From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752203AbaIOEOK (ORCPT ); Mon, 15 Sep 2014 00:14:10 -0400 Received: from mail-pa0-f45.google.com ([209.85.220.45]:48614 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751463AbaIOEOH (ORCPT ); Mon, 15 Sep 2014 00:14:07 -0400 From: Grant Likely Subject: Re: [RFC PATCH for Juno 1/2] net: smsc911x add support for probing from ACPI To: Arnd Bergmann , linux-arm-kernel@lists.infradead.org Cc: Catalin Marinas , Hanjun Guo , Mark Rutland , "linaro-acpi@lists.linaro.org" , Will Deacon , Lv Zheng , Rob Herring , Lorenzo Pieralisi , Daniel Lezcano , Robert Moore , "linux-acpi@vger.kernel.org" , Charles Garcia-Tobin , Robert Richter , Jason Cooper , Marc Zyngier , Liviu Dudau , Mark Brown , Bjorn Helgaas , "graeme.gregory@linaro.org" , Randy Dunlap , "Rafael J. Wysocki" , "linux-kernel@vger.kernel.org" , Sudeep Holla , Olof Johansson In-Reply-To: <21764799.KDNDm9XRax@wuerfel> References: <1409583961-7466-1-git-send-email-hanjun.guo@linaro.org> <1409583961-7466-2-git-send-email-hanjun.guo@linaro.org> <20140901170447.GF608@arm.com> <21764799.KDNDm9XRax@wuerfel> Date: Sun, 14 Sep 2014 21:14:04 -0700 Message-Id: <20140915041404.A72CCC40A02@trevor.secretlab.ca> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 01 Sep 2014 19:11:44 +0200, Arnd Bergmann wrote: > On Monday 01 September 2014 18:04:47 Catalin Marinas wrote: > > On Mon, Sep 01, 2014 at 04:06:00PM +0100, Hanjun Guo wrote: > > > +#ifdef CONFIG_ACPI > > > +/* Configure some sensible defaults for ACPI mode */ > > > +static int smsc911x_probe_config_acpi(struct smsc911x_platform_config *config, > > > + acpi_handle *ahandle) > > > +{ > > > + if (!ahandle) > > > + return -ENOSYS; > > > + > > > + config->phy_interface = PHY_INTERFACE_MODE_MII; > > > + > > > + config->flags |= SMSC911X_USE_32BIT; > > > + > > > + config->irq_polarity = SMSC911X_IRQ_POLARITY_ACTIVE_HIGH; > > > + > > > + config->irq_type = SMSC911X_IRQ_TYPE_PUSH_PULL; > > > + > > > + return 0; > > > +} > > > +#else > > > > I don't like this and it shows issues we have with ACPI on certain ARM > > platforms. You hard-code these values to match the Juno platform. What > > if we get another SoC which has different configuration here? For DT, we > > have the smsc911x_probe_config_dt() which reads the relevant information > > from DT. I think this kind of configuration would be more suitable as > > _DSD properties and sharing the similar names with DT (but we go back to > > the question about who's in charge of the _DSD properties). > > Good point, I totally missed that. > > There is of course the possibility to set those values based on the > acpi_device_id, but that is exactly the part that _DSD is trying to > avoid. These are merely defaults. DSD parsing, when implemented, would be override these default values. > > > > static int smsc911x_drv_probe(struct platform_device *pdev) > > > { > > > struct device_node *np = pdev->dev.of_node; > > > + acpi_handle *ahandle = ACPI_HANDLE(&pdev->dev); > > > struct net_device *dev; > > > struct smsc911x_data *pdata; > > > struct smsc911x_platform_config *config = dev_get_platdata(&pdev->dev); > > > @@ -2436,6 +2464,9 @@ static int smsc911x_drv_probe(struct platform_device *pdev) > > > } > > > > > > retval = smsc911x_probe_config_dt(&pdata->config, np); > > > + if (retval) > > > + retval = smsc911x_probe_config_acpi(&pdata->config, ahandle); > > > + > > > > In most of the ACPI patches so far we check for ACPI first with DT as a > > fall-back if ACPI is not enabled. This changes here. > > Does this really make a difference? Nope. Only one of DT or ACPI will be matched. > > > I would prefer > > something which probes only ACPI if the ACPI is enabled (run-time, not > > config) otherwise DT only. E.g. > > (example missing?) > > I think we should have the equivalent of of_have_populated_dt(), to > check whether acpi is being used to boot, and have that new function > be hardcoded to zero in case of !IS_ENABLED(CONFIG_ACPI). The code already accounts for it. If ACPI isn't enabled, or isn't populated, then the ACPI_HANDLE macro will return NULL and the smsc911x_probe_config_acpi() function will fail. g.