diff options
Diffstat (limited to 'arch/sh/boards/bigsur/led.c')
| -rw-r--r-- | arch/sh/boards/bigsur/led.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/arch/sh/boards/bigsur/led.c b/arch/sh/boards/bigsur/led.c new file mode 100644 index 000000000000..0a2339c69440 --- /dev/null +++ b/arch/sh/boards/bigsur/led.c @@ -0,0 +1,55 @@ +/* + * linux/arch/sh/kernel/led_bigsur.c + * + * By Dustin McIntire (dustin@sensoria.com) (c)2001 + * Derived from led_se.c and led.c, which bore the message: + * Copyright (C) 2000 Stuart Menefy <stuart.menefy@st.com> + * + * May be copied or modified under the terms of the GNU General Public + * License. See linux/COPYING for more information. + * + * This file contains Big Sur specific LED code. + */ + +#include <linux/config.h> +#include <asm/io.h> +#include <asm/bigsur/bigsur.h> + +static void mach_led(int position, int value) +{ + int word; + + word = bigsur_inl(BIGSUR_CSLR); + if (value) { + bigsur_outl(word & ~BIGSUR_LED, BIGSUR_CSLR); + } else { + bigsur_outl(word | BIGSUR_LED, BIGSUR_CSLR); + } +} + +#ifdef CONFIG_HEARTBEAT + +#include <linux/sched.h> + +/* Cycle the LED on/off */ +void heartbeat_bigsur(void) +{ + static unsigned cnt = 0, period = 0, dist = 0; + + if (cnt == 0 || cnt == dist) + mach_led( -1, 1); + else if (cnt == 7 || cnt == dist+7) + mach_led( -1, 0); + + if (++cnt > period) { + cnt = 0; + /* The hyperbolic function below modifies the heartbeat period + * length in dependency of the current (5min) load. It goes + * through the points f(0)=126, f(1)=86, f(5)=51, + * f(inf)->30. */ + period = ((672<<FSHIFT)/(5*avenrun[0]+(7<<FSHIFT))) + 30; + dist = period / 4; + } +} +#endif /* CONFIG_HEARTBEAT */ + |