Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753066AbbLUXyx (ORCPT ); Mon, 21 Dec 2015 18:54:53 -0500 Received: from mleia.com ([178.79.152.223]:50696 "EHLO mail.mleia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751978AbbLUXyv (ORCPT ); Mon, 21 Dec 2015 18:54:51 -0500 Message-ID: <56789147.8070602@mleia.com> Date: Tue, 22 Dec 2015 01:54:47 +0200 From: Vladimir Zapolskiy User-Agent: Mozilla/5.0 (X11; Linux i686; rv:31.0) Gecko/20100101 Icedove/31.6.0 MIME-Version: 1.0 To: Aleksey Makarov , linux-acpi@vger.kernel.org CC: Russell King , Graeme Gregory , Greg Kroah-Hartman , "Rafael J . Wysocki" , linux-kernel@vger.kernel.org, Shannon Zhao , linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Len Brown Subject: Re: [PATCH v3 1/3] ACPI: amba bus probing support References: <1450716100-13688-1-git-send-email-aleksey.makarov@linaro.org> <1450716100-13688-2-git-send-email-aleksey.makarov@linaro.org> In-Reply-To: <1450716100-13688-2-git-send-email-aleksey.makarov@linaro.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-49551924 X-CRM114-CacheID: sfid-20151221_235502_871723_F94D13BB X-CRM114-Status: GOOD ( 44.27 ) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6707 Lines: 227 Hi, On 21.12.2015 18:41, 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 | 149 +++++++++++++++++++++++++++++++++++++++++++++++ > drivers/acpi/internal.h | 5 ++ > 3 files changed, 155 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..ebc8913 > --- /dev/null > +++ b/drivers/acpi/acpi_amba.c > @@ -0,0 +1,149 @@ > + > +/* > + * ACPI support for platform bus type. > + * > + * Copyright (C) 2015, Linaro Ltd > + * Authors: Graeme Gregory > + * > + * 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; > + > +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; > + struct acpi_device *acpi_parent; > + struct resource_entry *rentry; > + struct list_head resource_list; > + struct resource *resources = NULL; > + bool address_found = false; > + int ret, count, irq_no = 0; > + > + /* If the ACPI node already has a physical device attached, skip it. */ > + if (adev->physical_node_count) > + return 0; > + > + amba_register_dummy_clk(); Since it is a single time dummy clock registration, may be it is better to move it to acpi_amba_init() or somewhere else? I understand that "apb_pclk" is wanted, but I'm not sure that this driver should serve as a clock provider. > + dev = amba_device_alloc(NULL, 0, 0); > + if (!dev) { > + pr_err("%s(): amba_device_alloc() failed for %s\n", > + __func__, dev_name(&adev->dev)); > + return 0; > + } > + > + INIT_LIST_HEAD(&resource_list); > + count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); > + if (count < 0) { > + return 0; > + } else if (count > 0) { if you return from one of two if-branches, please don't use if-else nesting for another one. > + resources = kmalloc_array(count, sizeof(struct resource), > + GFP_KERNEL); resources is never used and it is never freed, why do you allocate it? > + if (!resources) { > + acpi_dev_free_resource_list(&resource_list); > + return 0; return -ENOMEM; seems to be more appropriate here. > + } > + count = 0; > + 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"); > + } > + } > + 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); > + 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) { > + pr_err("%s(): amba_device_add() failed (%d) for %s\n", > + __func__, ret, dev_name(&adev->dev)); > + goto err_free; > + } > + > + return 1; > + > +err_free: > + amba_device_put(dev); > + return 0; > +} > + > +static struct acpi_scan_handler amba_handler = { > + .ids = amba_id_list, > + .attach = amba_handler_attach, > +}; > + > +void __init acpi_amba_init(void) > +{ > + 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); > +#ifdef CONFIG_ARM_AMBA > +void acpi_amba_init(void); > +#else > +static inline void acpi_amba_init(void) {} > +#endif > int acpi_sysfs_init(void); > void acpi_container_init(void); > void acpi_memory_hotplug_init(void); > -- With best wishes, Vladimir -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/