// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)

#include <drm/clients/drm_client_setup.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_connector.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_drv.h>
#include <drm/drm_fb_dma_helper.h>
#include <drm/drm_fbdev_dma.h>
#include <drm/drm_format_helper.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_dma_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_modes.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_rect.h>
#include <linux/bitrev.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/kthread.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/pwm.h>
#include <linux/spi/spi.h>

#define SHARP_MODE_PERIOD 8
#define SHARP_ADDR_PERIOD 8
#define SHARP_DUMMY_PERIOD 8

#define SHARP_MEMORY_DISPLAY_MAINTAIN_MODE 0
#define SHARP_MEMORY_DISPLAY_UPDATE_MODE 1
#define SHARP_MEMORY_DISPLAY_CLEAR_MODE 4

enum sharp_memory_model {
        LS010B7DH04,
        LS011B7DH03,
        LS012B7DD01,
        LS013B7DH03,
        LS013B7DH05,
        LS018B7DH02,
        LS027B7DH01,
        LS027B7DH01A,
        LS032B7DD02,
        LS044Q7DH01,
};

enum sharp_memory_vcom_mode {
        SHARP_MEMORY_SOFTWARE_VCOM,
        SHARP_MEMORY_EXTERNAL_VCOM,
        SHARP_MEMORY_PWM_VCOM
};

struct sharp_memory_device {
        struct drm_device drm;
        struct spi_device *spi;

        const struct drm_display_mode *mode;

        struct drm_crtc crtc;
        struct drm_plane plane;
        struct drm_encoder encoder;
        struct drm_connector connector;

        struct gpio_desc *enable_gpio;

        struct task_struct *sw_vcom_signal;
        struct pwm_device *pwm_vcom_signal;

        enum sharp_memory_vcom_mode vcom_mode;
        u8 vcom;

        u32 pitch;
        u32 tx_buffer_size;
        u8 *tx_buffer;

        /* When vcom_mode == "software" a kthread is used to periodically send a
         * 'maintain display' message over spi. This mutex ensures tx_buffer access
         * and spi bus usage is synchronized in this case.
         */
        struct mutex tx_mutex;
};

static inline int sharp_memory_spi_write(struct spi_device *spi, void *buf, size_t len)
{
        /* Reverse the bit order */
        for (u8 *b = buf; b < ((u8 *)buf) + len; ++b)
                *b = bitrev8(*b);

        return spi_write(spi, buf, len);
}

static inline struct sharp_memory_device *drm_to_sharp_memory_device(struct drm_device *drm)
{
        return container_of(drm, struct sharp_memory_device, drm);
}

DEFINE_DRM_GEM_DMA_FOPS(sharp_memory_fops);

static const struct drm_driver sharp_memory_drm_driver = {
        .driver_features        = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
        .fops                   = &sharp_memory_fops,
        DRM_GEM_DMA_DRIVER_OPS_VMAP,
        DRM_FBDEV_DMA_DRIVER_OPS,
        .name                   = "sharp_memory_display",
        .desc                   = "Sharp Display Memory LCD",
        .major                  = 1,
        .minor                  = 0,
};

static inline void sharp_memory_set_tx_buffer_mode(u8 *buffer, u8 mode, u8 vcom)
{
        *buffer = mode | (vcom << 1);
}

static inline void sharp_memory_set_tx_buffer_addresses(u8 *buffer,
                                                        struct drm_rect clip,
                                                        u32 pitch)
{
        for (u32 line = 0; line < clip.y2; ++line)
                buffer[line * pitch] = line + 1;
}

static void sharp_memory_set_tx_buffer_data(u8 *buffer,
                                            struct drm_framebuffer *fb,
                                            const struct iosys_map *vmap,
                                            struct drm_rect clip,
                                            u32 pitch,
                                            struct drm_format_conv_state *fmtcnv_state)
{
        int ret;
        struct iosys_map dst;

        ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);
        if (ret)
                return;

        iosys_map_set_vaddr(&dst, buffer);

        drm_fb_xrgb8888_to_mono(&dst, &pitch, vmap, fb, &clip, fmtcnv_state);

        drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);
}

static int sharp_memory_update_display(struct sharp_memory_device *smd,
                                       struct drm_framebuffer *fb,
                                       const struct iosys_map *vmap,
                                       struct drm_rect clip,
                                       struct drm_format_conv_state *fmtcnv_state)
{
        int ret;
        u32 pitch = smd->pitch;
        u8 vcom = smd->vcom;
        u8 *tx_buffer = smd->tx_buffer;
        u32 tx_buffer_size = smd->tx_buffer_size;

        mutex_lock(&smd->tx_mutex);

        /* Populate the transmit buffer with frame data */
        sharp_memory_set_tx_buffer_mode(&tx_buffer[0],
                                        SHARP_MEMORY_DISPLAY_UPDATE_MODE, vcom);
        sharp_memory_set_tx_buffer_addresses(&tx_buffer[1], clip, pitch);
        sharp_memory_set_tx_buffer_data(&tx_buffer[2], fb, vmap, clip, pitch, fmtcnv_state);

        ret = sharp_memory_spi_write(smd->spi, tx_buffer, tx_buffer_size);

        mutex_unlock(&smd->tx_mutex);

        return ret;
}

static int sharp_memory_maintain_display(struct sharp_memory_device *smd)
{
        int ret;
        u8 vcom = smd->vcom;
        u8 *tx_buffer = smd->tx_buffer;

        mutex_lock(&smd->tx_mutex);

        sharp_memory_set_tx_buffer_mode(&tx_buffer[0], SHARP_MEMORY_DISPLAY_MAINTAIN_MODE, vcom);
        tx_buffer[1] = 0; /* Write dummy data */
        ret = sharp_memory_spi_write(smd->spi, tx_buffer, 2);

        mutex_unlock(&smd->tx_mutex);

        return ret;
}

static int sharp_memory_clear_display(struct sharp_memory_device *smd)
{
        int ret;
        u8 vcom = smd->vcom;
        u8 *tx_buffer = smd->tx_buffer;

        mutex_lock(&smd->tx_mutex);

        sharp_memory_set_tx_buffer_mode(&tx_buffer[0], SHARP_MEMORY_DISPLAY_CLEAR_MODE, vcom);
        tx_buffer[1] = 0; /* write dummy data */
        ret = sharp_memory_spi_write(smd->spi, tx_buffer, 2);

        mutex_unlock(&smd->tx_mutex);

        return ret;
}

static void sharp_memory_fb_dirty(struct drm_framebuffer *fb, const struct iosys_map *vmap,
                                  struct drm_rect *rect,
                                  struct drm_format_conv_state *fmtconv_state)
{
        struct drm_rect clip;
        struct sharp_memory_device *smd = drm_to_sharp_memory_device(fb->dev);

        /* Always update a full line regardless of what is dirty */
        clip.x1 = 0;
        clip.x2 = fb->width;
        clip.y1 = rect->y1;
        clip.y2 = rect->y2;

        sharp_memory_update_display(smd, fb, vmap, clip, fmtconv_state);
}

static int sharp_memory_plane_atomic_check(struct drm_plane *plane,
                                           struct drm_atomic_state *state)
{
        struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane);
        struct sharp_memory_device *smd;
        struct drm_crtc_state *crtc_state;

        smd = container_of(plane, struct sharp_memory_device, plane);
        crtc_state = drm_atomic_get_new_crtc_state(state, &smd->crtc);

        return drm_atomic_helper_check_plane_state(plane_state, crtc_state,
                                                   DRM_PLANE_NO_SCALING,
                                                   DRM_PLANE_NO_SCALING,
                                                   false, false);
}

static void sharp_memory_plane_atomic_update(struct drm_plane *plane,
                                             struct drm_atomic_state *state)
{
        struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state, plane);
        struct drm_plane_state *plane_state = plane->state;
        struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state);
        struct sharp_memory_device *smd;
        struct drm_rect rect;

        smd = container_of(plane, struct sharp_memory_device, plane);
        if (!smd->crtc.state->active)
                return;

        if (drm_atomic_helper_damage_merged(old_state, plane_state, &rect))
                sharp_memory_fb_dirty(plane_state->fb, shadow_plane_state->data,
                                      &rect, &shadow_plane_state->fmtcnv_state);
}

static const struct drm_plane_helper_funcs sharp_memory_plane_helper_funcs = {
        .prepare_fb = drm_gem_plane_helper_prepare_fb,
        .atomic_check = sharp_memory_plane_atomic_check,
        .atomic_update = sharp_memory_plane_atomic_update,
        DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
};

static bool sharp_memory_format_mod_supported(struct drm_plane *plane,
                                              u32 format,
                                              u64 modifier)
{
        return modifier == DRM_FORMAT_MOD_LINEAR;
}

static const struct drm_plane_funcs sharp_memory_plane_funcs = {
        .update_plane = drm_atomic_helper_update_plane,
        .disable_plane = drm_atomic_helper_disable_plane,
        .destroy = drm_plane_cleanup,
        DRM_GEM_SHADOW_PLANE_FUNCS,
        .format_mod_supported = sharp_memory_format_mod_supported,
};

static enum drm_mode_status sharp_memory_crtc_mode_valid(struct drm_crtc *crtc,
                                                         const struct drm_display_mode *mode)
{
        struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev);

        return drm_crtc_helper_mode_valid_fixed(crtc, mode, smd->mode);
}

static int sharp_memory_crtc_check(struct drm_crtc *crtc,
                                   struct drm_atomic_state *state)
{
        struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
        int ret;

        if (!crtc_state->enable)
                goto out;

        ret = drm_atomic_helper_check_crtc_primary_plane(crtc_state);
        if (ret)
                return ret;

out:
        return drm_atomic_add_affected_planes(state, crtc);
}

static int sharp_memory_sw_vcom_signal_thread(void *data)
{
        struct sharp_memory_device *smd = data;

        while (!kthread_should_stop()) {
                smd->vcom ^= 1; /* Toggle vcom */
                sharp_memory_maintain_display(smd);
                msleep(1000);
        }

        return 0;
}

static void sharp_memory_crtc_enable(struct drm_crtc *crtc,
                                     struct drm_atomic_state *state)
{
        struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev);

        sharp_memory_clear_display(smd);

        if (smd->enable_gpio)
                gpiod_set_value(smd->enable_gpio, 1);
}

static void sharp_memory_crtc_disable(struct drm_crtc *crtc,
                                      struct drm_atomic_state *state)
{
        struct sharp_memory_device *smd = drm_to_sharp_memory_device(crtc->dev);

        sharp_memory_clear_display(smd);

        if (smd->enable_gpio)
                gpiod_set_value(smd->enable_gpio, 0);
}

static const struct drm_crtc_helper_funcs sharp_memory_crtc_helper_funcs = {
        .mode_valid = sharp_memory_crtc_mode_valid,
        .atomic_check = sharp_memory_crtc_check,
        .atomic_enable = sharp_memory_crtc_enable,
        .atomic_disable = sharp_memory_crtc_disable,
};

static const struct drm_crtc_funcs sharp_memory_crtc_funcs = {
        .reset = drm_atomic_helper_crtc_reset,
        .destroy = drm_crtc_cleanup,
        .set_config = drm_atomic_helper_set_config,
        .page_flip = drm_atomic_helper_page_flip,
        .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
        .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
};

static const struct drm_encoder_funcs sharp_memory_encoder_funcs = {
        .destroy = drm_encoder_cleanup,
};

static int sharp_memory_connector_get_modes(struct drm_connector *connector)
{
        struct sharp_memory_device *smd = drm_to_sharp_memory_device(connector->dev);

        return drm_connector_helper_get_modes_fixed(connector, smd->mode);
}

static const struct drm_connector_helper_funcs sharp_memory_connector_hfuncs = {
        .get_modes = sharp_memory_connector_get_modes,
};

static const struct drm_connector_funcs sharp_memory_connector_funcs = {
        .reset = drm_atomic_helper_connector_reset,
        .fill_modes = drm_helper_probe_single_connector_modes,
        .destroy = drm_connector_cleanup,
        .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
        .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,

};

static const struct drm_mode_config_funcs sharp_memory_mode_config_funcs = {
        .fb_create = drm_gem_fb_create_with_dirty,
        .atomic_check = drm_atomic_helper_check,
        .atomic_commit = drm_atomic_helper_commit,
};

static const struct drm_display_mode sharp_memory_ls010b7dh04_mode = {
        DRM_SIMPLE_MODE(128, 128, 18, 18),
};

static const struct drm_display_mode sharp_memory_ls011b7dh03_mode = {
        DRM_SIMPLE_MODE(160, 68, 25, 10),
};

static const struct drm_display_mode sharp_memory_ls012b7dd01_mode = {
        DRM_SIMPLE_MODE(184, 38, 29, 6),
};

static const struct drm_display_mode sharp_memory_ls013b7dh03_mode = {
        DRM_SIMPLE_MODE(128, 128, 23, 23),
};

static const struct drm_display_mode sharp_memory_ls013b7dh05_mode = {
        DRM_SIMPLE_MODE(144, 168, 20, 24),
};

static const struct drm_display_mode sharp_memory_ls018b7dh02_mode = {
        DRM_SIMPLE_MODE(230, 303, 27, 36),
};

static const struct drm_display_mode sharp_memory_ls027b7dh01_mode = {
        DRM_SIMPLE_MODE(400, 240, 58, 35),
};

static const struct drm_display_mode sharp_memory_ls032b7dd02_mode = {
        DRM_SIMPLE_MODE(336, 536, 42, 68),
};

static const struct drm_display_mode sharp_memory_ls044q7dh01_mode = {
        DRM_SIMPLE_MODE(320, 240, 89, 67),
};

static const struct spi_device_id sharp_memory_ids[] = {
        {"ls010b7dh04", (kernel_ulong_t)&sharp_memory_ls010b7dh04_mode},
        {"ls011b7dh03", (kernel_ulong_t)&sharp_memory_ls011b7dh03_mode},
        {"ls012b7dd01", (kernel_ulong_t)&sharp_memory_ls012b7dd01_mode},
        {"ls013b7dh03", (kernel_ulong_t)&sharp_memory_ls013b7dh03_mode},
        {"ls013b7dh05", (kernel_ulong_t)&sharp_memory_ls013b7dh05_mode},
        {"ls018b7dh02", (kernel_ulong_t)&sharp_memory_ls018b7dh02_mode},
        {"ls027b7dh01", (kernel_ulong_t)&sharp_memory_ls027b7dh01_mode},
        {"ls027b7dh01a", (kernel_ulong_t)&sharp_memory_ls027b7dh01_mode},
        {"ls032b7dd02", (kernel_ulong_t)&sharp_memory_ls032b7dd02_mode},
        {"ls044q7dh01", (kernel_ulong_t)&sharp_memory_ls044q7dh01_mode},
        {},
};
MODULE_DEVICE_TABLE(spi, sharp_memory_ids);

static const struct of_device_id sharp_memory_of_match[] = {
        {.compatible = "sharp,ls010b7dh04", &sharp_memory_ls010b7dh04_mode},
        {.compatible = "sharp,ls011b7dh03", &sharp_memory_ls011b7dh03_mode},
        {.compatible = "sharp,ls012b7dd01", &sharp_memory_ls012b7dd01_mode},
        {.compatible = "sharp,ls013b7dh03", &sharp_memory_ls013b7dh03_mode},
        {.compatible = "sharp,ls013b7dh05", &sharp_memory_ls013b7dh05_mode},
        {.compatible = "sharp,ls018b7dh02", &sharp_memory_ls018b7dh02_mode},
        {.compatible = "sharp,ls027b7dh01", &sharp_memory_ls027b7dh01_mode},
        {.compatible = "sharp,ls027b7dh01a", &sharp_memory_ls027b7dh01_mode},
        {.compatible = "sharp,ls032b7dd02", &sharp_memory_ls032b7dd02_mode},
        {.compatible = "sharp,ls044q7dh01", &sharp_memory_ls044q7dh01_mode},
        {},
};
MODULE_DEVICE_TABLE(of, sharp_memory_of_match);

static const u32 sharp_memory_formats[] = {
        DRM_FORMAT_XRGB8888,
};

static int sharp_memory_pipe_init(struct drm_device *dev,
                                  struct sharp_memory_device *smd,
                                  const u32 *formats, unsigned int format_count,
                                  const u64 *format_modifiers)
{
        int ret;
        struct drm_encoder *encoder = &smd->encoder;
        struct drm_plane *plane = &smd->plane;
        struct drm_crtc *crtc = &smd->crtc;
        struct drm_connector *connector = &smd->connector;

        drm_plane_helper_add(plane, &sharp_memory_plane_helper_funcs);
        ret = drm_universal_plane_init(dev, plane, 0,
                                       &sharp_memory_plane_funcs,
                                       formats, format_count,
                                       format_modifiers,
                                       DRM_PLANE_TYPE_PRIMARY, NULL);
        if (ret)
                return ret;

        drm_crtc_helper_add(crtc, &sharp_memory_crtc_helper_funcs);
        ret = drm_crtc_init_with_planes(dev, crtc, plane, NULL,
                                        &sharp_memory_crtc_funcs, NULL);
        if (ret)
                return ret;

        encoder->possible_crtcs = drm_crtc_mask(crtc);
        ret = drm_encoder_init(dev, encoder, &sharp_memory_encoder_funcs,
                               DRM_MODE_ENCODER_NONE, NULL);
        if (ret)
                return ret;

        ret = drm_connector_init(&smd->drm, &smd->connector,
                                 &sharp_memory_connector_funcs,
                                 DRM_MODE_CONNECTOR_SPI);
        if (ret)
                return ret;

        drm_connector_helper_add(&smd->connector,
                                 &sharp_memory_connector_hfuncs);

        return drm_connector_attach_encoder(connector, encoder);
}

static int sharp_memory_init_pwm_vcom_signal(struct sharp_memory_device *smd)
{
        int ret;
        struct device *dev = &smd->spi->dev;
        struct pwm_state pwm_state;

        smd->pwm_vcom_signal = devm_pwm_get(dev, NULL);
        if (IS_ERR(smd->pwm_vcom_signal))
                return dev_err_probe(dev, PTR_ERR(smd->pwm_vcom_signal),
                                     "Could not get pwm device\n");

        pwm_init_state(smd->pwm_vcom_signal, &pwm_state);
        pwm_set_relative_duty_cycle(&pwm_state, 1, 10);
        pwm_state.enabled = true;
        ret = pwm_apply_might_sleep(smd->pwm_vcom_signal, &pwm_state);
        if (ret)
                return dev_err_probe(dev, -EINVAL, "Could not apply pwm state\n");

        return 0;
}

static int sharp_memory_probe(struct spi_device *spi)
{
        int ret;
        struct device *dev;
        struct sharp_memory_device *smd;
        struct drm_device *drm;
        const char *vcom_mode_str;

        dev = &spi->dev;

        ret = spi_setup(spi);
        if (ret < 0)
                return dev_err_probe(dev, ret, "Failed to setup spi device\n");

        if (!dev->coherent_dma_mask) {
                ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));
                if (ret)
                        return dev_err_probe(dev, ret, "Failed to set dma mask\n");
        }

        smd = devm_drm_dev_alloc(dev, &sharp_memory_drm_driver,
                                 struct sharp_memory_device, drm);
        if (IS_ERR(smd))
                return PTR_ERR(smd);

        spi_set_drvdata(spi, smd);

        smd->spi = spi;
        drm = &smd->drm;
        ret = drmm_mode_config_init(drm);
        if (ret)
                return dev_err_probe(dev, ret, "Failed to initialize drm config\n");

        smd->enable_gpio = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_HIGH);
        if (!smd->enable_gpio)
                dev_warn(dev, "Enable gpio not defined\n");

        drm->mode_config.funcs = &sharp_memory_mode_config_funcs;
        smd->mode = spi_get_device_match_data(spi);

        smd->pitch = (SHARP_ADDR_PERIOD + smd->mode->hdisplay + SHARP_DUMMY_PERIOD) / 8;
        smd->tx_buffer_size = (SHARP_MODE_PERIOD +
                               (SHARP_ADDR_PERIOD + (smd->mode->hdisplay) + SHARP_DUMMY_PERIOD) *
                               smd->mode->vdisplay) / 8;

        smd->tx_buffer = devm_kzalloc(dev, smd->tx_buffer_size, GFP_KERNEL);
        if (!smd->tx_buffer)
                return -ENOMEM;

        mutex_init(&smd->tx_mutex);

        /*
         * VCOM is a signal that prevents DC bias from being built up in
         * the panel resulting in pixels being forever stuck in one state.
         *
         * This driver supports three different methods to generate this
         * signal depending on EXTMODE pin:
         *
         * software (EXTMODE = L) - This mode uses a kthread to
         * periodically send a "maintain display" message to the display,
         * toggling the vcom bit on and off with each message
         *
         * external (EXTMODE = H) - This mode relies on an external
         * clock to generate the signal on the EXTCOMM pin
         *
         * pwm (EXTMODE = H) - This mode uses a pwm device to generate
         * the signal on the EXTCOMM pin
         *
         */
        if (device_property_read_string(dev, "sharp,vcom-mode", &vcom_mode_str))
                return dev_err_probe(dev, -EINVAL,
                                     "Unable to find sharp,vcom-mode node in device tree\n");

        if (!strcmp("software", vcom_mode_str)) {
                smd->vcom_mode = SHARP_MEMORY_SOFTWARE_VCOM;
                smd->sw_vcom_signal = kthread_run(sharp_memory_sw_vcom_signal_thread,
                                                  smd, "sw_vcom_signal");

        } else if (!strcmp("external", vcom_mode_str)) {
                smd->vcom_mode = SHARP_MEMORY_EXTERNAL_VCOM;

        } else if (!strcmp("pwm", vcom_mode_str)) {
                smd->vcom_mode = SHARP_MEMORY_PWM_VCOM;
                ret = sharp_memory_init_pwm_vcom_signal(smd);
                if (ret)
                        return ret;
        } else {
                return dev_err_probe(dev, -EINVAL, "Invalid value set for vcom-mode\n");
        }

        drm->mode_config.min_width = smd->mode->hdisplay;
        drm->mode_config.max_width = smd->mode->hdisplay;
        drm->mode_config.min_height = smd->mode->vdisplay;
        drm->mode_config.max_height = smd->mode->vdisplay;

        ret = sharp_memory_pipe_init(drm, smd, sharp_memory_formats,
                                     ARRAY_SIZE(sharp_memory_formats),
                                     NULL);
        if (ret)
                return dev_err_probe(dev, ret, "Failed to initialize display pipeline.\n");

        drm_plane_enable_fb_damage_clips(&smd->plane);
        drm_mode_config_reset(drm);

        ret = drm_dev_register(drm, 0);
        if (ret)
                return dev_err_probe(dev, ret, "Failed to register drm device.\n");

        drm_client_setup(drm, NULL);

        return 0;
}

static void sharp_memory_remove(struct spi_device *spi)
{
        struct sharp_memory_device *smd = spi_get_drvdata(spi);

        drm_dev_unplug(&smd->drm);
        drm_atomic_helper_shutdown(&smd->drm);

        switch (smd->vcom_mode) {
        case SHARP_MEMORY_SOFTWARE_VCOM:
                kthread_stop(smd->sw_vcom_signal);
                break;

        case SHARP_MEMORY_EXTERNAL_VCOM:
                break;

        case SHARP_MEMORY_PWM_VCOM:
                pwm_disable(smd->pwm_vcom_signal);
                break;
        }
}

static struct spi_driver sharp_memory_spi_driver = {
        .driver = {
                .name = "sharp_memory",
                .of_match_table = sharp_memory_of_match,
        },
        .probe = sharp_memory_probe,
        .remove = sharp_memory_remove,
        .id_table = sharp_memory_ids,
};
module_spi_driver(sharp_memory_spi_driver);

MODULE_AUTHOR("Alex Lanzano <lanzano.alex@gmail.com>");
MODULE_DESCRIPTION("SPI Protocol driver for the sharp_memory display");
MODULE_LICENSE("GPL");