- 根目录:
- drivers
- acpi
- acpi_lpss.c
/*
* 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/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)
#define LPSS_NO_D3_DELAY BIT(5)
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 const struct lpss_device_desc lpt_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_CLK_DIVIDER | LPSS_LTR,
.prv_offset = 0x800,
};
static const struct lpss_device_desc lpt_i2c_dev_desc = {
.flags = LPSS_CLK | LPSS_CLK_GATE | LPSS_LTR,
.prv_offset = 0x800,
};
static const 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 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,
};
static const struct lpss_device_desc bsw_pwm_dev_desc = {
.flags = LPSS_SAVE_CTX | LPSS_NO_D3_DELAY,
};
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,
};
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,
};
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,
};
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,
};
static 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,
};
#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(bsw_pwm_dev_desc) },
{ "8086228A", LPSS_ADDR(bsw_uart_dev_desc) },
{ "8086228E", LPSS_ADDR(bsw_spi_dev_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 = 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)
{
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);
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, <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 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. 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);
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 = pm_complete_with_resume_check,
.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 */