From: Carlos Song <[email protected]>
A NACK flag in ISR means i2c bus error. In such condition,
there is no need to do read/write operation.
In this patch, i2c will check MSR_NDF, MSR_RDF and MSR_TDF
flag in turn, it's making mutually exclusive NACK/read/write.
So when a NACK is received(MSR_NDF), i2c will return ISR
directly and then stop i2c transfer.
Signed-off-by: Carlos Song <[email protected]>
---
drivers/i2c/busses/i2c-imx-lpi2c.c | 10 ++++------
1 file changed, 4 insertions(+), 6 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
index 150d923ca7f1..9a3e3a1bc4ee 100644
--- a/drivers/i2c/busses/i2c-imx-lpi2c.c
+++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
@@ -517,14 +517,12 @@ static irqreturn_t lpi2c_imx_isr(int irq, void *dev_id)
temp = readl(lpi2c_imx->base + LPI2C_MSR);
temp &= enabled;
- if (temp & MSR_RDF)
- lpi2c_imx_read_rxfifo(lpi2c_imx);
-
- if (temp & MSR_TDF)
- lpi2c_imx_write_txfifo(lpi2c_imx);
-
if (temp & MSR_NDF)
complete(&lpi2c_imx->complete);
+ else if (temp & MSR_RDF)
+ lpi2c_imx_read_rxfifo(lpi2c_imx);
+ else if (temp & MSR_TDF)
+ lpi2c_imx_write_txfifo(lpi2c_imx);
return IRQ_HANDLED;
}
--
2.34.1
Hi Carlos,
On Thu, Jul 27, 2023 at 11:03:47AM +0800, [email protected] wrote:
> From: Carlos Song <[email protected]>
>
> A NACK flag in ISR means i2c bus error. In such condition,
> there is no need to do read/write operation.
>
> In this patch, i2c will check MSR_NDF, MSR_RDF and MSR_TDF
> flag in turn, it's making mutually exclusive NACK/read/write.
> So when a NACK is received(MSR_NDF), i2c will return ISR
> directly and then stop i2c transfer.
>
> Signed-off-by: Carlos Song <[email protected]>
thanks!
Reviewed-by: Andi Shyti <[email protected]>
Andi
Hi
On Thu, 27 Jul 2023 11:03:47 +0800, [email protected] wrote:
> A NACK flag in ISR means i2c bus error. In such condition,
> there is no need to do read/write operation.
>
> In this patch, i2c will check MSR_NDF, MSR_RDF and MSR_TDF
> flag in turn, it's making mutually exclusive NACK/read/write.
> So when a NACK is received(MSR_NDF), i2c will return ISR
> directly and then stop i2c transfer.
>
> [...]
Applied to i2c/andi-for-next on
https://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux.git
Please note that this patch may still undergo further evaluation
and the final decision will be made in collaboration with
Wolfram.
Thank you,
Andi
Patches applied
===============
[1/1] i2c: imx-lpi2c: directly return ISR when detect a NACK
commit: 7525bcc34ec49a39e8b56f5911431a5a2a981896
On Wed, Aug 02, 2023 at 10:10:31PM +0200, Andi Shyti wrote:
> Hi
>
> On Thu, 27 Jul 2023 11:03:47 +0800, [email protected] wrote:
> > A NACK flag in ISR means i2c bus error. In such condition,
> > there is no need to do read/write operation.
> >
> > In this patch, i2c will check MSR_NDF, MSR_RDF and MSR_TDF
> > flag in turn, it's making mutually exclusive NACK/read/write.
> > So when a NACK is received(MSR_NDF), i2c will return ISR
> > directly and then stop i2c transfer.
> >
> > [...]
>
> Applied to i2c/andi-for-next on
Applied to for-next (via Andi's tree), thanks!