7; border-bottom:solid 2px #73B2C7; background-color:#ededed; padding:5px; color:#000000" |DESK-MX6UL-L 4.0.0 release
 
|}
 
|}
<section end=History/>
+
<section end="History" />
<section begin=Body/>
+
<section begin="Body" />
  
 
==Peripheral USB OTG ==
 
==Peripheral USB OTG ==
  
The USB OTG ports can be configured as Host or Device mode depending on the device tree configuration.
+
The USB OTG ports can be configured as Host or Device mode depending on the device tree configuration. In OTG mode they can be easily tested using the Mass Storage Gadget, which lets the device export a file as a mass storage device to the connected PC.
  
In OTG mode they can be easily tested using the Mass Storage Gadget, which lets the device export a file as a mass storage device to the connected PC.
+
{{ImportantMessage|text=The USB OTG peripheral is not available - ''as default option'' - on [[AXEL_ULite_SOM/AXEL_ULite_Evaluation_Kit | AXEL ULite EVK]]. Please contact [mailto:sales@dave.eu Sales department] for this option.<br>
 +
This peripheral is available on the i.MX6UL standard product [[SBC_Lynx_SBC | SBCLynx]]}}
  
 
=== Device tree configuration ===
 
=== Device tree configuration ===
Line 24: Line 29:
 
Here below an example of device tree configuration used on standard DAVE's kit for the [[AXEL ULite SOM]] where USB OTG1 is configured as ''otg'' while the USB OTG2 port is configured in ''host'' mode:
 
Here below an example of device tree configuration used on standard DAVE's kit for the [[AXEL ULite SOM]] where USB OTG1 is configured as ''otg'' while the USB OTG2 port is configured in ''host'' mode:
  
From <code>imx6ul-lynx-som0013.dtsi</code>:
+
From <code>imx6ul-lynx-som0013-cb002f.dts</code>:
  
 
<pre>
 
<pre>
&usbotg1 {
+
pinctrl_usb_otg2: usbotg2grp {
        pinctrl-names = "default";
+
fsl,pins = <
        pinctrl-0 = <&pinctrl_usb_otg1_id>;
+
MX6UL_PAD_ENET2_TX_DATA1__GPIO2_IO12    0x17059 /* OTG2_PWR */
        vbus-supply = <&reg_usb_otg1_vbus>;
+
MX6UL_PAD_ENET2_TX_EN__USB_OTG2_OC      0x17059 /* OTG2_OC */
        dr_mode = "otg";
+
>;
        srp-disable;
+
};
        hnp-disable;
+
};
        adp-disable;
 
        status = "disabled";
 
 
};
 
};
 
&usbotg2 {
 
        vbus-supply = <&reg_usb_otg2_vbus>;
 
        dr_mode = "host";
 
        status = "disabled";
 
};
 
...
 
...
 
&iomuxc {
 
...
 
...
 
pinctrl_usb_otg1_id: usbotg1idgrp {
 
fsl,pins = <
 
MX6UL_PAD_GPIO1_IO00__ANATOP_OTG1_ID    0x17059
 
>;
 
};
 
 
pinctrl_usb_otg1: usbotg1grp {
 
fsl,pins = <
 
MX6UL_PAD_ENET2_RX_DATA0__GPIO2_IO08    0x10b0 /* OTG1 PWR */
 
MX6UL_PAD_ENET2_RX_DATA1__GPIO2_IO09    0x17059 /* OTG1_OC */
 
>;
 
};
 
 
pinctrl_usb_otg1_oc: usbotg1grp1 {
 
fsl,pins = <
 
MX6UL_PAD_ENET2_RX_DATA0__GPIO2_IO08    0x10b0 /* OTG1 PWR */
 
MX6UL_PAD_ENET2_RX_DATA1__USB_OTG1_OC  0x17059 /* OTG1_OC */
 
>;
 
};
 
 
pinctrl_usb_otg2: usbotg2grp {
 
fsl,pins = <
 
MX6UL_PAD_ENET2_TX_DATA1__GPIO2_IO12    0x17059 /* OTG2_PWR */
 
MX6UL_PAD_ENET2_TX_EN__USB_OTG2_OC      0x17059 /* OTG2_OC */
 
>;
 
};
 
 
pinctrl_usb_otg2_1: usbotg2grp-1 {
 
fsl,pins = <
 
MX6UL_PAD_UART3_CTS_B__GPIO1_IO26      0x17059 /* OTG2_PWR */
 
MX6UL_PAD_UART3_RTS_B__GPIO1_IO27      0x17059 /* OTG2_OC */
 
>;
 
};
 
 
 
</pre>
 
</pre>
  
From <code>imx6ul-lynx-som0013-cb002f.dts</code>:
+
and from <code>imx6ul-lynx-som0013.dtsi</code>:
  
 
<pre>
 
<pre>
&reg_usb_otg1_vbus {
 
        pinctrl-0 = <&pinctrl_usb_otg1_oc>;
 
};
 
 
&usbotg1 {
 
        over-current-active-low;
 
        status = "okay";
 
};
 
 
&usbotg2 {
 
        over-current-active-low;
 
        status = "okay";
 
};
 
 
...
 
...
 
&iomuxc {
 
        pinctrl-names = "default";
 
        pinctrl-0 = <&pinctrl_hog_gpios>;
 
  
        imx6ul-lynx {
+
pinctrl_usb_otg2: usbotg2grp {
...
+
fsl,pins = <
...
+
MX6UL_PAD_ENET2_TX_DATA1__GPIO2_IO12   0x17059 /* OTG2_PWR */
                pinctrl_usb_otg1: usbotg1grp {
+
MX6UL_PAD_ENET2_TX_EN__USB_OTG2_OC      0x17059 /* OTG2_OC */
                        fsl,pins = <
+
>;
                                MX6UL_PAD_ENET2_RX_DATA0__GPIO2_IO08   0x10b0 /* OTG1 PWR */
+
};
                                MX6UL_PAD_ENET2_RX_DATA1__USB_OTG1_OC  0x17059 /* OTG1_OC */
 
                        >;
 
                };
 
  
                pinctrl_usb_otg2: usbotg2grp {
+
pinctrl_usb_otg2_1: usbotg2grp-1 {
                        fsl,pins = <
+
fsl,pins = <
                                MX6UL_PAD_ENET2_TX_DATA1__GPIO2_IO12    0x17059 /* OTG2_PWR */
+
MX6UL_PAD_UART3_CTS_B__GPIO1_IO26 0x17059 /* OTG2_PWR */
                                MX6UL_PAD_ENET2_TX_EN__USB_OTG2_OC      0x17059 /* OTG2_OC */
+
MX6UL_PAD_UART3_RTS_B__GPIO1_IO27 0x17059 /* OTG2_OC */
                        >;
+
>;
                };
+
};
  
 
</pre>
 
</pre>
 
  
 
===Accessing the peripheral===
 
===Accessing the peripheral===
Line 133: Line 68:
 
...
 
...
 
...
 
...
[    3.387128] usb_otg1_vbus: supplied by SWBST
+
[    3.458609] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 5.15
[    3.418986] usb_otg2_vbus: supplied by SWBST
+
[    3.467126] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[    5.245408] usb_otg1_vbus: disabling
+
[    3.474528] usb usb1: Product: EHCI Host Controller
 +
[    3.479474] usb usb1: Manufacturer: Linux 5.15.71-desk-mx6ul-l-4.0.0-rc1+gb3b0d0fd0042 ehci_hcd
 +
[    3.488899] usb usb1: SerialNumber: ci_hdrc.1
 
...
 
...
 
...
 
...
Line 145: Line 82:
  
 
<pre class="workstation-terminal">
 
<pre class="workstation-terminal">
root@desk-mx6ul-axelulite:~# [ 431.623145] usb 1-1: new high-speed USB device number 2 using ci_hdrc
+
[   94.701909] usb 1-1: new high-speed USB device number 2 using ci_hdrc
[ 431.865699] usb 1-1: New USB device found, idVendor=0951, idProduct=1665
+
[   94.910476] usb 1-1: New USB device found, idVendor=13fe, idProduct=6700, bcdDevice= 1.10
[ 431.872537] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
+
[   94.910584] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 431.883302] usb 1-1: Product: DataTraveler 2.0
+
[   94.910651] usb 1-1: Product: USB DISK 3.0
[ 431.887825] usb 1-1: Manufacturer: Kingston
+
[   94.910695] usb 1-1: Manufacturer: Wilk
[ 431.892114] usb 1-1: SerialNumber: 50E549C202681071F97202CB
+
[   94.910741] usb 1-1: SerialNumber: 07012533C2BE5935
[ 431.910893] usb-storage 1-1:1.0: USB Mass Storage device detected
+
[   94.932930] usb-storage 1-1:1.0: USB Mass Storage device detected
[ 431.928942] scsi host0: usb-storage 1-1:1.0
+
[   94.941189] scsi host0: usb-storage 1-1:1.0
[ 432.966408] scsi 0:0:0:0: Direct-Access    Kingston DataTraveler 2.0 0000 PQ: 0 ANSI: 4
+
[   96.015256] scsi 0:0:0:0: Direct-Access    Wilk    USB DISK 3.0     PMAP PQ: 0 ANSI: 6
[ 432.995263] sd 0:0:0:0: [sda] 15151168 512-byte logical blocks: (7.76 GB/7.22 GiB)
+
[   96.025192] sd 0:0:0:0: [sda] 60628992 512-byte logical blocks: (31.0 GB/28.9 GiB)
[ 433.015350] sd 0:0:0:0: [sda] Write Protect is off
+
[   96.026459] sd 0:0:0:0: [sda] Write Protect is off
[ 433.031915] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
+
[   96.026506] sd 0:0:0:0: [sda] Mode Sense: 45 00 00 00
[ 433.067380]  sda: sda1
+
[  96.027841] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[ 433.089246] sd 0:0:0:0: [sda] Attached SCSI removable disk
+
[   96.093511]  sda: sda1 sda2
 
+
[   96.105339] sd 0:0:0:0: [sda] Attached SCSI removable disk
root@desk-mx6ul-axelulite:~#
 
 
</pre>
 
</pre>
  
Line 166: Line 102:
  
 
<pre class="workstation-terminal">
 
<pre class="workstation-terminal">
root@desk-mx6ul-axelulite:~# dd if=/dev/zero of=mass_storage count=32 bs=1M
+
root@desk-mx6ul-lynx:~# dd if=/dev/zero of=mass_storage count=32 bs=1M  
 
32+0 records in
 
32+0 records in
 
32+0 records out
 
32+0 records out
33554432 bytes (34 MB, 32 MiB) copied, 3.62181 s, 9.3 MB/s
+
33554432 bytes (34 MB, 32 MiB) copied, 0.573118 s, 58.5 MB/s
root@desk-mx6ul-axelulite:~# mkfs.msdos mass_storage
+
root@desk-mx6ul-lynx:~# mkfs.msdos mass_storage
mkfs.fat 4.1 (2017-01-24)
+
mkfs.fat 4.2 (2021-01-31)
root@desk-mx6ul-axelulite:~# mkdir loop
+
root@desk-mx6ul-lynx:~# mkdir loop
root@desk-mx6ul-axelulite:~# mount -o loop mass_storage loop
+
root@desk-mx6ul-lynx:~# mount -o loop mass_storage loop
root@desk-mx6ul-axelulite:~# echo "Test USB OTG with mass storage device" > loop/usb.txt
+
root@desk-mx6ul-lynx:~# echo "Test USB OTG with mass storage device" > loop/usb.txt
root@desk-mx6ul-axelulite:~# umount loop
+
root@desk-mx6ul-lynx:~# umount loop/
 
</pre>
 
</pre>
  
Line 181: Line 117:
  
 
<pre class="workstation-terminal">
 
<pre class="workstation-terminal">
root@desk-mx6ul-axelulite:~# modprobe g_mass_storage removable=y file=mass_storage
+
root@desk-mx6ul-lynx:~# modprobe g_mass_storage removable=y file=mass_storage
137.706620] Mass Storage Function, version: 2009/09/11
+
root@desk-mx6ul-lynx:~# dmesg | tail -n 7
137.711809] LUN: removable file: (no medium)
+
166.355438] Mass Storage Function, version: 2009/09/11
137.731390] LUN: removable file: /home/root/mass_storage
+
166.355484] LUN: removable file: (no medium)
137.737101] Number of LUNs=1
+
166.355723] LUN: removable file: /home/root/mass_storage
137.740256] g_mass_storage gadget: Mass Storage Gadget, version: 2009/09/11
+
166.355748] Number of LUNs=1
137.751272] g_mass_storage gadget: userspace failed to provide iSerialNumber
+
166.365515] g_mass_storage gadget: Mass Storage Gadget, version: 2009/09/11
137.760299] g_mass_storage gadget: g_mass_storage ready
+
166.365556] g_mass_storage gadget: userspace failed to provide iSerialNumber
root@desk-mx6ul-axelulite:~#
+
166.365572] g_mass_storage gadget: g_mass_storage ready
 
</pre>
 
</pre>
  
Once the USB cable is connected to the PC, the kernel prints the following messages:
+
Once the USB cable is connected to the PC, the storage is mounted and the ''usb.txt'' file is available:
  
 
<pre class="workstation-terminal">
 
<pre class="workstation-terminal">
root@desk-mx6ul-axelulite:~# [  214.837430] g_mass_storage gadget: high-speed config #1: Linux File-Backed Storage
+
$ cat /media/tomzy/42D5-CBA5/usb.txt
 +
Test USB OTG with mass storage device
 
</pre>
 
</pre>
  
and the Windows PC activate the driver and the disk is available as a Drive Unit (with the ''usb.txt'' file available).
+
The Windows PC also activate the driver and the disk is available as a Drive Unit (with the ''usb.txt'' file available).
  
 
=== Additional information ===
 
=== Additional information ===
  
More information about Mass Storage Gadget driver is given in the kernel tree under ''Documentation/usb/mass-storage.txt''
+
More information about Mass Storage Gadget driver is given in the kernel tree under ''Documentation/usb/mass-storage.rst''
  
<section end=Body/>
+
<section end="Body" />
  
 
----
 
----
  
 
[[Category:AXEL ULite]]
 
[[Category:AXEL ULite]]

Latest revision as of 18:03, 11 January 2024

History
Issue Date Notes

2021/07/20

First DESK-MX6UL-L release

2022/03/16

DESK-MX6UL-L 3.0.0 release
2023/05/04 DESK-MX6UL-L 4.0.0 release


Peripheral USB OTG[edit | edit source]

The USB OTG ports can be configured as Host or Device mode depending on the device tree configuration. In OTG mode they can be easily tested using the Mass Storage Gadget, which lets the device export a file as a mass storage device to the connected PC.


200px-Emblem-important.svg.png

The USB OTG peripheral is not available - as default option - on AXEL ULite EVK. Please contact Sales department for this option.
This peripheral is available on the i.MX6UL standard product SBCLynx

Device tree configuration[edit | edit source]

Here below an example of device tree configuration used on standard DAVE's kit for the AXEL ULite SOM where USB OTG1 is configured as otg while the USB OTG2 port is configured in host mode:

From imx6ul-lynx-som0013-cb002f.dts:

		pinctrl_usb_otg2: usbotg2grp {
			fsl,pins = <
				MX6UL_PAD_ENET2_TX_DATA1__GPIO2_IO12    0x17059 /* OTG2_PWR */
				MX6UL_PAD_ENET2_TX_EN__USB_OTG2_OC       0x17059 /* OTG2_OC */
			>;
		};
	};
};

and from imx6ul-lynx-som0013.dtsi:


		pinctrl_usb_otg2: usbotg2grp {
			fsl,pins = <
				MX6UL_PAD_ENET2_TX_DATA1__GPIO2_IO12    0x17059 /* OTG2_PWR */
				MX6UL_PAD_ENET2_TX_EN__USB_OTG2_OC       0x17059 /* OTG2_OC */
			>;
		};

		pinctrl_usb_otg2_1: usbotg2grp-1 {
			fsl,pins = <
				MX6UL_PAD_UART3_CTS_B__GPIO1_IO26	0x17059 /* OTG2_PWR */
				MX6UL_PAD_UART3_RTS_B__GPIO1_IO27	0x17059 /* OTG2_OC */
			>;
		};

Accessing the peripheral[edit | edit source]

Linux messages at boot time[edit | edit source]

...
...
[    3.458609] usb usb1: New USB device found, idVendor=1d6b, idProduct=0002, bcdDevice= 5.15
[    3.467126] usb usb1: New USB device strings: Mfr=3, Product=2, SerialNumber=1
[    3.474528] usb usb1: Product: EHCI Host Controller
[    3.479474] usb usb1: Manufacturer: Linux 5.15.71-desk-mx6ul-l-4.0.0-rc1+gb3b0d0fd0042 ehci_hcd
[    3.488899] usb usb1: SerialNumber: ci_hdrc.1
...
...

Usage in Host mode[edit | edit source]

When a USB peripheral is inserted, in the following example a memory mass storage device, the kernel recognizes the device (i.e. class, vendor id, product id, etc.)

[   94.701909] usb 1-1: new high-speed USB device number 2 using ci_hdrc
[   94.910476] usb 1-1: New USB device found, idVendor=13fe, idProduct=6700, bcdDevice= 1.10
[   94.910584] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[   94.910651] usb 1-1: Product: USB DISK 3.0
[   94.910695] usb 1-1: Manufacturer: Wilk
[   94.910741] usb 1-1: SerialNumber: 07012533C2BE5935
[   94.932930] usb-storage 1-1:1.0: USB Mass Storage device detected
[   94.941189] scsi host0: usb-storage 1-1:1.0
[   96.015256] scsi 0:0:0:0: Direct-Access     Wilk     USB DISK 3.0     PMAP PQ: 0 ANSI: 6
[   96.025192] sd 0:0:0:0: [sda] 60628992 512-byte logical blocks: (31.0 GB/28.9 GiB)
[   96.026459] sd 0:0:0:0: [sda] Write Protect is off
[   96.026506] sd 0:0:0:0: [sda] Mode Sense: 45 00 00 00
[   96.027841] sd 0:0:0:0: [sda] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[   96.093511]  sda: sda1 sda2
[   96.105339] sd 0:0:0:0: [sda] Attached SCSI removable disk

Usage with mass-storage[edit | edit source]

root@desk-mx6ul-lynx:~# dd if=/dev/zero of=mass_storage count=32 bs=1M   
32+0 records in
32+0 records out
33554432 bytes (34 MB, 32 MiB) copied, 0.573118 s, 58.5 MB/s
root@desk-mx6ul-lynx:~# mkfs.msdos mass_storage
mkfs.fat 4.2 (2021-01-31)
root@desk-mx6ul-lynx:~# mkdir loop
root@desk-mx6ul-lynx:~# mount -o loop mass_storage loop
root@desk-mx6ul-lynx:~# echo "Test USB OTG with mass storage device" > loop/usb.txt
root@desk-mx6ul-lynx:~# umount loop/

then insert the g_mass_storage kernel module driver enabling an Windows PC to see it as a removable device

root@desk-mx6ul-lynx:~# modprobe g_mass_storage removable=y file=mass_storage
root@desk-mx6ul-lynx:~# dmesg | tail -n 7
[  166.355438] Mass Storage Function, version: 2009/09/11
[  166.355484] LUN: removable file: (no medium)
[  166.355723] LUN: removable file: /home/root/mass_storage
[  166.355748] Number of LUNs=1
[  166.365515] g_mass_storage gadget: Mass Storage Gadget, version: 2009/09/11
[  166.365556] g_mass_storage gadget: userspace failed to provide iSerialNumber
[  166.365572] g_mass_storage gadget: g_mass_storage ready

Once the USB cable is connected to the PC, the storage is mounted and the usb.txt file is available:

$ cat /media/tomzy/42D5-CBA5/usb.txt 
Test USB OTG with mass storage device

The Windows PC also activate the driver and the disk is available as a Drive Unit (with the usb.txt file available).

Additional information[edit | edit source]

More information about Mass Storage Gadget driver is given in the kernel tree under Documentation/usb/mass-storage.rst