[PATCH v3 2/2] drm/imx/lcdc: Implement DRM driver for imx21
Uwe Kleine-König
u.kleine-koenig at pengutronix.de
Fri Dec 16 17:50:06 UTC 2022
From: Marian Cichy <m.cichy at pengutronix.de>
Add support for the LCD Controller found on i.MX21 and i.MX25.
It targets to be a drop in replacement for the imx-fb driver.
Signed-off-by: Marian Cichy <m.cichy at pengutronix.de>
[ukl: Rebase to v6.1, various smaller fixes]
Signed-off-by: Uwe Kleine-König <u.kleine-koenig at pengutronix.de>
---
drivers/gpu/drm/imx/Kconfig | 1 +
drivers/gpu/drm/imx/Makefile | 1 +
drivers/gpu/drm/imx/lcdc/imx-lcdc.c | 587 ++++++++++++++++++++++++++++
3 files changed, 589 insertions(+)
create mode 100644 drivers/gpu/drm/imx/lcdc/imx-lcdc.c
diff --git a/drivers/gpu/drm/imx/Kconfig b/drivers/gpu/drm/imx/Kconfig
index e5749927fd6c..03535a15dd8f 100644
--- a/drivers/gpu/drm/imx/Kconfig
+++ b/drivers/gpu/drm/imx/Kconfig
@@ -2,3 +2,4 @@
source "drivers/gpu/drm/imx/dcss/Kconfig"
source "drivers/gpu/drm/imx/ipuv3/Kconfig"
+source "drivers/gpu/drm/imx/lcdc/Kconfig"
diff --git a/drivers/gpu/drm/imx/Makefile b/drivers/gpu/drm/imx/Makefile
index 909622864716..86f38e7c7422 100644
--- a/drivers/gpu/drm/imx/Makefile
+++ b/drivers/gpu/drm/imx/Makefile
@@ -2,3 +2,4 @@
obj-$(CONFIG_DRM_IMX_DCSS) += dcss/
obj-$(CONFIG_DRM_IMX) += ipuv3/
+obj-$(CONFIG_DRM_IMX_LCDC) += lcdc/
diff --git a/drivers/gpu/drm/imx/lcdc/imx-lcdc.c b/drivers/gpu/drm/imx/lcdc/imx-lcdc.c
new file mode 100644
index 000000000000..79fbb7956374
--- /dev/null
+++ b/drivers/gpu/drm/imx/lcdc/imx-lcdc.c
@@ -0,0 +1,587 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// SPDX-FileCopyrightText: 2020 Marian Cichy <M.Cichy at pengutronix.de>
+
+#include <drm/drm_damage_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fb_dma_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_fourcc.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_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+#include <drm/drm_vblank.h>
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+
+#define IMX21LCDC_LSSAR 0x0000 /* LCDC Screen Start Address Register */
+#define IMX21LCDC_LSR 0x0004 /* LCDC Size Register */
+#define IMX21LCDC_LVPWR 0x0008 /* LCDC Virtual Page Width Register */
+#define IMX21LCDC_LCPR 0x000C /* LCDC Cursor Position Register */
+#define IMX21LCDC_LCWHB 0x0010 /* LCDC Cursor Width Height and Blink Register*/
+#define IMX21LCDC_LCCMR 0x0014 /* LCDC Color Cursor Mapping Register */
+#define IMX21LCDC_LPCR 0x0018 /* LCDC Panel Configuration Register */
+#define IMX21LCDC_LHCR 0x001C /* LCDC Horizontal Configuration Register */
+#define IMX21LCDC_LVCR 0x0020 /* LCDC Vertical Configuration Register */
+#define IMX21LCDC_LPOR 0x0024 /* LCDC Panning Offset Register */
+#define IMX21LCDC_LSCR 0x0028 /* LCDC Sharp Configuration Register */
+#define IMX21LCDC_LPCCR 0x002C /* LCDC PWM Contrast Control Register */
+#define IMX21LCDC_LDCR 0x0030 /* LCDC DMA Control Register */
+#define IMX21LCDC_LRMCR 0x0034 /* LCDC Refresh Mode Control Register */
+#define IMX21LCDC_LICR 0x0038 /* LCDC Interrupt Configuration Register */
+#define IMX21LCDC_LIER 0x003C /* LCDC Interrupt Enable Register */
+#define IMX21LCDC_LISR 0x0040 /* LCDC Interrupt Status Register */
+#define IMX21LCDC_LGWSAR 0x0050 /* LCDC Graphic Window Start Address Register */
+#define IMX21LCDC_LGWSR 0x0054 /* LCDC Graph Window Size Register */
+#define IMX21LCDC_LGWVPWR 0x0058 /* LCDC Graphic Window Virtual Page Width Register */
+#define IMX21LCDC_LGWPOR 0x005C /* LCDC Graphic Window Panning Offset Register */
+#define IMX21LCDC_LGWPR 0x0060 /* LCDC Graphic Window Position Register */
+#define IMX21LCDC_LGWCR 0x0064 /* LCDC Graphic Window Control Register */
+#define IMX21LCDC_LGWDCR 0x0068 /* LCDC Graphic Window DMA Control Register */
+#define IMX21LCDC_LAUSCR 0x0080 /* LCDC AUS Mode Control Register */
+#define IMX21LCDC_LAUSCCR 0x0084 /* LCDC AUS Mode Cursor Control Register */
+#define IMX21LCDC_BGLUT 0x0800 /* Background Lookup Table */
+#define IMX21LCDC_GWLUT 0x0C00 /* Graphic Window Lookup Table */
+
+#define IMX21LCDC_LCPR_CC0 BIT(30) /* Cursor Control Bit 0 */
+#define IMX21LCDC_LCPR_CC1 BIT(31) /* Cursor Control Bit 1 */
+
+/* Values HSYNC, VSYNC and Framesize Register */
+#define IMX21LCDC_LHCR_H_WIDTH(val) (FIELD_PREP(GENMASK(31, 26), (val)))
+#define IMX21LCDC_LHCR_H_BPORCH(val) (FIELD_PREP(GENMASK(7, 0), (val)))
+#define IMX21LCDC_LHCR_H_FPORCH(val) (FIELD_PREP(GENMASK(15, 8), (val)))
+
+#define IMX21LCDC_LVCR_V_WIDTH(val) (FIELD_PREP(GENMASK(31, 26), (val)))
+#define IMX21LCDC_LVCR_V_BPORCH(val) (FIELD_PREP(GENMASK(7, 0), (val)))
+#define IMX21LCDC_LVCR_V_FPORCH(val) (FIELD_PREP(GENMASK(15, 8), (val)))
+
+#define IMX21LCDC_FRAME_WIDTH(val) (((val) / 16) << 20)
+#define IMX21LCDC_FRAME_HEIGHT(val) (val)
+
+/* Values for LPCR Register */
+#define IMX21LCDC_PCD(val) (FIELD_PREP(GENMASK(5, 0), --(val)))
+#define IMX21LCDC_SHARP(val) (FIELD_PREP(GENMASK(6, 6), (val)))
+#define IMX21LCDC_SCLKSEL(val) (FIELD_PREP(GENMASK(7, 7), (val)))
+#define IMX21LCDC_ACD(val) (FIELD_PREP(GENMASK(14, 8), (val)))
+#define IMX21LCDC_ACDSEL(val) (FIELD_PREP(GENMASK(15, 15), (val)))
+#define IMX21LCDC_REV_VS(val) (FIELD_PREP(GENMASK(16, 16), (val)))
+#define IMX21LCDC_SWAP_SEL(val) (FIELD_PREP(GENMASK(17, 17), (val)))
+#define IMX21LCDC_END_SEL(val) (FIELD_PREP(GENMASK(18, 18), (val)))
+#define IMX21LCDC_SCLKIDLE(val) (FIELD_PREP(GENMASK(19, 19), (val)))
+#define IMX21LCDC_OEPOL(val) (FIELD_PREP(GENMASK(20, 20), (val)))
+#define IMX21LCDC_CLKPOL(val) (FIELD_PREP(GENMASK(21, 21), (val)))
+#define IMX21LCDC_LPPOL(val) (FIELD_PREP(GENMASK(22, 22), (val)))
+#define IMX21LCDC_FLMPOL(val) (FIELD_PREP(GENMASK(23, 23), (val)))
+#define IMX21LCDC_PIXPOL(val) (FIELD_PREP(GENMASK(24, 24), (val)))
+#define IMX21LCDC_BPIX(val) (FIELD_PREP(GENMASK(27, 25), (val)))
+#define IMX21LCDC_PBSIZ(val) (FIELD_PREP(GENMASK(29, 28), (val)))
+#define IMX21LCDC_COLOR(val) (FIELD_PREP(GENMASK(30, 30), (val)))
+#define IMX21LCDC_TFT(val) (FIELD_PREP(GENMASK(31, 31), (val)))
+
+#define INTR_EOF BIT(1) /* VBLANK Interrupt Bit */
+
+#define BPP_RGB565 0x05
+
+#define LCDC_MIN_XRES 64
+#define LCDC_MIN_YRES 64
+
+#define LCDC_MAX_XRES 1024
+#define LCDC_MAX_YRES 1024
+
+struct imx_lcdc {
+ struct drm_device drm;
+ struct drm_simple_display_pipe pipe;
+ const struct drm_display_mode *mode;
+ struct drm_connector connector;
+ struct drm_panel *panel;
+ struct drm_bridge *bridge;
+ void __iomem *base;
+
+ struct clk *clk_ipg;
+ struct clk *clk_ahb;
+ struct clk *clk_per;
+};
+
+static const u32 imx_lcdc_formats[] = {
+ DRM_FORMAT_RGB565,
+};
+
+static inline struct imx_lcdc *imx_lcdc_from_drmdev(struct drm_device *drm)
+{
+ return container_of(drm, struct imx_lcdc, drm);
+}
+
+static unsigned int imx_lcdc_get_format(unsigned int drm_format)
+{
+ unsigned int bpp;
+
+ switch (drm_format) {
+ default:
+ DRM_WARN("Format not supported - fallback to RGB565\n");
+ fallthrough;
+ case DRM_FORMAT_RGB565:
+ bpp = BPP_RGB565;
+ break;
+ }
+
+ return bpp;
+}
+
+static int imx_lcdc_connector_get_modes(struct drm_connector *connector)
+{
+ struct imx_lcdc *lcdc = imx_lcdc_from_drmdev(connector->dev);
+
+ if (lcdc->panel)
+ return drm_panel_get_modes(lcdc->panel, connector);
+
+ return 0;
+}
+
+static const struct drm_connector_helper_funcs imx_lcdc_connector_hfuncs = {
+ .get_modes = imx_lcdc_connector_get_modes,
+};
+
+static const struct drm_connector_funcs imx_lcdc_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 void imx_lcdc_update_hw_registers(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *old_state,
+ bool mode_set)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_plane_state *new_state = pipe->plane.state;
+ struct drm_framebuffer *fb = new_state->fb;
+ struct imx_lcdc *lcdc = imx_lcdc_from_drmdev(pipe->crtc.dev);
+ unsigned int bpp;
+ unsigned int lvcr; /* LVCR-Register value */
+ unsigned int lhcr; /* LHCR-Register value */
+ unsigned int framesize;
+ dma_addr_t addr;
+
+ addr = drm_fb_dma_get_gem_addr(fb, new_state, 0);
+ /* The LSSAR register specifies the LCD screen start address (SSA). */
+ writel(addr, lcdc->base + IMX21LCDC_LSSAR);
+
+ if (!mode_set)
+ return;
+
+ /* Disable PER clock to make register write possible */
+ if (old_state && old_state->crtc && old_state->crtc->enabled)
+ clk_disable_unprepare(lcdc->clk_per);
+
+ /* Framesize */
+ framesize = IMX21LCDC_FRAME_WIDTH(crtc->mode.hdisplay);
+ framesize |= IMX21LCDC_FRAME_HEIGHT(crtc->mode.vdisplay);
+ writel(framesize, lcdc->base + IMX21LCDC_LSR);
+
+ /* HSYNC */
+ lhcr = IMX21LCDC_LHCR_H_FPORCH(crtc->mode.hsync_start - crtc->mode.hdisplay - 1);
+ lhcr |= IMX21LCDC_LHCR_H_WIDTH(crtc->mode.hsync_end - crtc->mode.hsync_start - 1);
+ lhcr |= IMX21LCDC_LHCR_H_BPORCH(crtc->mode.htotal - crtc->mode.hsync_end - 3);
+ writel(lhcr, lcdc->base + IMX21LCDC_LHCR);
+
+ /* VSYNC */
+ lvcr = IMX21LCDC_LVCR_V_FPORCH(crtc->mode.vsync_start - crtc->mode.vdisplay);
+ lvcr |= IMX21LCDC_LVCR_V_WIDTH(crtc->mode.vsync_end - crtc->mode.vsync_start);
+ lvcr |= IMX21LCDC_LVCR_V_BPORCH(crtc->mode.vtotal - crtc->mode.vsync_end);
+ writel(lvcr, lcdc->base + IMX21LCDC_LVCR);
+
+ bpp = imx_lcdc_get_format(fb->format->format);
+ writel(readl(lcdc->base + IMX21LCDC_LPCR) | IMX21LCDC_BPIX(bpp),
+ lcdc->base + IMX21LCDC_LPCR);
+
+ /* Virtual Page Width */
+ writel(new_state->fb->pitches[0] / 4, lcdc->base + IMX21LCDC_LVPWR);
+
+ /* Enable PER clock */
+ if (new_state->crtc->enabled)
+ clk_prepare_enable(lcdc->clk_per);
+}
+
+static void imx_lcdc_pipe_enable(struct drm_simple_display_pipe *pipe,
+ struct drm_crtc_state *crtc_state,
+ struct drm_plane_state *plane_state)
+{
+ int ret;
+ int clk_div;
+ int bpp;
+ struct imx_lcdc *lcdc = imx_lcdc_from_drmdev(pipe->crtc.dev);
+ struct drm_display_mode *mode = &pipe->crtc.mode;
+ struct drm_display_info *disp_info = &pipe->connector->display_info;
+ const int hsync_pol = (mode->flags & DRM_MODE_FLAG_PHSYNC) ? 0 : 1;
+ const int vsync_pol = (mode->flags & DRM_MODE_FLAG_PVSYNC) ? 0 : 1;
+ const int data_enable_pol =
+ (disp_info->bus_flags & DRM_BUS_FLAG_DE_HIGH) ? 0 : 1;
+ const int clk_pol =
+ (disp_info->bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE) ? 0 : 1;
+
+ ret = drm_panel_prepare(lcdc->panel);
+ if (ret) {
+ dev_err(pipe->crtc.dev->dev, "Cannot prepare panel: %pe\n", ERR_PTR(ret));
+ return;
+ }
+
+ clk_div = DIV_ROUND_CLOSEST_ULL(clk_get_rate(lcdc->clk_per),
+ mode->clock * 1000);
+ bpp = imx_lcdc_get_format(plane_state->fb->format->format);
+
+ writel(IMX21LCDC_PCD(clk_div) | IMX21LCDC_LPPOL(hsync_pol) | IMX21LCDC_FLMPOL(vsync_pol) |
+ IMX21LCDC_OEPOL(data_enable_pol) | IMX21LCDC_TFT(1) | IMX21LCDC_COLOR(1) |
+ IMX21LCDC_PBSIZ(3) | IMX21LCDC_BPIX(bpp) | IMX21LCDC_SCLKSEL(1) |
+ IMX21LCDC_PIXPOL(0) | IMX21LCDC_CLKPOL(clk_pol),
+ lcdc->base + IMX21LCDC_LPCR);
+
+ /* 0px panning offset */
+ writel(0x00000000, lcdc->base + IMX21LCDC_LPOR);
+
+ /* disable hardware cursor */
+ writel(readl(lcdc->base + IMX21LCDC_LCPR) & ~(IMX21LCDC_LCPR_CC0 | IMX21LCDC_LCPR_CC1),
+ lcdc->base + IMX21LCDC_LCPR);
+
+ ret = clk_prepare_enable(lcdc->clk_ipg);
+ if (ret) {
+ dev_err(pipe->crtc.dev->dev, "Cannot enable ipg clock: %pe\n", ERR_PTR(ret));
+ return;
+ }
+ ret = clk_prepare_enable(lcdc->clk_ahb);
+ if (ret) {
+ dev_err(pipe->crtc.dev->dev, "Cannot enable ahb clock: %pe\n", ERR_PTR(ret));
+ goto err_enable_clk_ahb;
+ }
+
+ imx_lcdc_update_hw_registers(pipe, NULL, true);
+ ret = drm_panel_enable(lcdc->panel);
+ if (ret) {
+ dev_err(pipe->crtc.dev->dev, "Cannot enable panel: %pe\n", ERR_PTR(ret));
+
+ clk_disable_unprepare(lcdc->clk_ahb);
+err_enable_clk_ahb:
+
+ clk_disable_unprepare(lcdc->clk_ipg);
+
+ return;
+ }
+
+ /* Enable VBLANK Interrupt */
+ writel(INTR_EOF, lcdc->base + IMX21LCDC_LIER);
+}
+
+static void imx_lcdc_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+ struct imx_lcdc *lcdc = imx_lcdc_from_drmdev(pipe->crtc.dev);
+ struct drm_panel *panel = lcdc->panel;
+ struct drm_crtc *crtc = &lcdc->pipe.crtc;
+ struct drm_pending_vblank_event *event;
+
+ drm_panel_disable(panel);
+
+ clk_disable_unprepare(lcdc->clk_ahb);
+ clk_disable_unprepare(lcdc->clk_ipg);
+
+ if (pipe->crtc.enabled)
+ clk_disable_unprepare(lcdc->clk_per);
+
+ drm_panel_unprepare(panel);
+
+ spin_lock_irq(&lcdc->drm.event_lock);
+ event = crtc->state->event;
+ if (event) {
+ crtc->state->event = NULL;
+ drm_crtc_send_vblank_event(crtc, event);
+ }
+ spin_unlock_irq(&lcdc->drm.event_lock);
+
+ /* Disable VBLANK Interrupt */
+ writel(0, lcdc->base + IMX21LCDC_LIER);
+}
+
+static int imx_lcdc_pipe_check(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *plane_state,
+ struct drm_crtc_state *crtc_state)
+{
+ const struct drm_display_mode *mode = &crtc_state->mode;
+ const struct drm_display_mode *old_mode = &pipe->crtc.state->mode;
+
+ if (mode->hdisplay < LCDC_MIN_XRES || mode->hdisplay > LCDC_MAX_XRES ||
+ mode->vdisplay < LCDC_MIN_YRES || mode->vdisplay > LCDC_MAX_YRES ||
+ mode->hdisplay & 0x10) { /* must be multiple of 16 */
+ drm_err(pipe->crtc.dev, "unsupported display mode (%u x %u)\n",
+ mode->hdisplay, mode->vdisplay);
+ return -EINVAL;
+ }
+
+ crtc_state->mode_changed =
+ old_mode->hdisplay != mode->hdisplay ||
+ old_mode->vdisplay != mode->vdisplay;
+
+ return 0;
+}
+
+static void imx_lcdc_pipe_update(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *old_state)
+{
+ struct drm_crtc *crtc = &pipe->crtc;
+ struct drm_pending_vblank_event *event = crtc->state->event;
+ struct drm_plane_state *new_state = pipe->plane.state;
+ struct drm_framebuffer *fb = new_state->fb;
+ struct drm_framebuffer *old_fb = old_state->fb;
+ struct drm_crtc *old_crtc = old_state->crtc;
+ bool mode_changed = false;
+
+ if (old_fb && old_fb->format != fb->format)
+ mode_changed = true;
+ else if (old_crtc != crtc)
+ mode_changed = true;
+
+ imx_lcdc_update_hw_registers(pipe, old_state, mode_changed);
+
+ if (event) {
+ crtc->state->event = NULL;
+
+ spin_lock_irq(&crtc->dev->event_lock);
+
+ if (crtc->state->active && drm_crtc_vblank_get(crtc) == 0)
+ drm_crtc_arm_vblank_event(crtc, event);
+ else
+ drm_crtc_send_vblank_event(crtc, event);
+
+ spin_unlock_irq(&crtc->dev->event_lock);
+ }
+}
+
+static const struct drm_simple_display_pipe_funcs imx_lcdc_pipe_funcs = {
+ .enable = imx_lcdc_pipe_enable,
+ .disable = imx_lcdc_pipe_disable,
+ .check = imx_lcdc_pipe_check,
+ .update = imx_lcdc_pipe_update,
+ .prepare_fb = drm_gem_simple_display_pipe_prepare_fb,
+};
+
+static const struct drm_mode_config_funcs imx_lcdc_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_mode_config_helper_funcs imx_lcdc_mode_config_helpers = {
+ .atomic_commit_tail = drm_atomic_helper_commit_tail_rpm,
+};
+
+static void imx_lcdc_release(struct drm_device *drm)
+{
+ struct imx_lcdc *lcdc = imx_lcdc_from_drmdev(drm);
+
+ drm_kms_helper_poll_fini(drm);
+ kfree(lcdc);
+}
+
+DEFINE_DRM_GEM_DMA_FOPS(imx_lcdc_drm_fops);
+
+static struct drm_driver imx_lcdc_drm_driver = {
+ .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
+ .fops = &imx_lcdc_drm_fops,
+ DRM_GEM_DMA_DRIVER_OPS_VMAP,
+ .release = imx_lcdc_release,
+ .name = "imx-lcdc",
+ .desc = "i.MX LCDC driver",
+ .date = "20200716",
+};
+
+static const struct of_device_id imx_lcdc_of_dev_id[] = {
+ {
+ .compatible = "fsl,imx21-lcdc",
+ },
+ {
+ .compatible = "fsl,imx25-lcdc",
+ },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_lcdc_of_dev_id);
+
+static irqreturn_t imx_lcdc_irq_handler(int irq, void *arg)
+{
+ struct imx_lcdc *lcdc = arg;
+ struct drm_crtc *crtc = &lcdc->pipe.crtc;
+ unsigned int status;
+
+ status = readl(lcdc->base + IMX21LCDC_LISR);
+
+ if (status & INTR_EOF) {
+ drm_crtc_handle_vblank(crtc);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static int imx_lcdc_probe(struct platform_device *pdev)
+{
+ struct imx_lcdc *lcdc;
+ struct drm_device *drm;
+ int irq;
+ int ret;
+ struct device *dev = &pdev->dev;
+
+ lcdc = devm_drm_dev_alloc(dev, &imx_lcdc_drm_driver,
+ struct imx_lcdc, drm);
+ if (!lcdc)
+ return -ENOMEM;
+
+ drm = &lcdc->drm;
+
+ lcdc->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(lcdc->base))
+ return dev_err_probe(dev, PTR_ERR(lcdc->base), "Cannot get IO memory\n");
+
+ /* Panel */
+ ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &lcdc->panel, &lcdc->bridge);
+ if (ret)
+ return dev_err_probe(dev, ret, "Failed to find panel or bridge\n");
+
+ /* Get Clocks */
+ lcdc->clk_ipg = devm_clk_get(dev, "ipg");
+ if (IS_ERR(lcdc->clk_ipg))
+ return dev_err_probe(dev, PTR_ERR(lcdc->clk_ipg), "Failed to get %s clk\n", "ipg");
+
+ lcdc->clk_ahb = devm_clk_get(dev, "ahb");
+ if (IS_ERR(lcdc->clk_ahb))
+ return dev_err_probe(dev, PTR_ERR(lcdc->clk_ahb), "Failed to get %s clk\n", "ahb");
+
+ lcdc->clk_per = devm_clk_get(dev, "per");
+ if (IS_ERR(lcdc->clk_per))
+ return dev_err_probe(dev, PTR_ERR(lcdc->clk_per), "Failed to get %s clk\n", "per");
+
+ ret = dma_set_mask_and_coherent(drm->dev, DMA_BIT_MASK(32));
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot set DMA Mask\n");
+
+ /* Modeset init */
+ ret = drmm_mode_config_init(drm);
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot initialize mode configuration structure\n");
+
+ /* CRTC, Plane, Encoder */
+ ret = drm_simple_display_pipe_init(drm, &lcdc->pipe, &imx_lcdc_pipe_funcs, imx_lcdc_formats,
+ ARRAY_SIZE(imx_lcdc_formats), NULL, &lcdc->connector);
+ if (ret < 0)
+ return dev_err_probe(drm->dev, ret, "Cannot setup simple display pipe\n");
+
+ ret = drm_vblank_init(drm, drm->mode_config.num_crtc);
+ if (ret < 0)
+ return dev_err_probe(drm->dev, ret, "Failed to initialize vblank\n");
+
+ if (lcdc->bridge) {
+ ret = drm_simple_display_pipe_attach_bridge(&lcdc->pipe,
+ lcdc->bridge);
+ if (ret)
+ return dev_err_probe(drm->dev, ret, "Cannot connect bridge\n");
+ }
+
+ /* Connector */
+ drm_connector_helper_add(&lcdc->connector, &imx_lcdc_connector_hfuncs);
+ ret = drm_connector_init(drm, &lcdc->connector, &imx_lcdc_connector_funcs,
+ DRM_MODE_CONNECTOR_DPI);
+ if (ret)
+ return dev_err_probe(drm->dev, ret, "Cannot initialize connector\n");
+
+ /*
+ * The LCDC controller does not have an enable bit. The
+ * controller starts directly when the clocks are enabled.
+ * If the clocks are enabled when the controller is not yet
+ * programmed with proper register values (enabled at the
+ * bootloader, for example) then it just goes into some undefined
+ * state.
+ * To avoid this issue, let's enable and disable LCDC IPG,
+ * PER and AHB clock so that we force some kind of 'reset'
+ * to the LCDC block.
+ */
+
+ ret = clk_prepare_enable(lcdc->clk_ipg);
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot enable ipg clock\n");
+ clk_disable_unprepare(lcdc->clk_ipg);
+
+ ret = clk_prepare_enable(lcdc->clk_per);
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot enable per clock\n");
+ clk_disable_unprepare(lcdc->clk_per);
+
+ ret = clk_prepare_enable(lcdc->clk_ahb);
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot enable ahb clock\n");
+ clk_disable_unprepare(lcdc->clk_ahb);
+
+ drm->mode_config.min_width = LCDC_MIN_XRES;
+ drm->mode_config.max_width = LCDC_MAX_XRES;
+ drm->mode_config.min_height = LCDC_MIN_YRES;
+ drm->mode_config.max_height = LCDC_MAX_YRES;
+ drm->mode_config.preferred_depth = 16;
+ drm->mode_config.funcs = &imx_lcdc_mode_config_funcs;
+ drm->mode_config.helper_private = &imx_lcdc_mode_config_helpers;
+
+ drm_mode_config_reset(drm);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ ret = irq;
+ return ret;
+ }
+
+ ret = devm_request_irq(dev, irq, imx_lcdc_irq_handler, 0, "imx-lcdc", lcdc);
+ if (ret < 0)
+ return dev_err_probe(drm->dev, ret, "Failed to install IRQ handler\n");
+
+ platform_set_drvdata(pdev, drm);
+
+ ret = drm_dev_register(&lcdc->drm, 0);
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot register device\n");
+
+ drm_fbdev_generic_setup(drm, 0);
+
+ return 0;
+}
+
+static int imx_lcdc_remove(struct platform_device *pdev)
+{
+ struct drm_device *drm = platform_get_drvdata(pdev);
+
+ drm_dev_unregister(drm);
+ drm_atomic_helper_shutdown(drm);
+
+ return 0;
+}
+
+static void imx_lcdc_shutdown(struct platform_device *pdev)
+{
+ drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
+}
+
+static struct platform_driver imx_lcdc_driver = {
+ .driver = {
+ .name = "imx-lcdc",
+ .of_match_table = imx_lcdc_of_dev_id,
+ },
+ .probe = imx_lcdc_probe,
+ .remove = imx_lcdc_remove,
+ .shutdown = imx_lcdc_shutdown,
+};
+module_platform_driver(imx_lcdc_driver);
+
+MODULE_AUTHOR("Marian Cichy <M.Cichy at pengutronix.de>");
+MODULE_DESCRIPTION("Freescale i.MX LCDC driver");
+MODULE_LICENSE("GPL");
--
2.38.1
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