--- /dev/null
+From 9862b43624a5450a097cc4122732857b869dbbca Mon Sep 17 00:00:00 2001
+From: Mario Limonciello <mario.limonciello@dell.com>
+Date: Wed, 31 Jan 2018 11:47:35 -0600
+Subject: platform/x86: dell-laptop: Allocate buffer on heap rather than globally
+
+From: Mario Limonciello <mario.limonciello@dell.com>
+
+commit 9862b43624a5450a097cc4122732857b869dbbca upstream.
+
+There is no longer a need for the buffer to be defined in
+first 4GB physical address space.
+
+Furthermore there may be race conditions with multiple different functions
+working on a module wide buffer causing incorrect results.
+
+Fixes: 549b4930f057658dc50d8010e66219233119a4d8
+Suggested-by: Pali Rohar <pali.rohar@gmail.com>
+Signed-off-by: Mario Limonciello <mario.limonciello@dell.com>
+Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+
+---
+ drivers/platform/x86/dell-laptop.c | 188 ++++++++++++++++++++-----------------
+ 1 file changed, 103 insertions(+), 85 deletions(-)
+
+--- a/drivers/platform/x86/dell-laptop.c
++++ b/drivers/platform/x86/dell-laptop.c
+@@ -78,7 +78,6 @@ static struct platform_driver platform_d
+ }
+ };
+
+-static struct calling_interface_buffer *buffer;
+ static struct platform_device *platform_device;
+ static struct backlight_device *dell_backlight_device;
+ static struct rfkill *wifi_rfkill;
+@@ -286,7 +285,8 @@ static const struct dmi_system_id dell_q
+ { }
+ };
+
+-void dell_set_arguments(u32 arg0, u32 arg1, u32 arg2, u32 arg3)
++static void dell_fill_request(struct calling_interface_buffer *buffer,
++ u32 arg0, u32 arg1, u32 arg2, u32 arg3)
+ {
+ memset(buffer, 0, sizeof(struct calling_interface_buffer));
+ buffer->input[0] = arg0;
+@@ -295,7 +295,8 @@ void dell_set_arguments(u32 arg0, u32 ar
+ buffer->input[3] = arg3;
+ }
+
+-int dell_send_request(u16 class, u16 select)
++static int dell_send_request(struct calling_interface_buffer *buffer,
++ u16 class, u16 select)
+ {
+ int ret;
+
+@@ -432,21 +433,22 @@ static int dell_rfkill_set(void *data, b
+ int disable = blocked ? 1 : 0;
+ unsigned long radio = (unsigned long)data;
+ int hwswitch_bit = (unsigned long)data - 1;
++ struct calling_interface_buffer buffer;
+ int hwswitch;
+ int status;
+ int ret;
+
+- dell_set_arguments(0, 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+ if (ret)
+ return ret;
+- status = buffer->output[1];
++ status = buffer.output[1];
+
+- dell_set_arguments(0x2, 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer, 0x2, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+ if (ret)
+ return ret;
+- hwswitch = buffer->output[1];
++ hwswitch = buffer.output[1];
+
+ /* If the hardware switch controls this radio, and the hardware
+ switch is disabled, always disable the radio */
+@@ -454,8 +456,8 @@ static int dell_rfkill_set(void *data, b
+ (status & BIT(0)) && !(status & BIT(16)))
+ disable = 1;
+
+- dell_set_arguments(1 | (radio<<8) | (disable << 16), 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer, 1 | (radio<<8) | (disable << 16), 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+ return ret;
+ }
+
+@@ -464,9 +466,11 @@ static void dell_rfkill_update_sw_state(
+ {
+ if (status & BIT(0)) {
+ /* Has hw-switch, sync sw_state to BIOS */
++ struct calling_interface_buffer buffer;
+ int block = rfkill_blocked(rfkill);
+- dell_set_arguments(1 | (radio << 8) | (block << 16), 0, 0, 0);
+- dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer,
++ 1 | (radio << 8) | (block << 16), 0, 0, 0);
++ dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+ } else {
+ /* No hw-switch, sync BIOS state to sw_state */
+ rfkill_set_sw_state(rfkill, !!(status & BIT(radio + 16)));
+@@ -483,21 +487,22 @@ static void dell_rfkill_update_hw_state(
+ static void dell_rfkill_query(struct rfkill *rfkill, void *data)
+ {
+ int radio = ((unsigned long)data & 0xF);
++ struct calling_interface_buffer buffer;
+ int hwswitch;
+ int status;
+ int ret;
+
+- dell_set_arguments(0, 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
+- status = buffer->output[1];
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
++ status = buffer.output[1];
+
+ if (ret != 0 || !(status & BIT(0))) {
+ return;
+ }
+
+- dell_set_arguments(0, 0x2, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
+- hwswitch = buffer->output[1];
++ dell_fill_request(&buffer, 0, 0x2, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
++ hwswitch = buffer.output[1];
+
+ if (ret != 0)
+ return;
+@@ -514,22 +519,23 @@ static struct dentry *dell_laptop_dir;
+
+ static int dell_debugfs_show(struct seq_file *s, void *data)
+ {
++ struct calling_interface_buffer buffer;
+ int hwswitch_state;
+ int hwswitch_ret;
+ int status;
+ int ret;
+
+- dell_set_arguments(0, 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+ if (ret)
+ return ret;
+- status = buffer->output[1];
++ status = buffer.output[1];
+
+- dell_set_arguments(0, 0x2, 0, 0);
+- hwswitch_ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer, 0, 0x2, 0, 0);
++ hwswitch_ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+ if (hwswitch_ret)
+ return hwswitch_ret;
+- hwswitch_state = buffer->output[1];
++ hwswitch_state = buffer.output[1];
+
+ seq_printf(s, "return:\t%d\n", ret);
+ seq_printf(s, "status:\t0x%X\n", status);
+@@ -610,22 +616,23 @@ static const struct file_operations dell
+
+ static void dell_update_rfkill(struct work_struct *ignored)
+ {
++ struct calling_interface_buffer buffer;
+ int hwswitch = 0;
+ int status;
+ int ret;
+
+- dell_set_arguments(0, 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
+- status = buffer->output[1];
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
++ status = buffer.output[1];
+
+ if (ret != 0)
+ return;
+
+- dell_set_arguments(0, 0x2, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
++ dell_fill_request(&buffer, 0, 0x2, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
+
+ if (ret == 0 && (status & BIT(0)))
+- hwswitch = buffer->output[1];
++ hwswitch = buffer.output[1];
+
+ if (wifi_rfkill) {
+ dell_rfkill_update_hw_state(wifi_rfkill, 1, status, hwswitch);
+@@ -683,6 +690,7 @@ static struct notifier_block dell_laptop
+
+ static int __init dell_setup_rfkill(void)
+ {
++ struct calling_interface_buffer buffer;
+ int status, ret, whitelisted;
+ const char *product;
+
+@@ -698,9 +706,9 @@ static int __init dell_setup_rfkill(void
+ if (!force_rfkill && !whitelisted)
+ return 0;
+
+- dell_set_arguments(0, 0, 0, 0);
+- ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
+- status = buffer->output[1];
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_INFO, SELECT_RFKILL);
++ status = buffer.output[1];
+
+ /* dell wireless info smbios call is not supported */
+ if (ret != 0)
+@@ -853,6 +861,7 @@ static void dell_cleanup_rfkill(void)
+
+ static int dell_send_intensity(struct backlight_device *bd)
+ {
++ struct calling_interface_buffer buffer;
+ struct calling_interface_token *token;
+ int ret;
+
+@@ -860,17 +869,21 @@ static int dell_send_intensity(struct ba
+ if (!token)
+ return -ENODEV;
+
+- dell_set_arguments(token->location, bd->props.brightness, 0, 0);
++ dell_fill_request(&buffer,
++ token->location, bd->props.brightness, 0, 0);
+ if (power_supply_is_system_supplied() > 0)
+- ret = dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_AC);
++ ret = dell_send_request(&buffer,
++ CLASS_TOKEN_WRITE, SELECT_TOKEN_AC);
+ else
+- ret = dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_BAT);
++ ret = dell_send_request(&buffer,
++ CLASS_TOKEN_WRITE, SELECT_TOKEN_BAT);
+
+ return ret;
+ }
+
+ static int dell_get_intensity(struct backlight_device *bd)
+ {
++ struct calling_interface_buffer buffer;
+ struct calling_interface_token *token;
+ int ret;
+
+@@ -878,14 +891,17 @@ static int dell_get_intensity(struct bac
+ if (!token)
+ return -ENODEV;
+
+- dell_set_arguments(token->location, 0, 0, 0);
++ dell_fill_request(&buffer, token->location, 0, 0, 0);
+ if (power_supply_is_system_supplied() > 0)
+- ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_AC);
++ ret = dell_send_request(&buffer,
++ CLASS_TOKEN_READ, SELECT_TOKEN_AC);
+ else
+- ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_BAT);
++ ret = dell_send_request(&buffer,
++ CLASS_TOKEN_READ, SELECT_TOKEN_BAT);
+
+ if (ret == 0)
+- ret = buffer->output[1];
++ ret = buffer.output[1];
++
+ return ret;
+ }
+
+@@ -1149,31 +1165,33 @@ static DEFINE_MUTEX(kbd_led_mutex);
+
+ static int kbd_get_info(struct kbd_info *info)
+ {
++ struct calling_interface_buffer buffer;
+ u8 units;
+ int ret;
+
+- dell_set_arguments(0, 0, 0, 0);
+- ret = dell_send_request(CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer,
++ CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
+ if (ret)
+ return ret;
+
+- info->modes = buffer->output[1] & 0xFFFF;
+- info->type = (buffer->output[1] >> 24) & 0xFF;
+- info->triggers = buffer->output[2] & 0xFF;
+- units = (buffer->output[2] >> 8) & 0xFF;
+- info->levels = (buffer->output[2] >> 16) & 0xFF;
++ info->modes = buffer.output[1] & 0xFFFF;
++ info->type = (buffer.output[1] >> 24) & 0xFF;
++ info->triggers = buffer.output[2] & 0xFF;
++ units = (buffer.output[2] >> 8) & 0xFF;
++ info->levels = (buffer.output[2] >> 16) & 0xFF;
+
+ if (quirks && quirks->kbd_led_levels_off_1 && info->levels)
+ info->levels--;
+
+ if (units & BIT(0))
+- info->seconds = (buffer->output[3] >> 0) & 0xFF;
++ info->seconds = (buffer.output[3] >> 0) & 0xFF;
+ if (units & BIT(1))
+- info->minutes = (buffer->output[3] >> 8) & 0xFF;
++ info->minutes = (buffer.output[3] >> 8) & 0xFF;
+ if (units & BIT(2))
+- info->hours = (buffer->output[3] >> 16) & 0xFF;
++ info->hours = (buffer.output[3] >> 16) & 0xFF;
+ if (units & BIT(3))
+- info->days = (buffer->output[3] >> 24) & 0xFF;
++ info->days = (buffer.output[3] >> 24) & 0xFF;
+
+ return ret;
+ }
+@@ -1233,31 +1251,34 @@ static int kbd_set_level(struct kbd_stat
+
+ static int kbd_get_state(struct kbd_state *state)
+ {
++ struct calling_interface_buffer buffer;
+ int ret;
+
+- dell_set_arguments(0x1, 0, 0, 0);
+- ret = dell_send_request(CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
++ dell_fill_request(&buffer, 0, 0, 0, 0);
++ ret = dell_send_request(&buffer,
++ CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
+ if (ret)
+ return ret;
+
+- state->mode_bit = ffs(buffer->output[1] & 0xFFFF);
++ state->mode_bit = ffs(buffer.output[1] & 0xFFFF);
+ if (state->mode_bit != 0)
+ state->mode_bit--;
+
+- state->triggers = (buffer->output[1] >> 16) & 0xFF;
+- state->timeout_value = (buffer->output[1] >> 24) & 0x3F;
+- state->timeout_unit = (buffer->output[1] >> 30) & 0x3;
+- state->als_setting = buffer->output[2] & 0xFF;
+- state->als_value = (buffer->output[2] >> 8) & 0xFF;
+- state->level = (buffer->output[2] >> 16) & 0xFF;
+- state->timeout_value_ac = (buffer->output[2] >> 24) & 0x3F;
+- state->timeout_unit_ac = (buffer->output[2] >> 30) & 0x3;
++ state->triggers = (buffer.output[1] >> 16) & 0xFF;
++ state->timeout_value = (buffer.output[1] >> 24) & 0x3F;
++ state->timeout_unit = (buffer.output[1] >> 30) & 0x3;
++ state->als_setting = buffer.output[2] & 0xFF;
++ state->als_value = (buffer.output[2] >> 8) & 0xFF;
++ state->level = (buffer.output[2] >> 16) & 0xFF;
++ state->timeout_value_ac = (buffer.output[2] >> 24) & 0x3F;
++ state->timeout_unit_ac = (buffer.output[2] >> 30) & 0x3;
+
+ return ret;
+ }
+
+ static int kbd_set_state(struct kbd_state *state)
+ {
++ struct calling_interface_buffer buffer;
+ int ret;
+ u32 input1;
+ u32 input2;
+@@ -1270,8 +1291,9 @@ static int kbd_set_state(struct kbd_stat
+ input2 |= (state->level & 0xFF) << 16;
+ input2 |= (state->timeout_value_ac & 0x3F) << 24;
+ input2 |= (state->timeout_unit_ac & 0x3) << 30;
+- dell_set_arguments(0x2, input1, input2, 0);
+- ret = dell_send_request(CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
++ dell_fill_request(&buffer, 0x2, input1, input2, 0);
++ ret = dell_send_request(&buffer,
++ CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
+
+ return ret;
+ }
+@@ -1298,6 +1320,7 @@ static int kbd_set_state_safe(struct kbd
+
+ static int kbd_set_token_bit(u8 bit)
+ {
++ struct calling_interface_buffer buffer;
+ struct calling_interface_token *token;
+ int ret;
+
+@@ -1308,14 +1331,15 @@ static int kbd_set_token_bit(u8 bit)
+ if (!token)
+ return -EINVAL;
+
+- dell_set_arguments(token->location, token->value, 0, 0);
+- ret = dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
++ dell_fill_request(&buffer, token->location, token->value, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
+
+ return ret;
+ }
+
+ static int kbd_get_token_bit(u8 bit)
+ {
++ struct calling_interface_buffer buffer;
+ struct calling_interface_token *token;
+ int ret;
+ int val;
+@@ -1327,9 +1351,9 @@ static int kbd_get_token_bit(u8 bit)
+ if (!token)
+ return -EINVAL;
+
+- dell_set_arguments(token->location, 0, 0, 0);
+- ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_STD);
+- val = buffer->output[1];
++ dell_fill_request(&buffer, token->location, 0, 0, 0);
++ ret = dell_send_request(&buffer, CLASS_TOKEN_READ, SELECT_TOKEN_STD);
++ val = buffer.output[1];
+
+ if (ret)
+ return ret;
+@@ -2046,6 +2070,7 @@ static struct notifier_block dell_laptop
+
+ int dell_micmute_led_set(int state)
+ {
++ struct calling_interface_buffer buffer;
+ struct calling_interface_token *token;
+
+ if (state == 0)
+@@ -2058,8 +2083,8 @@ int dell_micmute_led_set(int state)
+ if (!token)
+ return -ENODEV;
+
+- dell_set_arguments(token->location, token->value, 0, 0);
+- dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
++ dell_fill_request(&buffer, token->location, token->value, 0, 0);
++ dell_send_request(&buffer, CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
+
+ return state;
+ }
+@@ -2090,13 +2115,6 @@ static int __init dell_init(void)
+ if (ret)
+ goto fail_platform_device2;
+
+- buffer = kzalloc(sizeof(struct calling_interface_buffer), GFP_KERNEL);
+- if (!buffer) {
+- ret = -ENOMEM;
+- goto fail_buffer;
+- }
+-
+-
+ ret = dell_setup_rfkill();
+
+ if (ret) {
+@@ -2121,10 +2139,13 @@ static int __init dell_init(void)
+
+ token = dell_smbios_find_token(BRIGHTNESS_TOKEN);
+ if (token) {
+- dell_set_arguments(token->location, 0, 0, 0);
+- ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_AC);
++ struct calling_interface_buffer buffer;
++
++ dell_fill_request(&buffer, token->location, 0, 0, 0);
++ ret = dell_send_request(&buffer,
++ CLASS_TOKEN_READ, SELECT_TOKEN_AC);
+ if (ret)
+- max_intensity = buffer->output[3];
++ max_intensity = buffer.output[3];
+ }
+
+ if (max_intensity) {
+@@ -2158,8 +2179,6 @@ static int __init dell_init(void)
+ fail_get_brightness:
+ backlight_device_unregister(dell_backlight_device);
+ fail_backlight:
+- kfree(buffer);
+-fail_buffer:
+ dell_cleanup_rfkill();
+ fail_rfkill:
+ platform_device_del(platform_device);
+@@ -2179,7 +2198,6 @@ static void __exit dell_exit(void)
+ touchpad_led_exit();
+ kbd_led_exit();
+ backlight_device_unregister(dell_backlight_device);
+- kfree(buffer);
+ dell_cleanup_rfkill();
+ if (platform_device) {
+ platform_device_unregister(platform_device);