diff options
author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-04-27 23:53:41 (GMT) |
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committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2013-04-27 23:53:41 (GMT) |
commit | 2467d7b7037438f2d1fed826fc5217dddf4b37fb (patch) | |
tree | df18dcc4a4cc4c6cad3b79c3079a6791ceaae14a /drivers/acpi | |
parent | 929c6dd4195f6b4daf9887da34b3d7fbd0f2e2f5 (diff) | |
parent | cf8df962aa830d05be1a8d5a9c7d2a67b2837b45 (diff) | |
download | linux-2467d7b7037438f2d1fed826fc5217dddf4b37fb.tar.xz |
Merge branch 'acpi-lpss'
* acpi-lpss:
ACPI / LPSS: make code less confusing for reader
ACPI / LPSS: Add support for exposing LTR registers to user space
ACPI / scan: Add special handler for Intel Lynxpoint LPSS devices
Diffstat (limited to 'drivers/acpi')
-rw-r--r-- | drivers/acpi/Makefile | 1 | ||||
-rw-r--r-- | drivers/acpi/acpi_lpss.c | 292 | ||||
-rw-r--r-- | drivers/acpi/acpi_platform.c | 40 | ||||
-rw-r--r-- | drivers/acpi/internal.h | 8 | ||||
-rw-r--r-- | drivers/acpi/scan.c | 1 |
5 files changed, 304 insertions, 38 deletions
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile index 474fcfe..ecb743b 100644 --- a/drivers/acpi/Makefile +++ b/drivers/acpi/Makefile @@ -39,6 +39,7 @@ acpi-y += ec.o acpi-$(CONFIG_ACPI_DOCK) += dock.o acpi-y += pci_root.o pci_link.o pci_irq.o acpi-y += csrt.o +acpi-$(CONFIG_X86_INTEL_LPSS) += acpi_lpss.o acpi-y += acpi_platform.o acpi-y += power.o acpi-y += event.o diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c new file mode 100644 index 0000000..b1c9542 --- /dev/null +++ b/drivers/acpi/acpi_lpss.c @@ -0,0 +1,292 @@ +/* + * ACPI support for Intel Lynxpoint LPSS. + * + * Copyright (C) 2013, Intel Corporation + * Authors: Mika Westerberg <mika.westerberg@linux.intel.com> + * Rafael J. Wysocki <rafael.j.wysocki@intel.com> + * + * 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/clk.h> +#include <linux/clkdev.h> +#include <linux/clk-provider.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/platform_data/clk-lpss.h> +#include <linux/pm_runtime.h> + +#include "internal.h" + +ACPI_MODULE_NAME("acpi_lpss"); + +#define LPSS_CLK_SIZE 0x04 +#define LPSS_LTR_SIZE 0x18 + +/* Offsets relative to LPSS_PRIVATE_OFFSET */ +#define LPSS_GENERAL 0x08 +#define LPSS_GENERAL_LTR_MODE_SW BIT(2) +#define LPSS_SW_LTR 0x10 +#define LPSS_AUTO_LTR 0x14 + +struct lpss_device_desc { + bool clk_required; + const char *clk_parent; + bool ltr_required; + unsigned int prv_offset; +}; + +struct lpss_private_data { + void __iomem *mmio_base; + resource_size_t mmio_size; + struct clk *clk; + const struct lpss_device_desc *dev_desc; +}; + +static struct lpss_device_desc lpt_dev_desc = { + .clk_required = true, + .clk_parent = "lpss_clk", + .prv_offset = 0x800, + .ltr_required = true, +}; + +static struct lpss_device_desc lpt_sdio_dev_desc = { + .prv_offset = 0x1000, + .ltr_required = true, +}; + +static const struct acpi_device_id acpi_lpss_device_ids[] = { + /* Lynxpoint LPSS devices */ + { "INT33C0", (unsigned long)&lpt_dev_desc }, + { "INT33C1", (unsigned long)&lpt_dev_desc }, + { "INT33C2", (unsigned long)&lpt_dev_desc }, + { "INT33C3", (unsigned long)&lpt_dev_desc }, + { "INT33C4", (unsigned long)&lpt_dev_desc }, + { "INT33C5", (unsigned long)&lpt_dev_desc }, + { "INT33C6", (unsigned long)&lpt_sdio_dev_desc }, + { "INT33C7", }, + + { } +}; + +static int is_memory(struct acpi_resource *res, void *not_used) +{ + struct resource r; + return !acpi_dev_resource_memory(res, &r); +} + +/* LPSS main clock device. */ +static struct platform_device *lpss_clk_dev; + +static inline void lpt_register_clock_device(void) +{ + lpss_clk_dev = platform_device_register_simple("clk-lpt", -1, NULL, 0); +} + +static int register_device_clock(struct acpi_device *adev, + struct lpss_private_data *pdata) +{ + const struct lpss_device_desc *dev_desc = pdata->dev_desc; + + if (!lpss_clk_dev) + lpt_register_clock_device(); + + if (!dev_desc->clk_parent || !pdata->mmio_base + || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE) + return -ENODATA; + + pdata->clk = clk_register_gate(NULL, dev_name(&adev->dev), + dev_desc->clk_parent, 0, + pdata->mmio_base + dev_desc->prv_offset, + 0, 0, NULL); + if (IS_ERR(pdata->clk)) + return PTR_ERR(pdata->clk); + + clk_register_clkdev(pdata->clk, NULL, dev_name(&adev->dev)); + return 0; +} + +static int acpi_lpss_create_device(struct acpi_device *adev, + const struct acpi_device_id *id) +{ + struct lpss_device_desc *dev_desc; + struct lpss_private_data *pdata; + struct resource_list_entry *rentry; + struct list_head resource_list; + int ret; + + dev_desc = (struct lpss_device_desc *)id->driver_data; + if (!dev_desc) + return acpi_create_platform_device(adev, id); + + pdata = kzalloc(sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + + INIT_LIST_HEAD(&resource_list); + ret = acpi_dev_get_resources(adev, &resource_list, is_memory, NULL); + if (ret < 0) + goto err_out; + + list_for_each_entry(rentry, &resource_list, node) + if (resource_type(&rentry->res) == IORESOURCE_MEM) { + pdata->mmio_size = resource_size(&rentry->res); + pdata->mmio_base = ioremap(rentry->res.start, + pdata->mmio_size); + pdata->dev_desc = dev_desc; + break; + } + + acpi_dev_free_resource_list(&resource_list); + + if (dev_desc->clk_required) { + ret = register_device_clock(adev, pdata); + if (ret) { + /* + * Skip the device, but don't terminate the namespace + * scan. + */ + kfree(pdata); + return 0; + } + } + + adev->driver_data = pdata; + ret = acpi_create_platform_device(adev, id); + if (ret > 0) + return ret; + + adev->driver_data = NULL; + + err_out: + kfree(pdata); + return ret; +} + +static int lpss_reg_read(struct device *dev, unsigned int reg, u32 *val) +{ + struct acpi_device *adev; + struct lpss_private_data *pdata; + unsigned long flags; + int ret; + + ret = acpi_bus_get_device(ACPI_HANDLE(dev), &adev); + if (WARN_ON(ret)) + return ret; + + spin_lock_irqsave(&dev->power.lock, flags); + if (pm_runtime_suspended(dev)) { + ret = -EAGAIN; + goto out; + } + pdata = acpi_driver_data(adev); + if (WARN_ON(!pdata || !pdata->mmio_base)) { + ret = -ENODEV; + goto out; + } + *val = readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg); + + out: + spin_unlock_irqrestore(&dev->power.lock, flags); + return ret; +} + +static ssize_t lpss_ltr_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + u32 ltr_value = 0; + unsigned int reg; + int ret; + + reg = strcmp(attr->attr.name, "auto_ltr") ? LPSS_SW_LTR : LPSS_AUTO_LTR; + ret = lpss_reg_read(dev, reg, <r_value); + if (ret) + return ret; + + return snprintf(buf, PAGE_SIZE, "%08x\n", ltr_value); +} + +static ssize_t lpss_ltr_mode_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + u32 ltr_mode = 0; + char *outstr; + int ret; + + ret = lpss_reg_read(dev, LPSS_GENERAL, <r_mode); + if (ret) + return ret; + + outstr = (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) ? "sw" : "auto"; + return sprintf(buf, "%s\n", outstr); +} + +static DEVICE_ATTR(auto_ltr, S_IRUSR, lpss_ltr_show, NULL); +static DEVICE_ATTR(sw_ltr, S_IRUSR, lpss_ltr_show, NULL); +static DEVICE_ATTR(ltr_mode, S_IRUSR, lpss_ltr_mode_show, NULL); + +static struct attribute *lpss_attrs[] = { + &dev_attr_auto_ltr.attr, + &dev_attr_sw_ltr.attr, + &dev_attr_ltr_mode.attr, + NULL, +}; + +static struct attribute_group lpss_attr_group = { + .attrs = lpss_attrs, + .name = "lpss_ltr", +}; + +static int acpi_lpss_platform_notify(struct notifier_block *nb, + unsigned long action, void *data) +{ + struct platform_device *pdev = to_platform_device(data); + struct lpss_private_data *pdata; + struct acpi_device *adev; + const struct acpi_device_id *id; + int ret = 0; + + id = acpi_match_device(acpi_lpss_device_ids, &pdev->dev); + if (!id || !id->driver_data) + return 0; + + if (acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev)) + return 0; + + pdata = acpi_driver_data(adev); + if (!pdata || !pdata->mmio_base || !pdata->dev_desc->ltr_required) + return 0; + + if (pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) { + dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n"); + return 0; + } + + if (action == BUS_NOTIFY_ADD_DEVICE) + ret = sysfs_create_group(&pdev->dev.kobj, &lpss_attr_group); + else if (action == BUS_NOTIFY_DEL_DEVICE) + sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group); + + return ret; +} + +static struct notifier_block acpi_lpss_nb = { + .notifier_call = acpi_lpss_platform_notify, +}; + +static struct acpi_scan_handler lpss_handler = { + .ids = acpi_lpss_device_ids, + .attach = acpi_lpss_create_device, +}; + +void __init acpi_lpss_init(void) +{ + if (!lpt_clk_init()) { + bus_register_notifier(&platform_bus_type, &acpi_lpss_nb); + acpi_scan_add_handler(&lpss_handler); + } +} diff --git a/drivers/acpi/acpi_platform.c b/drivers/acpi/acpi_platform.c index 26fce4b..fafec5d 100644 --- a/drivers/acpi/acpi_platform.c +++ b/drivers/acpi/acpi_platform.c @@ -22,9 +22,6 @@ ACPI_MODULE_NAME("platform"); -/* Flags for acpi_create_platform_device */ -#define ACPI_PLATFORM_CLK BIT(0) - /* * The following ACPI IDs are known to be suitable for representing as * platform devices. @@ -33,33 +30,9 @@ static const struct acpi_device_id acpi_platform_device_ids[] = { { "PNP0D40" }, - /* Haswell LPSS devices */ - { "INT33C0", ACPI_PLATFORM_CLK }, - { "INT33C1", ACPI_PLATFORM_CLK }, - { "INT33C2", ACPI_PLATFORM_CLK }, - { "INT33C3", ACPI_PLATFORM_CLK }, - { "INT33C4", ACPI_PLATFORM_CLK }, - { "INT33C5", ACPI_PLATFORM_CLK }, - { "INT33C6", ACPI_PLATFORM_CLK }, - { "INT33C7", ACPI_PLATFORM_CLK }, - { } }; -static int acpi_create_platform_clks(struct acpi_device *adev) -{ - static struct platform_device *pdev; - - /* Create Lynxpoint LPSS clocks */ - if (!pdev && !strncmp(acpi_device_hid(adev), "INT33C", 6)) { - pdev = platform_device_register_simple("clk-lpt", -1, NULL, 0); - if (IS_ERR(pdev)) - return PTR_ERR(pdev); - } - - return 0; -} - /** * acpi_create_platform_device - Create platform device for ACPI device node * @adev: ACPI device node to create a platform device for. @@ -71,10 +44,9 @@ static int acpi_create_platform_clks(struct acpi_device *adev) * * Name of the platform device will be the same as @adev's. */ -static int acpi_create_platform_device(struct acpi_device *adev, - const struct acpi_device_id *id) +int acpi_create_platform_device(struct acpi_device *adev, + const struct acpi_device_id *id) { - unsigned long flags = id->driver_data; struct platform_device *pdev = NULL; struct acpi_device *acpi_parent; struct platform_device_info pdevinfo; @@ -83,14 +55,6 @@ static int acpi_create_platform_device(struct acpi_device *adev, struct resource *resources; int count; - if (flags & ACPI_PLATFORM_CLK) { - int ret = acpi_create_platform_clks(adev); - if (ret) { - dev_err(&adev->dev, "failed to create clocks\n"); - return ret; - } - } - /* If the ACPI node already has a physical device attached, skip it. */ if (adev->physical_node_count) return 0; diff --git a/drivers/acpi/internal.h b/drivers/acpi/internal.h index 7f094ad..6f1afd9 100644 --- a/drivers/acpi/internal.h +++ b/drivers/acpi/internal.h @@ -59,6 +59,11 @@ int acpi_debugfs_init(void); #else static inline void acpi_debugfs_init(void) { return; } #endif +#ifdef CONFIG_X86_INTEL_LPSS +void acpi_lpss_init(void); +#else +static inline void acpi_lpss_init(void) {} +#endif /* -------------------------------------------------------------------------- Device Node Initialization / Removal @@ -142,4 +147,7 @@ static inline void suspend_nvs_restore(void) {} -------------------------------------------------------------------------- */ struct platform_device; +int acpi_create_platform_device(struct acpi_device *adev, + const struct acpi_device_id *id); + #endif /* _ACPI_INTERNAL_H_ */ diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 8cacc16..d7f3c8b 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -2041,6 +2041,7 @@ int __init acpi_scan_init(void) acpi_pci_root_init(); acpi_pci_link_init(); acpi_platform_init(); + acpi_lpss_init(); acpi_csrt_init(); acpi_container_init(); acpi_pci_slot_init(); |