[PATCH] platform/x86: dell-laptop: Guard SMBIOS calls with a mutex
From: Mario Limonciello
Date: Mon Jan 29 2018 - 18:16:22 EST
Suggested-by: Pali Rohar <pali.rohar@xxxxxxxxx>
Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxxx>
---
drivers/platform/x86/dell-laptop.c | 67 ++++++++++++++++++++++++++++++--------
1 file changed, 53 insertions(+), 14 deletions(-)
diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index fc2dfc8..f8e2bd8 100644
--- a/drivers/platform/x86/dell-laptop.c
+++ b/drivers/platform/x86/dell-laptop.c
@@ -85,6 +85,7 @@ static struct rfkill *wifi_rfkill;
static struct rfkill *bluetooth_rfkill;
static struct rfkill *wwan_rfkill;
static bool force_rfkill;
+static DEFINE_MUTEX(buffer_mutex);
module_param(force_rfkill, bool, 0444);
MODULE_PARM_DESC(force_rfkill, "enable rfkill on non whitelisted models");
@@ -472,16 +473,17 @@ static int dell_rfkill_set(void *data, bool blocked)
int status;
int ret;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0, 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
if (ret)
- return ret;
+ goto out;
status = buffer->output[1];
dell_set_arguments(0x2, 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
if (ret)
- return ret;
+ goto out;
hwswitch = buffer->output[1];
/* If the hardware switch controls this radio, and the hardware
@@ -492,6 +494,9 @@ static int dell_rfkill_set(void *data, bool blocked)
dell_set_arguments(1 | (radio<<8) | (disable << 16), 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
+
+out:
+ mutex_unlock(&buffer_mutex);
return ret;
}
@@ -501,8 +506,10 @@ static void dell_rfkill_update_sw_state(struct rfkill *rfkill, int radio,
if (status & BIT(0)) {
/* Has hw-switch, sync sw_state to BIOS */
int block = rfkill_blocked(rfkill);
+ mutex_lock(&buffer_mutex);
dell_set_arguments(1 | (radio << 8) | (block << 16), 0, 0, 0);
dell_send_request(CLASS_INFO, SELECT_RFKILL);
+ mutex_unlock(&buffer_mutex);
} else {
/* No hw-switch, sync BIOS state to sw_state */
rfkill_set_sw_state(rfkill, !!(status & BIT(radio + 16)));
@@ -523,22 +530,24 @@ static void dell_rfkill_query(struct rfkill *rfkill, void *data)
int status;
int ret;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0, 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
status = buffer->output[1];
- if (ret != 0 || !(status & BIT(0))) {
- return;
- }
+ if (ret != 0 || !(status & BIT(0)))
+ goto out;
dell_set_arguments(0, 0x2, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
hwswitch = buffer->output[1];
if (ret != 0)
- return;
+ goto out;
dell_rfkill_update_hw_state(rfkill, radio, status, hwswitch);
+out:
+ mutex_unlock(&buffer_mutex);
}
static const struct rfkill_ops dell_rfkill_ops = {
@@ -555,16 +564,19 @@ static int dell_debugfs_show(struct seq_file *s, void *data)
int status;
int ret;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0, 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
if (ret)
- return ret;
+ goto out;
status = buffer->output[1];
dell_set_arguments(0, 0x2, 0, 0);
hwswitch_ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
- if (hwswitch_ret)
- return hwswitch_ret;
+ if (hwswitch_ret) {
+ ret = hwswitch_ret;
+ goto out;
+ }
hwswitch_state = buffer->output[1];
seq_printf(s, "return:\t%d\n", ret);
@@ -628,7 +640,9 @@ static int dell_debugfs_show(struct seq_file *s, void *data)
seq_printf(s, "Bit 15: Wifi locator setting locked: %lu\n",
(hwswitch_state & BIT(15)) >> 15);
- return 0;
+out:
+ mutex_unlock(&buffer_mutex);
+ return ret;
}
static int dell_debugfs_open(struct inode *inode, struct file *file)
@@ -650,12 +664,13 @@ static void dell_update_rfkill(struct work_struct *ignored)
int status;
int ret;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0, 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
status = buffer->output[1];
if (ret != 0)
- return;
+ goto out;
dell_set_arguments(0, 0x2, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
@@ -676,6 +691,8 @@ static void dell_update_rfkill(struct work_struct *ignored)
dell_rfkill_update_hw_state(wwan_rfkill, 3, status, hwswitch);
dell_rfkill_update_sw_state(wwan_rfkill, 3, status);
}
+out:
+ mutex_unlock(&buffer_mutex);
}
static DECLARE_DELAYED_WORK(dell_rfkill_work, dell_update_rfkill);
@@ -734,9 +751,11 @@ static int __init dell_setup_rfkill(void)
if (!force_rfkill && !whitelisted)
return 0;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0, 0, 0, 0);
ret = dell_send_request(CLASS_INFO, SELECT_RFKILL);
status = buffer->output[1];
+ mutex_unlock(&buffer_mutex);
/* dell wireless info smbios call is not supported */
if (ret != 0)
@@ -896,11 +915,13 @@ static int dell_send_intensity(struct backlight_device *bd)
if (!token)
return -ENODEV;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(token->location, bd->props.brightness, 0, 0);
if (power_supply_is_system_supplied() > 0)
ret = dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_AC);
else
ret = dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_BAT);
+ mutex_unlock(&buffer_mutex);
return ret;
}
@@ -914,6 +935,7 @@ static int dell_get_intensity(struct backlight_device *bd)
if (!token)
return -ENODEV;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(token->location, 0, 0, 0);
if (power_supply_is_system_supplied() > 0)
ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_AC);
@@ -922,6 +944,8 @@ static int dell_get_intensity(struct backlight_device *bd)
if (ret == 0)
ret = buffer->output[1];
+ mutex_unlock(&buffer_mutex);
+
return ret;
}
@@ -1189,10 +1213,11 @@ static int kbd_get_info(struct kbd_info *info)
u8 units;
int ret;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0, 0, 0, 0);
ret = dell_send_request(CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
if (ret)
- return ret;
+ goto out;
info->modes = buffer->output[1] & 0xFFFF;
info->type = (buffer->output[1] >> 24) & 0xFF;
@@ -1212,6 +1237,8 @@ static int kbd_get_info(struct kbd_info *info)
if (units & BIT(3))
info->days = (buffer->output[3] >> 24) & 0xFF;
+out:
+ mutex_unlock(&buffer_mutex);
return ret;
}
@@ -1272,10 +1299,11 @@ static int kbd_get_state(struct kbd_state *state)
{
int ret;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0x1, 0, 0, 0);
ret = dell_send_request(CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
if (ret)
- return ret;
+ goto out;
state->mode_bit = ffs(buffer->output[1] & 0xFFFF);
if (state->mode_bit != 0)
@@ -1289,7 +1317,8 @@ static int kbd_get_state(struct kbd_state *state)
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;
-
+out:
+ mutex_unlock(&buffer_mutex);
return ret;
}
@@ -1307,8 +1336,10 @@ static int kbd_set_state(struct kbd_state *state)
input2 |= (state->level & 0xFF) << 16;
input2 |= (state->timeout_value_ac & 0x3F) << 24;
input2 |= (state->timeout_unit_ac & 0x3) << 30;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(0x2, input1, input2, 0);
ret = dell_send_request(CLASS_KBD_BACKLIGHT, SELECT_KBD_BACKLIGHT);
+ mutex_unlock(&buffer_mutex);
return ret;
}
@@ -1345,8 +1376,10 @@ static int kbd_set_token_bit(u8 bit)
if (!token)
return -EINVAL;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(token->location, token->value, 0, 0);
ret = dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
+ mutex_unlock(&buffer_mutex);
return ret;
}
@@ -1364,9 +1397,11 @@ static int kbd_get_token_bit(u8 bit)
if (!token)
return -EINVAL;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(token->location, 0, 0, 0);
ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_STD);
val = buffer->output[1];
+ mutex_unlock(&buffer_mutex);
if (ret)
return ret;
@@ -2114,8 +2149,10 @@ int dell_micmute_led_set(int state)
if (!token)
return -ENODEV;
+ mutex_lock(&buffer_mutex);
dell_set_arguments(token->location, token->value, 0, 0);
dell_send_request(CLASS_TOKEN_WRITE, SELECT_TOKEN_STD);
+ mutex_unlock(&buffer_mutex);
return state;
}
@@ -2177,10 +2214,12 @@ static int __init dell_init(void)
token = dell_smbios_find_token(BRIGHTNESS_TOKEN);
if (token) {
+ mutex_lock(&buffer_mutex);
dell_set_arguments(token->location, 0, 0, 0);
ret = dell_send_request(CLASS_TOKEN_READ, SELECT_TOKEN_AC);
if (ret)
max_intensity = buffer->output[3];
+ mutex_unlock(&buffer_mutex);
}
if (max_intensity) {
--
2.7.4