rfkill: rewrite

This patch completely rewrites the rfkill core to address
the following deficiencies:

 * all rfkill drivers need to implement polling where necessary
   rather than having one central implementation

 * updating the rfkill state cannot be done from arbitrary
   contexts, forcing drivers to use schedule_work and requiring
   lots of code

 * rfkill drivers need to keep track of soft/hard blocked
   internally -- the core should do this

 * the rfkill API has many unexpected quirks, for example being
   asymmetric wrt. alloc/free and register/unregister

 * rfkill can call back into a driver from within a function the
   driver called -- this is prone to deadlocks and generally
   should be avoided

 * rfkill-input pointlessly is a separate module

 * drivers need to #ifdef rfkill functions (unless they want to
   depend on or select RFKILL) -- rfkill should provide inlines
   that do nothing if it isn't compiled in

 * the rfkill structure is not opaque -- drivers need to initialise
   it correctly (lots of sanity checking code required) -- instead
   force drivers to pass the right variables to rfkill_alloc()

 * the documentation is hard to read because it always assumes the
   reader is completely clueless and contains way TOO MANY CAPS

 * the rfkill code needlessly uses a lot of locks and atomic
   operations in locked sections

 * fix LED trigger to actually change the LED when the radio state
   changes -- this wasn't done before

Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br> [thinkpad]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 45 insertions, 114 deletions

diff --git a/drivers/platform/x86/toshiba_acpi.c b/drivers/platform/x86/toshiba_acpi.c
index 4345089f5171..81d31ea507d1 100644
--- a/drivers/platform/x86/toshiba_acpi.c
+++ b/drivers/platform/x86/toshiba_acpi.c
@@ -45,7 +45,6 @@
 #include <linux/backlight.h>
 #include <linux/platform_device.h>
 #include <linux/rfkill.h>
-#include <linux/input-polldev.h>
 
 #include <asm/uaccess.h>
 
@@ -250,21 +249,15 @@ static acpi_status hci_read2(u32 reg, u32 *out1, u32 *out2, u32 *result)
 
 struct toshiba_acpi_dev {
         struct platform_device *p_dev;
-        struct rfkill *rfk_dev;
-        struct input_polled_dev *poll_dev;
+        struct rfkill *bt_rfk;
 
         const char *bt_name;
-        const char *rfk_name;
-
-        bool last_rfk_state;
 
         struct mutex mutex;
 };
 
 static struct toshiba_acpi_dev toshiba_acpi = {
         .bt_name = "Toshiba Bluetooth",
-        .rfk_name = "Toshiba RFKill Switch",
-        .last_rfk_state = false,
 };
 
 /* Bluetooth rfkill handlers */
@@ -283,21 +276,6 @@ static u32 hci_get_bt_present(bool *present)
         return hci_result;
 }
 
-static u32 hci_get_bt_on(bool *on)
-{
-        u32 hci_result;
-        u32 value, value2;
-
-        value = 0;
-        value2 = 0x0001;
-        hci_read2(HCI_WIRELESS, &value, &value2, &hci_result);
-        if (hci_result == HCI_SUCCESS)
-                *on = (value & HCI_WIRELESS_BT_POWER) &&
-                      (value & HCI_WIRELESS_BT_ATTACH);
-
-        return hci_result;
-}
-
 static u32 hci_get_radio_state(bool *radio_state)
 {
         u32 hci_result;
@@ -311,70 +289,67 @@ static u32 hci_get_radio_state(bool *radio_state)
         return hci_result;
 }
 
-static int bt_rfkill_toggle_radio(void *data, enum rfkill_state state)
+static int bt_rfkill_set_block(void *data, bool blocked)
 {
+        struct toshiba_acpi_dev *dev = data;
         u32 result1, result2;
         u32 value;
+        int err;
         bool radio_state;
-        struct toshiba_acpi_dev *dev = data;
 
-        value = (state == RFKILL_STATE_UNBLOCKED);
+        value = (blocked == false);
 
-        if (hci_get_radio_state(&radio_state) != HCI_SUCCESS)
-                return -EFAULT;
+        mutex_lock(&dev->mutex);
+        if (hci_get_radio_state(&radio_state) != HCI_SUCCESS) {
+                err = -EBUSY;
+                goto out;
+        }
 
-        switch (state) {
-        case RFKILL_STATE_UNBLOCKED:
-                if (!radio_state)
-                        return -EPERM;
-                break;
-        case RFKILL_STATE_SOFT_BLOCKED:
-                break;
-        default:
-                return -EINVAL;
+        if (!radio_state) {
+                err = 0;
+                goto out;
         }
 
-        mutex_lock(&dev->mutex);
         hci_write2(HCI_WIRELESS, value, HCI_WIRELESS_BT_POWER, &result1);
         hci_write2(HCI_WIRELESS, value, HCI_WIRELESS_BT_ATTACH, &result2);
-        mutex_unlock(&dev->mutex);
 
         if (result1 != HCI_SUCCESS || result2 != HCI_SUCCESS)
-                return -EFAULT;
-
-        return 0;
+                err = -EBUSY;
+        else
+                err = 0;
+ out:
+        mutex_unlock(&dev->mutex);
+        return err;
 }
 
-static void bt_poll_rfkill(struct input_polled_dev *poll_dev)
+static void bt_rfkill_poll(struct rfkill *rfkill, void *data)
 {
-        bool state_changed;
         bool new_rfk_state;
         bool value;
         u32 hci_result;
-        struct toshiba_acpi_dev *dev = poll_dev->private;
+        struct toshiba_acpi_dev *dev = data;
+
+        mutex_lock(&dev->mutex);
 
         hci_result = hci_get_radio_state(&value);
-        if (hci_result != HCI_SUCCESS)
-                return; /* Can't do anything useful */
+        if (hci_result != HCI_SUCCESS) {
+                /* Can't do anything useful */
+                mutex_unlock(&dev->mutex);
+        }
 
         new_rfk_state = value;
 
-        mutex_lock(&dev->mutex);
-        state_changed = new_rfk_state != dev->last_rfk_state;
-        dev->last_rfk_state = new_rfk_state;
         mutex_unlock(&dev->mutex);
 
-        if (unlikely(state_changed)) {
-                rfkill_force_state(dev->rfk_dev,
-                                   new_rfk_state ?
-                                   RFKILL_STATE_SOFT_BLOCKED :
-                                   RFKILL_STATE_HARD_BLOCKED);
-                input_report_switch(poll_dev->input, SW_RFKILL_ALL,
-                                    new_rfk_state);
-                input_sync(poll_dev->input);
-        }
+        if (rfkill_set_hw_state(rfkill, !new_rfk_state))
+                bt_rfkill_set_block(data, true);
 }
 
+static const struct rfkill_ops toshiba_rfk_ops = {
+        .set_block = bt_rfkill_set_block,
+        .poll = bt_rfkill_poll,
+};
+
 static struct proc_dir_entry *toshiba_proc_dir /*= 0*/ ;
 static struct backlight_device *toshiba_backlight_device;
 static int force_fan;
@@ -702,14 +677,11 @@ static struct backlight_ops toshiba_backlight_data = {
 
 static void toshiba_acpi_exit(void)
 {
-        if (toshiba_acpi.poll_dev) {
-                input_unregister_polled_device(toshiba_acpi.poll_dev);
-                input_free_polled_device(toshiba_acpi.poll_dev);
+        if (toshiba_acpi.bt_rfk) {
+                rfkill_unregister(toshiba_acpi.bt_rfk);
+                rfkill_destroy(toshiba_acpi.bt_rfk);
         }
 
-        if (toshiba_acpi.rfk_dev)
-                rfkill_unregister(toshiba_acpi.rfk_dev);
-
         if (toshiba_backlight_device)
                 backlight_device_unregister(toshiba_backlight_device);
 
@@ -728,8 +700,6 @@ static int __init toshiba_acpi_init(void)
         acpi_status status = AE_OK;
         u32 hci_result;
         bool bt_present;
-        bool bt_on;
-        bool radio_on;
         int ret = 0;
 
         if (acpi_disabled)
@@ -793,60 +763,21 @@ static int __init toshiba_acpi_init(void)
 
         /* Register rfkill switch for Bluetooth */
         if (hci_get_bt_present(&bt_present) == HCI_SUCCESS && bt_present) {
-                toshiba_acpi.rfk_dev = rfkill_allocate(&toshiba_acpi.p_dev->dev,
-                                                        RFKILL_TYPE_BLUETOOTH);
-                if (!toshiba_acpi.rfk_dev) {
+                toshiba_acpi.bt_rfk = rfkill_alloc(toshiba_acpi.bt_name,
+                                                   &toshiba_acpi.p_dev->dev,
+                                                   RFKILL_TYPE_BLUETOOTH,
+                                                   &toshiba_rfk_ops,
+                                                   &toshiba_acpi);
+                if (!toshiba_acpi.bt_rfk) {
                         printk(MY_ERR "unable to allocate rfkill device\n");
                         toshiba_acpi_exit();
                         return -ENOMEM;
                 }
 
-                toshiba_acpi.rfk_dev->name = toshiba_acpi.bt_name;
-                toshiba_acpi.rfk_dev->toggle_radio = bt_rfkill_toggle_radio;
-                toshiba_acpi.rfk_dev->data = &toshiba_acpi;
-
-                if (hci_get_bt_on(&bt_on) == HCI_SUCCESS && bt_on) {
-                        toshiba_acpi.rfk_dev->state = RFKILL_STATE_UNBLOCKED;
-                } else if (hci_get_radio_state(&radio_on) == HCI_SUCCESS &&
-                           radio_on) {
-                        toshiba_acpi.rfk_dev->state = RFKILL_STATE_SOFT_BLOCKED;
-                } else {
-                        toshiba_acpi.rfk_dev->state = RFKILL_STATE_HARD_BLOCKED;
-                }
-
-                ret = rfkill_register(toshiba_acpi.rfk_dev);
+                ret = rfkill_register(toshiba_acpi.bt_rfk);
                 if (ret) {
                         printk(MY_ERR "unable to register rfkill device\n");
-                        toshiba_acpi_exit();
-                        return -ENOMEM;
-                }
-
-                /* Register input device for kill switch */
-                toshiba_acpi.poll_dev = input_allocate_polled_device();
-                if (!toshiba_acpi.poll_dev) {
-                        printk(MY_ERR
-                               "unable to allocate kill-switch input device\n");
-                        toshiba_acpi_exit();
-                        return -ENOMEM;
-                }
-                toshiba_acpi.poll_dev->private = &toshiba_acpi;
-                toshiba_acpi.poll_dev->poll = bt_poll_rfkill;
-                toshiba_acpi.poll_dev->poll_interval = 1000; /* msecs */
-
-                toshiba_acpi.poll_dev->input->name = toshiba_acpi.rfk_name;
-                toshiba_acpi.poll_dev->input->id.bustype = BUS_HOST;
-                /* Toshiba USB ID */
-                toshiba_acpi.poll_dev->input->id.vendor = 0x0930;
-                set_bit(EV_SW, toshiba_acpi.poll_dev->input->evbit);
-                set_bit(SW_RFKILL_ALL, toshiba_acpi.poll_dev->input->swbit);
-                input_report_switch(toshiba_acpi.poll_dev->input,
-                                    SW_RFKILL_ALL, TRUE);
-                input_sync(toshiba_acpi.poll_dev->input);
-
-                ret = input_register_polled_device(toshiba_acpi.poll_dev);
-                if (ret) {
-                        printk(MY_ERR
-                               "unable to register kill-switch input device\n");
+                        rfkill_destroy(toshiba_acpi.bt_rfk);
                         toshiba_acpi_exit();
                         return ret;
                 }