On 11/15/2014 03:12 AM, Alexander Kochetkov wrote:
commit 1d7afc95946487945cc7f5019b41255b72224b70 (i2c: omap: ack IRQ in parts)
changed the interrupt handler to complete transfers without clearing
XRDY (AL case) and ARDY (NACK case) flags. XRDY or ARDY interrupt will be
fired again (in parallel with omap_i2c_xfer_msg). Interrupt handler will
complete transfers second time. As a result, NACK and AL transfers
terminates with "transfer timeout" and sometimes client code segfault.
The patch restore original logic of handling NACK and AL interrupts and
fix race between interrupt handler and omap_i2c_xfer_msg (for AL and
NACK case only).
Tested on Beagleboard XM C.
Seems you've got the same issue as I :) long time ago
https://lkml.org/lkml/2013/6/7/530
Signed-off-by: Alexander Kochetkov <al.kochet@xxxxxxxxx>
---
drivers/i2c/busses/i2c-omap.c | 2 --
1 file changed, 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 90dcc2e..9af7095 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -926,14 +926,12 @@ omap_i2c_isr_thread(int this_irq, void *dev_id)
if (stat & OMAP_I2C_STAT_NACK) {
err |= OMAP_I2C_STAT_NACK;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_NACK);
- break;
}
if (stat & OMAP_I2C_STAT_AL) {
dev_err(dev->dev, "Arbitration lost\n");
err |= OMAP_I2C_STAT_AL;
omap_i2c_ack_stat(dev, OMAP_I2C_STAT_AL);
- break;
}
/*
--
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