summaryrefslogtreecommitdiffstats
path: root/drivers/acpi/acpi_lpss.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/acpi/acpi_lpss.c')
-rw-r--r--drivers/acpi/acpi_lpss.c1365
1 files changed, 1365 insertions, 0 deletions
diff --git a/drivers/acpi/acpi_lpss.c b/drivers/acpi/acpi_lpss.c
new file mode 100644
index 000000000..6ff81027c
--- /dev/null
+++ b/drivers/acpi/acpi_lpss.c
@@ -0,0 +1,1365 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ */
+
+#include <linux/acpi.h>
+#include <linux/clkdev.h>
+#include <linux/clk-provider.h>
+#include <linux/dmi.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/mutex.h>
+#include <linux/pci.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/x86/clk-lpss.h>
+#include <linux/platform_data/x86/pmc_atom.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/pwm.h>
+#include <linux/suspend.h>
+#include <linux/delay.h>
+
+#include "internal.h"
+
+#ifdef CONFIG_X86_INTEL_LPSS
+
+#include <asm/cpu_device_id.h>
+#include <asm/intel-family.h>
+#include <asm/iosf_mbi.h>
+
+#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)
+/*
+ * For some devices the DSDT AML code for another device turns off the device
+ * before our suspend handler runs, causing us to read/save all 1-s (0xffffffff)
+ * as ctx register values.
+ * Luckily these devices always use the same ctx register values, so we can
+ * work around this by saving the ctx registers once on activation.
+ */
+#define LPSS_SAVE_CTX_ONCE BIT(5)
+#define LPSS_NO_D3_DELAY BIT(6)
+
+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;
+ struct property_entry *properties;
+ void (*setup)(struct lpss_private_data *pdata);
+ bool resume_from_noirq;
+};
+
+static const struct lpss_device_desc lpss_dma_desc = {
+ .flags = LPSS_CLK,
+};
+
+struct lpss_private_data {
+ struct acpi_device *adev;
+ 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];
+};
+
+/* Devices which need to be in D3 before lpss_iosf_enter_d3_state() proceeds */
+static u32 pmc_atom_d3_mask = 0xfe000ffe;
+
+/* LPSS run time quirks */
+static unsigned int lpss_quirks;
+
+/*
+ * LPSS_QUIRK_ALWAYS_POWER_ON: override power state for LPSS DMA device.
+ *
+ * The LPSS DMA controller has neither _PS0 nor _PS3 method. Moreover
+ * it can be powered off automatically whenever the last LPSS device goes down.
+ * In case of no power any access to the DMA controller will hang the system.
+ * The behaviour is reproduced on some HP laptops based on Intel BayTrail as
+ * well as on ASuS T100TA transformer.
+ *
+ * This quirk overrides power state of entire LPSS island to keep DMA powered
+ * on whenever we have at least one other device in use.
+ */
+#define LPSS_QUIRK_ALWAYS_POWER_ON BIT(0)
+
+/* 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);
+}
+
+/*
+ * BYT PWM used for backlight control by the i915 driver on systems without
+ * the Crystal Cove PMIC.
+ */
+static struct pwm_lookup byt_pwm_lookup[] = {
+ PWM_LOOKUP_WITH_MODULE("80860F09:00", 0, "0000:00:02.0",
+ "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
+ "pwm-lpss-platform"),
+};
+
+static void byt_pwm_setup(struct lpss_private_data *pdata)
+{
+ struct acpi_device *adev = pdata->adev;
+
+ /* Only call pwm_add_table for the first PWM controller */
+ if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
+ return;
+
+ pwm_add_table(byt_pwm_lookup, ARRAY_SIZE(byt_pwm_lookup));
+}
+
+#define LPSS_I2C_ENABLE 0x6c
+
+static void byt_i2c_setup(struct lpss_private_data *pdata)
+{
+ const char *uid_str = acpi_device_uid(pdata->adev);
+ acpi_handle handle = pdata->adev->handle;
+ unsigned long long shared_host = 0;
+ acpi_status status;
+ long uid = 0;
+
+ /* Expected to always be true, but better safe then sorry */
+ if (uid_str)
+ uid = simple_strtol(uid_str, NULL, 10);
+
+ /* Detect I2C bus shared with PUNIT and ignore its d3 status */
+ status = acpi_evaluate_integer(handle, "_SEM", NULL, &shared_host);
+ if (ACPI_SUCCESS(status) && shared_host && uid)
+ pmc_atom_d3_mask &= ~(BIT_LPSS2_F1_I2C1 << (uid - 1));
+
+ 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);
+}
+
+/* BSW PWM used for backlight control by the i915 driver */
+static struct pwm_lookup bsw_pwm_lookup[] = {
+ PWM_LOOKUP_WITH_MODULE("80862288:00", 0, "0000:00:02.0",
+ "pwm_soc_backlight", 0, PWM_POLARITY_NORMAL,
+ "pwm-lpss-platform"),
+};
+
+static void bsw_pwm_setup(struct lpss_private_data *pdata)
+{
+ struct acpi_device *adev = pdata->adev;
+
+ /* Only call pwm_add_table for the first PWM controller */
+ if (!adev->pnp.unique_id || strcmp(adev->pnp.unique_id, "1"))
+ return;
+
+ pwm_add_table(bsw_pwm_lookup, ARRAY_SIZE(bsw_pwm_lookup));
+}
+
+static const struct lpss_device_desc lpt_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
+ | LPSS_SAVE_CTX,
+ .prv_offset = 0x800,
+};
+
+static const struct lpss_device_desc lpt_i2c_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR | LPSS_SAVE_CTX,
+ .prv_offset = 0x800,
+};
+
+static struct property_entry uart_properties[] = {
+ PROPERTY_ENTRY_U32("reg-io-width", 4),
+ PROPERTY_ENTRY_U32("reg-shift", 2),
+ PROPERTY_ENTRY_BOOL("snps,uart-16550-compatible"),
+ { },
+};
+
+static const struct lpss_device_desc lpt_uart_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR
+ | LPSS_SAVE_CTX,
+ .clk_con_id = "baudclk",
+ .prv_offset = 0x800,
+ .setup = lpss_uart_setup,
+ .properties = uart_properties,
+};
+
+static const struct lpss_device_desc lpt_sdio_dev_desc = {
+ .flags = LPSS_LTR,
+ .prv_offset = 0x1000,
+ .prv_size_override = 0x1018,
+};
+
+static const struct lpss_device_desc byt_pwm_dev_desc = {
+ .flags = LPSS_SAVE_CTX,
+ .prv_offset = 0x800,
+ .setup = byt_pwm_setup,
+};
+
+static const struct lpss_device_desc bsw_pwm_dev_desc = {
+ .flags = LPSS_SAVE_CTX_ONCE | LPSS_NO_D3_DELAY,
+ .prv_offset = 0x800,
+ .setup = bsw_pwm_setup,
+ .resume_from_noirq = true,
+};
+
+static const 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,
+ .properties = uart_properties,
+};
+
+static const struct lpss_device_desc bsw_uart_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
+ | LPSS_NO_D3_DELAY,
+ .clk_con_id = "baudclk",
+ .prv_offset = 0x800,
+ .setup = lpss_uart_setup,
+ .properties = uart_properties,
+};
+
+static const struct lpss_device_desc byt_spi_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX,
+ .prv_offset = 0x400,
+};
+
+static const struct lpss_device_desc byt_sdio_dev_desc = {
+ .flags = LPSS_CLK,
+};
+
+static const struct lpss_device_desc byt_i2c_dev_desc = {
+ .flags = LPSS_CLK | LPSS_SAVE_CTX,
+ .prv_offset = 0x800,
+ .setup = byt_i2c_setup,
+ .resume_from_noirq = true,
+};
+
+static const struct lpss_device_desc bsw_i2c_dev_desc = {
+ .flags = LPSS_CLK | LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
+ .prv_offset = 0x800,
+ .setup = byt_i2c_setup,
+ .resume_from_noirq = true,
+};
+
+static const struct lpss_device_desc bsw_spi_dev_desc = {
+ .flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_SAVE_CTX
+ | LPSS_NO_D3_DELAY,
+ .prv_offset = 0x400,
+ .setup = lpss_deassert_reset,
+};
+
+static const struct x86_cpu_id lpss_cpu_ids[] = {
+ X86_MATCH_INTEL_FAM6_MODEL(ATOM_SILVERMONT, NULL),
+ X86_MATCH_INTEL_FAM6_MODEL(ATOM_AIRMONT, NULL),
+ {}
+};
+
+#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 */
+ { "80862286", LPSS_ADDR(lpss_dma_desc) },
+ { "80862288", LPSS_ADDR(bsw_pwm_dev_desc) },
+ { "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
+ { "8086228E", LPSS_ADDR(bsw_spi_dev_desc) },
+ { "808622C0", LPSS_ADDR(lpss_dma_desc) },
+ { "808622C1", LPSS_ADDR(bsw_i2c_dev_desc) },
+
+ /* Broadwell LPSS devices */
+ { "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;
+ struct lpss_clk_data *clk_data;
+ const char *parent, *clk_name;
+ void __iomem *prv_base;
+
+ if (!lpss_clk_dev)
+ lpt_register_clock_device();
+
+ if (IS_ERR(lpss_clk_dev))
+ return PTR_ERR(lpss_clk_dev);
+
+ 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;
+}
+
+struct lpss_device_links {
+ const char *supplier_hid;
+ const char *supplier_uid;
+ const char *consumer_hid;
+ const char *consumer_uid;
+ u32 flags;
+ const struct dmi_system_id *dep_missing_ids;
+};
+
+/* Please keep this list sorted alphabetically by vendor and model */
+static const struct dmi_system_id i2c1_dep_missing_dmi_ids[] = {
+ {
+ .matches = {
+ DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
+ DMI_MATCH(DMI_PRODUCT_NAME, "T200TA"),
+ },
+ },
+ {}
+};
+
+/*
+ * The _DEP method is used to identify dependencies but instead of creating
+ * device links for every handle in _DEP, only links in the following list are
+ * created. That is necessary because, in the general case, _DEP can refer to
+ * devices that might not have drivers, or that are on different buses, or where
+ * the supplier is not enumerated until after the consumer is probed.
+ */
+static const struct lpss_device_links lpss_device_links[] = {
+ /* CHT External sdcard slot controller depends on PMIC I2C ctrl */
+ {"808622C1", "7", "80860F14", "3", DL_FLAG_PM_RUNTIME},
+ /* CHT iGPU depends on PMIC I2C controller */
+ {"808622C1", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
+ /* BYT iGPU depends on the Embedded Controller I2C controller (UID 1) */
+ {"80860F41", "1", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME,
+ i2c1_dep_missing_dmi_ids},
+ /* BYT CR iGPU depends on PMIC I2C controller (UID 5 on CR) */
+ {"80860F41", "5", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
+ /* BYT iGPU depends on PMIC I2C controller (UID 7 on non CR) */
+ {"80860F41", "7", "LNXVIDEO", NULL, DL_FLAG_PM_RUNTIME},
+};
+
+static bool acpi_lpss_is_supplier(struct acpi_device *adev,
+ const struct lpss_device_links *link)
+{
+ return acpi_dev_hid_uid_match(adev, link->supplier_hid, link->supplier_uid);
+}
+
+static bool acpi_lpss_is_consumer(struct acpi_device *adev,
+ const struct lpss_device_links *link)
+{
+ return acpi_dev_hid_uid_match(adev, link->consumer_hid, link->consumer_uid);
+}
+
+struct hid_uid {
+ const char *hid;
+ const char *uid;
+};
+
+static int match_hid_uid(struct device *dev, const void *data)
+{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+ const struct hid_uid *id = data;
+
+ if (!adev)
+ return 0;
+
+ return acpi_dev_hid_uid_match(adev, id->hid, id->uid);
+}
+
+static struct device *acpi_lpss_find_device(const char *hid, const char *uid)
+{
+ struct device *dev;
+
+ struct hid_uid data = {
+ .hid = hid,
+ .uid = uid,
+ };
+
+ dev = bus_find_device(&platform_bus_type, NULL, &data, match_hid_uid);
+ if (dev)
+ return dev;
+
+ return bus_find_device(&pci_bus_type, NULL, &data, match_hid_uid);
+}
+
+static bool acpi_lpss_dep(struct acpi_device *adev, acpi_handle handle)
+{
+ struct acpi_handle_list dep_devices;
+ acpi_status status;
+ int i;
+
+ if (!acpi_has_method(adev->handle, "_DEP"))
+ return false;
+
+ status = acpi_evaluate_reference(adev->handle, "_DEP", NULL,
+ &dep_devices);
+ if (ACPI_FAILURE(status)) {
+ dev_dbg(&adev->dev, "Failed to evaluate _DEP.\n");
+ return false;
+ }
+
+ for (i = 0; i < dep_devices.count; i++) {
+ if (dep_devices.handles[i] == handle)
+ return true;
+ }
+
+ return false;
+}
+
+static void acpi_lpss_link_consumer(struct device *dev1,
+ const struct lpss_device_links *link)
+{
+ struct device *dev2;
+
+ dev2 = acpi_lpss_find_device(link->consumer_hid, link->consumer_uid);
+ if (!dev2)
+ return;
+
+ if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
+ || acpi_lpss_dep(ACPI_COMPANION(dev2), ACPI_HANDLE(dev1)))
+ device_link_add(dev2, dev1, link->flags);
+
+ put_device(dev2);
+}
+
+static void acpi_lpss_link_supplier(struct device *dev1,
+ const struct lpss_device_links *link)
+{
+ struct device *dev2;
+
+ dev2 = acpi_lpss_find_device(link->supplier_hid, link->supplier_uid);
+ if (!dev2)
+ return;
+
+ if ((link->dep_missing_ids && dmi_check_system(link->dep_missing_ids))
+ || acpi_lpss_dep(ACPI_COMPANION(dev1), ACPI_HANDLE(dev2)))
+ device_link_add(dev1, dev2, link->flags);
+
+ put_device(dev2);
+}
+
+static void acpi_lpss_create_device_links(struct acpi_device *adev,
+ struct platform_device *pdev)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(lpss_device_links); i++) {
+ const struct lpss_device_links *link = &lpss_device_links[i];
+
+ if (acpi_lpss_is_supplier(adev, link))
+ acpi_lpss_link_consumer(&pdev->dev, link);
+
+ if (acpi_lpss_is_consumer(adev, link))
+ acpi_lpss_link_supplier(&pdev->dev, link);
+ }
+}
+
+static int acpi_lpss_create_device(struct acpi_device *adev,
+ const struct acpi_device_id *id)
+{
+ const 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 = (const struct lpss_device_desc *)id->driver_data;
+ if (!dev_desc) {
+ pdev = acpi_create_platform_device(adev, NULL);
+ 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) {
+ /* Avoid acpi_bus_attach() instantiating a pdev for this dev. */
+ adev->pnp.type.platform_id = 0;
+ /* Skip the device, but continue the namespace scan. */
+ ret = 0;
+ goto err_out;
+ }
+
+ pdata->adev = adev;
+ 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.
+ */
+ acpi_device_fix_up_power(adev);
+
+ adev->driver_data = pdata;
+ pdev = acpi_create_platform_device(adev, dev_desc->properties);
+ if (!IS_ERR_OR_NULL(pdev)) {
+ acpi_lpss_create_device_links(adev, 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 const 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;
+
+ 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);
+ }
+}
+
+static void acpi_lpss_d3_to_d0_delay(struct lpss_private_data *pdata)
+{
+ /*
+ * 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. However some platforms like BSW does not need this delay.
+ */
+ unsigned int delay = 10; /* default 10ms delay */
+
+ if (pdata->dev_desc->flags & LPSS_NO_D3_DELAY)
+ delay = 0;
+
+ msleep(delay);
+}
+
+static int acpi_lpss_activate(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = acpi_dev_resume(dev);
+ if (ret)
+ return ret;
+
+ acpi_lpss_d3_to_d0_delay(pdata);
+
+ /*
+ * This is called only on ->probe() stage where a device is either in
+ * known state defined by BIOS or most likely powered off. Due to this
+ * we have to deassert reset line to be sure that ->probe() will
+ * recognize the device.
+ */
+ if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
+ lpss_deassert_reset(pdata);
+
+#ifdef CONFIG_PM
+ if (pdata->dev_desc->flags & LPSS_SAVE_CTX_ONCE)
+ acpi_lpss_save_ctx(dev, pdata);
+#endif
+
+ return 0;
+}
+
+static void acpi_lpss_dismiss(struct device *dev)
+{
+ acpi_dev_suspend(dev, false);
+}
+
+/* IOSF SB for LPSS island */
+#define LPSS_IOSF_UNIT_LPIOEP 0xA0
+#define LPSS_IOSF_UNIT_LPIO1 0xAB
+#define LPSS_IOSF_UNIT_LPIO2 0xAC
+
+#define LPSS_IOSF_PMCSR 0x84
+#define LPSS_PMCSR_D0 0
+#define LPSS_PMCSR_D3hot 3
+#define LPSS_PMCSR_Dx_MASK GENMASK(1, 0)
+
+#define LPSS_IOSF_GPIODEF0 0x154
+#define LPSS_GPIODEF0_DMA1_D3 BIT(2)
+#define LPSS_GPIODEF0_DMA2_D3 BIT(3)
+#define LPSS_GPIODEF0_DMA_D3_MASK GENMASK(3, 2)
+#define LPSS_GPIODEF0_DMA_LLP BIT(13)
+
+static DEFINE_MUTEX(lpss_iosf_mutex);
+static bool lpss_iosf_d3_entered = true;
+
+static void lpss_iosf_enter_d3_state(void)
+{
+ u32 value1 = 0;
+ u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
+ u32 value2 = LPSS_PMCSR_D3hot;
+ u32 mask2 = LPSS_PMCSR_Dx_MASK;
+ /*
+ * PMC provides an information about actual status of the LPSS devices.
+ * Here we read the values related to LPSS power island, i.e. LPSS
+ * devices, excluding both LPSS DMA controllers, along with SCC domain.
+ */
+ u32 func_dis, d3_sts_0, pmc_status;
+ int ret;
+
+ ret = pmc_atom_read(PMC_FUNC_DIS, &func_dis);
+ if (ret)
+ return;
+
+ mutex_lock(&lpss_iosf_mutex);
+
+ ret = pmc_atom_read(PMC_D3_STS_0, &d3_sts_0);
+ if (ret)
+ goto exit;
+
+ /*
+ * Get the status of entire LPSS power island per device basis.
+ * Shutdown both LPSS DMA controllers if and only if all other devices
+ * are already in D3hot.
+ */
+ pmc_status = (~(d3_sts_0 | func_dis)) & pmc_atom_d3_mask;
+ if (pmc_status)
+ goto exit;
+
+ iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
+ LPSS_IOSF_PMCSR, value2, mask2);
+
+ iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
+ LPSS_IOSF_PMCSR, value2, mask2);
+
+ iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
+ LPSS_IOSF_GPIODEF0, value1, mask1);
+
+ lpss_iosf_d3_entered = true;
+
+exit:
+ mutex_unlock(&lpss_iosf_mutex);
+}
+
+static void lpss_iosf_exit_d3_state(void)
+{
+ u32 value1 = LPSS_GPIODEF0_DMA1_D3 | LPSS_GPIODEF0_DMA2_D3 |
+ LPSS_GPIODEF0_DMA_LLP;
+ u32 mask1 = LPSS_GPIODEF0_DMA_D3_MASK | LPSS_GPIODEF0_DMA_LLP;
+ u32 value2 = LPSS_PMCSR_D0;
+ u32 mask2 = LPSS_PMCSR_Dx_MASK;
+
+ mutex_lock(&lpss_iosf_mutex);
+
+ if (!lpss_iosf_d3_entered)
+ goto exit;
+
+ lpss_iosf_d3_entered = false;
+
+ iosf_mbi_modify(LPSS_IOSF_UNIT_LPIOEP, MBI_CR_WRITE,
+ LPSS_IOSF_GPIODEF0, value1, mask1);
+
+ iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO2, MBI_CFG_WRITE,
+ LPSS_IOSF_PMCSR, value2, mask2);
+
+ iosf_mbi_modify(LPSS_IOSF_UNIT_LPIO1, MBI_CFG_WRITE,
+ LPSS_IOSF_PMCSR, value2, mask2);
+
+exit:
+ mutex_unlock(&lpss_iosf_mutex);
+}
+
+static int acpi_lpss_suspend(struct device *dev, bool wakeup)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ if (pdata->dev_desc->flags & LPSS_SAVE_CTX)
+ acpi_lpss_save_ctx(dev, pdata);
+
+ ret = acpi_dev_suspend(dev, wakeup);
+
+ /*
+ * This call must be last in the sequence, otherwise PMC will return
+ * wrong status for devices being about to be powered off. See
+ * lpss_iosf_enter_d3_state() for further information.
+ */
+ if (acpi_target_system_state() == ACPI_STATE_S0 &&
+ lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
+ lpss_iosf_enter_d3_state();
+
+ return ret;
+}
+
+static int acpi_lpss_resume(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ /*
+ * This call is kept first to be in symmetry with
+ * acpi_lpss_runtime_suspend() one.
+ */
+ if (lpss_quirks & LPSS_QUIRK_ALWAYS_POWER_ON && iosf_mbi_available())
+ lpss_iosf_exit_d3_state();
+
+ ret = acpi_dev_resume(dev);
+ if (ret)
+ return ret;
+
+ acpi_lpss_d3_to_d0_delay(pdata);
+
+ if (pdata->dev_desc->flags & (LPSS_SAVE_CTX | LPSS_SAVE_CTX_ONCE))
+ acpi_lpss_restore_ctx(dev, pdata);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int acpi_lpss_do_suspend_late(struct device *dev)
+{
+ int ret;
+
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ ret = pm_generic_suspend_late(dev);
+ return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
+}
+
+static int acpi_lpss_suspend_late(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ return acpi_lpss_do_suspend_late(dev);
+}
+
+static int acpi_lpss_suspend_noirq(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ if (pdata->dev_desc->resume_from_noirq) {
+ /*
+ * The driver's ->suspend_late callback will be invoked by
+ * acpi_lpss_do_suspend_late(), with the assumption that the
+ * driver really wanted to run that code in ->suspend_noirq, but
+ * it could not run after acpi_dev_suspend() and the driver
+ * expected the latter to be called in the "late" phase.
+ */
+ ret = acpi_lpss_do_suspend_late(dev);
+ if (ret)
+ return ret;
+ }
+
+ return acpi_subsys_suspend_noirq(dev);
+}
+
+static int acpi_lpss_do_resume_early(struct device *dev)
+{
+ int ret = acpi_lpss_resume(dev);
+
+ return ret ? ret : pm_generic_resume_early(dev);
+}
+
+static int acpi_lpss_resume_early(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ if (dev_pm_skip_resume(dev))
+ return 0;
+
+ return acpi_lpss_do_resume_early(dev);
+}
+
+static int acpi_lpss_resume_noirq(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ /* Follow acpi_subsys_resume_noirq(). */
+ if (dev_pm_skip_resume(dev))
+ return 0;
+
+ ret = pm_generic_resume_noirq(dev);
+ if (ret)
+ return ret;
+
+ if (!pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ /*
+ * The driver's ->resume_early callback will be invoked by
+ * acpi_lpss_do_resume_early(), with the assumption that the driver
+ * really wanted to run that code in ->resume_noirq, but it could not
+ * run before acpi_dev_resume() and the driver expected the latter to be
+ * called in the "early" phase.
+ */
+ return acpi_lpss_do_resume_early(dev);
+}
+
+static int acpi_lpss_do_restore_early(struct device *dev)
+{
+ int ret = acpi_lpss_resume(dev);
+
+ return ret ? ret : pm_generic_restore_early(dev);
+}
+
+static int acpi_lpss_restore_early(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ return acpi_lpss_do_restore_early(dev);
+}
+
+static int acpi_lpss_restore_noirq(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+ int ret;
+
+ ret = pm_generic_restore_noirq(dev);
+ if (ret)
+ return ret;
+
+ if (!pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ /* This is analogous to what happens in acpi_lpss_resume_noirq(). */
+ return acpi_lpss_do_restore_early(dev);
+}
+
+static int acpi_lpss_do_poweroff_late(struct device *dev)
+{
+ int ret = pm_generic_poweroff_late(dev);
+
+ return ret ? ret : acpi_lpss_suspend(dev, device_may_wakeup(dev));
+}
+
+static int acpi_lpss_poweroff_late(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ if (pdata->dev_desc->resume_from_noirq)
+ return 0;
+
+ return acpi_lpss_do_poweroff_late(dev);
+}
+
+static int acpi_lpss_poweroff_noirq(struct device *dev)
+{
+ struct lpss_private_data *pdata = acpi_driver_data(ACPI_COMPANION(dev));
+
+ if (dev_pm_skip_suspend(dev))
+ return 0;
+
+ if (pdata->dev_desc->resume_from_noirq) {
+ /* This is analogous to the acpi_lpss_suspend_noirq() case. */
+ int ret = acpi_lpss_do_poweroff_late(dev);
+ if (ret)
+ return ret;
+ }
+
+ return pm_generic_poweroff_noirq(dev);
+}
+#endif /* CONFIG_PM_SLEEP */
+
+static int acpi_lpss_runtime_suspend(struct device *dev)
+{
+ int ret = pm_generic_runtime_suspend(dev);
+
+ return ret ? ret : acpi_lpss_suspend(dev, true);
+}
+
+static int acpi_lpss_runtime_resume(struct device *dev)
+{
+ int ret = acpi_lpss_resume(dev);
+
+ return ret ? ret : pm_generic_runtime_resume(dev);
+}
+#endif /* CONFIG_PM */
+
+static struct dev_pm_domain acpi_lpss_pm_domain = {
+#ifdef CONFIG_PM
+ .activate = acpi_lpss_activate,
+ .dismiss = acpi_lpss_dismiss,
+#endif
+ .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,
+ .suspend_noirq = acpi_lpss_suspend_noirq,
+ .resume_noirq = acpi_lpss_resume_noirq,
+ .resume_early = acpi_lpss_resume_early,
+ .freeze = acpi_subsys_freeze,
+ .poweroff = acpi_subsys_poweroff,
+ .poweroff_late = acpi_lpss_poweroff_late,
+ .poweroff_noirq = acpi_lpss_poweroff_noirq,
+ .restore_noirq = acpi_lpss_restore_noirq,
+ .restore_early = acpi_lpss_restore_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_BIND_DRIVER:
+ dev_pm_domain_set(&pdev->dev, &acpi_lpss_pm_domain);
+ break;
+ case BUS_NOTIFY_DRIVER_NOT_BOUND:
+ case BUS_NOTIFY_UNBOUND_DRIVER:
+ dev_pm_domain_set(&pdev->dev, NULL);
+ break;
+ case BUS_NOTIFY_ADD_DEVICE:
+ dev_pm_domain_set(&pdev->dev, &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);
+ dev_pm_domain_set(&pdev->dev, 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)
+{
+ const struct x86_cpu_id *id;
+ int ret;
+
+ ret = lpt_clk_init();
+ if (ret)
+ return;
+
+ id = x86_match_cpu(lpss_cpu_ids);
+ if (id)
+ lpss_quirks |= LPSS_QUIRK_ALWAYS_POWER_ON;
+
+ 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 */