[PATCH v3 2/2] auxdisplay: charlcd: Deduplicate simple_strtoul()

Andy Shevchenko
2019-07-04T11:55:42Z

Like in the commit
8b2303de399f ("serial: core: Fix handling of options after MMIO address")
we may use simple_strtoul() which in comparison to kstrtoul() can do conversion
in-place without additional and unnecessary code to be written.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
- no change since v2
drivers/auxdisplay/charlcd.c | 34 +++++++---------------------------
1 file changed, 7 insertions(+), 27 deletions(-)

diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c
index 92745efefb54..3858dc7a4154 100644
--- a/drivers/auxdisplay/charlcd.c
+++ b/drivers/auxdisplay/charlcd.c
@@ -287,31 +287,6 @@ static int charlcd_init_display(struct charlcd *lcd)
return 0;
}

-/*
- * Parses an unsigned integer from a string, until a non-digit character
- * is found. The empty string is not accepted. No overflow checks are done.
- *
- * Returns whether the parsing was successful. Only in that case
- * the output parameters are written to.
- *
- * TODO: If the kernel adds an inplace version of kstrtoul(), this function
- * could be easily replaced by that.
- */
-static bool parse_n(const char *s, unsigned long *res, const char **next_s)
-{
- if (!isdigit(*s))
- return false;
-
- *res = 0;
- while (isdigit(*s)) {
- *res = *res * 10 + (*s - '0');
- ++s;
- }
-
- *next_s = s;
- return true;
-}
-
/*
* Parses a movement command of the form "(.*);", where the group can be
* any number of subcommands of the form "(x|y)[0-9]+".
@@ -336,6 +311,7 @@ static bool parse_xy(const char *s, unsigned long *x, unsigned long *y)
{
unsigned long new_x = *x;
unsigned long new_y = *y;
+ char *p;

for (;;) {
if (!*s)
@@ -345,11 +321,15 @@ static bool parse_xy(const char *s, unsigned long *x, unsigned long *y)
break;

if (*s == 'x') {
- if (!parse_n(s + 1, &new_x, &s))
+ new_x = simple_strtoul(s + 1, &p, 10);
+ if (p == s + 1)
return false;
+ s = p;
} else if (*s == 'y') {
- if (!parse_n(s + 1, &new_y, &s))
+ new_y = simple_strtoul(s + 1, &p, 10);
+ if (p == s + 1)
return false;
+ s = p;
} else {
return false;
}
--
2.20.1