summaryrefslogtreecommitdiffstats
path: root/drivers/platform/x86/dell/dcdbas.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/platform/x86/dell/dcdbas.c')
-rw-r--r--drivers/platform/x86/dell/dcdbas.c782
1 files changed, 782 insertions, 0 deletions
diff --git a/drivers/platform/x86/dell/dcdbas.c b/drivers/platform/x86/dell/dcdbas.c
new file mode 100644
index 000000000..0ecb7b164
--- /dev/null
+++ b/drivers/platform/x86/dell/dcdbas.c
@@ -0,0 +1,782 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * dcdbas.c: Dell Systems Management Base Driver
+ *
+ * The Dell Systems Management Base Driver provides a sysfs interface for
+ * systems management software to perform System Management Interrupts (SMIs)
+ * and Host Control Actions (power cycle or power off after OS shutdown) on
+ * Dell systems.
+ *
+ * See Documentation/driver-api/dcdbas.rst for more information.
+ *
+ * Copyright (C) 1995-2006 Dell Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/acpi.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmi.h>
+#include <linux/errno.h>
+#include <linux/cpu.h>
+#include <linux/gfp.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/mc146818rtc.h>
+#include <linux/module.h>
+#include <linux/reboot.h>
+#include <linux/sched.h>
+#include <linux/smp.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/mutex.h>
+
+#include "dcdbas.h"
+
+#define DRIVER_NAME "dcdbas"
+#define DRIVER_VERSION "5.6.0-3.4"
+#define DRIVER_DESCRIPTION "Dell Systems Management Base Driver"
+
+static struct platform_device *dcdbas_pdev;
+
+static unsigned long max_smi_data_buf_size = MAX_SMI_DATA_BUF_SIZE;
+static DEFINE_MUTEX(smi_data_lock);
+static u8 *bios_buffer;
+static struct smi_buffer smi_buf;
+
+static unsigned int host_control_action;
+static unsigned int host_control_smi_type;
+static unsigned int host_control_on_shutdown;
+
+static bool wsmt_enabled;
+
+int dcdbas_smi_alloc(struct smi_buffer *smi_buffer, unsigned long size)
+{
+ smi_buffer->virt = dma_alloc_coherent(&dcdbas_pdev->dev, size,
+ &smi_buffer->dma, GFP_KERNEL);
+ if (!smi_buffer->virt) {
+ dev_dbg(&dcdbas_pdev->dev,
+ "%s: failed to allocate memory size %lu\n",
+ __func__, size);
+ return -ENOMEM;
+ }
+ smi_buffer->size = size;
+
+ dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
+ __func__, (u32)smi_buffer->dma, smi_buffer->size);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(dcdbas_smi_alloc);
+
+void dcdbas_smi_free(struct smi_buffer *smi_buffer)
+{
+ if (!smi_buffer->virt)
+ return;
+
+ dev_dbg(&dcdbas_pdev->dev, "%s: phys: %x size: %lu\n",
+ __func__, (u32)smi_buffer->dma, smi_buffer->size);
+ dma_free_coherent(&dcdbas_pdev->dev, smi_buffer->size,
+ smi_buffer->virt, smi_buffer->dma);
+ smi_buffer->virt = NULL;
+ smi_buffer->dma = 0;
+ smi_buffer->size = 0;
+}
+EXPORT_SYMBOL_GPL(dcdbas_smi_free);
+
+/**
+ * smi_data_buf_free: free SMI data buffer
+ */
+static void smi_data_buf_free(void)
+{
+ if (!smi_buf.virt || wsmt_enabled)
+ return;
+
+ dcdbas_smi_free(&smi_buf);
+}
+
+/**
+ * smi_data_buf_realloc: grow SMI data buffer if needed
+ */
+static int smi_data_buf_realloc(unsigned long size)
+{
+ struct smi_buffer tmp;
+ int ret;
+
+ if (smi_buf.size >= size)
+ return 0;
+
+ if (size > max_smi_data_buf_size)
+ return -EINVAL;
+
+ /* new buffer is needed */
+ ret = dcdbas_smi_alloc(&tmp, size);
+ if (ret)
+ return ret;
+
+ /* memory zeroed by dma_alloc_coherent */
+ if (smi_buf.virt)
+ memcpy(tmp.virt, smi_buf.virt, smi_buf.size);
+
+ /* free any existing buffer */
+ smi_data_buf_free();
+
+ /* set up new buffer for use */
+ smi_buf = tmp;
+
+ return 0;
+}
+
+static ssize_t smi_data_buf_phys_addr_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%x\n", (u32)smi_buf.dma);
+}
+
+static ssize_t smi_data_buf_size_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%lu\n", smi_buf.size);
+}
+
+static ssize_t smi_data_buf_size_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ unsigned long buf_size;
+ ssize_t ret;
+
+ buf_size = simple_strtoul(buf, NULL, 10);
+
+ /* make sure SMI data buffer is at least buf_size */
+ mutex_lock(&smi_data_lock);
+ ret = smi_data_buf_realloc(buf_size);
+ mutex_unlock(&smi_data_lock);
+ if (ret)
+ return ret;
+
+ return count;
+}
+
+static ssize_t smi_data_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t pos, size_t count)
+{
+ ssize_t ret;
+
+ mutex_lock(&smi_data_lock);
+ ret = memory_read_from_buffer(buf, count, &pos, smi_buf.virt,
+ smi_buf.size);
+ mutex_unlock(&smi_data_lock);
+ return ret;
+}
+
+static ssize_t smi_data_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr,
+ char *buf, loff_t pos, size_t count)
+{
+ ssize_t ret;
+
+ if ((pos + count) > max_smi_data_buf_size)
+ return -EINVAL;
+
+ mutex_lock(&smi_data_lock);
+
+ ret = smi_data_buf_realloc(pos + count);
+ if (ret)
+ goto out;
+
+ memcpy(smi_buf.virt + pos, buf, count);
+ ret = count;
+out:
+ mutex_unlock(&smi_data_lock);
+ return ret;
+}
+
+static ssize_t host_control_action_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", host_control_action);
+}
+
+static ssize_t host_control_action_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ ssize_t ret;
+
+ /* make sure buffer is available for host control command */
+ mutex_lock(&smi_data_lock);
+ ret = smi_data_buf_realloc(sizeof(struct apm_cmd));
+ mutex_unlock(&smi_data_lock);
+ if (ret)
+ return ret;
+
+ host_control_action = simple_strtoul(buf, NULL, 10);
+ return count;
+}
+
+static ssize_t host_control_smi_type_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", host_control_smi_type);
+}
+
+static ssize_t host_control_smi_type_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ host_control_smi_type = simple_strtoul(buf, NULL, 10);
+ return count;
+}
+
+static ssize_t host_control_on_shutdown_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ return sprintf(buf, "%u\n", host_control_on_shutdown);
+}
+
+static ssize_t host_control_on_shutdown_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ host_control_on_shutdown = simple_strtoul(buf, NULL, 10);
+ return count;
+}
+
+static int raise_smi(void *par)
+{
+ struct smi_cmd *smi_cmd = par;
+
+ if (smp_processor_id() != 0) {
+ dev_dbg(&dcdbas_pdev->dev, "%s: failed to get CPU 0\n",
+ __func__);
+ return -EBUSY;
+ }
+
+ /* generate SMI */
+ /* inb to force posted write through and make SMI happen now */
+ asm volatile (
+ "outb %b0,%w1\n"
+ "inb %w1"
+ : /* no output args */
+ : "a" (smi_cmd->command_code),
+ "d" (smi_cmd->command_address),
+ "b" (smi_cmd->ebx),
+ "c" (smi_cmd->ecx)
+ : "memory"
+ );
+
+ return 0;
+}
+/**
+ * dcdbas_smi_request: generate SMI request
+ *
+ * Called with smi_data_lock.
+ */
+int dcdbas_smi_request(struct smi_cmd *smi_cmd)
+{
+ int ret;
+
+ if (smi_cmd->magic != SMI_CMD_MAGIC) {
+ dev_info(&dcdbas_pdev->dev, "%s: invalid magic value\n",
+ __func__);
+ return -EBADR;
+ }
+
+ /* SMI requires CPU 0 */
+ cpus_read_lock();
+ ret = smp_call_on_cpu(0, raise_smi, smi_cmd, true);
+ cpus_read_unlock();
+
+ return ret;
+}
+EXPORT_SYMBOL(dcdbas_smi_request);
+
+/**
+ * smi_request_store:
+ *
+ * The valid values are:
+ * 0: zero SMI data buffer
+ * 1: generate calling interface SMI
+ * 2: generate raw SMI
+ *
+ * User application writes smi_cmd to smi_data before telling driver
+ * to generate SMI.
+ */
+static ssize_t smi_request_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct smi_cmd *smi_cmd;
+ unsigned long val = simple_strtoul(buf, NULL, 10);
+ ssize_t ret;
+
+ mutex_lock(&smi_data_lock);
+
+ if (smi_buf.size < sizeof(struct smi_cmd)) {
+ ret = -ENODEV;
+ goto out;
+ }
+ smi_cmd = (struct smi_cmd *)smi_buf.virt;
+
+ switch (val) {
+ case 2:
+ /* Raw SMI */
+ ret = dcdbas_smi_request(smi_cmd);
+ if (!ret)
+ ret = count;
+ break;
+ case 1:
+ /*
+ * Calling Interface SMI
+ *
+ * Provide physical address of command buffer field within
+ * the struct smi_cmd to BIOS.
+ *
+ * Because the address that smi_cmd (smi_buf.virt) points to
+ * will be from memremap() of a non-memory address if WSMT
+ * is present, we can't use virt_to_phys() on smi_cmd, so
+ * we have to use the physical address that was saved when
+ * the virtual address for smi_cmd was received.
+ */
+ smi_cmd->ebx = (u32)smi_buf.dma +
+ offsetof(struct smi_cmd, command_buffer);
+ ret = dcdbas_smi_request(smi_cmd);
+ if (!ret)
+ ret = count;
+ break;
+ case 0:
+ memset(smi_buf.virt, 0, smi_buf.size);
+ ret = count;
+ break;
+ default:
+ ret = -EINVAL;
+ break;
+ }
+
+out:
+ mutex_unlock(&smi_data_lock);
+ return ret;
+}
+
+/**
+ * host_control_smi: generate host control SMI
+ *
+ * Caller must set up the host control command in smi_buf.virt.
+ */
+static int host_control_smi(void)
+{
+ struct apm_cmd *apm_cmd;
+ u8 *data;
+ unsigned long flags;
+ u32 num_ticks;
+ s8 cmd_status;
+ u8 index;
+
+ apm_cmd = (struct apm_cmd *)smi_buf.virt;
+ apm_cmd->status = ESM_STATUS_CMD_UNSUCCESSFUL;
+
+ switch (host_control_smi_type) {
+ case HC_SMITYPE_TYPE1:
+ spin_lock_irqsave(&rtc_lock, flags);
+ /* write SMI data buffer physical address */
+ data = (u8 *)&smi_buf.dma;
+ for (index = PE1300_CMOS_CMD_STRUCT_PTR;
+ index < (PE1300_CMOS_CMD_STRUCT_PTR + 4);
+ index++, data++) {
+ outb(index,
+ (CMOS_BASE_PORT + CMOS_PAGE2_INDEX_PORT_PIIX4));
+ outb(*data,
+ (CMOS_BASE_PORT + CMOS_PAGE2_DATA_PORT_PIIX4));
+ }
+
+ /* first set status to -1 as called by spec */
+ cmd_status = ESM_STATUS_CMD_UNSUCCESSFUL;
+ outb((u8) cmd_status, PCAT_APM_STATUS_PORT);
+
+ /* generate SMM call */
+ outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ /* wait a few to see if it executed */
+ num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
+ while ((s8)inb(PCAT_APM_STATUS_PORT) == ESM_STATUS_CMD_UNSUCCESSFUL) {
+ num_ticks--;
+ if (num_ticks == EXPIRED_TIMER)
+ return -ETIME;
+ }
+ break;
+
+ case HC_SMITYPE_TYPE2:
+ case HC_SMITYPE_TYPE3:
+ spin_lock_irqsave(&rtc_lock, flags);
+ /* write SMI data buffer physical address */
+ data = (u8 *)&smi_buf.dma;
+ for (index = PE1400_CMOS_CMD_STRUCT_PTR;
+ index < (PE1400_CMOS_CMD_STRUCT_PTR + 4);
+ index++, data++) {
+ outb(index, (CMOS_BASE_PORT + CMOS_PAGE1_INDEX_PORT));
+ outb(*data, (CMOS_BASE_PORT + CMOS_PAGE1_DATA_PORT));
+ }
+
+ /* generate SMM call */
+ if (host_control_smi_type == HC_SMITYPE_TYPE3)
+ outb(ESM_APM_CMD, PCAT_APM_CONTROL_PORT);
+ else
+ outb(ESM_APM_CMD, PE1400_APM_CONTROL_PORT);
+
+ /* restore RTC index pointer since it was written to above */
+ CMOS_READ(RTC_REG_C);
+ spin_unlock_irqrestore(&rtc_lock, flags);
+
+ /* read control port back to serialize write */
+ cmd_status = inb(PE1400_APM_CONTROL_PORT);
+
+ /* wait a few to see if it executed */
+ num_ticks = TIMEOUT_USEC_SHORT_SEMA_BLOCKING;
+ while (apm_cmd->status == ESM_STATUS_CMD_UNSUCCESSFUL) {
+ num_ticks--;
+ if (num_ticks == EXPIRED_TIMER)
+ return -ETIME;
+ }
+ break;
+
+ default:
+ dev_dbg(&dcdbas_pdev->dev, "%s: invalid SMI type %u\n",
+ __func__, host_control_smi_type);
+ return -ENOSYS;
+ }
+
+ return 0;
+}
+
+/**
+ * dcdbas_host_control: initiate host control
+ *
+ * This function is called by the driver after the system has
+ * finished shutting down if the user application specified a
+ * host control action to perform on shutdown. It is safe to
+ * use smi_buf.virt at this point because the system has finished
+ * shutting down and no userspace apps are running.
+ */
+static void dcdbas_host_control(void)
+{
+ struct apm_cmd *apm_cmd;
+ u8 action;
+
+ if (host_control_action == HC_ACTION_NONE)
+ return;
+
+ action = host_control_action;
+ host_control_action = HC_ACTION_NONE;
+
+ if (!smi_buf.virt) {
+ dev_dbg(&dcdbas_pdev->dev, "%s: no SMI buffer\n", __func__);
+ return;
+ }
+
+ if (smi_buf.size < sizeof(struct apm_cmd)) {
+ dev_dbg(&dcdbas_pdev->dev, "%s: SMI buffer too small\n",
+ __func__);
+ return;
+ }
+
+ apm_cmd = (struct apm_cmd *)smi_buf.virt;
+
+ /* power off takes precedence */
+ if (action & HC_ACTION_HOST_CONTROL_POWEROFF) {
+ apm_cmd->command = ESM_APM_POWER_CYCLE;
+ apm_cmd->reserved = 0;
+ *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 0;
+ host_control_smi();
+ } else if (action & HC_ACTION_HOST_CONTROL_POWERCYCLE) {
+ apm_cmd->command = ESM_APM_POWER_CYCLE;
+ apm_cmd->reserved = 0;
+ *((s16 *)&apm_cmd->parameters.shortreq.parm[0]) = (s16) 20;
+ host_control_smi();
+ }
+}
+
+/* WSMT */
+
+static u8 checksum(u8 *buffer, u8 length)
+{
+ u8 sum = 0;
+ u8 *end = buffer + length;
+
+ while (buffer < end)
+ sum += *buffer++;
+ return sum;
+}
+
+static inline struct smm_eps_table *check_eps_table(u8 *addr)
+{
+ struct smm_eps_table *eps = (struct smm_eps_table *)addr;
+
+ if (strncmp(eps->smm_comm_buff_anchor, SMM_EPS_SIG, 4) != 0)
+ return NULL;
+
+ if (checksum(addr, eps->length) != 0)
+ return NULL;
+
+ return eps;
+}
+
+static int dcdbas_check_wsmt(void)
+{
+ const struct dmi_device *dev = NULL;
+ struct acpi_table_wsmt *wsmt = NULL;
+ struct smm_eps_table *eps = NULL;
+ u64 bios_buf_paddr;
+ u64 remap_size;
+ u8 *addr;
+
+ acpi_get_table(ACPI_SIG_WSMT, 0, (struct acpi_table_header **)&wsmt);
+ if (!wsmt)
+ return 0;
+
+ /* Check if WSMT ACPI table shows that protection is enabled */
+ if (!(wsmt->protection_flags & ACPI_WSMT_FIXED_COMM_BUFFERS) ||
+ !(wsmt->protection_flags & ACPI_WSMT_COMM_BUFFER_NESTED_PTR_PROTECTION))
+ return 0;
+
+ /*
+ * BIOS could provide the address/size of the protected buffer
+ * in an SMBIOS string or in an EPS structure in 0xFxxxx.
+ */
+
+ /* Check SMBIOS for buffer address */
+ while ((dev = dmi_find_device(DMI_DEV_TYPE_OEM_STRING, NULL, dev)))
+ if (sscanf(dev->name, "30[%16llx;%8llx]", &bios_buf_paddr,
+ &remap_size) == 2)
+ goto remap;
+
+ /* Scan for EPS (entry point structure) */
+ for (addr = (u8 *)__va(0xf0000);
+ addr < (u8 *)__va(0x100000 - sizeof(struct smm_eps_table));
+ addr += 16) {
+ eps = check_eps_table(addr);
+ if (eps)
+ break;
+ }
+
+ if (!eps) {
+ dev_dbg(&dcdbas_pdev->dev, "found WSMT, but no firmware buffer found\n");
+ return -ENODEV;
+ }
+ bios_buf_paddr = eps->smm_comm_buff_addr;
+ remap_size = eps->num_of_4k_pages * PAGE_SIZE;
+
+remap:
+ /*
+ * Get physical address of buffer and map to virtual address.
+ * Table gives size in 4K pages, regardless of actual system page size.
+ */
+ if (upper_32_bits(bios_buf_paddr + 8)) {
+ dev_warn(&dcdbas_pdev->dev, "found WSMT, but buffer address is above 4GB\n");
+ return -EINVAL;
+ }
+ /*
+ * Limit remap size to MAX_SMI_DATA_BUF_SIZE + 8 (since the first 8
+ * bytes are used for a semaphore, not the data buffer itself).
+ */
+ if (remap_size > MAX_SMI_DATA_BUF_SIZE + 8)
+ remap_size = MAX_SMI_DATA_BUF_SIZE + 8;
+
+ bios_buffer = memremap(bios_buf_paddr, remap_size, MEMREMAP_WB);
+ if (!bios_buffer) {
+ dev_warn(&dcdbas_pdev->dev, "found WSMT, but failed to map buffer\n");
+ return -ENOMEM;
+ }
+
+ /* First 8 bytes is for a semaphore, not part of the smi_buf.virt */
+ smi_buf.dma = bios_buf_paddr + 8;
+ smi_buf.virt = bios_buffer + 8;
+ smi_buf.size = remap_size - 8;
+ max_smi_data_buf_size = smi_buf.size;
+ wsmt_enabled = true;
+ dev_info(&dcdbas_pdev->dev,
+ "WSMT found, using firmware-provided SMI buffer.\n");
+ return 1;
+}
+
+/**
+ * dcdbas_reboot_notify: handle reboot notification for host control
+ */
+static int dcdbas_reboot_notify(struct notifier_block *nb, unsigned long code,
+ void *unused)
+{
+ switch (code) {
+ case SYS_DOWN:
+ case SYS_HALT:
+ case SYS_POWER_OFF:
+ if (host_control_on_shutdown) {
+ /* firmware is going to perform host control action */
+ printk(KERN_WARNING "Please wait for shutdown "
+ "action to complete...\n");
+ dcdbas_host_control();
+ }
+ break;
+ }
+
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block dcdbas_reboot_nb = {
+ .notifier_call = dcdbas_reboot_notify,
+ .next = NULL,
+ .priority = INT_MIN
+};
+
+static DCDBAS_BIN_ATTR_RW(smi_data);
+
+static struct bin_attribute *dcdbas_bin_attrs[] = {
+ &bin_attr_smi_data,
+ NULL
+};
+
+static DCDBAS_DEV_ATTR_RW(smi_data_buf_size);
+static DCDBAS_DEV_ATTR_RO(smi_data_buf_phys_addr);
+static DCDBAS_DEV_ATTR_WO(smi_request);
+static DCDBAS_DEV_ATTR_RW(host_control_action);
+static DCDBAS_DEV_ATTR_RW(host_control_smi_type);
+static DCDBAS_DEV_ATTR_RW(host_control_on_shutdown);
+
+static struct attribute *dcdbas_dev_attrs[] = {
+ &dev_attr_smi_data_buf_size.attr,
+ &dev_attr_smi_data_buf_phys_addr.attr,
+ &dev_attr_smi_request.attr,
+ &dev_attr_host_control_action.attr,
+ &dev_attr_host_control_smi_type.attr,
+ &dev_attr_host_control_on_shutdown.attr,
+ NULL
+};
+
+static const struct attribute_group dcdbas_attr_group = {
+ .attrs = dcdbas_dev_attrs,
+ .bin_attrs = dcdbas_bin_attrs,
+};
+
+static int dcdbas_probe(struct platform_device *dev)
+{
+ int error;
+
+ host_control_action = HC_ACTION_NONE;
+ host_control_smi_type = HC_SMITYPE_NONE;
+
+ dcdbas_pdev = dev;
+
+ /* Check if ACPI WSMT table specifies protected SMI buffer address */
+ error = dcdbas_check_wsmt();
+ if (error < 0)
+ return error;
+
+ /*
+ * BIOS SMI calls require buffer addresses be in 32-bit address space.
+ * This is done by setting the DMA mask below.
+ */
+ error = dma_set_coherent_mask(&dcdbas_pdev->dev, DMA_BIT_MASK(32));
+ if (error)
+ return error;
+
+ error = sysfs_create_group(&dev->dev.kobj, &dcdbas_attr_group);
+ if (error)
+ return error;
+
+ register_reboot_notifier(&dcdbas_reboot_nb);
+
+ dev_info(&dev->dev, "%s (version %s)\n",
+ DRIVER_DESCRIPTION, DRIVER_VERSION);
+
+ return 0;
+}
+
+static int dcdbas_remove(struct platform_device *dev)
+{
+ unregister_reboot_notifier(&dcdbas_reboot_nb);
+ sysfs_remove_group(&dev->dev.kobj, &dcdbas_attr_group);
+
+ return 0;
+}
+
+static struct platform_driver dcdbas_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ },
+ .probe = dcdbas_probe,
+ .remove = dcdbas_remove,
+};
+
+static const struct platform_device_info dcdbas_dev_info __initconst = {
+ .name = DRIVER_NAME,
+ .id = PLATFORM_DEVID_NONE,
+ .dma_mask = DMA_BIT_MASK(32),
+};
+
+static struct platform_device *dcdbas_pdev_reg;
+
+/**
+ * dcdbas_init: initialize driver
+ */
+static int __init dcdbas_init(void)
+{
+ int error;
+
+ error = platform_driver_register(&dcdbas_driver);
+ if (error)
+ return error;
+
+ dcdbas_pdev_reg = platform_device_register_full(&dcdbas_dev_info);
+ if (IS_ERR(dcdbas_pdev_reg)) {
+ error = PTR_ERR(dcdbas_pdev_reg);
+ goto err_unregister_driver;
+ }
+
+ return 0;
+
+ err_unregister_driver:
+ platform_driver_unregister(&dcdbas_driver);
+ return error;
+}
+
+/**
+ * dcdbas_exit: perform driver cleanup
+ */
+static void __exit dcdbas_exit(void)
+{
+ /*
+ * make sure functions that use dcdbas_pdev are called
+ * before platform_device_unregister
+ */
+ unregister_reboot_notifier(&dcdbas_reboot_nb);
+
+ /*
+ * We have to free the buffer here instead of dcdbas_remove
+ * because only in module exit function we can be sure that
+ * all sysfs attributes belonging to this module have been
+ * released.
+ */
+ if (dcdbas_pdev)
+ smi_data_buf_free();
+ if (bios_buffer)
+ memunmap(bios_buffer);
+ platform_device_unregister(dcdbas_pdev_reg);
+ platform_driver_unregister(&dcdbas_driver);
+}
+
+subsys_initcall_sync(dcdbas_init);
+module_exit(dcdbas_exit);
+
+MODULE_DESCRIPTION(DRIVER_DESCRIPTION " (version " DRIVER_VERSION ")");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_AUTHOR("Dell Inc.");
+MODULE_LICENSE("GPL");
+/* Any System or BIOS claiming to be by Dell */
+MODULE_ALIAS("dmi:*:[bs]vnD[Ee][Ll][Ll]*:*");