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.
Cc: Rafael J. Wysocki <[email protected]> Cc: Len Brown <[email protected]> Cc: Russell King <[email protected]> Signed-off-by: Graeme Gregory <[email protected]> --- drivers/acpi/Makefile | 1 + drivers/acpi/acpi_amba.c | 157 +++++++++++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 1 + 3 files changed, 159 insertions(+) create mode 100644 drivers/acpi/acpi_amba.c diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index b5e7cd8..b94aa9f 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-y += 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..2f45b71 --- /dev/null +++ b/drivers/acpi/acpi_amba.c @@ -0,0 +1,157 @@ + +/* + * ACPI support for platform bus type. + * + * Copyright (C) 2015, Linaro Ltd + * Authors: Graeme Gregory <[email protected]> + * + * 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 <linux/acpi.h> +#include <linux/amba/bus.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/ioport.h> +#include <linux/kernel.h> +#include <linux/module.h> + +#ifdef CONFIG_ARM_AMBA +static const struct acpi_device_id amba_id_list[] = { + {"ARMH0011", 0}, /* PL011 SBSA Uart */ + {"ARMH0061", 0}, /* PL061 GPIO Device */ + {"", 0}, +}; + +struct clk *amba_dummy_clk; + +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; +} + +/** + * acpi_create_amba_device - Create platform device for ACPI device node + * @adev: ACPI device node to create a AMBA device for. + * + * Create and register an AMBA device, populate its common + * resources and return a pointer to it. Otherwise, return %NULL. + * + * Name of the AMBA device will be the same as @adev's. + */ +struct amba_device *acpi_create_amba_device(struct acpi_device *adev) +{ + 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 NULL; + + /* AMBA devices use amba_device not platform device */ + if (acpi_match_device_ids(adev, amba_id_list)) + return NULL; + + amba_register_dummy_clk(); + + 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 NULL; + } + + INIT_LIST_HEAD(&resource_list); + count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); + if (count < 0) { + return NULL; + } else if (count > 0) { + resources = kmalloc_array(count, sizeof(struct resource), + GFP_KERNEL); + if (!resources) { + acpi_dev_free_resource_list(&resource_list); + return ERR_PTR(-ENOMEM); + } + 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 dev; + +err_free: + amba_device_put(dev); + return NULL; +} +#else +struct amba_device *acpi_create_amba_device(struct acpi_device *adev) +{ + return NULL; +} +#endif /* CONFIG_ARM_AMBA */ +EXPORT_SYMBOL_GPL(acpi_create_amba_device); diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 84e7055..dc42ec0 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -457,6 +457,7 @@ int acpi_device_modalias(struct device *, char *, int); void acpi_walk_dep_device_list(acpi_handle handle); struct platform_device *acpi_create_platform_device(struct acpi_device *); +struct amba_device *acpi_create_amba_device(struct acpi_device *); #define ACPI_PTR(_ptr) (_ptr) #else /* !CONFIG_ACPI */ -- 2.4.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
