On 2014年06月16日 10:35, Zheng, Lv wrote: > Hi, > >> From: linux-acpi-owner@xxxxxxxxxxxxxxx [mailto:linux-acpi-owner@xxxxxxxxxxxxxxx] On Behalf Of Lan Tianyu >> Sent: Monday, June 16, 2014 10:12 AM >> To: David Rientjes >> Cc: rjw@xxxxxxxxxxxxx; lenb@xxxxxxxxxx; naszar@xxxxx; linux-acpi@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx >> Subject: Re: [PATCH] ACPI/Battery: Retry to get Battery information if failed during probing >> >> On 2014年06月14日 05:46, David Rientjes wrote: >>> On Fri, 13 Jun 2014, Lan Tianyu wrote: >>> >>>> How about this? >>>> >>>> - result = acpi_battery_update(battery, false); >>>> - if (result) >>>> + >>>> + /* >>>> + * Some machines'(E,G Lenovo Z480) ECs are not stable > > Just a reminder. > > This statement may not be true. > The issue may be caused by the EC driver itself. > So we need to investigate. Not sure. The bug doesn't happen every time. 5-10% during boot up. > >>>> + * during boot up and this causes battery driver fails to be >>>> + * probed due to failure of getting battery information >>>> + * from EC sometimes. After several retries, the operation >>>> + * may work. So add retry code here and 20ms sleep between >>>> + * every retries. >>>> + */ >>>> + while (acpi_battery_update(battery, false) && retry--) > > If EC hardware is stable, why we need to do retry here? > Yes, if it can work normally every time, we don't need retry here. > Thanks and best regards > -Lv > >>>> + msleep(20); >>>> + if (!retry) { >>>> + result = -ENODEV; >>>> goto fail; >>>> + } >>>> + >>> >>> I think you want --retry and not retry--. >> >> My original purpose is to retry 5 times after the first try fails. >> If use "--retry" here, it just retries 4 times. >> >>> Otherwise it's possible for the >>> final call to acpi_battery_update() to succeed and now it's returning >>> -ENODEV. >>> >> >> Yes, it maybe and I will change code like the following. >> >> while ((result = acpi_battery_update(battery, false)) && retry--) >> msleep(20); >> if (result) >> goto fail; >> >> >> -- >> Best regards >> Tianyu Lan >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-acpi" in >> the body of a message to majordomo@xxxxxxxxxxxxxxx >> More majordomo info at http://vger.kernel.org/majordomo-info.html -- Best regards Tianyu Lan -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
