Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 96 insertions, 0 deletions

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+1. How to test OTG FSM(HNP and SRP)
+-----------------------------------
+To show how to demo OTG HNP and SRP functions via sys input files
+with 2 Freescale i.MX6Q sabre SD boards.
+
+1.1 How to enable OTG FSM
+---------------------------------------
+1.1.1 Select CONFIG_USB_OTG_FSM in menuconfig, rebuild kernel
+Image and modules. If you want to check some internal
+variables for otg fsm, mount debugfs, there are 2 files
+which can show otg fsm variables and some controller registers value:
+cat /sys/kernel/debug/ci_hdrc.0/otg
+cat /sys/kernel/debug/ci_hdrc.0/registers
+1.1.2 Add below entries in your dts file for your controller node
+	otg-rev = <0x0200>;
+	adp-disable;
+
+1.2 Test operations
+-------------------
+1) Power up 2 Freescale i.MX6Q sabre SD boards with gadget class driver loaded
+   (e.g. g_mass_storage).
+
+2) Connect 2 boards with usb cable with one end is micro A plug, the other end
+   is micro B plug.
+
+   The A-device(with micro A plug inserted) should enumerate B-device.
+
+3) Role switch
+   On B-device:
+   echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+   B-device should take host role and enumerate A-device.
+
+4) A-device switch back to host.
+   On B-device:
+   echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+   or, by introducing HNP polling, B-Host can know when A-peripheral wish
+   to be host role, so this role switch also can be trigged in A-peripheral
+   side by answering the polling from B-Host, this can be done on A-device:
+   echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req
+
+   A-device should switch back to host and enumerate B-device.
+
+5) Remove B-device(unplug micro B plug) and insert again in 10 seconds,
+   A-device should enumerate B-device again.
+
+6) Remove B-device(unplug micro B plug) and insert again after 10 seconds,
+   A-device should NOT enumerate B-device.
+
+   if A-device wants to use bus:
+   On A-device:
+   echo 0 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop
+   echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_req
+
+   if B-device wants to use bus:
+   On B-device:
+   echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+7) A-device power down the bus.
+   On A-device:
+   echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/a_bus_drop
+
+   A-device should disconnect with B-device and power down the bus.
+
+8) B-device does data pulse for SRP.
+   On B-device:
+   echo 1 > /sys/bus/platform/devices/ci_hdrc.0/inputs/b_bus_req
+
+   A-device should resume usb bus and enumerate B-device.
+
+1.3 Reference document
+----------------------
+"On-The-Go and Embedded Host Supplement to the USB Revision 2.0 Specification
+July 27, 2012 Revision 2.0 version 1.1a"
+
+2. How to enable USB as system wakeup source
+-----------------------------------
+Below is the example for how to enable USB as system wakeup source
+at imx6 platform.
+
+2.1 Enable core's wakeup
+echo enabled > /sys/bus/platform/devices/ci_hdrc.0/power/wakeup
+2.2 Enable glue layer's wakeup
+echo enabled > /sys/bus/platform/devices/2184000.usb/power/wakeup
+2.3 Enable PHY's wakeup (optional)
+echo enabled > /sys/bus/platform/devices/20c9000.usbphy/power/wakeup
+2.4 Enable roothub's wakeup
+echo enabled > /sys/bus/usb/devices/usb1/power/wakeup
+2.5 Enable related device's wakeup
+echo enabled > /sys/bus/usb/devices/1-1/power/wakeup
+
+If the system has only one usb port, and you want usb wakeup at this port, you
+can use below script to enable usb wakeup.
+for i in $(find /sys -name wakeup | grep usb);do echo enabled > $i;done;
+