drm/panel/panel-sitronix-st7701: Support SPI config and RGB data
authorDave Stevenson <dave.stevenson@raspberrypi.com>
Tue, 1 Feb 2022 15:27:01 +0000 (15:27 +0000)
committerDom Cobley <popcornmix@gmail.com>
Mon, 19 Feb 2024 11:33:27 +0000 (11:33 +0000)
The ST7701 supports numerous different interface mechanisms for
MIPI DSI, RGB, or SPI. The driver was only implementing DSI input,
so add RGB parallel input with SPI configuration.

Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
drivers/gpu/drm/panel/panel-sitronix-st7701.c

index 036ac40..16e8b5e 100644 (file)
@@ -7,16 +7,21 @@
 #include <drm/drm_mipi_dsi.h>
 #include <drm/drm_modes.h>
 #include <drm/drm_panel.h>
+#include <drm/drm_print.h>
 
 #include <linux/bitfield.h>
 #include <linux/gpio/consumer.h>
 #include <linux/delay.h>
+#include <linux/media-bus-format.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/regulator/consumer.h>
+#include <linux/spi/spi.h>
 
 #include <video/mipi_display.h>
 
+#define SPI_DATA_FLAG                  0x100
+
 /* Command2 BKx selection command */
 #define DSI_CMD2BKX_SEL                        0xFF
 #define DSI_CMD1                       0
 #define DSI_CMD2_BK1_SPD2              0xC2 /* Source EQ2 Setting */
 #define DSI_CMD2_BK1_MIPISET1          0xD0 /* MIPI Setting 1 */
 
+/*
+ * Command2 with BK function selection.
+ *
+ * BIT[4].....CN2
+ * BIT[1:0]...BKXSEL
+ * 1:00 = CMD2BK0, Command2 BK0
+ * 1:01 = CMD2BK1, Command2 BK1
+ * 1:11 = CMD2BK3, Command2 BK3
+ * 0:00 = Command2 disable
+ */
+#define DSI_CMD2BK0_SEL                        0x10
+#define DSI_CMD2BK1_SEL                        0x11
+#define DSI_CMD2BK3_SEL                        0x13
+#define DSI_CMD2BKX_SEL_NONE           0x00
+#define SPI_CMD2BK3_SEL                        (SPI_DATA_FLAG | DSI_CMD2BK3_SEL)
+#define SPI_CMD2BK1_SEL                        (SPI_DATA_FLAG | DSI_CMD2BK1_SEL)
+#define SPI_CMD2BK0_SEL                        (SPI_DATA_FLAG | DSI_CMD2BK0_SEL)
+#define SPI_CMD2BKX_SEL_NONE           (SPI_DATA_FLAG | DSI_CMD2BKX_SEL_NONE)
+
 /* Command2, BK0 bytes */
 #define DSI_CMD2_BK0_GAMCTRL_AJ_MASK   GENMASK(7, 6)
 #define DSI_CMD2_BK0_GAMCTRL_VC0_MASK  GENMASK(3, 0)
@@ -100,11 +124,23 @@ enum op_bias {
 
 struct st7701;
 
+struct st7701;
+
+enum st7701_ctrl_if {
+       ST7701_CTRL_DSI,
+       ST7701_CTRL_SPI,
+};
+
 struct st7701_panel_desc {
        const struct drm_display_mode *mode;
        unsigned int lanes;
        enum mipi_dsi_pixel_format format;
+       u32 mediabus_format;
        unsigned int panel_sleep_delay;
+       void (*init_sequence)(struct st7701 *st7701);
+       unsigned int conn_type;
+       enum st7701_ctrl_if interface;
+       u32 bus_flags;
 
        /* TFT matrix driver configuration, panel specific. */
        const u8        pv_gamma[16];   /* Positive voltage gamma control */
@@ -130,6 +166,9 @@ struct st7701_panel_desc {
 struct st7701 {
        struct drm_panel panel;
        struct mipi_dsi_device *dsi;
+       struct spi_device *spi;
+       const struct device *dev;
+
        const struct st7701_panel_desc *desc;
 
        struct regulator_bulk_data supplies[2];
@@ -192,7 +231,23 @@ static void st7701_switch_cmd_bkx(struct st7701 *st7701, bool cmd2, u8 bkx)
        ST7701_DSI(st7701, DSI_CMD2BKX_SEL, 0x77, 0x01, 0x00, 0x00, val);
 }
 
-static void st7701_init_sequence(struct st7701 *st7701)
+#define ST7701_SPI(st7701, seq...)                             \
+       {                                                       \
+               const u16 d[] = { seq };                        \
+               struct spi_transfer xfer = { };                 \
+               struct spi_message spi;                         \
+                                                               \
+               spi_message_init(&spi);                         \
+                                                               \
+               xfer.tx_buf = d;                                \
+               xfer.bits_per_word = 9;                         \
+               xfer.len = sizeof(u16) * ARRAY_SIZE(d);         \
+                                                               \
+               spi_message_add_tail(&xfer, &spi);              \
+               spi_sync((st7701)->spi, &spi);                  \
+       }
+
+static void ts8550b_init_sequence(struct st7701 *st7701)
 {
        const struct st7701_panel_desc *desc = st7701->desc;
        const struct drm_display_mode *mode = desc->mode;
@@ -423,6 +478,111 @@ static void kd50t048a_gip_sequence(struct st7701 *st7701)
                   0xFF, 0xFF, 0xFF, 0xFF, 0x10, 0x45, 0x67, 0x98, 0xBA);
 }
 
+static void txw210001b0_init_sequence(struct st7701 *st7701)
+{
+       ST7701_SPI(st7701, MIPI_DCS_SOFT_RESET);
+
+       usleep_range(5000, 7000);
+
+       ST7701_SPI(st7701, DSI_CMD2BKX_SEL,
+                  0x177, 0x101, 0x100, 0x100, SPI_CMD2BK0_SEL);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK0_LNESET, 0x13B, 0x100);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK0_PORCTRL, 0x10B, 0x102);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK0_INVSEL, 0x100, 0x102);
+
+       ST7701_SPI(st7701, 0xCC, 0x110);
+
+       /*
+        * Gamma option B:
+        * Positive Voltage Gamma Control
+        */
+       ST7701_SPI(st7701, DSI_CMD2_BK0_PVGAMCTRL,
+                  0x102, 0x113, 0x11B, 0x10D, 0x110, 0x105, 0x108, 0x107,
+                  0x107, 0x124, 0x104, 0x111, 0x10E, 0x12C, 0x133, 0x11D);
+
+       /* Negative Voltage Gamma Control */
+       ST7701_SPI(st7701, DSI_CMD2_BK0_NVGAMCTRL,
+                  0x105, 0x113, 0x11B, 0x10D, 0x111, 0x105, 0x108, 0x107,
+                  0x107, 0x124, 0x104, 0x111, 0x10E, 0x12C, 0x133, 0x11D);
+
+       ST7701_SPI(st7701, DSI_CMD2BKX_SEL,
+                  0x177, 0x101, 0x100, 0x100, SPI_CMD2BK1_SEL);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_VRHS, 0x15D);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_VCOM, 0x143);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_VGHSS, 0x181);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_TESTCMD, 0x180);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_VGLS, 0x143);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_PWCTLR1, 0x185);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_PWCTLR2, 0x120);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_SPD1, 0x178);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_SPD2, 0x178);
+
+       ST7701_SPI(st7701, DSI_CMD2_BK1_MIPISET1, 0x188);
+
+       ST7701_SPI(st7701, 0xE0, 0x100, 0x100, 0x102);
+
+       ST7701_SPI(st7701, 0xE1,
+                  0x103, 0x1A0, 0x100, 0x100, 0x104, 0x1A0, 0x100, 0x100,
+                  0x100, 0x120, 0x120);
+
+       ST7701_SPI(st7701, 0xE2,
+                  0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100,
+                  0x100, 0x100, 0x100, 0x100, 0x100);
+
+       ST7701_SPI(st7701, 0xE3, 0x100, 0x100, 0x111, 0x100);
+
+       ST7701_SPI(st7701, 0xE4, 0x122, 0x100);
+
+       ST7701_SPI(st7701, 0xE5,
+                  0x105, 0x1EC, 0x1A0, 0x1A0, 0x107, 0x1EE, 0x1A0, 0x1A0,
+                  0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100);
+
+       ST7701_SPI(st7701, 0xE6, 0x100, 0x100, 0x111, 0x100);
+
+       ST7701_SPI(st7701, 0xE7, 0x122, 0x100);
+
+       ST7701_SPI(st7701, 0xE8,
+                  0x106, 0x1ED, 0x1A0, 0x1A0, 0x108, 0x1EF, 0x1A0, 0x1A0,
+                  0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100, 0x100);
+
+       ST7701_SPI(st7701, 0xEB,
+                  0x100, 0x100, 0x140, 0x140, 0x100, 0x100, 0x100);
+
+       ST7701_SPI(st7701, 0xED,
+                  0x1FF, 0x1FF, 0x1FF, 0x1BA, 0x10A, 0x1BF, 0x145, 0x1FF,
+                  0x1FF, 0x154, 0x1FB, 0x1A0, 0x1AB, 0x1FF, 0x1FF, 0x1FF);
+
+       ST7701_SPI(st7701, 0xEF, 0x110, 0x10D, 0x104, 0x108, 0x13F, 0x11F);
+
+       ST7701_SPI(st7701, DSI_CMD2BKX_SEL,
+                  0x177, 0x101, 0x100, 0x100, SPI_CMD2BK3_SEL);
+
+       ST7701_SPI(st7701, 0xEF, 0x108);
+
+       ST7701_SPI(st7701, DSI_CMD2BKX_SEL,
+                  0x177, 0x101, 0x100, 0x100, SPI_CMD2BKX_SEL_NONE);
+
+       ST7701_SPI(st7701, 0xCD, 0x108);  /* RGB format COLCTRL */
+
+       ST7701_SPI(st7701, 0x36, 0x108); /* MadCtl */
+
+       ST7701_SPI(st7701, 0x3A, 0x166);  /* Colmod */
+
+       ST7701_SPI(st7701, MIPI_DCS_EXIT_SLEEP_MODE);
+}
+
 static int st7701_prepare(struct drm_panel *panel)
 {
        struct st7701 *st7701 = panel_to_st7701(panel);
@@ -439,7 +599,7 @@ static int st7701_prepare(struct drm_panel *panel)
        gpiod_set_value(st7701->reset, 1);
        msleep(150);
 
-       st7701_init_sequence(st7701);
+       st7701->desc->init_sequence(st7701);
 
        if (st7701->desc->gip_sequence)
                st7701->desc->gip_sequence(st7701);
@@ -454,7 +614,15 @@ static int st7701_enable(struct drm_panel *panel)
 {
        struct st7701 *st7701 = panel_to_st7701(panel);
 
-       ST7701_DSI(st7701, MIPI_DCS_SET_DISPLAY_ON, 0x00);
+       switch (st7701->desc->interface) {
+       case ST7701_CTRL_DSI:
+               ST7701_DSI(st7701, MIPI_DCS_SET_DISPLAY_ON, 0x00);
+               break;
+       case ST7701_CTRL_SPI:
+               ST7701_SPI(st7701, MIPI_DCS_SET_DISPLAY_ON);
+               msleep(30);
+               break;
+       }
 
        return 0;
 }
@@ -463,7 +631,14 @@ static int st7701_disable(struct drm_panel *panel)
 {
        struct st7701 *st7701 = panel_to_st7701(panel);
 
-       ST7701_DSI(st7701, MIPI_DCS_SET_DISPLAY_OFF, 0x00);
+       switch (st7701->desc->interface) {
+       case ST7701_CTRL_DSI:
+               ST7701_DSI(st7701, MIPI_DCS_SET_DISPLAY_OFF, 0x00);
+               break;
+       case ST7701_CTRL_SPI:
+               ST7701_SPI(st7701, MIPI_DCS_SET_DISPLAY_OFF);
+               break;
+       }
 
        return 0;
 }
@@ -472,7 +647,14 @@ static int st7701_unprepare(struct drm_panel *panel)
 {
        struct st7701 *st7701 = panel_to_st7701(panel);
 
-       ST7701_DSI(st7701, MIPI_DCS_ENTER_SLEEP_MODE, 0x00);
+       switch (st7701->desc->interface) {
+       case ST7701_CTRL_DSI:
+               ST7701_DSI(st7701, MIPI_DCS_ENTER_SLEEP_MODE, 0x00);
+               break;
+       case ST7701_CTRL_SPI:
+               ST7701_SPI(st7701, MIPI_DCS_ENTER_SLEEP_MODE);
+               break;
+       }
 
        msleep(st7701->sleep_delay);
 
@@ -503,7 +685,7 @@ static int st7701_get_modes(struct drm_panel *panel,
 
        mode = drm_mode_duplicate(connector->dev, desc_mode);
        if (!mode) {
-               dev_err(&st7701->dsi->dev, "failed to add mode %ux%u@%u\n",
+               dev_err(st7701->dev, "failed to add mode %ux%u@%u\n",
                        desc_mode->hdisplay, desc_mode->vdisplay,
                        drm_mode_vrefresh(desc_mode));
                return -ENOMEM;
@@ -512,6 +694,12 @@ static int st7701_get_modes(struct drm_panel *panel,
        drm_mode_set_name(mode);
        drm_mode_probed_add(connector, mode);
 
+       if (st7701->desc->mediabus_format)
+               drm_display_info_set_bus_formats(&connector->display_info,
+                                                &st7701->desc->mediabus_format,
+                                                1);
+       connector->display_info.bus_flags = 0;
+
        connector->display_info.width_mm = desc_mode->width_mm;
        connector->display_info.height_mm = desc_mode->height_mm;
 
@@ -521,6 +709,9 @@ static int st7701_get_modes(struct drm_panel *panel,
         */
        drm_connector_set_panel_orientation(connector, st7701->orientation);
 
+       if (st7701->desc->bus_flags)
+               connector->display_info.bus_flags = st7701->desc->bus_flags;
+
        return 1;
 }
 
@@ -564,6 +755,9 @@ static const struct st7701_panel_desc ts8550b_desc = {
        .lanes = 2,
        .format = MIPI_DSI_FMT_RGB888,
        .panel_sleep_delay = 80, /* panel need extra 80ms for sleep out cmd */
+       .init_sequence = ts8550b_init_sequence,
+       .conn_type = DRM_MODE_CONNECTOR_DSI,
+       .interface = ST7701_CTRL_DSI,
 
        .pv_gamma = {
                CFIELD_PREP(DSI_CMD2_BK0_GAMCTRL_AJ_MASK, 0) |
@@ -759,6 +953,26 @@ static const struct drm_display_mode kd50t048a_mode = {
        .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
 };
 
+static const struct drm_display_mode txw210001b0_mode = {
+       .clock          = 19200,
+
+       .hdisplay       = 480,
+       .hsync_start    = 480 + 10,
+       .hsync_end      = 480 + 10 + 16,
+       .htotal         = 480 + 10 + 16 + 56,
+
+       .vdisplay       = 480,
+       .vsync_start    = 480 + 15,
+       .vsync_end      = 480 + 15 + 60,
+       .vtotal         = 480 + 15 + 60 + 15,
+
+       .width_mm       = 53,
+       .height_mm      = 53,
+       .flags = DRM_MODE_FLAG_NHSYNC | DRM_MODE_FLAG_NVSYNC,
+
+       .type = DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED,
+};
+
 static const struct st7701_panel_desc kd50t048a_desc = {
        .mode = &kd50t048a_mode,
        .lanes = 2,
@@ -839,42 +1053,54 @@ static const struct st7701_panel_desc kd50t048a_desc = {
        .gip_sequence = kd50t048a_gip_sequence,
 };
 
-static int st7701_dsi_probe(struct mipi_dsi_device *dsi)
+static const struct st7701_panel_desc txw210001b0_desc = {
+       .mode = &txw210001b0_mode,
+       .mediabus_format = MEDIA_BUS_FMT_RGB888_1X24,
+       .init_sequence = txw210001b0_init_sequence,
+       .conn_type = DRM_MODE_CONNECTOR_DPI,
+       .interface = ST7701_CTRL_SPI,
+       .bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE,
+};
+
+static const struct st7701_panel_desc hyperpixel2r_desc = {
+       .mode = &txw210001b0_mode,
+       .mediabus_format = MEDIA_BUS_FMT_RGB666_1X24_CPADHI,
+       .init_sequence = txw210001b0_init_sequence,
+       .conn_type = DRM_MODE_CONNECTOR_DPI,
+       .interface = ST7701_CTRL_SPI,
+       .bus_flags = DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE,
+};
+
+static int st7701_probe(struct device *dev, struct st7701 **ret_st7701)
 {
        const struct st7701_panel_desc *desc;
        struct st7701 *st7701;
        int ret;
 
-       st7701 = devm_kzalloc(&dsi->dev, sizeof(*st7701), GFP_KERNEL);
+       st7701 = devm_kzalloc(dev, sizeof(*st7701), GFP_KERNEL);
        if (!st7701)
                return -ENOMEM;
 
-       desc = of_device_get_match_data(&dsi->dev);
-       dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
-                         MIPI_DSI_MODE_LPM | MIPI_DSI_CLOCK_NON_CONTINUOUS;
-       dsi->format = desc->format;
-       dsi->lanes = desc->lanes;
+       desc = of_device_get_match_data(dev);
+       if (!desc)
+               return -EINVAL;
 
        st7701->supplies[0].supply = "VCC";
        st7701->supplies[1].supply = "IOVCC";
 
-       ret = devm_regulator_bulk_get(&dsi->dev, ARRAY_SIZE(st7701->supplies),
+       ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(st7701->supplies),
                                      st7701->supplies);
        if (ret < 0)
                return ret;
 
-       st7701->reset = devm_gpiod_get(&dsi->dev, "reset", GPIOD_OUT_LOW);
+       st7701->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
        if (IS_ERR(st7701->reset)) {
-               dev_err(&dsi->dev, "Couldn't get our reset GPIO\n");
+               dev_err(dev, "Couldn't get our reset GPIO\n");
                return PTR_ERR(st7701->reset);
        }
 
-       ret = of_drm_get_panel_orientation(dsi->dev.of_node, &st7701->orientation);
-       if (ret < 0)
-               return dev_err_probe(&dsi->dev, ret, "Failed to get orientation\n");
-
-       drm_panel_init(&st7701->panel, &dsi->dev, &st7701_funcs,
-                      DRM_MODE_CONNECTOR_DSI);
+       drm_panel_init(&st7701->panel, dev, &st7701_funcs,
+                      desc->conn_type);
 
        /**
         * Once sleep out has been issued, ST7701 IC required to wait 120ms
@@ -893,14 +1119,39 @@ static int st7701_dsi_probe(struct mipi_dsi_device *dsi)
 
        drm_panel_add(&st7701->panel);
 
+       st7701->desc = desc;
+       st7701->dev = dev;
+
+       *ret_st7701 = st7701;
+
+       return 0;
+}
+
+static int st7701_dsi_probe(struct mipi_dsi_device *dsi)
+{
+       struct st7701 *st7701;
+       int ret;
+
+       ret = st7701_probe(&dsi->dev, &st7701);
+
+       if (ret)
+               return ret;
+
+       dsi->mode_flags = MIPI_DSI_MODE_VIDEO;
+       dsi->format = st7701->desc->format;
+       dsi->lanes = st7701->desc->lanes;
+
        mipi_dsi_set_drvdata(dsi, st7701);
        st7701->dsi = dsi;
-       st7701->desc = desc;
 
        ret = mipi_dsi_attach(dsi);
        if (ret)
                goto err_attach;
 
+       ret = of_drm_get_panel_orientation(dsi->dev.of_node, &st7701->orientation);
+       if (ret < 0)
+               return dev_err_probe(&dsi->dev, ret, "Failed to get orientation\n");
+
        return 0;
 
 err_attach:
@@ -916,23 +1167,115 @@ static void st7701_dsi_remove(struct mipi_dsi_device *dsi)
        drm_panel_remove(&st7701->panel);
 }
 
-static const struct of_device_id st7701_of_match[] = {
+static const struct of_device_id st7701_dsi_of_match[] = {
        { .compatible = "densitron,dmt028vghmcmi-1a", .data = &dmt028vghmcmi_1a_desc },
        { .compatible = "elida,kd50t048a", .data = &kd50t048a_desc },
        { .compatible = "techstar,ts8550b", .data = &ts8550b_desc },
        { }
 };
-MODULE_DEVICE_TABLE(of, st7701_of_match);
+MODULE_DEVICE_TABLE(of, st7701_dsi_of_match);
 
 static struct mipi_dsi_driver st7701_dsi_driver = {
        .probe          = st7701_dsi_probe,
        .remove         = st7701_dsi_remove,
        .driver = {
                .name           = "st7701",
-               .of_match_table = st7701_of_match,
+               .of_match_table = st7701_dsi_of_match,
+       },
+};
+
+/* SPI display  probe */
+static const struct of_device_id st7701_spi_of_match[] = {
+       {       .compatible = "txw,txw210001b0",
+               .data = &txw210001b0_desc,
+       }, {
+               .compatible = "pimoroni,hyperpixel2round",
+               .data = &hyperpixel2r_desc,
+       }, {
+               /* sentinel */
+       }
+};
+MODULE_DEVICE_TABLE(of, st7701_spi_of_match);
+
+static int st7701_spi_probe(struct spi_device *spi)
+{
+       struct st7701 *st7701;
+       int ret;
+
+       spi->mode = SPI_MODE_3;
+       spi->bits_per_word = 9;
+       ret = spi_setup(spi);
+       if (ret < 0) {
+               dev_err(&spi->dev, "failed to setup SPI: %d\n", ret);
+               return ret;
+       }
+
+       ret = st7701_probe(&spi->dev, &st7701);
+
+       if (ret)
+               return ret;
+
+       spi_set_drvdata(spi, st7701);
+       st7701->spi = spi;
+
+       return 0;
+}
+
+static void st7701_spi_remove(struct spi_device *spi)
+{
+       struct st7701 *ctx = spi_get_drvdata(spi);
+
+       drm_panel_remove(&ctx->panel);
+}
+
+static const struct spi_device_id st7701_spi_ids[] = {
+       { "txw210001b0", 0 },
+       { "hyperpixel2round", 0 },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(spi, st7701_spi_ids);
+
+static struct spi_driver st7701_spi_driver = {
+       .probe = st7701_spi_probe,
+       .remove = st7701_spi_remove,
+       .driver = {
+               .name = "st7701",
+               .of_match_table = st7701_spi_of_match,
        },
+       .id_table = st7701_spi_ids,
 };
-module_mipi_dsi_driver(st7701_dsi_driver);
+
+static int __init panel_st7701_init(void)
+{
+       int err;
+
+       err = spi_register_driver(&st7701_spi_driver);
+       if (err < 0)
+               return err;
+
+       if (IS_ENABLED(CONFIG_DRM_MIPI_DSI)) {
+               err = mipi_dsi_driver_register(&st7701_dsi_driver);
+               if (err < 0)
+                       goto err_did_spi_register;
+       }
+
+       return 0;
+
+err_did_spi_register:
+       spi_unregister_driver(&st7701_spi_driver);
+
+       return err;
+}
+module_init(panel_st7701_init);
+
+static void __exit panel_st7701_exit(void)
+{
+       if (IS_ENABLED(CONFIG_DRM_MIPI_DSI))
+               mipi_dsi_driver_unregister(&st7701_dsi_driver);
+
+       spi_unregister_driver(&st7701_spi_driver);
+}
+module_exit(panel_st7701_exit);
 
 MODULE_AUTHOR("Jagan Teki <jagan@amarulasolutions.com>");
 MODULE_DESCRIPTION("Sitronix ST7701 LCD Panel Driver");