[PATCH v2] staging: fbtft: fb_st7789v: Initialize the Display

From: Oliver Graute
Date: Wed May 13 2020 - 10:32:14 EST


From: Oliver Graute <oliver.graute@xxxxxxxxxxxxxxxxx>

Set Gamma Values and Register Values for the HSD20_IPS Panel

Signed-off-by: Oliver Graute <oliver.graute@xxxxxxxxxxxxxxxxx>
---

need information howto set HSD20_IPS Panel at run time and not at compile time

Changes for v2:
- added define for HSD20_IPS_GAMMA values
- check for HSD20_IPS define
- enabled MIPI_DCS_ENTER_INVERT_MODE

drivers/staging/fbtft/fb_st7789v.c | 32 +++++++++++++++++++++++++-----
1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/staging/fbtft/fb_st7789v.c b/drivers/staging/fbtft/fb_st7789v.c
index 3c3f387936e8..ebc17e05ecd0 100644
--- a/drivers/staging/fbtft/fb_st7789v.c
+++ b/drivers/staging/fbtft/fb_st7789v.c
@@ -20,6 +20,12 @@
"70 2C 2E 15 10 09 48 33 53 0B 19 18 20 25\n" \
"70 2C 2E 15 10 09 48 33 53 0B 19 18 20 25"

+#define HSD20_IPS_GAMMA \
+ "D0 05 0A 09 08 05 2E 44 45 0F 17 16 2B 33\n" \
+ "D0 05 0A 09 08 05 2E 43 45 0F 16 16 2B 33"
+
+#define HSD20_IPS "true"
+
/**
* enum st7789v_command - ST7789V display controller commands
*
@@ -82,14 +88,20 @@ static int init_display(struct fbtft_par *par)

/* set pixel format to RGB-565 */
write_reg(par, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_16BIT);
+ if (HSD20_IPS)
+ write_reg(par, PORCTRL, 0x05, 0x05, 0x00, 0x33, 0x33);

- write_reg(par, PORCTRL, 0x08, 0x08, 0x00, 0x22, 0x22);
+ else
+ write_reg(par, PORCTRL, 0x08, 0x08, 0x00, 0x22, 0x22);

/*
* VGH = 13.26V
* VGL = -10.43V
*/
- write_reg(par, GCTRL, 0x35);
+ if (HSD20_IPS)
+ write_reg(par, GCTRL, 0x75);
+ else
+ write_reg(par, GCTRL, 0x35);

/*
* VDV and VRH register values come from command write
@@ -101,13 +113,19 @@ static int init_display(struct fbtft_par *par)
* VAP = 4.1V + (VCOM + VCOM offset + 0.5 * VDV)
* VAN = -4.1V + (VCOM + VCOM offset + 0.5 * VDV)
*/
- write_reg(par, VRHS, 0x0B);
+ if (HSD20_IPS)
+ write_reg(par, VRHS, 0x13);
+ else
+ write_reg(par, VRHS, 0x0B);

/* VDV = 0V */
write_reg(par, VDVS, 0x20);

/* VCOM = 0.9V */
- write_reg(par, VCOMS, 0x20);
+ if (HSD20_IPS)
+ write_reg(par, VCOMS, 0x22);
+ else
+ write_reg(par, VCOMS, 0x20);

/* VCOM offset = 0V */
write_reg(par, VCMOFSET, 0x20);
@@ -120,6 +138,10 @@ static int init_display(struct fbtft_par *par)
write_reg(par, PWCTRL1, 0xA4, 0xA1);

write_reg(par, MIPI_DCS_SET_DISPLAY_ON);
+
+ if (HSD20_IPS)
+ write_reg(par, MIPI_DCS_ENTER_INVERT_MODE);
+
return 0;
}

@@ -234,7 +256,7 @@ static struct fbtft_display display = {
.height = 320,
.gamma_num = 2,
.gamma_len = 14,
- .gamma = DEFAULT_GAMMA,
+ .gamma = HSD20_IPS_GAMMA,
.fbtftops = {
.init_display = init_display,
.set_var = set_var,
--
2.17.1