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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * DRM driver for Pervasive Displays RePaper branded e-ink panels4 *5 * Copyright 2013-2017 Pervasive Displays, Inc.6 * Copyright 2017 Noralf Trønnes7 *8 * The driver supports:9 * Material Film: Aurora Mb (V231)10 * Driver IC: G2 (eTC)11 *12 * The controller code was taken from the userspace driver:13 * https://github.com/repaper/gratis14 */15 16#include <linux/delay.h>17#include <linux/gpio/consumer.h>18#include <linux/module.h>19#include <linux/property.h>20#include <linux/sched/clock.h>21#include <linux/spi/spi.h>22#include <linux/thermal.h>23 24#include <drm/drm_atomic_helper.h>25#include <drm/drm_connector.h>26#include <drm/drm_damage_helper.h>27#include <drm/drm_drv.h>28#include <drm/drm_fb_dma_helper.h>29#include <drm/drm_fbdev_dma.h>30#include <drm/drm_format_helper.h>31#include <drm/drm_framebuffer.h>32#include <drm/drm_gem_atomic_helper.h>33#include <drm/drm_gem_dma_helper.h>34#include <drm/drm_gem_framebuffer_helper.h>35#include <drm/drm_managed.h>36#include <drm/drm_modes.h>37#include <drm/drm_rect.h>38#include <drm/drm_probe_helper.h>39#include <drm/drm_simple_kms_helper.h>40 41#define REPAPER_RID_G2_COG_ID 0x1242 43enum repaper_model {44 /* 0 is reserved to avoid clashing with NULL */45 E1144CS021 = 1,46 E1190CS021,47 E2200CS021,48 E2271CS021,49};50 51enum repaper_stage { /* Image pixel -> Display pixel */52 REPAPER_COMPENSATE, /* B -> W, W -> B (Current Image) */53 REPAPER_WHITE, /* B -> N, W -> W (Current Image) */54 REPAPER_INVERSE, /* B -> N, W -> B (New Image) */55 REPAPER_NORMAL /* B -> B, W -> W (New Image) */56};57 58enum repaper_epd_border_byte {59 REPAPER_BORDER_BYTE_NONE,60 REPAPER_BORDER_BYTE_ZERO,61 REPAPER_BORDER_BYTE_SET,62};63 64struct repaper_epd {65 struct drm_device drm;66 struct drm_simple_display_pipe pipe;67 const struct drm_display_mode *mode;68 struct drm_connector connector;69 struct spi_device *spi;70 71 struct gpio_desc *panel_on;72 struct gpio_desc *border;73 struct gpio_desc *discharge;74 struct gpio_desc *reset;75 struct gpio_desc *busy;76 77 struct thermal_zone_device *thermal;78 79 unsigned int height;80 unsigned int width;81 unsigned int bytes_per_scan;82 const u8 *channel_select;83 unsigned int stage_time;84 unsigned int factored_stage_time;85 bool middle_scan;86 bool pre_border_byte;87 enum repaper_epd_border_byte border_byte;88 89 u8 *line_buffer;90 void *current_frame;91 92 bool cleared;93 bool partial;94};95 96static inline struct repaper_epd *drm_to_epd(struct drm_device *drm)97{98 return container_of(drm, struct repaper_epd, drm);99}100 101static int repaper_spi_transfer(struct spi_device *spi, u8 header,102 const void *tx, void *rx, size_t len)103{104 void *txbuf = NULL, *rxbuf = NULL;105 struct spi_transfer tr[2] = {};106 u8 *headerbuf;107 int ret;108 109 headerbuf = kmalloc(1, GFP_KERNEL);110 if (!headerbuf)111 return -ENOMEM;112 113 headerbuf[0] = header;114 tr[0].tx_buf = headerbuf;115 tr[0].len = 1;116 117 /* Stack allocated tx? */118 if (tx && len <= 32) {119 txbuf = kmemdup(tx, len, GFP_KERNEL);120 if (!txbuf) {121 ret = -ENOMEM;122 goto out_free;123 }124 }125 126 if (rx) {127 rxbuf = kmalloc(len, GFP_KERNEL);128 if (!rxbuf) {129 ret = -ENOMEM;130 goto out_free;131 }132 }133 134 tr[1].tx_buf = txbuf ? txbuf : tx;135 tr[1].rx_buf = rxbuf;136 tr[1].len = len;137 138 ndelay(80);139 ret = spi_sync_transfer(spi, tr, 2);140 if (rx && !ret)141 memcpy(rx, rxbuf, len);142 143out_free:144 kfree(headerbuf);145 kfree(txbuf);146 kfree(rxbuf);147 148 return ret;149}150 151static int repaper_write_buf(struct spi_device *spi, u8 reg,152 const u8 *buf, size_t len)153{154 int ret;155 156 ret = repaper_spi_transfer(spi, 0x70, ®, NULL, 1);157 if (ret)158 return ret;159 160 return repaper_spi_transfer(spi, 0x72, buf, NULL, len);161}162 163static int repaper_write_val(struct spi_device *spi, u8 reg, u8 val)164{165 return repaper_write_buf(spi, reg, &val, 1);166}167 168static int repaper_read_val(struct spi_device *spi, u8 reg)169{170 int ret;171 u8 val;172 173 ret = repaper_spi_transfer(spi, 0x70, ®, NULL, 1);174 if (ret)175 return ret;176 177 ret = repaper_spi_transfer(spi, 0x73, NULL, &val, 1);178 179 return ret ? ret : val;180}181 182static int repaper_read_id(struct spi_device *spi)183{184 int ret;185 u8 id;186 187 ret = repaper_spi_transfer(spi, 0x71, NULL, &id, 1);188 189 return ret ? ret : id;190}191 192static void repaper_spi_mosi_low(struct spi_device *spi)193{194 const u8 buf[1] = { 0 };195 196 spi_write(spi, buf, 1);197}198 199/* pixels on display are numbered from 1 so even is actually bits 1,3,5,... */200static void repaper_even_pixels(struct repaper_epd *epd, u8 **pp,201 const u8 *data, u8 fixed_value, const u8 *mask,202 enum repaper_stage stage)203{204 unsigned int b;205 206 for (b = 0; b < (epd->width / 8); b++) {207 if (data) {208 u8 pixels = data[b] & 0xaa;209 u8 pixel_mask = 0xff;210 u8 p1, p2, p3, p4;211 212 if (mask) {213 pixel_mask = (mask[b] ^ pixels) & 0xaa;214 pixel_mask |= pixel_mask >> 1;215 }216 217 switch (stage) {218 case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */219 pixels = 0xaa | ((pixels ^ 0xaa) >> 1);220 break;221 case REPAPER_WHITE: /* B -> N, W -> W (Current) */222 pixels = 0x55 + ((pixels ^ 0xaa) >> 1);223 break;224 case REPAPER_INVERSE: /* B -> N, W -> B (New) */225 pixels = 0x55 | (pixels ^ 0xaa);226 break;227 case REPAPER_NORMAL: /* B -> B, W -> W (New) */228 pixels = 0xaa | (pixels >> 1);229 break;230 }231 232 pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55);233 p1 = (pixels >> 6) & 0x03;234 p2 = (pixels >> 4) & 0x03;235 p3 = (pixels >> 2) & 0x03;236 p4 = (pixels >> 0) & 0x03;237 pixels = (p1 << 0) | (p2 << 2) | (p3 << 4) | (p4 << 6);238 *(*pp)++ = pixels;239 } else {240 *(*pp)++ = fixed_value;241 }242 }243}244 245/* pixels on display are numbered from 1 so odd is actually bits 0,2,4,... */246static void repaper_odd_pixels(struct repaper_epd *epd, u8 **pp,247 const u8 *data, u8 fixed_value, const u8 *mask,248 enum repaper_stage stage)249{250 unsigned int b;251 252 for (b = epd->width / 8; b > 0; b--) {253 if (data) {254 u8 pixels = data[b - 1] & 0x55;255 u8 pixel_mask = 0xff;256 257 if (mask) {258 pixel_mask = (mask[b - 1] ^ pixels) & 0x55;259 pixel_mask |= pixel_mask << 1;260 }261 262 switch (stage) {263 case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */264 pixels = 0xaa | (pixels ^ 0x55);265 break;266 case REPAPER_WHITE: /* B -> N, W -> W (Current) */267 pixels = 0x55 + (pixels ^ 0x55);268 break;269 case REPAPER_INVERSE: /* B -> N, W -> B (New) */270 pixels = 0x55 | ((pixels ^ 0x55) << 1);271 break;272 case REPAPER_NORMAL: /* B -> B, W -> W (New) */273 pixels = 0xaa | pixels;274 break;275 }276 277 pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55);278 *(*pp)++ = pixels;279 } else {280 *(*pp)++ = fixed_value;281 }282 }283}284 285/* interleave bits: (byte)76543210 -> (16 bit).7.6.5.4.3.2.1 */286static inline u16 repaper_interleave_bits(u16 value)287{288 value = (value | (value << 4)) & 0x0f0f;289 value = (value | (value << 2)) & 0x3333;290 value = (value | (value << 1)) & 0x5555;291 292 return value;293}294 295/* pixels on display are numbered from 1 */296static void repaper_all_pixels(struct repaper_epd *epd, u8 **pp,297 const u8 *data, u8 fixed_value, const u8 *mask,298 enum repaper_stage stage)299{300 unsigned int b;301 302 for (b = epd->width / 8; b > 0; b--) {303 if (data) {304 u16 pixels = repaper_interleave_bits(data[b - 1]);305 u16 pixel_mask = 0xffff;306 307 if (mask) {308 pixel_mask = repaper_interleave_bits(mask[b - 1]);309 310 pixel_mask = (pixel_mask ^ pixels) & 0x5555;311 pixel_mask |= pixel_mask << 1;312 }313 314 switch (stage) {315 case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */316 pixels = 0xaaaa | (pixels ^ 0x5555);317 break;318 case REPAPER_WHITE: /* B -> N, W -> W (Current) */319 pixels = 0x5555 + (pixels ^ 0x5555);320 break;321 case REPAPER_INVERSE: /* B -> N, W -> B (New) */322 pixels = 0x5555 | ((pixels ^ 0x5555) << 1);323 break;324 case REPAPER_NORMAL: /* B -> B, W -> W (New) */325 pixels = 0xaaaa | pixels;326 break;327 }328 329 pixels = (pixels & pixel_mask) | (~pixel_mask & 0x5555);330 *(*pp)++ = pixels >> 8;331 *(*pp)++ = pixels;332 } else {333 *(*pp)++ = fixed_value;334 *(*pp)++ = fixed_value;335 }336 }337}338 339/* output one line of scan and data bytes to the display */340static void repaper_one_line(struct repaper_epd *epd, unsigned int line,341 const u8 *data, u8 fixed_value, const u8 *mask,342 enum repaper_stage stage)343{344 u8 *p = epd->line_buffer;345 unsigned int b;346 347 repaper_spi_mosi_low(epd->spi);348 349 if (epd->pre_border_byte)350 *p++ = 0x00;351 352 if (epd->middle_scan) {353 /* data bytes */354 repaper_odd_pixels(epd, &p, data, fixed_value, mask, stage);355 356 /* scan line */357 for (b = epd->bytes_per_scan; b > 0; b--) {358 if (line / 4 == b - 1)359 *p++ = 0x03 << (2 * (line & 0x03));360 else361 *p++ = 0x00;362 }363 364 /* data bytes */365 repaper_even_pixels(epd, &p, data, fixed_value, mask, stage);366 } else {367 /*368 * even scan line, but as lines on display are numbered from 1,369 * line: 1,3,5,...370 */371 for (b = 0; b < epd->bytes_per_scan; b++) {372 if (0 != (line & 0x01) && line / 8 == b)373 *p++ = 0xc0 >> (line & 0x06);374 else375 *p++ = 0x00;376 }377 378 /* data bytes */379 repaper_all_pixels(epd, &p, data, fixed_value, mask, stage);380 381 /*382 * odd scan line, but as lines on display are numbered from 1,383 * line: 0,2,4,6,...384 */385 for (b = epd->bytes_per_scan; b > 0; b--) {386 if (0 == (line & 0x01) && line / 8 == b - 1)387 *p++ = 0x03 << (line & 0x06);388 else389 *p++ = 0x00;390 }391 }392 393 switch (epd->border_byte) {394 case REPAPER_BORDER_BYTE_NONE:395 break;396 397 case REPAPER_BORDER_BYTE_ZERO:398 *p++ = 0x00;399 break;400 401 case REPAPER_BORDER_BYTE_SET:402 switch (stage) {403 case REPAPER_COMPENSATE:404 case REPAPER_WHITE:405 case REPAPER_INVERSE:406 *p++ = 0x00;407 break;408 case REPAPER_NORMAL:409 *p++ = 0xaa;410 break;411 }412 break;413 }414 415 repaper_write_buf(epd->spi, 0x0a, epd->line_buffer,416 p - epd->line_buffer);417 418 /* Output data to panel */419 repaper_write_val(epd->spi, 0x02, 0x07);420 421 repaper_spi_mosi_low(epd->spi);422}423 424static void repaper_frame_fixed(struct repaper_epd *epd, u8 fixed_value,425 enum repaper_stage stage)426{427 unsigned int line;428 429 for (line = 0; line < epd->height; line++)430 repaper_one_line(epd, line, NULL, fixed_value, NULL, stage);431}432 433static void repaper_frame_data(struct repaper_epd *epd, const u8 *image,434 const u8 *mask, enum repaper_stage stage)435{436 unsigned int line;437 438 if (!mask) {439 for (line = 0; line < epd->height; line++) {440 repaper_one_line(epd, line,441 &image[line * (epd->width / 8)],442 0, NULL, stage);443 }444 } else {445 for (line = 0; line < epd->height; line++) {446 size_t n = line * epd->width / 8;447 448 repaper_one_line(epd, line, &image[n], 0, &mask[n],449 stage);450 }451 }452}453 454static void repaper_frame_fixed_repeat(struct repaper_epd *epd, u8 fixed_value,455 enum repaper_stage stage)456{457 u64 start = local_clock();458 u64 end = start + (epd->factored_stage_time * 1000 * 1000);459 460 do {461 repaper_frame_fixed(epd, fixed_value, stage);462 } while (local_clock() < end);463}464 465static void repaper_frame_data_repeat(struct repaper_epd *epd, const u8 *image,466 const u8 *mask, enum repaper_stage stage)467{468 u64 start = local_clock();469 u64 end = start + (epd->factored_stage_time * 1000 * 1000);470 471 do {472 repaper_frame_data(epd, image, mask, stage);473 } while (local_clock() < end);474}475 476static void repaper_get_temperature(struct repaper_epd *epd)477{478 int ret, temperature = 0;479 unsigned int factor10x;480 481 if (!epd->thermal)482 return;483 484 ret = thermal_zone_get_temp(epd->thermal, &temperature);485 if (ret) {486 DRM_DEV_ERROR(&epd->spi->dev, "Failed to get temperature (%d)\n", ret);487 return;488 }489 490 temperature /= 1000;491 492 if (temperature <= -10)493 factor10x = 170;494 else if (temperature <= -5)495 factor10x = 120;496 else if (temperature <= 5)497 factor10x = 80;498 else if (temperature <= 10)499 factor10x = 40;500 else if (temperature <= 15)501 factor10x = 30;502 else if (temperature <= 20)503 factor10x = 20;504 else if (temperature <= 40)505 factor10x = 10;506 else507 factor10x = 7;508 509 epd->factored_stage_time = epd->stage_time * factor10x / 10;510}511 512static int repaper_fb_dirty(struct drm_framebuffer *fb,513 struct drm_format_conv_state *fmtcnv_state)514{515 struct drm_gem_dma_object *dma_obj = drm_fb_dma_get_gem_obj(fb, 0);516 struct repaper_epd *epd = drm_to_epd(fb->dev);517 unsigned int dst_pitch = 0;518 struct iosys_map dst, vmap;519 struct drm_rect clip;520 int idx, ret = 0;521 u8 *buf = NULL;522 523 if (!drm_dev_enter(fb->dev, &idx))524 return -ENODEV;525 526 /* repaper can't do partial updates */527 clip.x1 = 0;528 clip.x2 = fb->width;529 clip.y1 = 0;530 clip.y2 = fb->height;531 532 repaper_get_temperature(epd);533 534 DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id,535 epd->factored_stage_time);536 537 buf = kmalloc(fb->width * fb->height / 8, GFP_KERNEL);538 if (!buf) {539 ret = -ENOMEM;540 goto out_exit;541 }542 543 ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE);544 if (ret)545 goto out_free;546 547 iosys_map_set_vaddr(&dst, buf);548 iosys_map_set_vaddr(&vmap, dma_obj->vaddr);549 drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, &vmap, fb, &clip, fmtcnv_state);550 551 drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE);552 553 if (epd->partial) {554 repaper_frame_data_repeat(epd, buf, epd->current_frame,555 REPAPER_NORMAL);556 } else if (epd->cleared) {557 repaper_frame_data_repeat(epd, epd->current_frame, NULL,558 REPAPER_COMPENSATE);559 repaper_frame_data_repeat(epd, epd->current_frame, NULL,560 REPAPER_WHITE);561 repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE);562 repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL);563 564 epd->partial = true;565 } else {566 /* Clear display (anything -> white) */567 repaper_frame_fixed_repeat(epd, 0xff, REPAPER_COMPENSATE);568 repaper_frame_fixed_repeat(epd, 0xff, REPAPER_WHITE);569 repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_INVERSE);570 repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_NORMAL);571 572 /* Assuming a clear (white) screen output an image */573 repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_COMPENSATE);574 repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_WHITE);575 repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE);576 repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL);577 578 epd->cleared = true;579 epd->partial = true;580 }581 582 memcpy(epd->current_frame, buf, fb->width * fb->height / 8);583 584 /*585 * An extra frame write is needed if pixels are set in the bottom line,586 * or else grey lines rises up from the pixels587 */588 if (epd->pre_border_byte) {589 unsigned int x;590 591 for (x = 0; x < (fb->width / 8); x++)592 if (buf[x + (fb->width * (fb->height - 1) / 8)]) {593 repaper_frame_data_repeat(epd, buf,594 epd->current_frame,595 REPAPER_NORMAL);596 break;597 }598 }599 600out_free:601 kfree(buf);602out_exit:603 drm_dev_exit(idx);604 605 return ret;606}607 608static void power_off(struct repaper_epd *epd)609{610 /* Turn off power and all signals */611 gpiod_set_value_cansleep(epd->reset, 0);612 gpiod_set_value_cansleep(epd->panel_on, 0);613 if (epd->border)614 gpiod_set_value_cansleep(epd->border, 0);615 616 /* Ensure SPI MOSI and CLOCK are Low before CS Low */617 repaper_spi_mosi_low(epd->spi);618 619 /* Discharge pulse */620 gpiod_set_value_cansleep(epd->discharge, 1);621 msleep(150);622 gpiod_set_value_cansleep(epd->discharge, 0);623}624 625static enum drm_mode_status repaper_pipe_mode_valid(struct drm_simple_display_pipe *pipe,626 const struct drm_display_mode *mode)627{628 struct drm_crtc *crtc = &pipe->crtc;629 struct repaper_epd *epd = drm_to_epd(crtc->dev);630 631 return drm_crtc_helper_mode_valid_fixed(crtc, mode, epd->mode);632}633 634static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe,635 struct drm_crtc_state *crtc_state,636 struct drm_plane_state *plane_state)637{638 struct repaper_epd *epd = drm_to_epd(pipe->crtc.dev);639 struct spi_device *spi = epd->spi;640 struct device *dev = &spi->dev;641 bool dc_ok = false;642 int i, ret, idx;643 644 if (!drm_dev_enter(pipe->crtc.dev, &idx))645 return;646 647 DRM_DEBUG_DRIVER("\n");648 649 /* Power up sequence */650 gpiod_set_value_cansleep(epd->reset, 0);651 gpiod_set_value_cansleep(epd->panel_on, 0);652 gpiod_set_value_cansleep(epd->discharge, 0);653 if (epd->border)654 gpiod_set_value_cansleep(epd->border, 0);655 repaper_spi_mosi_low(spi);656 usleep_range(5000, 10000);657 658 gpiod_set_value_cansleep(epd->panel_on, 1);659 /*660 * This delay comes from the repaper.org userspace driver, it's not661 * mentioned in the datasheet.662 */663 usleep_range(10000, 15000);664 gpiod_set_value_cansleep(epd->reset, 1);665 if (epd->border)666 gpiod_set_value_cansleep(epd->border, 1);667 usleep_range(5000, 10000);668 gpiod_set_value_cansleep(epd->reset, 0);669 usleep_range(5000, 10000);670 gpiod_set_value_cansleep(epd->reset, 1);671 usleep_range(5000, 10000);672 673 /* Wait for COG to become ready */674 for (i = 100; i > 0; i--) {675 if (!gpiod_get_value_cansleep(epd->busy))676 break;677 678 usleep_range(10, 100);679 }680 681 if (!i) {682 DRM_DEV_ERROR(dev, "timeout waiting for panel to become ready.\n");683 power_off(epd);684 goto out_exit;685 }686 687 repaper_read_id(spi);688 ret = repaper_read_id(spi);689 if (ret != REPAPER_RID_G2_COG_ID) {690 if (ret < 0)691 dev_err(dev, "failed to read chip (%d)\n", ret);692 else693 dev_err(dev, "wrong COG ID 0x%02x\n", ret);694 power_off(epd);695 goto out_exit;696 }697 698 /* Disable OE */699 repaper_write_val(spi, 0x02, 0x40);700 701 ret = repaper_read_val(spi, 0x0f);702 if (ret < 0 || !(ret & 0x80)) {703 if (ret < 0)704 DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret);705 else706 DRM_DEV_ERROR(dev, "panel is reported broken\n");707 power_off(epd);708 goto out_exit;709 }710 711 /* Power saving mode */712 repaper_write_val(spi, 0x0b, 0x02);713 /* Channel select */714 repaper_write_buf(spi, 0x01, epd->channel_select, 8);715 /* High power mode osc */716 repaper_write_val(spi, 0x07, 0xd1);717 /* Power setting */718 repaper_write_val(spi, 0x08, 0x02);719 /* Vcom level */720 repaper_write_val(spi, 0x09, 0xc2);721 /* Power setting */722 repaper_write_val(spi, 0x04, 0x03);723 /* Driver latch on */724 repaper_write_val(spi, 0x03, 0x01);725 /* Driver latch off */726 repaper_write_val(spi, 0x03, 0x00);727 usleep_range(5000, 10000);728 729 /* Start chargepump */730 for (i = 0; i < 4; ++i) {731 /* Charge pump positive voltage on - VGH/VDL on */732 repaper_write_val(spi, 0x05, 0x01);733 msleep(240);734 735 /* Charge pump negative voltage on - VGL/VDL on */736 repaper_write_val(spi, 0x05, 0x03);737 msleep(40);738 739 /* Charge pump Vcom on - Vcom driver on */740 repaper_write_val(spi, 0x05, 0x0f);741 msleep(40);742 743 /* check DC/DC */744 ret = repaper_read_val(spi, 0x0f);745 if (ret < 0) {746 DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret);747 power_off(epd);748 goto out_exit;749 }750 751 if (ret & 0x40) {752 dc_ok = true;753 break;754 }755 }756 757 if (!dc_ok) {758 DRM_DEV_ERROR(dev, "dc/dc failed\n");759 power_off(epd);760 goto out_exit;761 }762 763 /*764 * Output enable to disable765 * The userspace driver sets this to 0x04, but the datasheet says 0x06766 */767 repaper_write_val(spi, 0x02, 0x04);768 769 epd->partial = false;770out_exit:771 drm_dev_exit(idx);772}773 774static void repaper_pipe_disable(struct drm_simple_display_pipe *pipe)775{776 struct repaper_epd *epd = drm_to_epd(pipe->crtc.dev);777 struct spi_device *spi = epd->spi;778 unsigned int line;779 780 /*781 * This callback is not protected by drm_dev_enter/exit since we want to782 * turn off the display on regular driver unload. It's highly unlikely783 * that the underlying SPI controller is gone should this be called after784 * unplug.785 */786 787 DRM_DEBUG_DRIVER("\n");788 789 /* Nothing frame */790 for (line = 0; line < epd->height; line++)791 repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,792 REPAPER_COMPENSATE);793 794 /* 2.7" */795 if (epd->border) {796 /* Dummy line */797 repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,798 REPAPER_COMPENSATE);799 msleep(25);800 gpiod_set_value_cansleep(epd->border, 0);801 msleep(200);802 gpiod_set_value_cansleep(epd->border, 1);803 } else {804 /* Border dummy line */805 repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL,806 REPAPER_NORMAL);807 msleep(200);808 }809 810 /* not described in datasheet */811 repaper_write_val(spi, 0x0b, 0x00);812 /* Latch reset turn on */813 repaper_write_val(spi, 0x03, 0x01);814 /* Power off charge pump Vcom */815 repaper_write_val(spi, 0x05, 0x03);816 /* Power off charge pump neg voltage */817 repaper_write_val(spi, 0x05, 0x01);818 msleep(120);819 /* Discharge internal */820 repaper_write_val(spi, 0x04, 0x80);821 /* turn off all charge pumps */822 repaper_write_val(spi, 0x05, 0x00);823 /* Turn off osc */824 repaper_write_val(spi, 0x07, 0x01);825 msleep(50);826 827 power_off(epd);828}829 830static void repaper_pipe_update(struct drm_simple_display_pipe *pipe,831 struct drm_plane_state *old_state)832{833 struct drm_plane_state *state = pipe->plane.state;834 struct drm_format_conv_state fmtcnv_state = DRM_FORMAT_CONV_STATE_INIT;835 struct drm_rect rect;836 837 if (!pipe->crtc.state->active)838 return;839 840 if (drm_atomic_helper_damage_merged(old_state, state, &rect))841 repaper_fb_dirty(state->fb, &fmtcnv_state);842 843 drm_format_conv_state_release(&fmtcnv_state);844}845 846static const struct drm_simple_display_pipe_funcs repaper_pipe_funcs = {847 .mode_valid = repaper_pipe_mode_valid,848 .enable = repaper_pipe_enable,849 .disable = repaper_pipe_disable,850 .update = repaper_pipe_update,851};852 853static int repaper_connector_get_modes(struct drm_connector *connector)854{855 struct repaper_epd *epd = drm_to_epd(connector->dev);856 857 return drm_connector_helper_get_modes_fixed(connector, epd->mode);858}859 860static const struct drm_connector_helper_funcs repaper_connector_hfuncs = {861 .get_modes = repaper_connector_get_modes,862};863 864static const struct drm_connector_funcs repaper_connector_funcs = {865 .reset = drm_atomic_helper_connector_reset,866 .fill_modes = drm_helper_probe_single_connector_modes,867 .destroy = drm_connector_cleanup,868 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,869 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,870};871 872static const struct drm_mode_config_funcs repaper_mode_config_funcs = {873 .fb_create = drm_gem_fb_create_with_dirty,874 .atomic_check = drm_atomic_helper_check,875 .atomic_commit = drm_atomic_helper_commit,876};877 878static const uint32_t repaper_formats[] = {879 DRM_FORMAT_XRGB8888,880};881 882static const struct drm_display_mode repaper_e1144cs021_mode = {883 DRM_SIMPLE_MODE(128, 96, 29, 22),884};885 886static const u8 repaper_e1144cs021_cs[] = { 0x00, 0x00, 0x00, 0x00,887 0x00, 0x0f, 0xff, 0x00 };888 889static const struct drm_display_mode repaper_e1190cs021_mode = {890 DRM_SIMPLE_MODE(144, 128, 36, 32),891};892 893static const u8 repaper_e1190cs021_cs[] = { 0x00, 0x00, 0x00, 0x03,894 0xfc, 0x00, 0x00, 0xff };895 896static const struct drm_display_mode repaper_e2200cs021_mode = {897 DRM_SIMPLE_MODE(200, 96, 46, 22),898};899 900static const u8 repaper_e2200cs021_cs[] = { 0x00, 0x00, 0x00, 0x00,901 0x01, 0xff, 0xe0, 0x00 };902 903static const struct drm_display_mode repaper_e2271cs021_mode = {904 DRM_SIMPLE_MODE(264, 176, 57, 38),905};906 907static const u8 repaper_e2271cs021_cs[] = { 0x00, 0x00, 0x00, 0x7f,908 0xff, 0xfe, 0x00, 0x00 };909 910DEFINE_DRM_GEM_DMA_FOPS(repaper_fops);911 912static const struct drm_driver repaper_driver = {913 .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,914 .fops = &repaper_fops,915 DRM_GEM_DMA_DRIVER_OPS_VMAP,916 .name = "repaper",917 .desc = "Pervasive Displays RePaper e-ink panels",918 .date = "20170405",919 .major = 1,920 .minor = 0,921};922 923static const struct of_device_id repaper_of_match[] = {924 { .compatible = "pervasive,e1144cs021", .data = (void *)E1144CS021 },925 { .compatible = "pervasive,e1190cs021", .data = (void *)E1190CS021 },926 { .compatible = "pervasive,e2200cs021", .data = (void *)E2200CS021 },927 { .compatible = "pervasive,e2271cs021", .data = (void *)E2271CS021 },928 {},929};930MODULE_DEVICE_TABLE(of, repaper_of_match);931 932static const struct spi_device_id repaper_id[] = {933 { "e1144cs021", E1144CS021 },934 { "e1190cs021", E1190CS021 },935 { "e2200cs021", E2200CS021 },936 { "e2271cs021", E2271CS021 },937 { },938};939MODULE_DEVICE_TABLE(spi, repaper_id);940 941static int repaper_probe(struct spi_device *spi)942{943 const struct drm_display_mode *mode;944 const struct spi_device_id *spi_id;945 struct device *dev = &spi->dev;946 enum repaper_model model;947 const char *thermal_zone;948 struct repaper_epd *epd;949 size_t line_buffer_size;950 struct drm_device *drm;951 const void *match;952 int ret;953 954 match = device_get_match_data(dev);955 if (match) {956 model = (enum repaper_model)(uintptr_t)match;957 } else {958 spi_id = spi_get_device_id(spi);959 model = (enum repaper_model)spi_id->driver_data;960 }961 962 /* The SPI device is used to allocate dma memory */963 if (!dev->coherent_dma_mask) {964 ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32));965 if (ret) {966 dev_warn(dev, "Failed to set dma mask %d\n", ret);967 return ret;968 }969 }970 971 epd = devm_drm_dev_alloc(dev, &repaper_driver,972 struct repaper_epd, drm);973 if (IS_ERR(epd))974 return PTR_ERR(epd);975 976 drm = &epd->drm;977 978 ret = drmm_mode_config_init(drm);979 if (ret)980 return ret;981 drm->mode_config.funcs = &repaper_mode_config_funcs;982 983 epd->spi = spi;984 985 epd->panel_on = devm_gpiod_get(dev, "panel-on", GPIOD_OUT_LOW);986 if (IS_ERR(epd->panel_on)) {987 ret = PTR_ERR(epd->panel_on);988 if (ret != -EPROBE_DEFER)989 DRM_DEV_ERROR(dev, "Failed to get gpio 'panel-on'\n");990 return ret;991 }992 993 epd->discharge = devm_gpiod_get(dev, "discharge", GPIOD_OUT_LOW);994 if (IS_ERR(epd->discharge)) {995 ret = PTR_ERR(epd->discharge);996 if (ret != -EPROBE_DEFER)997 DRM_DEV_ERROR(dev, "Failed to get gpio 'discharge'\n");998 return ret;999 }1000 1001 epd->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);1002 if (IS_ERR(epd->reset)) {1003 ret = PTR_ERR(epd->reset);1004 if (ret != -EPROBE_DEFER)1005 DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n");1006 return ret;1007 }1008 1009 epd->busy = devm_gpiod_get(dev, "busy", GPIOD_IN);1010 if (IS_ERR(epd->busy)) {1011 ret = PTR_ERR(epd->busy);1012 if (ret != -EPROBE_DEFER)1013 DRM_DEV_ERROR(dev, "Failed to get gpio 'busy'\n");1014 return ret;1015 }1016 1017 if (!device_property_read_string(dev, "pervasive,thermal-zone",1018 &thermal_zone)) {1019 epd->thermal = thermal_zone_get_zone_by_name(thermal_zone);1020 if (IS_ERR(epd->thermal)) {1021 DRM_DEV_ERROR(dev, "Failed to get thermal zone: %s\n", thermal_zone);1022 return PTR_ERR(epd->thermal);1023 }1024 }1025 1026 switch (model) {1027 case E1144CS021:1028 mode = &repaper_e1144cs021_mode;1029 epd->channel_select = repaper_e1144cs021_cs;1030 epd->stage_time = 480;1031 epd->bytes_per_scan = 96 / 4;1032 epd->middle_scan = true; /* data-scan-data */1033 epd->pre_border_byte = false;1034 epd->border_byte = REPAPER_BORDER_BYTE_ZERO;1035 break;1036 1037 case E1190CS021:1038 mode = &repaper_e1190cs021_mode;1039 epd->channel_select = repaper_e1190cs021_cs;1040 epd->stage_time = 480;1041 epd->bytes_per_scan = 128 / 4 / 2;1042 epd->middle_scan = false; /* scan-data-scan */1043 epd->pre_border_byte = false;1044 epd->border_byte = REPAPER_BORDER_BYTE_SET;1045 break;1046 1047 case E2200CS021:1048 mode = &repaper_e2200cs021_mode;1049 epd->channel_select = repaper_e2200cs021_cs;1050 epd->stage_time = 480;1051 epd->bytes_per_scan = 96 / 4;1052 epd->middle_scan = true; /* data-scan-data */1053 epd->pre_border_byte = true;1054 epd->border_byte = REPAPER_BORDER_BYTE_NONE;1055 break;1056 1057 case E2271CS021:1058 epd->border = devm_gpiod_get(dev, "border", GPIOD_OUT_LOW);1059 if (IS_ERR(epd->border)) {1060 ret = PTR_ERR(epd->border);1061 if (ret != -EPROBE_DEFER)1062 DRM_DEV_ERROR(dev, "Failed to get gpio 'border'\n");1063 return ret;1064 }1065 1066 mode = &repaper_e2271cs021_mode;1067 epd->channel_select = repaper_e2271cs021_cs;1068 epd->stage_time = 630;1069 epd->bytes_per_scan = 176 / 4;1070 epd->middle_scan = true; /* data-scan-data */1071 epd->pre_border_byte = true;1072 epd->border_byte = REPAPER_BORDER_BYTE_NONE;1073 break;1074 1075 default:1076 return -ENODEV;1077 }1078 1079 epd->mode = mode;1080 epd->width = mode->hdisplay;1081 epd->height = mode->vdisplay;1082 epd->factored_stage_time = epd->stage_time;1083 1084 line_buffer_size = 2 * epd->width / 8 + epd->bytes_per_scan + 2;1085 epd->line_buffer = devm_kzalloc(dev, line_buffer_size, GFP_KERNEL);1086 if (!epd->line_buffer)1087 return -ENOMEM;1088 1089 epd->current_frame = devm_kzalloc(dev, epd->width * epd->height / 8,1090 GFP_KERNEL);1091 if (!epd->current_frame)1092 return -ENOMEM;1093 1094 drm->mode_config.min_width = mode->hdisplay;1095 drm->mode_config.max_width = mode->hdisplay;1096 drm->mode_config.min_height = mode->vdisplay;1097 drm->mode_config.max_height = mode->vdisplay;1098 1099 drm_connector_helper_add(&epd->connector, &repaper_connector_hfuncs);1100 ret = drm_connector_init(drm, &epd->connector, &repaper_connector_funcs,1101 DRM_MODE_CONNECTOR_SPI);1102 if (ret)1103 return ret;1104 1105 ret = drm_simple_display_pipe_init(drm, &epd->pipe, &repaper_pipe_funcs,1106 repaper_formats, ARRAY_SIZE(repaper_formats),1107 NULL, &epd->connector);1108 if (ret)1109 return ret;1110 1111 drm_mode_config_reset(drm);1112 1113 ret = drm_dev_register(drm, 0);1114 if (ret)1115 return ret;1116 1117 spi_set_drvdata(spi, drm);1118 1119 DRM_DEBUG_DRIVER("SPI speed: %uMHz\n", spi->max_speed_hz / 1000000);1120 1121 drm_fbdev_dma_setup(drm, 0);1122 1123 return 0;1124}1125 1126static void repaper_remove(struct spi_device *spi)1127{1128 struct drm_device *drm = spi_get_drvdata(spi);1129 1130 drm_dev_unplug(drm);1131 drm_atomic_helper_shutdown(drm);1132}1133 1134static void repaper_shutdown(struct spi_device *spi)1135{1136 drm_atomic_helper_shutdown(spi_get_drvdata(spi));1137}1138 1139static struct spi_driver repaper_spi_driver = {1140 .driver = {1141 .name = "repaper",1142 .of_match_table = repaper_of_match,1143 },1144 .id_table = repaper_id,1145 .probe = repaper_probe,1146 .remove = repaper_remove,1147 .shutdown = repaper_shutdown,1148};1149module_spi_driver(repaper_spi_driver);1150 1151MODULE_DESCRIPTION("Pervasive Displays RePaper DRM driver");1152MODULE_AUTHOR("Noralf Trønnes");1153MODULE_LICENSE("GPL");1154