1 // SPDX-License-Identifier: GPL-2.0+
2 
3 /*
4  * Copyright (C) 2022 Pengutronix, Lucas Stach <kernel@pengutronix.de>
5  */
6 
7 #include <drm/drm_atomic_helper.h>
8 #include <drm/drm_bridge.h>
9 #include <drm/drm_crtc.h>
10 #include <linux/bitfield.h>
11 #include <linux/io.h>
12 #include <linux/module.h>
13 #include <linux/of.h>
14 #include <linux/of_graph.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 
18 #define HTX_PVI_CTRL			0x0
19 #define  PVI_CTRL_OP_VSYNC_POL		BIT(18)
20 #define  PVI_CTRL_OP_HSYNC_POL		BIT(17)
21 #define  PVI_CTRL_OP_DE_POL		BIT(16)
22 #define  PVI_CTRL_INP_VSYNC_POL		BIT(14)
23 #define  PVI_CTRL_INP_HSYNC_POL		BIT(13)
24 #define  PVI_CTRL_INP_DE_POL		BIT(12)
25 #define  PVI_CTRL_MODE_MASK		GENMASK(2, 1)
26 #define  PVI_CTRL_MODE_LCDIF		2
27 #define  PVI_CTRL_EN			BIT(0)
28 
29 struct imx8mp_hdmi_pvi {
30 	struct drm_bridge	bridge;
31 	struct device		*dev;
32 	struct drm_bridge	*next_bridge;
33 	void __iomem		*regs;
34 };
35 
36 static inline struct imx8mp_hdmi_pvi *
to_imx8mp_hdmi_pvi(struct drm_bridge * bridge)37 to_imx8mp_hdmi_pvi(struct drm_bridge *bridge)
38 {
39 	return container_of(bridge, struct imx8mp_hdmi_pvi, bridge);
40 }
41 
imx8mp_hdmi_pvi_bridge_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)42 static int imx8mp_hdmi_pvi_bridge_attach(struct drm_bridge *bridge,
43 					 enum drm_bridge_attach_flags flags)
44 {
45 	struct imx8mp_hdmi_pvi *pvi = to_imx8mp_hdmi_pvi(bridge);
46 
47 	return drm_bridge_attach(bridge->encoder, pvi->next_bridge,
48 				 bridge, flags);
49 }
50 
imx8mp_hdmi_pvi_bridge_enable(struct drm_bridge * bridge,struct drm_atomic_state * state)51 static void imx8mp_hdmi_pvi_bridge_enable(struct drm_bridge *bridge,
52 					  struct drm_atomic_state *state)
53 {
54 	struct imx8mp_hdmi_pvi *pvi = to_imx8mp_hdmi_pvi(bridge);
55 	struct drm_connector_state *conn_state;
56 	struct drm_bridge_state *bridge_state;
57 	const struct drm_display_mode *mode;
58 	struct drm_crtc_state *crtc_state;
59 	struct drm_connector *connector;
60 	u32 bus_flags = 0, val;
61 
62 	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
63 	connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
64 	conn_state = drm_atomic_get_new_connector_state(state, connector);
65 	crtc_state = drm_atomic_get_new_crtc_state(state, conn_state->crtc);
66 
67 	if (WARN_ON(pm_runtime_resume_and_get(pvi->dev)))
68 		return;
69 
70 	mode = &crtc_state->adjusted_mode;
71 
72 	val = FIELD_PREP(PVI_CTRL_MODE_MASK, PVI_CTRL_MODE_LCDIF) | PVI_CTRL_EN;
73 
74 	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
75 		val |= PVI_CTRL_OP_VSYNC_POL | PVI_CTRL_INP_VSYNC_POL;
76 
77 	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
78 		val |= PVI_CTRL_OP_HSYNC_POL | PVI_CTRL_INP_HSYNC_POL;
79 
80 	if (pvi->next_bridge->timings)
81 		bus_flags = pvi->next_bridge->timings->input_bus_flags;
82 	else if (bridge_state)
83 		bus_flags = bridge_state->input_bus_cfg.flags;
84 
85 	if (bus_flags & DRM_BUS_FLAG_DE_HIGH)
86 		val |= PVI_CTRL_OP_DE_POL | PVI_CTRL_INP_DE_POL;
87 
88 	writel(val, pvi->regs + HTX_PVI_CTRL);
89 }
90 
imx8mp_hdmi_pvi_bridge_disable(struct drm_bridge * bridge,struct drm_atomic_state * state)91 static void imx8mp_hdmi_pvi_bridge_disable(struct drm_bridge *bridge,
92 					   struct drm_atomic_state *state)
93 {
94 	struct imx8mp_hdmi_pvi *pvi = to_imx8mp_hdmi_pvi(bridge);
95 
96 	writel(0x0, pvi->regs + HTX_PVI_CTRL);
97 
98 	pm_runtime_put(pvi->dev);
99 }
100 
101 static u32 *
imx8mp_hdmi_pvi_bridge_get_input_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,u32 output_fmt,unsigned int * num_input_fmts)102 imx8mp_hdmi_pvi_bridge_get_input_bus_fmts(struct drm_bridge *bridge,
103 					  struct drm_bridge_state *bridge_state,
104 					  struct drm_crtc_state *crtc_state,
105 					  struct drm_connector_state *conn_state,
106 					  u32 output_fmt,
107 					  unsigned int *num_input_fmts)
108 {
109 	struct imx8mp_hdmi_pvi *pvi = to_imx8mp_hdmi_pvi(bridge);
110 	struct drm_bridge *next_bridge = pvi->next_bridge;
111 	struct drm_bridge_state *next_state;
112 
113 	if (!next_bridge->funcs->atomic_get_input_bus_fmts)
114 		return NULL;
115 
116 	next_state = drm_atomic_get_new_bridge_state(crtc_state->state,
117 						     next_bridge);
118 
119 	return next_bridge->funcs->atomic_get_input_bus_fmts(next_bridge,
120 							     next_state,
121 							     crtc_state,
122 							     conn_state,
123 							     output_fmt,
124 							     num_input_fmts);
125 }
126 
127 static const struct drm_bridge_funcs imx_hdmi_pvi_bridge_funcs = {
128 	.attach		= imx8mp_hdmi_pvi_bridge_attach,
129 	.atomic_enable	= imx8mp_hdmi_pvi_bridge_enable,
130 	.atomic_disable	= imx8mp_hdmi_pvi_bridge_disable,
131 	.atomic_get_input_bus_fmts = imx8mp_hdmi_pvi_bridge_get_input_bus_fmts,
132 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
133 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
134 	.atomic_reset = drm_atomic_helper_bridge_reset,
135 };
136 
imx8mp_hdmi_pvi_probe(struct platform_device * pdev)137 static int imx8mp_hdmi_pvi_probe(struct platform_device *pdev)
138 {
139 	struct device_node *remote;
140 	struct imx8mp_hdmi_pvi *pvi;
141 
142 	pvi = devm_kzalloc(&pdev->dev, sizeof(*pvi), GFP_KERNEL);
143 	if (!pvi)
144 		return -ENOMEM;
145 
146 	platform_set_drvdata(pdev, pvi);
147 	pvi->dev = &pdev->dev;
148 
149 	pvi->regs = devm_platform_ioremap_resource(pdev, 0);
150 	if (IS_ERR(pvi->regs))
151 		return PTR_ERR(pvi->regs);
152 
153 	/* Get the next bridge in the pipeline. */
154 	remote = of_graph_get_remote_node(pdev->dev.of_node, 1, -1);
155 	if (!remote)
156 		return -EINVAL;
157 
158 	pvi->next_bridge = of_drm_find_bridge(remote);
159 	of_node_put(remote);
160 
161 	if (!pvi->next_bridge)
162 		return dev_err_probe(&pdev->dev, -EPROBE_DEFER,
163 				     "could not find next bridge\n");
164 
165 	pm_runtime_enable(&pdev->dev);
166 
167 	/* Register the bridge. */
168 	pvi->bridge.funcs = &imx_hdmi_pvi_bridge_funcs;
169 	pvi->bridge.of_node = pdev->dev.of_node;
170 	pvi->bridge.timings = pvi->next_bridge->timings;
171 
172 	drm_bridge_add(&pvi->bridge);
173 
174 	return 0;
175 }
176 
imx8mp_hdmi_pvi_remove(struct platform_device * pdev)177 static void imx8mp_hdmi_pvi_remove(struct platform_device *pdev)
178 {
179 	struct imx8mp_hdmi_pvi *pvi = platform_get_drvdata(pdev);
180 
181 	drm_bridge_remove(&pvi->bridge);
182 
183 	pm_runtime_disable(&pdev->dev);
184 }
185 
186 static const struct of_device_id imx8mp_hdmi_pvi_match[] = {
187 	{
188 		.compatible = "fsl,imx8mp-hdmi-pvi",
189 	}, {
190 		/* sentinel */
191 	}
192 };
193 MODULE_DEVICE_TABLE(of, imx8mp_hdmi_pvi_match);
194 
195 static struct platform_driver imx8mp_hdmi_pvi_driver = {
196 	.probe	= imx8mp_hdmi_pvi_probe,
197 	.remove = imx8mp_hdmi_pvi_remove,
198 	.driver		= {
199 		.name = "imx-hdmi-pvi",
200 		.of_match_table	= imx8mp_hdmi_pvi_match,
201 	},
202 };
203 module_platform_driver(imx8mp_hdmi_pvi_driver);
204 
205 MODULE_DESCRIPTION("i.MX8MP HDMI TX Parallel Video Interface bridge driver");
206 MODULE_LICENSE("GPL");
207