From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FAKE_REPLY_C,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3C1ADC3F68F for ; Tue, 10 Dec 2019 23:25:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 125F2214AF for ; Tue, 10 Dec 2019 23:25:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576020338; bh=ZFu4Hwm9TXqLd33Z1de6lnSizTJgOLyN8HGrecf9HLY=; h=Date:From:To:Cc:Subject:In-Reply-To:List-ID:From; b=YnLKCHb3grC/Mb2mY4dvxfBCLiDBrPCd21j8fi3cirwRoGFpZ4h74H7PLo8T08oCw akPY9VcjoMYS44G/E9tCeUK+baj5fDjSOue01RTBsa2PRgS37YjTkqUK4jfwQErDRO hT3C9Z0AJQ1E6sc0OBgyJ2WLxNVf7G0VAD0z3Wh0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727050AbfLJXZd (ORCPT ); Tue, 10 Dec 2019 18:25:33 -0500 Received: from mail.kernel.org ([198.145.29.99]:58370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726930AbfLJXZd (ORCPT ); Tue, 10 Dec 2019 18:25:33 -0500 Received: from localhost (mobile-166-170-223-177.mycingular.net [166.170.223.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id EEC0B20663; Tue, 10 Dec 2019 23:25:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576020332; bh=ZFu4Hwm9TXqLd33Z1de6lnSizTJgOLyN8HGrecf9HLY=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=X4udzvXQ7snjmIabgtXdmw+W789EOtzVGrt2DaBfrBK0qaF4Wr94f9MMFJh+3xzvx +qQ8ecyou8iYR2vXOI5MxMI+Ryr8L3bTtQ83PA7j8M6JolUcxsGbNtz120G2bswz+g meHCfapKZI2D3fn5ZQLjpvlegaqmwITN38H8if4A= Date: Tue, 10 Dec 2019 17:25:29 -0600 From: Bjorn Helgaas To: Guenter Roeck Cc: "Enrico Weigelt, metux IT consult" , linux-kernel@vger.kernel.org, tim@buttersideup.com, james.morse@arm.com, rrichter@marvell.com, jdelvare@suse.com, miquel.raynal@bootlin.com, richard@nod.at, vigneshr@ti.com, linux-crypto@vger.kernel.org, linux-edac@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-mtd@lists.infradead.org, linux-pci@vger.kernel.org Subject: Re: [PATCH 6/6] (v3) drivers: hwmon: i5k_amb: simplify probing / device identification Message-ID: <20191210232529.GA171629@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-edac-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-edac@vger.kernel.org On Thu, Nov 28, 2019 at 06:21:31AM -0800, Guenter Roeck wrote: > On 11/28/19 4:54 AM, Enrico Weigelt, metux IT consult wrote: > > Simpilify the probing by putting all chip-specific data directly > > into the pci match table, removing the redundant chipset_ids table. > > > > Changes v3: > > * use pci_get_device_by_id() introduces by a previous patch > > of this queue > > > > Changes v2: > > * use PCI_DEVICE_DATA() macro in the pci match table > > * directly pass the pci device id to i5k_channel_probe(), > > instead of computing it internally by extra offset parameter > > > > Submitted: 2019-06-06 > > Signed-off-by: Enrico Weigelt > > I don't immediately see how this is better. I am not even sure if it > is correct. I don't mind this, but: 1) I don't maintain this file, so my opinion doesn't count much. 2) I despise the pci_get_device() interfaces because they're inefficient, not hotplug-safe, they circumvent the device model claim mechanism, and it's hard to do the reference counting correctly. 3) There are several things going on in this patch and it would be easier to read if you could split them into separate patches: - Removing the redundancy between chipset_ids[] and i5k_amb_ids[]. This seems like a nice change. - The "chipset_ids[i].fbd0 + 1" thing was weird and the new ".driver_data + 1" is still weird. Those are PCI device IDs, and addition is not a valid operation on those IDs. IMHO both PCI_DEVICE_ID_INTEL_5000_FBD0 and PCI_DEVICE_ID_INTEL_5000_FBD1 should be listed explicitly in the driver instead of trying to compute PCI_DEVICE_ID_INTEL_5000_FBD1. - Replacing the hard-coding of PCI_VENDOR_ID_INTEL with the vendor ID from i5k_amb_ids[] seems worthwhile and should be its own separate patch (if possible). - Changing to use pci_get_device_by_id(). This should be trivial to verify, like the other patches. > > --- > > drivers/hwmon/i5k_amb.c | 38 +++++++++++++++----------------------- > > 1 file changed, 15 insertions(+), 23 deletions(-) > > > > diff --git a/drivers/hwmon/i5k_amb.c b/drivers/hwmon/i5k_amb.c > > index b09c39abd3a8..cb85607d104f 100644 > > --- a/drivers/hwmon/i5k_amb.c > > +++ b/drivers/hwmon/i5k_amb.c > > @@ -414,16 +414,14 @@ static int i5k_amb_add(void) > > } > > static int i5k_find_amb_registers(struct i5k_amb_data *data, > > - unsigned long devid) > > + const struct pci_device_id *devid) > > { > > struct pci_dev *pcidev; > > u32 val32; > > int res = -ENODEV; > > /* Find AMB register memory space */ > > - pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, > > - devid, > > - NULL); > > + pcidev = pci_get_device_by_id(devid); > > if (!pcidev) > > return -ENODEV; > > @@ -447,14 +445,15 @@ static int i5k_find_amb_registers(struct i5k_amb_data *data, > > return res; > > } > > -static int i5k_channel_probe(u16 *amb_present, unsigned long dev_id) > > +static int i5k_channel_probe(u16 *amb_present, unsigned int vendor, > > + unsigned int device) > > { > > struct pci_dev *pcidev; > > u16 val16; > > int res = -ENODEV; > > /* Copy the DIMM presence map for these two channels */ > > - pcidev = pci_get_device(PCI_VENDOR_ID_INTEL, dev_id, NULL); > > + pcidev = pci_get_device(vendor, device, NULL); > > if (!pcidev) > > return -ENODEV; > > @@ -473,23 +472,12 @@ static int i5k_channel_probe(u16 *amb_present, unsigned long dev_id) > > return res; > > } > > -static struct { > > - unsigned long err; > > - unsigned long fbd0; > > -} chipset_ids[] = { > > - { PCI_DEVICE_ID_INTEL_5000_ERR, PCI_DEVICE_ID_INTEL_5000_FBD0 }, > > - { PCI_DEVICE_ID_INTEL_5400_ERR, PCI_DEVICE_ID_INTEL_5400_FBD0 }, > > - { 0, 0 } > > -}; > > - > > -#ifdef MODULE > > static const struct pci_device_id i5k_amb_ids[] = { > > - { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5000_ERR) }, > > - { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_5400_ERR) }, > > + { PCI_DEVICE_DATA(INTEL, 5000_ERR, PCI_DEVICE_ID_INTEL_5000_FBD0) }, > > + { PCI_DEVICE_DATA(INTEL, 5400_ERR, PCI_DEVICE_ID_INTEL_5400_FBD0) }, > > { 0, } > > }; > > MODULE_DEVICE_TABLE(pci, i5k_amb_ids); > > -#endif > > static int i5k_amb_probe(struct platform_device *pdev) > > { > > @@ -504,22 +492,26 @@ static int i5k_amb_probe(struct platform_device *pdev) > > /* Figure out where the AMB registers live */ > > i = 0; > > do { > > - res = i5k_find_amb_registers(data, chipset_ids[i].err); > > + res = i5k_find_amb_registers(data, &i5k_amb_ids[i]); > > if (res == 0) > > break; > > i++; > > - } while (chipset_ids[i].err); > > + } while (i5k_amb_ids[i].device); > > if (res) > > goto err; > > /* Copy the DIMM presence map for the first two channels */ > > - res = i5k_channel_probe(&data->amb_present[0], chipset_ids[i].fbd0); > > + res = i5k_channel_probe(&data->amb_present[0], > > + i5k_amb_ids[i].vendor, > > + i5k_amb_ids[i].driver_data); > > if (res) > > goto err; > > /* Copy the DIMM presence map for the optional second two channels */ > > - i5k_channel_probe(&data->amb_present[2], chipset_ids[i].fbd0 + 1); > > + i5k_channel_probe(&data->amb_present[2], > > + i5k_amb_ids[i].vendor, > > + i5k_amb_ids[i].driver_data+1); > > /* Set up resource regions */ > > reso = request_mem_region(data->amb_base, data->amb_len, DRVNAME); > > >