1*0cad855fSPaul Burton /* 2*0cad855fSPaul Burton * Copyright (C) 2016 Imagination Technologies 3*0cad855fSPaul Burton * Author: Paul Burton <paul.burton@imgtec.com> 4*0cad855fSPaul Burton * 5*0cad855fSPaul Burton * This program is free software; you can redistribute it and/or modify it 6*0cad855fSPaul Burton * under the terms of the GNU General Public License as published by the 7*0cad855fSPaul Burton * Free Software Foundation; either version 2 of the License, or (at your 8*0cad855fSPaul Burton * option) any later version. 9*0cad855fSPaul Burton */ 10*0cad855fSPaul Burton 11*0cad855fSPaul Burton #include <generated/utsrelease.h> 12*0cad855fSPaul Burton #include <linux/kernel.h> 13*0cad855fSPaul Burton #include <linux/io.h> 14*0cad855fSPaul Burton #include <linux/mfd/syscon.h> 15*0cad855fSPaul Burton #include <linux/module.h> 16*0cad855fSPaul Burton #include <linux/of_address.h> 17*0cad855fSPaul Burton #include <linux/of_platform.h> 18*0cad855fSPaul Burton #include <linux/platform_device.h> 19*0cad855fSPaul Burton #include <linux/regmap.h> 20*0cad855fSPaul Burton #include <linux/slab.h> 21*0cad855fSPaul Burton #include <linux/sysfs.h> 22*0cad855fSPaul Burton 23*0cad855fSPaul Burton struct img_ascii_lcd_ctx; 24*0cad855fSPaul Burton 25*0cad855fSPaul Burton /** 26*0cad855fSPaul Burton * struct img_ascii_lcd_config - Configuration information about an LCD model 27*0cad855fSPaul Burton * @num_chars: the number of characters the LCD can display 28*0cad855fSPaul Burton * @external_regmap: true if registers are in a system controller, else false 29*0cad855fSPaul Burton * @update: function called to update the LCD 30*0cad855fSPaul Burton */ 31*0cad855fSPaul Burton struct img_ascii_lcd_config { 32*0cad855fSPaul Burton unsigned int num_chars; 33*0cad855fSPaul Burton bool external_regmap; 34*0cad855fSPaul Burton void (*update)(struct img_ascii_lcd_ctx *ctx); 35*0cad855fSPaul Burton }; 36*0cad855fSPaul Burton 37*0cad855fSPaul Burton /** 38*0cad855fSPaul Burton * struct img_ascii_lcd_ctx - Private data structure 39*0cad855fSPaul Burton * @pdev: the ASCII LCD platform device 40*0cad855fSPaul Burton * @base: the base address of the LCD registers 41*0cad855fSPaul Burton * @regmap: the regmap through which LCD registers are accessed 42*0cad855fSPaul Burton * @offset: the offset within regmap to the start of the LCD registers 43*0cad855fSPaul Burton * @cfg: pointer to the LCD model configuration 44*0cad855fSPaul Burton * @message: the full message to display or scroll on the LCD 45*0cad855fSPaul Burton * @message_len: the length of the @message string 46*0cad855fSPaul Burton * @scroll_pos: index of the first character of @message currently displayed 47*0cad855fSPaul Burton * @scroll_rate: scroll interval in jiffies 48*0cad855fSPaul Burton * @timer: timer used to implement scrolling 49*0cad855fSPaul Burton * @curr: the string currently displayed on the LCD 50*0cad855fSPaul Burton */ 51*0cad855fSPaul Burton struct img_ascii_lcd_ctx { 52*0cad855fSPaul Burton struct platform_device *pdev; 53*0cad855fSPaul Burton union { 54*0cad855fSPaul Burton void __iomem *base; 55*0cad855fSPaul Burton struct regmap *regmap; 56*0cad855fSPaul Burton }; 57*0cad855fSPaul Burton u32 offset; 58*0cad855fSPaul Burton const struct img_ascii_lcd_config *cfg; 59*0cad855fSPaul Burton char *message; 60*0cad855fSPaul Burton unsigned int message_len; 61*0cad855fSPaul Burton unsigned int scroll_pos; 62*0cad855fSPaul Burton unsigned int scroll_rate; 63*0cad855fSPaul Burton struct timer_list timer; 64*0cad855fSPaul Burton char curr[] __aligned(8); 65*0cad855fSPaul Burton }; 66*0cad855fSPaul Burton 67*0cad855fSPaul Burton /* 68*0cad855fSPaul Burton * MIPS Boston development board 69*0cad855fSPaul Burton */ 70*0cad855fSPaul Burton 71*0cad855fSPaul Burton static void boston_update(struct img_ascii_lcd_ctx *ctx) 72*0cad855fSPaul Burton { 73*0cad855fSPaul Burton ulong val; 74*0cad855fSPaul Burton 75*0cad855fSPaul Burton #if BITS_PER_LONG == 64 76*0cad855fSPaul Burton val = *((u64 *)&ctx->curr[0]); 77*0cad855fSPaul Burton __raw_writeq(val, ctx->base); 78*0cad855fSPaul Burton #elif BITS_PER_LONG == 32 79*0cad855fSPaul Burton val = *((u32 *)&ctx->curr[0]); 80*0cad855fSPaul Burton __raw_writel(val, ctx->base); 81*0cad855fSPaul Burton val = *((u32 *)&ctx->curr[4]); 82*0cad855fSPaul Burton __raw_writel(val, ctx->base + 4); 83*0cad855fSPaul Burton #else 84*0cad855fSPaul Burton # error Not 32 or 64 bit 85*0cad855fSPaul Burton #endif 86*0cad855fSPaul Burton } 87*0cad855fSPaul Burton 88*0cad855fSPaul Burton static struct img_ascii_lcd_config boston_config = { 89*0cad855fSPaul Burton .num_chars = 8, 90*0cad855fSPaul Burton .update = boston_update, 91*0cad855fSPaul Burton }; 92*0cad855fSPaul Burton 93*0cad855fSPaul Burton /* 94*0cad855fSPaul Burton * MIPS Malta development board 95*0cad855fSPaul Burton */ 96*0cad855fSPaul Burton 97*0cad855fSPaul Burton static void malta_update(struct img_ascii_lcd_ctx *ctx) 98*0cad855fSPaul Burton { 99*0cad855fSPaul Burton unsigned int i; 100*0cad855fSPaul Burton int err; 101*0cad855fSPaul Burton 102*0cad855fSPaul Burton for (i = 0; i < ctx->cfg->num_chars; i++) { 103*0cad855fSPaul Burton err = regmap_write(ctx->regmap, 104*0cad855fSPaul Burton ctx->offset + (i * 8), ctx->curr[i]); 105*0cad855fSPaul Burton if (err) 106*0cad855fSPaul Burton break; 107*0cad855fSPaul Burton } 108*0cad855fSPaul Burton 109*0cad855fSPaul Burton if (unlikely(err)) 110*0cad855fSPaul Burton pr_err_ratelimited("Failed to update LCD display: %d\n", err); 111*0cad855fSPaul Burton } 112*0cad855fSPaul Burton 113*0cad855fSPaul Burton static struct img_ascii_lcd_config malta_config = { 114*0cad855fSPaul Burton .num_chars = 8, 115*0cad855fSPaul Burton .external_regmap = true, 116*0cad855fSPaul Burton .update = malta_update, 117*0cad855fSPaul Burton }; 118*0cad855fSPaul Burton 119*0cad855fSPaul Burton /* 120*0cad855fSPaul Burton * MIPS SEAD3 development board 121*0cad855fSPaul Burton */ 122*0cad855fSPaul Burton 123*0cad855fSPaul Burton enum { 124*0cad855fSPaul Burton SEAD3_REG_LCD_CTRL = 0x00, 125*0cad855fSPaul Burton #define SEAD3_REG_LCD_CTRL_SETDRAM BIT(7) 126*0cad855fSPaul Burton SEAD3_REG_LCD_DATA = 0x08, 127*0cad855fSPaul Burton SEAD3_REG_CPLD_STATUS = 0x10, 128*0cad855fSPaul Burton #define SEAD3_REG_CPLD_STATUS_BUSY BIT(0) 129*0cad855fSPaul Burton SEAD3_REG_CPLD_DATA = 0x18, 130*0cad855fSPaul Burton #define SEAD3_REG_CPLD_DATA_BUSY BIT(7) 131*0cad855fSPaul Burton }; 132*0cad855fSPaul Burton 133*0cad855fSPaul Burton static int sead3_wait_sm_idle(struct img_ascii_lcd_ctx *ctx) 134*0cad855fSPaul Burton { 135*0cad855fSPaul Burton unsigned int status; 136*0cad855fSPaul Burton int err; 137*0cad855fSPaul Burton 138*0cad855fSPaul Burton do { 139*0cad855fSPaul Burton err = regmap_read(ctx->regmap, 140*0cad855fSPaul Burton ctx->offset + SEAD3_REG_CPLD_STATUS, 141*0cad855fSPaul Burton &status); 142*0cad855fSPaul Burton if (err) 143*0cad855fSPaul Burton return err; 144*0cad855fSPaul Burton } while (status & SEAD3_REG_CPLD_STATUS_BUSY); 145*0cad855fSPaul Burton 146*0cad855fSPaul Burton return 0; 147*0cad855fSPaul Burton 148*0cad855fSPaul Burton } 149*0cad855fSPaul Burton 150*0cad855fSPaul Burton static int sead3_wait_lcd_idle(struct img_ascii_lcd_ctx *ctx) 151*0cad855fSPaul Burton { 152*0cad855fSPaul Burton unsigned int cpld_data; 153*0cad855fSPaul Burton int err; 154*0cad855fSPaul Burton 155*0cad855fSPaul Burton err = sead3_wait_sm_idle(ctx); 156*0cad855fSPaul Burton if (err) 157*0cad855fSPaul Burton return err; 158*0cad855fSPaul Burton 159*0cad855fSPaul Burton do { 160*0cad855fSPaul Burton err = regmap_read(ctx->regmap, 161*0cad855fSPaul Burton ctx->offset + SEAD3_REG_LCD_CTRL, 162*0cad855fSPaul Burton &cpld_data); 163*0cad855fSPaul Burton if (err) 164*0cad855fSPaul Burton return err; 165*0cad855fSPaul Burton 166*0cad855fSPaul Burton err = sead3_wait_sm_idle(ctx); 167*0cad855fSPaul Burton if (err) 168*0cad855fSPaul Burton return err; 169*0cad855fSPaul Burton 170*0cad855fSPaul Burton err = regmap_read(ctx->regmap, 171*0cad855fSPaul Burton ctx->offset + SEAD3_REG_CPLD_DATA, 172*0cad855fSPaul Burton &cpld_data); 173*0cad855fSPaul Burton if (err) 174*0cad855fSPaul Burton return err; 175*0cad855fSPaul Burton } while (cpld_data & SEAD3_REG_CPLD_DATA_BUSY); 176*0cad855fSPaul Burton 177*0cad855fSPaul Burton return 0; 178*0cad855fSPaul Burton } 179*0cad855fSPaul Burton 180*0cad855fSPaul Burton static void sead3_update(struct img_ascii_lcd_ctx *ctx) 181*0cad855fSPaul Burton { 182*0cad855fSPaul Burton unsigned int i; 183*0cad855fSPaul Burton int err; 184*0cad855fSPaul Burton 185*0cad855fSPaul Burton for (i = 0; i < ctx->cfg->num_chars; i++) { 186*0cad855fSPaul Burton err = sead3_wait_lcd_idle(ctx); 187*0cad855fSPaul Burton if (err) 188*0cad855fSPaul Burton break; 189*0cad855fSPaul Burton 190*0cad855fSPaul Burton err = regmap_write(ctx->regmap, 191*0cad855fSPaul Burton ctx->offset + SEAD3_REG_LCD_CTRL, 192*0cad855fSPaul Burton SEAD3_REG_LCD_CTRL_SETDRAM | i); 193*0cad855fSPaul Burton if (err) 194*0cad855fSPaul Burton break; 195*0cad855fSPaul Burton 196*0cad855fSPaul Burton err = sead3_wait_lcd_idle(ctx); 197*0cad855fSPaul Burton if (err) 198*0cad855fSPaul Burton break; 199*0cad855fSPaul Burton 200*0cad855fSPaul Burton err = regmap_write(ctx->regmap, 201*0cad855fSPaul Burton ctx->offset + SEAD3_REG_LCD_DATA, 202*0cad855fSPaul Burton ctx->curr[i]); 203*0cad855fSPaul Burton if (err) 204*0cad855fSPaul Burton break; 205*0cad855fSPaul Burton } 206*0cad855fSPaul Burton 207*0cad855fSPaul Burton if (unlikely(err)) 208*0cad855fSPaul Burton pr_err_ratelimited("Failed to update LCD display: %d\n", err); 209*0cad855fSPaul Burton } 210*0cad855fSPaul Burton 211*0cad855fSPaul Burton static struct img_ascii_lcd_config sead3_config = { 212*0cad855fSPaul Burton .num_chars = 16, 213*0cad855fSPaul Burton .external_regmap = true, 214*0cad855fSPaul Burton .update = sead3_update, 215*0cad855fSPaul Burton }; 216*0cad855fSPaul Burton 217*0cad855fSPaul Burton static const struct of_device_id img_ascii_lcd_matches[] = { 218*0cad855fSPaul Burton { .compatible = "img,boston-lcd", .data = &boston_config }, 219*0cad855fSPaul Burton { .compatible = "mti,malta-lcd", .data = &malta_config }, 220*0cad855fSPaul Burton { .compatible = "mti,sead3-lcd", .data = &sead3_config }, 221*0cad855fSPaul Burton }; 222*0cad855fSPaul Burton 223*0cad855fSPaul Burton /** 224*0cad855fSPaul Burton * img_ascii_lcd_scroll() - scroll the display by a character 225*0cad855fSPaul Burton * @arg: really a pointer to the private data structure 226*0cad855fSPaul Burton * 227*0cad855fSPaul Burton * Scroll the current message along the LCD by one character, rearming the 228*0cad855fSPaul Burton * timer if required. 229*0cad855fSPaul Burton */ 230*0cad855fSPaul Burton static void img_ascii_lcd_scroll(unsigned long arg) 231*0cad855fSPaul Burton { 232*0cad855fSPaul Burton struct img_ascii_lcd_ctx *ctx = (struct img_ascii_lcd_ctx *)arg; 233*0cad855fSPaul Burton unsigned int i, ch = ctx->scroll_pos; 234*0cad855fSPaul Burton unsigned int num_chars = ctx->cfg->num_chars; 235*0cad855fSPaul Burton 236*0cad855fSPaul Burton /* update the current message string */ 237*0cad855fSPaul Burton for (i = 0; i < num_chars;) { 238*0cad855fSPaul Burton /* copy as many characters from the string as possible */ 239*0cad855fSPaul Burton for (; i < num_chars && ch < ctx->message_len; i++, ch++) 240*0cad855fSPaul Burton ctx->curr[i] = ctx->message[ch]; 241*0cad855fSPaul Burton 242*0cad855fSPaul Burton /* wrap around to the start of the string */ 243*0cad855fSPaul Burton ch = 0; 244*0cad855fSPaul Burton } 245*0cad855fSPaul Burton 246*0cad855fSPaul Burton /* update the LCD */ 247*0cad855fSPaul Burton ctx->cfg->update(ctx); 248*0cad855fSPaul Burton 249*0cad855fSPaul Burton /* move on to the next character */ 250*0cad855fSPaul Burton ctx->scroll_pos++; 251*0cad855fSPaul Burton ctx->scroll_pos %= ctx->message_len; 252*0cad855fSPaul Burton 253*0cad855fSPaul Burton /* rearm the timer */ 254*0cad855fSPaul Burton if (ctx->message_len > ctx->cfg->num_chars) 255*0cad855fSPaul Burton mod_timer(&ctx->timer, jiffies + ctx->scroll_rate); 256*0cad855fSPaul Burton } 257*0cad855fSPaul Burton 258*0cad855fSPaul Burton /** 259*0cad855fSPaul Burton * img_ascii_lcd_display() - set the message to be displayed 260*0cad855fSPaul Burton * @ctx: pointer to the private data structure 261*0cad855fSPaul Burton * @msg: the message to display 262*0cad855fSPaul Burton * @count: length of msg, or -1 263*0cad855fSPaul Burton * 264*0cad855fSPaul Burton * Display a new message @msg on the LCD. @msg can be longer than the number of 265*0cad855fSPaul Burton * characters the LCD can display, in which case it will begin scrolling across 266*0cad855fSPaul Burton * the LCD display. 267*0cad855fSPaul Burton * 268*0cad855fSPaul Burton * Return: 0 on success, -ENOMEM on memory allocation failure 269*0cad855fSPaul Burton */ 270*0cad855fSPaul Burton static int img_ascii_lcd_display(struct img_ascii_lcd_ctx *ctx, 271*0cad855fSPaul Burton const char *msg, ssize_t count) 272*0cad855fSPaul Burton { 273*0cad855fSPaul Burton char *new_msg; 274*0cad855fSPaul Burton 275*0cad855fSPaul Burton /* stop the scroll timer */ 276*0cad855fSPaul Burton del_timer_sync(&ctx->timer); 277*0cad855fSPaul Burton 278*0cad855fSPaul Burton if (count == -1) 279*0cad855fSPaul Burton count = strlen(msg); 280*0cad855fSPaul Burton 281*0cad855fSPaul Burton /* if the string ends with a newline, trim it */ 282*0cad855fSPaul Burton if (msg[count - 1] == '\n') 283*0cad855fSPaul Burton count--; 284*0cad855fSPaul Burton 285*0cad855fSPaul Burton new_msg = devm_kmalloc(&ctx->pdev->dev, count + 1, GFP_KERNEL); 286*0cad855fSPaul Burton if (!new_msg) 287*0cad855fSPaul Burton return -ENOMEM; 288*0cad855fSPaul Burton 289*0cad855fSPaul Burton memcpy(new_msg, msg, count); 290*0cad855fSPaul Burton new_msg[count] = 0; 291*0cad855fSPaul Burton 292*0cad855fSPaul Burton if (ctx->message) 293*0cad855fSPaul Burton devm_kfree(&ctx->pdev->dev, ctx->message); 294*0cad855fSPaul Burton 295*0cad855fSPaul Burton ctx->message = new_msg; 296*0cad855fSPaul Burton ctx->message_len = count; 297*0cad855fSPaul Burton ctx->scroll_pos = 0; 298*0cad855fSPaul Burton 299*0cad855fSPaul Burton /* update the LCD */ 300*0cad855fSPaul Burton img_ascii_lcd_scroll((unsigned long)ctx); 301*0cad855fSPaul Burton 302*0cad855fSPaul Burton return 0; 303*0cad855fSPaul Burton } 304*0cad855fSPaul Burton 305*0cad855fSPaul Burton /** 306*0cad855fSPaul Burton * message_show() - read message via sysfs 307*0cad855fSPaul Burton * @dev: the LCD device 308*0cad855fSPaul Burton * @attr: the LCD message attribute 309*0cad855fSPaul Burton * @buf: the buffer to read the message into 310*0cad855fSPaul Burton * 311*0cad855fSPaul Burton * Read the current message being displayed or scrolled across the LCD display 312*0cad855fSPaul Burton * into @buf, for reads from sysfs. 313*0cad855fSPaul Burton * 314*0cad855fSPaul Burton * Return: the number of characters written to @buf 315*0cad855fSPaul Burton */ 316*0cad855fSPaul Burton static ssize_t message_show(struct device *dev, struct device_attribute *attr, 317*0cad855fSPaul Burton char *buf) 318*0cad855fSPaul Burton { 319*0cad855fSPaul Burton struct img_ascii_lcd_ctx *ctx = dev_get_drvdata(dev); 320*0cad855fSPaul Burton 321*0cad855fSPaul Burton return sprintf(buf, "%s\n", ctx->message); 322*0cad855fSPaul Burton } 323*0cad855fSPaul Burton 324*0cad855fSPaul Burton /** 325*0cad855fSPaul Burton * message_store() - write a new message via sysfs 326*0cad855fSPaul Burton * @dev: the LCD device 327*0cad855fSPaul Burton * @attr: the LCD message attribute 328*0cad855fSPaul Burton * @buf: the buffer containing the new message 329*0cad855fSPaul Burton * @count: the size of the message in @buf 330*0cad855fSPaul Burton * 331*0cad855fSPaul Burton * Write a new message to display or scroll across the LCD display from sysfs. 332*0cad855fSPaul Burton * 333*0cad855fSPaul Burton * Return: the size of the message on success, else -ERRNO 334*0cad855fSPaul Burton */ 335*0cad855fSPaul Burton static ssize_t message_store(struct device *dev, struct device_attribute *attr, 336*0cad855fSPaul Burton const char *buf, size_t count) 337*0cad855fSPaul Burton { 338*0cad855fSPaul Burton struct img_ascii_lcd_ctx *ctx = dev_get_drvdata(dev); 339*0cad855fSPaul Burton int err; 340*0cad855fSPaul Burton 341*0cad855fSPaul Burton err = img_ascii_lcd_display(ctx, buf, count); 342*0cad855fSPaul Burton return err ?: count; 343*0cad855fSPaul Burton } 344*0cad855fSPaul Burton 345*0cad855fSPaul Burton static DEVICE_ATTR_RW(message); 346*0cad855fSPaul Burton 347*0cad855fSPaul Burton /** 348*0cad855fSPaul Burton * img_ascii_lcd_probe() - probe an LCD display device 349*0cad855fSPaul Burton * @pdev: the LCD platform device 350*0cad855fSPaul Burton * 351*0cad855fSPaul Burton * Probe an LCD display device, ensuring that we have the required resources in 352*0cad855fSPaul Burton * order to access the LCD & setting up private data as well as sysfs files. 353*0cad855fSPaul Burton * 354*0cad855fSPaul Burton * Return: 0 on success, else -ERRNO 355*0cad855fSPaul Burton */ 356*0cad855fSPaul Burton static int img_ascii_lcd_probe(struct platform_device *pdev) 357*0cad855fSPaul Burton { 358*0cad855fSPaul Burton const struct of_device_id *match; 359*0cad855fSPaul Burton const struct img_ascii_lcd_config *cfg; 360*0cad855fSPaul Burton struct img_ascii_lcd_ctx *ctx; 361*0cad855fSPaul Burton struct resource *res; 362*0cad855fSPaul Burton int err; 363*0cad855fSPaul Burton 364*0cad855fSPaul Burton match = of_match_device(img_ascii_lcd_matches, &pdev->dev); 365*0cad855fSPaul Burton if (!match) 366*0cad855fSPaul Burton return -ENODEV; 367*0cad855fSPaul Burton 368*0cad855fSPaul Burton cfg = match->data; 369*0cad855fSPaul Burton ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx) + cfg->num_chars, 370*0cad855fSPaul Burton GFP_KERNEL); 371*0cad855fSPaul Burton if (!ctx) 372*0cad855fSPaul Burton return -ENOMEM; 373*0cad855fSPaul Burton 374*0cad855fSPaul Burton if (cfg->external_regmap) { 375*0cad855fSPaul Burton ctx->regmap = syscon_node_to_regmap(pdev->dev.parent->of_node); 376*0cad855fSPaul Burton if (IS_ERR(ctx->regmap)) 377*0cad855fSPaul Burton return PTR_ERR(ctx->regmap); 378*0cad855fSPaul Burton 379*0cad855fSPaul Burton if (of_property_read_u32(pdev->dev.of_node, "offset", 380*0cad855fSPaul Burton &ctx->offset)) 381*0cad855fSPaul Burton return -EINVAL; 382*0cad855fSPaul Burton } else { 383*0cad855fSPaul Burton res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 384*0cad855fSPaul Burton ctx->base = devm_ioremap_resource(&pdev->dev, res); 385*0cad855fSPaul Burton if (IS_ERR(ctx->base)) 386*0cad855fSPaul Burton return PTR_ERR(ctx->base); 387*0cad855fSPaul Burton } 388*0cad855fSPaul Burton 389*0cad855fSPaul Burton ctx->pdev = pdev; 390*0cad855fSPaul Burton ctx->cfg = cfg; 391*0cad855fSPaul Burton ctx->message = NULL; 392*0cad855fSPaul Burton ctx->scroll_pos = 0; 393*0cad855fSPaul Burton ctx->scroll_rate = HZ / 2; 394*0cad855fSPaul Burton 395*0cad855fSPaul Burton /* initialise a timer for scrolling the message */ 396*0cad855fSPaul Burton init_timer(&ctx->timer); 397*0cad855fSPaul Burton ctx->timer.function = img_ascii_lcd_scroll; 398*0cad855fSPaul Burton ctx->timer.data = (unsigned long)ctx; 399*0cad855fSPaul Burton 400*0cad855fSPaul Burton platform_set_drvdata(pdev, ctx); 401*0cad855fSPaul Burton 402*0cad855fSPaul Burton /* display a default message */ 403*0cad855fSPaul Burton err = img_ascii_lcd_display(ctx, "Linux " UTS_RELEASE " ", -1); 404*0cad855fSPaul Burton if (err) 405*0cad855fSPaul Burton goto out_del_timer; 406*0cad855fSPaul Burton 407*0cad855fSPaul Burton err = device_create_file(&pdev->dev, &dev_attr_message); 408*0cad855fSPaul Burton if (err) 409*0cad855fSPaul Burton goto out_del_timer; 410*0cad855fSPaul Burton 411*0cad855fSPaul Burton return 0; 412*0cad855fSPaul Burton out_del_timer: 413*0cad855fSPaul Burton del_timer_sync(&ctx->timer); 414*0cad855fSPaul Burton return err; 415*0cad855fSPaul Burton } 416*0cad855fSPaul Burton 417*0cad855fSPaul Burton /** 418*0cad855fSPaul Burton * img_ascii_lcd_remove() - remove an LCD display device 419*0cad855fSPaul Burton * @pdev: the LCD platform device 420*0cad855fSPaul Burton * 421*0cad855fSPaul Burton * Remove an LCD display device, freeing private resources & ensuring that the 422*0cad855fSPaul Burton * driver stops using the LCD display registers. 423*0cad855fSPaul Burton * 424*0cad855fSPaul Burton * Return: 0 425*0cad855fSPaul Burton */ 426*0cad855fSPaul Burton static int img_ascii_lcd_remove(struct platform_device *pdev) 427*0cad855fSPaul Burton { 428*0cad855fSPaul Burton struct img_ascii_lcd_ctx *ctx = platform_get_drvdata(pdev); 429*0cad855fSPaul Burton 430*0cad855fSPaul Burton device_remove_file(&pdev->dev, &dev_attr_message); 431*0cad855fSPaul Burton del_timer_sync(&ctx->timer); 432*0cad855fSPaul Burton return 0; 433*0cad855fSPaul Burton } 434*0cad855fSPaul Burton 435*0cad855fSPaul Burton static struct platform_driver img_ascii_lcd_driver = { 436*0cad855fSPaul Burton .driver = { 437*0cad855fSPaul Burton .name = "img-ascii-lcd", 438*0cad855fSPaul Burton .of_match_table = img_ascii_lcd_matches, 439*0cad855fSPaul Burton }, 440*0cad855fSPaul Burton .probe = img_ascii_lcd_probe, 441*0cad855fSPaul Burton .remove = img_ascii_lcd_remove, 442*0cad855fSPaul Burton }; 443*0cad855fSPaul Burton module_platform_driver(img_ascii_lcd_driver); 444