1. 13 2月, 2007 1 次提交
  2. 21 12月, 2006 1 次提交
    • T
      USB: u132-hcd/ftdi-elan: add support for Option GT 3G Quad card · 4b87361d
      Tony Olech 提交于
      ELAN's U132 is a USB to CardBus OHCI controller adapter,
          designed specifically for CardBus 3G data cards to
          function in machines without a CardBus slot.
      The "ftdi-elan" module is a USB client driver, that detects
          a supported CardBus OHCI controller plugged into the
          U132 adapter and thereafter provides the conduit for
          for access by the "u132-hcd" module.
      The "u132-hcd" module is a (cut-down OHCI) host controller
          that supports a single OHCI function of the CardBus 
          card inserted into the U132 adapter.
      
      The problem with the initial implementation is that when
      the CardBus card inserted into the U132 adapter has multiple
      functions (and a CardBus card can support up to 4 functions),
      it was the first function that was arbitrarily choosen.
      
      The first batch of 3G cards tested, like the Merlin Qualcomm
      V620, have two functions each supporting a seperate USB OHCI
      host controller, of which it was that first function that is
      wired up to the 3G modem.
      
      Then along comes the Vodafone Mobile Connect 3G/GPRS data card,
      aka "Option GT 3G Quad" as printed on it's rear or "Option N.V.
      GlobeTrotter Fusion Quad Lite" as read with "lspci -v". And it
      has the meaningful functionality in the second CardBus function.
      
      That presents a problem because it was the "ftdi-elan" module
      alone that knows how to communicate to the embedded CardBus slot
      and the "u132-hcd" module alone that knows how to access the
      pcmcia configuration and CardBus accessible memory space. And
      of course, the information about attached (internally hardwired)
      devices is contained within USB configuration embedded somewhere
      within the CardBus card.
      
      If only the "u132-hcd" module probe() interface could return a
      result code that propagated back to the instigating function
      platform_device_register() then the "ftdi-elan" module could
      try an alternative CardBus function.     However in spite of
      the recent changes to the drivers/base/ routines that moved 
      device_attach() from bus_add_device() to bus_attach_device()
      both of those routines lose the "failed to attach" 0 result
      code and thus the calling routine, namely device_add() is
      incapable of propaging the "failed to attach" condition back
      to platform_device_add() and consequently back to the caller
      of platform_device_register()
      
      Experiments show that patching bus_attach_device() to return
      ENODEV fails with the kernel locking up very early during
      boot. But, however, if the patch is restricted to calls from
      platform_device_add() then it does seem to work.
      
      Unfortunately, until the kernel's drivers/base is properly
      modified to propagate -ENODEV back to the caller of
      platform_device_register(), it is necessary to "fix" the
      "ftdi-elan" module by importing knowledge from the 
      "u132-hcd" module. This is the reason for the duplicated
      functionality introduced in this patch.
      Signed-off-by: NTony Olech <tony.olech@elandigitalsystems.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      4b87361d
  3. 02 12月, 2006 2 次提交
  4. 22 11月, 2006 1 次提交
  5. 18 10月, 2006 2 次提交
  6. 05 10月, 2006 1 次提交
    • D
      IRQ: Maintain regs pointer globally rather than passing to IRQ handlers · 7d12e780
      David Howells 提交于
      Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
      of passing regs around manually through all ~1800 interrupt handlers in the
      Linux kernel.
      
      The regs pointer is used in few places, but it potentially costs both stack
      space and code to pass it around.  On the FRV arch, removing the regs parameter
      from all the genirq function results in a 20% speed up of the IRQ exit path
      (ie: from leaving timer_interrupt() to leaving do_IRQ()).
      
      Where appropriate, an arch may override the generic storage facility and do
      something different with the variable.  On FRV, for instance, the address is
      maintained in GR28 at all times inside the kernel as part of general exception
      handling.
      
      Having looked over the code, it appears that the parameter may be handed down
      through up to twenty or so layers of functions.  Consider a USB character
      device attached to a USB hub, attached to a USB controller that posts its
      interrupts through a cascaded auxiliary interrupt controller.  A character
      device driver may want to pass regs to the sysrq handler through the input
      layer which adds another few layers of parameter passing.
      
      I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
      main part of the code on FRV and i386, though I can't test most of the drivers.
      I've also done partial conversion for powerpc and MIPS - these at least compile
      with minimal configurations.
      
      This will affect all archs.  Mostly the changes should be relatively easy.
      Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
      
      	struct pt_regs *old_regs = set_irq_regs(regs);
      
      And put the old one back at the end:
      
      	set_irq_regs(old_regs);
      
      Don't pass regs through to generic_handle_irq() or __do_IRQ().
      
      In timer_interrupt(), this sort of change will be necessary:
      
      	-	update_process_times(user_mode(regs));
      	-	profile_tick(CPU_PROFILING, regs);
      	+	update_process_times(user_mode(get_irq_regs()));
      	+	profile_tick(CPU_PROFILING);
      
      I'd like to move update_process_times()'s use of get_irq_regs() into itself,
      except that i386, alone of the archs, uses something other than user_mode().
      
      Some notes on the interrupt handling in the drivers:
      
       (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
           the input_dev struct.
      
       (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
           something different depending on whether it's been supplied with a regs
           pointer or not.
      
       (*) Various IRQ handler function pointers have been moved to type
           irq_handler_t.
      Signed-Off-By: NDavid Howells <dhowells@redhat.com>
      (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
      7d12e780
  7. 04 10月, 2006 1 次提交
  8. 28 9月, 2006 1 次提交
    • T
      USB: ftdi-elan: client driver for ELAN Uxxx adapters · a5c66e4b
      Tony Olech 提交于
      This "ftdi-elan" module is one half of the "driver" for
      ELAN's Uxxx series adapters which are USB to PCMCIA CardBus
      adapters. Currently only the U132 adapter is available and
      it's module is called "u132-hcd".
      
      When the USB hot plug subsystem detects a Uxxx series adapter
      it should load this module.
      
      Upon a successful device probe() the jtag device file interface
      is created and the status workqueue started up.
      
      The jtag device file interface exists for the purpose of
      updating the firmware in the Uxxx series adapter, but as
      yet it had never been used.
      
      The status workqueue initializes the Uxxx and then sits there
      polling the Uxxx until a supported PCMCIA CardBus device is
      detected it will start the command and respond workqueues
      and then load the module that handles the device. This will
      initially be only the u132-hcd module. The status workqueue
      then just polls the Uxxx looking for card ejects.
      
      The command and respond workqueues implement a command
      sequencer for communicating with the firmware on the other
      side of the FTDI chip in the Uxxx. This "ftdi-elan" module
      exports some functions to interface with the sequencer.
      
      Note that this module is a USB client driver.
      
      Note that the "u132-hcd" module is a (cut-down OHCI)
      host controller.
      
      Thus we have a topology with the parent of a host controller
      being a USB client! This really stresses the USB subsystem
      semaphore/mutex handling in the module removal.
      Signed-off-by: NTony Olech <tony.olech@elandigitalsystems.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      
      a5c66e4b