USB: ftdi-elan: client driver for ELAN Uxxx adapters

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: Tony Olech <tony.olech@elandigitalsystems.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 24 insertions, 0 deletions

diff --git a/drivers/usb/misc/Kconfig b/drivers/usb/misc/Kconfig
index 288d301d2bf..c29658f69e2 100644
--- a/drivers/usb/misc/Kconfig
+++ b/drivers/usb/misc/Kconfig
@@ -178,6 +178,30 @@ config USB_IDMOUSE
 
           See also <http://www.fs.tum.de/~echtler/idmouse/>.
 
+config USB_FTDI_ELAN
+        tristate "Elan PCMCIA CardBus Adapter USB Client"
+        depends on USB
+        default M
+        help
+          ELAN's Uxxx series of adapters are USB to PCMCIA CardBus adapters.
+          Currently only the U132 adapter is available.
+
+          The U132 is specifically designed for CardBus PC cards that contain
+          an OHCI host controller. Typical PC cards are the Orange Mobile 3G
+          Option GlobeTrotter Fusion card. The U132 adapter will *NOT* work
+          with PC cards that do not contain an OHCI controller. To use a U132
+          adapter you will need this "ftdi-elan" module as well as the "u132-hcd"
+          module which is a USB host controller driver that talks to the OHCI
+          controller within CardBus card that are inserted in the U132 adapter.
+
+          This driver has been tested with a CardBus OHCI USB adapter, and
+          worked with a USB PEN Drive inserted into the first USB port of
+          the PCCARD. A rather pointless thing to do, but useful for testing.
+
+          See also the USB_U132_HCD entry "Elan U132 Adapter Host Controller"
+
+          It is safe to say M here.
+
 config USB_APPLEDISPLAY
         tristate "Apple Cinema Display support"
         depends on USB