Re: [PATCH V2 1/2] tty: serial: qcom_geni_serial: IRQ cleanup

[Akash Asthana <akashast@codeaurora.org>]

On 10/10/2019 7:49 PM, Stephen Boyd wrote:
> Quoting Akash Asthana (2019-10-10 02:46:03)
>> diff --git a/drivers/tty/serial/qcom_geni_serial.c b/drivers/tty/serial/qcom_geni_serial.c
>> index 14c6306..5180cd8 100644
>> --- a/drivers/tty/serial/qcom_geni_serial.c
>> +++ b/drivers/tty/serial/qcom_geni_serial.c
>> @@ -1297,11 +1291,21 @@ static int qcom_geni_serial_probe(struct platform_device *pdev)
>>          port->rx_fifo_depth = DEF_FIFO_DEPTH_WORDS;
>>          port->tx_fifo_width = DEF_FIFO_WIDTH_BITS;
>>   
>> +       scnprintf(port->name, sizeof(port->name), "qcom_geni_serial_%s%d",
>> +               (uart_console(uport) ? "console" : "uart"), uport->line);
> Drop useless parenthesis. Also, it might make more sense to make this a
> devm_kasprintf() call now.

OK

>>          irq = platform_get_irq(pdev, 0);
>>          if (irq < 0)
>>                  return irq;
>>          uport->irq = irq;
>>   
>> +       irq_set_status_flags(uport->irq, IRQ_NOAUTOEN);
> Is there a reason why we can't always leave the irq enabled and request
> it later once the uart structure has been fully initialized?

According to current design we are requesting IRQ handler in probe, and 
we enable and disable it from the startup(port open) and shutdown(port 
close) function respectively.

We need to call for disable_irq in shutdown function because client has 
closed the port and we don't expect any transfer requests after it.

>>request it later once the uart structure has been fully initialized?

     Is the ask is to move request irq later in probe after the uport is 
fully initialized?

>> +       ret = devm_request_irq(uport->dev, uport->irq, qcom_geni_serial_isr,
>> +                       IRQF_TRIGGER_HIGH, port->name, uport);
>> +       if (ret) {
>> +               dev_err(uport->dev, "Failed to get IRQ ret %d\n", ret);
>> +               return ret;
>> +       }
>> +
>>          uport->private_data = drv;
>>          platform_set_drvdata(pdev, port);
>>          port->handle_rx = console ? handle_rx_console : handle_rx_uart;

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