1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2020 Marek Vasut <marex@denx.de> 4 * 5 * Based on tc358764.c by 6 * Andrzej Hajda <a.hajda@samsung.com> 7 * Maciej Purski <m.purski@samsung.com> 8 * 9 * Based on rpi_touchscreen.c by 10 * Eric Anholt <eric@anholt.net> 11 */ 12 13 #include <linux/delay.h> 14 #include <linux/module.h> 15 #include <linux/of_graph.h> 16 #include <linux/regulator/consumer.h> 17 18 #include <video/mipi_display.h> 19 20 #include <drm/drm_atomic_helper.h> 21 #include <drm/drm_crtc.h> 22 #include <drm/drm_fb_helper.h> 23 #include <drm/drm_mipi_dsi.h> 24 #include <drm/drm_of.h> 25 #include <drm/drm_panel.h> 26 #include <drm/drm_print.h> 27 #include <drm/drm_probe_helper.h> 28 29 /* PPI layer registers */ 30 #define PPI_STARTPPI 0x0104 /* START control bit */ 31 #define PPI_LPTXTIMECNT 0x0114 /* LPTX timing signal */ 32 #define PPI_D0S_ATMR 0x0144 33 #define PPI_D1S_ATMR 0x0148 34 #define PPI_D0S_CLRSIPOCOUNT 0x0164 /* Assertion timer for Lane 0 */ 35 #define PPI_D1S_CLRSIPOCOUNT 0x0168 /* Assertion timer for Lane 1 */ 36 #define PPI_START_FUNCTION 1 37 38 /* DSI layer registers */ 39 #define DSI_STARTDSI 0x0204 /* START control bit of DSI-TX */ 40 #define DSI_LANEENABLE 0x0210 /* Enables each lane */ 41 #define DSI_RX_START 1 42 43 /* LCDC/DPI Host Registers */ 44 #define LCDCTRL 0x0420 45 46 /* SPI Master Registers */ 47 #define SPICMR 0x0450 48 #define SPITCR 0x0454 49 50 /* System Controller Registers */ 51 #define SYSCTRL 0x0464 52 53 /* System registers */ 54 #define LPX_PERIOD 3 55 56 /* Lane enable PPI and DSI register bits */ 57 #define LANEENABLE_CLEN BIT(0) 58 #define LANEENABLE_L0EN BIT(1) 59 #define LANEENABLE_L1EN BIT(2) 60 61 struct tc358762 { 62 struct device *dev; 63 struct drm_bridge bridge; 64 struct drm_connector connector; 65 struct regulator *regulator; 66 struct drm_bridge *panel_bridge; 67 bool pre_enabled; 68 int error; 69 }; 70 71 static int tc358762_clear_error(struct tc358762 *ctx) 72 { 73 int ret = ctx->error; 74 75 ctx->error = 0; 76 return ret; 77 } 78 79 static void tc358762_write(struct tc358762 *ctx, u16 addr, u32 val) 80 { 81 struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev); 82 ssize_t ret; 83 u8 data[6]; 84 85 if (ctx->error) 86 return; 87 88 data[0] = addr; 89 data[1] = addr >> 8; 90 data[2] = val; 91 data[3] = val >> 8; 92 data[4] = val >> 16; 93 data[5] = val >> 24; 94 95 ret = mipi_dsi_generic_write(dsi, data, sizeof(data)); 96 if (ret < 0) 97 ctx->error = ret; 98 } 99 100 static inline struct tc358762 *bridge_to_tc358762(struct drm_bridge *bridge) 101 { 102 return container_of(bridge, struct tc358762, bridge); 103 } 104 105 static int tc358762_init(struct tc358762 *ctx) 106 { 107 tc358762_write(ctx, DSI_LANEENABLE, 108 LANEENABLE_L0EN | LANEENABLE_CLEN); 109 tc358762_write(ctx, PPI_D0S_CLRSIPOCOUNT, 5); 110 tc358762_write(ctx, PPI_D1S_CLRSIPOCOUNT, 5); 111 tc358762_write(ctx, PPI_D0S_ATMR, 0); 112 tc358762_write(ctx, PPI_D1S_ATMR, 0); 113 tc358762_write(ctx, PPI_LPTXTIMECNT, LPX_PERIOD); 114 115 tc358762_write(ctx, SPICMR, 0x00); 116 tc358762_write(ctx, LCDCTRL, 0x00100150); 117 tc358762_write(ctx, SYSCTRL, 0x040f); 118 msleep(100); 119 120 tc358762_write(ctx, PPI_STARTPPI, PPI_START_FUNCTION); 121 tc358762_write(ctx, DSI_STARTDSI, DSI_RX_START); 122 123 msleep(100); 124 125 return tc358762_clear_error(ctx); 126 } 127 128 static void tc358762_post_disable(struct drm_bridge *bridge) 129 { 130 struct tc358762 *ctx = bridge_to_tc358762(bridge); 131 int ret; 132 133 /* 134 * The post_disable hook might be called multiple times. 135 * We want to avoid regulator imbalance below. 136 */ 137 if (!ctx->pre_enabled) 138 return; 139 140 ctx->pre_enabled = false; 141 142 ret = regulator_disable(ctx->regulator); 143 if (ret < 0) 144 dev_err(ctx->dev, "error disabling regulators (%d)\n", ret); 145 } 146 147 static void tc358762_pre_enable(struct drm_bridge *bridge) 148 { 149 struct tc358762 *ctx = bridge_to_tc358762(bridge); 150 int ret; 151 152 ret = regulator_enable(ctx->regulator); 153 if (ret < 0) 154 dev_err(ctx->dev, "error enabling regulators (%d)\n", ret); 155 156 ret = tc358762_init(ctx); 157 if (ret < 0) 158 dev_err(ctx->dev, "error initializing bridge (%d)\n", ret); 159 160 ctx->pre_enabled = true; 161 } 162 163 static int tc358762_attach(struct drm_bridge *bridge, 164 enum drm_bridge_attach_flags flags) 165 { 166 struct tc358762 *ctx = bridge_to_tc358762(bridge); 167 168 return drm_bridge_attach(bridge->encoder, ctx->panel_bridge, 169 bridge, flags); 170 } 171 172 static const struct drm_bridge_funcs tc358762_bridge_funcs = { 173 .post_disable = tc358762_post_disable, 174 .pre_enable = tc358762_pre_enable, 175 .attach = tc358762_attach, 176 }; 177 178 static int tc358762_parse_dt(struct tc358762 *ctx) 179 { 180 struct drm_bridge *panel_bridge; 181 struct device *dev = ctx->dev; 182 struct drm_panel *panel; 183 int ret; 184 185 ret = drm_of_find_panel_or_bridge(dev->of_node, 1, 0, &panel, NULL); 186 if (ret) 187 return ret; 188 189 panel_bridge = devm_drm_panel_bridge_add(dev, panel); 190 191 if (IS_ERR(panel_bridge)) 192 return PTR_ERR(panel_bridge); 193 194 ctx->panel_bridge = panel_bridge; 195 196 return 0; 197 } 198 199 static int tc358762_configure_regulators(struct tc358762 *ctx) 200 { 201 ctx->regulator = devm_regulator_get(ctx->dev, "vddc"); 202 if (IS_ERR(ctx->regulator)) 203 return PTR_ERR(ctx->regulator); 204 205 return 0; 206 } 207 208 static int tc358762_probe(struct mipi_dsi_device *dsi) 209 { 210 struct device *dev = &dsi->dev; 211 struct tc358762 *ctx; 212 int ret; 213 214 ctx = devm_kzalloc(dev, sizeof(struct tc358762), GFP_KERNEL); 215 if (!ctx) 216 return -ENOMEM; 217 218 mipi_dsi_set_drvdata(dsi, ctx); 219 220 ctx->dev = dev; 221 ctx->pre_enabled = false; 222 223 /* TODO: Find out how to get dual-lane mode working */ 224 dsi->lanes = 1; 225 dsi->format = MIPI_DSI_FMT_RGB888; 226 dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 227 MIPI_DSI_MODE_LPM; 228 229 ret = tc358762_parse_dt(ctx); 230 if (ret < 0) 231 return ret; 232 233 ret = tc358762_configure_regulators(ctx); 234 if (ret < 0) 235 return ret; 236 237 ctx->bridge.funcs = &tc358762_bridge_funcs; 238 ctx->bridge.type = DRM_MODE_CONNECTOR_DPI; 239 ctx->bridge.of_node = dev->of_node; 240 241 drm_bridge_add(&ctx->bridge); 242 243 ret = mipi_dsi_attach(dsi); 244 if (ret < 0) { 245 drm_bridge_remove(&ctx->bridge); 246 dev_err(dev, "failed to attach dsi\n"); 247 } 248 249 return ret; 250 } 251 252 static int tc358762_remove(struct mipi_dsi_device *dsi) 253 { 254 struct tc358762 *ctx = mipi_dsi_get_drvdata(dsi); 255 256 mipi_dsi_detach(dsi); 257 drm_bridge_remove(&ctx->bridge); 258 259 return 0; 260 } 261 262 static const struct of_device_id tc358762_of_match[] = { 263 { .compatible = "toshiba,tc358762" }, 264 { } 265 }; 266 MODULE_DEVICE_TABLE(of, tc358762_of_match); 267 268 static struct mipi_dsi_driver tc358762_driver = { 269 .probe = tc358762_probe, 270 .remove = tc358762_remove, 271 .driver = { 272 .name = "tc358762", 273 .of_match_table = tc358762_of_match, 274 }, 275 }; 276 module_mipi_dsi_driver(tc358762_driver); 277 278 MODULE_AUTHOR("Marek Vasut <marex@denx.de>"); 279 MODULE_DESCRIPTION("MIPI-DSI based Driver for TC358762 DSI/DPI Bridge"); 280 MODULE_LICENSE("GPL v2"); 281