5 files changed, 217 insertions, 93 deletions

diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index 746411518802..08e0140920e1 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -104,6 +104,24 @@ config ACPI_SYSFS_POWER
         help
           Say N to disable power /sys interface
 
+config ACPI_EC_DEBUGFS
+        tristate "EC read/write access through /sys/kernel/debug/ec"
+        default n
+        help
+          Say N to disable Embedded Controller /sys/kernel/debug interface
+
+          Be aware that using this interface can confuse your Embedded
+          Controller in a way that a normal reboot is not enough. You then
+          have to power of your system, and remove the laptop battery for
+          some seconds.
+          An Embedded Controller typically is available on laptops and reads
+          sensor values like battery state and temperature.
+          The kernel accesses the EC through ACPI parsed code provided by BIOS
+          tables. This option allows to access the EC directly without ACPI
+          code being involved.
+          Thus this option is a debug option that helps to write ACPI drivers
+          and can be used to identify ACPI code or EC firmware bugs.
+
 config ACPI_PROC_EVENT
         bool "Deprecated /proc/acpi/event support"
         depends on PROC_FS
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 6ee33169e1dc..833b582d1762 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -60,6 +60,7 @@ obj-$(CONFIG_ACPI_SBS)		+= sbshc.o
 obj-$(CONFIG_ACPI_SBS)          += sbs.o
 obj-$(CONFIG_ACPI_POWER_METER)  += power_meter.o
 obj-$(CONFIG_ACPI_HED)          += hed.o
+obj-$(CONFIG_ACPI_EC_DEBUGFS)   += ec_sys.o
 
 # processor has its own "processor." module_param namespace
 processor-y                     := processor_driver.o processor_throttling.o
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 5f2027d782e8..1fa0aafebe2a 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -34,8 +34,6 @@
 #include <linux/init.h>
 #include <linux/types.h>
 #include <linux/delay.h>
-#include <linux/proc_fs.h>
-#include <linux/seq_file.h>
 #include <linux/interrupt.h>
 #include <linux/list.h>
 #include <linux/spinlock.h>
@@ -45,10 +43,13 @@
 #include <acpi/acpi_drivers.h>
 #include <linux/dmi.h>
 
+#include "internal.h"
+
 #define ACPI_EC_CLASS                   "embedded_controller"
 #define ACPI_EC_DEVICE_NAME             "Embedded Controller"
 #define ACPI_EC_FILE_INFO               "info"
 
+#undef PREFIX
 #define PREFIX                          "ACPI: EC: "
 
 /* EC status register */
@@ -106,19 +107,8 @@ struct transaction {
         bool done;
 };
 
-static struct acpi_ec {
-        acpi_handle handle;
-        unsigned long gpe;
-        unsigned long command_addr;
-        unsigned long data_addr;
-        unsigned long global_lock;
-        unsigned long flags;
-        struct mutex lock;
-        wait_queue_head_t wait;
-        struct list_head list;
-        struct transaction *curr;
-        spinlock_t curr_lock;
-} *boot_ec, *first_ec;
+struct acpi_ec *boot_ec, *first_ec;
+EXPORT_SYMBOL(first_ec);
 
 static int EC_FLAGS_MSI; /* Out-of-spec MSI controller */
 static int EC_FLAGS_VALIDATE_ECDT; /* ASUStec ECDTs need to be validated */
@@ -679,72 +669,6 @@ acpi_ec_space_handler(u32 function, acpi_physical_address address,
 }
 
 /* --------------------------------------------------------------------------
-                              FS Interface (/proc)
-   -------------------------------------------------------------------------- */
-
-static struct proc_dir_entry *acpi_ec_dir;
-
-static int acpi_ec_read_info(struct seq_file *seq, void *offset)
-{
-        struct acpi_ec *ec = seq->private;
-
-        if (!ec)
-                goto end;
-
-        seq_printf(seq, "gpe:\t\t\t0x%02x\n", (u32) ec->gpe);
-        seq_printf(seq, "ports:\t\t\t0x%02x, 0x%02x\n",
-                   (unsigned)ec->command_addr, (unsigned)ec->data_addr);
-        seq_printf(seq, "use global lock:\t%s\n",
-                   ec->global_lock ? "yes" : "no");
-      end:
-        return 0;
-}
-
-static int acpi_ec_info_open_fs(struct inode *inode, struct file *file)
-{
-        return single_open(file, acpi_ec_read_info, PDE(inode)->data);
-}
-
-static const struct file_operations acpi_ec_info_ops = {
-        .open = acpi_ec_info_open_fs,
-        .read = seq_read,
-        .llseek = seq_lseek,
-        .release = single_release,
-        .owner = THIS_MODULE,
-};
-
-static int acpi_ec_add_fs(struct acpi_device *device)
-{
-        struct proc_dir_entry *entry = NULL;
-
-        if (!acpi_device_dir(device)) {
-                acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
-                                                     acpi_ec_dir);
-                if (!acpi_device_dir(device))
-                        return -ENODEV;
-        }
-
-        entry = proc_create_data(ACPI_EC_FILE_INFO, S_IRUGO,
-                                 acpi_device_dir(device),
-                                 &acpi_ec_info_ops, acpi_driver_data(device));
-        if (!entry)
-                return -ENODEV;
-        return 0;
-}
-
-static int acpi_ec_remove_fs(struct acpi_device *device)
-{
-
-        if (acpi_device_dir(device)) {
-                remove_proc_entry(ACPI_EC_FILE_INFO, acpi_device_dir(device));
-                remove_proc_entry(acpi_device_bid(device), acpi_ec_dir);
-                acpi_device_dir(device) = NULL;
-        }
-
-        return 0;
-}
-
-/* --------------------------------------------------------------------------
                                Driver Interface
    -------------------------------------------------------------------------- */
 static acpi_status
@@ -894,7 +818,12 @@ static int acpi_ec_add(struct acpi_device *device)
         if (!first_ec)
                 first_ec = ec;
         device->driver_data = ec;
-        acpi_ec_add_fs(device);
+
+        WARN(!request_region(ec->data_addr, 1, "EC data"),
+             "Could not request EC data io port 0x%lx", ec->data_addr);
+        WARN(!request_region(ec->command_addr, 1, "EC cmd"),
+             "Could not request EC cmd io port 0x%lx", ec->command_addr);
+
         pr_info(PREFIX "GPE = 0x%lx, I/O: command/status = 0x%lx, data = 0x%lx\n",
                           ec->gpe, ec->command_addr, ec->data_addr);
 
@@ -921,7 +850,8 @@ static int acpi_ec_remove(struct acpi_device *device, int type)
                 kfree(handler);
         }
         mutex_unlock(&ec->lock);
-        acpi_ec_remove_fs(device);
+        release_region(ec->data_addr, 1);
+        release_region(ec->command_addr, 1);
         device->driver_data = NULL;
         if (ec == first_ec)
                 first_ec = NULL;
@@ -1120,16 +1050,10 @@ int __init acpi_ec_init(void)
 {
         int result = 0;
 
-        acpi_ec_dir = proc_mkdir(ACPI_EC_CLASS, acpi_root_dir);
-        if (!acpi_ec_dir)
-                return -ENODEV;
-
         /* Now register the driver for the EC */
         result = acpi_bus_register_driver(&acpi_ec_driver);
-        if (result < 0) {
-                remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
+        if (result < 0)
                 return -ENODEV;
-        }
 
         return result;
 }
@@ -1140,9 +1064,6 @@ static void __exit acpi_ec_exit(void)
 {
 
         acpi_bus_unregister_driver(&acpi_ec_driver);
-
-        remove_proc_entry(ACPI_EC_CLASS, acpi_root_dir);
-
         return;
 }
 #endif  /* 0 */
diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c
new file mode 100644
index 000000000000..0e869b3f81ca
--- /dev/null
+++ b/drivers/acpi/ec_sys.c
@@ -0,0 +1,160 @@
+/*
+ * ec_sys.c
+ *
+ * Copyright (C) 2010 SUSE Products GmbH/Novell
+ * Author:
+ *      Thomas Renninger <trenn@suse.de>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/acpi.h>
+#include <linux/debugfs.h>
+#include "internal.h"
+
+MODULE_AUTHOR("Thomas Renninger <trenn@suse.de>");
+MODULE_DESCRIPTION("ACPI EC sysfs access driver");
+MODULE_LICENSE("GPL");
+
+static bool write_support;
+module_param(write_support, bool, 0644);
+MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
+                 "be needed.");
+
+#define EC_SPACE_SIZE 256
+
+struct sysdev_class acpi_ec_sysdev_class = {
+        .name = "ec",
+};
+
+static struct dentry *acpi_ec_debugfs_dir;
+
+static int acpi_ec_open_io(struct inode *i, struct file *f)
+{
+        f->private_data = i->i_private;
+        return 0;
+}
+
+static ssize_t acpi_ec_read_io(struct file *f, char __user *buf,
+                               size_t count, loff_t *off)
+{
+        /* Use this if support reading/writing multiple ECs exists in ec.c:
+         * struct acpi_ec *ec = ((struct seq_file *)f->private_data)->private;
+         */
+        unsigned int size = EC_SPACE_SIZE;
+        u8 *data = (u8 *) buf;
+        loff_t init_off = *off;
+        int err = 0;
+
+        if (*off >= size)
+                return 0;
+        if (*off + count >= size) {
+                size -= *off;
+                count = size;
+        } else
+                size = count;
+
+        while (size) {
+                err = ec_read(*off, &data[*off - init_off]);
+                if (err)
+                        return err;
+                *off += 1;
+                size--;
+        }
+        return count;
+}
+
+static ssize_t acpi_ec_write_io(struct file *f, const char __user *buf,
+                                size_t count, loff_t *off)
+{
+        /* Use this if support reading/writing multiple ECs exists in ec.c:
+         * struct acpi_ec *ec = ((struct seq_file *)f->private_data)->private;
+         */
+
+        unsigned int size = count;
+        loff_t init_off = *off;
+        u8 *data = (u8 *) buf;
+        int err = 0;
+
+        if (*off >= EC_SPACE_SIZE)
+                return 0;
+        if (*off + count >= EC_SPACE_SIZE) {
+                size = EC_SPACE_SIZE - *off;
+                count = size;
+        }
+
+        while (size) {
+                u8 byte_write = data[*off - init_off];
+                err = ec_write(*off, byte_write);
+                if (err)
+                        return err;
+
+                *off += 1;
+                size--;
+        }
+        return count;
+}
+
+static struct file_operations acpi_ec_io_ops = {
+        .owner = THIS_MODULE,
+        .open  = acpi_ec_open_io,
+        .read  = acpi_ec_read_io,
+        .write = acpi_ec_write_io,
+};
+
+int acpi_ec_add_debugfs(struct acpi_ec *ec, unsigned int ec_device_count)
+{
+        struct dentry *dev_dir;
+        char name[64];
+        mode_t mode = 0400;
+
+        if (ec_device_count == 0) {
+                acpi_ec_debugfs_dir = debugfs_create_dir("ec", NULL);
+                if (!acpi_ec_debugfs_dir)
+                        return -ENOMEM;
+        }
+
+        sprintf(name, "ec%u", ec_device_count);
+        dev_dir = debugfs_create_dir(name, acpi_ec_debugfs_dir);
+        if (!dev_dir) {
+                if (ec_device_count != 0)
+                        goto error;
+                return -ENOMEM;
+        }
+
+        if (!debugfs_create_x32("gpe", 0444, dev_dir, (u32 *)&first_ec->gpe))
+                goto error;
+        if (!debugfs_create_bool("use_global_lock", 0444, dev_dir,
+                                 (u32 *)&first_ec->global_lock))
+                goto error;
+
+        if (write_support)
+                mode = 0600;
+        if (!debugfs_create_file("io", mode, dev_dir, ec, &acpi_ec_io_ops))
+                goto error;
+
+        return 0;
+
+error:
+        debugfs_remove_recursive(acpi_ec_debugfs_dir);
+        return -ENOMEM;
+}
+
+static int __init acpi_ec_sys_init(void)
+{
+        int err = 0;
+        if (first_ec)
+                err = acpi_ec_add_debugfs(first_ec, 0);
+        else
+                err = -ENODEV;
+        return err;
+}
+
+static void __exit acpi_ec_sys_exit(void)
+{
+        debugfs_remove_recursive(acpi_ec_debugfs_dir);
+}
+
+module_init(acpi_ec_sys_init);
+module_exit(acpi_ec_sys_exit);
diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h
index f8f190ec066e..8ae27264a00e 100644
--- a/drivers/acpi/internal.h
+++ b/drivers/acpi/internal.h
@@ -18,6 +18,11 @@
  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+#ifndef _ACPI_INTERNAL_H_
+#define _ACPI_INTERNAL_H_
+
+#include <linux/sysdev.h>
+
 #define PREFIX "ACPI: "
 
 int init_acpi_device_notify(void);
@@ -46,6 +51,23 @@ void acpi_early_processor_set_pdc(void);
 /* --------------------------------------------------------------------------
                                   Embedded Controller
    -------------------------------------------------------------------------- */
+struct acpi_ec {
+        acpi_handle handle;
+        unsigned long gpe;
+        unsigned long command_addr;
+        unsigned long data_addr;
+        unsigned long global_lock;
+        unsigned long flags;
+        struct mutex lock;
+        wait_queue_head_t wait;
+        struct list_head list;
+        struct transaction *curr;
+        spinlock_t curr_lock;
+        struct sys_device sysdev;
+};
+
+extern struct acpi_ec *first_ec;
+
 int acpi_ec_init(void);
 int acpi_ec_ecdt_probe(void);
 int acpi_boot_ec_enable(void);
@@ -63,3 +85,5 @@ int acpi_sleep_proc_init(void);
 #else
 static inline int acpi_sleep_proc_init(void) { return 0; }
 #endif
+
+#endif /* _ACPI_INTERNAL_H_ */