607 lines · c
1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * LCD driver for MIPI DBI-C / DCS compatible LCDs4 *5 * Copyright (C) 2006 Nokia Corporation6 * Author: Imre Deak <imre.deak@nokia.com>7 */8#include <linux/device.h>9#include <linux/delay.h>10#include <linux/gpio/consumer.h>11#include <linux/slab.h>12#include <linux/workqueue.h>13#include <linux/spi/spi.h>14#include <linux/module.h>15 16#include <linux/platform_data/lcd-mipid.h>17 18#include "omapfb.h"19 20#define MIPID_MODULE_NAME "lcd_mipid"21 22#define MIPID_CMD_READ_DISP_ID 0x0423#define MIPID_CMD_READ_RED 0x0624#define MIPID_CMD_READ_GREEN 0x0725#define MIPID_CMD_READ_BLUE 0x0826#define MIPID_CMD_READ_DISP_STATUS 0x0927#define MIPID_CMD_RDDSDR 0x0F28#define MIPID_CMD_SLEEP_IN 0x1029#define MIPID_CMD_SLEEP_OUT 0x1130#define MIPID_CMD_DISP_OFF 0x2831#define MIPID_CMD_DISP_ON 0x2932 33#define MIPID_ESD_CHECK_PERIOD msecs_to_jiffies(5000)34 35#define to_mipid_device(p) container_of(p, struct mipid_device, \36 panel)37struct mipid_device {38 int enabled;39 int revision;40 unsigned int saved_bklight_level;41 unsigned long hw_guard_end; /* next value of jiffies42 when we can issue the43 next sleep in/out command */44 unsigned long hw_guard_wait; /* max guard time in jiffies */45 struct gpio_desc *reset;46 47 struct omapfb_device *fbdev;48 struct spi_device *spi;49 struct mutex mutex;50 struct lcd_panel panel;51 52 struct delayed_work esd_work;53 void (*esd_check)(struct mipid_device *m);54};55 56static void mipid_transfer(struct mipid_device *md, int cmd, const u8 *wbuf,57 int wlen, u8 *rbuf, int rlen)58{59 struct spi_message m;60 struct spi_transfer *x, xfer[4];61 u16 w;62 int r;63 64 BUG_ON(md->spi == NULL);65 66 spi_message_init(&m);67 68 memset(xfer, 0, sizeof(xfer));69 x = &xfer[0];70 71 cmd &= 0xff;72 x->tx_buf = &cmd;73 x->bits_per_word = 9;74 x->len = 2;75 spi_message_add_tail(x, &m);76 77 if (wlen) {78 x++;79 x->tx_buf = wbuf;80 x->len = wlen;81 x->bits_per_word = 9;82 spi_message_add_tail(x, &m);83 }84 85 if (rlen) {86 x++;87 x->rx_buf = &w;88 x->len = 1;89 spi_message_add_tail(x, &m);90 91 if (rlen > 1) {92 /* Arrange for the extra clock before the first93 * data bit.94 */95 x->bits_per_word = 9;96 x->len = 2;97 98 x++;99 x->rx_buf = &rbuf[1];100 x->len = rlen - 1;101 spi_message_add_tail(x, &m);102 }103 }104 105 r = spi_sync(md->spi, &m);106 if (r < 0)107 dev_dbg(&md->spi->dev, "spi_sync %d\n", r);108 109 if (rlen)110 rbuf[0] = w & 0xff;111}112 113static inline void mipid_cmd(struct mipid_device *md, int cmd)114{115 mipid_transfer(md, cmd, NULL, 0, NULL, 0);116}117 118static inline void mipid_write(struct mipid_device *md,119 int reg, const u8 *buf, int len)120{121 mipid_transfer(md, reg, buf, len, NULL, 0);122}123 124static inline void mipid_read(struct mipid_device *md,125 int reg, u8 *buf, int len)126{127 mipid_transfer(md, reg, NULL, 0, buf, len);128}129 130static void set_data_lines(struct mipid_device *md, int data_lines)131{132 u16 par;133 134 switch (data_lines) {135 case 16:136 par = 0x150;137 break;138 case 18:139 par = 0x160;140 break;141 case 24:142 par = 0x170;143 break;144 }145 mipid_write(md, 0x3a, (u8 *)&par, 2);146}147 148static void send_init_string(struct mipid_device *md)149{150 u16 initpar[] = { 0x0102, 0x0100, 0x0100 };151 152 mipid_write(md, 0xc2, (u8 *)initpar, sizeof(initpar));153 set_data_lines(md, md->panel.data_lines);154}155 156static void hw_guard_start(struct mipid_device *md, int guard_msec)157{158 md->hw_guard_wait = msecs_to_jiffies(guard_msec);159 md->hw_guard_end = jiffies + md->hw_guard_wait;160}161 162static void hw_guard_wait(struct mipid_device *md)163{164 unsigned long wait = md->hw_guard_end - jiffies;165 166 if ((long)wait > 0 && time_before_eq(wait, md->hw_guard_wait)) {167 set_current_state(TASK_UNINTERRUPTIBLE);168 schedule_timeout(wait);169 }170}171 172static void set_sleep_mode(struct mipid_device *md, int on)173{174 int cmd, sleep_time = 50;175 176 if (on)177 cmd = MIPID_CMD_SLEEP_IN;178 else179 cmd = MIPID_CMD_SLEEP_OUT;180 hw_guard_wait(md);181 mipid_cmd(md, cmd);182 hw_guard_start(md, 120);183 /*184 * When we enable the panel, it seems we _have_ to sleep185 * 120 ms before sending the init string. When disabling the186 * panel we'll sleep for the duration of 2 frames, so that the187 * controller can still provide the PCLK,HS,VS signals.188 */189 if (!on)190 sleep_time = 120;191 msleep(sleep_time);192}193 194static void set_display_state(struct mipid_device *md, int enabled)195{196 int cmd = enabled ? MIPID_CMD_DISP_ON : MIPID_CMD_DISP_OFF;197 198 mipid_cmd(md, cmd);199}200 201static int mipid_set_bklight_level(struct lcd_panel *panel, unsigned int level)202{203 struct mipid_device *md = to_mipid_device(panel);204 struct mipid_platform_data *pd = md->spi->dev.platform_data;205 206 if (pd->get_bklight_max == NULL || pd->set_bklight_level == NULL)207 return -ENODEV;208 if (level > pd->get_bklight_max(pd))209 return -EINVAL;210 if (!md->enabled) {211 md->saved_bklight_level = level;212 return 0;213 }214 pd->set_bklight_level(pd, level);215 216 return 0;217}218 219static unsigned int mipid_get_bklight_level(struct lcd_panel *panel)220{221 struct mipid_device *md = to_mipid_device(panel);222 struct mipid_platform_data *pd = md->spi->dev.platform_data;223 224 if (pd->get_bklight_level == NULL)225 return -ENODEV;226 return pd->get_bklight_level(pd);227}228 229static unsigned int mipid_get_bklight_max(struct lcd_panel *panel)230{231 struct mipid_device *md = to_mipid_device(panel);232 struct mipid_platform_data *pd = md->spi->dev.platform_data;233 234 if (pd->get_bklight_max == NULL)235 return -ENODEV;236 237 return pd->get_bklight_max(pd);238}239 240static unsigned long mipid_get_caps(struct lcd_panel *panel)241{242 return OMAPFB_CAPS_SET_BACKLIGHT;243}244 245static u16 read_first_pixel(struct mipid_device *md)246{247 u16 pixel;248 u8 red, green, blue;249 250 mutex_lock(&md->mutex);251 mipid_read(md, MIPID_CMD_READ_RED, &red, 1);252 mipid_read(md, MIPID_CMD_READ_GREEN, &green, 1);253 mipid_read(md, MIPID_CMD_READ_BLUE, &blue, 1);254 mutex_unlock(&md->mutex);255 256 switch (md->panel.data_lines) {257 case 16:258 pixel = ((red >> 1) << 11) | (green << 5) | (blue >> 1);259 break;260 case 24:261 /* 24 bit -> 16 bit */262 pixel = ((red >> 3) << 11) | ((green >> 2) << 5) |263 (blue >> 3);264 break;265 default:266 pixel = 0;267 BUG();268 }269 270 return pixel;271}272 273static int mipid_run_test(struct lcd_panel *panel, int test_num)274{275 struct mipid_device *md = to_mipid_device(panel);276 static const u16 test_values[4] = {277 0x0000, 0xffff, 0xaaaa, 0x5555,278 };279 int i;280 281 if (test_num != MIPID_TEST_RGB_LINES)282 return MIPID_TEST_INVALID;283 284 for (i = 0; i < ARRAY_SIZE(test_values); i++) {285 int delay;286 unsigned long tmo;287 288 omapfb_write_first_pixel(md->fbdev, test_values[i]);289 tmo = jiffies + msecs_to_jiffies(100);290 delay = 25;291 while (1) {292 u16 pixel;293 294 msleep(delay);295 pixel = read_first_pixel(md);296 if (pixel == test_values[i])297 break;298 if (time_after(jiffies, tmo)) {299 dev_err(&md->spi->dev,300 "MIPI LCD RGB I/F test failed: "301 "expecting %04x, got %04x\n",302 test_values[i], pixel);303 return MIPID_TEST_FAILED;304 }305 delay = 10;306 }307 }308 309 return 0;310}311 312static void ls041y3_esd_recover(struct mipid_device *md)313{314 dev_err(&md->spi->dev, "performing LCD ESD recovery\n");315 set_sleep_mode(md, 1);316 set_sleep_mode(md, 0);317}318 319static void ls041y3_esd_check_mode1(struct mipid_device *md)320{321 u8 state1, state2;322 323 mipid_read(md, MIPID_CMD_RDDSDR, &state1, 1);324 set_sleep_mode(md, 0);325 mipid_read(md, MIPID_CMD_RDDSDR, &state2, 1);326 dev_dbg(&md->spi->dev, "ESD mode 1 state1 %02x state2 %02x\n",327 state1, state2);328 /* Each sleep out command will trigger a self diagnostic and flip329 * Bit6 if the test passes.330 */331 if (!((state1 ^ state2) & (1 << 6)))332 ls041y3_esd_recover(md);333}334 335static void ls041y3_esd_check_mode2(struct mipid_device *md)336{337 int i;338 u8 rbuf[2];339 static const struct {340 int cmd;341 int wlen;342 u16 wbuf[3];343 } *rd, rd_ctrl[7] = {344 { 0xb0, 4, { 0x0101, 0x01fe, } },345 { 0xb1, 4, { 0x01de, 0x0121, } },346 { 0xc2, 4, { 0x0100, 0x0100, } },347 { 0xbd, 2, { 0x0100, } },348 { 0xc2, 4, { 0x01fc, 0x0103, } },349 { 0xb4, 0, },350 { 0x00, 0, },351 };352 353 rd = rd_ctrl;354 for (i = 0; i < 3; i++, rd++)355 mipid_write(md, rd->cmd, (u8 *)rd->wbuf, rd->wlen);356 357 udelay(10);358 mipid_read(md, rd->cmd, rbuf, 2);359 rd++;360 361 for (i = 0; i < 3; i++, rd++) {362 udelay(10);363 mipid_write(md, rd->cmd, (u8 *)rd->wbuf, rd->wlen);364 }365 366 dev_dbg(&md->spi->dev, "ESD mode 2 state %02x\n", rbuf[1]);367 if (rbuf[1] == 0x00)368 ls041y3_esd_recover(md);369}370 371static void ls041y3_esd_check(struct mipid_device *md)372{373 ls041y3_esd_check_mode1(md);374 if (md->revision >= 0x88)375 ls041y3_esd_check_mode2(md);376}377 378static void mipid_esd_start_check(struct mipid_device *md)379{380 if (md->esd_check != NULL)381 schedule_delayed_work(&md->esd_work,382 MIPID_ESD_CHECK_PERIOD);383}384 385static void mipid_esd_stop_check(struct mipid_device *md)386{387 if (md->esd_check != NULL)388 cancel_delayed_work_sync(&md->esd_work);389}390 391static void mipid_esd_work(struct work_struct *work)392{393 struct mipid_device *md = container_of(work, struct mipid_device,394 esd_work.work);395 396 mutex_lock(&md->mutex);397 md->esd_check(md);398 mutex_unlock(&md->mutex);399 mipid_esd_start_check(md);400}401 402static int mipid_enable(struct lcd_panel *panel)403{404 struct mipid_device *md = to_mipid_device(panel);405 406 mutex_lock(&md->mutex);407 408 if (md->enabled) {409 mutex_unlock(&md->mutex);410 return 0;411 }412 set_sleep_mode(md, 0);413 md->enabled = 1;414 send_init_string(md);415 set_display_state(md, 1);416 mipid_set_bklight_level(panel, md->saved_bklight_level);417 mipid_esd_start_check(md);418 419 mutex_unlock(&md->mutex);420 return 0;421}422 423static void mipid_disable(struct lcd_panel *panel)424{425 struct mipid_device *md = to_mipid_device(panel);426 427 /*428 * A final ESD work might be called before returning,429 * so do this without holding the lock.430 */431 mipid_esd_stop_check(md);432 mutex_lock(&md->mutex);433 434 if (!md->enabled) {435 mutex_unlock(&md->mutex);436 return;437 }438 md->saved_bklight_level = mipid_get_bklight_level(panel);439 mipid_set_bklight_level(panel, 0);440 set_display_state(md, 0);441 set_sleep_mode(md, 1);442 md->enabled = 0;443 444 mutex_unlock(&md->mutex);445}446 447static int panel_enabled(struct mipid_device *md)448{449 u32 disp_status;450 int enabled;451 452 mipid_read(md, MIPID_CMD_READ_DISP_STATUS, (u8 *)&disp_status, 4);453 disp_status = __be32_to_cpu(disp_status);454 enabled = (disp_status & (1 << 17)) && (disp_status & (1 << 10));455 dev_dbg(&md->spi->dev,456 "LCD panel %senabled by bootloader (status 0x%04x)\n",457 enabled ? "" : "not ", disp_status);458 return enabled;459}460 461static int mipid_init(struct lcd_panel *panel,462 struct omapfb_device *fbdev)463{464 struct mipid_device *md = to_mipid_device(panel);465 466 md->fbdev = fbdev;467 INIT_DELAYED_WORK(&md->esd_work, mipid_esd_work);468 mutex_init(&md->mutex);469 470 md->enabled = panel_enabled(md);471 472 if (md->enabled)473 mipid_esd_start_check(md);474 else475 md->saved_bklight_level = mipid_get_bklight_level(panel);476 477 return 0;478}479 480static void mipid_cleanup(struct lcd_panel *panel)481{482 struct mipid_device *md = to_mipid_device(panel);483 484 if (md->enabled)485 mipid_esd_stop_check(md);486}487 488static const struct lcd_panel mipid_panel = {489 .config = OMAP_LCDC_PANEL_TFT,490 491 .bpp = 16,492 .x_res = 800,493 .y_res = 480,494 .pixel_clock = 21940,495 .hsw = 50,496 .hfp = 20,497 .hbp = 15,498 .vsw = 2,499 .vfp = 1,500 .vbp = 3,501 502 .init = mipid_init,503 .cleanup = mipid_cleanup,504 .enable = mipid_enable,505 .disable = mipid_disable,506 .get_caps = mipid_get_caps,507 .set_bklight_level = mipid_set_bklight_level,508 .get_bklight_level = mipid_get_bklight_level,509 .get_bklight_max = mipid_get_bklight_max,510 .run_test = mipid_run_test,511};512 513static int mipid_detect(struct mipid_device *md)514{515 struct mipid_platform_data *pdata;516 u8 display_id[3];517 518 pdata = md->spi->dev.platform_data;519 if (pdata == NULL) {520 dev_err(&md->spi->dev, "missing platform data\n");521 return -ENOENT;522 }523 524 mipid_read(md, MIPID_CMD_READ_DISP_ID, display_id, 3);525 dev_dbg(&md->spi->dev, "MIPI display ID: %02x%02x%02x\n",526 display_id[0], display_id[1], display_id[2]);527 528 switch (display_id[0]) {529 case 0x45:530 md->panel.name = "lph8923";531 break;532 case 0x83:533 md->panel.name = "ls041y3";534 md->esd_check = ls041y3_esd_check;535 break;536 default:537 md->panel.name = "unknown";538 dev_err(&md->spi->dev, "invalid display ID\n");539 return -ENODEV;540 }541 542 md->revision = display_id[1];543 md->panel.data_lines = pdata->data_lines;544 pr_info("omapfb: %s rev %02x LCD detected, %d data lines\n",545 md->panel.name, md->revision, md->panel.data_lines);546 547 return 0;548}549 550static int mipid_spi_probe(struct spi_device *spi)551{552 struct mipid_device *md;553 int r;554 555 md = kzalloc(sizeof(*md), GFP_KERNEL);556 if (md == NULL) {557 dev_err(&spi->dev, "out of memory\n");558 return -ENOMEM;559 }560 561 /* This will de-assert RESET if active */562 md->reset = gpiod_get(&spi->dev, "reset", GPIOD_OUT_LOW);563 if (IS_ERR(md->reset))564 return dev_err_probe(&spi->dev, PTR_ERR(md->reset),565 "no reset GPIO line\n");566 567 spi->mode = SPI_MODE_0;568 md->spi = spi;569 dev_set_drvdata(&spi->dev, md);570 md->panel = mipid_panel;571 572 r = mipid_detect(md);573 if (r < 0)574 goto free_md;575 576 omapfb_register_panel(&md->panel);577 578 return 0;579 580free_md:581 kfree(md);582 return r;583}584 585static void mipid_spi_remove(struct spi_device *spi)586{587 struct mipid_device *md = dev_get_drvdata(&spi->dev);588 589 /* Asserts RESET */590 gpiod_set_value(md->reset, 1);591 mipid_disable(&md->panel);592 kfree(md);593}594 595static struct spi_driver mipid_spi_driver = {596 .driver = {597 .name = MIPID_MODULE_NAME,598 },599 .probe = mipid_spi_probe,600 .remove = mipid_spi_remove,601};602 603module_spi_driver(mipid_spi_driver);604 605MODULE_DESCRIPTION("MIPI display driver");606MODULE_LICENSE("GPL");607