| /* |
| * 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 *clkdev_name; |
| bool ltr_required; |
| unsigned int prv_offset; |
| }; |
| |
| static struct lpss_device_desc lpss_dma_desc = { |
| .clk_required = true, |
| .clkdev_name = "hclk", |
| }; |
| |
| 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, |
| .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[] = { |
| /* Generic LPSS devices */ |
| { "INTL9C60", (unsigned long)&lpss_dma_desc }, |
| |
| /* 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; |
| struct lpss_clk_data *clk_data; |
| |
| if (!lpss_clk_dev) |
| lpt_register_clock_device(); |
| |
| clk_data = platform_get_drvdata(lpss_clk_dev); |
| if (!clk_data) |
| return -ENODEV; |
| |
| if (dev_desc->clkdev_name) { |
| clk_register_clkdev(clk_data->clk, dev_desc->clkdev_name, |
| dev_name(&adev->dev)); |
| return 0; |
| } |
| |
| if (!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), |
| clk_data->name, 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); |
| break; |
| } |
| |
| acpi_dev_free_resource_list(&resource_list); |
| |
| pdata->dev_desc = dev_desc; |
| |
| if (dev_desc->clk_required) { |
| ret = register_device_clock(adev, pdata); |
| if (ret) { |
| /* Skip the device, but continue the namespace scan. */ |
| ret = 0; |
| goto err_out; |
| } |
| } |
| |
| /* |
| * This works around a known issue in ACPI tables where LPSS devices |
| * have _PS0 and _PS3 without _PSC (and no power resources), so |
| * acpi_bus_init_power() will assume that the BIOS has put them into D0. |
| */ |
| ret = acpi_device_fix_up_power(adev); |
| if (ret) { |
| /* Skip the device, but continue the namespace scan. */ |
| ret = 0; |
| goto err_out; |
| } |
| |
| 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); |
| } |
| } |