diff options
| author | Javier Martinez Canillas <javierm@redhat.com> | 2023-01-21 20:09:30 +0100 |
|---|---|---|
| committer | Javier Martinez Canillas <javierm@redhat.com> | 2023-01-24 11:02:33 +0100 |
| commit | 51affef35bb39f186aef7eeeb4a7f9ceccd3e65e (patch) | |
| tree | c660a0135ddede55cd2bdbef28376996203da3d5 | |
| parent | 998101f2a78cf506022f2094461105cb3d00e19f (diff) | |
drm/ssd130x: Silence a `dubious: x & !y` warningdrm-misc-next-2023-01-24
The sparse tool complains with the following warning:
$ make M=drivers/gpu/drm/solomon/ C=2
CC [M] drivers/gpu/drm/solomon/ssd130x.o
CHECK drivers/gpu/drm/solomon/ssd130x.c
drivers/gpu/drm/solomon/ssd130x.c:363:21: warning: dubious: x & !y
This seems to be a false positive in my opinion but still we can silence
the tool while making the code easier to read. Let's also add a comment,
to explain why the "com_seq" logical not is used rather than its value.
Reported-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Reviewed-by: Thomas Zimmermann <tzimmermann@suse.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20230121190930.2804224-1-javierm@redhat.com
| -rw-r--r-- | drivers/gpu/drm/solomon/ssd130x.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/gpu/drm/solomon/ssd130x.c b/drivers/gpu/drm/solomon/ssd130x.c index c3bf3a18302e..b16330a8b624 100644 --- a/drivers/gpu/drm/solomon/ssd130x.c +++ b/drivers/gpu/drm/solomon/ssd130x.c @@ -81,7 +81,7 @@ #define SSD130X_SET_PRECHARGE_PERIOD2_MASK GENMASK(7, 4) #define SSD130X_SET_PRECHARGE_PERIOD2_SET(val) FIELD_PREP(SSD130X_SET_PRECHARGE_PERIOD2_MASK, (val)) #define SSD130X_SET_COM_PINS_CONFIG1_MASK GENMASK(4, 4) -#define SSD130X_SET_COM_PINS_CONFIG1_SET(val) FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG1_MASK, !(val)) +#define SSD130X_SET_COM_PINS_CONFIG1_SET(val) FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG1_MASK, (val)) #define SSD130X_SET_COM_PINS_CONFIG2_MASK GENMASK(5, 5) #define SSD130X_SET_COM_PINS_CONFIG2_SET(val) FIELD_PREP(SSD130X_SET_COM_PINS_CONFIG2_MASK, (val)) @@ -298,6 +298,7 @@ static void ssd130x_power_off(struct ssd130x_device *ssd130x) static int ssd130x_init(struct ssd130x_device *ssd130x) { u32 precharge, dclk, com_invdir, compins, chargepump, seg_remap; + bool scan_mode; int ret; /* Set initial contrast */ @@ -360,7 +361,13 @@ static int ssd130x_init(struct ssd130x_device *ssd130x) /* Set COM pins configuration */ compins = BIT(1); - compins |= (SSD130X_SET_COM_PINS_CONFIG1_SET(ssd130x->com_seq) | + /* + * The COM scan mode field values are the inverse of the boolean DT + * property "solomon,com-seq". The value 0b means scan from COM0 to + * COM[N - 1] while 1b means scan from COM[N - 1] to COM0. + */ + scan_mode = !ssd130x->com_seq; + compins |= (SSD130X_SET_COM_PINS_CONFIG1_SET(scan_mode) | SSD130X_SET_COM_PINS_CONFIG2_SET(ssd130x->com_lrremap)); ret = ssd130x_write_cmd(ssd130x, 2, SSD130X_SET_COM_PINS_CONFIG, compins); if (ret < 0) |