ACPI: thinkpad-acpi: clean up probing and move init to subdrivers

Move most of the probing code to its own function, and most of the
subdriver-specific init code into subdriver init functions.

This allows us to not define pci_handle unless the dock subdriver is
enabled, as well.

This patch causes a minor userland interface change: if a subdriver doesn't
detect a capability, /proc entries for it are not created anymore (as
opposed to a /proc entry that just returned "unsupported").

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 151 insertions, 84 deletions

diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index 7fa906fd45c0..eeab39418c71 100644
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -277,9 +277,9 @@ static int _sta(acpi_handle handle)
  * ACPI device model
  */
 
-static void __init ibm_handle_init(char *name,
-                                   acpi_handle * handle, acpi_handle parent,
-                                   char **paths, int num_paths, char **path)
+static void ibm_handle_init(char *name,
+                           acpi_handle *handle, acpi_handle parent,
+                           char **paths, int num_paths, char **path)
 {
         int i;
         acpi_status status;
@@ -351,8 +351,8 @@ static int __init register_tpacpi_subdriver(struct ibm_struct *ibm)
 
         ibm->driver = kzalloc(sizeof(struct acpi_driver), GFP_KERNEL);
         if (!ibm->driver) {
-                printk(IBM_ERR "kmalloc(ibm->driver) failed\n");
-                return -1;
+                printk(IBM_ERR "kzalloc(ibm->driver) failed\n");
+                return -ENOMEM;
         }
 
         sprintf(ibm->driver->name, "%s_%s", IBM_NAME, ibm->name);
@@ -364,7 +364,9 @@ static int __init register_tpacpi_subdriver(struct ibm_struct *ibm)
                 printk(IBM_ERR "acpi_bus_register_driver(%s) failed: %d\n",
                        ibm->hid, ret);
                 kfree(ibm->driver);
-        }
+                ibm->driver = NULL;
+        } else if (!ret)
+                ibm->driver_registered = 1;
 
         return ret;
 }
@@ -495,6 +497,8 @@ static int hotkey_orig_mask;
 
 static int hotkey_init(void)
 {
+        IBM_HANDLE_INIT(hkey);
+
         /* hotkey not supported on 570 */
         hotkey_supported = hkey_handle != NULL;
 
@@ -508,13 +512,14 @@ static int hotkey_init(void)
                         return -ENODEV;
         }
 
-        return 0;
+        return (hotkey_supported)? 0 : 1;
 }
 
 static void hotkey_exit(void)
 {
-        if (hotkey_supported)
+        if (hotkey_supported) {
                 hotkey_set(hotkey_orig_status, hotkey_orig_mask);
+        }
 }
 
 static void hotkey_notify(struct ibm_struct *ibm, u32 event)
@@ -628,12 +633,14 @@ static int bluetooth_supported;
 
 static int bluetooth_init(void)
 {
+        IBM_HANDLE_INIT(hkey);
+
         /* bluetooth not supported on 570, 600e/x, 770e, 770x, A21e, A2xm/p,
            G4x, R30, R31, R40e, R50e, T20-22, X20-21 */
         bluetooth_supported = hkey_handle &&
             acpi_evalf(hkey_handle, NULL, "GBDC", "qv");
 
-        return 0;
+        return (bluetooth_supported)? 0 : 1;
 }
 
 static int bluetooth_status(void)
@@ -697,10 +704,12 @@ static int wan_supported;
 
 static int wan_init(void)
 {
+        IBM_HANDLE_INIT(hkey);
+
         wan_supported = hkey_handle &&
             acpi_evalf(hkey_handle, NULL, "GWAN", "qv");
 
-        return 0;
+        return (wan_supported)? 0 : 1;
 }
 
 static int wan_status(void)
@@ -775,6 +784,9 @@ static int video_init(void)
 {
         int ivga;
 
+        IBM_HANDLE_INIT(vid);
+        IBM_HANDLE_INIT(vid2);
+
         if (vid2_handle && acpi_evalf(NULL, &ivga, "\\IVGA", "d") && ivga)
                 /* G41, assume IVGA doesn't change */
                 vid_handle = vid2_handle;
@@ -792,7 +804,7 @@ static int video_init(void)
                 /* all others */
                 video_supported = TPACPI_VIDEO_NEW;
 
-        return 0;
+        return (video_supported != TPACPI_VIDEO_NONE)? 0 : 1;
 }
 
 static void video_exit(void)
@@ -979,6 +991,10 @@ IBM_HANDLE(ledb, ec, "LEDB");		/* G4x */
 
 static int light_init(void)
 {
+        IBM_HANDLE_INIT(ledb);
+        IBM_HANDLE_INIT(lght);
+        IBM_HANDLE_INIT(cmos);
+
         /* light not supported on 570, 600e/x, 770e, 770x, G4x, R30, R31 */
         light_supported = (cmos_handle || lght_handle) && !ledb_handle;
 
@@ -988,7 +1004,7 @@ static int light_init(void)
                 light_status_supported = acpi_evalf(ec_handle, NULL,
                                                     "KBLT", "qv");
 
-        return 0;
+        return (light_supported)? 0 : 1;
 }
 
 static int light_read(char *p)
@@ -1044,9 +1060,6 @@ static int light_write(char *buf)
  * Dock subdriver
  */
 
-/* don't list other alternatives as we install a notify handler on the 570 */
-IBM_HANDLE(pci, root, "\\_SB.PCI");     /* 570 */
-
 #ifdef CONFIG_THINKPAD_ACPI_DOCK
 
 IBM_HANDLE(dock, root, "\\_SB.GDCK",    /* X30, X31, X40 */
@@ -1055,8 +1068,19 @@ IBM_HANDLE(dock, root, "\\_SB.GDCK",	/* X30, X31, X40 */
            "\\_SB.PCI.ISA.SLCE",        /* 570 */
     );                          /* A21e,G4x,R30,R31,R32,R40,R40e,R50e */
 
+/* don't list other alternatives as we install a notify handler on the 570 */
+IBM_HANDLE(pci, root, "\\_SB.PCI");     /* 570 */
+
 #define dock_docked() (_sta(dock_handle) & 1)
 
+static int dock_init(void)
+{
+        IBM_HANDLE_INIT(dock);
+        IBM_HANDLE_INIT(pci);
+
+        return (dock_handle)? 0 : 1;
+}
+
 static void dock_notify(struct ibm_struct *ibm, u32 event)
 {
         int docked = dock_docked();
@@ -1147,6 +1171,13 @@ IBM_HANDLE(bay2_ej, bay2, "_EJ3",	/* 600e/x, 770e, A3x */
 
 static int bay_init(void)
 {
+        IBM_HANDLE_INIT(bay);
+        if (bay_handle)
+                IBM_HANDLE_INIT(bay_ej);
+        IBM_HANDLE_INIT(bay2);
+        if (bay2_handle)
+                IBM_HANDLE_INIT(bay2_ej);
+
         bay_status_supported = bay_handle &&
             acpi_evalf(bay_handle, NULL, "_STA", "qv");
         bay_status2_supported = bay2_handle &&
@@ -1157,7 +1188,8 @@ static int bay_init(void)
         bay_eject2_supported = bay2_handle && bay2_ej_handle &&
             (strlencmp(bay2_ej_path, "_EJ0") == 0 || experimental);
 
-        return 0;
+        return (bay_status_supported || bay_eject_supported ||
+                bay_status2_supported || bay_eject2_supported)? 0 : 1;
 }
 
 static void bay_notify(struct ibm_struct *ibm, u32 event)
@@ -1221,6 +1253,13 @@ static int bay_write(char *buf)
  * CMOS subdriver
  */
 
+static int cmos_init(void)
+{
+        IBM_HANDLE_INIT(cmos);
+
+        return (cmos_handle)? 0 : 1;
+}
+
 static int cmos_eval(int cmos_cmd)
 {
         if (cmos_handle)
@@ -1281,6 +1320,8 @@ IBM_HANDLE(led, ec, "SLED",	/* 570 */
 
 static int led_init(void)
 {
+        IBM_HANDLE_INIT(led);
+
         if (!led_handle)
                 /* led not supported on R30, R31 */
                 led_supported = TPACPI_LED_NONE;
@@ -1294,7 +1335,7 @@ static int led_init(void)
                 /* all others */
                 led_supported = TPACPI_LED_NEW;
 
-        return 0;
+        return (led_supported != TPACPI_LED_NONE)? 0 : 1;
 }
 
 #define led_status(s) ((s) == 0 ? "off" : ((s) == 1 ? "on" : "blinking"))
@@ -1391,6 +1432,13 @@ static int led_write(char *buf)
 
 IBM_HANDLE(beep, ec, "BEEP");   /* all except R30, R31 */
 
+static int beep_init(void)
+{
+        IBM_HANDLE_INIT(beep);
+
+        return (beep_handle)? 0 : 1;
+}
+
 static int beep_read(char *p)
 {
         int len = 0;
@@ -1436,7 +1484,9 @@ static int thermal_init(void)
 {
         u8 t, ta1, ta2;
         int i;
-        int acpi_tmp7 = acpi_evalf(ec_handle, NULL, "TMP7", "qv");
+        int acpi_tmp7;
+
+        acpi_tmp7 = acpi_evalf(ec_handle, NULL, "TMP7", "qv");
 
         if (ibm_thinkpad_ec_found && experimental) {
                 /*
@@ -1492,7 +1542,7 @@ static int thermal_init(void)
                 thermal_read_mode = TPACPI_THERMAL_NONE;
         }
 
-        return 0;
+        return (thermal_read_mode != TPACPI_THERMAL_NONE)? 0 : 1;
 }
 
 static int thermal_get_sensors(struct ibm_thermal_sensors_struct *s)
@@ -1973,6 +2023,10 @@ static int fan_init(void)
         fan_control_status_known = 1;
         fan_watchdog_maxinterval = 0;
 
+        IBM_HANDLE_INIT(fans);
+        IBM_HANDLE_INIT(gfan);
+        IBM_HANDLE_INIT(sfan);
+
         if (gfan_handle) {
                 /* 570, 600e/x, 770e, 770x */
                 fan_status_access_mode = TPACPI_FAN_RD_ACPI_GFAN;
@@ -2010,7 +2064,7 @@ static int fan_init(void)
                         printk(IBM_ERR
                                "ThinkPad ACPI EC access misbehaving, "
                                "fan status and control unavailable\n");
-                        return 0;
+                        return 1;
                 }
         }
 
@@ -2041,7 +2095,9 @@ static int fan_init(void)
                 }
         }
 
-        return 0;
+        return (fan_status_access_mode != TPACPI_FAN_NONE ||
+                fan_control_access_mode != TPACPI_FAN_WR_NONE)?
+                        0 : 1;
 }
 
 static int fan_get_status(u8 *status)
@@ -2485,6 +2541,7 @@ static struct ibm_struct ibms[] = {
 #ifdef CONFIG_THINKPAD_ACPI_DOCK
         {
          .name = "dock",
+         .init = dock_init,
          .read = dock_read,
          .write = dock_write,
          .notify = dock_notify,
@@ -2512,6 +2569,7 @@ static struct ibm_struct ibms[] = {
 #endif /* CONFIG_THINKPAD_ACPI_BAY */
         {
          .name = "cmos",
+         .init = cmos_init,
          .read = cmos_read,
          .write = cmos_write,
          },
@@ -2523,6 +2581,7 @@ static struct ibm_struct ibms[] = {
          },
         {
          .name = "beep",
+         .init = beep_init,
          .read = beep_read,
          .write = beep_write,
          },
@@ -2571,20 +2630,33 @@ static int __init ibm_init(struct ibm_struct *ibm)
         if (ibm->experimental && !experimental)
                 return 0;
 
-        if (ibm->hid) {
-                ret = register_tpacpi_subdriver(ibm);
-                if (ret < 0)
-                        return ret;
-                ibm->driver_registered = 1;
-        }
-
         if (ibm->init) {
                 ret = ibm->init();
-                if (ret != 0)
+                if (ret > 0)
+                        return 0;       /* probe failed */
+                if (ret)
                         return ret;
                 ibm->init_called = 1;
         }
 
+        if (ibm->hid) {
+                ret = register_tpacpi_subdriver(ibm);
+                if (ret)
+                        goto err_out;
+        }
+
+        if (ibm->notify) {
+                ret = setup_notify(ibm);
+                if (ret == -ENODEV) {
+                        printk(IBM_NOTICE "disabling subdriver %s\n",
+                                ibm->name);
+                        ret = 0;
+                        goto err_out;
+                }
+                if (ret < 0)
+                        goto err_out;
+        }
+
         if (ibm->read) {
                 entry = create_proc_entry(ibm->name,
                                           S_IFREG | S_IRUGO | S_IWUSR,
@@ -2592,7 +2664,8 @@ static int __init ibm_init(struct ibm_struct *ibm)
                 if (!entry) {
                         printk(IBM_ERR "unable to create proc entry %s\n",
                                ibm->name);
-                        return -ENODEV;
+                        ret = -ENODEV;
+                        goto err_out;
                 }
                 entry->owner = THIS_MODULE;
                 entry->data = ibm;
@@ -2602,36 +2675,36 @@ static int __init ibm_init(struct ibm_struct *ibm)
                 ibm->proc_created = 1;
         }
 
-        if (ibm->notify) {
-                ret = setup_notify(ibm);
-                if (ret == -ENODEV) {
-                        printk(IBM_NOTICE "disabling subdriver %s\n",
-                                ibm->name);
-                        ibm_exit(ibm);
-                        return 0;
-                }
-                if (ret < 0)
-                        return ret;
-        }
-
         return 0;
+
+err_out:
+        ibm_exit(ibm);
+        return (ret < 0)? ret : 0;
 }
 
 static void ibm_exit(struct ibm_struct *ibm)
 {
-        if (ibm->notify_installed)
+        if (ibm->notify_installed) {
                 acpi_remove_notify_handler(*ibm->handle, ibm->type,
                                            dispatch_notify);
+                ibm->notify_installed = 0;
+        }
 
-        if (ibm->proc_created)
+        if (ibm->proc_created) {
                 remove_proc_entry(ibm->name, proc_dir);
-
-        if (ibm->init_called && ibm->exit)
-                ibm->exit();
+                ibm->proc_created = 0;
+        }
 
         if (ibm->driver_registered) {
                 acpi_bus_unregister_driver(ibm->driver);
                 kfree(ibm->driver);
+                ibm->driver = NULL;
+                ibm->driver_registered = 0;
+        }
+
+        if (ibm->init_called && ibm->exit) {
+                ibm->exit();
+                ibm->init_called = 0;
         }
 }
 
@@ -2663,6 +2736,32 @@ static char* __init check_dmi_for_ec(void)
         return NULL;
 }
 
+static int __init probe_for_thinkpad(void)
+{
+        int is_thinkpad;
+
+        if (acpi_disabled)
+                return -ENODEV;
+
+        /*
+         * Non-ancient models have better DMI tagging, but very old models
+         * don't.
+         */
+        is_thinkpad = dmi_name_in_vendors("ThinkPad");
+
+        /* ec is required because many other handles are relative to it */
+        IBM_HANDLE_INIT(ec);
+        if (!ec_handle) {
+                if (is_thinkpad)
+                        printk(IBM_ERR
+                                "Not yet supported ThinkPad detected!\n");
+                return -ENODEV;
+        }
+
+        return 0;
+}
+
+
 /* Module init, exit, parameters */
 
 static int __init set_ibm_param(const char *val, struct kernel_param *kp)
@@ -2712,45 +2811,13 @@ static int __init thinkpad_acpi_module_init(void)
 {
         int ret, i;
 
-        if (acpi_disabled)
-                return -ENODEV;
+        ret = probe_for_thinkpad();
+        if (ret)
+                return ret;
 
-        /* ec is required because many other handles are relative to it */
-        IBM_HANDLE_INIT(ec);
-        if (!ec_handle) {
-                printk(IBM_ERR "ec object not found\n");
-                return -ENODEV;
-        }
-
-        /* Models with newer firmware report the EC in DMI */
         ibm_thinkpad_ec_found = check_dmi_for_ec();
-
-        /* these handles are not required */
-        IBM_HANDLE_INIT(vid);
-        IBM_HANDLE_INIT(vid2);
-        IBM_HANDLE_INIT(ledb);
-        IBM_HANDLE_INIT(led);
-        IBM_HANDLE_INIT(hkey);
-        IBM_HANDLE_INIT(lght);
-        IBM_HANDLE_INIT(cmos);
-#ifdef CONFIG_THINKPAD_ACPI_DOCK
-        IBM_HANDLE_INIT(dock);
-#endif
-        IBM_HANDLE_INIT(pci);
-#ifdef CONFIG_THINKPAD_ACPI_BAY
-        IBM_HANDLE_INIT(bay);
-        if (bay_handle)
-                IBM_HANDLE_INIT(bay_ej);
-        IBM_HANDLE_INIT(bay2);
-        if (bay2_handle)
-                IBM_HANDLE_INIT(bay2_ej);
-#endif /* CONFIG_THINKPAD_ACPI_BAY */
-        IBM_HANDLE_INIT(beep);
         IBM_HANDLE_INIT(ecrd);
         IBM_HANDLE_INIT(ecwr);
-        IBM_HANDLE_INIT(fans);
-        IBM_HANDLE_INIT(gfan);
-        IBM_HANDLE_INIT(sfan);
 
         proc_dir = proc_mkdir(IBM_DIR, acpi_root_dir);
         if (!proc_dir) {
diff --git a/drivers/misc/thinkpad_acpi.h b/drivers/misc/thinkpad_acpi.h
index b2348d7a07c4..06d4c3839afd 100644
--- a/drivers/misc/thinkpad_acpi.h
+++ b/drivers/misc/thinkpad_acpi.h
@@ -104,7 +104,7 @@ static acpi_handle ecrd_handle, ecwr_handle;	/* 570 EC access */
 static acpi_handle cmos_handle, hkey_handle;    /* basic thinkpad handles */
 
 static void ibm_handle_init(char *name,
-                   acpi_handle * handle, acpi_handle parent,
+                   acpi_handle *handle, acpi_handle parent,
                    char **paths, int num_paths, char **path);
 #define IBM_HANDLE_INIT(object)                                         \
         ibm_handle_init(#object, &object##_handle, *object##_parent,    \
@@ -242,8 +242,8 @@ static int cmos_write(char *buf);
  * Dock subdriver
  */
 
-static acpi_handle pci_handle;
 #ifdef CONFIG_THINKPAD_ACPI_DOCK
+static acpi_handle pci_handle;
 static acpi_handle dock_handle;
 
 static void dock_notify(struct ibm_struct *ibm, u32 event);