From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965318AbbLWSth (ORCPT ); Wed, 23 Dec 2015 13:49:37 -0500 Received: from mail-yk0-f182.google.com ([209.85.160.182]:34801 "EHLO mail-yk0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932075AbbLWStd convert rfc822-to-8bit (ORCPT ); Wed, 23 Dec 2015 13:49:33 -0500 MIME-Version: 1.0 In-Reply-To: <1450880383-29560-2-git-send-email-aleksey.makarov@linaro.org> References: <1450880383-29560-1-git-send-email-aleksey.makarov@linaro.org> <1450880383-29560-2-git-send-email-aleksey.makarov@linaro.org> Date: Wed, 23 Dec 2015 20:49:33 +0200 Message-ID: Subject: Re: [PATCH v4 1/3] ACPI: amba bus probing support From: Andy Shevchenko To: Aleksey Makarov Cc: "linux-acpi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-serial@vger.kernel.org" , linux-arm Mailing List , Graeme Gregory , Russell King , Greg Kroah-Hartman , "Rafael J . Wysocki" , Shannon Zhao , Vladimir Zapolskiy , Len Brown Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 23, 2015 at 4:19 PM, Aleksey Makarov wrote: > From: Graeme Gregory > > On ARM64 some devices use the AMBA device and not the platform bus for > probing so add support for this. Uses a dummy clock for apb_pclk as ACPI > does not have a suitable clock representation and to keep the core > AMBA bus code unchanged between probing methods. > > Signed-off-by: Graeme Gregory > Signed-off-by: Aleksey Makarov > --- > drivers/acpi/Makefile | 1 + > drivers/acpi/acpi_amba.c | 140 +++++++++++++++++++++++++++++++++++++++++++++++ > drivers/acpi/internal.h | 5 ++ > 3 files changed, 146 insertions(+) > create mode 100644 drivers/acpi/acpi_amba.c > > diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile > index 675eaf3..3cf732f 100644 > --- a/drivers/acpi/Makefile > +++ b/drivers/acpi/Makefile > @@ -43,6 +43,7 @@ acpi-y += pci_root.o pci_link.o pci_irq.o > acpi-y += acpi_lpss.o acpi_apd.o > acpi-y += acpi_platform.o > acpi-y += acpi_pnp.o > +acpi-$(CONFIG_ARM_AMBA) += acpi_amba.o > acpi-y += int340x_thermal.o > acpi-y += power.o > acpi-y += event.o > diff --git a/drivers/acpi/acpi_amba.c b/drivers/acpi/acpi_amba.c > new file mode 100644 > index 0000000..4b77d47 > --- /dev/null > +++ b/drivers/acpi/acpi_amba.c > @@ -0,0 +1,140 @@ > + > +/* > + * ACPI support for platform bus type. > + * > + * Copyright (C) 2015, Linaro Ltd > + * Authors: Graeme Gregory Plural form implies more then one author which makes sense after what you did to the code. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include "internal.h" > + > +static const struct acpi_device_id amba_id_list[] = { > + {"ARMH0011", 0}, /* PL011 SBSA Uart */ > + {"ARMH0061", 0}, /* PL061 GPIO Device */ > + {"", 0}, > +}; > + > +static struct clk *amba_dummy_clk; You may move this into the function, it will be still global, but hidden from the namespace. > + > +static void amba_register_dummy_clk(void) > +{ > + struct clk *clk; > + > + /* If clock already registered */ > + if (amba_dummy_clk) > + return; > + > + clk = clk_register_fixed_rate(NULL, "apb_pclk", NULL, CLK_IS_ROOT, 0); > + clk_register_clkdev(clk, "apb_pclk", NULL); > + > + amba_dummy_clk = clk; > +} > + > +static int amba_handler_attach(struct acpi_device *adev, > + const struct acpi_device_id *id) > +{ > + struct amba_device *dev = NULL; Redundant assignment. > + struct acpi_device *acpi_parent; > + struct resource_entry *rentry; > + struct list_head resource_list; > + bool address_found = false; > + int ret, irq_no = 0; Better to split, they are not about the same by meaning. > + > + /* If the ACPI node already has a physical device attached, skip it. */ > + if (adev->physical_node_count) > + return 0; > + > + dev = amba_device_alloc(NULL, 0, 0); > + if (!dev) { > + dev_err(&adev->dev, "%s(): amba_device_alloc() failed\n", > + __func__); > + return -ENOMEM; > + } > + > + INIT_LIST_HEAD(&resource_list); > + ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); > + if (ret < 0) > + goto err_free; > + > + list_for_each_entry(rentry, &resource_list, node) { > + switch (resource_type(rentry->res)) { > + case IORESOURCE_MEM: > + if (!address_found) { > + dev->res = *rentry->res; > + address_found = true; > + } > + break; > + case IORESOURCE_IRQ: > + if (irq_no < AMBA_NR_IRQS) > + dev->irq[irq_no++] = rentry->res->start; > + break; > + default: > + dev_warn(&adev->dev, "Invalid resource\n"); Better to use break here as well. > + } > + } > + > + acpi_dev_free_resource_list(&resource_list); > + > + /* > + * If the ACPI node has a parent and that parent has a physical device > + * attached to it, that physical device should be the parent of the > + * platform device we are about to create. > + */ > + dev->dev.parent = NULL; > + acpi_parent = adev->parent; > + if (acpi_parent) { > + struct acpi_device_physical_node *entry; > + struct list_head *list; > + > + mutex_lock(&acpi_parent->physical_node_lock); > + list = &acpi_parent->physical_node_list; > + if (!list_empty(list)) { > + entry = list_first_entry(list, > + struct acpi_device_physical_node, > + node); There are couple of users already of the similar. I would suggest for now to create local helper which we might easily to move to one of drivers/acpi/ header. static inline struct acpi_device_physical_node *to_physical_node(struct acpi_dev *adev) { if (list_empty(adev->physical_node_list)) return NULL; return list_first_entry(adev->physical_node_list, struct acpi_device_physical_node, node); } Rafael, what do you think? > + dev->dev.parent = entry->dev; > + } > + mutex_unlock(&acpi_parent->physical_node_lock); > + } > + > + dev_set_name(&dev->dev, "%s", dev_name(&adev->dev)); > + ACPI_COMPANION_SET(&dev->dev, adev); > + > + ret = amba_device_add(dev, &iomem_resource); > + if (ret) { > + dev_err(&adev->dev, "%s(): amba_device_add() failed (%d)\n", > + __func__, ret); > + goto err_free; > + } > + Might be worth to comment out what 1 means here. > + return 1; > + > +err_free: > + amba_device_put(dev); > + return ret; > +} > + > +static struct acpi_scan_handler amba_handler = { > + .ids = amba_id_list, > + .attach = amba_handler_attach, > +}; > + > +void __init acpi_amba_init(void) > +{ > + amba_register_dummy_clk(); > + acpi_scan_add_handler(&amba_handler); > +} > diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h > index 11d87bf..9d58f0c 100644 > --- a/drivers/acpi/internal.h > +++ b/drivers/acpi/internal.h > @@ -29,6 +29,11 @@ void acpi_processor_init(void); > void acpi_platform_init(void); > void acpi_pnp_init(void); > void acpi_int340x_thermal_init(void); Hmm… Looks like we need specific header where drivers can put their stuff and share with other internal ACPI modules. > +#ifdef CONFIG_ARM_AMBA > +void acpi_amba_init(void); > +#else > +static inline void acpi_amba_init(void) {} > +#endif Same. > int acpi_sysfs_init(void); > void acpi_container_init(void); > void acpi_memory_hotplug_init(void); > -- > 2.6.4 > -- With Best Regards, Andy Shevchenko