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authorJohannes Berg <johannes@sipsolutions.net>2009-06-02 13:01:37 +0200
committerJohn W. Linville <linville@tuxdriver.com>2009-06-03 14:06:13 -0400
commit19d337dff95cbf76edd3ad95c0cee2732c3e1ec5 (patch)
tree33326eeb09cb9664cc8427a5dc7cd2b08b5a57c3 /net/rfkill/input.c
parent0f6399c4c525b518644a9b09f8d6fb125a418c4d (diff)
downloadlinux-stericsson-19d337dff95cbf76edd3ad95c0cee2732c3e1ec5.tar.gz
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>
Diffstat (limited to 'net/rfkill/input.c')
-rw-r--r--net/rfkill/input.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/net/rfkill/input.c b/net/rfkill/input.c
new file mode 100644
index 000000000000..a7295ad5f9cb
--- /dev/null
+++ b/net/rfkill/input.c
@@ -0,0 +1,342 @@
+/*
+ * Input layer to RF Kill interface connector
+ *
+ * Copyright (c) 2007 Dmitry Torokhov
+ * Copyright 2009 Johannes Berg <johannes@sipsolutions.net>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published
+ * by the Free Software Foundation.
+ *
+ * If you ever run into a situation in which you have a SW_ type rfkill
+ * input device, then you can revive code that was removed in the patch
+ * "rfkill-input: remove unused code".
+ */
+
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/workqueue.h>
+#include <linux/init.h>
+#include <linux/rfkill.h>
+#include <linux/sched.h>
+
+#include "rfkill.h"
+
+enum rfkill_input_master_mode {
+ RFKILL_INPUT_MASTER_UNLOCK = 0,
+ RFKILL_INPUT_MASTER_RESTORE = 1,
+ RFKILL_INPUT_MASTER_UNBLOCKALL = 2,
+ NUM_RFKILL_INPUT_MASTER_MODES
+};
+
+/* Delay (in ms) between consecutive switch ops */
+#define RFKILL_OPS_DELAY 200
+
+static enum rfkill_input_master_mode rfkill_master_switch_mode =
+ RFKILL_INPUT_MASTER_UNBLOCKALL;
+module_param_named(master_switch_mode, rfkill_master_switch_mode, uint, 0);
+MODULE_PARM_DESC(master_switch_mode,
+ "SW_RFKILL_ALL ON should: 0=do nothing (only unlock); 1=restore; 2=unblock all");
+
+static spinlock_t rfkill_op_lock;
+static bool rfkill_op_pending;
+static unsigned long rfkill_sw_pending[BITS_TO_LONGS(NUM_RFKILL_TYPES)];
+static unsigned long rfkill_sw_state[BITS_TO_LONGS(NUM_RFKILL_TYPES)];
+
+enum rfkill_sched_op {
+ RFKILL_GLOBAL_OP_EPO = 0,
+ RFKILL_GLOBAL_OP_RESTORE,
+ RFKILL_GLOBAL_OP_UNLOCK,
+ RFKILL_GLOBAL_OP_UNBLOCK,
+};
+
+static enum rfkill_sched_op rfkill_master_switch_op;
+static enum rfkill_sched_op rfkill_op;
+
+static void __rfkill_handle_global_op(enum rfkill_sched_op op)
+{
+ unsigned int i;
+
+ switch (op) {
+ case RFKILL_GLOBAL_OP_EPO:
+ rfkill_epo();
+ break;
+ case RFKILL_GLOBAL_OP_RESTORE:
+ rfkill_restore_states();
+ break;
+ case RFKILL_GLOBAL_OP_UNLOCK:
+ rfkill_remove_epo_lock();
+ break;
+ case RFKILL_GLOBAL_OP_UNBLOCK:
+ rfkill_remove_epo_lock();
+ for (i = 0; i < NUM_RFKILL_TYPES; i++)
+ rfkill_switch_all(i, false);
+ break;
+ default:
+ /* memory corruption or bug, fail safely */
+ rfkill_epo();
+ WARN(1, "Unknown requested operation %d! "
+ "rfkill Emergency Power Off activated\n",
+ op);
+ }
+}
+
+static void __rfkill_handle_normal_op(const enum rfkill_type type,
+ const bool complement)
+{
+ bool blocked;
+
+ blocked = rfkill_get_global_sw_state(type);
+ if (complement)
+ blocked = !blocked;
+
+ rfkill_switch_all(type, blocked);
+}
+
+static void rfkill_op_handler(struct work_struct *work)
+{
+ unsigned int i;
+ bool c;
+
+ spin_lock_irq(&rfkill_op_lock);
+ do {
+ if (rfkill_op_pending) {
+ enum rfkill_sched_op op = rfkill_op;
+ rfkill_op_pending = false;
+ memset(rfkill_sw_pending, 0,
+ sizeof(rfkill_sw_pending));
+ spin_unlock_irq(&rfkill_op_lock);
+
+ __rfkill_handle_global_op(op);
+
+ spin_lock_irq(&rfkill_op_lock);
+
+ /*
+ * handle global ops first -- during unlocked period
+ * we might have gotten a new global op.
+ */
+ if (rfkill_op_pending)
+ continue;
+ }
+
+ if (rfkill_is_epo_lock_active())
+ continue;
+
+ for (i = 0; i < NUM_RFKILL_TYPES; i++) {
+ if (__test_and_clear_bit(i, rfkill_sw_pending)) {
+ c = __test_and_clear_bit(i, rfkill_sw_state);
+ spin_unlock_irq(&rfkill_op_lock);
+
+ __rfkill_handle_normal_op(i, c);
+
+ spin_lock_irq(&rfkill_op_lock);
+ }
+ }
+ } while (rfkill_op_pending);
+ spin_unlock_irq(&rfkill_op_lock);
+}
+
+static DECLARE_DELAYED_WORK(rfkill_op_work, rfkill_op_handler);
+static unsigned long rfkill_last_scheduled;
+
+static unsigned long rfkill_ratelimit(const unsigned long last)
+{
+ const unsigned long delay = msecs_to_jiffies(RFKILL_OPS_DELAY);
+ return (time_after(jiffies, last + delay)) ? 0 : delay;
+}
+
+static void rfkill_schedule_ratelimited(void)
+{
+ if (delayed_work_pending(&rfkill_op_work))
+ return;
+ schedule_delayed_work(&rfkill_op_work,
+ rfkill_ratelimit(rfkill_last_scheduled));
+ rfkill_last_scheduled = jiffies;
+}
+
+static void rfkill_schedule_global_op(enum rfkill_sched_op op)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&rfkill_op_lock, flags);
+ rfkill_op = op;
+ rfkill_op_pending = true;
+ if (op == RFKILL_GLOBAL_OP_EPO && !rfkill_is_epo_lock_active()) {
+ /* bypass the limiter for EPO */
+ cancel_delayed_work(&rfkill_op_work);
+ schedule_delayed_work(&rfkill_op_work, 0);
+ rfkill_last_scheduled = jiffies;
+ } else
+ rfkill_schedule_ratelimited();
+ spin_unlock_irqrestore(&rfkill_op_lock, flags);
+}
+
+static void rfkill_schedule_toggle(enum rfkill_type type)
+{
+ unsigned long flags;
+
+ if (rfkill_is_epo_lock_active())
+ return;
+
+ spin_lock_irqsave(&rfkill_op_lock, flags);
+ if (!rfkill_op_pending) {
+ __set_bit(type, rfkill_sw_pending);
+ __change_bit(type, rfkill_sw_state);
+ rfkill_schedule_ratelimited();
+ }
+ spin_unlock_irqrestore(&rfkill_op_lock, flags);
+}
+
+static void rfkill_schedule_evsw_rfkillall(int state)
+{
+ if (state)
+ rfkill_schedule_global_op(rfkill_master_switch_op);
+ else
+ rfkill_schedule_global_op(RFKILL_GLOBAL_OP_EPO);
+}
+
+static void rfkill_event(struct input_handle *handle, unsigned int type,
+ unsigned int code, int data)
+{
+ if (type == EV_KEY && data == 1) {
+ switch (code) {
+ case KEY_WLAN:
+ rfkill_schedule_toggle(RFKILL_TYPE_WLAN);
+ break;
+ case KEY_BLUETOOTH:
+ rfkill_schedule_toggle(RFKILL_TYPE_BLUETOOTH);
+ break;
+ case KEY_UWB:
+ rfkill_schedule_toggle(RFKILL_TYPE_UWB);
+ break;
+ case KEY_WIMAX:
+ rfkill_schedule_toggle(RFKILL_TYPE_WIMAX);
+ break;
+ }
+ } else if (type == EV_SW && code == SW_RFKILL_ALL)
+ rfkill_schedule_evsw_rfkillall(data);
+}
+
+static int rfkill_connect(struct input_handler *handler, struct input_dev *dev,
+ const struct input_device_id *id)
+{
+ struct input_handle *handle;
+ int error;
+
+ handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
+ if (!handle)
+ return -ENOMEM;
+
+ handle->dev = dev;
+ handle->handler = handler;
+ handle->name = "rfkill";
+
+ /* causes rfkill_start() to be called */
+ error = input_register_handle(handle);
+ if (error)
+ goto err_free_handle;
+
+ error = input_open_device(handle);
+ if (error)
+ goto err_unregister_handle;
+
+ return 0;
+
+ err_unregister_handle:
+ input_unregister_handle(handle);
+ err_free_handle:
+ kfree(handle);
+ return error;
+}
+
+static void rfkill_start(struct input_handle *handle)
+{
+ /*
+ * Take event_lock to guard against configuration changes, we
+ * should be able to deal with concurrency with rfkill_event()
+ * just fine (which event_lock will also avoid).
+ */
+ spin_lock_irq(&handle->dev->event_lock);
+
+ if (test_bit(EV_SW, handle->dev->evbit) &&
+ test_bit(SW_RFKILL_ALL, handle->dev->swbit))
+ rfkill_schedule_evsw_rfkillall(test_bit(SW_RFKILL_ALL,
+ handle->dev->sw));
+
+ spin_unlock_irq(&handle->dev->event_lock);
+}
+
+static void rfkill_disconnect(struct input_handle *handle)
+{
+ input_close_device(handle);
+ input_unregister_handle(handle);
+ kfree(handle);
+}
+
+static const struct input_device_id rfkill_ids[] = {
+ {
+ .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
+ .evbit = { BIT_MASK(EV_KEY) },
+ .keybit = { [BIT_WORD(KEY_WLAN)] = BIT_MASK(KEY_WLAN) },
+ },
+ {
+ .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
+ .evbit = { BIT_MASK(EV_KEY) },
+ .keybit = { [BIT_WORD(KEY_BLUETOOTH)] = BIT_MASK(KEY_BLUETOOTH) },
+ },
+ {
+ .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
+ .evbit = { BIT_MASK(EV_KEY) },
+ .keybit = { [BIT_WORD(KEY_UWB)] = BIT_MASK(KEY_UWB) },
+ },
+ {
+ .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_KEYBIT,
+ .evbit = { BIT_MASK(EV_KEY) },
+ .keybit = { [BIT_WORD(KEY_WIMAX)] = BIT_MASK(KEY_WIMAX) },
+ },
+ {
+ .flags = INPUT_DEVICE_ID_MATCH_EVBIT | INPUT_DEVICE_ID_MATCH_SWBIT,
+ .evbit = { BIT(EV_SW) },
+ .swbit = { [BIT_WORD(SW_RFKILL_ALL)] = BIT_MASK(SW_RFKILL_ALL) },
+ },
+ { }
+};
+
+static struct input_handler rfkill_handler = {
+ .name = "rfkill",
+ .event = rfkill_event,
+ .connect = rfkill_connect,
+ .start = rfkill_start,
+ .disconnect = rfkill_disconnect,
+ .id_table = rfkill_ids,
+};
+
+int __init rfkill_handler_init(void)
+{
+ switch (rfkill_master_switch_mode) {
+ case RFKILL_INPUT_MASTER_UNBLOCKALL:
+ rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNBLOCK;
+ break;
+ case RFKILL_INPUT_MASTER_RESTORE:
+ rfkill_master_switch_op = RFKILL_GLOBAL_OP_RESTORE;
+ break;
+ case RFKILL_INPUT_MASTER_UNLOCK:
+ rfkill_master_switch_op = RFKILL_GLOBAL_OP_UNLOCK;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spin_lock_init(&rfkill_op_lock);
+
+ /* Avoid delay at first schedule */
+ rfkill_last_scheduled =
+ jiffies - msecs_to_jiffies(RFKILL_OPS_DELAY) - 1;
+ return input_register_handler(&rfkill_handler);
+}
+
+void __exit rfkill_handler_exit(void)
+{
+ input_unregister_handler(&rfkill_handler);
+ cancel_delayed_work_sync(&rfkill_op_work);
+}