This adds a new driver for the USB3 PHY found on Meson GXL and GXM SoCs
(both SoCs are using the same USB PHY register layout).
Unfortunately there is no documentation for this PHY in the public S905X
datasheet (published for example by Khadas). What we know so far about
this PHY:
- even though the Meson GXL and GXM SoCs do not expose an USB3 port (the
dwc3 controller only has USB2 ports enabled) we need to initialize the
USB3 PHY (specifically USB_R1_U3H_FLADJ_30MHZ_REG_MASK). Without this
initialization high-speed USB devices (especially USB hard disks and
thumb drives, slower devices like mice do not seem to be affected)
- on some boards the USB3 PHY starts in "device mode" - we want to bring
it into a known state (by switching it to host mode for now).
- it is responsible for the OTG detection and for switching the first
USB2 PHY between host and peripheral (aka device) mode. an interrupt
can be used to detect changes between host and device mode.
There are five inputs to this register area:
- the clock and reset line for the USB3 PHY itself
- the clock and reset line for the peripheral mode and OTG detection
logic (on the GXL and GXM SoCs these are the same clock and reset line
as for the USB3 PHY itself, but Amlogic sees this as two different
components - even though they share the same register space - so they
have to be passed individually to allow specifying different inputs on
other SoCs if needed)
- the interrupt for the OTG detection logic
The whole OTG detection logic is not implemented yet.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Yixun Lan <yixun.lan@amlogic.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
The U2P_R2 register provides "test mode" functionality for bits 17:0.
These are only used during SoC development and should be left untouched
on production SoC versions.
Rename these register definitions to indicate that these are for "test
mode" only.
While here, also merge the definitions for U2P_R2_DATA_IN_MASK and
U2P_R2_DATA_IN_EN_MASK (bits 0:7) because Amlogic's internal
documentation suggests that these bits belong together. The old
definition was not taken from the documentation but rather from a struct
definition in the Amlogic GPL kernel sources.
No functional changes.
Suggested-by: Yixun Lan <yixun.lan@amlogic.com>
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
The USB2 PHY can switch between PHY_MODE_USB_HOST and
PHY_MODE_USB_DEVICE. However, it cannot do it on it's own since it
requires re-routing of the corresponding USB pins from dwc3 (which is
used for host-mode) to dwc2 (which is used for device-mode).
Thus we don't need to auto-detect the mode based on the USB controller,
which simplifies the driver code.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
The Meson GXL USB2 PHYs require an additional clock (USB) which has to
be enabled. If that clock is disabled then all PHY registers read 0x0.
Luckily for us that clock is always enabled (either by harddware
defaults, the bootrom, or any of the bootloaders before u-boot/BL3-3).
The OTG capable USB2 PHY additionally has a reset line (USB_OTG, which
is shared with other components, such as the USB3 PHY for example).
Extend the driver so it handles this clock and the shared reset line.
We only trigger the reset during the .init phase since it's a shared
reset line, so triggering it during the driver's .reset implementation
would effectively also only trigger it once anyways.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
devm_phy_create can return -EPROBE_DEFER if the phy-supply is not ready
yet. Silence this warning as the driver framework will re-attempt
registering the PHY - this second try works without any errors. So only
log actual errors to keep the kernel log free of misleading error
messages.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Meson8 uses the same USB PHY as found on the Meson8b and GXBB SoCs. Add
a new of_device_id to indicate this. Also update the Kconfig option and
MODULE_DESCRIPTION accordingly.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
This adds a new driver for the USB2 PHYs found on Meson GXL and GXM SoCs
(both SoCs are using the same USB PHY register layout).
The USB2 PHY is a simple PHY which only has a few registers to configure
the mode (host/device) and a reset register (to enable/disable the PHY).
Unfortunately there are no datasheets available for this PHY. The driver
was written by reading the code from Amlogic's GPL kernel sources and
by analyzing the registers on an actual GXL and GXM device running the
kernel that was shipped on the boards I have.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Martin Blumenstingl
Vivek Gautam