Revert "ACPI / SBS: Add 5 us delay to fix SBS hangs on MacBook"

Revert commit 3349fb64b292 (ACPI / SBS: Add 5 us delay to fix SBS
hangs on MacBook), since the delay introduced by it is not necessary
any more after commit add68d6aa9e2 (ACPI / SMBus: Fix boot stalls /
high CPU caused by reentrant code).

Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 0 insertions, 22 deletions

diff --git a/drivers/acpi/sbshc.c b/drivers/acpi/sbshc.c
index e2900518cf7e..2fa8304171e0 100644
--- a/drivers/acpi/sbshc.c
+++ b/drivers/acpi/sbshc.c
@@ -14,7 +14,6 @@
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/interrupt.h>
-#include <linux/dmi.h>
 #include "sbshc.h"
 
 #define PREFIX "ACPI: "
@@ -89,8 +88,6 @@ enum acpi_smb_offset {
         ACPI_SMB_ALARM_DATA = 0x26,     /* 2 bytes alarm data */
 };
 
-static bool macbook;
-
 static inline int smb_hc_read(struct acpi_smb_hc *hc, u8 address, u8 *data)
 {
         return ec_read(hc->offset + address, data);
@@ -121,8 +118,6 @@ static int acpi_smbus_transaction(struct acpi_smb_hc *hc, u8 protocol,
 
         mutex_lock(&hc->lock);
         hc->done = false;
-        if (macbook)
-                udelay(5);
         if (smb_hc_read(hc, ACPI_SMB_PROTOCOL, &temp))
                 goto end;
         if (temp) {
@@ -250,29 +245,12 @@ extern int acpi_ec_add_query_handler(struct acpi_ec *ec, u8 query_bit,
                               acpi_handle handle, acpi_ec_query_func func,
                               void *data);
 
-static int macbook_dmi_match(const struct dmi_system_id *d)
-{
-        pr_debug("Detected MacBook, enabling workaround\n");
-        macbook = true;
-        return 0;
-}
-
-static struct dmi_system_id acpi_smbus_dmi_table[] = {
-        { macbook_dmi_match, "Apple MacBook", {
-          DMI_MATCH(DMI_BOARD_VENDOR, "Apple"),
-          DMI_MATCH(DMI_PRODUCT_NAME, "MacBook") },
-        },
-        { },
-};
-
 static int acpi_smbus_hc_add(struct acpi_device *device)
 {
         int status;
         unsigned long long val;
         struct acpi_smb_hc *hc;
 
-        dmi_check_system(acpi_smbus_dmi_table);
-
         if (!device)
                 return -EINVAL;