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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /drivers/mfd/intel-lpss.c
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'drivers/mfd/intel-lpss.c')
-rw-r--r--drivers/mfd/intel-lpss.c566
1 files changed, 566 insertions, 0 deletions
diff --git a/drivers/mfd/intel-lpss.c b/drivers/mfd/intel-lpss.c
new file mode 100644
index 000000000..63d6694f7
--- /dev/null
+++ b/drivers/mfd/intel-lpss.c
@@ -0,0 +1,566 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel Sunrisepoint LPSS core support.
+ *
+ * Copyright (C) 2015, Intel Corporation
+ *
+ * Authors: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+ * Mika Westerberg <mika.westerberg@linux.intel.com>
+ * Heikki Krogerus <heikki.krogerus@linux.intel.com>
+ * Jarkko Nikula <jarkko.nikula@linux.intel.com>
+ */
+
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/clkdev.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gfp_types.h>
+#include <linux/idr.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/pm.h>
+#include <linux/pm_qos.h>
+#include <linux/pm_runtime.h>
+#include <linux/sprintf.h>
+#include <linux/types.h>
+
+#include <linux/io-64-nonatomic-lo-hi.h>
+
+#include <linux/dma/idma64.h>
+
+#include "intel-lpss.h"
+
+struct dentry;
+
+#define LPSS_DEV_OFFSET 0x000
+#define LPSS_DEV_SIZE 0x200
+#define LPSS_PRIV_OFFSET 0x200
+#define LPSS_PRIV_SIZE 0x100
+#define LPSS_PRIV_REG_COUNT (LPSS_PRIV_SIZE / 4)
+#define LPSS_IDMA64_OFFSET 0x800
+#define LPSS_IDMA64_SIZE 0x800
+
+/* Offsets from lpss->priv */
+#define LPSS_PRIV_RESETS 0x04
+#define LPSS_PRIV_RESETS_IDMA BIT(2)
+#define LPSS_PRIV_RESETS_FUNC 0x3
+
+#define LPSS_PRIV_ACTIVELTR 0x10
+#define LPSS_PRIV_IDLELTR 0x14
+
+#define LPSS_PRIV_LTR_REQ BIT(15)
+#define LPSS_PRIV_LTR_SCALE_MASK GENMASK(11, 10)
+#define LPSS_PRIV_LTR_SCALE_1US (2 << 10)
+#define LPSS_PRIV_LTR_SCALE_32US (3 << 10)
+#define LPSS_PRIV_LTR_VALUE_MASK GENMASK(9, 0)
+
+#define LPSS_PRIV_SSP_REG 0x20
+#define LPSS_PRIV_SSP_REG_DIS_DMA_FIN BIT(0)
+
+#define LPSS_PRIV_REMAP_ADDR 0x40
+
+#define LPSS_PRIV_CAPS 0xfc
+#define LPSS_PRIV_CAPS_NO_IDMA BIT(8)
+#define LPSS_PRIV_CAPS_TYPE_MASK GENMASK(7, 4)
+#define LPSS_PRIV_CAPS_TYPE_SHIFT 4
+
+/* This matches the type field in CAPS register */
+enum intel_lpss_dev_type {
+ LPSS_DEV_I2C = 0,
+ LPSS_DEV_UART,
+ LPSS_DEV_SPI,
+};
+
+struct intel_lpss {
+ const struct intel_lpss_platform_info *info;
+ enum intel_lpss_dev_type type;
+ struct clk *clk;
+ struct clk_lookup *clock;
+ struct mfd_cell *cell;
+ struct device *dev;
+ void __iomem *priv;
+ u32 priv_ctx[LPSS_PRIV_REG_COUNT];
+ int devid;
+ u32 caps;
+ u32 active_ltr;
+ u32 idle_ltr;
+ struct dentry *debugfs;
+};
+
+static const struct resource intel_lpss_dev_resources[] = {
+ DEFINE_RES_MEM_NAMED(LPSS_DEV_OFFSET, LPSS_DEV_SIZE, "lpss_dev"),
+ DEFINE_RES_MEM_NAMED(LPSS_PRIV_OFFSET, LPSS_PRIV_SIZE, "lpss_priv"),
+ DEFINE_RES_IRQ(0),
+};
+
+static const struct resource intel_lpss_idma64_resources[] = {
+ DEFINE_RES_MEM(LPSS_IDMA64_OFFSET, LPSS_IDMA64_SIZE),
+ DEFINE_RES_IRQ(0),
+};
+
+/*
+ * Cells needs to be ordered so that the iDMA is created first. This is
+ * because we need to be sure the DMA is available when the host controller
+ * driver is probed.
+ */
+static const struct mfd_cell intel_lpss_idma64_cell = {
+ .name = LPSS_IDMA64_DRIVER_NAME,
+ .num_resources = ARRAY_SIZE(intel_lpss_idma64_resources),
+ .resources = intel_lpss_idma64_resources,
+};
+
+static const struct mfd_cell intel_lpss_i2c_cell = {
+ .name = "i2c_designware",
+ .num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
+ .resources = intel_lpss_dev_resources,
+};
+
+static const struct mfd_cell intel_lpss_uart_cell = {
+ .name = "dw-apb-uart",
+ .num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
+ .resources = intel_lpss_dev_resources,
+};
+
+static const struct mfd_cell intel_lpss_spi_cell = {
+ .name = "pxa2xx-spi",
+ .num_resources = ARRAY_SIZE(intel_lpss_dev_resources),
+ .resources = intel_lpss_dev_resources,
+};
+
+static DEFINE_IDA(intel_lpss_devid_ida);
+static struct dentry *intel_lpss_debugfs;
+
+static void intel_lpss_cache_ltr(struct intel_lpss *lpss)
+{
+ lpss->active_ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
+ lpss->idle_ltr = readl(lpss->priv + LPSS_PRIV_IDLELTR);
+}
+
+static int intel_lpss_debugfs_add(struct intel_lpss *lpss)
+{
+ struct dentry *dir;
+
+ dir = debugfs_create_dir(dev_name(lpss->dev), intel_lpss_debugfs);
+ if (IS_ERR(dir))
+ return PTR_ERR(dir);
+
+ /* Cache the values into lpss structure */
+ intel_lpss_cache_ltr(lpss);
+
+ debugfs_create_x32("capabilities", S_IRUGO, dir, &lpss->caps);
+ debugfs_create_x32("active_ltr", S_IRUGO, dir, &lpss->active_ltr);
+ debugfs_create_x32("idle_ltr", S_IRUGO, dir, &lpss->idle_ltr);
+
+ lpss->debugfs = dir;
+ return 0;
+}
+
+static void intel_lpss_debugfs_remove(struct intel_lpss *lpss)
+{
+ debugfs_remove_recursive(lpss->debugfs);
+}
+
+static void intel_lpss_ltr_set(struct device *dev, s32 val)
+{
+ struct intel_lpss *lpss = dev_get_drvdata(dev);
+ u32 ltr;
+
+ /*
+ * Program latency tolerance (LTR) accordingly what has been asked
+ * by the PM QoS layer or disable it in case we were passed
+ * negative value or PM_QOS_LATENCY_ANY.
+ */
+ ltr = readl(lpss->priv + LPSS_PRIV_ACTIVELTR);
+
+ if (val == PM_QOS_LATENCY_ANY || val < 0) {
+ ltr &= ~LPSS_PRIV_LTR_REQ;
+ } else {
+ ltr |= LPSS_PRIV_LTR_REQ;
+ ltr &= ~LPSS_PRIV_LTR_SCALE_MASK;
+ ltr &= ~LPSS_PRIV_LTR_VALUE_MASK;
+
+ if (val > LPSS_PRIV_LTR_VALUE_MASK)
+ ltr |= LPSS_PRIV_LTR_SCALE_32US | val >> 5;
+ else
+ ltr |= LPSS_PRIV_LTR_SCALE_1US | val;
+ }
+
+ if (ltr == lpss->active_ltr)
+ return;
+
+ writel(ltr, lpss->priv + LPSS_PRIV_ACTIVELTR);
+ writel(ltr, lpss->priv + LPSS_PRIV_IDLELTR);
+
+ /* Cache the values into lpss structure */
+ intel_lpss_cache_ltr(lpss);
+}
+
+static void intel_lpss_ltr_expose(struct intel_lpss *lpss)
+{
+ lpss->dev->power.set_latency_tolerance = intel_lpss_ltr_set;
+ dev_pm_qos_expose_latency_tolerance(lpss->dev);
+}
+
+static void intel_lpss_ltr_hide(struct intel_lpss *lpss)
+{
+ dev_pm_qos_hide_latency_tolerance(lpss->dev);
+ lpss->dev->power.set_latency_tolerance = NULL;
+}
+
+static int intel_lpss_assign_devs(struct intel_lpss *lpss)
+{
+ const struct mfd_cell *cell;
+ unsigned int type;
+
+ type = lpss->caps & LPSS_PRIV_CAPS_TYPE_MASK;
+ type >>= LPSS_PRIV_CAPS_TYPE_SHIFT;
+
+ switch (type) {
+ case LPSS_DEV_I2C:
+ cell = &intel_lpss_i2c_cell;
+ break;
+ case LPSS_DEV_UART:
+ cell = &intel_lpss_uart_cell;
+ break;
+ case LPSS_DEV_SPI:
+ cell = &intel_lpss_spi_cell;
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ lpss->cell = devm_kmemdup(lpss->dev, cell, sizeof(*cell), GFP_KERNEL);
+ if (!lpss->cell)
+ return -ENOMEM;
+
+ lpss->type = type;
+
+ return 0;
+}
+
+static bool intel_lpss_has_idma(const struct intel_lpss *lpss)
+{
+ return (lpss->caps & LPSS_PRIV_CAPS_NO_IDMA) == 0;
+}
+
+static void intel_lpss_set_remap_addr(const struct intel_lpss *lpss)
+{
+ resource_size_t addr = lpss->info->mem->start;
+
+ lo_hi_writeq(addr, lpss->priv + LPSS_PRIV_REMAP_ADDR);
+}
+
+static void intel_lpss_deassert_reset(const struct intel_lpss *lpss)
+{
+ u32 value = LPSS_PRIV_RESETS_FUNC | LPSS_PRIV_RESETS_IDMA;
+
+ /* Bring out the device from reset */
+ writel(value, lpss->priv + LPSS_PRIV_RESETS);
+}
+
+static void intel_lpss_init_dev(const struct intel_lpss *lpss)
+{
+ u32 value = LPSS_PRIV_SSP_REG_DIS_DMA_FIN;
+
+ /* Set the device in reset state */
+ writel(0, lpss->priv + LPSS_PRIV_RESETS);
+
+ intel_lpss_deassert_reset(lpss);
+
+ intel_lpss_set_remap_addr(lpss);
+
+ if (!intel_lpss_has_idma(lpss))
+ return;
+
+ /* Make sure that SPI multiblock DMA transfers are re-enabled */
+ if (lpss->type == LPSS_DEV_SPI)
+ writel(value, lpss->priv + LPSS_PRIV_SSP_REG);
+}
+
+static void intel_lpss_unregister_clock_tree(struct clk *clk)
+{
+ struct clk *parent;
+
+ while (clk) {
+ parent = clk_get_parent(clk);
+ clk_unregister(clk);
+ clk = parent;
+ }
+}
+
+static int intel_lpss_register_clock_divider(struct intel_lpss *lpss,
+ const char *devname,
+ struct clk **clk)
+{
+ char name[32];
+ struct clk *tmp = *clk;
+ int ret;
+
+ snprintf(name, sizeof(name), "%s-enable", devname);
+ tmp = clk_register_gate(NULL, name, __clk_get_name(tmp), 0,
+ lpss->priv, 0, 0, NULL);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
+
+ snprintf(name, sizeof(name), "%s-div", devname);
+ tmp = clk_register_fractional_divider(NULL, name, __clk_get_name(tmp),
+ 0, lpss->priv, 1, 15, 16, 15,
+ CLK_FRAC_DIVIDER_POWER_OF_TWO_PS,
+ NULL);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
+ *clk = tmp;
+
+ if (lpss->info->quirks & QUIRK_CLOCK_DIVIDER_UNITY) {
+ ret = clk_set_rate(tmp, lpss->info->clk_rate);
+ if (ret)
+ return ret;
+ }
+
+ snprintf(name, sizeof(name), "%s-update", devname);
+ tmp = clk_register_gate(NULL, name, __clk_get_name(tmp),
+ CLK_SET_RATE_PARENT, lpss->priv, 31, 0, NULL);
+ if (IS_ERR(tmp))
+ return PTR_ERR(tmp);
+ *clk = tmp;
+
+ return 0;
+}
+
+static int intel_lpss_register_clock(struct intel_lpss *lpss)
+{
+ const struct mfd_cell *cell = lpss->cell;
+ struct clk *clk;
+ char devname[24];
+ int ret;
+
+ if (!lpss->info->clk_rate)
+ return 0;
+
+ /* Root clock */
+ clk = clk_register_fixed_rate(NULL, dev_name(lpss->dev), NULL, 0,
+ lpss->info->clk_rate);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ snprintf(devname, sizeof(devname), "%s.%d", cell->name, lpss->devid);
+
+ /*
+ * Support for clock divider only if it has some preset value.
+ * Otherwise we assume that the divider is not used.
+ */
+ if (lpss->type != LPSS_DEV_I2C) {
+ ret = intel_lpss_register_clock_divider(lpss, devname, &clk);
+ if (ret)
+ goto err_clk_register;
+ }
+
+ ret = -ENOMEM;
+
+ /* Clock for the host controller */
+ lpss->clock = clkdev_create(clk, lpss->info->clk_con_id, "%s", devname);
+ if (!lpss->clock)
+ goto err_clk_register;
+
+ lpss->clk = clk;
+
+ return 0;
+
+err_clk_register:
+ intel_lpss_unregister_clock_tree(clk);
+
+ return ret;
+}
+
+static void intel_lpss_unregister_clock(struct intel_lpss *lpss)
+{
+ if (IS_ERR_OR_NULL(lpss->clk))
+ return;
+
+ clkdev_drop(lpss->clock);
+ intel_lpss_unregister_clock_tree(lpss->clk);
+}
+
+int intel_lpss_probe(struct device *dev,
+ const struct intel_lpss_platform_info *info)
+{
+ struct intel_lpss *lpss;
+ int ret;
+
+ if (!info || !info->mem)
+ return -EINVAL;
+
+ if (info->irq < 0)
+ return info->irq;
+
+ lpss = devm_kzalloc(dev, sizeof(*lpss), GFP_KERNEL);
+ if (!lpss)
+ return -ENOMEM;
+
+ lpss->priv = devm_ioremap_uc(dev, info->mem->start + LPSS_PRIV_OFFSET,
+ LPSS_PRIV_SIZE);
+ if (!lpss->priv)
+ return -ENOMEM;
+
+ lpss->info = info;
+ lpss->dev = dev;
+ lpss->caps = readl(lpss->priv + LPSS_PRIV_CAPS);
+
+ dev_set_drvdata(dev, lpss);
+
+ ret = intel_lpss_assign_devs(lpss);
+ if (ret)
+ return ret;
+
+ lpss->cell->swnode = info->swnode;
+ lpss->cell->ignore_resource_conflicts = info->quirks & QUIRK_IGNORE_RESOURCE_CONFLICTS;
+
+ intel_lpss_init_dev(lpss);
+
+ lpss->devid = ida_alloc(&intel_lpss_devid_ida, GFP_KERNEL);
+ if (lpss->devid < 0)
+ return lpss->devid;
+
+ ret = intel_lpss_register_clock(lpss);
+ if (ret)
+ goto err_clk_register;
+
+ intel_lpss_ltr_expose(lpss);
+
+ ret = intel_lpss_debugfs_add(lpss);
+ if (ret)
+ dev_warn(dev, "Failed to create debugfs entries\n");
+
+ if (intel_lpss_has_idma(lpss)) {
+ ret = mfd_add_devices(dev, lpss->devid, &intel_lpss_idma64_cell,
+ 1, info->mem, info->irq, NULL);
+ if (ret)
+ dev_warn(dev, "Failed to add %s, fallback to PIO\n",
+ LPSS_IDMA64_DRIVER_NAME);
+ }
+
+ ret = mfd_add_devices(dev, lpss->devid, lpss->cell,
+ 1, info->mem, info->irq, NULL);
+ if (ret)
+ goto err_remove_ltr;
+
+ dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
+
+ return 0;
+
+err_remove_ltr:
+ intel_lpss_debugfs_remove(lpss);
+ intel_lpss_ltr_hide(lpss);
+ intel_lpss_unregister_clock(lpss);
+
+err_clk_register:
+ ida_free(&intel_lpss_devid_ida, lpss->devid);
+
+ return ret;
+}
+EXPORT_SYMBOL_NS_GPL(intel_lpss_probe, "INTEL_LPSS");
+
+void intel_lpss_remove(struct device *dev)
+{
+ struct intel_lpss *lpss = dev_get_drvdata(dev);
+
+ mfd_remove_devices(dev);
+ intel_lpss_debugfs_remove(lpss);
+ intel_lpss_ltr_hide(lpss);
+ intel_lpss_unregister_clock(lpss);
+ ida_free(&intel_lpss_devid_ida, lpss->devid);
+}
+EXPORT_SYMBOL_NS_GPL(intel_lpss_remove, "INTEL_LPSS");
+
+static int resume_lpss_device(struct device *dev, void *data)
+{
+ if (!dev_pm_smart_suspend(dev))
+ pm_runtime_resume(dev);
+
+ return 0;
+}
+
+static int intel_lpss_prepare(struct device *dev)
+{
+ /*
+ * Resume both child devices before entering system sleep. This
+ * ensures that they are in proper state before they get suspended.
+ */
+ device_for_each_child_reverse(dev, NULL, resume_lpss_device);
+ return 0;
+}
+
+static int intel_lpss_suspend(struct device *dev)
+{
+ struct intel_lpss *lpss = dev_get_drvdata(dev);
+ unsigned int i;
+
+ /* Save device context */
+ for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
+ lpss->priv_ctx[i] = readl(lpss->priv + i * 4);
+
+ /*
+ * If the device type is not UART, then put the controller into
+ * reset. UART cannot be put into reset since S3/S0ix fail when
+ * no_console_suspend flag is enabled.
+ */
+ if (lpss->type != LPSS_DEV_UART)
+ writel(0, lpss->priv + LPSS_PRIV_RESETS);
+
+ return 0;
+}
+
+static int intel_lpss_resume(struct device *dev)
+{
+ struct intel_lpss *lpss = dev_get_drvdata(dev);
+ unsigned int i;
+
+ intel_lpss_deassert_reset(lpss);
+
+ /* Restore device context */
+ for (i = 0; i < LPSS_PRIV_REG_COUNT; i++)
+ writel(lpss->priv_ctx[i], lpss->priv + i * 4);
+
+ return 0;
+}
+
+EXPORT_NS_GPL_DEV_PM_OPS(intel_lpss_pm_ops, INTEL_LPSS) = {
+ .prepare = pm_sleep_ptr(&intel_lpss_prepare),
+ LATE_SYSTEM_SLEEP_PM_OPS(intel_lpss_suspend, intel_lpss_resume)
+ RUNTIME_PM_OPS(intel_lpss_suspend, intel_lpss_resume, NULL)
+};
+
+static int __init intel_lpss_init(void)
+{
+ intel_lpss_debugfs = debugfs_create_dir("intel_lpss", NULL);
+ return 0;
+}
+module_init(intel_lpss_init);
+
+static void __exit intel_lpss_exit(void)
+{
+ ida_destroy(&intel_lpss_devid_ida);
+ debugfs_remove(intel_lpss_debugfs);
+}
+module_exit(intel_lpss_exit);
+
+MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>");
+MODULE_AUTHOR("Jarkko Nikula <jarkko.nikula@linux.intel.com>");
+MODULE_DESCRIPTION("Intel LPSS core driver");
+MODULE_LICENSE("GPL v2");
+/*
+ * Ensure the DMA driver is loaded before the host controller device appears,
+ * so that the host controller driver can request its DMA channels as early
+ * as possible.
+ *
+ * If the DMA module is not there that's OK as well.
+ */
+MODULE_SOFTDEP("pre: platform:" LPSS_IDMA64_DRIVER_NAME);