diff options
| -rw-r--r-- | drivers/iio/industrialio-core.c | 98 | ||||
| -rw-r--r-- | include/linux/iio/iio.h | 3 |
2 files changed, 66 insertions, 35 deletions
diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 3dccd6c3a889..8848f16c547b 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -408,6 +408,64 @@ static ssize_t iio_read_channel_info(struct device *dev, } } +/** + * 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, @@ -415,8 +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) @@ -435,39 +493,9 @@ static ssize_t iio_write_channel_info(struct device *dev, return -EINVAL; } - if (buf[0] == '-') { - negative = true; - buf++; - } else if (buf[0] == '+') { - buf++; - } - - while (*buf) { - if ('0' <= *buf && *buf <= '9') { - if (integer_part) - integer = integer*10 + *buf - '0'; - else { - fract += fract_mult*(*buf - '0'); - fract_mult /= 10; - } - } else if (*buf == '\n') { - if (*(buf + 1) == '\0') - break; - else - return -EINVAL; - } else if (*buf == '.' && integer_part) { - 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); diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index adca93a999a7..da8c776ba0bd 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -620,6 +620,9 @@ static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev) }; #endif +int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer, + int *fract); + /** * IIO_DEGREE_TO_RAD() - Convert degree to rad * @deg: A value in degree |