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Input: tegra-kbc - tighten locking

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Take spinlock when entering ISR and timer routine to ensure that we do not
race while enabling/disabling FIFO interrupts.

Also we do not need to take teh spinlock in tegra_kbc_startremove() since
interrupt is completely disabled.

Tested-by: Rakesh Iyer <riyer@nvidia.com>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
This commit is contained in:
Dmitry Torokhov 2011-09-09 09:24:20 -07:00
parent d0d150ec28
commit 95439cbad1
1 changed files with 12 additions and 19 deletions
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31
drivers/input/keyboard/tegra-kbc.c
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@ -260,12 +260,10 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
u32 val = 0;
unsigned int i;
unsigned int num_down = 0;
unsigned long flags;
bool fn_keypress = false;
bool key_in_same_row = false;
bool key_in_same_col = false;
spin_lock_irqsave(&kbc->lock, flags);
for (i = 0; i < KBC_MAX_KPENT; i++) {
if ((i % 4) == 0)
val = readl(kbc->mmio + KBC_KP_ENT0_0 + i);
@ -294,7 +292,7 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
* any 2 of the 3 keys share a row, and any 2 of them share a column.
* If so ignore the key presses for this iteration.
*/
if ((kbc->use_ghost_filter) && (num_down >= 3)) {
if (kbc->use_ghost_filter && num_down >= 3) {
for (i = 0; i < num_down; i++) {
unsigned int j;
u8 curr_col = scancodes[i] & 0x07;
@ -327,8 +325,6 @@ static void tegra_kbc_report_keys(struct tegra_kbc *kbc)
}
}
spin_unlock_irqrestore(&kbc->lock, flags);
/* Ignore the key presses for this iteration? */
if (key_in_same_col && key_in_same_row)
return;
@ -362,6 +358,8 @@ static void tegra_kbc_keypress_timer(unsigned long data)
u32 val;
unsigned int i;
spin_lock_irqsave(&kbc->lock, flags);
val = (readl(kbc->mmio + KBC_INT_0) >> 4) & 0xf;
if (val) {
unsigned long dly;
@ -383,22 +381,19 @@ static void tegra_kbc_keypress_timer(unsigned long data)
kbc->num_pressed_keys = 0;
/* All keys are released so enable the keypress interrupt */
spin_lock_irqsave(&kbc->lock, flags);
tegra_kbc_set_fifo_interrupt(kbc, true);
spin_unlock_irqrestore(&kbc->lock, flags);
}
spin_unlock_irqrestore(&kbc->lock, flags);
}
static irqreturn_t tegra_kbc_isr(int irq, void *args)
{
struct tegra_kbc *kbc = args;
unsigned long flags;
u32 val;
/*
* Until all keys are released, defer further processing to
* the polling loop in tegra_kbc_keypress_timer
*/
tegra_kbc_set_fifo_interrupt(kbc, false);
spin_lock_irqsave(&kbc->lock, flags);
/*
* Quickly bail out & reenable interrupts if the fifo threshold
@ -409,14 +404,15 @@ static irqreturn_t tegra_kbc_isr(int irq, void *args)
if (val & KBC_INT_FIFO_CNT_INT_STATUS) {
/*
* Schedule timer to run when hardware is in continuous
* polling mode.
* Until all keys are released, defer further processing to
* the polling loop in tegra_kbc_keypress_timer.
*/
tegra_kbc_set_fifo_interrupt(kbc, false);
mod_timer(&kbc->timer, jiffies + kbc->cp_dly_jiffies);
} else {
tegra_kbc_set_fifo_interrupt(kbc, true);
}
spin_unlock_irqrestore(&kbc->lock, flags);
return IRQ_HANDLED;
}
@ -464,7 +460,6 @@ static void tegra_kbc_config_pins(struct tegra_kbc *kbc)
static int tegra_kbc_start(struct tegra_kbc *kbc)
{
const struct tegra_kbc_platform_data *pdata = kbc->pdata;
unsigned long flags;
unsigned int debounce_cnt;
u32 val = 0;
@ -502,7 +497,6 @@ static int tegra_kbc_start(struct tegra_kbc *kbc)
* Atomically clear out any remaining entries in the key FIFO
* and enable keyboard interrupts.
*/
spin_lock_irqsave(&kbc->lock, flags);
while (1) {
val = readl(kbc->mmio + KBC_INT_0);
val >>= 4;
@ -513,7 +507,6 @@ static int tegra_kbc_start(struct tegra_kbc *kbc)
val = readl(kbc->mmio + KBC_KP_ENT1_0);
}
writel(0x7, kbc->mmio + KBC_INT_0);
spin_unlock_irqrestore(&kbc->lock, flags);
enable_irq(kbc->irq);