[PATCH v2 1/3] dt-bindings: Add doc for the ingenic-drm driver

[PATCH v2 1/3] dt-bindings: Add doc for the ingenic-drm driver

[Paul Cercueil]

Add documentation for the devicetree bindings of the DRM driver for the
JZ47xx family of SoCs from Ingenic.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
---

Notes:
    v2: Remove ingenic,panel property.

 .../devicetree/bindings/display/ingenic,drm.txt    | 29 ++++++++++++++++++++++
 1 file changed, 29 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/display/ingenic,drm.txt

diff --git a/Documentation/devicetree/bindings/display/ingenic,drm.txt b/Documentation/devicetree/bindings/display/ingenic,drm.txt
new file mode 100644
index 000000000000..f57a4ae0f7ac
--- /dev/null
+++ b/Documentation/devicetree/bindings/display/ingenic,drm.txt
@@ -0,0 +1,29 @@
+Ingenic JZ47xx DRM driver
+
+Required properties:
+- compatible: one of:
+  * ingenic,jz4740-drm
+  * ingenic,jz4725b-drm
+- reg: LCD registers location and length
+- clocks: LCD pixclock and device clock specifiers.
+	   The device clock is only required on the JZ4740.
+- clock-names: "lcd_pclk" and "lcd"
+- interrupts: Specifies the interrupt line the LCD controller is connected to.
+
+Optional properties:
+- ingenic,lcd-mode: LCD mode to use with the display panel.
+		    See <dt-bindings/display/ingenic,drm.h> for all the
+		    possible values.
+
+Example:
+
+lcd: lcd-controller@13050000 {
+	compatible = "ingenic,jz4725b-drm";
+	reg = <0x13050000 0x1000>;
+
+	interrupt-parent = <&intc>;
+	interrupts = <31>;
+
+	clocks = <&cgu JZ4725B_CLK_LCD>;
+	clock-names = "lcd";
+};
-- 
2.11.0

[PATCH v2 2/3] dt-bindings: Add header for the ingenic-drm driver bindings

[Paul Cercueil]

Add macros that can be used with the ingenic,lcd-mode property in the
devicetree node that corresponds to the ingenic-drm driver.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
---

Notes:
    v2: No change

 include/dt-bindings/display/ingenic,drm.h | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)
 create mode 100644 include/dt-bindings/display/ingenic,drm.h

diff --git a/include/dt-bindings/display/ingenic,drm.h b/include/dt-bindings/display/ingenic,drm.h
new file mode 100644
index 000000000000..20c5399366c1
--- /dev/null
+++ b/include/dt-bindings/display/ingenic,drm.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ *  Ingenic JZ47xx KMS driver
+ *
+ *  Copyright (C) 2019, Paul Cercueil <paul@crapouillou.net>
+ */
+#ifndef __INCLUDE_DT_BINDINGS_DISPLAY_INGENIC_DRM_H__
+#define __INCLUDE_DT_BINDINGS_DISPLAY_INGENIC_DRM_H__
+
+#define JZ_DRM_LCD_GENERIC_16BIT		0
+#define JZ_DRM_LCD_GENERIC_18BIT		16
+
+#define JZ_DRM_LCD_SPECIAL_TFT_1		1
+#define JZ_DRM_LCD_SPECIAL_TFT_2		2
+#define JZ_DRM_LCD_SPECIAL_TFT_3		3
+
+#define JZ_DRM_LCD_NON_INTERLACED_TV_OUT	4
+#define JZ_DRM_LCD_INTERLACED_TV_OUT		6
+
+#define JZ_DRM_LCD_SINGLE_COLOR_STN		8
+#define JZ_DRM_LCD_SINGLE_MONOCHROME_STN	9
+#define JZ_DRM_LCD_DUAL_COLOR_STN		10
+#define JZ_DRM_LCD_DUAL_MONOCHROME_STN		11
+
+#define JZ_LCD_TYPE_8BIT_SERIAL			12
+#define JZ_LCD_TYPE_LCM				13
+
+#endif /* __INCLUDE_DT_BINDINGS_DISPLAY_INGENIC_DRM_H__ */
-- 
2.11.0

[PATCH v2 3/3] DRM: Add KMS driver for the Ingenic JZ47xx SoCs

[Paul Cercueil]

Add a KMS driver for the Ingenic JZ47xx family of SoCs.
This driver is meant to replace the aging jz4740-fb driver.

Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Tested-by: Artur Rojek <contact@artur-rojek.eu>
---

Notes:
    v2: - Remove custom handling of panel. The panel is now discovered using
          the standard API.
        - Lots of small tweaks suggested by upstream

 drivers/gpu/drm/Kconfig               |   2 +
 drivers/gpu/drm/Makefile              |   1 +
 drivers/gpu/drm/ingenic/Kconfig       |  16 +
 drivers/gpu/drm/ingenic/Makefile      |   1 +
 drivers/gpu/drm/ingenic/ingenic-drm.c | 803 ++++++++++++++++++++++++++++++++++
 5 files changed, 823 insertions(+)
 create mode 100644 drivers/gpu/drm/ingenic/Kconfig
 create mode 100644 drivers/gpu/drm/ingenic/Makefile
 create mode 100644 drivers/gpu/drm/ingenic/ingenic-drm.c

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index 5e1bc630b885..b24e1dc1d6e5 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -309,6 +309,8 @@ source "drivers/gpu/drm/sti/Kconfig"
 
 source "drivers/gpu/drm/imx/Kconfig"
 
+source "drivers/gpu/drm/ingenic/Kconfig"
+
 source "drivers/gpu/drm/v3d/Kconfig"
 
 source "drivers/gpu/drm/vc4/Kconfig"
diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
index e630eccb951c..eb63d34b5e18 100644
--- a/drivers/gpu/drm/Makefile
+++ b/drivers/gpu/drm/Makefile
@@ -95,6 +95,7 @@ obj-$(CONFIG_DRM_TEGRA) += tegra/
 obj-$(CONFIG_DRM_STM) += stm/
 obj-$(CONFIG_DRM_STI) += sti/
 obj-$(CONFIG_DRM_IMX) += imx/
+obj-$(CONFIG_DRM_INGENIC) += ingenic/
 obj-$(CONFIG_DRM_MEDIATEK) += mediatek/
 obj-$(CONFIG_DRM_MESON)	+= meson/
 obj-y			+= i2c/
diff --git a/drivers/gpu/drm/ingenic/Kconfig b/drivers/gpu/drm/ingenic/Kconfig
new file mode 100644
index 000000000000..d82c3d37ec9c
--- /dev/null
+++ b/drivers/gpu/drm/ingenic/Kconfig
@@ -0,0 +1,16 @@
+config DRM_INGENIC
+	tristate "DRM Support for Ingenic SoCs"
+	depends on MIPS || COMPILE_TEST
+	depends on DRM
+	depends on CMA
+	depends on OF
+	select DRM_BRIDGE
+	select DRM_PANEL_BRIDGE
+	select DRM_KMS_HELPER
+	select DRM_KMS_CMA_HELPER
+	select DRM_GEM_CMA_HELPER
+	select VT_HW_CONSOLE_BINDING if FRAMEBUFFER_CONSOLE
+	help
+	  Choose this option for DRM support for the Ingenic SoCs.
+
+	  If M is selected the module will be called ingenic-drm.
diff --git a/drivers/gpu/drm/ingenic/Makefile b/drivers/gpu/drm/ingenic/Makefile
new file mode 100644
index 000000000000..11cac42ce0bb
--- /dev/null
+++ b/drivers/gpu/drm/ingenic/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_DRM_INGENIC) += ingenic-drm.o
diff --git a/drivers/gpu/drm/ingenic/ingenic-drm.c b/drivers/gpu/drm/ingenic/ingenic-drm.c
new file mode 100644
index 000000000000..056eed0a0eb2
--- /dev/null
+++ b/drivers/gpu/drm/ingenic/ingenic-drm.c
@@ -0,0 +1,803 @@
+// SPDX-License-Identifier: GPL-2.0
+//
+// Ingenic JZ47xx KMS driver
+//
+// Copyright (C) 2019, Paul Cercueil <paul@crapouillou.net>
+
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_fb_helper.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_irq.h>
+#include <drm/drm_of.h>
+#include <drm/drm_panel.h>
+#include <drm/drm_plane.h>
+#include <drm/drm_plane_helper.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_vblank.h>
+
+#include <dt-bindings/display/ingenic,drm.h>
+
+#define JZ_REG_LCD_CFG		0x00
+#define JZ_REG_LCD_VSYNC	0x04
+#define JZ_REG_LCD_HSYNC	0x08
+#define JZ_REG_LCD_VAT		0x0C
+#define JZ_REG_LCD_DAH		0x10
+#define JZ_REG_LCD_DAV		0x14
+#define JZ_REG_LCD_PS		0x18
+#define JZ_REG_LCD_CLS		0x1C
+#define JZ_REG_LCD_SPL		0x20
+#define JZ_REG_LCD_REV		0x24
+#define JZ_REG_LCD_CTRL		0x30
+#define JZ_REG_LCD_STATE	0x34
+#define JZ_REG_LCD_IID		0x38
+#define JZ_REG_LCD_DA0		0x40
+#define JZ_REG_LCD_SA0		0x44
+#define JZ_REG_LCD_FID0		0x48
+#define JZ_REG_LCD_CMD0		0x4C
+#define JZ_REG_LCD_DA1		0x50
+#define JZ_REG_LCD_SA1		0x54
+#define JZ_REG_LCD_FID1		0x58
+#define JZ_REG_LCD_CMD1		0x5C
+
+#define JZ_LCD_CFG_SLCD			BIT(31)
+#define JZ_LCD_CFG_PS_DISABLE		BIT(23)
+#define JZ_LCD_CFG_CLS_DISABLE		BIT(22)
+#define JZ_LCD_CFG_SPL_DISABLE		BIT(21)
+#define JZ_LCD_CFG_REV_DISABLE		BIT(20)
+#define JZ_LCD_CFG_HSYNCM		BIT(19)
+#define JZ_LCD_CFG_PCLKM		BIT(18)
+#define JZ_LCD_CFG_INV			BIT(17)
+#define JZ_LCD_CFG_SYNC_DIR		BIT(16)
+#define JZ_LCD_CFG_PS_POLARITY		BIT(15)
+#define JZ_LCD_CFG_CLS_POLARITY		BIT(14)
+#define JZ_LCD_CFG_SPL_POLARITY		BIT(13)
+#define JZ_LCD_CFG_REV_POLARITY		BIT(12)
+#define JZ_LCD_CFG_HSYNC_ACTIVE_LOW	BIT(11)
+#define JZ_LCD_CFG_PCLK_FALLING_EDGE	BIT(10)
+#define JZ_LCD_CFG_DE_ACTIVE_LOW	BIT(9)
+#define JZ_LCD_CFG_VSYNC_ACTIVE_LOW	BIT(8)
+#define JZ_LCD_CFG_18_BIT		BIT(7)
+#define JZ_LCD_CFG_PDW			(BIT(5) | BIT(4))
+#define JZ_LCD_CFG_MODE_MASK		0xf
+
+#define JZ_LCD_VSYNC_VPS_OFFSET		16
+#define JZ_LCD_VSYNC_VPE_OFFSET		0
+
+#define JZ_LCD_HSYNC_HPS_OFFSET		16
+#define JZ_LCD_HSYNC_HPE_OFFSET		0
+
+#define JZ_LCD_VAT_HT_OFFSET		16
+#define JZ_LCD_VAT_VT_OFFSET		0
+
+#define JZ_LCD_DAH_HDS_OFFSET		16
+#define JZ_LCD_DAH_HDE_OFFSET		0
+
+#define JZ_LCD_DAV_VDS_OFFSET		16
+#define JZ_LCD_DAV_VDE_OFFSET		0
+
+#define JZ_LCD_CTRL_BURST_4		(0x0 << 28)
+#define JZ_LCD_CTRL_BURST_8		(0x1 << 28)
+#define JZ_LCD_CTRL_BURST_16		(0x2 << 28)
+#define JZ_LCD_CTRL_RGB555		BIT(27)
+#define JZ_LCD_CTRL_OFUP		BIT(26)
+#define JZ_LCD_CTRL_FRC_GRAYSCALE_16	(0x0 << 24)
+#define JZ_LCD_CTRL_FRC_GRAYSCALE_4	(0x1 << 24)
+#define JZ_LCD_CTRL_FRC_GRAYSCALE_2	(0x2 << 24)
+#define JZ_LCD_CTRL_PDD_MASK		(0xff << 16)
+#define JZ_LCD_CTRL_EOF_IRQ		BIT(13)
+#define JZ_LCD_CTRL_SOF_IRQ		BIT(12)
+#define JZ_LCD_CTRL_OFU_IRQ		BIT(11)
+#define JZ_LCD_CTRL_IFU0_IRQ		BIT(10)
+#define JZ_LCD_CTRL_IFU1_IRQ		BIT(9)
+#define JZ_LCD_CTRL_DD_IRQ		BIT(8)
+#define JZ_LCD_CTRL_QDD_IRQ		BIT(7)
+#define JZ_LCD_CTRL_REVERSE_ENDIAN	BIT(6)
+#define JZ_LCD_CTRL_LSB_FISRT		BIT(5)
+#define JZ_LCD_CTRL_DISABLE		BIT(4)
+#define JZ_LCD_CTRL_ENABLE		BIT(3)
+#define JZ_LCD_CTRL_BPP_1		0x0
+#define JZ_LCD_CTRL_BPP_2		0x1
+#define JZ_LCD_CTRL_BPP_4		0x2
+#define JZ_LCD_CTRL_BPP_8		0x3
+#define JZ_LCD_CTRL_BPP_15_16		0x4
+#define JZ_LCD_CTRL_BPP_18_24		0x5
+#define JZ_LCD_CTRL_BPP_MASK		(JZ_LCD_CTRL_RGB555 | (0x7 << 0))
+
+#define JZ_LCD_CMD_SOF_IRQ		BIT(31)
+#define JZ_LCD_CMD_EOF_IRQ		BIT(30)
+#define JZ_LCD_CMD_ENABLE_PAL		BIT(28)
+
+#define JZ_LCD_SYNC_MASK		0x3ff
+
+#define JZ_LCD_STATE_EOF_IRQ		BIT(5)
+#define JZ_LCD_STATE_SOF_IRQ		BIT(4)
+#define JZ_LCD_STATE_DISABLED		BIT(0)
+
+struct ingenic_dma_hwdesc {
+	u32 next;
+	u32 addr;
+	u32 id;
+	u32 cmd;
+} __packed;
+
+struct jz_soc_info {
+	bool needs_dev_clk;
+};
+
+struct ingenic_drm {
+	struct device *dev;
+	void __iomem *base;
+	struct regmap *map;
+	struct clk *lcd_clk, *pix_clk;
+
+	u32 lcd_mode;
+
+	struct ingenic_dma_hwdesc *framedesc;
+	dma_addr_t framedesc_phys;
+
+	struct drm_device *drm;
+	struct drm_plane primary;
+	struct drm_crtc crtc;
+	struct drm_encoder encoder;
+};
+
+static const u32 ingenic_drm_primary_formats[] = {
+	DRM_FORMAT_XRGB1555,
+	DRM_FORMAT_RGB565,
+	DRM_FORMAT_XRGB8888,
+};
+
+static bool ingenic_drm_writeable_reg(struct device *dev, unsigned int reg)
+{
+	switch (reg) {
+	case JZ_REG_LCD_IID:
+	case JZ_REG_LCD_SA0:
+	case JZ_REG_LCD_FID0:
+	case JZ_REG_LCD_CMD0:
+	case JZ_REG_LCD_SA1:
+	case JZ_REG_LCD_FID1:
+	case JZ_REG_LCD_CMD1:
+		return false;
+	default:
+		return true;
+	}
+}
+
+static const struct regmap_config ingenic_drm_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+
+	.max_register = JZ_REG_LCD_CMD1,
+	.writeable_reg = ingenic_drm_writeable_reg,
+};
+
+static inline struct ingenic_drm *drm_crtc_get_priv(struct drm_crtc *crtc)
+{
+	return container_of(crtc, struct ingenic_drm, crtc);
+}
+
+static inline struct ingenic_drm *
+drm_encoder_get_priv(struct drm_encoder *encoder)
+{
+	return container_of(encoder, struct ingenic_drm, encoder);
+}
+
+static inline struct ingenic_drm *drm_plane_get_priv(struct drm_plane *plane)
+{
+	return container_of(plane, struct ingenic_drm, primary);
+}
+
+static void ingenic_drm_crtc_atomic_enable(struct drm_crtc *crtc,
+					  struct drm_crtc_state *state)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+
+	regmap_write(priv->map, JZ_REG_LCD_STATE, 0);
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
+			   JZ_LCD_CTRL_ENABLE | JZ_LCD_CTRL_DISABLE,
+			   JZ_LCD_CTRL_ENABLE);
+
+	drm_crtc_vblank_on(crtc);
+}
+
+static void ingenic_drm_crtc_atomic_disable(struct drm_crtc *crtc,
+					   struct drm_crtc_state *state)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+	unsigned int var;
+
+	drm_crtc_vblank_off(crtc);
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
+			   JZ_LCD_CTRL_DISABLE, JZ_LCD_CTRL_DISABLE);
+
+	regmap_read_poll_timeout(priv->map, JZ_REG_LCD_STATE, var,
+				 var & JZ_LCD_STATE_DISABLED,
+				 1000, 0);
+}
+
+static inline bool ingenic_drm_lcd_is_special_mode(u32 mode)
+{
+	switch (mode) {
+	case JZ_DRM_LCD_SPECIAL_TFT_1:
+	case JZ_DRM_LCD_SPECIAL_TFT_2:
+	case JZ_DRM_LCD_SPECIAL_TFT_3:
+		return true;
+	default:
+		return false;
+	}
+}
+
+static void ingenic_drm_crtc_update_timings(struct ingenic_drm *priv,
+					    struct drm_display_mode *mode)
+{
+	unsigned int vpe, vds, vde, vt, hpe, hds, hde, ht;
+
+	vpe = mode->vsync_end - mode->vsync_start;
+	vds = mode->vtotal - mode->vsync_start;
+	vde = vds + mode->vdisplay;
+	vt = vde + mode->vsync_start - mode->vdisplay;
+
+	hpe = mode->hsync_end - mode->hsync_start;
+	hds = mode->htotal - mode->hsync_start;
+	hde = hds + mode->hdisplay;
+	ht = hde + mode->hsync_start - mode->hdisplay;
+
+	regmap_write(priv->map, JZ_REG_LCD_VSYNC,
+		     0 << JZ_LCD_VSYNC_VPS_OFFSET |
+		     vpe << JZ_LCD_VSYNC_VPE_OFFSET);
+
+	regmap_write(priv->map, JZ_REG_LCD_HSYNC,
+		     0 << JZ_LCD_HSYNC_HPS_OFFSET |
+		     hpe << JZ_LCD_HSYNC_HPE_OFFSET);
+
+	regmap_write(priv->map, JZ_REG_LCD_VAT,
+		     ht << JZ_LCD_VAT_HT_OFFSET |
+		     vt << JZ_LCD_VAT_VT_OFFSET);
+
+	regmap_write(priv->map, JZ_REG_LCD_DAH,
+		     hds << JZ_LCD_DAH_HDS_OFFSET |
+		     hde << JZ_LCD_DAH_HDE_OFFSET);
+	regmap_write(priv->map, JZ_REG_LCD_DAV,
+		     vds << JZ_LCD_DAV_VDS_OFFSET |
+		     vde << JZ_LCD_DAV_VDE_OFFSET);
+
+	if (ingenic_drm_lcd_is_special_mode(priv->lcd_mode)) {
+		regmap_write(priv->map, JZ_REG_LCD_PS, hde << 16 | (hde + 1));
+		regmap_write(priv->map, JZ_REG_LCD_CLS, hde << 16 | (hde + 1));
+		regmap_write(priv->map, JZ_REG_LCD_SPL, hpe << 16 | (hpe + 1));
+		regmap_write(priv->map, JZ_REG_LCD_REV, mode->htotal << 16);
+	}
+}
+
+static void ingenic_drm_crtc_update_ctrl(struct ingenic_drm *priv,
+					 unsigned int bpp)
+{
+	unsigned int ctrl = JZ_LCD_CTRL_OFUP | JZ_LCD_CTRL_BURST_16;
+
+	switch (bpp) {
+	case 1:
+		ctrl |= JZ_LCD_CTRL_BPP_1;
+		break;
+	case 2:
+		ctrl |= JZ_LCD_CTRL_BPP_2;
+		break;
+	case 4:
+		ctrl |= JZ_LCD_CTRL_BPP_4;
+		break;
+	case 8:
+		ctrl |= JZ_LCD_CTRL_BPP_8;
+	break;
+	case 15:
+		ctrl |= JZ_LCD_CTRL_RGB555; /* Falltrough */
+	case 16:
+		ctrl |= JZ_LCD_CTRL_BPP_15_16;
+		break;
+	case 18:
+	case 24:
+	case 32:
+		ctrl |= JZ_LCD_CTRL_BPP_18_24;
+		break;
+	default:
+		break;
+	}
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
+			   JZ_LCD_CTRL_OFUP | JZ_LCD_CTRL_BURST_16 |
+			   JZ_LCD_CTRL_BPP_MASK, ctrl);
+}
+
+static int ingenic_drm_crtc_atomic_check(struct drm_crtc *crtc,
+					 struct drm_crtc_state *state)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+	long rate;
+
+	if (!drm_atomic_crtc_needs_modeset(state))
+		return 0;
+
+	rate = clk_round_rate(priv->pix_clk,
+			      state->adjusted_mode.clock * 1000);
+	if (rate < 0)
+		return rate;
+
+	return 0;
+}
+
+static void ingenic_drm_crtc_atomic_flush(struct drm_crtc *crtc,
+					  struct drm_crtc_state *oldstate)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+	struct drm_crtc_state *state = crtc->state;
+	struct drm_pending_vblank_event *event = state->event;
+	struct drm_framebuffer *drm_fb = crtc->primary->state->fb;
+	const struct drm_format_info *finfo;
+
+	if (drm_atomic_crtc_needs_modeset(state)) {
+		finfo = drm_format_info(drm_fb->format->format);
+
+		ingenic_drm_crtc_update_timings(priv, &state->mode);
+		ingenic_drm_crtc_update_ctrl(priv, finfo->depth);
+
+		clk_set_rate(priv->pix_clk, state->adjusted_mode.clock * 1000);
+
+		regmap_write(priv->map, JZ_REG_LCD_DA0, priv->framedesc->next);
+	}
+
+	if (event) {
+		state->event = NULL;
+
+		spin_lock_irq(&crtc->dev->event_lock);
+		if (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 void ingenic_drm_plane_atomic_update(struct drm_plane *plane,
+					    struct drm_plane_state *oldstate)
+{
+	struct ingenic_drm *priv = drm_plane_get_priv(plane);
+	struct drm_plane_state *state = plane->state;
+	const struct drm_format_info *finfo;
+	unsigned int width, height;
+
+	finfo = drm_format_info(state->fb->format->format);
+	width = state->crtc->state->adjusted_mode.hdisplay;
+	height = state->crtc->state->adjusted_mode.vdisplay;
+
+	priv->framedesc->addr = drm_fb_cma_get_gem_addr(state->fb, state, 0);
+
+	priv->framedesc->cmd = width * height * ((finfo->depth + 7) / 8) / 4;
+	priv->framedesc->cmd |= JZ_LCD_CMD_EOF_IRQ;
+}
+
+static void ingenic_drm_encoder_atomic_mode_set(struct drm_encoder *encoder,
+						struct drm_crtc_state *crtc_state,
+						struct drm_connector_state *conn_state)
+{
+	struct ingenic_drm *priv = drm_encoder_get_priv(encoder);
+	struct drm_display_mode *mode = &crtc_state->adjusted_mode;
+	u32 bus_flags = conn_state->connector->display_info.bus_flags;
+	unsigned int cfg = priv->lcd_mode;
+
+	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+		cfg |= JZ_LCD_CFG_HSYNC_ACTIVE_LOW;
+	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+		cfg |= JZ_LCD_CFG_VSYNC_ACTIVE_LOW;
+	if (bus_flags & DRM_BUS_FLAG_DE_LOW)
+		cfg |= JZ_LCD_CFG_DE_ACTIVE_LOW;
+	if (bus_flags & DRM_BUS_FLAG_PIXDATA_NEGEDGE)
+		cfg |= JZ_LCD_CFG_PCLK_FALLING_EDGE;
+
+	if (ingenic_drm_lcd_is_special_mode(priv->lcd_mode)) {
+		/* TODO: Is that valid for all special modes? */
+		cfg |= JZ_LCD_CFG_REV_POLARITY;
+	} else {
+		cfg |= JZ_LCD_CFG_PS_DISABLE
+		    | JZ_LCD_CFG_CLS_DISABLE
+		    | JZ_LCD_CFG_SPL_DISABLE
+		    | JZ_LCD_CFG_REV_DISABLE;
+	}
+
+	regmap_write(priv->map, JZ_REG_LCD_CFG, cfg);
+}
+
+static irqreturn_t ingenic_drm_irq_handler(int irq, void *arg)
+{
+	struct drm_device *drm = arg;
+	struct ingenic_drm *priv = drm->dev_private;
+	unsigned int state;
+
+	regmap_read(priv->map, JZ_REG_LCD_STATE, &state);
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_STATE,
+			   JZ_LCD_STATE_EOF_IRQ, 0);
+
+	if (state & JZ_LCD_STATE_EOF_IRQ)
+		drm_crtc_handle_vblank(&priv->crtc);
+
+	return IRQ_HANDLED;
+}
+
+static int ingenic_drm_enable_vblank(struct drm_crtc *crtc)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
+			   JZ_LCD_CTRL_EOF_IRQ, JZ_LCD_CTRL_EOF_IRQ);
+
+	return 0;
+}
+
+static void ingenic_drm_disable_vblank(struct drm_crtc *crtc)
+{
+	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL, JZ_LCD_CTRL_EOF_IRQ, 0);
+}
+
+DEFINE_DRM_GEM_CMA_FOPS(ingenic_drm_fops);
+
+static struct drm_driver ingenic_drm_driver_data = {
+	.driver_features	= DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME
+				| DRIVER_ATOMIC,
+	.name			= "ingenic-drm",
+	.desc			= "DRM module for Ingenic SoCs",
+	.date			= "20190228",
+	.major			= 1,
+	.minor			= 0,
+	.patchlevel		= 0,
+
+	.fops			= &ingenic_drm_fops,
+
+	.dumb_create		= drm_gem_cma_dumb_create,
+	.gem_free_object_unlocked = drm_gem_cma_free_object,
+	.gem_vm_ops		= &drm_gem_cma_vm_ops,
+
+	.prime_handle_to_fd	= drm_gem_prime_handle_to_fd,
+	.prime_fd_to_handle	= drm_gem_prime_fd_to_handle,
+	.gem_prime_get_sg_table	= drm_gem_cma_prime_get_sg_table,
+	.gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table,
+	.gem_prime_vmap		= drm_gem_cma_prime_vmap,
+	.gem_prime_vunmap	= drm_gem_cma_prime_vunmap,
+	.gem_prime_mmap		= drm_gem_cma_prime_mmap,
+
+	.irq_handler		= ingenic_drm_irq_handler,
+};
+
+static const struct drm_plane_funcs ingenic_drm_primary_plane_funcs = {
+	.update_plane		= drm_atomic_helper_update_plane,
+	.disable_plane		= drm_atomic_helper_disable_plane,
+	.reset			= drm_atomic_helper_plane_reset,
+
+	.atomic_duplicate_state	= drm_atomic_helper_plane_duplicate_state,
+	.atomic_destroy_state	= drm_atomic_helper_plane_destroy_state,
+};
+
+static const struct drm_crtc_funcs ingenic_drm_crtc_funcs = {
+	.reset			= drm_atomic_helper_crtc_reset,
+	.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,
+
+	.enable_vblank		= ingenic_drm_enable_vblank,
+	.disable_vblank		= ingenic_drm_disable_vblank,
+
+	.gamma_set		= drm_atomic_helper_legacy_gamma_set,
+};
+
+static const struct drm_plane_helper_funcs ingenic_drm_plane_helper_funcs = {
+	.atomic_update		= ingenic_drm_plane_atomic_update,
+	.prepare_fb		= drm_gem_fb_prepare_fb,
+};
+
+static const struct drm_crtc_helper_funcs ingenic_drm_crtc_helper_funcs = {
+	.atomic_enable		= ingenic_drm_crtc_atomic_enable,
+	.atomic_disable		= ingenic_drm_crtc_atomic_disable,
+	.atomic_flush		= ingenic_drm_crtc_atomic_flush,
+	.atomic_check		= ingenic_drm_crtc_atomic_check,
+};
+
+static const struct drm_encoder_helper_funcs ingenic_drm_encoder_helper_funcs = {
+	.atomic_mode_set	= ingenic_drm_encoder_atomic_mode_set,
+};
+
+static const struct drm_mode_config_funcs ingenic_drm_mode_config_funcs = {
+	.fb_create		= drm_gem_fb_create,
+	.output_poll_changed	= drm_fb_helper_output_poll_changed,
+	.atomic_check		= drm_atomic_helper_check,
+	.atomic_commit		= drm_atomic_helper_commit,
+};
+
+static const struct drm_encoder_funcs ingenic_drm_encoder_funcs = {
+	.destroy		= drm_encoder_cleanup,
+};
+
+static int ingenic_drm_probe(struct platform_device *pdev)
+{
+	const struct jz_soc_info *soc_info;
+	struct device *dev = &pdev->dev;
+	struct ingenic_drm *priv;
+	struct clk *parent_clk;
+	struct drm_bridge *bridge;
+	struct drm_panel *panel;
+	struct drm_device *drm;
+	struct resource *mem;
+	void __iomem *base;
+	long parent_rate;
+	int ret, irq;
+
+	soc_info = device_get_match_data(dev);
+	if (!soc_info)
+		return -EINVAL;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->dev = dev;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	priv->base = base = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(dev, "Failed to get platform irq\n");
+		return -ENOENT;
+	}
+
+	priv->map = devm_regmap_init_mmio(dev, base,
+					  &ingenic_drm_regmap_config);
+	if (IS_ERR(priv->map)) {
+		dev_err(dev, "Failed to create regmap\n");
+		return PTR_ERR(priv->map);
+	}
+
+	if (soc_info->needs_dev_clk) {
+		priv->lcd_clk = devm_clk_get(dev, "lcd");
+		if (IS_ERR(priv->lcd_clk)) {
+			dev_err(dev, "Failed to get lcd clock\n");
+			return PTR_ERR(priv->lcd_clk);
+		}
+	}
+
+	priv->pix_clk = devm_clk_get(dev, "lcd_pclk");
+	if (IS_ERR(priv->pix_clk)) {
+		dev_err(dev, "Failed to get pixel clock\n");
+		return PTR_ERR(priv->pix_clk);
+	}
+
+	ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &panel, &bridge);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "Failed to get panel handle\n");
+		return ret;
+	}
+
+	if (panel) {
+		bridge = devm_drm_panel_bridge_add(dev, panel,
+						   DRM_MODE_CONNECTOR_Unknown);
+	}
+
+	device_property_read_u32(dev, "ingenic,lcd-mode", &priv->lcd_mode);
+
+	priv->framedesc = dma_alloc_coherent(dev, sizeof(*priv->framedesc),
+					     &priv->framedesc_phys, GFP_KERNEL);
+	if (!priv->framedesc)
+		return -ENOMEM;
+
+	priv->framedesc->next = priv->framedesc_phys;
+	priv->framedesc->id = 0xdeafbead;
+
+	drm = drm_dev_alloc(&ingenic_drm_driver_data, dev);
+	if (IS_ERR(drm)) {
+		ret = PTR_ERR(drm);
+		goto err_free_dma;
+	}
+
+	priv->drm = drm;
+
+	drm_mode_config_init(drm);
+	drm->mode_config.min_width = 0;
+	drm->mode_config.min_height = 0;
+	drm->mode_config.max_width = 800;
+	drm->mode_config.max_height = 600;
+	drm->mode_config.funcs = &ingenic_drm_mode_config_funcs;
+
+	drm_plane_helper_add(&priv->primary, &ingenic_drm_plane_helper_funcs);
+
+	ret = drm_universal_plane_init(drm, &priv->primary,
+				       0, &ingenic_drm_primary_plane_funcs,
+				       ingenic_drm_primary_formats,
+				       ARRAY_SIZE(ingenic_drm_primary_formats),
+				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
+	if (ret) {
+		dev_err(dev, "Failed to register primary plane: %i\n", ret);
+		goto err_unref_drm;
+	}
+
+	drm_crtc_helper_add(&priv->crtc, &ingenic_drm_crtc_helper_funcs);
+
+	ret = drm_crtc_init_with_planes(drm, &priv->crtc, &priv->primary,
+					NULL, &ingenic_drm_crtc_funcs, NULL);
+	if (ret) {
+		dev_err(dev, "Failed to init CRTC: %i\n", ret);
+		goto err_cleanup_plane;
+	}
+
+	priv->encoder.possible_crtcs = 1;
+
+	drm_encoder_helper_add(&priv->encoder,
+			       &ingenic_drm_encoder_helper_funcs);
+
+	ret = drm_encoder_init(drm, &priv->encoder, &ingenic_drm_encoder_funcs,
+			       DRM_MODE_ENCODER_DPI, NULL);
+	if (ret) {
+		dev_err(dev, "Failed to init encoder: %i\n", ret);
+		goto err_cleanup_crtc;
+	}
+
+	ret = drm_bridge_attach(&priv->encoder, bridge, NULL);
+	if (ret) {
+		dev_err(dev, "Unable to attach bridge\n");
+		goto err_cleanup_encoder;
+	}
+
+	platform_set_drvdata(pdev, drm);
+	priv->drm = drm;
+	drm->dev_private = priv;
+
+	ret = drm_irq_install(drm, irq);
+	if (ret) {
+		dev_err(dev, "Unable to install IRQ handler\n");
+		goto err_cleanup_encoder;
+	}
+
+	ret = drm_vblank_init(drm, 1);
+	if (ret) {
+		dev_err(dev, "Failed calling drm_vblank_init()\n");
+		goto err_uninstall_irq;
+	}
+
+	drm_mode_config_reset(drm);
+
+	ret = clk_prepare_enable(priv->pix_clk);
+	if (ret) {
+		dev_err(dev, "Unable to start pixel clock\n");
+		goto err_uninstall_irq;
+	}
+
+	if (priv->lcd_clk) {
+		parent_clk = clk_get_parent(priv->lcd_clk);
+		parent_rate = clk_get_rate(parent_clk);
+
+		/* LCD Device clock must be 3x the pixel clock for STN panels,
+		 * or 1.5x the pixel clock for TFT panels. To avoid having to
+		 * check for the LCD device clock everytime we do a mode change,
+		 * we set the LCD device clock to the highest rate possible.
+		 */
+		ret = clk_set_rate(priv->lcd_clk, parent_rate);
+		if (ret) {
+			dev_err(dev, "Unable to set LCD clock rate\n");
+			goto err_pixclk_disable;
+		}
+
+		ret = clk_prepare_enable(priv->lcd_clk);
+		if (ret) {
+			dev_err(dev, "Unable to start lcd clock\n");
+			goto err_pixclk_disable;
+		}
+	}
+
+	ret = drm_fbdev_generic_setup(drm, 16);
+	if (ret) {
+		dev_err(dev, "Failed to init fbdev\n");
+		goto err_devclk_disable;
+	}
+
+	ret = drm_dev_register(drm, 0);
+	if (ret) {
+		dev_err(dev, "Failed to register DRM driver\n");
+		goto err_cleanup_fbdev;
+	}
+
+	return 0;
+
+err_cleanup_fbdev:
+	drm_mode_config_cleanup(drm);
+err_devclk_disable:
+	if (priv->lcd_clk)
+		clk_disable_unprepare(priv->lcd_clk);
+err_pixclk_disable:
+	clk_disable_unprepare(priv->pix_clk);
+err_uninstall_irq:
+	drm_irq_uninstall(drm);
+err_cleanup_encoder:
+	drm_encoder_cleanup(&priv->encoder);
+err_cleanup_crtc:
+	drm_crtc_cleanup(&priv->crtc);
+err_cleanup_plane:
+	drm_plane_cleanup(&priv->primary);
+err_unref_drm:
+	drm_dev_put(drm);
+err_free_dma:
+	dma_free_coherent(dev, sizeof(*priv->framedesc),
+			  priv->framedesc, priv->framedesc_phys);
+	return ret;
+}
+
+static int ingenic_drm_remove(struct platform_device *pdev)
+{
+	struct drm_device *drm = platform_get_drvdata(pdev);
+	struct ingenic_drm *priv = drm->dev_private;
+
+	drm_dev_unregister(drm);
+	drm_mode_config_cleanup(drm);
+
+	if (priv->lcd_clk)
+		clk_disable_unprepare(priv->lcd_clk);
+	clk_disable_unprepare(priv->pix_clk);
+
+	drm_irq_uninstall(drm);
+
+	drm_encoder_cleanup(&priv->encoder);
+	drm_crtc_cleanup(&priv->crtc);
+	drm_plane_cleanup(&priv->primary);
+
+	drm_dev_put(drm);
+
+	dma_free_coherent(&pdev->dev, sizeof(*priv->framedesc),
+			  priv->framedesc, priv->framedesc_phys);
+
+	return 0;
+}
+
+static const struct jz_soc_info jz4740_soc_info = {
+	.needs_dev_clk = true,
+};
+
+static const struct jz_soc_info jz4725b_soc_info = {
+	.needs_dev_clk = false,
+};
+
+static const struct of_device_id ingenic_drm_of_match[] = {
+	{ .compatible = "ingenic,jz4740-drm", .data = &jz4740_soc_info },
+	{ .compatible = "ingenic,jz4725b-drm", .data = &jz4725b_soc_info },
+	{ /* sentinel */ },
+};
+
+static struct platform_driver ingenic_drm_driver = {
+	.driver = {
+		.name = "ingenic-drm",
+		.of_match_table = of_match_ptr(ingenic_drm_of_match),
+	},
+	.probe = ingenic_drm_probe,
+	.remove = ingenic_drm_remove,
+};
+module_platform_driver(ingenic_drm_driver);
+
+MODULE_AUTHOR("Paul Cercueil <paul@crapouillou.net>");
+MODULE_DESCRIPTION("DRM driver for the Ingenic SoCs\n");
+MODULE_LICENSE("GPL v2");
-- 
2.11.0

Re: [PATCH v2 1/3] dt-bindings: Add doc for the ingenic-drm driver

[Paul Cercueil]

Le ven. 15 mars 2019 à 18:06, Paul Cercueil <paul@crapouillou.net> a 
écrit :
> Add documentation for the devicetree bindings of the DRM driver for 
> the
> JZ47xx family of SoCs from Ingenic.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Tested-by: Artur Rojek <contact@artur-rojek.eu>
> ---
> 
> Notes:
>     v2: Remove ingenic,panel property.
> 
>  .../devicetree/bindings/display/ingenic,drm.txt    | 29 
> ++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
>  create mode 100644 
> Documentation/devicetree/bindings/display/ingenic,drm.txt
> 
> diff --git 
> a/Documentation/devicetree/bindings/display/ingenic,drm.txt 
> b/Documentation/devicetree/bindings/display/ingenic,drm.txt
> new file mode 100644
> index 000000000000..f57a4ae0f7ac
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/ingenic,drm.txt
> @@ -0,0 +1,29 @@
> +Ingenic JZ47xx DRM driver
> +
> +Required properties:
> +- compatible: one of:
> +  * ingenic,jz4740-drm
> +  * ingenic,jz4725b-drm

Ooops, I forgot to fix what Rob pointed out. Will do in V3.

-Paul

> +- reg: LCD registers location and length
> +- clocks: LCD pixclock and device clock specifiers.
> +	   The device clock is only required on the JZ4740.
> +- clock-names: "lcd_pclk" and "lcd"
> +- interrupts: Specifies the interrupt line the LCD controller is 
> connected to.
> +
> +Optional properties:
> +- ingenic,lcd-mode: LCD mode to use with the display panel.
> +		    See <dt-bindings/display/ingenic,drm.h> for all the
> +		    possible values.
> +
> +Example:
> +
> +lcd: lcd-controller@13050000 {
> +	compatible = "ingenic,jz4725b-drm";
> +	reg = <0x13050000 0x1000>;
> +
> +	interrupt-parent = <&intc>;
> +	interrupts = <31>;
> +
> +	clocks = <&cgu JZ4725B_CLK_LCD>;
> +	clock-names = "lcd";
> +};
> --
> 2.11.0
> 

Re: [PATCH v2 1/3] dt-bindings: Add doc for the ingenic-drm driver

[Sam Ravnborg]

Hi Paul.

On Fri, Mar 15, 2019 at 06:06:59PM +0100, Paul Cercueil wrote:
> Add documentation for the devicetree bindings of the DRM driver for the
> JZ47xx family of SoCs from Ingenic.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Tested-by: Artur Rojek <contact@artur-rojek.eu>
> ---
> 
> Notes:
>     v2: Remove ingenic,panel property.
> 
>  .../devicetree/bindings/display/ingenic,drm.txt    | 29 ++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/display/ingenic,drm.txt
> 
> diff --git a/Documentation/devicetree/bindings/display/ingenic,drm.txt b/Documentation/devicetree/bindings/display/ingenic,drm.txt
> new file mode 100644
> index 000000000000..f57a4ae0f7ac
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/display/ingenic,drm.txt
> @@ -0,0 +1,29 @@
> +Ingenic JZ47xx DRM driver
> +
> +Required properties:
> +- compatible: one of:
> +  * ingenic,jz4740-drm
> +  * ingenic,jz4725b-drm
> +- reg: LCD registers location and length
> +- clocks: LCD pixclock and device clock specifiers.
> +	   The device clock is only required on the JZ4740.
> +- clock-names: "lcd_pclk" and "lcd"
> +- interrupts: Specifies the interrupt line the LCD controller is connected to.
> +
> +Optional properties:
> +- ingenic,lcd-mode: LCD mode to use with the display panel.
> +		    See <dt-bindings/display/ingenic,drm.h> for all the
> +		    possible values.

The value of the ingenic,lcd-mode depends on the panel used.
So this looks like a panel property and not a display property.

The panel should be specified using an OF graph binding
in a port sub-node.
The remote-endpoint will specifify the panel properties
and if the panel requires something special from the display driver,
the panle should specify this.
So one can change panel without touching the display node
in the DT.


> +
> +Example:
> +
> +lcd: lcd-controller@13050000 {
> +	compatible = "ingenic,jz4725b-drm";
> +	reg = <0x13050000 0x1000>;
> +
> +	interrupt-parent = <&intc>;
> +	interrupts = <31>;
> +
> +	clocks = <&cgu JZ4725B_CLK_LCD>;
> +	clock-names = "lcd";
> +};

As hinted above the panel is not specified above and to follow the
modern way to do so would be to use a OF graph binding.

	Sam
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Re: [PATCH v2 1/3] dt-bindings: Add doc for the ingenic-drm driver

[Paul Cercueil]

Hi Sam,

Le sam. 16 mars 2019 à 21:59, Sam Ravnborg <sam@ravnborg.org> a écrit 
:
> Hi Paul.
> 
> On Fri, Mar 15, 2019 at 06:06:59PM +0100, Paul Cercueil wrote:
>>  Add documentation for the devicetree bindings of the DRM driver for 
>> the
>>  JZ47xx family of SoCs from Ingenic.
>> 
>>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>>  Tested-by: Artur Rojek <contact@artur-rojek.eu>
>>  ---
>> 
>>  Notes:
>>      v2: Remove ingenic,panel property.
>> 
>>   .../devicetree/bindings/display/ingenic,drm.txt    | 29 
>> ++++++++++++++++++++++
>>   1 file changed, 29 insertions(+)
>>   create mode 100644 
>> Documentation/devicetree/bindings/display/ingenic,drm.txt
>> 
>>  diff --git 
>> a/Documentation/devicetree/bindings/display/ingenic,drm.txt 
>> b/Documentation/devicetree/bindings/display/ingenic,drm.txt
>>  new file mode 100644
>>  index 000000000000..f57a4ae0f7ac
>>  --- /dev/null
>>  +++ b/Documentation/devicetree/bindings/display/ingenic,drm.txt
>>  @@ -0,0 +1,29 @@
>>  +Ingenic JZ47xx DRM driver
>>  +
>>  +Required properties:
>>  +- compatible: one of:
>>  +  * ingenic,jz4740-drm
>>  +  * ingenic,jz4725b-drm
>>  +- reg: LCD registers location and length
>>  +- clocks: LCD pixclock and device clock specifiers.
>>  +	   The device clock is only required on the JZ4740.
>>  +- clock-names: "lcd_pclk" and "lcd"
>>  +- interrupts: Specifies the interrupt line the LCD controller is 
>> connected to.
>>  +
>>  +Optional properties:
>>  +- ingenic,lcd-mode: LCD mode to use with the display panel.
>>  +		    See <dt-bindings/display/ingenic,drm.h> for all the
>>  +		    possible values.
> 
> The value of the ingenic,lcd-mode depends on the panel used.
> So this looks like a panel property and not a display property.
> 
> The panel should be specified using an OF graph binding
> in a port sub-node.
> The remote-endpoint will specifify the panel properties
> and if the panel requires something special from the display driver,
> the panle should specify this.
> So one can change panel without touching the display node
> in the DT.

Then the 'ingenic,lcd-mode' property would be in the panel node,
even though it's not used by the panel driver but by the DRM driver?
That sounds strange to me.

>>  +
>>  +Example:
>>  +
>>  +lcd: lcd-controller@13050000 {
>>  +	compatible = "ingenic,jz4725b-drm";
>>  +	reg = <0x13050000 0x1000>;
>>  +
>>  +	interrupt-parent = <&intc>;
>>  +	interrupts = <31>;
>>  +
>>  +	clocks = <&cgu JZ4725B_CLK_LCD>;
>>  +	clock-names = "lcd";
>>  +};
> 
> As hinted above the panel is not specified above and to follow the
> modern way to do so would be to use a OF graph binding.

It's done this way in the DRM driver now, but I didn't update the
example. I will update it in the next version.

-Paul

Re: [PATCH v2 3/3] DRM: Add KMS driver for the Ingenic JZ47xx SoCs

[Sam Ravnborg]

Hi Paul.

Thanks for the v2 submission.

Did you analyze the possibility to utilize drm_simple_display_pipe_init()
and the related infrastructure?
If this fits it should simplify the driver.
If it does not fit please let us know why.
As this is a one crtc / one connector / one panel the drm_simple_*
infrastructure is supposed to be a good fit.

Some smaller comments in the following.
Most are suggestion, do not follow these blindly.

	Sam

> Add a KMS driver for the Ingenic JZ47xx family of SoCs.
> This driver is meant to replace the aging jz4740-fb driver.
> 
> Signed-off-by: Paul Cercueil <paul@crapouillou.net>
> Tested-by: Artur Rojek <contact@artur-rojek.eu>

> +struct ingenic_drm {
> +	struct device *dev;
> +	void __iomem *base;
> +	struct regmap *map;
> +	struct clk *lcd_clk, *pix_clk;
> +
> +	u32 lcd_mode;
> +
> +	struct ingenic_dma_hwdesc *framedesc;

Consider the name "dma_hwdesc" for this.
The struct is named so, which give a good indication
this is a more descriptive name.

That said, the current solution looks much cleaner than the
previous one.

> +	dma_addr_t framedesc_phys;
Likewise.


> +
> +	struct drm_device *drm;
If drm is embedded you can use devm_drm_dev_init()
recently added to drm-misc.

See the very nice example in drivers/gu/drm/drm_drv.c
(only in drm-misc-next for now)

> +	struct drm_plane primary;
> +	struct drm_crtc crtc;
> +	struct drm_encoder encoder;
> +};
> +
> +
> +static int ingenic_drm_probe(struct platform_device *pdev)
> +{
> +	const struct jz_soc_info *soc_info;
> +	struct device *dev = &pdev->dev;
> +	struct ingenic_drm *priv;
> +	struct clk *parent_clk;
> +	struct drm_bridge *bridge;
> +	struct drm_panel *panel;
> +	struct drm_device *drm;
> +	struct resource *mem;
> +	void __iomem *base;
> +	long parent_rate;
> +	int ret, irq;
> +
> +	soc_info = device_get_match_data(dev);
Everyone else uses of_device_... here. You should most
likely do the same.

> +	if (!soc_info)
> +		return -EINVAL;
Also, consider to print an error here.

> +
> +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> +	if (!priv)
> +		return -ENOMEM;
Use of devm_kzalloc() here is not good. See driver example in drm_drv.c

> +
> +	priv->dev = dev;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	priv->base = base = devm_ioremap_resource(dev, mem);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_err(dev, "Failed to get platform irq\n");
> +		return -ENOENT;
> +	}
> +
> +	priv->map = devm_regmap_init_mmio(dev, base,
> +					  &ingenic_drm_regmap_config);
> +	if (IS_ERR(priv->map)) {
> +		dev_err(dev, "Failed to create regmap\n");
> +		return PTR_ERR(priv->map);
> +	}
> +
> +	if (soc_info->needs_dev_clk) {
> +		priv->lcd_clk = devm_clk_get(dev, "lcd");
> +		if (IS_ERR(priv->lcd_clk)) {
> +			dev_err(dev, "Failed to get lcd clock\n");
> +			return PTR_ERR(priv->lcd_clk);
> +		}
> +	}
> +
> +	priv->pix_clk = devm_clk_get(dev, "lcd_pclk");
> +	if (IS_ERR(priv->pix_clk)) {
> +		dev_err(dev, "Failed to get pixel clock\n");
> +		return PTR_ERR(priv->pix_clk);
> +	}
> +
> +	ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &panel, &bridge);
> +	if (ret) {
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "Failed to get panel handle\n");
> +		return ret;
> +	}
> +
> +	if (panel) {
> +		bridge = devm_drm_panel_bridge_add(dev, panel,
> +						   DRM_MODE_CONNECTOR_Unknown);
> +	}
> +
> +	device_property_read_u32(dev, "ingenic,lcd-mode", &priv->lcd_mode);
> +
> +	priv->framedesc = dma_alloc_coherent(dev, sizeof(*priv->framedesc),
> +					     &priv->framedesc_phys, GFP_KERNEL);
> +	if (!priv->framedesc)
> +		return -ENOMEM;
> +
> +	priv->framedesc->next = priv->framedesc_phys;
> +	priv->framedesc->id = 0xdeafbead;
> +
> +	drm = drm_dev_alloc(&ingenic_drm_driver_data, dev);
> +	if (IS_ERR(drm)) {
> +		ret = PTR_ERR(drm);
> +		goto err_free_dma;
> +	}
> +
> +	priv->drm = drm;
> +
> +	drm_mode_config_init(drm);
> +	drm->mode_config.min_width = 0;
> +	drm->mode_config.min_height = 0;
> +	drm->mode_config.max_width = 800;
> +	drm->mode_config.max_height = 600;
> +	drm->mode_config.funcs = &ingenic_drm_mode_config_funcs;
> +
> +	drm_plane_helper_add(&priv->primary, &ingenic_drm_plane_helper_funcs);
> +
> +	ret = drm_universal_plane_init(drm, &priv->primary,
> +				       0, &ingenic_drm_primary_plane_funcs,
> +				       ingenic_drm_primary_formats,
> +				       ARRAY_SIZE(ingenic_drm_primary_formats),
> +				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
> +	if (ret) {
> +		dev_err(dev, "Failed to register primary plane: %i\n", ret);
> +		goto err_unref_drm;
> +	}
> +
> +	drm_crtc_helper_add(&priv->crtc, &ingenic_drm_crtc_helper_funcs);
> +
> +	ret = drm_crtc_init_with_planes(drm, &priv->crtc, &priv->primary,
> +					NULL, &ingenic_drm_crtc_funcs, NULL);
> +	if (ret) {
> +		dev_err(dev, "Failed to init CRTC: %i\n", ret);
> +		goto err_cleanup_plane;
> +	}
> +
> +	priv->encoder.possible_crtcs = 1;
> +
> +	drm_encoder_helper_add(&priv->encoder,
> +			       &ingenic_drm_encoder_helper_funcs);
> +
> +	ret = drm_encoder_init(drm, &priv->encoder, &ingenic_drm_encoder_funcs,
> +			       DRM_MODE_ENCODER_DPI, NULL);
> +	if (ret) {
> +		dev_err(dev, "Failed to init encoder: %i\n", ret);
> +		goto err_cleanup_crtc;
> +	}
> +
> +	ret = drm_bridge_attach(&priv->encoder, bridge, NULL);
> +	if (ret) {
> +		dev_err(dev, "Unable to attach bridge\n");
> +		goto err_cleanup_encoder;
> +	}
> +
> +	platform_set_drvdata(pdev, drm);
> +	priv->drm = drm;
> +	drm->dev_private = priv;
> +
> +	ret = drm_irq_install(drm, irq);
> +	if (ret) {
> +		dev_err(dev, "Unable to install IRQ handler\n");
> +		goto err_cleanup_encoder;
> +	}
> +
> +	ret = drm_vblank_init(drm, 1);
> +	if (ret) {
> +		dev_err(dev, "Failed calling drm_vblank_init()\n");
> +		goto err_uninstall_irq;
> +	}
> +
> +	drm_mode_config_reset(drm);
> +
> +	ret = clk_prepare_enable(priv->pix_clk);
> +	if (ret) {
> +		dev_err(dev, "Unable to start pixel clock\n");
> +		goto err_uninstall_irq;
> +	}
> +
> +	if (priv->lcd_clk) {
> +		parent_clk = clk_get_parent(priv->lcd_clk);
> +		parent_rate = clk_get_rate(parent_clk);
> +
> +		/* LCD Device clock must be 3x the pixel clock for STN panels,
> +		 * or 1.5x the pixel clock for TFT panels. To avoid having to
> +		 * check for the LCD device clock everytime we do a mode change,
> +		 * we set the LCD device clock to the highest rate possible.
> +		 */
> +		ret = clk_set_rate(priv->lcd_clk, parent_rate);
> +		if (ret) {
> +			dev_err(dev, "Unable to set LCD clock rate\n");
> +			goto err_pixclk_disable;
> +		}
> +
> +		ret = clk_prepare_enable(priv->lcd_clk);
> +		if (ret) {
> +			dev_err(dev, "Unable to start lcd clock\n");
> +			goto err_pixclk_disable;
> +		}
> +	}
> +
> +	ret = drm_fbdev_generic_setup(drm, 16);
> +	if (ret) {
> +		dev_err(dev, "Failed to init fbdev\n");
> +		goto err_devclk_disable;
> +	}
fbdev is usually considered an optionl feature that do not prevent
the display driver from loading.
Consider what to do in the error case.

_______________________________________________
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dri-devel@lists.freedesktop.org
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Re: [PATCH v2 3/3] DRM: Add KMS driver for the Ingenic JZ47xx SoCs

[Paul Cercueil]

Hi Sam,

Le sam. 16 mars 2019 à 22:59, Sam Ravnborg <sam@ravnborg.org> a écrit 
:
> Hi Paul.
> 
> Thanks for the v2 submission.
> 
> Did you analyze the possibility to utilize 
> drm_simple_display_pipe_init()
> and the related infrastructure?
> If this fits it should simplify the driver.
> If it does not fit please let us know why.
> As this is a one crtc / one connector / one panel the drm_simple_*
> infrastructure is supposed to be a good fit.

In the current state of the driver it would be possible to use the
drm_simple_display_pipe stuff, yes. However the SoCs support multiple
planes, and multiple outputs, and the plan is to upload the driver
to support these.

> Some smaller comments in the following.
> Most are suggestion, do not follow these blindly.

Ok, thanks.

Regards,
-Paul

> 	Sam
> 
>>  Add a KMS driver for the Ingenic JZ47xx family of SoCs.
>>  This driver is meant to replace the aging jz4740-fb driver.
>> 
>>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>>  Tested-by: Artur Rojek <contact@artur-rojek.eu>
> 
>>  +struct ingenic_drm {
>>  +	struct device *dev;
>>  +	void __iomem *base;
>>  +	struct regmap *map;
>>  +	struct clk *lcd_clk, *pix_clk;
>>  +
>>  +	u32 lcd_mode;
>>  +
>>  +	struct ingenic_dma_hwdesc *framedesc;
> 
> Consider the name "dma_hwdesc" for this.
> The struct is named so, which give a good indication
> this is a more descriptive name.
> 
> That said, the current solution looks much cleaner than the
> previous one.
> 
>>  +	dma_addr_t framedesc_phys;
> Likewise.
> 
> 
>>  +
>>  +	struct drm_device *drm;
> If drm is embedded you can use devm_drm_dev_init()
> recently added to drm-misc.
> 
> See the very nice example in drivers/gu/drm/drm_drv.c
> (only in drm-misc-next for now)
> 
>>  +	struct drm_plane primary;
>>  +	struct drm_crtc crtc;
>>  +	struct drm_encoder encoder;
>>  +};
>>  +
>>  +
>>  +static int ingenic_drm_probe(struct platform_device *pdev)
>>  +{
>>  +	const struct jz_soc_info *soc_info;
>>  +	struct device *dev = &pdev->dev;
>>  +	struct ingenic_drm *priv;
>>  +	struct clk *parent_clk;
>>  +	struct drm_bridge *bridge;
>>  +	struct drm_panel *panel;
>>  +	struct drm_device *drm;
>>  +	struct resource *mem;
>>  +	void __iomem *base;
>>  +	long parent_rate;
>>  +	int ret, irq;
>>  +
>>  +	soc_info = device_get_match_data(dev);
> Everyone else uses of_device_... here. You should most
> likely do the same.
> 
>>  +	if (!soc_info)
>>  +		return -EINVAL;
> Also, consider to print an error here.
> 
>>  +
>>  +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>>  +	if (!priv)
>>  +		return -ENOMEM;
> Use of devm_kzalloc() here is not good. See driver example in 
> drm_drv.c
> 
>>  +
>>  +	priv->dev = dev;
>>  +
>>  +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>  +	priv->base = base = devm_ioremap_resource(dev, mem);
>>  +	if (IS_ERR(base))
>>  +		return PTR_ERR(base);
>>  +
>>  +	irq = platform_get_irq(pdev, 0);
>>  +	if (irq < 0) {
>>  +		dev_err(dev, "Failed to get platform irq\n");
>>  +		return -ENOENT;
>>  +	}
>>  +
>>  +	priv->map = devm_regmap_init_mmio(dev, base,
>>  +					  &ingenic_drm_regmap_config);
>>  +	if (IS_ERR(priv->map)) {
>>  +		dev_err(dev, "Failed to create regmap\n");
>>  +		return PTR_ERR(priv->map);
>>  +	}
>>  +
>>  +	if (soc_info->needs_dev_clk) {
>>  +		priv->lcd_clk = devm_clk_get(dev, "lcd");
>>  +		if (IS_ERR(priv->lcd_clk)) {
>>  +			dev_err(dev, "Failed to get lcd clock\n");
>>  +			return PTR_ERR(priv->lcd_clk);
>>  +		}
>>  +	}
>>  +
>>  +	priv->pix_clk = devm_clk_get(dev, "lcd_pclk");
>>  +	if (IS_ERR(priv->pix_clk)) {
>>  +		dev_err(dev, "Failed to get pixel clock\n");
>>  +		return PTR_ERR(priv->pix_clk);
>>  +	}
>>  +
>>  +	ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &panel, 
>> &bridge);
>>  +	if (ret) {
>>  +		if (ret != -EPROBE_DEFER)
>>  +			dev_err(dev, "Failed to get panel handle\n");
>>  +		return ret;
>>  +	}
>>  +
>>  +	if (panel) {
>>  +		bridge = devm_drm_panel_bridge_add(dev, panel,
>>  +						   DRM_MODE_CONNECTOR_Unknown);
>>  +	}
>>  +
>>  +	device_property_read_u32(dev, "ingenic,lcd-mode", 
>> &priv->lcd_mode);
>>  +
>>  +	priv->framedesc = dma_alloc_coherent(dev, 
>> sizeof(*priv->framedesc),
>>  +					     &priv->framedesc_phys, GFP_KERNEL);
>>  +	if (!priv->framedesc)
>>  +		return -ENOMEM;
>>  +
>>  +	priv->framedesc->next = priv->framedesc_phys;
>>  +	priv->framedesc->id = 0xdeafbead;
>>  +
>>  +	drm = drm_dev_alloc(&ingenic_drm_driver_data, dev);
>>  +	if (IS_ERR(drm)) {
>>  +		ret = PTR_ERR(drm);
>>  +		goto err_free_dma;
>>  +	}
>>  +
>>  +	priv->drm = drm;
>>  +
>>  +	drm_mode_config_init(drm);
>>  +	drm->mode_config.min_width = 0;
>>  +	drm->mode_config.min_height = 0;
>>  +	drm->mode_config.max_width = 800;
>>  +	drm->mode_config.max_height = 600;
>>  +	drm->mode_config.funcs = &ingenic_drm_mode_config_funcs;
>>  +
>>  +	drm_plane_helper_add(&priv->primary, 
>> &ingenic_drm_plane_helper_funcs);
>>  +
>>  +	ret = drm_universal_plane_init(drm, &priv->primary,
>>  +				       0, &ingenic_drm_primary_plane_funcs,
>>  +				       ingenic_drm_primary_formats,
>>  +				       ARRAY_SIZE(ingenic_drm_primary_formats),
>>  +				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to register primary plane: %i\n", ret);
>>  +		goto err_unref_drm;
>>  +	}
>>  +
>>  +	drm_crtc_helper_add(&priv->crtc, &ingenic_drm_crtc_helper_funcs);
>>  +
>>  +	ret = drm_crtc_init_with_planes(drm, &priv->crtc, &priv->primary,
>>  +					NULL, &ingenic_drm_crtc_funcs, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to init CRTC: %i\n", ret);
>>  +		goto err_cleanup_plane;
>>  +	}
>>  +
>>  +	priv->encoder.possible_crtcs = 1;
>>  +
>>  +	drm_encoder_helper_add(&priv->encoder,
>>  +			       &ingenic_drm_encoder_helper_funcs);
>>  +
>>  +	ret = drm_encoder_init(drm, &priv->encoder, 
>> &ingenic_drm_encoder_funcs,
>>  +			       DRM_MODE_ENCODER_DPI, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to init encoder: %i\n", ret);
>>  +		goto err_cleanup_crtc;
>>  +	}
>>  +
>>  +	ret = drm_bridge_attach(&priv->encoder, bridge, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Unable to attach bridge\n");
>>  +		goto err_cleanup_encoder;
>>  +	}
>>  +
>>  +	platform_set_drvdata(pdev, drm);
>>  +	priv->drm = drm;
>>  +	drm->dev_private = priv;
>>  +
>>  +	ret = drm_irq_install(drm, irq);
>>  +	if (ret) {
>>  +		dev_err(dev, "Unable to install IRQ handler\n");
>>  +		goto err_cleanup_encoder;
>>  +	}
>>  +
>>  +	ret = drm_vblank_init(drm, 1);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed calling drm_vblank_init()\n");
>>  +		goto err_uninstall_irq;
>>  +	}
>>  +
>>  +	drm_mode_config_reset(drm);
>>  +
>>  +	ret = clk_prepare_enable(priv->pix_clk);
>>  +	if (ret) {
>>  +		dev_err(dev, "Unable to start pixel clock\n");
>>  +		goto err_uninstall_irq;
>>  +	}
>>  +
>>  +	if (priv->lcd_clk) {
>>  +		parent_clk = clk_get_parent(priv->lcd_clk);
>>  +		parent_rate = clk_get_rate(parent_clk);
>>  +
>>  +		/* LCD Device clock must be 3x the pixel clock for STN panels,
>>  +		 * or 1.5x the pixel clock for TFT panels. To avoid having to
>>  +		 * check for the LCD device clock everytime we do a mode change,
>>  +		 * we set the LCD device clock to the highest rate possible.
>>  +		 */
>>  +		ret = clk_set_rate(priv->lcd_clk, parent_rate);
>>  +		if (ret) {
>>  +			dev_err(dev, "Unable to set LCD clock rate\n");
>>  +			goto err_pixclk_disable;
>>  +		}
>>  +
>>  +		ret = clk_prepare_enable(priv->lcd_clk);
>>  +		if (ret) {
>>  +			dev_err(dev, "Unable to start lcd clock\n");
>>  +			goto err_pixclk_disable;
>>  +		}
>>  +	}
>>  +
>>  +	ret = drm_fbdev_generic_setup(drm, 16);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to init fbdev\n");
>>  +		goto err_devclk_disable;
>>  +	}
> fbdev is usually considered an optionl feature that do not prevent
> the display driver from loading.
> Consider what to do in the error case.
> 

Re: [PATCH v2 3/3] DRM: Add KMS driver for the Ingenic JZ47xx SoCs

[Paul Cercueil]

Hi Sam,

Le sam. 16 mars 2019 à 22:59, Sam Ravnborg <sam@ravnborg.org> a écrit 
:
> Hi Paul.
> 
> Thanks for the v2 submission.
> 
> Did you analyze the possibility to utilize 
> drm_simple_display_pipe_init()
> and the related infrastructure?
> If this fits it should simplify the driver.
> If it does not fit please let us know why.
> As this is a one crtc / one connector / one panel the drm_simple_*
> infrastructure is supposed to be a good fit.
> 
> Some smaller comments in the following.
> Most are suggestion, do not follow these blindly.
> 
> 	Sam
> 
>>  Add a KMS driver for the Ingenic JZ47xx family of SoCs.
>>  This driver is meant to replace the aging jz4740-fb driver.
>> 
>>  Signed-off-by: Paul Cercueil <paul@crapouillou.net>
>>  Tested-by: Artur Rojek <contact@artur-rojek.eu>
> 
>>  +struct ingenic_drm {
>>  +	struct device *dev;
>>  +	void __iomem *base;
>>  +	struct regmap *map;
>>  +	struct clk *lcd_clk, *pix_clk;
>>  +
>>  +	u32 lcd_mode;
>>  +
>>  +	struct ingenic_dma_hwdesc *framedesc;
> 
> Consider the name "dma_hwdesc" for this.
> The struct is named so, which give a good indication
> this is a more descriptive name.
> 
> That said, the current solution looks much cleaner than the
> previous one.
> 
>>  +	dma_addr_t framedesc_phys;
> Likewise.
> 
> 
>>  +
>>  +	struct drm_device *drm;
> If drm is embedded you can use devm_drm_dev_init()
> recently added to drm-misc.
> 
> See the very nice example in drivers/gu/drm/drm_drv.c
> (only in drm-misc-next for now)

If I have a request for deferred probe after devm_drm_dev_init(),
I get a kernel oops in drm_mode_config_cleanup()...

>>  +	struct drm_plane primary;
>>  +	struct drm_crtc crtc;
>>  +	struct drm_encoder encoder;
>>  +};
>>  +
>>  +
>>  +static int ingenic_drm_probe(struct platform_device *pdev)
>>  +{
>>  +	const struct jz_soc_info *soc_info;
>>  +	struct device *dev = &pdev->dev;
>>  +	struct ingenic_drm *priv;
>>  +	struct clk *parent_clk;
>>  +	struct drm_bridge *bridge;
>>  +	struct drm_panel *panel;
>>  +	struct drm_device *drm;
>>  +	struct resource *mem;
>>  +	void __iomem *base;
>>  +	long parent_rate;
>>  +	int ret, irq;
>>  +
>>  +	soc_info = device_get_match_data(dev);
> Everyone else uses of_device_... here. You should most
> likely do the same.
> 
>>  +	if (!soc_info)
>>  +		return -EINVAL;
> Also, consider to print an error here.
> 
>>  +
>>  +	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
>>  +	if (!priv)
>>  +		return -ENOMEM;
> Use of devm_kzalloc() here is not good. See driver example in 
> drm_drv.c
> 
>>  +
>>  +	priv->dev = dev;
>>  +
>>  +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
>>  +	priv->base = base = devm_ioremap_resource(dev, mem);
>>  +	if (IS_ERR(base))
>>  +		return PTR_ERR(base);
>>  +
>>  +	irq = platform_get_irq(pdev, 0);
>>  +	if (irq < 0) {
>>  +		dev_err(dev, "Failed to get platform irq\n");
>>  +		return -ENOENT;
>>  +	}
>>  +
>>  +	priv->map = devm_regmap_init_mmio(dev, base,
>>  +					  &ingenic_drm_regmap_config);
>>  +	if (IS_ERR(priv->map)) {
>>  +		dev_err(dev, "Failed to create regmap\n");
>>  +		return PTR_ERR(priv->map);
>>  +	}
>>  +
>>  +	if (soc_info->needs_dev_clk) {
>>  +		priv->lcd_clk = devm_clk_get(dev, "lcd");
>>  +		if (IS_ERR(priv->lcd_clk)) {
>>  +			dev_err(dev, "Failed to get lcd clock\n");
>>  +			return PTR_ERR(priv->lcd_clk);
>>  +		}
>>  +	}
>>  +
>>  +	priv->pix_clk = devm_clk_get(dev, "lcd_pclk");
>>  +	if (IS_ERR(priv->pix_clk)) {
>>  +		dev_err(dev, "Failed to get pixel clock\n");
>>  +		return PTR_ERR(priv->pix_clk);
>>  +	}
>>  +
>>  +	ret = drm_of_find_panel_or_bridge(dev->of_node, 0, 0, &panel, 
>> &bridge);
>>  +	if (ret) {
>>  +		if (ret != -EPROBE_DEFER)
>>  +			dev_err(dev, "Failed to get panel handle\n");
>>  +		return ret;
>>  +	}
>>  +
>>  +	if (panel) {
>>  +		bridge = devm_drm_panel_bridge_add(dev, panel,
>>  +						   DRM_MODE_CONNECTOR_Unknown);
>>  +	}
>>  +
>>  +	device_property_read_u32(dev, "ingenic,lcd-mode", 
>> &priv->lcd_mode);
>>  +
>>  +	priv->framedesc = dma_alloc_coherent(dev, 
>> sizeof(*priv->framedesc),
>>  +					     &priv->framedesc_phys, GFP_KERNEL);
>>  +	if (!priv->framedesc)
>>  +		return -ENOMEM;
>>  +
>>  +	priv->framedesc->next = priv->framedesc_phys;
>>  +	priv->framedesc->id = 0xdeafbead;
>>  +
>>  +	drm = drm_dev_alloc(&ingenic_drm_driver_data, dev);
>>  +	if (IS_ERR(drm)) {
>>  +		ret = PTR_ERR(drm);
>>  +		goto err_free_dma;
>>  +	}
>>  +
>>  +	priv->drm = drm;
>>  +
>>  +	drm_mode_config_init(drm);
>>  +	drm->mode_config.min_width = 0;
>>  +	drm->mode_config.min_height = 0;
>>  +	drm->mode_config.max_width = 800;
>>  +	drm->mode_config.max_height = 600;
>>  +	drm->mode_config.funcs = &ingenic_drm_mode_config_funcs;
>>  +
>>  +	drm_plane_helper_add(&priv->primary, 
>> &ingenic_drm_plane_helper_funcs);
>>  +
>>  +	ret = drm_universal_plane_init(drm, &priv->primary,
>>  +				       0, &ingenic_drm_primary_plane_funcs,
>>  +				       ingenic_drm_primary_formats,
>>  +				       ARRAY_SIZE(ingenic_drm_primary_formats),
>>  +				       NULL, DRM_PLANE_TYPE_PRIMARY, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to register primary plane: %i\n", ret);
>>  +		goto err_unref_drm;
>>  +	}
>>  +
>>  +	drm_crtc_helper_add(&priv->crtc, &ingenic_drm_crtc_helper_funcs);
>>  +
>>  +	ret = drm_crtc_init_with_planes(drm, &priv->crtc, &priv->primary,
>>  +					NULL, &ingenic_drm_crtc_funcs, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to init CRTC: %i\n", ret);
>>  +		goto err_cleanup_plane;
>>  +	}
>>  +
>>  +	priv->encoder.possible_crtcs = 1;
>>  +
>>  +	drm_encoder_helper_add(&priv->encoder,
>>  +			       &ingenic_drm_encoder_helper_funcs);
>>  +
>>  +	ret = drm_encoder_init(drm, &priv->encoder, 
>> &ingenic_drm_encoder_funcs,
>>  +			       DRM_MODE_ENCODER_DPI, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to init encoder: %i\n", ret);
>>  +		goto err_cleanup_crtc;
>>  +	}
>>  +
>>  +	ret = drm_bridge_attach(&priv->encoder, bridge, NULL);
>>  +	if (ret) {
>>  +		dev_err(dev, "Unable to attach bridge\n");
>>  +		goto err_cleanup_encoder;
>>  +	}
>>  +
>>  +	platform_set_drvdata(pdev, drm);
>>  +	priv->drm = drm;
>>  +	drm->dev_private = priv;
>>  +
>>  +	ret = drm_irq_install(drm, irq);
>>  +	if (ret) {
>>  +		dev_err(dev, "Unable to install IRQ handler\n");
>>  +		goto err_cleanup_encoder;
>>  +	}
>>  +
>>  +	ret = drm_vblank_init(drm, 1);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed calling drm_vblank_init()\n");
>>  +		goto err_uninstall_irq;
>>  +	}
>>  +
>>  +	drm_mode_config_reset(drm);
>>  +
>>  +	ret = clk_prepare_enable(priv->pix_clk);
>>  +	if (ret) {
>>  +		dev_err(dev, "Unable to start pixel clock\n");
>>  +		goto err_uninstall_irq;
>>  +	}
>>  +
>>  +	if (priv->lcd_clk) {
>>  +		parent_clk = clk_get_parent(priv->lcd_clk);
>>  +		parent_rate = clk_get_rate(parent_clk);
>>  +
>>  +		/* LCD Device clock must be 3x the pixel clock for STN panels,
>>  +		 * or 1.5x the pixel clock for TFT panels. To avoid having to
>>  +		 * check for the LCD device clock everytime we do a mode change,
>>  +		 * we set the LCD device clock to the highest rate possible.
>>  +		 */
>>  +		ret = clk_set_rate(priv->lcd_clk, parent_rate);
>>  +		if (ret) {
>>  +			dev_err(dev, "Unable to set LCD clock rate\n");
>>  +			goto err_pixclk_disable;
>>  +		}
>>  +
>>  +		ret = clk_prepare_enable(priv->lcd_clk);
>>  +		if (ret) {
>>  +			dev_err(dev, "Unable to start lcd clock\n");
>>  +			goto err_pixclk_disable;
>>  +		}
>>  +	}
>>  +
>>  +	ret = drm_fbdev_generic_setup(drm, 16);
>>  +	if (ret) {
>>  +		dev_err(dev, "Failed to init fbdev\n");
>>  +		goto err_devclk_disable;
>>  +	}
> fbdev is usually considered an optionl feature that do not prevent
> the display driver from loading.
> Consider what to do in the error case.
> 

Re: [PATCH v2 3/3] DRM: Add KMS driver for the Ingenic JZ47xx SoCs

[Daniel Vetter]

On Sat, Mar 16, 2019 at 10:59:44PM +0100, Sam Ravnborg wrote:
> > +	ret = drm_fbdev_generic_setup(drm, 16);
> > +	if (ret) {
> > +		dev_err(dev, "Failed to init fbdev\n");
> > +		goto err_devclk_disable;
> > +	}
> fbdev is usually considered an optionl feature that do not prevent
> the display driver from loading.
> Consider what to do in the error case.

Drive-through comment: Totally ok to require this, failing here usually
means you have a driver bug somewhere. fbdev is optional as in Kconfig
optional, but people who enable it generally need it.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch