[PATCH 2/4] dell-laptop: Check return value of all SMBIOS calls

Pali Rohár
2015-06-21T08:40:48Z

Make sure that return value of all SMBIOS calls are properly checked and
do not continue of processing (received) information if call failed.

Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
---
drivers/platform/x86/dell-laptop.c | 61 +++++++++++++++++++++++++++++++-----
1 file changed, 54 insertions(+), 7 deletions(-)

diff --git a/drivers/platform/x86/dell-laptop.c b/drivers/platform/x86/dell-laptop.c
index ab89103..aaef335 100644
--- a/drivers/platform/x86/dell-laptop.c
+++ b/drivers/platform/x86/dell-laptop.c
@@ -548,21 +548,27 @@ 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 status;
+ int ret;

get_buffer();
dell_send_request(buffer, 17, 11);
+ ret = buffer->output[0];
+ status = buffer->output[1];

/* If the hardware switch controls this radio, and the hardware
switch is disabled, always disable the radio */
- if ((hwswitch_state & BIT(hwswitch_bit)) &&
- !(buffer->output[1] & BIT(16)))
+ if (ret == 0 &&
+ (hwswitch_state & BIT(hwswitch_bit)) &&
+ !(status & BIT(16)))
disable = 1;

buffer->input[0] = (1 | (radio<<8) | (disable << 16));
dell_send_request(buffer, 17, 11);
+ ret = buffer->output[0];

release_buffer();
- return 0;
+ return dell_smi_error(ret);
}

/* Must be called with the buffer held */
@@ -590,14 +596,18 @@ 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 = {
@@ -610,12 +620,15 @@ 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));
@@ -677,11 +690,16 @@ 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);
@@ -695,6 +713,7 @@ 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);
@@ -755,13 +774,35 @@ static int __init dell_setup_rfkill(void)
return 0;

get_buffer();
+
dell_send_request(buffer, 17, 11);
+ ret = buffer->output[0];
status = buffer->output[1];
+ if (ret != 0) {
+ /* dell wireless info smbios call is not working */
+ /* so there is no support for rfkill */
+ release_buffer();
+ return 0;
+ }
+
buffer->input[0] = 0x2;
dell_send_request(buffer, 17, 11);
+ ret = buffer->output[0];
hwswitch_state = buffer->output[1];
+
release_buffer();

+ if (ret != 0) {
+ /* dell wireless switch smbios call is not working */
+ if (force_rfkill) {
+ /* clear all hw-controlled bits */
+ hwswitch_state &= ~7;
+ } else {
+ /* rfkill is only tested on laptops with a hwswitch */
+ return 0;
+ }
+ }
+
if (!(status & BIT(0))) {
if (force_rfkill) {
/* No hwsitch, clear all hw-controlled bits */
@@ -931,6 +972,8 @@ static int dell_send_intensity(struct backlight_device *bd)
else
dell_send_request(buffer, 1, 1);

+ ret = dell_smi_error(buffer->output[0]);
+
out:
release_buffer();
return ret;
@@ -953,7 +996,10 @@ static int dell_get_intensity(struct backlight_device *bd)
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();
@@ -2087,7 +2133,8 @@ static int __init dell_init(void)
buffer->input[0] = find_token_location(BRIGHTNESS_TOKEN);
if (buffer->input[0] != -1) {
dell_send_request(buffer, 0, 2);
- max_intensity = buffer->output[3];
+ if (buffer->output[0] == 0)
+ max_intensity = buffer->output[3];
}
release_buffer();

--
1.7.9.5

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