Re: [PATCH 32/36] usb: gadget: f_tcm: Send sense reason

Thinh Nguyen
2022-07-09T00:14:14Z

On 7/8/2022, Dmitry Bogdanov wrote:
> On Wed, Jul 06, 2022 at 04:37:43PM -0700, Thinh Nguyen wrote:
>> If there's a failure, report it back to the host with a sense reason.
>>
>> Signed-off-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
>> ---
>> drivers/usb/gadget/function/f_tcm.c | 16 +++++++++++++++-
>> 1 file changed, 15 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/gadget/function/f_tcm.c b/drivers/usb/gadget/function/f_tcm.c
>> index 7162be5fdf2f..fb9b71158c4b 100644
>> --- a/drivers/usb/gadget/function/f_tcm.c
>> +++ b/drivers/usb/gadget/function/f_tcm.c
>> @@ -669,6 +669,9 @@ static int uasp_send_read_response(struct usbg_cmd *cmd)
>> pr_err("%s(%d) => %d\n", __func__, __LINE__, ret);
>> }
>> out:
>> + if (ret)
>> + transport_send_check_condition_and_sense(&cmd->se_cmd,
>> + TCM_CHECK_CONDITION_UNIT_ATTENTION, 0);
>> return ret;
>> }
>>
>> @@ -711,6 +714,9 @@ static int uasp_send_write_request(struct usbg_cmd *cmd)
>> }
>>
>> cleanup:
>> + if (ret)
>> + transport_send_check_condition_and_sense(&cmd->se_cmd,
>> + TCM_CHECK_CONDITION_UNIT_ATTENTION, 0);
> 1. TCM_CHECK_CONDITION_UNIT_ATTENTION is used if some UA is allocated.
> You do not have UA allocated here, so that reason is not apropriate.

I see.

> 2. I am not sure that it's ok to initiate sending failure response if
> you cannot send a response right now.
> Other fabric drivers just returns -EAGAIN in case of some lack of
> resources to send a response. Then TCM Core will retry to sent that
> response again.

I'll follow with the same response then.

Thanks,
Thinh

>> return ret;
>> }
>>
>> @@ -955,7 +961,15 @@ static void usbg_data_write_cmpl(struct usb_ep *ep, struct usb_request *req)
>> return;
>>
>> cleanup:
>> - transport_generic_free_cmd(&cmd->se_cmd, 0);
>> + /* Command was aborted */
>> + if (cmd->state == UASP_QUEUE_COMMAND) {
>> + transport_generic_free_cmd(se_cmd, 0);
>> + return;
>> + }
>> +
>> + cmd->state = UASP_QUEUE_COMMAND;
>> + transport_send_check_condition_and_sense(se_cmd,
>> + TCM_CHECK_CONDITION_UNIT_ATTENTION, 0);
>> }
>>
>> static int usbg_prepare_w_request(struct usbg_cmd *cmd, struct usb_request *req)