| Message ID | 20200216172117.49832-1-noralf@tronnes.org (mailing list archive) |
|---|---|
| Headers | show |
| Series | Regmap over USB for Multifunction USB Device (gpio, display, ...) | expand |
On Sun, Feb 16, 2020 at 06:21:08PM +0100, Noralf Trønnes wrote: > Hi, > > A while back I had the idea to turn a Raspberry Pi Zero into a $5 > USB to HDMI/SDTV/DSI/DPI display adapter. > > Thinking about how to represent the display to the driver I realised > that hardware use registers as API. And Linux does have a generic > register abstraction: regmap. Furthermore this means that if I can do a > regmap over USB implementation, it will be easy to do other functions > like gpio, adc and others. After a few iterations trying to understand > the USB subsystem and satisfying driver requirements, I now have > something that looks promising. > > I'm sending out an early version hoping to get feedback especially on > the core parts that handles regmap and interrupts. > > Overview: > > USB Host : USB Device > : > -------------- : ------------------ > ---------- | mfd: mud | : | f_mud | ---------- > | Driver | -------------- : | | | Driver | > ---------- | regmap-usb | : | (mud_regmap) | ---------- > -------------- : ------------------ > > > I've attached 2 drivers: > - gpio/pinctrl: is more or less finished > - display: needs a lot more work > > > USB3 device > I've only tested this with usb2 devices (Pi, BBB) so I should get myself > a usb3 gadget capable board. My searching didn't turn up much, so this > seems to be quite rare. ROCK960 has USB 3.0 type C OTG but the price is > $139 which is a bit expensive for this hobby project. Does anyone know > of a cheap board? > > Noralf. Pretty cool idea, and the drm side looks really tiny (after all your drm_client work that is). I think the important feedback here is for the usb and regmap stuff, that's totally out of my area. I've commented on the drm_client patch, but that's just minor stuff, imo looks good. Cheers, Daniel > > > Noralf Trønnes (9): > regmap: Add USB support > mfd: Add driver for Multifunction USB Device > usb: gadget: function: Add Multifunction USB Device support > pinctrl: Add Multifunction USB Device pinctrl driver > usb: gadget: function: mud: Add gpio support > regmap: Speed up _regmap_raw_write_impl() for large buffers > drm: Add Multifunction USB Device display driver > drm/client: Add drm_client_init_from_id() and drm_client_modeset_set() > usb: gadget: function: mud: Add display support > > drivers/base/regmap/Kconfig | 8 +- > drivers/base/regmap/Makefile | 1 + > drivers/base/regmap/regmap-usb.c | 1026 ++++++++++++++++++ > drivers/base/regmap/regmap.c | 10 +- > drivers/gpu/drm/Kconfig | 2 + > drivers/gpu/drm/Makefile | 1 + > drivers/gpu/drm/drm_client.c | 37 + > drivers/gpu/drm/drm_client_modeset.c | 52 + > drivers/gpu/drm/mud/Kconfig | 18 + > drivers/gpu/drm/mud/Makefile | 4 + > drivers/gpu/drm/mud/mud_drm.c | 1198 ++++++++++++++++++++++ > drivers/gpu/drm/mud/mud_drm.h | 137 +++ > drivers/gpu/drm/mud/mud_drm_gadget.c | 889 ++++++++++++++++ > drivers/mfd/Kconfig | 8 + > drivers/mfd/Makefile | 1 + > drivers/mfd/mud.c | 580 +++++++++++ > drivers/pinctrl/Kconfig | 9 + > drivers/pinctrl/Makefile | 1 + > drivers/pinctrl/pinctrl-mud.c | 657 ++++++++++++ > drivers/pinctrl/pinctrl-mud.h | 89 ++ > drivers/usb/gadget/Kconfig | 36 + > drivers/usb/gadget/function/Makefile | 6 + > drivers/usb/gadget/function/f_mud.c | 913 +++++++++++++++++ > drivers/usb/gadget/function/f_mud.h | 210 ++++ > drivers/usb/gadget/function/f_mud_drm.c | 181 ++++ > drivers/usb/gadget/function/f_mud_pins.c | 962 +++++++++++++++++ > drivers/usb/gadget/function/mud_regmap.c | 936 +++++++++++++++++ > include/drm/drm_client.h | 4 + > include/linux/mfd/mud.h | 16 + > include/linux/regmap.h | 23 + > include/linux/regmap_usb.h | 97 ++ > 31 files changed, 8107 insertions(+), 5 deletions(-) > create mode 100644 drivers/base/regmap/regmap-usb.c > create mode 100644 drivers/gpu/drm/mud/Kconfig > create mode 100644 drivers/gpu/drm/mud/Makefile > create mode 100644 drivers/gpu/drm/mud/mud_drm.c > create mode 100644 drivers/gpu/drm/mud/mud_drm.h > create mode 100644 drivers/gpu/drm/mud/mud_drm_gadget.c > create mode 100644 drivers/mfd/mud.c > create mode 100644 drivers/pinctrl/pinctrl-mud.c > create mode 100644 drivers/pinctrl/pinctrl-mud.h > create mode 100644 drivers/usb/gadget/function/f_mud.c > create mode 100644 drivers/usb/gadget/function/f_mud.h > create mode 100644 drivers/usb/gadget/function/f_mud_drm.c > create mode 100644 drivers/usb/gadget/function/f_mud_pins.c > create mode 100644 drivers/usb/gadget/function/mud_regmap.c > create mode 100644 include/linux/mfd/mud.h > create mode 100644 include/linux/regmap_usb.h > > -- > 2.23.0 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
Hi, On 16/02/2020 18:21, Noralf Trønnes wrote: > Hi, > > A while back I had the idea to turn a Raspberry Pi Zero into a $5 > USB to HDMI/SDTV/DSI/DPI display adapter. > > Thinking about how to represent the display to the driver I realised > that hardware use registers as API. And Linux does have a generic > register abstraction: regmap. Furthermore this means that if I can do a > regmap over USB implementation, it will be easy to do other functions > like gpio, adc and others. After a few iterations trying to understand > the USB subsystem and satisfying driver requirements, I now have > something that looks promising. > > I'm sending out an early version hoping to get feedback especially on > the core parts that handles regmap and interrupts. > > Overview: > > USB Host : USB Device > : > -------------- : ------------------ > ---------- | mfd: mud | : | f_mud | ---------- > | Driver | -------------- : | | | Driver | > ---------- | regmap-usb | : | (mud_regmap) | ---------- > -------------- : ------------------ > The idea is really like ARA's greybus, but much simpler ! Anyway nice idea, do you have good performance over USB2 and RPi's awful DWC2 gagdet controller ? Neil > > I've attached 2 drivers: > - gpio/pinctrl: is more or less finished > - display: needs a lot more work > > > USB3 device > I've only tested this with usb2 devices (Pi, BBB) so I should get myself > a usb3 gadget capable board. My searching didn't turn up much, so this > seems to be quite rare. ROCK960 has USB 3.0 type C OTG but the price is > $139 which is a bit expensive for this hobby project. Does anyone know > of a cheap board? > > Noralf. > > > Noralf Trønnes (9): > regmap: Add USB support > mfd: Add driver for Multifunction USB Device > usb: gadget: function: Add Multifunction USB Device support > pinctrl: Add Multifunction USB Device pinctrl driver > usb: gadget: function: mud: Add gpio support > regmap: Speed up _regmap_raw_write_impl() for large buffers > drm: Add Multifunction USB Device display driver > drm/client: Add drm_client_init_from_id() and drm_client_modeset_set() > usb: gadget: function: mud: Add display support > > drivers/base/regmap/Kconfig | 8 +- > drivers/base/regmap/Makefile | 1 + > drivers/base/regmap/regmap-usb.c | 1026 ++++++++++++++++++ > drivers/base/regmap/regmap.c | 10 +- > drivers/gpu/drm/Kconfig | 2 + > drivers/gpu/drm/Makefile | 1 + > drivers/gpu/drm/drm_client.c | 37 + > drivers/gpu/drm/drm_client_modeset.c | 52 + > drivers/gpu/drm/mud/Kconfig | 18 + > drivers/gpu/drm/mud/Makefile | 4 + > drivers/gpu/drm/mud/mud_drm.c | 1198 ++++++++++++++++++++++ > drivers/gpu/drm/mud/mud_drm.h | 137 +++ > drivers/gpu/drm/mud/mud_drm_gadget.c | 889 ++++++++++++++++ > drivers/mfd/Kconfig | 8 + > drivers/mfd/Makefile | 1 + > drivers/mfd/mud.c | 580 +++++++++++ > drivers/pinctrl/Kconfig | 9 + > drivers/pinctrl/Makefile | 1 + > drivers/pinctrl/pinctrl-mud.c | 657 ++++++++++++ > drivers/pinctrl/pinctrl-mud.h | 89 ++ > drivers/usb/gadget/Kconfig | 36 + > drivers/usb/gadget/function/Makefile | 6 + > drivers/usb/gadget/function/f_mud.c | 913 +++++++++++++++++ > drivers/usb/gadget/function/f_mud.h | 210 ++++ > drivers/usb/gadget/function/f_mud_drm.c | 181 ++++ > drivers/usb/gadget/function/f_mud_pins.c | 962 +++++++++++++++++ > drivers/usb/gadget/function/mud_regmap.c | 936 +++++++++++++++++ > include/drm/drm_client.h | 4 + > include/linux/mfd/mud.h | 16 + > include/linux/regmap.h | 23 + > include/linux/regmap_usb.h | 97 ++ > 31 files changed, 8107 insertions(+), 5 deletions(-) > create mode 100644 drivers/base/regmap/regmap-usb.c > create mode 100644 drivers/gpu/drm/mud/Kconfig > create mode 100644 drivers/gpu/drm/mud/Makefile > create mode 100644 drivers/gpu/drm/mud/mud_drm.c > create mode 100644 drivers/gpu/drm/mud/mud_drm.h > create mode 100644 drivers/gpu/drm/mud/mud_drm_gadget.c > create mode 100644 drivers/mfd/mud.c > create mode 100644 drivers/pinctrl/pinctrl-mud.c > create mode 100644 drivers/pinctrl/pinctrl-mud.h > create mode 100644 drivers/usb/gadget/function/f_mud.c > create mode 100644 drivers/usb/gadget/function/f_mud.h > create mode 100644 drivers/usb/gadget/function/f_mud_drm.c > create mode 100644 drivers/usb/gadget/function/f_mud_pins.c > create mode 100644 drivers/usb/gadget/function/mud_regmap.c > create mode 100644 include/linux/mfd/mud.h > create mode 100644 include/linux/regmap_usb.h >
Den 17.02.2020 11.32, skrev Neil Armstrong: > Hi, > > On 16/02/2020 18:21, Noralf Trønnes wrote: >> Hi, >> >> A while back I had the idea to turn a Raspberry Pi Zero into a $5 >> USB to HDMI/SDTV/DSI/DPI display adapter. >> >> Thinking about how to represent the display to the driver I realised >> that hardware use registers as API. And Linux does have a generic >> register abstraction: regmap. Furthermore this means that if I can do a >> regmap over USB implementation, it will be easy to do other functions >> like gpio, adc and others. After a few iterations trying to understand >> the USB subsystem and satisfying driver requirements, I now have >> something that looks promising. >> >> I'm sending out an early version hoping to get feedback especially on >> the core parts that handles regmap and interrupts. >> >> Overview: >> >> USB Host : USB Device >> : >> -------------- : ------------------ >> ---------- | mfd: mud | : | f_mud | ---------- >> | Driver | -------------- : | | | Driver | >> ---------- | regmap-usb | : | (mud_regmap) | ---------- >> -------------- : ------------------ >> > > The idea is really like ARA's greybus, but much simpler ! > Anyway nice idea, do you have good performance over USB2 and > RPi's awful DWC2 gagdet controller ? > Not as good as I was hoping for. If I disable compression I'm getting 5 fps for a 1.5MB framebuffer (7800 kB/s): $ modetest -M mud_drm -s 35:1024x768@RG16 -v setting mode 1024x768-60.00Hz@RG16 on connectors 35, crtc 33 freq: 5.07Hz When I tried reading I discovered that it was almost 3 times faster than writing. The zero gadget (loop testing) confirmed my findings: Device: $ sudo modprobe g_zero [ 44.221890] zero gadget: Gadget Zero, version: Cinco de Mayo 2008 [ 44.221906] zero gadget: zero ready [ 60.751451] zero gadget: high-speed config #3: source/sink Host: $ sudo ~/testusb -a -t <n> -g 64 -s 16384 /dev/bus/usb/001/010 test 27, 107.230669 secs -> 1000 / 107 = 9MB/s /dev/bus/usb/001/010 test 28, 37.791292 secs -> 1000 / 37 = 27MB/s [73983.796552] usbtest 1-1.3:3.0: TEST 27: bulk write 1000Mbytes [74205.060204] usbtest 1-1.3:3.0: TEST 28: bulk read 1000Mbytes $ sudo ~/testusb -a -t <n> -g 64 -s 16384 /dev/bus/usb/001/010 test 5, 107.421535 secs /dev/bus/usb/001/010 test 6, 38.189712 secs [74893.204170] usbtest 1-1.3:3.0: TEST 5: write 1000 sglists 64 entries of 16384 bytes [75012.592222] usbtest 1-1.3:3.0: TEST 6: read 1000 sglists 64 entries of 16384 bytes I have tried Raspberry Pi1 and Pi4 as host (2 different controllers) and Pi Zero and Beaglebone Black as device, getting similar result. I found this post having the same issue: Re: Asymmetric speed results with testusb/usbtest/g_zero https://www.spinics.net/lists/linux-usb/msg100588.html I haven't got a usb analyzer, but adding printk to dwc2_assign_and_init_hc() showed that IN interrupts were 2-3 ms apart but OUT interrupts were ~8 ms apart. Noralf.
On Sun, Feb 16, 2020 at 7:30 PM Noralf Trønnes <noralf@tronnes.org> wrote: > > Hi, > > A while back I had the idea to turn a Raspberry Pi Zero into a $5 > USB to HDMI/SDTV/DSI/DPI display adapter. > > Thinking about how to represent the display to the driver I realised > that hardware use registers as API. And Linux does have a generic > register abstraction: regmap. Furthermore this means that if I can do a > regmap over USB implementation, it will be easy to do other functions > like gpio, adc and others. After a few iterations trying to understand > the USB subsystem and satisfying driver requirements, I now have > something that looks promising. > > I'm sending out an early version hoping to get feedback especially on > the core parts that handles regmap and interrupts. > > Overview: > > USB Host : USB Device > : > -------------- : ------------------ > ---------- | mfd: mud | : | f_mud | ---------- > | Driver | -------------- : | | | Driver | > ---------- | regmap-usb | : | (mud_regmap) | ---------- > -------------- : ------------------ > > > I've attached 2 drivers: > - gpio/pinctrl: is more or less finished > - display: needs a lot more work Can regmap-usb be used for drivers/mfd/dln2.c for example?
Den 18.02.2020 21.57, skrev Andy Shevchenko: > On Sun, Feb 16, 2020 at 7:30 PM Noralf Trønnes <noralf@tronnes.org> wrote: >> >> Hi, >> >> A while back I had the idea to turn a Raspberry Pi Zero into a $5 >> USB to HDMI/SDTV/DSI/DPI display adapter. >> >> Thinking about how to represent the display to the driver I realised >> that hardware use registers as API. And Linux does have a generic >> register abstraction: regmap. Furthermore this means that if I can do a >> regmap over USB implementation, it will be easy to do other functions >> like gpio, adc and others. After a few iterations trying to understand >> the USB subsystem and satisfying driver requirements, I now have >> something that looks promising. >> >> I'm sending out an early version hoping to get feedback especially on >> the core parts that handles regmap and interrupts. >> >> Overview: >> >> USB Host : USB Device >> : >> -------------- : ------------------ >> ---------- | mfd: mud | : | f_mud | ---------- >> | Driver | -------------- : | | | Driver | >> ---------- | regmap-usb | : | (mud_regmap) | ---------- >> -------------- : ------------------ >> >> >> I've attached 2 drivers: >> - gpio/pinctrl: is more or less finished >> - display: needs a lot more work > > Can regmap-usb be used for drivers/mfd/dln2.c for example? > No, apparently dln-2 uses custom protocol structs for each function with a common header. regmap-usb is a register abstraction with the ability to bulk read/write multiple registers in one transfer. I see that dln-2 does a lot of what I'm aiming for except that it doesn't have the display part. Noralf.
Hi, A while back I had the idea to turn a Raspberry Pi Zero into a $5 USB to HDMI/SDTV/DSI/DPI display adapter. Thinking about how to represent the display to the driver I realised that hardware use registers as API. And Linux does have a generic register abstraction: regmap. Furthermore this means that if I can do a regmap over USB implementation, it will be easy to do other functions like gpio, adc and others. After a few iterations trying to understand the USB subsystem and satisfying driver requirements, I now have something that looks promising. I'm sending out an early version hoping to get feedback especially on the core parts that handles regmap and interrupts. Overview: USB Host : USB Device : -------------- : ------------------ ---------- | mfd: mud | : | f_mud | ---------- | Driver | -------------- : | | | Driver | ---------- | regmap-usb | : | (mud_regmap) | ---------- -------------- : ------------------ I've attached 2 drivers: - gpio/pinctrl: is more or less finished - display: needs a lot more work USB3 device I've only tested this with usb2 devices (Pi, BBB) so I should get myself a usb3 gadget capable board. My searching didn't turn up much, so this seems to be quite rare. ROCK960 has USB 3.0 type C OTG but the price is $139 which is a bit expensive for this hobby project. Does anyone know of a cheap board? Noralf. Noralf Trønnes (9): regmap: Add USB support mfd: Add driver for Multifunction USB Device usb: gadget: function: Add Multifunction USB Device support pinctrl: Add Multifunction USB Device pinctrl driver usb: gadget: function: mud: Add gpio support regmap: Speed up _regmap_raw_write_impl() for large buffers drm: Add Multifunction USB Device display driver drm/client: Add drm_client_init_from_id() and drm_client_modeset_set() usb: gadget: function: mud: Add display support drivers/base/regmap/Kconfig | 8 +- drivers/base/regmap/Makefile | 1 + drivers/base/regmap/regmap-usb.c | 1026 ++++++++++++++++++ drivers/base/regmap/regmap.c | 10 +- drivers/gpu/drm/Kconfig | 2 + drivers/gpu/drm/Makefile | 1 + drivers/gpu/drm/drm_client.c | 37 + drivers/gpu/drm/drm_client_modeset.c | 52 + drivers/gpu/drm/mud/Kconfig | 18 + drivers/gpu/drm/mud/Makefile | 4 + drivers/gpu/drm/mud/mud_drm.c | 1198 ++++++++++++++++++++++ drivers/gpu/drm/mud/mud_drm.h | 137 +++ drivers/gpu/drm/mud/mud_drm_gadget.c | 889 ++++++++++++++++ drivers/mfd/Kconfig | 8 + drivers/mfd/Makefile | 1 + drivers/mfd/mud.c | 580 +++++++++++ drivers/pinctrl/Kconfig | 9 + drivers/pinctrl/Makefile | 1 + drivers/pinctrl/pinctrl-mud.c | 657 ++++++++++++ drivers/pinctrl/pinctrl-mud.h | 89 ++ drivers/usb/gadget/Kconfig | 36 + drivers/usb/gadget/function/Makefile | 6 + drivers/usb/gadget/function/f_mud.c | 913 +++++++++++++++++ drivers/usb/gadget/function/f_mud.h | 210 ++++ drivers/usb/gadget/function/f_mud_drm.c | 181 ++++ drivers/usb/gadget/function/f_mud_pins.c | 962 +++++++++++++++++ drivers/usb/gadget/function/mud_regmap.c | 936 +++++++++++++++++ include/drm/drm_client.h | 4 + include/linux/mfd/mud.h | 16 + include/linux/regmap.h | 23 + include/linux/regmap_usb.h | 97 ++ 31 files changed, 8107 insertions(+), 5 deletions(-) create mode 100644 drivers/base/regmap/regmap-usb.c create mode 100644 drivers/gpu/drm/mud/Kconfig create mode 100644 drivers/gpu/drm/mud/Makefile create mode 100644 drivers/gpu/drm/mud/mud_drm.c create mode 100644 drivers/gpu/drm/mud/mud_drm.h create mode 100644 drivers/gpu/drm/mud/mud_drm_gadget.c create mode 100644 drivers/mfd/mud.c create mode 100644 drivers/pinctrl/pinctrl-mud.c create mode 100644 drivers/pinctrl/pinctrl-mud.h create mode 100644 drivers/usb/gadget/function/f_mud.c create mode 100644 drivers/usb/gadget/function/f_mud.h create mode 100644 drivers/usb/gadget/function/f_mud_drm.c create mode 100644 drivers/usb/gadget/function/f_mud_pins.c create mode 100644 drivers/usb/gadget/function/mud_regmap.c create mode 100644 include/linux/mfd/mud.h create mode 100644 include/linux/regmap_usb.h