x86, olpc: EC SCI wakeup mask functionality

Update the EC SCI masks with recent additions.

Add functions to query SCI events and set the wakeup mask, to be used by
followup patches.

Add functions to tweak an event mask used to select certain EC events as
a system wakeup source. Also add a function to determine if EC wakeup
functionality is available, as this depends on child drivers (different
for each laptop model) to configure the SCI interrupt.

Signed-off-by: Daniel Drake <dsd@laptop.org>
Link: http://lkml.kernel.org/r/1309019658-1712-7-git-send-email-dsd@laptop.org
Acked-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 86 insertions, 0 deletions

diff --git a/arch/x86/platform/olpc/olpc.c b/arch/x86/platform/olpc/olpc.c
index 0060fd59ea0..72fd041762f 100644
--- a/arch/x86/platform/olpc/olpc.c
+++ b/arch/x86/platform/olpc/olpc.c
@@ -19,6 +19,7 @@
 #include <linux/string.h>
 #include <linux/platform_device.h>
 #include <linux/of.h>
+#include <linux/syscore_ops.h>
 
 #include <asm/geode.h>
 #include <asm/setup.h>
@@ -30,6 +31,9 @@ EXPORT_SYMBOL_GPL(olpc_platform_info);
 
 static DEFINE_SPINLOCK(ec_lock);
 
+/* EC event mask to be applied during suspend (defining wakeup sources). */
+static u16 ec_wakeup_mask;
+
 /* what the timeout *should* be (in ms) */
 #define EC_BASE_TIMEOUT 20
 
@@ -188,6 +192,79 @@ err:
 }
 EXPORT_SYMBOL_GPL(olpc_ec_cmd);
 
+void olpc_ec_wakeup_set(u16 value)
+{
+	ec_wakeup_mask |= value;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_wakeup_set);
+
+void olpc_ec_wakeup_clear(u16 value)
+{
+	ec_wakeup_mask &= ~value;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_wakeup_clear);
+
+/*
+ * Returns true if the compile and runtime configurations allow for EC events
+ * to wake the system.
+ */
+bool olpc_ec_wakeup_available(void)
+{
+	if (!machine_is_olpc())
+		return false;
+
+	/*
+	 * XO-1 EC wakeups are available when olpc-xo1-sci driver is
+	 * compiled in
+	 */
+#ifdef CONFIG_OLPC_XO1_SCI
+	if (olpc_platform_info.boardrev < olpc_board_pre(0xd0)) /* XO-1 */
+		return true;
+#endif
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_wakeup_available);
+
+int olpc_ec_mask_write(u16 bits)
+{
+	if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
+		__be16 ec_word = cpu_to_be16(bits);
+		return olpc_ec_cmd(EC_WRITE_EXT_SCI_MASK, (void *) &ec_word, 2,
+				   NULL, 0);
+	} else {
+		unsigned char ec_byte = bits & 0xff;
+		return olpc_ec_cmd(EC_WRITE_SCI_MASK, &ec_byte, 1, NULL, 0);
+	}
+}
+EXPORT_SYMBOL_GPL(olpc_ec_mask_write);
+
+int olpc_ec_sci_query(u16 *sci_value)
+{
+	int ret;
+
+	if (olpc_platform_info.flags & OLPC_F_EC_WIDE_SCI) {
+		__be16 ec_word;
+		ret = olpc_ec_cmd(EC_EXT_SCI_QUERY,
+			NULL, 0, (void *) &ec_word, 2);
+		if (ret == 0)
+			*sci_value = be16_to_cpu(ec_word);
+	} else {
+		unsigned char ec_byte;
+		ret = olpc_ec_cmd(EC_SCI_QUERY, NULL, 0, &ec_byte, 1);
+		if (ret == 0)
+			*sci_value = ec_byte;
+	}
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(olpc_ec_sci_query);
+
+static int olpc_ec_suspend(void)
+{
+	return olpc_ec_mask_write(ec_wakeup_mask);
+}
+
 static bool __init check_ofw_architecture(struct device_node *root)
 {
 	const char *olpc_arch;
@@ -242,6 +319,10 @@ static int __init add_xo1_platform_devices(void)
 	return 0;
 }
 
+static struct syscore_ops olpc_syscore_ops = {
+	.suspend = olpc_ec_suspend,
+};
+
 static int __init olpc_init(void)
 {
 	int r = 0;
@@ -266,6 +347,9 @@ static int __init olpc_init(void)
 			!cs5535_has_vsa2())
 		x86_init.pci.arch_init = pci_olpc_init;
 #endif
+	/* EC version 0x5f adds support for wide SCI mask */
+	if (olpc_platform_info.ecver >= 0x5f)
+		olpc_platform_info.flags |= OLPC_F_EC_WIDE_SCI;
 
 	printk(KERN_INFO "OLPC board revision %s%X (EC=%x)\n",
 			((olpc_platform_info.boardrev & 0xf) < 8) ? "pre" : "",
@@ -278,6 +362,8 @@ static int __init olpc_init(void)
 			return r;
 	}
 
+	register_syscore_ops(&olpc_syscore_ops);
+
 	return 0;
 }