From 4cf9e464f78e58117b9a57e1e4e092e609d96b59 Mon Sep 17 00:00:00 2001 From: Stefan Roese Date: Tue, 19 Jul 2016 07:45:46 +0200 Subject: misc: Add simple driver for some Nuvoton NCT6102D devices This simple driver provides some functions to control some of the integrated devices. The watchdog is enabled per default. This driver adds a function to disable the watchdog. Also the internal legacy UART (io address 0x3f8/0x2f8) is enabled per default. Signed-off-by: Stefan Roese Reviewed-by: Bin Meng Cc: Simon Glass --- drivers/misc/nuvoton_nct6102d.c | 56 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 56 insertions(+) create mode 100644 drivers/misc/nuvoton_nct6102d.c (limited to 'drivers/misc/nuvoton_nct6102d.c') diff --git a/drivers/misc/nuvoton_nct6102d.c b/drivers/misc/nuvoton_nct6102d.c new file mode 100644 index 0000000..ced70f1 --- /dev/null +++ b/drivers/misc/nuvoton_nct6102d.c @@ -0,0 +1,56 @@ +/* + * Copyright (C) 2016 Stefan Roese + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include +#include + +static void superio_outb(int reg, int val) +{ + outb(reg, NCT_EFER); + outb(val, NCT_EFDR); +} + +static inline int superio_inb(int reg) +{ + outb(reg, NCT_EFER); + return inb(NCT_EFDR); +} + +static int superio_enter(void) +{ + outb(NCT_ENTRY_KEY, NCT_EFER); /* Enter extended function mode */ + outb(NCT_ENTRY_KEY, NCT_EFER); /* Again according to manual */ + + return 0; +} + +static void superio_select(int ld) +{ + superio_outb(NCT_LD_SELECT_REG, ld); +} + +static void superio_exit(void) +{ + outb(NCT_EXIT_KEY, NCT_EFER); /* Leave extended function mode */ +} + +/* + * The Nuvoton NCT6102D starts per default after reset with both, + * the internal watchdog and the internal legacy UART enabled. This + * code provides a function to disable the watchdog. + */ +int nct6102d_wdt_disable(void) +{ + superio_enter(); + /* Select logical device for WDT */ + superio_select(NCT6102D_LD_WDT); + superio_outb(NCT6102D_WDT_TIMEOUT, 0x00); + superio_exit(); + + return 0; +} -- cgit v1.1