2019-06-07 12:10:18

by Dmitry Osipenko

[permalink] [raw]
Subject: Re: [PATCH V1 6/6] i2c: tegra: remove BUG, BUG_ON

07.06.2019 14:55, Bitan Biswas пишет:
> Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
> as needed. Replace BUG() with error handling code.
> Define I2C_ERR_UNEXPECTED_STATUS for error handling.
>
> Signed-off-by: Bitan Biswas <[email protected]>
> ---
> drivers/i2c/busses/i2c-tegra.c | 15 ++++++++-------
> 1 file changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
> index 4dfb4c1..c407bd7 100644
> --- a/drivers/i2c/busses/i2c-tegra.c
> +++ b/drivers/i2c/busses/i2c-tegra.c
> @@ -73,6 +73,7 @@
> #define I2C_ERR_NO_ACK BIT(0)
> #define I2C_ERR_ARBITRATION_LOST BIT(1)
> #define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
> +#define I2C_ERR_UNEXPECTED_STATUS BIT(3)
>
> #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
> #define PACKET_HEADER0_PACKET_ID_SHIFT 16
> @@ -515,7 +516,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
> * prevent overwriting past the end of buf
> */
> if (rx_fifo_avail > 0 && buf_remaining > 0) {
> - BUG_ON(buf_remaining > 3);
> val = i2c_readl(i2c_dev, I2C_RX_FIFO);
> val = cpu_to_le32(val);
> memcpy(buf, &val, buf_remaining);
> @@ -523,7 +523,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
> rx_fifo_avail--;
> }
>
> - BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
> i2c_dev->msg_buf_remaining = buf_remaining;
> i2c_dev->msg_buf = buf;
>
> @@ -581,7 +580,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
> * boundary and fault.
> */
> if (tx_fifo_avail > 0 && buf_remaining > 0) {
> - BUG_ON(buf_remaining > 3);
> memcpy(&val, buf, buf_remaining);
> val = le32_to_cpu(val);
>
> @@ -847,10 +845,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>
> if (!i2c_dev->is_curr_dma_xfer) {
> if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
> - if (i2c_dev->msg_buf_remaining)
> + if (i2c_dev->msg_buf_remaining) {
> tegra_i2c_empty_rx_fifo(i2c_dev);
> - else
> - BUG();
> + } else {
> + dev_err(i2c_dev->dev, "unexpected rx data request\n");
> + i2c_dev->msg_err |= I2C_ERR_UNEXPECTED_STATUS;
> + goto err;
> + }
> }
>
> if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
> @@ -876,7 +877,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
> if (status & I2C_INT_PACKET_XFER_COMPLETE) {
> if (i2c_dev->is_curr_dma_xfer)
> i2c_dev->msg_buf_remaining = 0;
> - BUG_ON(i2c_dev->msg_buf_remaining);
> + WARN_ON_ONCE(i2c_dev->msg_buf_remaining);
> complete(&i2c_dev->msg_complete);
> }
> goto done;
>

Very nice, thank you very much! BTW, I think it may worth to add another
patch that will reset hardware state in a case of the warning since we
know that something gone wrong.

Reviewed-by: Dmitry Osipenko <[email protected]>


2019-06-07 12:14:40

by Dmitry Osipenko

[permalink] [raw]
Subject: Re: [PATCH V1 6/6] i2c: tegra: remove BUG, BUG_ON

07.06.2019 15:08, Dmitry Osipenko пишет:
> 07.06.2019 14:55, Bitan Biswas пишет:
>> Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
>> as needed. Replace BUG() with error handling code.
>> Define I2C_ERR_UNEXPECTED_STATUS for error handling.
>>
>> Signed-off-by: Bitan Biswas <[email protected]>
>> ---
>> drivers/i2c/busses/i2c-tegra.c | 15 ++++++++-------
>> 1 file changed, 8 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
>> index 4dfb4c1..c407bd7 100644
>> --- a/drivers/i2c/busses/i2c-tegra.c
>> +++ b/drivers/i2c/busses/i2c-tegra.c
>> @@ -73,6 +73,7 @@
>> #define I2C_ERR_NO_ACK BIT(0)
>> #define I2C_ERR_ARBITRATION_LOST BIT(1)
>> #define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
>> +#define I2C_ERR_UNEXPECTED_STATUS BIT(3)
>>
>> #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
>> #define PACKET_HEADER0_PACKET_ID_SHIFT 16
>> @@ -515,7 +516,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>> * prevent overwriting past the end of buf
>> */
>> if (rx_fifo_avail > 0 && buf_remaining > 0) {
>> - BUG_ON(buf_remaining > 3);
>> val = i2c_readl(i2c_dev, I2C_RX_FIFO);
>> val = cpu_to_le32(val);
>> memcpy(buf, &val, buf_remaining);
>> @@ -523,7 +523,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>> rx_fifo_avail--;
>> }
>>
>> - BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
>> i2c_dev->msg_buf_remaining = buf_remaining;
>> i2c_dev->msg_buf = buf;
>>
>> @@ -581,7 +580,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
>> * boundary and fault.
>> */
>> if (tx_fifo_avail > 0 && buf_remaining > 0) {
>> - BUG_ON(buf_remaining > 3);
>> memcpy(&val, buf, buf_remaining);
>> val = le32_to_cpu(val);
>>
>> @@ -847,10 +845,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>>
>> if (!i2c_dev->is_curr_dma_xfer) {
>> if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
>> - if (i2c_dev->msg_buf_remaining)
>> + if (i2c_dev->msg_buf_remaining) {
>> tegra_i2c_empty_rx_fifo(i2c_dev);
>> - else
>> - BUG();
>> + } else {
>> + dev_err(i2c_dev->dev, "unexpected rx data request\n");
>> + i2c_dev->msg_err |= I2C_ERR_UNEXPECTED_STATUS;
>> + goto err;
>> + }
>> }
>>
>> if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
>> @@ -876,7 +877,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>> if (status & I2C_INT_PACKET_XFER_COMPLETE) {
>> if (i2c_dev->is_curr_dma_xfer)
>> i2c_dev->msg_buf_remaining = 0;
>> - BUG_ON(i2c_dev->msg_buf_remaining);
>> + WARN_ON_ONCE(i2c_dev->msg_buf_remaining);
>> complete(&i2c_dev->msg_complete);
>> }
>> goto done;
>>
>
> Very nice, thank you very much! BTW, I think it may worth to add another
> patch that will reset hardware state in a case of the warning since we
> know that something gone wrong.
>
> Reviewed-by: Dmitry Osipenko <[email protected]>
>

Something like that:

complete(&i2c_dev->msg_complete);

if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
goto err;

2019-06-07 13:13:21

by Dmitry Osipenko

[permalink] [raw]
Subject: Re: [PATCH V1 6/6] i2c: tegra: remove BUG, BUG_ON

07.06.2019 15:12, Dmitry Osipenko пишет:
> 07.06.2019 15:08, Dmitry Osipenko пишет:
>> 07.06.2019 14:55, Bitan Biswas пишет:
>>> Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
>>> as needed. Replace BUG() with error handling code.
>>> Define I2C_ERR_UNEXPECTED_STATUS for error handling.
>>>
>>> Signed-off-by: Bitan Biswas <[email protected]>
>>> ---
>>> drivers/i2c/busses/i2c-tegra.c | 15 ++++++++-------
>>> 1 file changed, 8 insertions(+), 7 deletions(-)
>>>
>>> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
>>> index 4dfb4c1..c407bd7 100644
>>> --- a/drivers/i2c/busses/i2c-tegra.c
>>> +++ b/drivers/i2c/busses/i2c-tegra.c
>>> @@ -73,6 +73,7 @@
>>> #define I2C_ERR_NO_ACK BIT(0)
>>> #define I2C_ERR_ARBITRATION_LOST BIT(1)
>>> #define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
>>> +#define I2C_ERR_UNEXPECTED_STATUS BIT(3)
>>>
>>> #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
>>> #define PACKET_HEADER0_PACKET_ID_SHIFT 16
>>> @@ -515,7 +516,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>>> * prevent overwriting past the end of buf
>>> */
>>> if (rx_fifo_avail > 0 && buf_remaining > 0) {
>>> - BUG_ON(buf_remaining > 3);
>>> val = i2c_readl(i2c_dev, I2C_RX_FIFO);
>>> val = cpu_to_le32(val);
>>> memcpy(buf, &val, buf_remaining);
>>> @@ -523,7 +523,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>>> rx_fifo_avail--;
>>> }
>>>
>>> - BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
>>> i2c_dev->msg_buf_remaining = buf_remaining;
>>> i2c_dev->msg_buf = buf;
>>>
>>> @@ -581,7 +580,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
>>> * boundary and fault.
>>> */
>>> if (tx_fifo_avail > 0 && buf_remaining > 0) {
>>> - BUG_ON(buf_remaining > 3);
>>> memcpy(&val, buf, buf_remaining);
>>> val = le32_to_cpu(val);
>>>
>>> @@ -847,10 +845,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>>>
>>> if (!i2c_dev->is_curr_dma_xfer) {
>>> if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
>>> - if (i2c_dev->msg_buf_remaining)
>>> + if (i2c_dev->msg_buf_remaining) {
>>> tegra_i2c_empty_rx_fifo(i2c_dev);
>>> - else
>>> - BUG();
>>> + } else {
>>> + dev_err(i2c_dev->dev, "unexpected rx data request\n");
>>> + i2c_dev->msg_err |= I2C_ERR_UNEXPECTED_STATUS;
>>> + goto err;
>>> + }
>>> }
>>>
>>> if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
>>> @@ -876,7 +877,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>>> if (status & I2C_INT_PACKET_XFER_COMPLETE) {
>>> if (i2c_dev->is_curr_dma_xfer)
>>> i2c_dev->msg_buf_remaining = 0;
>>> - BUG_ON(i2c_dev->msg_buf_remaining);
>>> + WARN_ON_ONCE(i2c_dev->msg_buf_remaining);
>>> complete(&i2c_dev->msg_complete);
>>> }
>>> goto done;
>>>
>>
>> Very nice, thank you very much! BTW, I think it may worth to add another
>> patch that will reset hardware state in a case of the warning since we
>> know that something gone wrong.
>>
>> Reviewed-by: Dmitry Osipenko <[email protected]>
>>
>
> Something like that:
>
> complete(&i2c_dev->msg_complete);
>
> if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
> goto err;
>

Ah, that's inside the ISR, so maybe will make sense to just not complete
the transfer and let it timeout:

if (!WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
complete(&i2c_dev->msg_complete);

2019-06-07 19:05:24

by Bitan Biswas

[permalink] [raw]
Subject: Re: [PATCH V1 6/6] i2c: tegra: remove BUG, BUG_ON



On 6/7/19 5:18 AM, Dmitry Osipenko wrote:
> 07.06.2019 15:12, Dmitry Osipenko пишет:
>> 07.06.2019 15:08, Dmitry Osipenko пишет:
>>> 07.06.2019 14:55, Bitan Biswas пишет:
>>>> Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
>>>> as needed. Replace BUG() with error handling code.
>>>> Define I2C_ERR_UNEXPECTED_STATUS for error handling.
>>>>
>>>> Signed-off-by: Bitan Biswas <[email protected]>
>>>> ---
>>>> drivers/i2c/busses/i2c-tegra.c | 15 ++++++++-------
>>>> 1 file changed, 8 insertions(+), 7 deletions(-)
>>>>
>>>> diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
>>>> index 4dfb4c1..c407bd7 100644
>>>> --- a/drivers/i2c/busses/i2c-tegra.c
>>>> +++ b/drivers/i2c/busses/i2c-tegra.c
>>>> @@ -73,6 +73,7 @@
>>>> #define I2C_ERR_NO_ACK BIT(0)
>>>> #define I2C_ERR_ARBITRATION_LOST BIT(1)
>>>> #define I2C_ERR_UNKNOWN_INTERRUPT BIT(2)
>>>> +#define I2C_ERR_UNEXPECTED_STATUS BIT(3)
>>>>
>>>> #define PACKET_HEADER0_HEADER_SIZE_SHIFT 28
>>>> #define PACKET_HEADER0_PACKET_ID_SHIFT 16
>>>> @@ -515,7 +516,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>>>> * prevent overwriting past the end of buf
>>>> */
>>>> if (rx_fifo_avail > 0 && buf_remaining > 0) {
>>>> - BUG_ON(buf_remaining > 3);
>>>> val = i2c_readl(i2c_dev, I2C_RX_FIFO);
>>>> val = cpu_to_le32(val);
>>>> memcpy(buf, &val, buf_remaining);
>>>> @@ -523,7 +523,6 @@ static int tegra_i2c_empty_rx_fifo(struct tegra_i2c_dev *i2c_dev)
>>>> rx_fifo_avail--;
>>>> }
>>>>
>>>> - BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
>>>> i2c_dev->msg_buf_remaining = buf_remaining;
>>>> i2c_dev->msg_buf = buf;
>>>>
>>>> @@ -581,7 +580,6 @@ static int tegra_i2c_fill_tx_fifo(struct tegra_i2c_dev *i2c_dev)
>>>> * boundary and fault.
>>>> */
>>>> if (tx_fifo_avail > 0 && buf_remaining > 0) {
>>>> - BUG_ON(buf_remaining > 3);
>>>> memcpy(&val, buf, buf_remaining);
>>>> val = le32_to_cpu(val);
>>>>
>>>> @@ -847,10 +845,13 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>>>>
>>>> if (!i2c_dev->is_curr_dma_xfer) {
>>>> if (i2c_dev->msg_read && (status & I2C_INT_RX_FIFO_DATA_REQ)) {
>>>> - if (i2c_dev->msg_buf_remaining)
>>>> + if (i2c_dev->msg_buf_remaining) {
>>>> tegra_i2c_empty_rx_fifo(i2c_dev);
>>>> - else
>>>> - BUG();
>>>> + } else {
>>>> + dev_err(i2c_dev->dev, "unexpected rx data request\n");
>>>> + i2c_dev->msg_err |= I2C_ERR_UNEXPECTED_STATUS;
>>>> + goto err;
>>>> + }
>>>> }
>>>>
>>>> if (!i2c_dev->msg_read && (status & I2C_INT_TX_FIFO_DATA_REQ)) {
>>>> @@ -876,7 +877,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void *dev_id)
>>>> if (status & I2C_INT_PACKET_XFER_COMPLETE) {
>>>> if (i2c_dev->is_curr_dma_xfer)
>>>> i2c_dev->msg_buf_remaining = 0;
>>>> - BUG_ON(i2c_dev->msg_buf_remaining);
>>>> + WARN_ON_ONCE(i2c_dev->msg_buf_remaining);
>>>> complete(&i2c_dev->msg_complete);
>>>> }
>>>> goto done;
>>>>
>>>
>>> Very nice, thank you very much! BTW, I think it may worth to add another
>>> patch that will reset hardware state in a case of the warning since we
>>> know that something gone wrong.
>>>
>>> Reviewed-by: Dmitry Osipenko <[email protected]>
>>>
>>
>> Something like that:
>>
>> complete(&i2c_dev->msg_complete);
>>
>> if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
>> goto err;
>>
>
> Ah, that's inside the ISR, so maybe will make sense to just not complete
> the transfer and let it timeout:
>
> if (!WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
> complete(&i2c_dev->msg_complete);
OK. I shall send the updated patch.

-Thanks,
Bitan

2019-06-07 21:42:07

by Bitan Biswas

[permalink] [raw]
Subject: Re: [PATCH V1 6/6] i2c: tegra: remove BUG, BUG_ON



On 6/7/19 11:55 AM, Bitan Biswas wrote:
>
>
> On 6/7/19 5:18 AM, Dmitry Osipenko wrote:
>> 07.06.2019 15:12, Dmitry Osipenko пишет:
>>> 07.06.2019 15:08, Dmitry Osipenko пишет:
>>>> 07.06.2019 14:55, Bitan Biswas пишет:
>>>>> Remove redundant BUG_ON calls or replace with WARN_ON_ONCE
>>>>> as needed. Replace BUG() with error handling code.
>>>>> Define I2C_ERR_UNEXPECTED_STATUS for error handling.
>>>>>
>>>>> Signed-off-by: Bitan Biswas <[email protected]>
>>>>> ---
>>>>>   drivers/i2c/busses/i2c-tegra.c | 15 ++++++++-------
>>>>>   1 file changed, 8 insertions(+), 7 deletions(-)
>>>>>
>>>>> diff --git a/drivers/i2c/busses/i2c-tegra.c
>>>>> b/drivers/i2c/busses/i2c-tegra.c
>>>>> index 4dfb4c1..c407bd7 100644
>>>>> --- a/drivers/i2c/busses/i2c-tegra.c
>>>>> +++ b/drivers/i2c/busses/i2c-tegra.c
>>>>> @@ -73,6 +73,7 @@
>>>>>   #define I2C_ERR_NO_ACK                BIT(0)
>>>>>   #define I2C_ERR_ARBITRATION_LOST        BIT(1)
>>>>>   #define I2C_ERR_UNKNOWN_INTERRUPT        BIT(2)
>>>>> +#define I2C_ERR_UNEXPECTED_STATUS        BIT(3)
>>>>>   #define PACKET_HEADER0_HEADER_SIZE_SHIFT    28
>>>>>   #define PACKET_HEADER0_PACKET_ID_SHIFT        16
>>>>> @@ -515,7 +516,6 @@ static int tegra_i2c_empty_rx_fifo(struct
>>>>> tegra_i2c_dev *i2c_dev)
>>>>>        * prevent overwriting past the end of buf
>>>>>        */
>>>>>       if (rx_fifo_avail > 0 && buf_remaining > 0) {
>>>>> -        BUG_ON(buf_remaining > 3);
>>>>>           val = i2c_readl(i2c_dev, I2C_RX_FIFO);
>>>>>           val = cpu_to_le32(val);
>>>>>           memcpy(buf, &val, buf_remaining);
>>>>> @@ -523,7 +523,6 @@ static int tegra_i2c_empty_rx_fifo(struct
>>>>> tegra_i2c_dev *i2c_dev)
>>>>>           rx_fifo_avail--;
>>>>>       }
>>>>> -    BUG_ON(rx_fifo_avail > 0 && buf_remaining > 0);
>>>>>       i2c_dev->msg_buf_remaining = buf_remaining;
>>>>>       i2c_dev->msg_buf = buf;
>>>>> @@ -581,7 +580,6 @@ static int tegra_i2c_fill_tx_fifo(struct
>>>>> tegra_i2c_dev *i2c_dev)
>>>>>        * boundary and fault.
>>>>>        */
>>>>>       if (tx_fifo_avail > 0 && buf_remaining > 0) {
>>>>> -        BUG_ON(buf_remaining > 3);
>>>>>           memcpy(&val, buf, buf_remaining);
>>>>>           val = le32_to_cpu(val);
>>>>> @@ -847,10 +845,13 @@ static irqreturn_t tegra_i2c_isr(int irq,
>>>>> void *dev_id)
>>>>>       if (!i2c_dev->is_curr_dma_xfer) {
>>>>>           if (i2c_dev->msg_read && (status &
>>>>> I2C_INT_RX_FIFO_DATA_REQ)) {
>>>>> -            if (i2c_dev->msg_buf_remaining)
>>>>> +            if (i2c_dev->msg_buf_remaining) {
>>>>>                   tegra_i2c_empty_rx_fifo(i2c_dev);
>>>>> -            else
>>>>> -                BUG();
>>>>> +            } else {
>>>>> +                dev_err(i2c_dev->dev, "unexpected rx data
>>>>> request\n");
>>>>> +                i2c_dev->msg_err |= I2C_ERR_UNEXPECTED_STATUS;
>>>>> +                goto err;
>>>>> +            }
>>>>>           }
>>>>>           if (!i2c_dev->msg_read && (status &
>>>>> I2C_INT_TX_FIFO_DATA_REQ)) {
>>>>> @@ -876,7 +877,7 @@ static irqreturn_t tegra_i2c_isr(int irq, void
>>>>> *dev_id)
>>>>>       if (status & I2C_INT_PACKET_XFER_COMPLETE) {
>>>>>           if (i2c_dev->is_curr_dma_xfer)
>>>>>               i2c_dev->msg_buf_remaining = 0;
>>>>> -        BUG_ON(i2c_dev->msg_buf_remaining);
>>>>> +        WARN_ON_ONCE(i2c_dev->msg_buf_remaining);
>>>>>           complete(&i2c_dev->msg_complete);
>>>>>       }
>>>>>       goto done;
>>>>>
>>>>
>>>> Very nice, thank you very much! BTW, I think it may worth to add
>>>> another
>>>> patch that will reset hardware state in a case of the warning since we
>>>> know that something gone wrong.
>>>>
>>>> Reviewed-by: Dmitry Osipenko <[email protected]>
>>>>
>>>
>>> Something like that:
>>>
>>>       complete(&i2c_dev->msg_complete);
>>>
>>>     if (WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
>>>         goto err;
>>>
>>
>> Ah, that's inside the ISR, so maybe will make sense to just not complete
>> the transfer and let it timeout:
>>
>>     if (!WARN_ON_ONCE(i2c_dev->msg_buf_remaining))
>>         complete(&i2c_dev->msg_complete);
> OK. I shall send the updated patch.
I see that there is already err label in the ISR that could be jumped
into. Hence, planning to share updated patch with the error handling.

-regards,
Bitan