1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2015 Free Electrons 4 * Copyright (C) 2015 NextThing Co 5 * 6 * Maxime Ripard <maxime.ripard@free-electrons.com> 7 */ 8 9 #include <linux/clk.h> 10 11 #include <drm/drm_atomic_helper.h> 12 #include <drm/drm_bridge.h> 13 #include <drm/drm_of.h> 14 #include <drm/drm_panel.h> 15 #include <drm/drm_print.h> 16 #include <drm/drm_probe_helper.h> 17 #include <drm/drm_simple_kms_helper.h> 18 19 #include "sun4i_crtc.h" 20 #include "sun4i_tcon.h" 21 #include "sun4i_rgb.h" 22 23 struct sun4i_rgb { 24 struct drm_connector connector; 25 struct drm_encoder encoder; 26 27 struct sun4i_tcon *tcon; 28 struct drm_panel *panel; 29 struct drm_bridge *bridge; 30 }; 31 32 static inline struct sun4i_rgb * 33 drm_connector_to_sun4i_rgb(struct drm_connector *connector) 34 { 35 return container_of(connector, struct sun4i_rgb, 36 connector); 37 } 38 39 static inline struct sun4i_rgb * 40 drm_encoder_to_sun4i_rgb(struct drm_encoder *encoder) 41 { 42 return container_of(encoder, struct sun4i_rgb, 43 encoder); 44 } 45 46 static int sun4i_rgb_get_modes(struct drm_connector *connector) 47 { 48 struct sun4i_rgb *rgb = 49 drm_connector_to_sun4i_rgb(connector); 50 51 return drm_panel_get_modes(rgb->panel, connector); 52 } 53 54 /* 55 * VESA DMT defines a tolerance of 0.5% on the pixel clock, while the 56 * CVT spec reuses that tolerance in its examples, so it looks to be a 57 * good default tolerance for the EDID-based modes. Define it to 5 per 58 * mille to avoid floating point operations. 59 */ 60 #define SUN4I_RGB_DOTCLOCK_TOLERANCE_PER_MILLE 5 61 62 static enum drm_mode_status sun4i_rgb_mode_valid(struct drm_encoder *crtc, 63 const struct drm_display_mode *mode) 64 { 65 struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(crtc); 66 struct sun4i_tcon *tcon = rgb->tcon; 67 u32 hsync = mode->hsync_end - mode->hsync_start; 68 u32 vsync = mode->vsync_end - mode->vsync_start; 69 unsigned long long rate = mode->clock * 1000; 70 unsigned long long lowest, highest; 71 unsigned long long rounded_rate; 72 73 DRM_DEBUG_DRIVER("Validating modes...\n"); 74 75 if (hsync < 1) 76 return MODE_HSYNC_NARROW; 77 78 if (hsync > 0x3ff) 79 return MODE_HSYNC_WIDE; 80 81 if ((mode->hdisplay < 1) || (mode->htotal < 1)) 82 return MODE_H_ILLEGAL; 83 84 if ((mode->hdisplay > 0x7ff) || (mode->htotal > 0xfff)) 85 return MODE_BAD_HVALUE; 86 87 DRM_DEBUG_DRIVER("Horizontal parameters OK\n"); 88 89 if (vsync < 1) 90 return MODE_VSYNC_NARROW; 91 92 if (vsync > 0x3ff) 93 return MODE_VSYNC_WIDE; 94 95 if ((mode->vdisplay < 1) || (mode->vtotal < 1)) 96 return MODE_V_ILLEGAL; 97 98 if ((mode->vdisplay > 0x7ff) || (mode->vtotal > 0xfff)) 99 return MODE_BAD_VVALUE; 100 101 DRM_DEBUG_DRIVER("Vertical parameters OK\n"); 102 103 /* 104 * TODO: We should use the struct display_timing if available 105 * and / or trying to stretch the timings within that 106 * tolerancy to take care of panels that we wouldn't be able 107 * to have a exact match for. 108 */ 109 if (rgb->panel) { 110 DRM_DEBUG_DRIVER("RGB panel used, skipping clock rate checks"); 111 goto out; 112 } 113 114 /* 115 * That shouldn't ever happen unless something is really wrong, but it 116 * doesn't harm to check. 117 */ 118 if (!rgb->bridge) 119 goto out; 120 121 tcon->dclk_min_div = 6; 122 tcon->dclk_max_div = 127; 123 rounded_rate = clk_round_rate(tcon->dclk, rate); 124 125 lowest = rate * (1000 - SUN4I_RGB_DOTCLOCK_TOLERANCE_PER_MILLE); 126 do_div(lowest, 1000); 127 if (rounded_rate < lowest) 128 return MODE_CLOCK_LOW; 129 130 highest = rate * (1000 + SUN4I_RGB_DOTCLOCK_TOLERANCE_PER_MILLE); 131 do_div(highest, 1000); 132 if (rounded_rate > highest) 133 return MODE_CLOCK_HIGH; 134 135 out: 136 DRM_DEBUG_DRIVER("Clock rate OK\n"); 137 138 return MODE_OK; 139 } 140 141 static const struct drm_connector_helper_funcs sun4i_rgb_con_helper_funcs = { 142 .get_modes = sun4i_rgb_get_modes, 143 }; 144 145 static void 146 sun4i_rgb_connector_destroy(struct drm_connector *connector) 147 { 148 drm_connector_cleanup(connector); 149 } 150 151 static const struct drm_connector_funcs sun4i_rgb_con_funcs = { 152 .fill_modes = drm_helper_probe_single_connector_modes, 153 .destroy = sun4i_rgb_connector_destroy, 154 .reset = drm_atomic_helper_connector_reset, 155 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, 156 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, 157 }; 158 159 static void sun4i_rgb_encoder_enable(struct drm_encoder *encoder) 160 { 161 struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder); 162 163 DRM_DEBUG_DRIVER("Enabling RGB output\n"); 164 165 if (rgb->panel) { 166 drm_panel_prepare(rgb->panel); 167 drm_panel_enable(rgb->panel); 168 } 169 } 170 171 static void sun4i_rgb_encoder_disable(struct drm_encoder *encoder) 172 { 173 struct sun4i_rgb *rgb = drm_encoder_to_sun4i_rgb(encoder); 174 175 DRM_DEBUG_DRIVER("Disabling RGB output\n"); 176 177 if (rgb->panel) { 178 drm_panel_disable(rgb->panel); 179 drm_panel_unprepare(rgb->panel); 180 } 181 } 182 183 static const struct drm_encoder_helper_funcs sun4i_rgb_enc_helper_funcs = { 184 .disable = sun4i_rgb_encoder_disable, 185 .enable = sun4i_rgb_encoder_enable, 186 .mode_valid = sun4i_rgb_mode_valid, 187 }; 188 189 int sun4i_rgb_init(struct drm_device *drm, struct sun4i_tcon *tcon) 190 { 191 struct drm_encoder *encoder; 192 struct sun4i_rgb *rgb; 193 int ret; 194 195 rgb = devm_kzalloc(drm->dev, sizeof(*rgb), GFP_KERNEL); 196 if (!rgb) 197 return -ENOMEM; 198 rgb->tcon = tcon; 199 encoder = &rgb->encoder; 200 201 ret = drm_of_find_panel_or_bridge(tcon->dev->of_node, 1, 0, 202 &rgb->panel, &rgb->bridge); 203 if (ret) { 204 dev_info(drm->dev, "No panel or bridge found... RGB output disabled\n"); 205 return 0; 206 } 207 208 drm_encoder_helper_add(&rgb->encoder, 209 &sun4i_rgb_enc_helper_funcs); 210 ret = drm_simple_encoder_init(drm, &rgb->encoder, 211 DRM_MODE_ENCODER_NONE); 212 if (ret) { 213 dev_err(drm->dev, "Couldn't initialise the rgb encoder\n"); 214 goto err_out; 215 } 216 217 /* The RGB encoder can only work with the TCON channel 0 */ 218 rgb->encoder.possible_crtcs = drm_crtc_mask(&tcon->crtc->crtc); 219 220 if (rgb->panel) { 221 drm_connector_helper_add(&rgb->connector, 222 &sun4i_rgb_con_helper_funcs); 223 ret = drm_connector_init(drm, &rgb->connector, 224 &sun4i_rgb_con_funcs, 225 DRM_MODE_CONNECTOR_Unknown); 226 if (ret) { 227 dev_err(drm->dev, "Couldn't initialise the rgb connector\n"); 228 goto err_cleanup_connector; 229 } 230 231 drm_connector_attach_encoder(&rgb->connector, 232 &rgb->encoder); 233 } 234 235 if (rgb->bridge) { 236 ret = drm_bridge_attach(encoder, rgb->bridge, NULL, 0); 237 if (ret) { 238 dev_err(drm->dev, "Couldn't attach our bridge\n"); 239 goto err_cleanup_connector; 240 } 241 } 242 243 return 0; 244 245 err_cleanup_connector: 246 drm_encoder_cleanup(&rgb->encoder); 247 err_out: 248 return ret; 249 } 250 EXPORT_SYMBOL(sun4i_rgb_init); 251