From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751857AbbGOCm3 (ORCPT ); Tue, 14 Jul 2015 22:42:29 -0400 Received: from mail-wg0-f45.google.com ([74.125.82.45]:34450 "EHLO mail-wg0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751189AbbGOCm2 (ORCPT ); Tue, 14 Jul 2015 22:42:28 -0400 MIME-Version: 1.0 In-Reply-To: <55A5B16F.9000003@samsung.com> References: <1436888477-3841-1-git-send-email-linux.amoon@gmail.com> <55A5B16F.9000003@samsung.com> From: Anand Moon Date: Wed, 15 Jul 2015 08:12:07 +0530 Message-ID: Subject: Re: [PATCHv2] regulator: s2mps11: Added shutdown function to poweroff To: Krzysztof Kozlowski Cc: Sangbeom Kim , Marek Szyprowski , Liam Girdwood , Mark Brown , Linux Kernel , "linux-samsung-soc@vger.kernel.org" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi Krzysztof, On 15 July 2015 at 06:33, Krzysztof Kozlowski wrote: > On 15.07.2015 00:41, Anand Moon wrote: >> Added .shutdown function to s2mps11 to help poweroff the board successfully. > > Which board does not poweroff? The PMIC is used on multiple boards, did > you observed this on all of them? > >> >> s2mps11-pmic: S2MPS11_REG_CTRL1 reg value 16:00000000000000000000000000010000 >> >> The device driver clears the register to turn off the PMIC. > > This is not sufficient explanation for commit message. > > I already raised concerns that this does not look to me as a proper way > of doing poweroff. Unfortunately you did not resolved these concerns. > > The main questions are unanswered: Why you have to do this and why > "standard" way does not work? > How can you properly fix some problem if you don't know the cause of > problem? It is blind shooting which may hurt other boards. > > >> >> Signed-off-by: Anand Moon >> >> --- >> Console log for improper shutdown. >> root@odroidxu3:~# poweroff >> ... >> * Unmounting temporary filesystems... [ OK ] >> * Deactivating swap... [ OK ] >> * Unmounting local filesystems... [ OK ] >> * Will now halt >> [ 209.020280] reboot: Power down >> [ 209.122039] Power down failed, please power off system manually. >> >> Console log for proper shutdown. >> root@odroidxu3:~# poweroff >> ... >> * Unmounting temporary filesystems... [ OK ] >> * Deactivating swap... [ OK ] >> * Unmounting local filesystems... [ OK ] >> * Will now halt >> [ 476.283071] reboo >> --- >> drivers/regulator/s2mps11.c | 26 ++++++++++++++++++++++++++ >> 1 file changed, 26 insertions(+) >> >> diff --git a/drivers/regulator/s2mps11.c b/drivers/regulator/s2mps11.c >> index 326ffb5..823180e 100644 >> --- a/drivers/regulator/s2mps11.c >> +++ b/drivers/regulator/s2mps11.c >> @@ -1060,6 +1060,31 @@ out: >> return ret; >> } >> >> +static void s2mps11_pmic_shutdown(struct platform_device *pdev) >> +{ >> + struct sec_pmic_dev *iodev = dev_get_drvdata(pdev->dev.parent); >> + unsigned int reg_val, ret; >> + >> + ret = regmap_read(iodev->regmap_pmic, S2MPS11_REG_CTRL1, ®_val); >> + if (ret < 0) { > > regmap_read() returns an int which you assign to an unsigned int which > then you compare against <0? This does not look good. > >> + dev_crit(&pdev->dev, "could not read S2MPS11_REG_CTRL1 value\n"); >> + } else { >> + /* >> + * s2mps11-pmic: S2MPS11_REG_CTRL1 reg value >> + * is 00000000000000000000000000010000 >> + * clear the S2MPS11_REG_CTRL1 0x10 value to shutdown. >> + */ >> + if (reg_val & BIT(4)) { >> + ret = regmap_update_bits(iodev->regmap_pmic, >> + S2MPS11_REG_CTRL1, >> + BIT(4), BIT(0)); > > I don't understand. You want to update BIT(4) but the value is BIT(0)? > This will clear BIT(4) but is totally unreadable. > >> + if (ret) >> + dev_crit(&pdev->dev, >> + "could not write S2MPS11_REG_CTRL1 value\n"); >> + } >> + } > > The code is not readable, to many unnecessary indentations. > >> +} >> + >> static const struct platform_device_id s2mps11_pmic_id[] = { >> { "s2mps11-pmic", S2MPS11X}, >> { "s2mps13-pmic", S2MPS13X}, >> @@ -1074,6 +1099,7 @@ static struct platform_driver s2mps11_pmic_driver = { >> .name = "s2mps11-pmic", >> }, >> .probe = s2mps11_pmic_probe, >> + .shutdown = s2mps11_pmic_shutdown, > > The purpose of shutdown function is not to shutdown the system but to > prepare the system for shutdown. > > The patch is just wrong and you did not answered the major question - > WHY you have to do this? Don't fix the problem blindly (or because some > hardkernel tree for some of the boards use such patch). > > Best regards, > Krzysztof > >> .id_table = s2mps11_pmic_id, >> }; >> >> > I might me missing the bigger picture. So drop it. -Anand Moon