iio:light:stk3310: add more error handling

Check for the following error cases:
  * lower boundary for val in _write_event
  * return value of regmap_(field_)read
  * possible values for chan->type
  * return value of stk3310_gpio_probe

Also add an error path in _probe to put the sensor back into stand-by mode
in case of serious errors.

Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

1 files changed, 45 insertions, 14 deletions

diff --git a/drivers/iio/light/stk3310.c b/drivers/iio/light/stk3310.c
index f101bb5bddc7..09f2f6a30b79 100644
--- a/drivers/iio/light/stk3310.c
+++ b/drivers/iio/light/stk3310.c
@@ -241,8 +241,11 @@ static int stk3310_write_event(struct iio_dev *indio_dev,
         struct stk3310_data *data = iio_priv(indio_dev);
         struct i2c_client *client = data->client;
 
-        regmap_field_read(data->reg_ps_gain, &index);
-        if (val > stk3310_ps_max[index])
+        ret = regmap_field_read(data->reg_ps_gain, &index);
+        if (ret < 0)
+                return ret;
+
+        if (val < 0 || val > stk3310_ps_max[index])
                 return -EINVAL;
 
         if (dir == IIO_EV_DIR_RISING)
@@ -266,9 +269,12 @@ static int stk3310_read_event_config(struct iio_dev *indio_dev,
                                      enum iio_event_direction dir)
 {
         unsigned int event_val;
+        int ret;
         struct stk3310_data *data = iio_priv(indio_dev);
 
-        regmap_field_read(data->reg_int_ps, &event_val);
+        ret = regmap_field_read(data->reg_int_ps, &event_val);
+        if (ret < 0)
+                return ret;
 
         return event_val;
 }
@@ -307,14 +313,16 @@ static int stk3310_read_raw(struct iio_dev *indio_dev,
         struct stk3310_data *data = iio_priv(indio_dev);
         struct i2c_client *client = data->client;
 
+        if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY)
+                return -EINVAL;
+
         switch (mask) {
         case IIO_CHAN_INFO_RAW:
                 if (chan->type == IIO_LIGHT)
                         reg = STK3310_REG_ALS_DATA_MSB;
-                else if (chan->type == IIO_PROXIMITY)
-                        reg = STK3310_REG_PS_DATA_MSB;
                 else
-                        return -EINVAL;
+                        reg = STK3310_REG_PS_DATA_MSB;
+
                 mutex_lock(&data->lock);
                 ret = regmap_bulk_read(data->regmap, reg, &buf, 2);
                 if (ret < 0) {
@@ -327,17 +335,23 @@ static int stk3310_read_raw(struct iio_dev *indio_dev,
                 return IIO_VAL_INT;
         case IIO_CHAN_INFO_INT_TIME:
                 if (chan->type == IIO_LIGHT)
-                        regmap_field_read(data->reg_als_it, &index);
+                        ret = regmap_field_read(data->reg_als_it, &index);
                 else
-                        regmap_field_read(data->reg_ps_it, &index);
+                        ret = regmap_field_read(data->reg_ps_it, &index);
+                if (ret < 0)
+                        return ret;
+
                 *val = stk3310_it_table[index][0];
                 *val2 = stk3310_it_table[index][1];
                 return IIO_VAL_INT_PLUS_MICRO;
         case IIO_CHAN_INFO_SCALE:
                 if (chan->type == IIO_LIGHT)
-                        regmap_field_read(data->reg_als_gain, &index);
+                        ret = regmap_field_read(data->reg_als_gain, &index);
                 else
-                        regmap_field_read(data->reg_ps_gain, &index);
+                        ret = regmap_field_read(data->reg_ps_gain, &index);
+                if (ret < 0)
+                        return ret;
+
                 *val = stk3310_scale_table[index][0];
                 *val2 = stk3310_scale_table[index][1];
                 return IIO_VAL_INT_PLUS_MICRO;
@@ -354,6 +368,9 @@ static int stk3310_write_raw(struct iio_dev *indio_dev,
         int index;
         struct stk3310_data *data = iio_priv(indio_dev);
 
+        if (chan->type != IIO_LIGHT && chan->type != IIO_PROXIMITY)
+                return -EINVAL;
+
         switch (mask) {
         case IIO_CHAN_INFO_INT_TIME:
                 index = stk3310_get_index(stk3310_it_table,
@@ -435,7 +452,10 @@ static int stk3310_init(struct iio_dev *indio_dev)
         struct stk3310_data *data = iio_priv(indio_dev);
         struct i2c_client *client = data->client;
 
-        regmap_read(data->regmap, STK3310_REG_ID, &chipid);
+        ret = regmap_read(data->regmap, STK3310_REG_ID, &chipid);
+        if (ret < 0)
+                return ret;
+
         if (chipid != STK3310_CHIP_ID_VAL &&
             chipid != STK3311_CHIP_ID_VAL) {
                 dev_err(&client->dev, "invalid chip id: 0x%x\n", chipid);
@@ -608,8 +628,13 @@ static int stk3310_probe(struct i2c_client *client,
         if (ret < 0)
                 return ret;
 
-        if (client->irq < 0)
+        if (client->irq < 0) {
                 client->irq = stk3310_gpio_probe(client);
+                if (client->irq < 0) {
+                        ret = client->irq;
+                        goto err_standby;
+                }
+        }
 
         if (client->irq >= 0) {
                 ret = devm_request_threaded_irq(&client->dev, client->irq,
@@ -618,17 +643,23 @@ static int stk3310_probe(struct i2c_client *client,
                                                 IRQF_TRIGGER_FALLING |
                                                 IRQF_ONESHOT,
                                                 STK3310_EVENT, indio_dev);
-                if (ret < 0)
+                if (ret < 0) {
                         dev_err(&client->dev, "request irq %d failed\n",
                                         client->irq);
+                        goto err_standby;
+                }
         }
 
         ret = iio_device_register(indio_dev);
         if (ret < 0) {
                 dev_err(&client->dev, "device_register failed\n");
-                stk3310_set_state(data, STK3310_STATE_STANDBY);
+                goto err_standby;
         }
 
+        return 0;
+
+err_standby:
+        stk3310_set_state(data, STK3310_STATE_STANDBY);
         return ret;
 }