Re: [PATCH net-next v5 04/13] net: wwan: t7xx: Add port proxy infrastructure

["Martinez, Ricardo" <ricardo.martinez@linux.intel.com>]

On 2/25/2022 3:47 AM, Ilpo Järvinen wrote:
> On Wed, 23 Feb 2022, Ricardo Martinez wrote:
>
>> From: Haijun Liu <haijun.liu@mediatek.com>
>>
>> Port-proxy provides a common interface to interact with different types
>> of ports. Ports export their configuration via `struct t7xx_port` and
>> operate as defined by `struct port_ops`.
>>
>> Signed-off-by: Haijun Liu <haijun.liu@mediatek.com>
>> Co-developed-by: Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
>> Signed-off-by: Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
>> Co-developed-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
>> Signed-off-by: Ricardo Martinez <ricardo.martinez@linux.intel.com>
>>
>> >From a WWAN framework perspective:
>> Reviewed-by: Loic Poulain <loic.poulain@linaro.org>
>> ---
...
>> +
>> +	seq_num = FIELD_GET(CCCI_H_SEQ_FLD, le32_to_cpu(ccci_h->status));
>> +	next_seq_num = (seq_num + 1) & FIELD_MAX(CCCI_H_SEQ_FLD);
>> +	assert_bit = !!(le32_to_cpu(ccci_h->status) & CCCI_H_AST_BIT);
>> +	if (!assert_bit || port->seq_nums[MTK_RX] > FIELD_MAX(CCCI_H_SEQ_FLD))
> Is this an obfuscated way to say:
> 	... || port->seq_nums[MTK_RX] == INVALID_SEQ_NUM
> ?

Right, that condition is true only for the first packet, when seq num is 
set to INVALID_SEQ_NUM.

The next version will explicitly compare seq_nums[MTK_RX] against 
INVALID_SEQ_NUM.