[patch 18/86] auxdisplay: charlcd: deduplicate simple_strtoul()

Andrew Morton
2019-12-05T00:50:39Z

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Subject: auxdisplay: charlcd: deduplicate simple_strtoul()

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.

Link: http://lkml.kernel.org/r/20190801192904.41087-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Cc: Mans Rullgard <mans@mansr.com>
Cc: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

drivers/auxdisplay/charlcd.c | 34 ++++++---------------------------
1 file changed, 7 insertions(+), 27 deletions(-)

--- a/drivers/auxdisplay/charlcd.c~auxdisplay-charlcd-deduplicate-simple_strtoul
+++ a/drivers/auxdisplay/charlcd.c
@@ -288,31 +288,6 @@ static int charlcd_init_display(struct c
}

/*
- * 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, unsi
{
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, unsi
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;
}
_