watchdog: ts4800: add driver for TS-4800 watchdog

This watchdog is instantiated in a FPGA that is memory mapped. It is
made of only one register, called the feed register. Writing to this
register will re-arm the watchdog for a given time (and enable it if it
was disable). It can be disabled by writing a special value into it.

It is part of a syscon block, and the watchdog register offset in this
block varies from board to board. This offset is passed in the syscon
property after the phandle to the syscon node.

Signed-off-by: Damien Riegel <damien.riegel@savoirfairelinux.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 2116e088fd25..62ac67f8bcab 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -433,6 +433,16 @@ config NUC900_WATCHDOG
           To compile this driver as a module, choose M here: the
           module will be called nuc900_wdt.
 
+config TS4800_WATCHDOG
+        tristate "TS-4800 Watchdog"
+        depends on HAS_IOMEM && OF
+        select WATCHDOG_CORE
+        select MFD_SYSCON
+        help
+          Technologic Systems TS-4800 has watchdog timer implemented in
+          an external FPGA. Say Y here if you want to support for the
+          watchdog timer on TS-4800 board.
+
 config TS72XX_WATCHDOG
         tristate "TS-72XX SBC Watchdog"
         depends on MACH_TS72XX