From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752058AbbIHAad (ORCPT ); Mon, 7 Sep 2015 20:30:33 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:50384 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751197AbbIHAab (ORCPT ); Mon, 7 Sep 2015 20:30:31 -0400 Subject: Re: [PATCH] leds:lp55xx: Correct Kconfig dependency for f/w user helper To: Takashi Iwai References: <1441628701-3022-1-git-send-email-tiwai@suse.de> <55ED9CE1.1080002@samsung.com> CC: Jacek Anaszewski , , , Richard Purdie , Bryan Wu From: "Kim, Milo" Message-ID: <55EE2C0F.5040101@ti.com> Date: Tue, 8 Sep 2015 09:30:07 +0900 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.1.0 MIME-Version: 1.0 In-Reply-To: <55ED9CE1.1080002@samsung.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Takashi, On 9/7/2015 11:19 PM, Jacek Anaszewski wrote: > Hi Takashi, > > Thanks for chasing this. > Milo, could you express your opinion? > > On 09/07/2015 02:25 PM, Takashi Iwai wrote: >> The commit [b67893206fc0: leds:lp55xx: fix firmware loading error] >> tries to address the firmware file handling with user helper, but it >> sets a wrong Kconfig CONFIG_FW_LOADER_USER_HELPER_FALLBACK. Since the >> wrong option was enabled, the system got a regression -- it suffers >> from the unexpected long delays for non-present firmware files. >> >> This patch corrects the Kconfig dependency to the right one, >> CONFIG_FW_LOADER_USER_HELPER. This doesn't change the fallback >> behavior but only enables UMH when needed. >> >> Bugzilla: https://bugzilla.opensuse.org/show_bug.cgi?id=944661 >> Fixes: b67893206fc0 ('leds:lp55xx: fix firmware loading error') >> Cc: # v4.2+ >> Signed-off-by: Takashi Iwai >> --- >> drivers/leds/Kconfig | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig >> index 70f4255ff291..2ba52bc2e174 100644 >> --- a/drivers/leds/Kconfig >> +++ b/drivers/leds/Kconfig >> @@ -229,7 +229,7 @@ config LEDS_LP55XX_COMMON >> tristate "Common Driver for TI/National LP5521/5523/55231/5562/8501" >> depends on LEDS_LP5521 || LEDS_LP5523 || LEDS_LP5562 || LEDS_LP8501 >> select FW_LOADER >> - select FW_LOADER_USER_HELPER_FALLBACK >> + select FW_LOADER_USER_HELPER >> help >> This option supports common operations for LP5521/5523/55231/5562/8501 >> devices. Thank for catching this. It seems I misunderstood firmware helper configuration. LP55xx driver uses firmware interface to activate LED visual effect. So this driver enables FW_LOADER_USER_HELPER_FALLBACK and calls request_firmware_nowait() without uevent. Then, it will try to load raw data manually when binary(firmware) file doesn't exist. I'm still not clear what the difference is between FW_LOADER_USER_HELPER and FW_LOADER_USER_HELPER_FALLBACK. Kconfig description makes me confused. Could you explain it in more details? Best regards, Milo