staging: fbtft: use init function instead of init sequence

This patch converts the default init sequence of the ST7789V
display controller into an init function, as init sequences
are considered deprecated by the maintainers of fbtft.
Signed-off-by: Dennis Menschel <menschel-d@posteo.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/fbtft/fb_st7789v.c

@@ -15,6 +15,7 @@
  */
 
 #include <linux/bitops.h>
+#include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
@@ -69,63 +70,67 @@ enum st7789v_command {
 #define MADCTL_MY BIT(7) /* bitmask for page address order */
 
 /**
- * default_init_sequence - default initialization sequence for ST7789V
+ * init_display() - initialize the display controller
  *
- * Most of the commands in this init sequence set their parameters to the
+ * @par: FBTFT parameter object
+ *
+ * Most of the commands in this init function set their parameters to the
  * same default values which are already in place after the display has been
  * powered up. (The main exception to this rule is the pixel format which
  * would default to 18 instead of 16 bit per pixel.)
  * Nonetheless, this sequence can be used as a template for concrete
  * displays which usually need some adjustments.
+ *
+ * Return: 0 on success, < 0 if error occurred.
  */
-static int default_init_sequence[] = {
+static int init_display(struct fbtft_par *par)
+{
 	/* turn off sleep mode */
-	-1, MIPI_DCS_EXIT_SLEEP_MODE,
-	-2, 120,
+	write_reg(par, MIPI_DCS_EXIT_SLEEP_MODE);
+	mdelay(120);
 
 	/* set pixel format to RGB-565 */
-	-1, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_16BIT,
+	write_reg(par, MIPI_DCS_SET_PIXEL_FORMAT, MIPI_DCS_PIXEL_FMT_16BIT);
 
-	-1, PORCTRL, 0x08, 0x08, 0x00, 0x22, 0x22,
+	write_reg(par, PORCTRL, 0x08, 0x08, 0x00, 0x22, 0x22);
 
 	/*
 	 * VGH = 13.26V
 	 * VGL = -10.43V
 	 */
-	-1, GCTRL, 0x35,
+	write_reg(par, GCTRL, 0x35);
 
 	/*
 	 * VDV and VRH register values come from command write
 	 * (instead of NVM)
 	 */
-	-1, VDVVRHEN, 0x01, 0xFF,
+	write_reg(par, VDVVRHEN, 0x01, 0xFF);
 
 	/*
 	 * VAP =  4.1V + (VCOM + VCOM offset + 0.5 * VDV)
 	 * VAN = -4.1V + (VCOM + VCOM offset + 0.5 * VDV)
 	 */
-	-1, VRHS, 0x0B,
+	write_reg(par, VRHS, 0x0B);
 
 	/* VDV = 0V */
-	-1, VDVS, 0x20,
+	write_reg(par, VDVS, 0x20);
 
 	/* VCOM = 0.9V */
-	-1, VCOMS, 0x20,
+	write_reg(par, VCOMS, 0x20);
 
 	/* VCOM offset = 0V */
-	-1, VCMOFSET, 0x20,
+	write_reg(par, VCMOFSET, 0x20);
 
 	/*
 	 * AVDD = 6.8V
 	 * AVCL = -4.8V
 	 * VDS = 2.3V
 	 */
-	-1, PWCTRL1, 0xA4, 0xA1,
+	write_reg(par, PWCTRL1, 0xA4, 0xA1);
 
-	-1, MIPI_DCS_SET_DISPLAY_ON,
-
-	-3,
-};
+	write_reg(par, MIPI_DCS_SET_DISPLAY_ON);
+	return 0;
+}
 
 /**
  * set_var() - apply LCD properties like rotation and BGR mode
@@ -237,11 +242,11 @@ static struct fbtft_display display = {
 	.regwidth = 8,
 	.width = 240,
 	.height = 320,
-	.init_sequence = default_init_sequence,
 	.gamma_num = 2,
 	.gamma_len = 14,
 	.gamma = DEFAULT_GAMMA,
 	.fbtftops = {
+		.init_display = init_display,
 		.set_var = set_var,
 		.set_gamma = set_gamma,
 		.blank = blank,