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| author | Heiner Kallweit <hkallweit1@gmail.com> | 2017-03-25 14:10:08 +0100 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2017-03-30 17:31:08 +0200 |
| commit | 38ed55ca9ec2808ed7ee5183bec1f4e7187d3ea2 (patch) | |
| tree | fc9b27a32a8d92965b6853379d77effc609f4eb9 /drivers/i2c/busses/i2c-meson.c | |
| parent | e4d6bc380c9a3dd955a2c8c6c8856e913b1b42cb (diff) | |
| download | linux-38ed55ca9ec2808ed7ee5183bec1f4e7187d3ea2.tar.bz2 | |
i2c: meson: improve interrupt handler and detect spurious interrupts
If state is STATE_IDLE no interrupt should occur. Return IRQ_NONE
if such a spurious interrupt is detected.
Not having to take care of STATE_IDLE later in the interrupt handler
allows to further simplify the interrupt handler in subsequent
patches of this series.
In addition move resetting REG_CTRL_START bit to the start of the
interrupt handler to ensure that the start bit is always reset.
Currently the start bit is not reset for STATE_STOP because
i2c->state is set to STATE_IDLE.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c/busses/i2c-meson.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-meson.c | 11 |
1 files changed, 7 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-meson.c b/drivers/i2c/busses/i2c-meson.c index 0a9847c37a63..76aefd9264c2 100644 --- a/drivers/i2c/busses/i2c-meson.c +++ b/drivers/i2c/busses/i2c-meson.c @@ -231,12 +231,18 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) spin_lock(&i2c->lock); meson_i2c_reset_tokens(i2c); + meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); ctrl = readl(i2c->regs + REG_CTRL); dev_dbg(i2c->dev, "irq: state %d, pos %d, count %d, ctrl %08x\n", i2c->state, i2c->pos, i2c->count, ctrl); - if (ctrl & REG_CTRL_ERROR && i2c->state != STATE_IDLE) { + if (i2c->state == STATE_IDLE) { + spin_unlock(&i2c->lock); + return IRQ_NONE; + } + + if (ctrl & REG_CTRL_ERROR) { /* * The bit is set when the IGNORE_NAK bit is cleared * and the device didn't respond. In this case, the @@ -279,15 +285,12 @@ static irqreturn_t meson_i2c_irq(int irqno, void *dev_id) i2c->state = STATE_IDLE; complete(&i2c->done); break; - case STATE_IDLE: - break; } out: if (i2c->state != STATE_IDLE) { /* Restart the processing */ meson_i2c_write_tokens(i2c); - meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, 0); meson_i2c_set_mask(i2c, REG_CTRL, REG_CTRL_START, REG_CTRL_START); } |