ACPI: Add ec_read and ec_write external functions

  Other ec.c cleanups, too

drivers/acpi/acpi_ksyms.c

@@ -24,6 +24,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/acpi.h>
 #include "include/acpi.h"
 #include "acpi_bus.h"
 
@@ -141,3 +142,11 @@ EXPORT_SYMBOL(acpi_pci_irq_enable);
 extern int acpi_pci_irq_lookup (int segment, int bus, int device, int pin);
 EXPORT_SYMBOL(acpi_pci_irq_lookup);
 #endif /*CONFIG_ACPI_PCI */
+
+#ifdef CONFIG_ACPI_EC
+/* ACPI EC driver (ec.c) */
+
+EXPORT_SYMBOL(ec_read);
+EXPORT_SYMBOL(ec_write);
+#endif
+

drivers/acpi/ec.c

@@ -92,6 +92,9 @@ struct acpi_ec {
 /* If we find an EC via the ECDT, we need to keep a ptr to its context */
 static struct acpi_ec	*ec_ecdt;
 
+/* External interfaces use first EC only, so remember */
+static struct acpi_device *first_ec;
+
 /* --------------------------------------------------------------------------
                              Transaction Management
    -------------------------------------------------------------------------- */
@@ -236,6 +239,47 @@ acpi_ec_write (
 	return_VALUE(result);
 }
 
+/*
+ * Externally callable EC access functions. For now, assume 1 EC only
+ */
+int
+ec_read(u8 addr, u8 *val)
+{
+	struct acpi_ec *ec;
+	int err;
+	u32 temp_data;
+
+	if (!first_ec)
+		return -ENODEV;
+
+	ec = acpi_driver_data(first_ec);
+
+	err = acpi_ec_read(ec, addr, &temp_data);
+
+	if (!err) {
+		*val = temp_data;
+		return 0;
+	}
+	else
+		return err;
+}
+
+int
+ec_write(u8 addr, u8 val)
+{
+	struct acpi_ec *ec;
+	int err;
+
+	if (!first_ec)
+		return -ENODEV;
+
+	ec = acpi_driver_data(first_ec);
+
+	err = acpi_ec_write(ec, addr, val);
+
+	return err;
+}
+
 
 static int
 acpi_ec_query (
@@ -540,11 +584,15 @@ acpi_ec_add (
 	acpi_evaluate_integer(ec->handle, "_GLK", NULL, &ec->global_lock);
 
 	/* If our UID matches the UID for the ECDT-enumerated EC,
-	   we already found this EC, so abort. */
+	   we now have the *real* EC info, so kill the makeshift one.*/
 	acpi_evaluate_integer(ec->handle, "_UID", NULL, &uid);
 	if (ec_ecdt && ec_ecdt->uid == uid) {
-		result = -ENODEV;
-		goto end;
+		acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
+			ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
+	
+		acpi_remove_gpe_handler(ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
+
+		kfree(ec_ecdt);
 	}
 
 	/* Get GPE bit assignment (EC events). */
@@ -564,6 +612,9 @@ acpi_ec_add (
 		acpi_device_name(device), acpi_device_bid(device),
 		(u32) ec->gpe_bit);
 
+	if (!first_ec)
+		first_ec = device;
+
 end:
 	if (result)
 		kfree(ec);
@@ -584,7 +635,7 @@ acpi_ec_remove (
 	if (!device)
 		return_VALUE(-EINVAL);
 
-	ec = (struct acpi_ec *) acpi_driver_data(device);
+	ec = acpi_driver_data(device);
 
 	acpi_ec_remove_fs(device);
 
@@ -609,7 +660,7 @@ acpi_ec_start (
 	if (!device)
 		return_VALUE(-EINVAL);
 
-	ec = (struct acpi_ec *) acpi_driver_data(device);
+	ec = acpi_driver_data(device);
 
 	if (!ec)
 		return_VALUE(-EINVAL);
@@ -688,7 +739,7 @@ acpi_ec_stop (
 	if (!device)
 		return_VALUE(-EINVAL);
 
-	ec = (struct acpi_ec *) acpi_driver_data(device);
+	ec = acpi_driver_data(device);
 
 	status = acpi_remove_address_space_handler(ec->handle,
 		ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
@@ -711,12 +762,13 @@ acpi_ec_ecdt_probe (void)
 
 	status = acpi_get_firmware_table("ECDT", 1, ACPI_LOGICAL_ADDRESSING, 
 		(acpi_table_header **) &ecdt_ptr);
-	if (ACPI_SUCCESS(status)) {
+	if (ACPI_FAILURE(status))
+		return 0;
+
 	printk(KERN_INFO PREFIX "Found ECDT\n");
 
 	 /*
-		 * TODO: When the new driver model allows it, simply tell the
-		 * EC driver it has a new device via that, instead if this.
+	 * Generate a temporary ec context to use until the namespace is scanned
 	 */
 	ec_ecdt = kmalloc(sizeof(struct acpi_ec), GFP_KERNEL);
 	if (!ec_ecdt)
@@ -755,7 +807,6 @@ acpi_ec_ecdt_probe (void)
 			&acpi_ec_gpe_handler);
 		goto error;
 	}
-	}
 
 	return 0;
 
@@ -795,20 +846,6 @@ subsys_initcall(acpi_ec_init);
 
 /* EC driver currently not unloadable */
 #if 0
-static void __exit
-acpi_ec_ecdt_exit (void)
-{
-	if (!ec_ecdt)
-		return;
-
-	acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
-		ACPI_ADR_SPACE_EC, &acpi_ec_space_handler);
-	
-	acpi_remove_gpe_handler(ec_ecdt->gpe_bit, &acpi_ec_gpe_handler);
-
-	kfree(ec_ecdt);
-}
-
 static void __exit
 acpi_ec_exit (void)
 {
@@ -818,8 +855,6 @@ acpi_ec_exit (void)
 
 	remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
 
-	acpi_ec_ecdt_exit();
-
 	return_VOID;
 }
 #endif /* 0 */

include/linux/acpi.h

@@ -419,6 +419,12 @@ int acpi_pci_irq_init (void);
 
 #endif /*CONFIG_ACPI_PCI*/
 
+#ifdef CONFIG_ACPI_EC
+
+int ec_read(u8 addr, u8 *val);
+int ec_write(u8 addr, u8 val);
+
+#endif /*CONFIG_ACPI_EC*/
 
 #ifdef CONFIG_ACPI