[PARISC] PDC_CHASSIS is implemented on all machines

This patch removes a limitation of the original code, so that CHASSIS
codes can be sent to all machines. On machines with a LCD panel, this
code displays "INI" during bootup, "RUN" when the system is booted and
running, "FLT" when a panic occurs, etc.

This part of the code can be enabled/disabled through CONFIG_PDC_CHASSIS

This patch also adds minimalistic support for Chassis warnings, through
a proc entry '/proc/chassis', which will reflect the warnings status (PSU
or fans failure when they happen, NVRAM battery level and temperature
thresholds overflows).

This part of the code can be enabled/disabled through CONFIG_PDC_CHASSIS_WARN

Signed-off-by: Thibaut VARENE <varenet@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c
index 2dc06b8..0596f27 100644
--- a/arch/parisc/kernel/firmware.c
+++ b/arch/parisc/kernel/firmware.c
@@ -11,7 +11,7 @@
  * Copyright 1999 The Puffin Group, (Alex deVries, David Kennedy)
  * Copyright 2003 Grant Grundler <grundler parisc-linux org>
  * Copyright 2003,2004 Ryan Bradetich <rbrad@parisc-linux.org>
- * Copyright 2004 Thibaut VARENE <varenet@parisc-linux.org>
+ * Copyright 2004,2006 Thibaut VARENE <varenet@parisc-linux.org>
  *
  *    This program is free software; you can redistribute it and/or modify
  *    it under the terms of the GNU General Public License as published by
@@ -252,10 +252,8 @@
 #endif
 
 /**
- * pdc_chassis_disp - Updates display
+ * pdc_chassis_disp - Updates chassis code
  * @retval: -1 on error, 0 on success
- *
- * Works on old PDC only (E class, others?)
  */
 int pdc_chassis_disp(unsigned long disp)
 {
@@ -269,6 +267,22 @@
 }
 
 /**
+ * pdc_chassis_warn - Fetches chassis warnings
+ * @retval: -1 on error, 0 on success
+ */
+int pdc_chassis_warn(unsigned long *warn)
+{
+	int retval = 0;
+
+	spin_lock_irq(&pdc_lock);
+	retval = mem_pdc_call(PDC_CHASSIS, PDC_CHASSIS_WARN, __pa(pdc_result));
+	*warn = pdc_result[0];
+	spin_unlock_irq(&pdc_lock);
+
+	return retval;
+}
+
+/**
  * pdc_coproc_cfg - To identify coprocessors attached to the processor.
  * @pdc_coproc_info: Return buffer address.
  *