diff options
Diffstat (limited to 'drivers/gpu/drm/tiny/repaper.c')
| -rw-r--r-- | drivers/gpu/drm/tiny/repaper.c | 1212 |
1 files changed, 1212 insertions, 0 deletions
diff --git a/drivers/gpu/drm/tiny/repaper.c b/drivers/gpu/drm/tiny/repaper.c new file mode 100644 index 000000000000..76d179200775 --- /dev/null +++ b/drivers/gpu/drm/tiny/repaper.c @@ -0,0 +1,1212 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * DRM driver for Pervasive Displays RePaper branded e-ink panels + * + * Copyright 2013-2017 Pervasive Displays, Inc. + * Copyright 2017 Noralf Trønnes + * + * The driver supports: + * Material Film: Aurora Mb (V231) + * Driver IC: G2 (eTC) + * + * The controller code was taken from the userspace driver: + * https://github.com/repaper/gratis + */ + +#include <linux/delay.h> +#include <linux/dma-buf.h> +#include <linux/gpio/consumer.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/sched/clock.h> +#include <linux/spi/spi.h> +#include <linux/thermal.h> + +#include <drm/drm_atomic_helper.h> +#include <drm/drm_connector.h> +#include <drm/drm_damage_helper.h> +#include <drm/drm_drv.h> +#include <drm/drm_fb_cma_helper.h> +#include <drm/drm_fb_helper.h> +#include <drm/drm_format_helper.h> +#include <drm/drm_gem_cma_helper.h> +#include <drm/drm_gem_framebuffer_helper.h> +#include <drm/drm_modes.h> +#include <drm/drm_rect.h> +#include <drm/drm_vblank.h> +#include <drm/drm_probe_helper.h> +#include <drm/drm_simple_kms_helper.h> + +#define REPAPER_RID_G2_COG_ID 0x12 + +enum repaper_model { + E1144CS021 = 1, + E1190CS021, + E2200CS021, + E2271CS021, +}; + +enum repaper_stage { /* Image pixel -> Display pixel */ + REPAPER_COMPENSATE, /* B -> W, W -> B (Current Image) */ + REPAPER_WHITE, /* B -> N, W -> W (Current Image) */ + REPAPER_INVERSE, /* B -> N, W -> B (New Image) */ + REPAPER_NORMAL /* B -> B, W -> W (New Image) */ +}; + +enum repaper_epd_border_byte { + REPAPER_BORDER_BYTE_NONE, + REPAPER_BORDER_BYTE_ZERO, + REPAPER_BORDER_BYTE_SET, +}; + +struct repaper_epd { + struct drm_device drm; + struct drm_simple_display_pipe pipe; + const struct drm_display_mode *mode; + struct drm_connector connector; + struct spi_device *spi; + + struct gpio_desc *panel_on; + struct gpio_desc *border; + struct gpio_desc *discharge; + struct gpio_desc *reset; + struct gpio_desc *busy; + + struct thermal_zone_device *thermal; + + unsigned int height; + unsigned int width; + unsigned int bytes_per_scan; + const u8 *channel_select; + unsigned int stage_time; + unsigned int factored_stage_time; + bool middle_scan; + bool pre_border_byte; + enum repaper_epd_border_byte border_byte; + + u8 *line_buffer; + void *current_frame; + + bool enabled; + bool cleared; + bool partial; +}; + +static inline struct repaper_epd *drm_to_epd(struct drm_device *drm) +{ + return container_of(drm, struct repaper_epd, drm); +} + +static int repaper_spi_transfer(struct spi_device *spi, u8 header, + const void *tx, void *rx, size_t len) +{ + void *txbuf = NULL, *rxbuf = NULL; + struct spi_transfer tr[2] = {}; + u8 *headerbuf; + int ret; + + headerbuf = kmalloc(1, GFP_KERNEL); + if (!headerbuf) + return -ENOMEM; + + headerbuf[0] = header; + tr[0].tx_buf = headerbuf; + tr[0].len = 1; + + /* Stack allocated tx? */ + if (tx && len <= 32) { + txbuf = kmemdup(tx, len, GFP_KERNEL); + if (!txbuf) { + ret = -ENOMEM; + goto out_free; + } + } + + if (rx) { + rxbuf = kmalloc(len, GFP_KERNEL); + if (!rxbuf) { + ret = -ENOMEM; + goto out_free; + } + } + + tr[1].tx_buf = txbuf ? txbuf : tx; + tr[1].rx_buf = rxbuf; + tr[1].len = len; + + ndelay(80); + ret = spi_sync_transfer(spi, tr, 2); + if (rx && !ret) + memcpy(rx, rxbuf, len); + +out_free: + kfree(headerbuf); + kfree(txbuf); + kfree(rxbuf); + + return ret; +} + +static int repaper_write_buf(struct spi_device *spi, u8 reg, + const u8 *buf, size_t len) +{ + int ret; + + ret = repaper_spi_transfer(spi, 0x70, ®, NULL, 1); + if (ret) + return ret; + + return repaper_spi_transfer(spi, 0x72, buf, NULL, len); +} + +static int repaper_write_val(struct spi_device *spi, u8 reg, u8 val) +{ + return repaper_write_buf(spi, reg, &val, 1); +} + +static int repaper_read_val(struct spi_device *spi, u8 reg) +{ + int ret; + u8 val; + + ret = repaper_spi_transfer(spi, 0x70, ®, NULL, 1); + if (ret) + return ret; + + ret = repaper_spi_transfer(spi, 0x73, NULL, &val, 1); + + return ret ? ret : val; +} + +static int repaper_read_id(struct spi_device *spi) +{ + int ret; + u8 id; + + ret = repaper_spi_transfer(spi, 0x71, NULL, &id, 1); + + return ret ? ret : id; +} + +static void repaper_spi_mosi_low(struct spi_device *spi) +{ + const u8 buf[1] = { 0 }; + + spi_write(spi, buf, 1); +} + +/* pixels on display are numbered from 1 so even is actually bits 1,3,5,... */ +static void repaper_even_pixels(struct repaper_epd *epd, u8 **pp, + const u8 *data, u8 fixed_value, const u8 *mask, + enum repaper_stage stage) +{ + unsigned int b; + + for (b = 0; b < (epd->width / 8); b++) { + if (data) { + u8 pixels = data[b] & 0xaa; + u8 pixel_mask = 0xff; + u8 p1, p2, p3, p4; + + if (mask) { + pixel_mask = (mask[b] ^ pixels) & 0xaa; + pixel_mask |= pixel_mask >> 1; + } + + switch (stage) { + case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */ + pixels = 0xaa | ((pixels ^ 0xaa) >> 1); + break; + case REPAPER_WHITE: /* B -> N, W -> W (Current) */ + pixels = 0x55 + ((pixels ^ 0xaa) >> 1); + break; + case REPAPER_INVERSE: /* B -> N, W -> B (New) */ + pixels = 0x55 | (pixels ^ 0xaa); + break; + case REPAPER_NORMAL: /* B -> B, W -> W (New) */ + pixels = 0xaa | (pixels >> 1); + break; + } + + pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55); + p1 = (pixels >> 6) & 0x03; + p2 = (pixels >> 4) & 0x03; + p3 = (pixels >> 2) & 0x03; + p4 = (pixels >> 0) & 0x03; + pixels = (p1 << 0) | (p2 << 2) | (p3 << 4) | (p4 << 6); + *(*pp)++ = pixels; + } else { + *(*pp)++ = fixed_value; + } + } +} + +/* pixels on display are numbered from 1 so odd is actually bits 0,2,4,... */ +static void repaper_odd_pixels(struct repaper_epd *epd, u8 **pp, + const u8 *data, u8 fixed_value, const u8 *mask, + enum repaper_stage stage) +{ + unsigned int b; + + for (b = epd->width / 8; b > 0; b--) { + if (data) { + u8 pixels = data[b - 1] & 0x55; + u8 pixel_mask = 0xff; + + if (mask) { + pixel_mask = (mask[b - 1] ^ pixels) & 0x55; + pixel_mask |= pixel_mask << 1; + } + + switch (stage) { + case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */ + pixels = 0xaa | (pixels ^ 0x55); + break; + case REPAPER_WHITE: /* B -> N, W -> W (Current) */ + pixels = 0x55 + (pixels ^ 0x55); + break; + case REPAPER_INVERSE: /* B -> N, W -> B (New) */ + pixels = 0x55 | ((pixels ^ 0x55) << 1); + break; + case REPAPER_NORMAL: /* B -> B, W -> W (New) */ + pixels = 0xaa | pixels; + break; + } + + pixels = (pixels & pixel_mask) | (~pixel_mask & 0x55); + *(*pp)++ = pixels; + } else { + *(*pp)++ = fixed_value; + } + } +} + +/* interleave bits: (byte)76543210 -> (16 bit).7.6.5.4.3.2.1 */ +static inline u16 repaper_interleave_bits(u16 value) +{ + value = (value | (value << 4)) & 0x0f0f; + value = (value | (value << 2)) & 0x3333; + value = (value | (value << 1)) & 0x5555; + + return value; +} + +/* pixels on display are numbered from 1 */ +static void repaper_all_pixels(struct repaper_epd *epd, u8 **pp, + const u8 *data, u8 fixed_value, const u8 *mask, + enum repaper_stage stage) +{ + unsigned int b; + + for (b = epd->width / 8; b > 0; b--) { + if (data) { + u16 pixels = repaper_interleave_bits(data[b - 1]); + u16 pixel_mask = 0xffff; + + if (mask) { + pixel_mask = repaper_interleave_bits(mask[b - 1]); + + pixel_mask = (pixel_mask ^ pixels) & 0x5555; + pixel_mask |= pixel_mask << 1; + } + + switch (stage) { + case REPAPER_COMPENSATE: /* B -> W, W -> B (Current) */ + pixels = 0xaaaa | (pixels ^ 0x5555); + break; + case REPAPER_WHITE: /* B -> N, W -> W (Current) */ + pixels = 0x5555 + (pixels ^ 0x5555); + break; + case REPAPER_INVERSE: /* B -> N, W -> B (New) */ + pixels = 0x5555 | ((pixels ^ 0x5555) << 1); + break; + case REPAPER_NORMAL: /* B -> B, W -> W (New) */ + pixels = 0xaaaa | pixels; + break; + } + + pixels = (pixels & pixel_mask) | (~pixel_mask & 0x5555); + *(*pp)++ = pixels >> 8; + *(*pp)++ = pixels; + } else { + *(*pp)++ = fixed_value; + *(*pp)++ = fixed_value; + } + } +} + +/* output one line of scan and data bytes to the display */ +static void repaper_one_line(struct repaper_epd *epd, unsigned int line, + const u8 *data, u8 fixed_value, const u8 *mask, + enum repaper_stage stage) +{ + u8 *p = epd->line_buffer; + unsigned int b; + + repaper_spi_mosi_low(epd->spi); + + if (epd->pre_border_byte) + *p++ = 0x00; + + if (epd->middle_scan) { + /* data bytes */ + repaper_odd_pixels(epd, &p, data, fixed_value, mask, stage); + + /* scan line */ + for (b = epd->bytes_per_scan; b > 0; b--) { + if (line / 4 == b - 1) + *p++ = 0x03 << (2 * (line & 0x03)); + else + *p++ = 0x00; + } + + /* data bytes */ + repaper_even_pixels(epd, &p, data, fixed_value, mask, stage); + } else { + /* + * even scan line, but as lines on display are numbered from 1, + * line: 1,3,5,... + */ + for (b = 0; b < epd->bytes_per_scan; b++) { + if (0 != (line & 0x01) && line / 8 == b) + *p++ = 0xc0 >> (line & 0x06); + else + *p++ = 0x00; + } + + /* data bytes */ + repaper_all_pixels(epd, &p, data, fixed_value, mask, stage); + + /* + * odd scan line, but as lines on display are numbered from 1, + * line: 0,2,4,6,... + */ + for (b = epd->bytes_per_scan; b > 0; b--) { + if (0 == (line & 0x01) && line / 8 == b - 1) + *p++ = 0x03 << (line & 0x06); + else + *p++ = 0x00; + } + } + + switch (epd->border_byte) { + case REPAPER_BORDER_BYTE_NONE: + break; + + case REPAPER_BORDER_BYTE_ZERO: + *p++ = 0x00; + break; + + case REPAPER_BORDER_BYTE_SET: + switch (stage) { + case REPAPER_COMPENSATE: + case REPAPER_WHITE: + case REPAPER_INVERSE: + *p++ = 0x00; + break; + case REPAPER_NORMAL: + *p++ = 0xaa; + break; + } + break; + } + + repaper_write_buf(epd->spi, 0x0a, epd->line_buffer, + p - epd->line_buffer); + + /* Output data to panel */ + repaper_write_val(epd->spi, 0x02, 0x07); + + repaper_spi_mosi_low(epd->spi); +} + +static void repaper_frame_fixed(struct repaper_epd *epd, u8 fixed_value, + enum repaper_stage stage) +{ + unsigned int line; + + for (line = 0; line < epd->height; line++) + repaper_one_line(epd, line, NULL, fixed_value, NULL, stage); +} + +static void repaper_frame_data(struct repaper_epd *epd, const u8 *image, + const u8 *mask, enum repaper_stage stage) +{ + unsigned int line; + + if (!mask) { + for (line = 0; line < epd->height; line++) { + repaper_one_line(epd, line, + &image[line * (epd->width / 8)], + 0, NULL, stage); + } + } else { + for (line = 0; line < epd->height; line++) { + size_t n = line * epd->width / 8; + + repaper_one_line(epd, line, &image[n], 0, &mask[n], + stage); + } + } +} + +static void repaper_frame_fixed_repeat(struct repaper_epd *epd, u8 fixed_value, + enum repaper_stage stage) +{ + u64 start = local_clock(); + u64 end = start + (epd->factored_stage_time * 1000 * 1000); + + do { + repaper_frame_fixed(epd, fixed_value, stage); + } while (local_clock() < end); +} + +static void repaper_frame_data_repeat(struct repaper_epd *epd, const u8 *image, + const u8 *mask, enum repaper_stage stage) +{ + u64 start = local_clock(); + u64 end = start + (epd->factored_stage_time * 1000 * 1000); + + do { + repaper_frame_data(epd, image, mask, stage); + } while (local_clock() < end); +} + +static void repaper_get_temperature(struct repaper_epd *epd) +{ + int ret, temperature = 0; + unsigned int factor10x; + + if (!epd->thermal) + return; + + ret = thermal_zone_get_temp(epd->thermal, &temperature); + if (ret) { + DRM_DEV_ERROR(&epd->spi->dev, "Failed to get temperature (%d)\n", ret); + return; + } + + temperature /= 1000; + + if (temperature <= -10) + factor10x = 170; + else if (temperature <= -5) + factor10x = 120; + else if (temperature <= 5) + factor10x = 80; + else if (temperature <= 10) + factor10x = 40; + else if (temperature <= 15) + factor10x = 30; + else if (temperature <= 20) + factor10x = 20; + else if (temperature <= 40) + factor10x = 10; + else + factor10x = 7; + + epd->factored_stage_time = epd->stage_time * factor10x / 10; +} + +static void repaper_gray8_to_mono_reversed(u8 *buf, u32 width, u32 height) +{ + u8 *gray8 = buf, *mono = buf; + int y, xb, i; + + for (y = 0; y < height; y++) + for (xb = 0; xb < width / 8; xb++) { + u8 byte = 0x00; + + for (i = 0; i < 8; i++) { + int x = xb * 8 + i; + + byte >>= 1; + if (gray8[y * width + x] >> 7) + byte |= BIT(7); + } + *mono++ = byte; + } +} + +static int repaper_fb_dirty(struct drm_framebuffer *fb) +{ + struct drm_gem_cma_object *cma_obj = drm_fb_cma_get_gem_obj(fb, 0); + struct dma_buf_attachment *import_attach = cma_obj->base.import_attach; + struct repaper_epd *epd = drm_to_epd(fb->dev); + struct drm_rect clip; + int idx, ret = 0; + u8 *buf = NULL; + + if (!epd->enabled) + return 0; + + if (!drm_dev_enter(fb->dev, &idx)) + return -ENODEV; + + /* repaper can't do partial updates */ + clip.x1 = 0; + clip.x2 = fb->width; + clip.y1 = 0; + clip.y2 = fb->height; + + repaper_get_temperature(epd); + + DRM_DEBUG("Flushing [FB:%d] st=%ums\n", fb->base.id, + epd->factored_stage_time); + + buf = kmalloc_array(fb->width, fb->height, GFP_KERNEL); + if (!buf) { + ret = -ENOMEM; + goto out_exit; + } + + if (import_attach) { + ret = dma_buf_begin_cpu_access(import_attach->dmabuf, + DMA_FROM_DEVICE); + if (ret) + goto out_free; + } + + drm_fb_xrgb8888_to_gray8(buf, cma_obj->vaddr, fb, &clip); + + if (import_attach) { + ret = dma_buf_end_cpu_access(import_attach->dmabuf, + DMA_FROM_DEVICE); + if (ret) + goto out_free; + } + + repaper_gray8_to_mono_reversed(buf, fb->width, fb->height); + + if (epd->partial) { + repaper_frame_data_repeat(epd, buf, epd->current_frame, + REPAPER_NORMAL); + } else if (epd->cleared) { + repaper_frame_data_repeat(epd, epd->current_frame, NULL, + REPAPER_COMPENSATE); + repaper_frame_data_repeat(epd, epd->current_frame, NULL, + REPAPER_WHITE); + repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE); + repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL); + + epd->partial = true; + } else { + /* Clear display (anything -> white) */ + repaper_frame_fixed_repeat(epd, 0xff, REPAPER_COMPENSATE); + repaper_frame_fixed_repeat(epd, 0xff, REPAPER_WHITE); + repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_INVERSE); + repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_NORMAL); + + /* Assuming a clear (white) screen output an image */ + repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_COMPENSATE); + repaper_frame_fixed_repeat(epd, 0xaa, REPAPER_WHITE); + repaper_frame_data_repeat(epd, buf, NULL, REPAPER_INVERSE); + repaper_frame_data_repeat(epd, buf, NULL, REPAPER_NORMAL); + + epd->cleared = true; + epd->partial = true; + } + + memcpy(epd->current_frame, buf, fb->width * fb->height / 8); + + /* + * An extra frame write is needed if pixels are set in the bottom line, + * or else grey lines rises up from the pixels + */ + if (epd->pre_border_byte) { + unsigned int x; + + for (x = 0; x < (fb->width / 8); x++) + if (buf[x + (fb->width * (fb->height - 1) / 8)]) { + repaper_frame_data_repeat(epd, buf, + epd->current_frame, + REPAPER_NORMAL); + break; + } + } + +out_free: + kfree(buf); +out_exit: + drm_dev_exit(idx); + + return ret; +} + +static void power_off(struct repaper_epd *epd) +{ + /* Turn off power and all signals */ + gpiod_set_value_cansleep(epd->reset, 0); + gpiod_set_value_cansleep(epd->panel_on, 0); + if (epd->border) + gpiod_set_value_cansleep(epd->border, 0); + + /* Ensure SPI MOSI and CLOCK are Low before CS Low */ + repaper_spi_mosi_low(epd->spi); + + /* Discharge pulse */ + gpiod_set_value_cansleep(epd->discharge, 1); + msleep(150); + gpiod_set_value_cansleep(epd->discharge, 0); +} + +static void repaper_pipe_enable(struct drm_simple_display_pipe *pipe, + struct drm_crtc_state *crtc_state, + struct drm_plane_state *plane_state) +{ + struct repaper_epd *epd = drm_to_epd(pipe->crtc.dev); + struct spi_device *spi = epd->spi; + struct device *dev = &spi->dev; + bool dc_ok = false; + int i, ret, idx; + + if (!drm_dev_enter(pipe->crtc.dev, &idx)) + return; + + DRM_DEBUG_DRIVER("\n"); + + /* Power up sequence */ + gpiod_set_value_cansleep(epd->reset, 0); + gpiod_set_value_cansleep(epd->panel_on, 0); + gpiod_set_value_cansleep(epd->discharge, 0); + if (epd->border) + gpiod_set_value_cansleep(epd->border, 0); + repaper_spi_mosi_low(spi); + usleep_range(5000, 10000); + + gpiod_set_value_cansleep(epd->panel_on, 1); + /* + * This delay comes from the repaper.org userspace driver, it's not + * mentioned in the datasheet. + */ + usleep_range(10000, 15000); + gpiod_set_value_cansleep(epd->reset, 1); + if (epd->border) + gpiod_set_value_cansleep(epd->border, 1); + usleep_range(5000, 10000); + gpiod_set_value_cansleep(epd->reset, 0); + usleep_range(5000, 10000); + gpiod_set_value_cansleep(epd->reset, 1); + usleep_range(5000, 10000); + + /* Wait for COG to become ready */ + for (i = 100; i > 0; i--) { + if (!gpiod_get_value_cansleep(epd->busy)) + break; + + usleep_range(10, 100); + } + + if (!i) { + DRM_DEV_ERROR(dev, "timeout waiting for panel to become ready.\n"); + power_off(epd); + goto out_exit; + } + + repaper_read_id(spi); + ret = repaper_read_id(spi); + if (ret != REPAPER_RID_G2_COG_ID) { + if (ret < 0) + dev_err(dev, "failed to read chip (%d)\n", ret); + else + dev_err(dev, "wrong COG ID 0x%02x\n", ret); + power_off(epd); + goto out_exit; + } + + /* Disable OE */ + repaper_write_val(spi, 0x02, 0x40); + + ret = repaper_read_val(spi, 0x0f); + if (ret < 0 || !(ret & 0x80)) { + if (ret < 0) + DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret); + else + DRM_DEV_ERROR(dev, "panel is reported broken\n"); + power_off(epd); + goto out_exit; + } + + /* Power saving mode */ + repaper_write_val(spi, 0x0b, 0x02); + /* Channel select */ + repaper_write_buf(spi, 0x01, epd->channel_select, 8); + /* High power mode osc */ + repaper_write_val(spi, 0x07, 0xd1); + /* Power setting */ + repaper_write_val(spi, 0x08, 0x02); + /* Vcom level */ + repaper_write_val(spi, 0x09, 0xc2); + /* Power setting */ + repaper_write_val(spi, 0x04, 0x03); + /* Driver latch on */ + repaper_write_val(spi, 0x03, 0x01); + /* Driver latch off */ + repaper_write_val(spi, 0x03, 0x00); + usleep_range(5000, 10000); + + /* Start chargepump */ + for (i = 0; i < 4; ++i) { + /* Charge pump positive voltage on - VGH/VDL on */ + repaper_write_val(spi, 0x05, 0x01); + msleep(240); + + /* Charge pump negative voltage on - VGL/VDL on */ + repaper_write_val(spi, 0x05, 0x03); + msleep(40); + + /* Charge pump Vcom on - Vcom driver on */ + repaper_write_val(spi, 0x05, 0x0f); + msleep(40); + + /* check DC/DC */ + ret = repaper_read_val(spi, 0x0f); + if (ret < 0) { + DRM_DEV_ERROR(dev, "failed to read chip (%d)\n", ret); + power_off(epd); + goto out_exit; + } + + if (ret & 0x40) { + dc_ok = true; + break; + } + } + + if (!dc_ok) { + DRM_DEV_ERROR(dev, "dc/dc failed\n"); + power_off(epd); + goto out_exit; + } + + /* + * Output enable to disable + * The userspace driver sets this to 0x04, but the datasheet says 0x06 + */ + repaper_write_val(spi, 0x02, 0x04); + + epd->enabled = true; + epd->partial = false; +out_exit: + drm_dev_exit(idx); +} + +static void repaper_pipe_disable(struct drm_simple_display_pipe *pipe) +{ + struct repaper_epd *epd = drm_to_epd(pipe->crtc.dev); + struct spi_device *spi = epd->spi; + unsigned int line; + + /* + * This callback is not protected by drm_dev_enter/exit since we want to + * turn off the display on regular driver unload. It's highly unlikely + * that the underlying SPI controller is gone should this be called after + * unplug. + */ + + if (!epd->enabled) + return; + + DRM_DEBUG_DRIVER("\n"); + + epd->enabled = false; + + /* Nothing frame */ + for (line = 0; line < epd->height; line++) + repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL, + REPAPER_COMPENSATE); + + /* 2.7" */ + if (epd->border) { + /* Dummy line */ + repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL, + REPAPER_COMPENSATE); + msleep(25); + gpiod_set_value_cansleep(epd->border, 0); + msleep(200); + gpiod_set_value_cansleep(epd->border, 1); + } else { + /* Border dummy line */ + repaper_one_line(epd, 0x7fffu, NULL, 0x00, NULL, + REPAPER_NORMAL); + msleep(200); + } + + /* not described in datasheet */ + repaper_write_val(spi, 0x0b, 0x00); + /* Latch reset turn on */ + repaper_write_val(spi, 0x03, 0x01); + /* Power off charge pump Vcom */ + repaper_write_val(spi, 0x05, 0x03); + /* Power off charge pump neg voltage */ + repaper_write_val(spi, 0x05, 0x01); + msleep(120); + /* Discharge internal */ + repaper_write_val(spi, 0x04, 0x80); + /* turn off all charge pumps */ + repaper_write_val(spi, 0x05, 0x00); + /* Turn off osc */ + repaper_write_val(spi, 0x07, 0x01); + msleep(50); + + power_off(epd); +} + +static void repaper_pipe_update(struct drm_simple_display_pipe *pipe, + struct drm_plane_state *old_state) +{ + struct drm_plane_state *state = pipe->plane.state; + struct drm_crtc *crtc = &pipe->crtc; + struct drm_rect rect; + + if (drm_atomic_helper_damage_merged(old_state, state, &rect)) + repaper_fb_dirty(state->fb); + + if (crtc->state->event) { + spin_lock_irq(&crtc->dev->event_lock); + drm_crtc_send_vblank_event(crtc, crtc->state->event); + spin_unlock_irq(&crtc->dev->event_lock); + crtc->state->event = NULL; + } +} + +static const struct drm_simple_display_pipe_funcs repaper_pipe_funcs = { + .enable = repaper_pipe_enable, + .disable = repaper_pipe_disable, + .update = repaper_pipe_update, + .prepare_fb = drm_gem_fb_simple_display_pipe_prepare_fb, +}; + +static int repaper_connector_get_modes(struct drm_connector *connector) +{ + struct repaper_epd *epd = drm_to_epd(connector->dev); + struct drm_display_mode *mode; + + mode = drm_mode_duplicate(connector->dev, epd->mode); + if (!mode) { + DRM_ERROR("Failed to duplicate mode\n"); + return 0; + } + + drm_mode_set_name(mode); + mode->type |= DRM_MODE_TYPE_PREFERRED; + drm_mode_probed_add(connector, mode); + + connector->display_info.width_mm = mode->width_mm; + connector->display_info.height_mm = mode->height_mm; + + return 1; +} + +static const struct drm_connector_helper_funcs repaper_connector_hfuncs = { + .get_modes = repaper_connector_get_modes, +}; + +static const struct drm_connector_funcs repaper_connector_funcs = { + .reset = drm_atomic_helper_connector_reset, + .fill_modes = drm_helper_probe_single_connector_modes, + .destroy = drm_connector_cleanup, + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, +}; + +static const struct drm_mode_config_funcs repaper_mode_config_funcs = { + .fb_create = drm_gem_fb_create_with_dirty, + .atomic_check = drm_atomic_helper_check, + .atomic_commit = drm_atomic_helper_commit, +}; + +static void repaper_release(struct drm_device *drm) +{ + struct repaper_epd *epd = drm_to_epd(drm); + + DRM_DEBUG_DRIVER("\n"); + + drm_mode_config_cleanup(drm); + drm_dev_fini(drm); + kfree(epd); +} + +static const uint32_t repaper_formats[] = { + DRM_FORMAT_XRGB8888, +}; + +static const struct drm_display_mode repaper_e1144cs021_mode = { + DRM_SIMPLE_MODE(128, 96, 29, 22), +}; + +static const u8 repaper_e1144cs021_cs[] = { 0x00, 0x00, 0x00, 0x00, + 0x00, 0x0f, 0xff, 0x00 }; + +static const struct drm_display_mode repaper_e1190cs021_mode = { + DRM_SIMPLE_MODE(144, 128, 36, 32), +}; + +static const u8 repaper_e1190cs021_cs[] = { 0x00, 0x00, 0x00, 0x03, + 0xfc, 0x00, 0x00, 0xff }; + +static const struct drm_display_mode repaper_e2200cs021_mode = { + DRM_SIMPLE_MODE(200, 96, 46, 22), +}; + +static const u8 repaper_e2200cs021_cs[] = { 0x00, 0x00, 0x00, 0x00, + 0x01, 0xff, 0xe0, 0x00 }; + +static const struct drm_display_mode repaper_e2271cs021_mode = { + DRM_SIMPLE_MODE(264, 176, 57, 38), +}; + +static const u8 repaper_e2271cs021_cs[] = { 0x00, 0x00, 0x00, 0x7f, + 0xff, 0xfe, 0x00, 0x00 }; + +DEFINE_DRM_GEM_CMA_FOPS(repaper_fops); + +static struct drm_driver repaper_driver = { + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC, + .fops = &repaper_fops, + .release = repaper_release, + DRM_GEM_CMA_VMAP_DRIVER_OPS, + .name = "repaper", + .desc = "Pervasive Displays RePaper e-ink panels", + .date = "20170405", + .major = 1, + .minor = 0, +}; + +static const struct of_device_id repaper_of_match[] = { + { .compatible = "pervasive,e1144cs021", .data = (void *)E1144CS021 }, + { .compatible = "pervasive,e1190cs021", .data = (void *)E1190CS021 }, + { .compatible = "pervasive,e2200cs021", .data = (void *)E2200CS021 }, + { .compatible = "pervasive,e2271cs021", .data = (void *)E2271CS021 }, + {}, +}; +MODULE_DEVICE_TABLE(of, repaper_of_match); + +static const struct spi_device_id repaper_id[] = { + { "e1144cs021", E1144CS021 }, + { "e1190cs021", E1190CS021 }, + { "e2200cs021", E2200CS021 }, + { "e2271cs021", E2271CS021 }, + { }, +}; +MODULE_DEVICE_TABLE(spi, repaper_id); + +static int repaper_probe(struct spi_device *spi) +{ + const struct drm_display_mode *mode; + const struct spi_device_id *spi_id; + const struct of_device_id *match; + struct device *dev = &spi->dev; + enum repaper_model model; + const char *thermal_zone; + struct repaper_epd *epd; + size_t line_buffer_size; + struct drm_device *drm; + int ret; + + match = of_match_device(repaper_of_match, dev); + if (match) { + model = (enum repaper_model)match->data; + } else { + spi_id = spi_get_device_id(spi); + model = spi_id->driver_data; + } + + /* The SPI device is used to allocate dma memory */ + if (!dev->coherent_dma_mask) { + ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(32)); + if (ret) { + dev_warn(dev, "Failed to set dma mask %d\n", ret); + return ret; + } + } + + epd = kzalloc(sizeof(*epd), GFP_KERNEL); + if (!epd) + return -ENOMEM; + + drm = &epd->drm; + + ret = devm_drm_dev_init(dev, drm, &repaper_driver); + if (ret) { + kfree(epd); + return ret; + } + + drm_mode_config_init(drm); + drm->mode_config.funcs = &repaper_mode_config_funcs; + + epd->spi = spi; + + epd->panel_on = devm_gpiod_get(dev, "panel-on", GPIOD_OUT_LOW); + if (IS_ERR(epd->panel_on)) { + ret = PTR_ERR(epd->panel_on); + if (ret != -EPROBE_DEFER) + DRM_DEV_ERROR(dev, "Failed to get gpio 'panel-on'\n"); + return ret; + } + + epd->discharge = devm_gpiod_get(dev, "discharge", GPIOD_OUT_LOW); + if (IS_ERR(epd->discharge)) { + ret = PTR_ERR(epd->discharge); + if (ret != -EPROBE_DEFER) + DRM_DEV_ERROR(dev, "Failed to get gpio 'discharge'\n"); + return ret; + } + + epd->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW); + if (IS_ERR(epd->reset)) { + ret = PTR_ERR(epd->reset); + if (ret != -EPROBE_DEFER) + DRM_DEV_ERROR(dev, "Failed to get gpio 'reset'\n"); + return ret; + } + + epd->busy = devm_gpiod_get(dev, "busy", GPIOD_IN); + if (IS_ERR(epd->busy)) { + ret = PTR_ERR(epd->busy); + if (ret != -EPROBE_DEFER) + DRM_DEV_ERROR(dev, "Failed to get gpio 'busy'\n"); + return ret; + } + + if (!device_property_read_string(dev, "pervasive,thermal-zone", + &thermal_zone)) { + epd->thermal = thermal_zone_get_zone_by_name(thermal_zone); + if (IS_ERR(epd->thermal)) { + DRM_DEV_ERROR(dev, "Failed to get thermal zone: %s\n", thermal_zone); + return PTR_ERR(epd->thermal); + } + } + + switch (model) { + case E1144CS021: + mode = &repaper_e1144cs021_mode; + epd->channel_select = repaper_e1144cs021_cs; + epd->stage_time = 480; + epd->bytes_per_scan = 96 / 4; + epd->middle_scan = true; /* data-scan-data */ + epd->pre_border_byte = false; + epd->border_byte = REPAPER_BORDER_BYTE_ZERO; + break; + + case E1190CS021: + mode = &repaper_e1190cs021_mode; + epd->channel_select = repaper_e1190cs021_cs; + epd->stage_time = 480; + epd->bytes_per_scan = 128 / 4 / 2; + epd->middle_scan = false; /* scan-data-scan */ + epd->pre_border_byte = false; + epd->border_byte = REPAPER_BORDER_BYTE_SET; + break; + + case E2200CS021: + mode = &repaper_e2200cs021_mode; + epd->channel_select = repaper_e2200cs021_cs; + epd->stage_time = 480; + epd->bytes_per_scan = 96 / 4; + epd->middle_scan = true; /* data-scan-data */ + epd->pre_border_byte = true; + epd->border_byte = REPAPER_BORDER_BYTE_NONE; + break; + + case E2271CS021: + epd->border = devm_gpiod_get(dev, "border", GPIOD_OUT_LOW); + if (IS_ERR(epd->border)) { + ret = PTR_ERR(epd->border); + if (ret != -EPROBE_DEFER) + DRM_DEV_ERROR(dev, "Failed to get gpio 'border'\n"); + return ret; + } + + mode = &repaper_e2271cs021_mode; + epd->channel_select = repaper_e2271cs021_cs; + epd->stage_time = 630; + epd->bytes_per_scan = 176 / 4; + epd->middle_scan = true; /* data-scan-data */ + epd->pre_border_byte = true; + epd->border_byte = REPAPER_BORDER_BYTE_NONE; + break; + + default: + return -ENODEV; + } + + epd->mode = mode; + epd->width = mode->hdisplay; + epd->height = mode->vdisplay; + epd->factored_stage_time = epd->stage_time; + + line_buffer_size = 2 * epd->width / 8 + epd->bytes_per_scan + 2; + epd->line_buffer = devm_kzalloc(dev, line_buffer_size, GFP_KERNEL); + if (!epd->line_buffer) + return -ENOMEM; + + epd->current_frame = devm_kzalloc(dev, epd->width * epd->height / 8, + GFP_KERNEL); + if (!epd->current_frame) + return -ENOMEM; + + drm->mode_config.min_width = mode->hdisplay; + drm->mode_config.max_width = mode->hdisplay; + drm->mode_config.min_height = mode->vdisplay; + drm->mode_config.max_height = mode->vdisplay; + + drm_connector_helper_add(&epd->connector, &repaper_connector_hfuncs); + ret = drm_connector_init(drm, &epd->connector, &repaper_connector_funcs, + DRM_MODE_CONNECTOR_SPI); + if (ret) + return ret; + + ret = drm_simple_display_pipe_init(drm, &epd->pipe, &repaper_pipe_funcs, + repaper_formats, ARRAY_SIZE(repaper_formats), + NULL, &epd->connector); + if (ret) + return ret; + + drm_mode_config_reset(drm); + + ret = drm_dev_register(drm, 0); + if (ret) + return ret; + + spi_set_drvdata(spi, drm); + + DRM_DEBUG_DRIVER("SPI speed: %uMHz\n", spi->max_speed_hz / 1000000); + + drm_fbdev_generic_setup(drm, 0); + + return 0; +} + +static int repaper_remove(struct spi_device *spi) +{ + struct drm_device *drm = spi_get_drvdata(spi); + + drm_dev_unplug(drm); + drm_atomic_helper_shutdown(drm); + + return 0; +} + +static void repaper_shutdown(struct spi_device *spi) +{ + drm_atomic_helper_shutdown(spi_get_drvdata(spi)); +} + +static struct spi_driver repaper_spi_driver = { + .driver = { + .name = "repaper", + .owner = THIS_MODULE, + .of_match_table = repaper_of_match, + }, + .id_table = repaper_id, + .probe = repaper_probe, + .remove = repaper_remove, + .shutdown = repaper_shutdown, +}; +module_spi_driver(repaper_spi_driver); + +MODULE_DESCRIPTION("Pervasive Displays RePaper DRM driver"); +MODULE_AUTHOR("Noralf Trønnes"); +MODULE_LICENSE("GPL"); |