Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso...

[firefly-linux-kernel-4.4.55.git] / drivers / iio / industrialio-core.c

diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
index 6eb24dbc081ed2f158d9c46b4ccb5ee75ff20272..8848f16c547b07a44e2de1f1834283b8f88e8fb5 100644 (file)
--- a/drivers/iio/industrialio-core.c
+++ b/drivers/iio/industrialio-core.c
@@ -65,6 +65,7 @@ static const char * const iio_chan_type_name_spec[] = {
        [IIO_CAPACITANCE] = "capacitance",
        [IIO_ALTVOLTAGE] = "altvoltage",
        [IIO_CCT] = "cct",
+       [IIO_PRESSURE] = "pressure",
 };
 
 static const char * const iio_modifier_names[] = {
@@ -397,11 +398,74 @@ static ssize_t iio_read_channel_info(struct device *dev,
                val2 = do_div(tmp, 1000000000LL);
                val = tmp;
                return sprintf(buf, "%d.%09u\n", val, val2);
+       case IIO_VAL_FRACTIONAL_LOG2:
+               tmp = (s64)val * 1000000000LL >> val2;
+               val2 = do_div(tmp, 1000000000LL);
+               val = tmp;
+               return sprintf(buf, "%d.%09u\n", val, val2);
        default:
                return 0;
        }
 }
 
+/**
+ * iio_str_to_fixpoint() - Parse a fixed-point number from a string
+ * @str: The string to parse
+ * @fract_mult: Multiplier for the first decimal place, should be a power of 10
+ * @integer: The integer part of the number
+ * @fract: The fractional part of the number
+ *
+ * Returns 0 on success, or a negative error code if the string could not be
+ * parsed.
+ */
+int iio_str_to_fixpoint(const char *str, int fract_mult,
+       int *integer, int *fract)
+{
+       int i = 0, f = 0;
+       bool integer_part = true, negative = false;
+
+       if (str[0] == '-') {
+               negative = true;
+               str++;
+       } else if (str[0] == '+') {
+               str++;
+       }
+
+       while (*str) {
+               if ('0' <= *str && *str <= '9') {
+                       if (integer_part) {
+                               i = i * 10 + *str - '0';
+                       } else {
+                               f += fract_mult * (*str - '0');
+                               fract_mult /= 10;
+                       }
+               } else if (*str == '\n') {
+                       if (*(str + 1) == '\0')
+                               break;
+                       else
+                               return -EINVAL;
+               } else if (*str == '.' && integer_part) {
+                       integer_part = false;
+               } else {
+                       return -EINVAL;
+               }
+               str++;
+       }
+
+       if (negative) {
+               if (i)
+                       i = -i;
+               else
+                       f = -f;
+       }
+
+       *integer = i;
+       *fract = f;
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(iio_str_to_fixpoint);
+
 static ssize_t iio_write_channel_info(struct device *dev,
                                      struct device_attribute *attr,
                                      const char *buf,
@@ -409,8 +473,8 @@ static ssize_t iio_write_channel_info(struct device *dev,
 {
        struct iio_dev *indio_dev = dev_to_iio_dev(dev);
        struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-       int ret, integer = 0, fract = 0, fract_mult = 100000;
-       bool integer_part = true, negative = false;
+       int ret, fract_mult = 100000;
+       int integer, fract;
 
        /* Assumes decimal - precision based on number of digits */
        if (!indio_dev->info->write_raw)
@@ -429,39 +493,9 @@ static ssize_t iio_write_channel_info(struct device *dev,
                        return -EINVAL;
                }
 
-       if (buf[0] == '-') {
-               negative = true;
-               buf++;
-       }
-
-       while (*buf) {
-               if ('0' <= *buf && *buf <= '9') {
-                       if (integer_part)
-                               integer = integer*10 + *buf - '0';
-                       else {
-                               fract += fract_mult*(*buf - '0');
-                               if (fract_mult == 1)
-                                       break;
-                               fract_mult /= 10;
-                       }
-               } else if (*buf == '\n') {
-                       if (*(buf + 1) == '\0')
-                               break;
-                       else
-                               return -EINVAL;
-               } else if (*buf == '.') {
-                       integer_part = false;
-               } else {
-                       return -EINVAL;
-               }
-               buf++;
-       }
-       if (negative) {
-               if (integer)
-                       integer = -integer;
-               else
-                       fract = -fract;
-       }
+       ret = iio_str_to_fixpoint(buf, fract_mult, &integer, &fract);
+       if (ret)
+               return ret;
 
        ret = indio_dev->info->write_raw(indio_dev, this_attr->c,
                                         integer, fract, this_attr->address);
@@ -851,6 +885,7 @@ struct iio_dev *iio_device_alloc(int sizeof_priv)
                        return NULL;
                }
                dev_set_name(&dev->dev, "iio:device%d", dev->id);
+               INIT_LIST_HEAD(&dev->buffer_list);
        }
 
        return dev;