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/mod_devicetable.h> 15 #include <linux/module.h> 16 #include <linux/of_graph.h> 17 #include <linux/regulator/consumer.h> 18 19 #include <video/mipi_display.h> 20 21 #include <drm/drm_atomic_helper.h> 22 #include <drm/drm_crtc.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 regulator *regulator; 65 struct drm_bridge *panel_bridge; 66 bool pre_enabled; 67 int error; 68 }; 69 70 static int tc358762_clear_error(struct tc358762 *ctx) 71 { 72 int ret = ctx->error; 73 74 ctx->error = 0; 75 return ret; 76 } 77 78 static void tc358762_write(struct tc358762 *ctx, u16 addr, u32 val) 79 { 80 struct mipi_dsi_device *dsi = to_mipi_dsi_device(ctx->dev); 81 ssize_t ret; 82 u8 data[6]; 83 84 if (ctx->error) 85 return; 86 87 data[0] = addr; 88 data[1] = addr >> 8; 89 data[2] = val; 90 data[3] = val >> 8; 91 data[4] = val >> 16; 92 data[5] = val >> 24; 93 94 ret = mipi_dsi_generic_write(dsi, data, sizeof(data)); 95 if (ret < 0) 96 ctx->error = ret; 97 } 98 99 static inline struct tc358762 *bridge_to_tc358762(struct drm_bridge *bridge) 100 { 101 return container_of(bridge, struct tc358762, bridge); 102 } 103 104 static int tc358762_init(struct tc358762 *ctx) 105 { 106 tc358762_write(ctx, DSI_LANEENABLE, 107 LANEENABLE_L0EN | LANEENABLE_CLEN); 108 tc358762_write(ctx, PPI_D0S_CLRSIPOCOUNT, 5); 109 tc358762_write(ctx, PPI_D1S_CLRSIPOCOUNT, 5); 110 tc358762_write(ctx, PPI_D0S_ATMR, 0); 111 tc358762_write(ctx, PPI_D1S_ATMR, 0); 112 tc358762_write(ctx, PPI_LPTXTIMECNT, LPX_PERIOD); 113 114 tc358762_write(ctx, SPICMR, 0x00); 115 tc358762_write(ctx, LCDCTRL, 0x00100150); 116 tc358762_write(ctx, SYSCTRL, 0x040f); 117 msleep(100); 118 119 tc358762_write(ctx, PPI_STARTPPI, PPI_START_FUNCTION); 120 tc358762_write(ctx, DSI_STARTDSI, DSI_RX_START); 121 122 msleep(100); 123 124 return tc358762_clear_error(ctx); 125 } 126 127 static void tc358762_post_disable(struct drm_bridge *bridge) 128 { 129 struct tc358762 *ctx = bridge_to_tc358762(bridge); 130 int ret; 131 132 /* 133 * The post_disable hook might be called multiple times. 134 * We want to avoid regulator imbalance below. 135 */ 136 if (!ctx->pre_enabled) 137 return; 138 139 ctx->pre_enabled = false; 140 141 ret = regulator_disable(ctx->regulator); 142 if (ret < 0) 143 dev_err(ctx->dev, "error disabling regulators (%d)\n", ret); 144 } 145 146 static void tc358762_pre_enable(struct drm_bridge *bridge) 147 { 148 struct tc358762 *ctx = bridge_to_tc358762(bridge); 149 int ret; 150 151 ret = regulator_enable(ctx->regulator); 152 if (ret < 0) 153 dev_err(ctx->dev, "error enabling regulators (%d)\n", ret); 154 155 ret = tc358762_init(ctx); 156 if (ret < 0) 157 dev_err(ctx->dev, "error initializing bridge (%d)\n", ret); 158 159 ctx->pre_enabled = true; 160 } 161 162 static int tc358762_attach(struct drm_bridge *bridge, 163 enum drm_bridge_attach_flags flags) 164 { 165 struct tc358762 *ctx = bridge_to_tc358762(bridge); 166 167 return drm_bridge_attach(bridge->encoder, ctx->panel_bridge, 168 bridge, flags); 169 } 170 171 static const struct drm_bridge_funcs tc358762_bridge_funcs = { 172 .post_disable = tc358762_post_disable, 173 .pre_enable = tc358762_pre_enable, 174 .attach = tc358762_attach, 175 }; 176 177 static int tc358762_parse_dt(struct tc358762 *ctx) 178 { 179 struct drm_bridge *panel_bridge; 180 struct device *dev = ctx->dev; 181 182 panel_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0); 183 if (IS_ERR(panel_bridge)) 184 return PTR_ERR(panel_bridge); 185 186 ctx->panel_bridge = panel_bridge; 187 188 return 0; 189 } 190 191 static int tc358762_configure_regulators(struct tc358762 *ctx) 192 { 193 ctx->regulator = devm_regulator_get(ctx->dev, "vddc"); 194 if (IS_ERR(ctx->regulator)) 195 return PTR_ERR(ctx->regulator); 196 197 return 0; 198 } 199 200 static int tc358762_probe(struct mipi_dsi_device *dsi) 201 { 202 struct device *dev = &dsi->dev; 203 struct tc358762 *ctx; 204 int ret; 205 206 ctx = devm_kzalloc(dev, sizeof(struct tc358762), GFP_KERNEL); 207 if (!ctx) 208 return -ENOMEM; 209 210 mipi_dsi_set_drvdata(dsi, ctx); 211 212 ctx->dev = dev; 213 ctx->pre_enabled = false; 214 215 /* TODO: Find out how to get dual-lane mode working */ 216 dsi->lanes = 1; 217 dsi->format = MIPI_DSI_FMT_RGB888; 218 dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_SYNC_PULSE | 219 MIPI_DSI_MODE_LPM; 220 221 ret = tc358762_parse_dt(ctx); 222 if (ret < 0) 223 return ret; 224 225 ret = tc358762_configure_regulators(ctx); 226 if (ret < 0) 227 return ret; 228 229 ctx->bridge.funcs = &tc358762_bridge_funcs; 230 ctx->bridge.type = DRM_MODE_CONNECTOR_DPI; 231 ctx->bridge.of_node = dev->of_node; 232 233 drm_bridge_add(&ctx->bridge); 234 235 ret = mipi_dsi_attach(dsi); 236 if (ret < 0) { 237 drm_bridge_remove(&ctx->bridge); 238 dev_err(dev, "failed to attach dsi\n"); 239 } 240 241 return ret; 242 } 243 244 static void tc358762_remove(struct mipi_dsi_device *dsi) 245 { 246 struct tc358762 *ctx = mipi_dsi_get_drvdata(dsi); 247 248 mipi_dsi_detach(dsi); 249 drm_bridge_remove(&ctx->bridge); 250 } 251 252 static const struct of_device_id tc358762_of_match[] = { 253 { .compatible = "toshiba,tc358762" }, 254 { } 255 }; 256 MODULE_DEVICE_TABLE(of, tc358762_of_match); 257 258 static struct mipi_dsi_driver tc358762_driver = { 259 .probe = tc358762_probe, 260 .remove = tc358762_remove, 261 .driver = { 262 .name = "tc358762", 263 .of_match_table = tc358762_of_match, 264 }, 265 }; 266 module_mipi_dsi_driver(tc358762_driver); 267 268 MODULE_AUTHOR("Marek Vasut <marex@denx.de>"); 269 MODULE_DESCRIPTION("MIPI-DSI based Driver for TC358762 DSI/DPI Bridge"); 270 MODULE_LICENSE("GPL v2"); 271