[PATCH 4.9 108/148] i2c: riic: fix restart condition

Greg Kroah-Hartman
2017-12-12T12:59:49Z

From: Chris Brandt <chris.brandt@renesas.com>

[ Upstream commit 2501c1bb054290679baad0ff7f4f07c714251f4c ]

While modifying the driver to use the STOP interrupt, the completion of the
intermediate transfers need to wake the driver back up in order to initiate
the next transfer (restart condition). Otherwise you get never ending
interrupts and only the first transfer sent.

Fixes: 71ccea095ea1 ("i2c: riic: correctly finish transfers")
Reported-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Chris Brandt <chris.brandt@renesas.com>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/i2c/busses/i2c-riic.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

--- a/drivers/i2c/busses/i2c-riic.c
+++ b/drivers/i2c/busses/i2c-riic.c
@@ -218,8 +218,12 @@ static irqreturn_t riic_tend_isr(int irq
}

if (riic->is_last || riic->err) {
- riic_clear_set_bit(riic, 0, ICIER_SPIE, RIIC_ICIER);
+ riic_clear_set_bit(riic, ICIER_TEIE, ICIER_SPIE, RIIC_ICIER);
writeb(ICCR2_SP, riic->base + RIIC_ICCR2);
+ } else {
+ /* Transfer is complete, but do not send STOP */
+ riic_clear_set_bit(riic, ICIER_TEIE, 0, RIIC_ICIER);
+ complete(&riic->msg_done);
}

return IRQ_HANDLED;