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, 22 insertions, 20 deletions

diff --git a/drivers/net/usb/hso.c b/drivers/net/usb/hso.c
index 837135f0390a..5ddd8c4f9019 100644
--- a/drivers/net/usb/hso.c
+++ b/drivers/net/usb/hso.c
@@ -2481,10 +2481,10 @@ static int add_net_device(struct hso_device *hso_dev)
         return 0;
 }
 
-static int hso_radio_toggle(void *data, enum rfkill_state state)
+static int hso_rfkill_set_block(void *data, bool blocked)
 {
         struct hso_device *hso_dev = data;
-        int enabled = (state == RFKILL_STATE_UNBLOCKED);
+        int enabled = !blocked;
         int rv;
 
         mutex_lock(&hso_dev->mutex);
@@ -2498,6 +2498,10 @@ static int hso_radio_toggle(void *data, enum rfkill_state state)
         return rv;
 }
 
+static const struct rfkill_ops hso_rfkill_ops = {
+        .set_block = hso_rfkill_set_block,
+};
+
 /* Creates and sets up everything for rfkill */
 static void hso_create_rfkill(struct hso_device *hso_dev,
                              struct usb_interface *interface)
@@ -2506,29 +2510,25 @@ static void hso_create_rfkill(struct hso_device *hso_dev,
         struct device *dev = &hso_net->net->dev;
         char *rfkn;
 
-        hso_net->rfkill = rfkill_allocate(&interface_to_usbdev(interface)->dev,
-                                 RFKILL_TYPE_WWAN);
-        if (!hso_net->rfkill) {
-                dev_err(dev, "%s - Out of memory\n", __func__);
-                return;
-        }
         rfkn = kzalloc(20, GFP_KERNEL);
-        if (!rfkn) {
-                rfkill_free(hso_net->rfkill);
-                hso_net->rfkill = NULL;
+        if (!rfkn)
                 dev_err(dev, "%s - Out of memory\n", __func__);
-                return;
-        }
+
         snprintf(rfkn, 20, "hso-%d",
                  interface->altsetting->desc.bInterfaceNumber);
-        hso_net->rfkill->name = rfkn;
-        hso_net->rfkill->state = RFKILL_STATE_UNBLOCKED;
-        hso_net->rfkill->data = hso_dev;
-        hso_net->rfkill->toggle_radio = hso_radio_toggle;
+
+        hso_net->rfkill = rfkill_alloc(rfkn,
+                                       &interface_to_usbdev(interface)->dev,
+                                       RFKILL_TYPE_WWAN,
+                                       &hso_rfkill_ops, hso_dev);
+        if (!hso_net->rfkill) {
+                dev_err(dev, "%s - Out of memory\n", __func__);
+                kfree(rfkn);
+                return;
+        }
         if (rfkill_register(hso_net->rfkill) < 0) {
+                rfkill_destroy(hso_net->rfkill);
                 kfree(rfkn);
-                hso_net->rfkill->name = NULL;
-                rfkill_free(hso_net->rfkill);
                 hso_net->rfkill = NULL;
                 dev_err(dev, "%s - Failed to register rfkill\n", __func__);
                 return;
@@ -3165,8 +3165,10 @@ static void hso_free_interface(struct usb_interface *interface)
                         hso_stop_net_device(network_table[i]);
                         cancel_work_sync(&network_table[i]->async_put_intf);
                         cancel_work_sync(&network_table[i]->async_get_intf);
-                        if (rfk)
+                        if (rfk) {
                                 rfkill_unregister(rfk);
+                                rfkill_destroy(rfk);
+                        }
                         hso_free_net_device(network_table[i]);
                 }
         }