[PATCH fbdev-for-next 2/2] video: ssd1307fb: Add support for the reset-active-low property

From: VokÃÄ Michal
Date: Fri Nov 02 2018 - 10:56:50 EST


The SSD130x OLEDÂdisplay reset signal is active low. Now the reset
sequence is implemented in such a way that DTS authors are forced to
define the reset-gpios property with GPIO_ACTIVE_HIGH to make the reset
work.

Add the reset-active-low property so the signal is inverted once again
and the GPIO_ACTIVE_LOW work as expected.

Signed-off-by: Michal VokÃÄ <michal.vokac@xxxxxxxxx>
---
drivers/video/fbdev/ssd1307fb.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
index e7ae135..790f1c4 100644
--- a/drivers/video/fbdev/ssd1307fb.c
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -608,6 +608,7 @@ static int ssd1307fb_probe(struct i2c_client *client,
struct fb_deferred_io *ssd1307fb_defio;
u32 vmem_size;
struct ssd1307fb_par *par;
+ bool reset_active_low;
u8 *vmem;
int ret;

@@ -671,6 +672,7 @@ static int ssd1307fb_probe(struct i2c_client *client,
par->com_seq = of_property_read_bool(node, "solomon,com-seq");
par->com_lrremap = of_property_read_bool(node, "solomon,com-lrremap");
par->com_invdir = of_property_read_bool(node, "solomon,com-invdir");
+ reset_active_low = of_property_read_bool(node, "reset-active-low");

par->contrast = 127;
par->vcomh = par->device_info->default_vcomh;
@@ -728,9 +730,9 @@ static int ssd1307fb_probe(struct i2c_client *client,

if (par->reset) {
/* Reset the screen */
- gpiod_set_value_cansleep(par->reset, 0);
+ gpiod_set_value_cansleep(par->reset, reset_active_low);
udelay(4);
- gpiod_set_value_cansleep(par->reset, 1);
+ gpiod_set_value_cansleep(par->reset, !reset_active_low);
udelay(4);
}

--
2.1.4