From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932954AbcFUHZu (ORCPT ); Tue, 21 Jun 2016 03:25:50 -0400 Received: from mail-pa0-f66.google.com ([209.85.220.66]:34347 "EHLO mail-pa0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754460AbcFUHYY (ORCPT ); Tue, 21 Jun 2016 03:24:24 -0400 From: Andrey Smirnov To: rtc-linux@googlegroups.com Cc: Andrey Smirnov , Alessandro Zummo , Alexandre Belloni , linux-kernel@vger.kernel.org, cphealy@gmail.com Subject: [PATCH v2 15/17] RTC: rtctest: Change alarm IRQ support detection Date: Tue, 21 Jun 2016 00:22:48 -0700 Message-Id: <1466493770-11895-14-git-send-email-andrew.smirnov@gmail.com> X-Mailer: git-send-email 2.5.5 In-Reply-To: <1466493770-11895-1-git-send-email-andrew.smirnov@gmail.com> References: <1466493770-11895-1-git-send-email-andrew.smirnov@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org For old style drivers, call a call to ioctl(..., RTC_ALM_SET, ...): - char/ds1302.c will always return -EINVAL - char/genrtc.c: will always return -EINVAL - char/rtc.c will succeed regardless if IRQs are supported or not - char/efirtc.c will always return -EINVAL - input/misc/hp_sdc_rtc.c ... that ioctl code is a good lesson about ifdefing code out and punting implementation ... and it will always return -EINVAL For new style rtc drivers, a call to ioctl(..., RTC_ALM_SET, ...) never results in a call to __rtc_set_alarm, since struct rtc_wkalarm passed to rtc_set_alarm has 'enabled' field set to 0. This means that rtc->ops->set_alarm driver hook is never called in that ioctl. Since no driver code interaction happens as a part of that call, using its results to ascertain properties of the driver is not going to work. To remedy this - use the result of RTC_AIE_ON to make the judgement. This patch also changes ENOTTY to EINVAL as a error code value that would tell us that IRQs are not supported. There are three reason for this: - As mentioned above old style driver never retunr ENOTTY for this ioctl - In it's code __rtc_set_alarm() returns -EINVAL if rtc->ops->set_alarm method is not provided by the driver, so one reason for change is to be consistent with that code path. - A call to ioctl(..., RTC_UIE_ON, ...) will result in a call to rtc_update_irq_enable() and then __rtc_set_alarm(), which, if IRQs are not supported by the driver, will result in a non-zero error code. Returning ENOTTY in that case would: a) Not be consistent with other codepaths of rtc_update_irq_enable, for example the check of rtc->uie_unsupported b) Would break update IRQ emulation code since that codpath expects EINVAL c) Would break test's logic for feature support detection in the case of RTC_UIE_ON ioctl Signed-off-by: Andrey Smirnov --- tools/testing/selftests/timers/rtctest.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/timers/rtctest.c b/tools/testing/selftests/timers/rtctest.c index 624bce5..0cb4628 100644 --- a/tools/testing/selftests/timers/rtctest.c +++ b/tools/testing/selftests/timers/rtctest.c @@ -144,11 +144,12 @@ test_READ: retval = ioctl(fd, RTC_ALM_SET, &rtc_tm); if (retval == -1) { - if (errno == ENOTTY) { + if (errno == EINVAL) { fprintf(stderr, "\n...Alarm IRQs not supported.\n"); goto test_PIE; } + perror("RTC_ALM_SET ioctl"); exit(errno); } @@ -166,6 +167,12 @@ test_READ: /* Enable alarm interrupts */ retval = ioctl(fd, RTC_AIE_ON, 0); if (retval == -1) { + if (errno == EINVAL) { + fprintf(stderr, + "\n...Alarm IRQs not supported.\n"); + goto test_PIE; + } + perror("RTC_AIE_ON ioctl"); exit(errno); } -- 2.5.5