// SPDX-License-Identifier: GPL-2.0-only

#include <linux/aperture.h>
#include <linux/clk.h>
#include <linux/minmax.h>
#include <linux/of_address.h>
#include <linux/of_clk.h>
#include <linux/of_reserved_mem.h>
#include <linux/platform_data/simplefb.h>
#include <linux/platform_device.h>
#include <linux/pm_domain.h>
#include <linux/regulator/consumer.h>

#include <drm/clients/drm_client_setup.h>
#include <drm/drm_atomic.h>
#include <drm/drm_atomic_state_helper.h>
#include <drm/drm_connector.h>
#include <drm/drm_damage_helper.h>
#include <drm/drm_device.h>
#include <drm/drm_drv.h>
#include <drm/drm_fbdev_shmem.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_gem_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_gem_shmem_helper.h>
#include <drm/drm_managed.h>
#include <drm/drm_modeset_helper_vtables.h>
#include <drm/drm_print.h>
#include <drm/drm_probe_helper.h>

#include "drm_sysfb_helper.h"

#define DRIVER_NAME     "simpledrm"
#define DRIVER_DESC     "DRM driver for simple-framebuffer platform devices"
#define DRIVER_MAJOR    1
#define DRIVER_MINOR    0

/*
 * Helpers for simplefb
 */

static int
simplefb_get_validated_int(struct drm_device *dev, const char *name,
                           uint32_t value)
{
        return drm_sysfb_get_validated_int(dev, name, value, INT_MAX);
}

static int
simplefb_get_validated_int0(struct drm_device *dev, const char *name,
                            uint32_t value)
{
        return drm_sysfb_get_validated_int0(dev, name, value, INT_MAX);
}

static const struct drm_format_info *
simplefb_get_validated_format(struct drm_device *dev, const char *format_name)
{
        static const struct simplefb_format formats[] = SIMPLEFB_FORMATS;
        const struct simplefb_format *fmt = formats;
        const struct simplefb_format *end = fmt + ARRAY_SIZE(formats);
        const struct drm_format_info *info;

        if (!format_name) {
                drm_err(dev, "simplefb: missing framebuffer format\n");
                return ERR_PTR(-EINVAL);
        }

        while (fmt < end) {
                if (!strcmp(format_name, fmt->name)) {
                        info = drm_format_info(fmt->fourcc);
                        if (!info)
                                return ERR_PTR(-EINVAL);
                        return info;
                }
                ++fmt;
        }

        drm_err(dev, "simplefb: unknown framebuffer format %s\n",
                format_name);

        return ERR_PTR(-EINVAL);
}

static int
simplefb_get_width_pd(struct drm_device *dev,
                      const struct simplefb_platform_data *pd)
{
        return simplefb_get_validated_int0(dev, "width", pd->width);
}

static int
simplefb_get_height_pd(struct drm_device *dev,
                       const struct simplefb_platform_data *pd)
{
        return simplefb_get_validated_int0(dev, "height", pd->height);
}

static int
simplefb_get_stride_pd(struct drm_device *dev,
                       const struct simplefb_platform_data *pd)
{
        return simplefb_get_validated_int(dev, "stride", pd->stride);
}

static const struct drm_format_info *
simplefb_get_format_pd(struct drm_device *dev,
                       const struct simplefb_platform_data *pd)
{
        return simplefb_get_validated_format(dev, pd->format);
}

static int
simplefb_read_u32_of(struct drm_device *dev, struct device_node *of_node,
                     const char *name, u32 *value)
{
        int ret = of_property_read_u32(of_node, name, value);

        if (ret)
                drm_err(dev, "simplefb: cannot parse framebuffer %s: error %d\n",
                        name, ret);
        return ret;
}

static int
simplefb_read_string_of(struct drm_device *dev, struct device_node *of_node,
                        const char *name, const char **value)
{
        int ret = of_property_read_string(of_node, name, value);

        if (ret)
                drm_err(dev, "simplefb: cannot parse framebuffer %s: error %d\n",
                        name, ret);
        return ret;
}

static int
simplefb_get_width_of(struct drm_device *dev, struct device_node *of_node)
{
        u32 width;
        int ret = simplefb_read_u32_of(dev, of_node, "width", &width);

        if (ret)
                return ret;
        return simplefb_get_validated_int0(dev, "width", width);
}

static int
simplefb_get_height_of(struct drm_device *dev, struct device_node *of_node)
{
        u32 height;
        int ret = simplefb_read_u32_of(dev, of_node, "height", &height);

        if (ret)
                return ret;
        return simplefb_get_validated_int0(dev, "height", height);
}

static int
simplefb_get_stride_of(struct drm_device *dev, struct device_node *of_node)
{
        u32 stride;
        int ret = simplefb_read_u32_of(dev, of_node, "stride", &stride);

        if (ret)
                return ret;
        return simplefb_get_validated_int(dev, "stride", stride);
}

static const struct drm_format_info *
simplefb_get_format_of(struct drm_device *dev, struct device_node *of_node)
{
        const char *format;
        int ret = simplefb_read_string_of(dev, of_node, "format", &format);

        if (ret)
                return ERR_PTR(ret);
        return simplefb_get_validated_format(dev, format);
}

static struct resource *
simplefb_get_memory_of(struct drm_device *dev, struct device_node *of_node)
{
        struct resource r, *res;
        int err;

        err = of_reserved_mem_region_to_resource(of_node, 0, &r);
        if (err)
                return NULL;

        res = devm_kmemdup(dev->dev, &r, sizeof(r), GFP_KERNEL);
        if (!res)
                return ERR_PTR(-ENOMEM);

        if (of_property_present(of_node, "reg"))
                drm_warn(dev, "preferring \"memory-region\" over \"reg\" property\n");

        return res;
}

/*
 * Simple Framebuffer device
 */

struct simpledrm_device {
        struct drm_sysfb_device sysfb;

        /* clocks */
#if defined CONFIG_OF && defined CONFIG_COMMON_CLK
        unsigned int clk_count;
        struct clk **clks;
#endif
        /* regulators */
#if defined CONFIG_OF && defined CONFIG_REGULATOR
        unsigned int regulator_count;
        struct regulator **regulators;
#endif
        /* power-domains */
#if defined CONFIG_OF && defined CONFIG_PM_GENERIC_DOMAINS
        int pwr_dom_count;
        struct device **pwr_dom_devs;
        struct device_link **pwr_dom_links;
#endif

        /* modesetting */
        u32 formats[DRM_SYSFB_PLANE_NFORMATS(1)];
        struct drm_plane primary_plane;
        struct drm_crtc crtc;
        struct drm_encoder encoder;
        struct drm_connector connector;
};

/*
 * Hardware
 */

#if defined CONFIG_OF && defined CONFIG_COMMON_CLK
/*
 * Clock handling code.
 *
 * Here we handle the clocks property of our "simple-framebuffer" dt node.
 * This is necessary so that we can make sure that any clocks needed by
 * the display engine that the bootloader set up for us (and for which it
 * provided a simplefb dt node), stay up, for the life of the simplefb
 * driver.
 *
 * When the driver unloads, we cleanly disable, and then release the clocks.
 *
 * We only complain about errors here, no action is taken as the most likely
 * error can only happen due to a mismatch between the bootloader which set
 * up simplefb, and the clock definitions in the device tree. Chances are
 * that there are no adverse effects, and if there are, a clean teardown of
 * the fb probe will not help us much either. So just complain and carry on,
 * and hope that the user actually gets a working fb at the end of things.
 */

static void simpledrm_device_release_clocks(void *res)
{
        struct simpledrm_device *sdev = res;
        unsigned int i;

        for (i = 0; i < sdev->clk_count; ++i) {
                if (sdev->clks[i]) {
                        clk_disable_unprepare(sdev->clks[i]);
                        clk_put(sdev->clks[i]);
                }
        }
}

static int simpledrm_device_init_clocks(struct simpledrm_device *sdev)
{
        struct drm_device *dev = &sdev->sysfb.dev;
        struct platform_device *pdev = to_platform_device(dev->dev);
        struct device_node *of_node = pdev->dev.of_node;
        struct clk *clock;
        unsigned int i;
        int ret;

        if (dev_get_platdata(&pdev->dev) || !of_node)
                return 0;

        sdev->clk_count = of_clk_get_parent_count(of_node);
        if (!sdev->clk_count)
                return 0;

        sdev->clks = drmm_kzalloc(dev, sdev->clk_count * sizeof(sdev->clks[0]),
                                  GFP_KERNEL);
        if (!sdev->clks)
                return -ENOMEM;

        for (i = 0; i < sdev->clk_count; ++i) {
                clock = of_clk_get(of_node, i);
                if (IS_ERR(clock)) {
                        ret = PTR_ERR(clock);
                        if (ret == -EPROBE_DEFER)
                                goto err;
                        drm_err(dev, "clock %u not found: %d\n", i, ret);
                        continue;
                }
                ret = clk_prepare_enable(clock);
                if (ret) {
                        drm_err(dev, "failed to enable clock %u: %d\n",
                                i, ret);
                        clk_put(clock);
                        continue;
                }
                sdev->clks[i] = clock;
        }

        return devm_add_action_or_reset(&pdev->dev,
                                        simpledrm_device_release_clocks,
                                        sdev);

err:
        while (i) {
                --i;
                if (sdev->clks[i]) {
                        clk_disable_unprepare(sdev->clks[i]);
                        clk_put(sdev->clks[i]);
                }
        }
        return ret;
}
#else
static int simpledrm_device_init_clocks(struct simpledrm_device *sdev)
{
        return 0;
}
#endif

#if defined CONFIG_OF && defined CONFIG_REGULATOR

#define SUPPLY_SUFFIX "-supply"

/*
 * Regulator handling code.
 *
 * Here we handle the num-supplies and vin*-supply properties of our
 * "simple-framebuffer" dt node. This is necessary so that we can make sure
 * that any regulators needed by the display hardware that the bootloader
 * set up for us (and for which it provided a simplefb dt node), stay up,
 * for the life of the simplefb driver.
 *
 * When the driver unloads, we cleanly disable, and then release the
 * regulators.
 *
 * We only complain about errors here, no action is taken as the most likely
 * error can only happen due to a mismatch between the bootloader which set
 * up simplefb, and the regulator definitions in the device tree. Chances are
 * that there are no adverse effects, and if there are, a clean teardown of
 * the fb probe will not help us much either. So just complain and carry on,
 * and hope that the user actually gets a working fb at the end of things.
 */

static void simpledrm_device_release_regulators(void *res)
{
        struct simpledrm_device *sdev = res;
        unsigned int i;

        for (i = 0; i < sdev->regulator_count; ++i) {
                if (sdev->regulators[i]) {
                        regulator_disable(sdev->regulators[i]);
                        regulator_put(sdev->regulators[i]);
                }
        }
}

static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
{
        struct drm_device *dev = &sdev->sysfb.dev;
        struct platform_device *pdev = to_platform_device(dev->dev);
        struct device_node *of_node = pdev->dev.of_node;
        struct property *prop;
        struct regulator *regulator;
        const char *p;
        unsigned int count = 0, i = 0;
        int ret;

        if (dev_get_platdata(&pdev->dev) || !of_node)
                return 0;

        /* Count the number of regulator supplies */
        for_each_property_of_node(of_node, prop) {
                p = strstr(prop->name, SUPPLY_SUFFIX);
                if (p && p != prop->name)
                        ++count;
        }

        if (!count)
                return 0;

        sdev->regulators = drmm_kzalloc(dev,
                                        count * sizeof(sdev->regulators[0]),
                                        GFP_KERNEL);
        if (!sdev->regulators)
                return -ENOMEM;

        for_each_property_of_node(of_node, prop) {
                char name[32]; /* 32 is max size of property name */
                size_t len;

                p = strstr(prop->name, SUPPLY_SUFFIX);
                if (!p || p == prop->name)
                        continue;
                len = strlen(prop->name) - strlen(SUPPLY_SUFFIX) + 1;
                strscpy(name, prop->name, min(sizeof(name), len));

                regulator = regulator_get_optional(&pdev->dev, name);
                if (IS_ERR(regulator)) {
                        ret = PTR_ERR(regulator);
                        if (ret == -EPROBE_DEFER)
                                goto err;
                        drm_err(dev, "regulator %s not found: %d\n",
                                name, ret);
                        continue;
                }

                ret = regulator_enable(regulator);
                if (ret) {
                        drm_err(dev, "failed to enable regulator %u: %d\n",
                                i, ret);
                        regulator_put(regulator);
                        continue;
                }

                sdev->regulators[i++] = regulator;
        }
        sdev->regulator_count = i;

        return devm_add_action_or_reset(&pdev->dev,
                                        simpledrm_device_release_regulators,
                                        sdev);

err:
        while (i) {
                --i;
                if (sdev->regulators[i]) {
                        regulator_disable(sdev->regulators[i]);
                        regulator_put(sdev->regulators[i]);
                }
        }
        return ret;
}
#else
static int simpledrm_device_init_regulators(struct simpledrm_device *sdev)
{
        return 0;
}
#endif

#if defined CONFIG_OF && defined CONFIG_PM_GENERIC_DOMAINS
/*
 * Generic power domain handling code.
 *
 * Here we handle the power-domains properties of our "simple-framebuffer"
 * dt node. This is only necessary if there is more than one power-domain.
 * A single power-domains is handled automatically by the driver core. Multiple
 * power-domains have to be handled by drivers since the driver core can't know
 * the correct power sequencing. Power sequencing is not an issue for simpledrm
 * since the bootloader has put the power domains already in the correct state.
 * simpledrm has only to ensure they remain active for its lifetime.
 *
 * When the driver unloads, we detach from the power-domains.
 *
 * We only complain about errors here, no action is taken as the most likely
 * error can only happen due to a mismatch between the bootloader which set
 * up the "simple-framebuffer" dt node, and the PM domain providers in the
 * device tree. Chances are that there are no adverse effects, and if there are,
 * a clean teardown of the fb probe will not help us much either. So just
 * complain and carry on, and hope that the user actually gets a working fb at
 * the end of things.
 */
static void simpledrm_device_detach_genpd(void *res)
{
        int i;
        struct simpledrm_device *sdev = res;

        if (sdev->pwr_dom_count <= 1)
                return;

        for (i = sdev->pwr_dom_count - 1; i >= 0; i--) {
                if (sdev->pwr_dom_links[i])
                        device_link_del(sdev->pwr_dom_links[i]);
                if (!IS_ERR_OR_NULL(sdev->pwr_dom_devs[i]))
                        dev_pm_domain_detach(sdev->pwr_dom_devs[i], true);
        }
}

static int simpledrm_device_attach_genpd(struct simpledrm_device *sdev)
{
        struct device *dev = sdev->sysfb.dev.dev;
        int i;

        sdev->pwr_dom_count = of_count_phandle_with_args(dev->of_node, "power-domains",
                                                         "#power-domain-cells");
        /*
         * Single power-domain devices are handled by driver core nothing to do
         * here. The same for device nodes without "power-domains" property.
         */
        if (sdev->pwr_dom_count <= 1)
                return 0;

        sdev->pwr_dom_devs = devm_kcalloc(dev, sdev->pwr_dom_count,
                                               sizeof(*sdev->pwr_dom_devs),
                                               GFP_KERNEL);
        if (!sdev->pwr_dom_devs)
                return -ENOMEM;

        sdev->pwr_dom_links = devm_kcalloc(dev, sdev->pwr_dom_count,
                                                sizeof(*sdev->pwr_dom_links),
                                                GFP_KERNEL);
        if (!sdev->pwr_dom_links)
                return -ENOMEM;

        for (i = 0; i < sdev->pwr_dom_count; i++) {
                sdev->pwr_dom_devs[i] = dev_pm_domain_attach_by_id(dev, i);
                if (IS_ERR(sdev->pwr_dom_devs[i])) {
                        int ret = PTR_ERR(sdev->pwr_dom_devs[i]);
                        if (ret == -EPROBE_DEFER) {
                                simpledrm_device_detach_genpd(sdev);
                                return ret;
                        }
                        drm_warn(&sdev->sysfb.dev,
                                 "pm_domain_attach_by_id(%u) failed: %d\n", i, ret);
                        continue;
                }

                sdev->pwr_dom_links[i] = device_link_add(dev,
                                                         sdev->pwr_dom_devs[i],
                                                         DL_FLAG_STATELESS |
                                                         DL_FLAG_PM_RUNTIME |
                                                         DL_FLAG_RPM_ACTIVE);
                if (!sdev->pwr_dom_links[i])
                        drm_warn(&sdev->sysfb.dev, "failed to link power-domain %d\n", i);
        }

        return devm_add_action_or_reset(dev, simpledrm_device_detach_genpd, sdev);
}
#else
static int simpledrm_device_attach_genpd(struct simpledrm_device *sdev)
{
        return 0;
}
#endif

/*
 * Modesetting
 */

static const u64 simpledrm_primary_plane_format_modifiers[] = {
        DRM_SYSFB_PLANE_FORMAT_MODIFIERS,
};

static const struct drm_plane_helper_funcs simpledrm_primary_plane_helper_funcs = {
        DRM_SYSFB_PLANE_HELPER_FUNCS,
};

static const struct drm_plane_funcs simpledrm_primary_plane_funcs = {
        DRM_SYSFB_PLANE_FUNCS,
        .destroy = drm_plane_cleanup,
};

static const struct drm_crtc_helper_funcs simpledrm_crtc_helper_funcs = {
        DRM_SYSFB_CRTC_HELPER_FUNCS,
};

static const struct drm_crtc_funcs simpledrm_crtc_funcs = {
        DRM_SYSFB_CRTC_FUNCS,
        .destroy = drm_crtc_cleanup,
};

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

static const struct drm_connector_helper_funcs simpledrm_connector_helper_funcs = {
        DRM_SYSFB_CONNECTOR_HELPER_FUNCS,
};

static const struct drm_connector_funcs simpledrm_connector_funcs = {
        DRM_SYSFB_CONNECTOR_FUNCS,
        .destroy = drm_connector_cleanup,
};

static const struct drm_mode_config_funcs simpledrm_mode_config_funcs = {
        DRM_SYSFB_MODE_CONFIG_FUNCS,
};

/*
 * Init / Cleanup
 */

static struct simpledrm_device *simpledrm_device_create(struct drm_driver *drv,
                                                        struct platform_device *pdev)
{
        const struct simplefb_platform_data *pd = dev_get_platdata(&pdev->dev);
        struct device_node *of_node = pdev->dev.of_node;
        struct simpledrm_device *sdev;
        struct drm_sysfb_device *sysfb;
        struct drm_device *dev;
        int width, height, stride;
        int width_mm = 0, height_mm = 0;
        struct device_node *panel_node;
        const struct drm_format_info *format;
        struct resource *res, *mem = NULL;
        struct drm_plane *primary_plane;
        struct drm_crtc *crtc;
        struct drm_encoder *encoder;
        struct drm_connector *connector;
        unsigned long max_width, max_height;
        size_t nformats;
        int ret;

        sdev = devm_drm_dev_alloc(&pdev->dev, drv, struct simpledrm_device, sysfb.dev);
        if (IS_ERR(sdev))
                return ERR_CAST(sdev);
        sysfb = &sdev->sysfb;
        dev = &sysfb->dev;
        platform_set_drvdata(pdev, sdev);

        /*
         * Hardware settings
         */

        ret = simpledrm_device_init_clocks(sdev);
        if (ret)
                return ERR_PTR(ret);
        ret = simpledrm_device_init_regulators(sdev);
        if (ret)
                return ERR_PTR(ret);
        ret = simpledrm_device_attach_genpd(sdev);
        if (ret)
                return ERR_PTR(ret);

        if (pd) {
                width = simplefb_get_width_pd(dev, pd);
                if (width < 0)
                        return ERR_PTR(width);
                height = simplefb_get_height_pd(dev, pd);
                if (height < 0)
                        return ERR_PTR(height);
                stride = simplefb_get_stride_pd(dev, pd);
                if (stride < 0)
                        return ERR_PTR(stride);
                format = simplefb_get_format_pd(dev, pd);
                if (IS_ERR(format))
                        return ERR_CAST(format);
        } else if (of_node) {
                width = simplefb_get_width_of(dev, of_node);
                if (width < 0)
                        return ERR_PTR(width);
                height = simplefb_get_height_of(dev, of_node);
                if (height < 0)
                        return ERR_PTR(height);
                stride = simplefb_get_stride_of(dev, of_node);
                if (stride < 0)
                        return ERR_PTR(stride);
                format = simplefb_get_format_of(dev, of_node);
                if (IS_ERR(format))
                        return ERR_CAST(format);
                mem = simplefb_get_memory_of(dev, of_node);
                if (IS_ERR(mem))
                        return ERR_CAST(mem);
                panel_node = of_parse_phandle(of_node, "panel", 0);
                if (panel_node) {
                        simplefb_read_u32_of(dev, panel_node, "width-mm", &width_mm);
                        simplefb_read_u32_of(dev, panel_node, "height-mm", &height_mm);
                        of_node_put(panel_node);
                }
        } else {
                drm_err(dev, "no simplefb configuration found\n");
                return ERR_PTR(-ENODEV);
        }
        if (!stride) {
                stride = drm_format_info_min_pitch(format, 0, width);
                if (drm_WARN_ON(dev, !stride))
                        return ERR_PTR(-EINVAL);
        }

        sysfb->fb_mode = drm_sysfb_mode(width, height, width_mm, height_mm);
        sysfb->fb_format = format;
        sysfb->fb_pitch = stride;

        drm_dbg(dev, "display mode={" DRM_MODE_FMT "}\n", DRM_MODE_ARG(&sysfb->fb_mode));
        drm_dbg(dev, "framebuffer format=%p4cc, size=%dx%d, stride=%d byte\n",
                &format->format, width, height, stride);

        /*
         * Memory management
         */

        if (mem) {
                void *screen_base;

                ret = devm_aperture_acquire_for_platform_device(pdev, mem->start,
                                                                resource_size(mem));
                if (ret) {
                        drm_err(dev, "could not acquire memory range %pr: %d\n", mem, ret);
                        return ERR_PTR(ret);
                }

                drm_dbg(dev, "using system memory framebuffer at %pr\n", mem);

                screen_base = devm_memremap(dev->dev, mem->start, resource_size(mem), MEMREMAP_WC);
                if (IS_ERR(screen_base))
                        return screen_base;

                iosys_map_set_vaddr(&sysfb->fb_addr, screen_base);
        } else {
                void __iomem *screen_base;

                res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
                if (!res)
                        return ERR_PTR(-EINVAL);

                ret = devm_aperture_acquire_for_platform_device(pdev, res->start,
                                                                resource_size(res));
                if (ret) {
                        drm_err(dev, "could not acquire memory range %pr: %d\n", res, ret);
                        return ERR_PTR(ret);
                }

                drm_dbg(dev, "using I/O memory framebuffer at %pr\n", res);

                mem = devm_request_mem_region(&pdev->dev, res->start, resource_size(res),
                                              drv->name);
                if (!mem) {
                        /*
                         * We cannot make this fatal. Sometimes this comes from magic
                         * spaces our resource handlers simply don't know about. Use
                         * the I/O-memory resource as-is and try to map that instead.
                         */
                        drm_warn(dev, "could not acquire memory region %pr\n", res);
                        mem = res;
                }

                screen_base = devm_ioremap_wc(&pdev->dev, mem->start, resource_size(mem));
                if (!screen_base)
                        return ERR_PTR(-ENOMEM);

                iosys_map_set_vaddr_iomem(&sysfb->fb_addr, screen_base);
        }

        /*
         * Modesetting
         */

        ret = drmm_mode_config_init(dev);
        if (ret)
                return ERR_PTR(ret);

        max_width = max_t(unsigned long, width, DRM_SHADOW_PLANE_MAX_WIDTH);
        max_height = max_t(unsigned long, height, DRM_SHADOW_PLANE_MAX_HEIGHT);

        dev->mode_config.min_width = width;
        dev->mode_config.max_width = max_width;
        dev->mode_config.min_height = height;
        dev->mode_config.max_height = max_height;
        dev->mode_config.preferred_depth = format->depth;
        dev->mode_config.funcs = &simpledrm_mode_config_funcs;

        /* Primary plane */

        nformats = drm_sysfb_build_fourcc_list(dev, &format->format, 1,
                                               sdev->formats, ARRAY_SIZE(sdev->formats));

        primary_plane = &sdev->primary_plane;
        ret = drm_universal_plane_init(dev, primary_plane, 0, &simpledrm_primary_plane_funcs,
                                       sdev->formats, nformats,
                                       simpledrm_primary_plane_format_modifiers,
                                       DRM_PLANE_TYPE_PRIMARY, NULL);
        if (ret)
                return ERR_PTR(ret);
        drm_plane_helper_add(primary_plane, &simpledrm_primary_plane_helper_funcs);
        drm_plane_enable_fb_damage_clips(primary_plane);

        /* CRTC */

        crtc = &sdev->crtc;
        ret = drm_crtc_init_with_planes(dev, crtc, primary_plane, NULL,
                                        &simpledrm_crtc_funcs, NULL);
        if (ret)
                return ERR_PTR(ret);
        drm_crtc_helper_add(crtc, &simpledrm_crtc_helper_funcs);

        /* Encoder */

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

        /* Connector */

        connector = &sdev->connector;
        ret = drm_connector_init(dev, connector, &simpledrm_connector_funcs,
                                 DRM_MODE_CONNECTOR_Unknown);
        if (ret)
                return ERR_PTR(ret);
        drm_connector_helper_add(connector, &simpledrm_connector_helper_funcs);
        drm_connector_set_panel_orientation_with_quirk(connector,
                                                       DRM_MODE_PANEL_ORIENTATION_UNKNOWN,
                                                       width, height);

        ret = drm_connector_attach_encoder(connector, encoder);
        if (ret)
                return ERR_PTR(ret);

        drm_mode_config_reset(dev);

        return sdev;
}

/*
 * DRM driver
 */

DEFINE_DRM_GEM_FOPS(simpledrm_fops);

static struct drm_driver simpledrm_driver = {
        DRM_GEM_SHMEM_DRIVER_OPS,
        DRM_FBDEV_SHMEM_DRIVER_OPS,
        .name                   = DRIVER_NAME,
        .desc                   = DRIVER_DESC,
        .major                  = DRIVER_MAJOR,
        .minor                  = DRIVER_MINOR,
        .driver_features        = DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
        .fops                   = &simpledrm_fops,
};

/*
 * Platform driver
 */

static int simpledrm_probe(struct platform_device *pdev)
{
        struct simpledrm_device *sdev;
        struct drm_sysfb_device *sysfb;
        struct drm_device *dev;
        int ret;

        sdev = simpledrm_device_create(&simpledrm_driver, pdev);
        if (IS_ERR(sdev))
                return PTR_ERR(sdev);
        sysfb = &sdev->sysfb;
        dev = &sysfb->dev;

        ret = drm_dev_register(dev, 0);
        if (ret)
                return ret;

        drm_client_setup(dev, sdev->sysfb.fb_format);

        return 0;
}

static void simpledrm_remove(struct platform_device *pdev)
{
        struct simpledrm_device *sdev = platform_get_drvdata(pdev);
        struct drm_device *dev = &sdev->sysfb.dev;

        drm_dev_unplug(dev);
}

static const struct of_device_id simpledrm_of_match_table[] = {
        { .compatible = "simple-framebuffer", },
        { },
};
MODULE_DEVICE_TABLE(of, simpledrm_of_match_table);

static struct platform_driver simpledrm_platform_driver = {
        .driver = {
                .name = "simple-framebuffer", /* connect to sysfb */
                .of_match_table = simpledrm_of_match_table,
        },
        .probe = simpledrm_probe,
        .remove = simpledrm_remove,
};

module_platform_driver(simpledrm_platform_driver);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL v2");