Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1685638

Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices

Show all headers | View raw

On Tue, Jul 11, 2017 at 08:52:37AM +0200, Anatolij Gustschin wrote:
> On Mon, 10 Jul 2017 14:34:27 +0200
> Johan Hovold johan@kernel.org wrote:
> 
> >On Fri, Jul 07, 2017 at 11:53:29AM +0200, Anatolij Gustschin wrote:
> >> On Fri, 07 Jul 2017 09:48:48 +0200
> >> Bjørn Mork bjorn@mork.no wrote:
> >>   
> >> >[adding Johan on the CC list]
> >> >
> >> >Anatolij Gustschin <agust@denx.de> writes:
> >> >  
> >> >> +static struct usb_device_id ftdi_mfd_table[] = {
> >> >> +	{ USB_DEVICE(0x0403, 0x6014) },
> >> >> +	{}
> >> >> +};
> >> >> +MODULE_DEVICE_TABLE(usb, ftdi_mfd_table);    
> >> >
> >> >This device ID is currently handled by the ftdi_sio driver, so I believe
> >> >you at least have to explain how you intend these two drivers to
> >> >cooperate...  
> >> 
> >> these drivers cannot cooperate, the different ftdi function modes
> >> use same device pins as in UART mode. So, you either can use the
> >> device in UART interface mode or in some different mode. I do not
> >> load the ftdi_sio module or do unbind the USB device from the
> >> ftdio_sio driver and bind it to the mfd driver, e.g.:
> >> 
> >>   sh -c "echo -n "3-2:1.0" > /sys/bus/usb/drivers/ftdi_sio/unbind"
> >>   sh -c "echo -n "3-2:1.0" > /sys/bus/usb/drivers/ftdi-mfd/bind"  
> >
> >I'm afraid that's not good enough. If we're going to support a non-UART
> >mode through a separate driver, we need to have all drivers for these
> >devices be able to retrieve the current mode during probe and only bind
> >when the mode matches.
> 
> Can we reliably retrieve the current mode? 

You tell me. ;)

> For devices with connected EEPROM some modes (including UART) are
> configurable in the EEPROM. For devices without EEPROM the default
> mode is always UART, but FIFO-, Bitbang- and MPSSE-mode can be
> switched via commands to the the chip.

IIRC we should be able read from the EEPROM, and I would at least expect
there to be a way to retrieve the current mode as well.

Johan

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

[PATCH 0/3] FPGA Manager support for FPP via FT232H FT245-FIFO Anatolij Gustschin <agust@denx.de> - 2017-07-06 22:50 +0200
  [PATCH 1/3] mfd: Add support for FTDI FT232H devices Anatolij Gustschin <agust@denx.de> - 2017-07-06 22:50 +0200
    Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Bjørn Mork <bjorn@mork.no> - 2017-07-07 09:50 +0200
      Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Anatolij Gustschin <agust@denx.de> - 2017-07-07 12:00 +0200
        Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Johan Hovold <johan@kernel.org> - 2017-07-10 14:40 +0200
          Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Anatolij Gustschin <agust@denx.de> - 2017-07-11 09:00 +0200
            Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Johan Hovold <johan@kernel.org> - 2017-07-12 11:00 +0200
              Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Bjørn Mork <bjorn@mork.no> - 2017-07-12 11:20 +0200
              Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Anatolij Gustschin <agust@denx.de> - 2017-07-13 18:40 +0200
    Re: [PATCH 1/3] mfd: Add support for FTDI FT232H devices Johan Hovold <johan@kernel.org> - 2017-07-10 15:00 +0200
  [PATCH 2/3] gpio: Add FT232H CBUS GPIO driver Anatolij Gustschin <agust@denx.de> - 2017-07-06 22:50 +0200
  [PATCH 3/3] fpga manager: Add FT232H driver for Altera FPP Anatolij Gustschin <agust@denx.de> - 2017-07-06 23:00 +0200
    RE: [PATCH 3/3] fpga manager: Add FT232H driver for Altera FPP David Laight <David.Laight@ACULAB.COM> - 2017-07-07 11:40 +0200

csiph-web