| Message ID | 1416013976-6441-1-git-send-email-al.kochet@gmail.com |
|---|---|
| State | Superseded |
| Headers | show |
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@gmail.com> > --- > 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; > } > > /* > -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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; } /*
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. Signed-off-by: Alexander Kochetkov <al.kochet@gmail.com> --- drivers/i2c/busses/i2c-omap.c | 2 -- 1 file changed, 2 deletions(-)