dell-laptop: Check return value of each SMBIOS call

Make sure that return value of each SMBIOS call is properly checked and do
not continue processing output if the call failed.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Darren Hart <dvhart@linux.intel.com>

diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index 85fbe7c..efcfc49 100644 (file)
--- a/drivers/platform/x86/dell-laptop.c
+++ b/drivers/platform/x86/dell-laptop.c
@@ -553,9 +553,15 @@ static int dell_rfkill_set(void *data, bool blocked)
        int disable = blocked ? 1 : 0;
        unsigned long radio = (unsigned long)data;
        int hwswitch_bit = (unsigned long)data - 1;
+       int ret;
 
        get_buffer();
+
        dell_send_request(buffer, 17, 11);
+       ret = buffer->output[0];
+
+       if (ret != 0)
+               goto out;
 
        /* If the hardware switch controls this radio, and the hardware
           switch is disabled, always disable the radio */
@@ -567,9 +573,11 @@ static int dell_rfkill_set(void *data, bool blocked)
 
        buffer->input[0] = (1 | (radio<<8) | (disable << 16));
        dell_send_request(buffer, 17, 11);
+       ret = buffer->output[0];
 
+ out:
        release_buffer();
-       return 0;
+       return dell_smi_error(ret);
 }
 
 /* Must be called with the buffer held */
@@ -598,14 +606,18 @@ static void dell_rfkill_update_hw_state(struct rfkill *rfkill, int radio,
 static void dell_rfkill_query(struct rfkill *rfkill, void *data)
 {
        int status;
+       int ret;
 
        get_buffer();
        dell_send_request(buffer, 17, 11);
+       ret = buffer->output[0];
        status = buffer->output[1];
+       release_buffer();
 
-       dell_rfkill_update_hw_state(rfkill, (unsigned long)data, status);
+       if (ret != 0)
+               return;
 
-       release_buffer();
+       dell_rfkill_update_hw_state(rfkill, (unsigned long)data, status);
 }
 
 static const struct rfkill_ops dell_rfkill_ops = {
@@ -618,12 +630,15 @@ static struct dentry *dell_laptop_dir;
 static int dell_debugfs_show(struct seq_file *s, void *data)
 {
        int status;
+       int ret;
 
        get_buffer();
        dell_send_request(buffer, 17, 11);
+       ret = buffer->output[0];
        status = buffer->output[1];
        release_buffer();
 
+       seq_printf(s, "return:\t%d\n", ret);
        seq_printf(s, "status:\t0x%X\n", status);
        seq_printf(s, "Bit 0 : Hardware switch supported:   %lu\n",
                   status & BIT(0));
@@ -702,11 +717,17 @@ static const struct file_operations dell_debugfs_fops = {
 static void dell_update_rfkill(struct work_struct *ignored)
 {
        int status;
+       int ret;
 
        get_buffer();
+
        dell_send_request(buffer, 17, 11);
+       ret = buffer->output[0];
        status = buffer->output[1];
 
+       if (ret != 0)
+               goto out;
+
        if (wifi_rfkill) {
                dell_rfkill_update_hw_state(wifi_rfkill, 1, status);
                dell_rfkill_update_sw_state(wifi_rfkill, 1, status);
@@ -720,6 +741,7 @@ static void dell_update_rfkill(struct work_struct *ignored)
                dell_rfkill_update_sw_state(wwan_rfkill, 3, status);
        }
 
+ out:
        release_buffer();
 }
 static DECLARE_DELAYED_WORK(dell_rfkill_work, dell_update_rfkill);
@@ -781,6 +803,7 @@ static int __init dell_setup_rfkill(void)
 
        get_buffer();
        dell_send_request(buffer, 17, 11);
+       ret = buffer->output[0];
        status = buffer->output[1];
        clear_buffer();
        buffer->input[0] = 0x2;
@@ -788,6 +811,10 @@ static int __init dell_setup_rfkill(void)
        hwswitch_state = buffer->output[1];
        release_buffer();
 
+       /* dell wireless info smbios call is not supported */
+       if (ret != 0)
+               return 0;
+
        if (!(status & BIT(0))) {
                if (force_rfkill) {
                        /* No hwsitch, clear all hw-controlled bits */
@@ -941,47 +968,50 @@ static void dell_cleanup_rfkill(void)
 
 static int dell_send_intensity(struct backlight_device *bd)
 {
-       int ret = 0;
+       int token;
+       int ret;
+
+       token = find_token_location(BRIGHTNESS_TOKEN);
+       if (token == -1)
+               return -ENODEV;
 
        get_buffer();
-       buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
+       buffer->input[0] = token;
        buffer->input[1] = bd->props.brightness;
 
-       if (buffer->input[0] == -1) {
-               ret = -ENODEV;
-               goto out;
-       }
-
        if (power_supply_is_system_supplied() > 0)
                dell_send_request(buffer, 1, 2);
        else
                dell_send_request(buffer, 1, 1);
 
- out:
+       ret = dell_smi_error(buffer->output[0]);
+
        release_buffer();
        return ret;
 }
 
 static int dell_get_intensity(struct backlight_device *bd)
 {
-       int ret = 0;
+       int token;
+       int ret;
 
-       get_buffer();
-       buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
+       token = find_token_location(BRIGHTNESS_TOKEN);
+       if (token == -1)
+               return -ENODEV;
 
-       if (buffer->input[0] == -1) {
-               ret = -ENODEV;
-               goto out;
-       }
+       get_buffer();
+       buffer->input[0] = token;
 
        if (power_supply_is_system_supplied() > 0)
                dell_send_request(buffer, 0, 2);
        else
                dell_send_request(buffer, 0, 1);
 
-       ret = buffer->output[1];
+       if (buffer->output[0])
+               ret = dell_smi_error(buffer->output[0]);
+       else
+               ret = buffer->output[1];
 
- out:
        release_buffer();
        return ret;
 }
@@ -2045,6 +2075,7 @@ static void kbd_led_exit(void)
 static int __init dell_init(void)
 {
        int max_intensity = 0;
+       int token;
        int ret;
 
        if (!dmi_check_system(dell_device_table))
@@ -2103,13 +2134,15 @@ static int __init dell_init(void)
        if (acpi_video_get_backlight_type() != acpi_backlight_vendor)
                return 0;
 
-       get_buffer();
-       buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
-       if (buffer->input[0] != -1) {
+       token = find_token_location(BRIGHTNESS_TOKEN);
+       if (token != -1) {
+               get_buffer();
+               buffer->input[0] = token;
                dell_send_request(buffer, 0, 2);
-               max_intensity = buffer->output[3];
+               if (buffer->output[0] == 0)
+                       max_intensity = buffer->output[3];
+               release_buffer();
        }
-       release_buffer();
 
        if (max_intensity) {
                struct backlight_properties props;