ARM: common: fiq_debugger: protect the uart state from the sleep timer

Change-Id: I6b834d5cab96c3466042f758feb69eae6893ec49
Signed-off-by: Dima Zavin <dima@android.com>

diff --git a/arch/arm/common/fiq_debugger.c b/arch/arm/common/fiq_debugger.c
index 7b037beb66d2605804094f939f5fc5de473f62e9..a120b75afe3d686001f53c36571b1fb1e093a6e8 100644 (file)
--- a/arch/arm/common/fiq_debugger.c
+++ b/arch/arm/common/fiq_debugger.c
@@ -73,6 +73,7 @@ struct fiq_debugger_state {
        bool debug_enable;
        bool ignore_next_wakeup_irq;
        struct timer_list sleep_timer;
+       spinlock_t sleep_timer_lock;
        bool uart_enabled;
        struct wake_lock debugger_wake_lock;
        bool console_enable;
@@ -579,7 +580,9 @@ static bool debug_exec(struct fiq_debugger_state *state,
 static void sleep_timer_expired(unsigned long data)
 {
        struct fiq_debugger_state *state = (struct fiq_debugger_state *)data;
+       unsigned long flags;
 
+       spin_lock_irqsave(&state->sleep_timer_lock, flags);
        if (state->uart_enabled && !state->no_sleep) {
                if (state->debug_enable && !state->console_enable) {
                        state->debug_enable = false;
@@ -591,10 +594,14 @@ static void sleep_timer_expired(unsigned long data)
                enable_wakeup_irq(state);
        }
        wake_unlock(&state->debugger_wake_lock);
+       spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 }
 
 static void handle_wakeup(struct fiq_debugger_state *state)
 {
+       unsigned long flags;
+
+       spin_lock_irqsave(&state->sleep_timer_lock, flags);
        if (state->wakeup_irq >= 0 && state->ignore_next_wakeup_irq) {
                state->ignore_next_wakeup_irq = false;
        } else if (!state->uart_enabled) {
@@ -604,6 +611,7 @@ static void handle_wakeup(struct fiq_debugger_state *state)
                disable_wakeup_irq(state);
                mod_timer(&state->sleep_timer, jiffies + HZ / 2);
        }
+       spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 }
 
 static irqreturn_t wakeup_irq_handler(int irq, void *dev)
@@ -621,8 +629,12 @@ static irqreturn_t wakeup_irq_handler(int irq, void *dev)
 static void debug_handle_irq_context(struct fiq_debugger_state *state)
 {
        if (!state->no_sleep) {
+               unsigned long flags;
+
+               spin_lock_irqsave(&state->sleep_timer_lock, flags);
                wake_lock(&state->debugger_wake_lock);
                mod_timer(&state->sleep_timer, jiffies + HZ * 5);
+               spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
        }
 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
        if (state->tty) {
@@ -992,6 +1004,8 @@ static int fiq_debugger_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, state);
 
+       spin_lock_init(&state->sleep_timer_lock);
+
        if (state->wakeup_irq < 0 && debug_have_fiq(state))
                state->no_sleep = true;
        state->ignore_next_wakeup_irq = !state->no_sleep;