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path: root/drivers/acpi/acpi_lpss.c
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Diffstat (limited to 'drivers/acpi/acpi_lpss.c')
-rw-r--r--drivers/acpi/acpi_lpss.c749
1 files changed, 749 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
new file mode 100644
index 000000000..73f056a59
--- /dev/null
+++ b/drivers/acpi/acpi_lpss.c
@@ -0,0 +1,749 @@
+/*
+ * 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 <linux/delay.h>
+
+#include "internal.h"
+
+ACPI_MODULE_NAME("acpi_lpss");
+
+#ifdef CONFIG_X86_INTEL_LPSS
+
+#define LPSS_ADDR(desc) ((unsigned long)&desc)
+
+#define LPSS_CLK_SIZE 0x04
+#define LPSS_LTR_SIZE 0x18
+
+/* Offsets relative to LPSS_PRIVATE_OFFSET */
+#define LPSS_CLK_DIVIDER_DEF_MASK (BIT(1) | BIT(16))
+#define LPSS_RESETS 0x04
+#define LPSS_RESETS_RESET_FUNC BIT(0)
+#define LPSS_RESETS_RESET_APB BIT(1)
+#define LPSS_GENERAL 0x08
+#define LPSS_GENERAL_LTR_MODE_SW BIT(2)
+#define LPSS_GENERAL_UART_RTS_OVRD BIT(3)
+#define LPSS_SW_LTR 0x10
+#define LPSS_AUTO_LTR 0x14
+#define LPSS_LTR_SNOOP_REQ BIT(15)
+#define LPSS_LTR_SNOOP_MASK 0x0000FFFF
+#define LPSS_LTR_SNOOP_LAT_1US 0x800
+#define LPSS_LTR_SNOOP_LAT_32US 0xC00
+#define LPSS_LTR_SNOOP_LAT_SHIFT 5
+#define LPSS_LTR_SNOOP_LAT_CUTOFF 3000
+#define LPSS_LTR_MAX_VAL 0x3FF
+#define LPSS_TX_INT 0x20
+#define LPSS_TX_INT_MASK BIT(1)
+
+#define LPSS_PRV_REG_COUNT 9
+
+/* LPSS Flags */
+#define LPSS_CLK BIT(0)
+#define LPSS_CLK_GATE BIT(1)
+#define LPSS_CLK_DIVIDER BIT(2)
+#define LPSS_LTR BIT(3)
+#define LPSS_SAVE_CTX BIT(4)
+
+struct lpss_private_data;
+
+struct lpss_device_desc {
+ unsigned int flags;
+ const char *clk_con_id;
+ unsigned int prv_offset;
+ size_t prv_size_override;
+ void (*setup)(struct lpss_private_data *pdata);
+};
+
+static struct lpss_device_desc lpss_dma_desc = {
+ .flags = LPSS_CLK,
+};
+
+struct lpss_private_data {
+ void __iomem *mmio_base;
+ resource_size_t mmio_size;
+ unsigned int fixed_clk_rate;
+ struct clk *clk;
+ const struct lpss_device_desc *dev_desc;
+ u32 prv_reg_ctx[LPSS_PRV_REG_COUNT];
+};
+
+/* UART Component Parameter Register */
+#define LPSS_UART_CPR 0xF4
+#define LPSS_UART_CPR_AFCE BIT(4)
+
+static void lpss_uart_setup(struct lpss_private_data *pdata)
+{
+ unsigned int offset;
+ u32 val;
+
+ offset = pdata->dev_desc->prv_offset + LPSS_TX_INT;
+ val = readl(pdata->mmio_base + offset);
+ writel(val | LPSS_TX_INT_MASK, pdata->mmio_base + offset);
+
+ val = readl(pdata->mmio_base + LPSS_UART_CPR);
+ if (!(val & LPSS_UART_CPR_AFCE)) {
+ offset = pdata->dev_desc->prv_offset + LPSS_GENERAL;
+ val = readl(pdata->mmio_base + offset);
+ val |= LPSS_GENERAL_UART_RTS_OVRD;
+ writel(val, pdata->mmio_base + offset);
+ }
+}
+
+static void lpss_deassert_reset(struct lpss_private_data *pdata)
+{
+ unsigned int offset;
+ u32 val;
+
+ offset = pdata->dev_desc->prv_offset + LPSS_RESETS;
+ val = readl(pdata->mmio_base + offset);
+ val |= LPSS_RESETS_RESET_APB | LPSS_RESETS_RESET_FUNC;
+ writel(val, pdata->mmio_base + offset);
+}
+
+#define LPSS_I2C_ENABLE 0x6c
+
+static void byt_i2c_setup(struct lpss_private_data *pdata)
+{
+ lpss_deassert_reset(pdata);
+
+ if (readl(pdata->mmio_base + pdata->dev_desc->prv_offset))
+ pdata->fixed_clk_rate = 133000000;
+
+ writel(0, pdata->mmio_base + LPSS_I2C_ENABLE);
+}
+
+static struct lpss_device_desc lpt_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
+ .prv_offset = 0x800,
+};
+
+static struct lpss_device_desc lpt_i2c_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
+ .prv_offset = 0x800,
+};
+
+static struct lpss_device_desc lpt_uart_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
+ .clk_con_id = "baudclk",
+ .prv_offset = 0x800,
+ .setup = lpss_uart_setup,
+};
+
+static struct lpss_device_desc lpt_sdio_dev_desc = {
+ .flags = LPSS_LTR,
+ .prv_offset = 0x1000,
+ .prv_size_override = 0x1018,
+};
+
+static struct lpss_device_desc byt_pwm_dev_desc = {
+ .flags = LPSS_SAVE_CTX,
+};
+
+static struct lpss_device_desc byt_uart_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
+ .clk_con_id = "baudclk",
+ .prv_offset = 0x800,
+ .setup = lpss_uart_setup,
+};
+
+static struct lpss_device_desc byt_spi_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
+ .prv_offset = 0x400,
+};
+
+static struct lpss_device_desc byt_sdio_dev_desc = {
+ .flags = LPSS_CLK,
+};
+
+static struct lpss_device_desc byt_i2c_dev_desc = {
+ .flags = LPSS_CLK | LPSS_SAVE_CTX,
+ .prv_offset = 0x800,
+ .setup = byt_i2c_setup,
+};
+
+static struct lpss_device_desc bsw_spi_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
+ .prv_offset = 0x400,
+ .setup = lpss_deassert_reset,
+};
+
+#else
+
+#define LPSS_ADDR(desc) (0UL)
+
+#endif /* CONFIG_X86_INTEL_LPSS */
+
+static const struct acpi_device_id acpi_lpss_device_ids[] = {
+ /* Generic LPSS devices */
+ { "INTL9C60", LPSS_ADDR(lpss_dma_desc) },
+
+ /* Lynxpoint LPSS devices */
+ { "INT33C0", LPSS_ADDR(lpt_dev_desc) },
+ { "INT33C1", LPSS_ADDR(lpt_dev_desc) },
+ { "INT33C2", LPSS_ADDR(lpt_i2c_dev_desc) },
+ { "INT33C3", LPSS_ADDR(lpt_i2c_dev_desc) },
+ { "INT33C4", LPSS_ADDR(lpt_uart_dev_desc) },
+ { "INT33C5", LPSS_ADDR(lpt_uart_dev_desc) },
+ { "INT33C6", LPSS_ADDR(lpt_sdio_dev_desc) },
+ { "INT33C7", },
+
+ /* BayTrail LPSS devices */
+ { "80860F09", LPSS_ADDR(byt_pwm_dev_desc) },
+ { "80860F0A", LPSS_ADDR(byt_uart_dev_desc) },
+ { "80860F0E", LPSS_ADDR(byt_spi_dev_desc) },
+ { "80860F14", LPSS_ADDR(byt_sdio_dev_desc) },
+ { "80860F41", LPSS_ADDR(byt_i2c_dev_desc) },
+ { "INT33B2", },
+ { "INT33FC", },
+
+ /* Braswell LPSS devices */
+ { "80862288", LPSS_ADDR(byt_pwm_dev_desc) },
+ { "8086228A", LPSS_ADDR(byt_uart_dev_desc) },
+ { "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
+ { "808622C1", LPSS_ADDR(byt_i2c_dev_desc) },
+
+ { "INT3430", LPSS_ADDR(lpt_dev_desc) },
+ { "INT3431", LPSS_ADDR(lpt_dev_desc) },
+ { "INT3432", LPSS_ADDR(lpt_i2c_dev_desc) },
+ { "INT3433", LPSS_ADDR(lpt_i2c_dev_desc) },
+ { "INT3434", LPSS_ADDR(lpt_uart_dev_desc) },
+ { "INT3435", LPSS_ADDR(lpt_uart_dev_desc) },
+ { "INT3436", LPSS_ADDR(lpt_sdio_dev_desc) },
+ { "INT3437", },
+
+ /* Wildcat Point LPSS devices */
+ { "INT3438", LPSS_ADDR(lpt_dev_desc) },
+
+ { }
+};
+
+#ifdef CONFIG_X86_INTEL_LPSS
+
+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;
+ const char *devname = dev_name(&adev->dev);
+ struct clk *clk = ERR_PTR(-ENODEV);
+ struct lpss_clk_data *clk_data;
+ const char *parent, *clk_name;
+ void __iomem *prv_base;
+
+ if (!lpss_clk_dev)
+ lpt_register_clock_device();
+
+ clk_data = platform_get_drvdata(lpss_clk_dev);
+ if (!clk_data)
+ return -ENODEV;
+ clk = clk_data->clk;
+
+ if (!pdata->mmio_base
+ || pdata->mmio_size < dev_desc->prv_offset + LPSS_CLK_SIZE)
+ return -ENODATA;
+
+ parent = clk_data->name;
+ prv_base = pdata->mmio_base + dev_desc->prv_offset;
+
+ if (pdata->fixed_clk_rate) {
+ clk = clk_register_fixed_rate(NULL, devname, parent, 0,
+ pdata->fixed_clk_rate);
+ goto out;
+ }
+
+ if (dev_desc->flags & LPSS_CLK_GATE) {
+ clk = clk_register_gate(NULL, devname, parent, 0,
+ prv_base, 0, 0, NULL);
+ parent = devname;
+ }
+
+ if (dev_desc->flags & LPSS_CLK_DIVIDER) {
+ /* Prevent division by zero */
+ if (!readl(prv_base))
+ writel(LPSS_CLK_DIVIDER_DEF_MASK, prv_base);
+
+ clk_name = kasprintf(GFP_KERNEL, "%s-div", devname);
+ if (!clk_name)
+ return -ENOMEM;
+ clk = clk_register_fractional_divider(NULL, clk_name, parent,
+ 0, prv_base,
+ 1, 15, 16, 15, 0, NULL);
+ parent = clk_name;
+
+ clk_name = kasprintf(GFP_KERNEL, "%s-update", devname);
+ if (!clk_name) {
+ kfree(parent);
+ return -ENOMEM;
+ }
+ clk = clk_register_gate(NULL, clk_name, parent,
+ CLK_SET_RATE_PARENT | CLK_SET_RATE_GATE,
+ prv_base, 31, 0, NULL);
+ kfree(parent);
+ kfree(clk_name);
+ }
+out:
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ pdata->clk = clk;
+ clk_register_clkdev(clk, dev_desc->clk_con_id, devname);
+ 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_entry *rentry;
+ struct list_head resource_list;
+ struct platform_device *pdev;
+ int ret;
+
+ dev_desc = (struct lpss_device_desc *)id->driver_data;
+ if (!dev_desc) {
+ pdev = acpi_create_platform_device(adev);
+ return IS_ERR_OR_NULL(pdev) ? PTR_ERR(pdev) : 1;
+ }
+ 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) {
+ if (dev_desc->prv_size_override)
+ pdata->mmio_size = dev_desc->prv_size_override;
+ else
+ 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);
+
+ if (!pdata->mmio_base) {
+ ret = -ENOMEM;
+ goto err_out;
+ }
+
+ pdata->dev_desc = dev_desc;
+
+ if (dev_desc->setup)
+ dev_desc->setup(pdata);
+
+ if (dev_desc->flags & LPSS_CLK) {
+ 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;
+ pdev = acpi_create_platform_device(adev);
+ if (!IS_ERR_OR_NULL(pdev)) {
+ return 1;
+ }
+
+ ret = PTR_ERR(pdev);
+ adev->driver_data = NULL;
+
+ err_out:
+ kfree(pdata);
+ return ret;
+}
+
+static u32 __lpss_reg_read(struct lpss_private_data *pdata, unsigned int reg)
+{
+ return readl(pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
+}
+
+static void __lpss_reg_write(u32 val, struct lpss_private_data *pdata,
+ unsigned int reg)
+{
+ writel(val, pdata->mmio_base + pdata->dev_desc->prv_offset + reg);
+}
+
+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 = __lpss_reg_read(pdata, 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, &ltr_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, &ltr_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 void acpi_lpss_set_ltr(struct device *dev, s32 val)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ u32 ltr_mode, ltr_val;
+
+ ltr_mode = __lpss_reg_read(pdata, LPSS_GENERAL);
+ if (val < 0) {
+ if (ltr_mode & LPSS_GENERAL_LTR_MODE_SW) {
+ ltr_mode &= ~LPSS_GENERAL_LTR_MODE_SW;
+ __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
+ }
+ return;
+ }
+ ltr_val = __lpss_reg_read(pdata, LPSS_SW_LTR) & ~LPSS_LTR_SNOOP_MASK;
+ if (val >= LPSS_LTR_SNOOP_LAT_CUTOFF) {
+ ltr_val |= LPSS_LTR_SNOOP_LAT_32US;
+ val = LPSS_LTR_MAX_VAL;
+ } else if (val > LPSS_LTR_MAX_VAL) {
+ ltr_val |= LPSS_LTR_SNOOP_LAT_32US | LPSS_LTR_SNOOP_REQ;
+ val >>= LPSS_LTR_SNOOP_LAT_SHIFT;
+ } else {
+ ltr_val |= LPSS_LTR_SNOOP_LAT_1US | LPSS_LTR_SNOOP_REQ;
+ }
+ ltr_val |= val;
+ __lpss_reg_write(ltr_val, pdata, LPSS_SW_LTR);
+ if (!(ltr_mode & LPSS_GENERAL_LTR_MODE_SW)) {
+ ltr_mode |= LPSS_GENERAL_LTR_MODE_SW;
+ __lpss_reg_write(ltr_mode, pdata, LPSS_GENERAL);
+ }
+}
+
+#ifdef CONFIG_PM
+/**
+ * acpi_lpss_save_ctx() - Save the private registers of LPSS device
+ * @dev: LPSS device
+ * @pdata: pointer to the private data of the LPSS device
+ *
+ * Most LPSS devices have private registers which may loose their context when
+ * the device is powered down. acpi_lpss_save_ctx() saves those registers into
+ * prv_reg_ctx array.
+ */
+static void acpi_lpss_save_ctx(struct device *dev,
+ struct lpss_private_data *pdata)
+{
+ unsigned int i;
+
+ for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
+ unsigned long offset = i * sizeof(u32);
+
+ pdata->prv_reg_ctx[i] = __lpss_reg_read(pdata, offset);
+ dev_dbg(dev, "saving 0x%08x from LPSS reg at offset 0x%02lx\n",
+ pdata->prv_reg_ctx[i], offset);
+ }
+}
+
+/**
+ * acpi_lpss_restore_ctx() - Restore the private registers of LPSS device
+ * @dev: LPSS device
+ * @pdata: pointer to the private data of the LPSS device
+ *
+ * Restores the registers that were previously stored with acpi_lpss_save_ctx().
+ */
+static void acpi_lpss_restore_ctx(struct device *dev,
+ struct lpss_private_data *pdata)
+{
+ unsigned int i;
+
+ /*
+ * The following delay is needed or the subsequent write operations may
+ * fail. The LPSS devices are actually PCI devices and the PCI spec
+ * expects 10ms delay before the device can be accessed after D3 to D0
+ * transition.
+ */
+ msleep(10);
+
+ for (i = 0; i < LPSS_PRV_REG_COUNT; i++) {
+ unsigned long offset = i * sizeof(u32);
+
+ __lpss_reg_write(pdata->prv_reg_ctx[i], pdata, offset);
+ dev_dbg(dev, "restoring 0x%08x to LPSS reg at offset 0x%02lx\n",
+ pdata->prv_reg_ctx[i], offset);
+ }
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int acpi_lpss_suspend_late(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = pm_generic_suspend_late(dev);
+ if (ret)
+ return ret;
+
+ if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+ acpi_lpss_save_ctx(dev, pdata);
+
+ return acpi_dev_suspend_late(dev);
+}
+
+static int acpi_lpss_resume_early(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = acpi_dev_resume_early(dev);
+ if (ret)
+ return ret;
+
+ if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+ acpi_lpss_restore_ctx(dev, pdata);
+
+ return pm_generic_resume_early(dev);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static int acpi_lpss_runtime_suspend(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = pm_generic_runtime_suspend(dev);
+ if (ret)
+ return ret;
+
+ if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+ acpi_lpss_save_ctx(dev, pdata);
+
+ return acpi_dev_runtime_suspend(dev);
+}
+
+static int acpi_lpss_runtime_resume(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = acpi_dev_runtime_resume(dev);
+ if (ret)
+ return ret;
+
+ if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+ acpi_lpss_restore_ctx(dev, pdata);
+
+ return pm_generic_runtime_resume(dev);
+}
+#endif /* CONFIG_PM */
+
+static struct dev_pm_domain acpi_lpss_pm_domain = {
+ .ops = {
+#ifdef CONFIG_PM
+#ifdef CONFIG_PM_SLEEP
+ .prepare = acpi_subsys_prepare,
+ .complete = acpi_subsys_complete,
+ .suspend = acpi_subsys_suspend,
+ .suspend_late = acpi_lpss_suspend_late,
+ .resume_early = acpi_lpss_resume_early,
+ .freeze = acpi_subsys_freeze,
+ .poweroff = acpi_subsys_suspend,
+ .poweroff_late = acpi_lpss_suspend_late,
+ .restore_early = acpi_lpss_resume_early,
+#endif
+ .runtime_suspend = acpi_lpss_runtime_suspend,
+ .runtime_resume = acpi_lpss_runtime_resume,
+#endif
+ },
+};
+
+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;
+
+ 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)
+ return 0;
+
+ if (pdata->mmio_base &&
+ pdata->mmio_size < pdata->dev_desc->prv_offset + LPSS_LTR_SIZE) {
+ dev_err(&pdev->dev, "MMIO size insufficient to access LTR\n");
+ return 0;
+ }
+
+ switch (action) {
+ case BUS_NOTIFY_ADD_DEVICE:
+ pdev->dev.pm_domain = &acpi_lpss_pm_domain;
+ if (pdata->dev_desc->flags & LPSS_LTR)
+ return sysfs_create_group(&pdev->dev.kobj,
+ &lpss_attr_group);
+ break;
+ case BUS_NOTIFY_DEL_DEVICE:
+ if (pdata->dev_desc->flags & LPSS_LTR)
+ sysfs_remove_group(&pdev->dev.kobj, &lpss_attr_group);
+ pdev->dev.pm_domain = NULL;
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+static struct notifier_block acpi_lpss_nb = {
+ .notifier_call = acpi_lpss_platform_notify,
+};
+
+static void acpi_lpss_bind(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (!pdata || !pdata->mmio_base || !(pdata->dev_desc->flags & LPSS_LTR))
+ return;
+
+ if (pdata->mmio_size >= pdata->dev_desc->prv_offset + LPSS_LTR_SIZE)
+ dev->power.set_latency_tolerance = acpi_lpss_set_ltr;
+ else
+ dev_err(dev, "MMIO size insufficient to access LTR\n");
+}
+
+static void acpi_lpss_unbind(struct device *dev)
+{
+ dev->power.set_latency_tolerance = NULL;
+}
+
+static struct acpi_scan_handler lpss_handler = {
+ .ids = acpi_lpss_device_ids,
+ .attach = acpi_lpss_create_device,
+ .bind = acpi_lpss_bind,
+ .unbind = acpi_lpss_unbind,
+};
+
+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);
+ }
+}
+
+#else
+
+static struct acpi_scan_handler lpss_handler = {
+ .ids = acpi_lpss_device_ids,
+};
+
+void __init acpi_lpss_init(void)
+{
+ acpi_scan_add_handler(&lpss_handler);
+}
+
+#endif /* CONFIG_X86_INTEL_LPSS */