Messages in this thread | | | From | Miguel Ojeda <> | Date | Sat, 10 Feb 2018 09:58:44 +0100 | Subject | Re: [PATCH 1/3] auxdisplay: charlcd: fix hex literal ranges for graphics command |
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On Sat, Feb 10, 2018 at 12:50 AM, Robert Abel <rabel@robertabel.eu> wrote: > The graphics command expects 16 hexadecimal literals, but would allow characters in range [0-9a-zA-Z] instead of [0-9a-fA-F]. > > Signed-off-by: Robert Abel <rabel@robertabel.eu> > --- > drivers/auxdisplay/charlcd.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/auxdisplay/charlcd.c b/drivers/auxdisplay/charlcd.c > index 642afd88870b..324d02f9f1c5 100644 > --- a/drivers/auxdisplay/charlcd.c > +++ b/drivers/auxdisplay/charlcd.c > @@ -441,9 +441,9 @@ static inline int handle_lcd_special_code(struct charlcd *lcd) > shift ^= 4; > if (*esc >= '0' && *esc <= '9') { > value |= (*esc - '0') << shift; > - } else if (*esc >= 'A' && *esc <= 'Z') { > + } else if (*esc >= 'A' && *esc <= 'F') { > value |= (*esc - 'A' + 10) << shift; > - } else if (*esc >= 'a' && *esc <= 'z') { > + } else if (*esc >= 'a' && *esc <= 'f') {
Willy, Geert: this seems obvious, but do you know if the broader range was intended for some reason? In that case, adding a comment to the code would be good. I found some related docs at Documentation/misc-devices/lcd-panel-cgram.txt by Willy (which, by the way, maybe now we should move them to Documentations/auxdisplay); but the paragraph does indeed say they have to be hex:
''' Some LCDs allow you to define up to 8 characters, mapped to ASCII characters 0 to 7. The escape code to define a new character is '\e[LG' followed by one digit from 0 to 7, representing the character number, and up to 8 couples of hex digits terminated by a semi-colon (';'). '''
> value |= (*esc - 'a' + 10) << shift; > } else { > esc++; > -- > 2.11.0 >
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