[PATCH v5 2/2] drm/imx/lcdc: Implement DRM driver for imx25
Uwe Kleine-König
u.kleine-koenig at pengutronix.de
Fri Feb 10 10:00:14 PST 2023
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 a newer kernel version, various smaller fixes and
improvements]
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/Kconfig | 7 +
drivers/gpu/drm/imx/lcdc/Makefile | 1 +
drivers/gpu/drm/imx/lcdc/imx-lcdc.c | 553 ++++++++++++++++++++++++++++
5 files changed, 563 insertions(+)
create mode 100644 drivers/gpu/drm/imx/lcdc/Kconfig
create mode 100644 drivers/gpu/drm/imx/lcdc/Makefile
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-$(CONFIG_DRM_IMX_LCDC) += lcdc/
diff --git a/drivers/gpu/drm/imx/lcdc/Kconfig b/drivers/gpu/drm/imx/lcdc/Kconfig
new file mode 100644
index 000000000000..7e57922bbd9d
--- /dev/null
+++ b/drivers/gpu/drm/imx/lcdc/Kconfig
@@ -0,0 +1,7 @@
+config DRM_IMX_LCDC
+ tristate "Freescale i.MX LCDC displays"
+ depends on DRM && (ARCH_MXC || COMPILE_TEST)
+ select DRM_GEM_DMA_HELPER
+ select DRM_KMS_HELPER
+ help
+ Found on i.MX1, i.MX21, i.MX25 and i.MX27.
diff --git a/drivers/gpu/drm/imx/lcdc/Makefile b/drivers/gpu/drm/imx/lcdc/Makefile
new file mode 100644
index 000000000000..e84daa432c2e
--- /dev/null
+++ b/drivers/gpu/drm/imx/lcdc/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_DRM_IMX_LCDC) += imx-lcdc.o
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..c2197fc50306
--- /dev/null
+++ b/drivers/gpu/drm/imx/lcdc/imx-lcdc.c
@@ -0,0 +1,553 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// SPDX-FileCopyrightText: 2020 Marian Cichy <M.Cichy at pengutronix.de>
+
+#include <drm/drm_bridge_connector.h>
+#include <drm/drm_damage_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fbdev_generic.h>
+#include <drm/drm_fb_dma_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_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_HWIDTH GENMASK(31, 26)
+#define IMX21LCDC_LHCR_HFPORCH GENMASK(15, 8) /* H_WAIT_1 in the i.MX25 Reference manual */
+#define IMX21LCDC_LHCR_HBPORCH GENMASK(7, 0) /* H_WAIT_2 in the i.MX25 Reference manual */
+
+#define IMX21LCDC_LVCR_VWIDTH GENMASK(31, 26)
+#define IMX21LCDC_LVCR_VFPORCH GENMASK(15, 8) /* V_WAIT_1 in the i.MX25 Reference manual */
+#define IMX21LCDC_LVCR_VBPORCH GENMASK(7, 0) /* V_WAIT_2 in the i.MX25 Reference manual */
+
+#define IMX21LCDC_LSR_XMAX GENMASK(25, 20)
+#define IMX21LCDC_LSR_YMAX GENMASK(9, 0)
+
+/* Values for LPCR Register */
+#define IMX21LCDC_LPCR_PCD GENMASK(5, 0)
+#define IMX21LCDC_LPCR_SHARP BIT(6)
+#define IMX21LCDC_LPCR_SCLKSEL BIT(7)
+#define IMX21LCDC_LPCR_ACD GENMASK(14, 8)
+#define IMX21LCDC_LPCR_ACDSEL BIT(15)
+#define IMX21LCDC_LPCR_REV_VS BIT(16)
+#define IMX21LCDC_LPCR_SWAP_SEL BIT(17)
+#define IMX21LCDC_LPCR_END_SEL BIT(18)
+#define IMX21LCDC_LPCR_SCLKIDLE BIT(19)
+#define IMX21LCDC_LPCR_OEPOL BIT(20)
+#define IMX21LCDC_LPCR_CLKPOL BIT(21)
+#define IMX21LCDC_LPCR_LPPOL BIT(22)
+#define IMX21LCDC_LPCR_FLMPOL BIT(23)
+#define IMX21LCDC_LPCR_PIXPOL BIT(24)
+#define IMX21LCDC_LPCR_BPIX GENMASK(27, 25)
+#define IMX21LCDC_LPCR_PBSIZ GENMASK(29, 28)
+#define IMX21LCDC_LPCR_COLOR BIT(30)
+#define IMX21LCDC_LPCR_TFT BIT(31)
+
+#define INTR_EOF BIT(1) /* VBLANK Interrupt Bit */
+
+#define BPP_RGB565 0x05
+#define BPP_XRGB8888 0x07
+
+#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_bridge *bridge;
+ struct drm_connector *connector;
+ void __iomem *base;
+
+ struct clk *clk_ipg;
+ struct clk *clk_ahb;
+ struct clk *clk_per;
+};
+
+static const u32 imx_lcdc_formats[] = {
+ DRM_FORMAT_RGB565, DRM_FORMAT_XRGB8888,
+};
+
+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 XRGB8888\n");
+ fallthrough;
+
+ case DRM_FORMAT_XRGB8888:
+ bpp = BPP_XRGB8888;
+ break;
+
+ case DRM_FORMAT_RGB565:
+ bpp = BPP_RGB565;
+ break;
+ }
+
+ return bpp;
+}
+
+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);
+ u32 lpcr, lvcr, lhcr;
+ u32 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 = FIELD_PREP(IMX21LCDC_LSR_XMAX, crtc->mode.hdisplay >> 4) |
+ FIELD_PREP(IMX21LCDC_LSR_YMAX, crtc->mode.vdisplay);
+ writel(framesize, lcdc->base + IMX21LCDC_LSR);
+
+ /* HSYNC */
+ lhcr = FIELD_PREP(IMX21LCDC_LHCR_HFPORCH, crtc->mode.hsync_start - crtc->mode.hdisplay - 1) |
+ FIELD_PREP(IMX21LCDC_LHCR_HWIDTH, crtc->mode.hsync_end - crtc->mode.hsync_start - 1) |
+ FIELD_PREP(IMX21LCDC_LHCR_HBPORCH, crtc->mode.htotal - crtc->mode.hsync_end - 3);
+ writel(lhcr, lcdc->base + IMX21LCDC_LHCR);
+
+ /* VSYNC */
+ lvcr = FIELD_PREP(IMX21LCDC_LVCR_VFPORCH, crtc->mode.vsync_start - crtc->mode.vdisplay) |
+ FIELD_PREP(IMX21LCDC_LVCR_VWIDTH, crtc->mode.vsync_end - crtc->mode.vsync_start) |
+ FIELD_PREP(IMX21LCDC_LVCR_VBPORCH, crtc->mode.vtotal - crtc->mode.vsync_end);
+ writel(lvcr, lcdc->base + IMX21LCDC_LVCR);
+
+ lpcr = readl(lcdc->base + IMX21LCDC_LPCR);
+ lpcr &= ~IMX21LCDC_LPCR_BPIX;
+ lpcr |= FIELD_PREP(IMX21LCDC_LPCR_BPIX, imx_lcdc_get_format(fb->format->format));
+ writel(lpcr, 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 = &lcdc->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;
+
+ 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(FIELD_PREP(IMX21LCDC_LPCR_PCD, clk_div - 1) |
+ FIELD_PREP(IMX21LCDC_LPCR_LPPOL, hsync_pol) |
+ FIELD_PREP(IMX21LCDC_LPCR_FLMPOL, vsync_pol) |
+ FIELD_PREP(IMX21LCDC_LPCR_OEPOL, data_enable_pol) |
+ FIELD_PREP(IMX21LCDC_LPCR_TFT, 1) |
+ FIELD_PREP(IMX21LCDC_LPCR_COLOR, 1) |
+ FIELD_PREP(IMX21LCDC_LPCR_PBSIZ, 3) |
+ FIELD_PREP(IMX21LCDC_LPCR_BPIX, bpp) |
+ FIELD_PREP(IMX21LCDC_LPCR_SCLKSEL, 1) |
+ FIELD_PREP(IMX21LCDC_LPCR_PIXPOL, 0) |
+ FIELD_PREP(IMX21LCDC_LPCR_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));
+
+ clk_disable_unprepare(lcdc->clk_ipg);
+
+ return;
+ }
+
+ imx_lcdc_update_hw_registers(pipe, NULL, true);
+
+ /* 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_crtc *crtc = &lcdc->pipe.crtc;
+ struct drm_pending_vblank_event *event;
+
+ clk_disable_unprepare(lcdc->clk_ahb);
+ clk_disable_unprepare(lcdc->clk_ipg);
+
+ if (pipe->crtc.enabled)
+ clk_disable_unprepare(lcdc->clk_per);
+
+ 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,
+};
+
+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");
+
+ lcdc->bridge = devm_drm_of_get_bridge(dev, dev->of_node, 0, 0);
+ if (IS_ERR(lcdc->bridge))
+ return dev_err_probe(dev, PTR_ERR(lcdc->bridge), "Failed to find 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, NULL);
+ 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");
+
+ ret = drm_bridge_attach(&lcdc->pipe.encoder, lcdc->bridge, NULL, DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+ if (ret)
+ return dev_err_probe(drm->dev, ret, "Cannot attach bridge\n");
+
+ lcdc->connector = drm_bridge_connector_init(drm, &lcdc->pipe.encoder);
+ if (IS_ERR(lcdc->connector))
+ return dev_err_probe(drm->dev, PTR_ERR(lcdc->connector), "Cannot init bridge connector\n");
+
+ drm_connector_attach_encoder(lcdc->connector, &lcdc->pipe.encoder);
+
+ /*
+ * 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");
--
2.39.0
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