diff options
Diffstat (limited to 'drivers/gpu/drm/tiny/st7571-i2c.c')
| -rw-r--r-- | drivers/gpu/drm/tiny/st7571-i2c.c | 1002 |
1 files changed, 0 insertions, 1002 deletions
diff --git a/drivers/gpu/drm/tiny/st7571-i2c.c b/drivers/gpu/drm/tiny/st7571-i2c.c deleted file mode 100644 index dc410ec41baf..000000000000 --- a/drivers/gpu/drm/tiny/st7571-i2c.c +++ /dev/null @@ -1,1002 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later -/* - * Driver for Sitronix ST7571, a 4 level gray scale dot matrix LCD controller - * - * Copyright (C) 2025 Marcus Folkesson <marcus.folkesson@gmail.com> - */ - -#include <linux/bitfield.h> -#include <linux/delay.h> -#include <linux/gpio/consumer.h> -#include <linux/i2c.h> -#include <linux/module.h> -#include <linux/regmap.h> - -#include <drm/clients/drm_client_setup.h> -#include <drm/drm_atomic.h> -#include <drm/drm_atomic_helper.h> -#include <drm/drm_connector.h> -#include <drm/drm_crtc_helper.h> -#include <drm/drm_damage_helper.h> -#include <drm/drm_drv.h> -#include <drm/drm_encoder.h> -#include <drm/drm_fb_helper.h> -#include <drm/drm_fbdev_shmem.h> -#include <drm/drm_fourcc.h> -#include <drm/drm_framebuffer.h> -#include <drm/drm_gem_atomic_helper.h> -#include <drm/drm_gem_framebuffer_helper.h> -#include <drm/drm_gem_shmem_helper.h> -#include <drm/drm_modeset_helper_vtables.h> -#include <drm/drm_module.h> -#include <drm/drm_plane.h> -#include <drm/drm_probe_helper.h> - -#include <video/display_timing.h> -#include <video/of_display_timing.h> - -#define ST7571_COMMAND_MODE (0x00) -#define ST7571_DATA_MODE (0x40) - -/* Normal mode command set */ -#define ST7571_DISPLAY_OFF (0xae) -#define ST7571_DISPLAY_ON (0xaf) -#define ST7571_OSC_ON (0xab) -#define ST7571_SET_COLUMN_LSB(c) (0x00 | FIELD_PREP(GENMASK(3, 0), (c))) -#define ST7571_SET_COLUMN_MSB(c) (0x10 | FIELD_PREP(GENMASK(2, 0), (c) >> 4)) -#define ST7571_SET_COM0_LSB(x) (FIELD_PREP(GENMASK(6, 0), (x))) -#define ST7571_SET_COM0_MSB (0x44) -#define ST7571_SET_COM_SCAN_DIR(d) (0xc0 | FIELD_PREP(GENMASK(3, 3), (d))) -#define ST7571_SET_CONTRAST_LSB(c) (FIELD_PREP(GENMASK(5, 0), (c))) -#define ST7571_SET_CONTRAST_MSB (0x81) -#define ST7571_SET_DISPLAY_DUTY_LSB(d) (FIELD_PREP(GENMASK(7, 0), (d))) -#define ST7571_SET_DISPLAY_DUTY_MSB (0x48) -#define ST7571_SET_ENTIRE_DISPLAY_ON(p) (0xa4 | FIELD_PREP(GENMASK(0, 0), (p))) -#define ST7571_SET_LCD_BIAS(b) (0x50 | FIELD_PREP(GENMASK(2, 0), (b))) -#define ST7571_SET_MODE_LSB(m) (FIELD_PREP(GENMASK(7, 2), (m))) -#define ST7571_SET_MODE_MSB (0x38) -#define ST7571_SET_PAGE(p) (0xb0 | FIELD_PREP(GENMASK(3, 0), (p))) -#define ST7571_SET_POWER(p) (0x28 | FIELD_PREP(GENMASK(2, 0), (p))) -#define ST7571_SET_REGULATOR_REG(r) (0x20 | FIELD_PREP(GENMASK(2, 0), (r))) -#define ST7571_SET_REVERSE(r) (0xa6 | FIELD_PREP(GENMASK(0, 0), (r))) -#define ST7571_SET_SEG_SCAN_DIR(d) (0xa0 | FIELD_PREP(GENMASK(0, 0), (d))) -#define ST7571_SET_START_LINE_LSB(l) (FIELD_PREP(GENMASK(6, 0), (l))) -#define ST7571_SET_START_LINE_MSB (0x40) - -/* Extension command set 3 */ -#define ST7571_COMMAND_SET_3 (0x7b) -#define ST7571_SET_COLOR_MODE(c) (0x10 | FIELD_PREP(GENMASK(0, 0), (c))) -#define ST7571_COMMAND_SET_NORMAL (0x00) - -#define ST7571_PAGE_HEIGHT 8 - -#define DRIVER_NAME "st7571" -#define DRIVER_DESC "ST7571 DRM driver" -#define DRIVER_MAJOR 1 -#define DRIVER_MINOR 0 - -enum st7571_color_mode { - ST7571_COLOR_MODE_GRAY = 0, - ST7571_COLOR_MODE_BLACKWHITE = 1, -}; - -struct st7571_device; - -struct st7571_panel_constraints { - u32 min_nlines; - u32 max_nlines; - u32 min_ncols; - u32 max_ncols; - bool support_grayscale; -}; - -struct st7571_panel_data { - int (*init)(struct st7571_device *st7571); - struct st7571_panel_constraints constraints; -}; - -struct st7571_panel_format { - void (*prepare_buffer)(struct st7571_device *st7571, - const struct iosys_map *vmap, - struct drm_framebuffer *fb, - struct drm_rect *rect, - struct drm_format_conv_state *fmtcnv_state); - int (*update_rect)(struct drm_framebuffer *fb, struct drm_rect *rect); - enum st7571_color_mode mode; - const u8 nformats; - const u32 formats[]; -}; - -struct st7571_device { - struct drm_device dev; - - struct drm_plane primary_plane; - struct drm_crtc crtc; - struct drm_encoder encoder; - struct drm_connector connector; - - struct drm_display_mode mode; - - const struct st7571_panel_format *pformat; - const struct st7571_panel_data *pdata; - struct i2c_client *client; - struct gpio_desc *reset; - struct regmap *regmap; - - /* - * Depending on the hardware design, the acknowledge signal may be hard to - * recognize as a valid logic "0" level. - * Therefor, ignore NAK if possible to stay compatible with most hardware designs - * and off-the-shelf panels out there. - * - * From section 6.4 MICROPOCESSOR INTERFACE section in the datasheet: - * - * "By connecting SDA_OUT to SDA_IN externally, the SDA line becomes fully - * I2C interface compatible. - * Separating acknowledge-output from serial data - * input is advantageous for chip-on-glass (COG) applications. In COG - * applications, the ITO resistance and the pull-up resistor will form a - * voltage divider, which affects acknowledge-signal level. Larger ITO - * resistance will raise the acknowledged-signal level and system cannot - * recognize this level as a valid logic “0” level. By separating SDA_IN from - * SDA_OUT, the IC can be used in a mode that ignores the acknowledge-bit. - * For applications which check acknowledge-bit, it is necessary to minimize - * the ITO resistance of the SDA_OUT trace to guarantee a valid low level." - * - */ - bool ignore_nak; - - bool grayscale; - u32 height_mm; - u32 width_mm; - u32 startline; - u32 nlines; - u32 ncols; - u32 bpp; - - /* Intermediate buffer in LCD friendly format */ - u8 *hwbuf; - - /* Row of (transformed) pixels ready to be written to the display */ - u8 *row; -}; - -static inline struct st7571_device *drm_to_st7571(struct drm_device *dev) -{ - return container_of(dev, struct st7571_device, dev); -} - -static int st7571_regmap_write(void *context, const void *data, size_t count) -{ - struct i2c_client *client = context; - struct st7571_device *st7571 = i2c_get_clientdata(client); - int ret; - - struct i2c_msg msg = { - .addr = st7571->client->addr, - .flags = st7571->ignore_nak ? I2C_M_IGNORE_NAK : 0, - .len = count, - .buf = (u8 *)data - }; - - ret = i2c_transfer(st7571->client->adapter, &msg, 1); - - /* - * Unfortunately, there is no way to check if the transfer failed because of - * a NAK or something else as I2C bus drivers use different return values for NAK. - * - * However, if the transfer fails and ignore_nak is set, we know it is an error. - */ - if (ret < 0 && st7571->ignore_nak) - return ret; - - return 0; -} - -/* The st7571 driver does not read registers but regmap expects a .read */ -static int st7571_regmap_read(void *context, const void *reg_buf, - size_t reg_size, void *val_buf, size_t val_size) -{ - return -EOPNOTSUPP; -} - -static int st7571_send_command_list(struct st7571_device *st7571, - const u8 *cmd_list, size_t len) -{ - int ret; - - for (int i = 0; i < len; i++) { - ret = regmap_write(st7571->regmap, ST7571_COMMAND_MODE, cmd_list[i]); - if (ret < 0) - return ret; - } - - return ret; -} - -static inline u8 st7571_transform_xy(const char *p, int x, int y) -{ - int xrest = x % 8; - u8 result = 0; - - /* - * Transforms an (x, y) pixel coordinate into a vertical 8-bit - * column from the framebuffer. It calculates the corresponding byte in the - * framebuffer, extracts the bit at the given x position across 8 consecutive - * rows, and packs those bits into a single byte. - * - * Return an 8-bit value representing a vertical column of pixels. - */ - x = x / 8; - y = (y / 8) * 8; - - for (int i = 0; i < 8; i++) { - int row_idx = y + i; - u8 byte = p[row_idx * 16 + x]; - u8 bit = (byte >> xrest) & 1; - - result |= (bit << i); - } - - return result; -} - -static int st7571_set_position(struct st7571_device *st7571, int x, int y) -{ - u8 cmd_list[] = { - ST7571_SET_COLUMN_LSB(x), - ST7571_SET_COLUMN_MSB(x), - ST7571_SET_PAGE(y / ST7571_PAGE_HEIGHT), - }; - - return st7571_send_command_list(st7571, cmd_list, ARRAY_SIZE(cmd_list)); -} - -static int st7571_fb_clear_screen(struct st7571_device *st7571) -{ - u32 npixels = st7571->ncols * round_up(st7571->nlines, ST7571_PAGE_HEIGHT) * st7571->bpp; - char pixelvalue = 0x00; - - for (int i = 0; i < npixels; i++) - regmap_bulk_write(st7571->regmap, ST7571_DATA_MODE, &pixelvalue, 1); - - return 0; -} - -static void st7571_prepare_buffer_monochrome(struct st7571_device *st7571, - const struct iosys_map *vmap, - struct drm_framebuffer *fb, - struct drm_rect *rect, - struct drm_format_conv_state *fmtcnv_state) -{ - unsigned int dst_pitch; - struct iosys_map dst; - u32 size; - - switch (fb->format->format) { - case DRM_FORMAT_XRGB8888: - dst_pitch = DIV_ROUND_UP(drm_rect_width(rect), 8); - iosys_map_set_vaddr(&dst, st7571->hwbuf); - - drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, vmap, fb, rect, fmtcnv_state); - break; - - case DRM_FORMAT_R1: - size = (rect->x2 - rect->x1) * (rect->y2 - rect->y1) / 8; - memcpy(st7571->hwbuf, vmap->vaddr, size); - break; - } -} - -static void st7571_prepare_buffer_grayscale(struct st7571_device *st7571, - const struct iosys_map *vmap, - struct drm_framebuffer *fb, - struct drm_rect *rect, - struct drm_format_conv_state *fmtcnv_state) -{ - u32 size = (rect->x2 - rect->x1) * (rect->y2 - rect->y1) / 8; - unsigned int dst_pitch; - struct iosys_map dst; - - switch (fb->format->format) { - case DRM_FORMAT_XRGB8888: /* Only support XRGB8888 in monochrome mode */ - dst_pitch = DIV_ROUND_UP(drm_rect_width(rect), 8); - iosys_map_set_vaddr(&dst, st7571->hwbuf); - - drm_fb_xrgb8888_to_mono(&dst, &dst_pitch, vmap, fb, rect, fmtcnv_state); - break; - - case DRM_FORMAT_R1: - size = (rect->x2 - rect->x1) * (rect->y2 - rect->y1) / 8; - memcpy(st7571->hwbuf, vmap->vaddr, size); - break; - - case DRM_FORMAT_R2: - size = (rect->x2 - rect->x1) * (rect->y2 - rect->y1) / 4; - memcpy(st7571->hwbuf, vmap->vaddr, size); - break; - }; -} - -static int st7571_fb_update_rect_monochrome(struct drm_framebuffer *fb, struct drm_rect *rect) -{ - struct st7571_device *st7571 = drm_to_st7571(fb->dev); - char *row = st7571->row; - - /* Align y to display page boundaries */ - rect->y1 = round_down(rect->y1, ST7571_PAGE_HEIGHT); - rect->y2 = min_t(unsigned int, round_up(rect->y2, ST7571_PAGE_HEIGHT), st7571->nlines); - - for (int y = rect->y1; y < rect->y2; y += ST7571_PAGE_HEIGHT) { - for (int x = rect->x1; x < rect->x2; x++) - row[x] = st7571_transform_xy(st7571->hwbuf, x, y); - - st7571_set_position(st7571, rect->x1, y); - - /* TODO: Investige why we can't write multiple bytes at once */ - for (int x = rect->x1; x < rect->x2; x++) - regmap_bulk_write(st7571->regmap, ST7571_DATA_MODE, row + x, 1); - } - - return 0; -} - -static int st7571_fb_update_rect_grayscale(struct drm_framebuffer *fb, struct drm_rect *rect) -{ - struct st7571_device *st7571 = drm_to_st7571(fb->dev); - u32 format = fb->format->format; - char *row = st7571->row; - int x1; - int x2; - - /* Align y to display page boundaries */ - rect->y1 = round_down(rect->y1, ST7571_PAGE_HEIGHT); - rect->y2 = min_t(unsigned int, round_up(rect->y2, ST7571_PAGE_HEIGHT), st7571->nlines); - - switch (format) { - case DRM_FORMAT_XRGB8888: - /* Threated as monochrome (R1) */ - fallthrough; - case DRM_FORMAT_R1: - x1 = rect->x1; - x2 = rect->x2; - break; - case DRM_FORMAT_R2: - x1 = rect->x1 * 2; - x2 = rect->x2 * 2; - break; - } - - for (int y = rect->y1; y < rect->y2; y += ST7571_PAGE_HEIGHT) { - for (int x = x1; x < x2; x++) - row[x] = st7571_transform_xy(st7571->hwbuf, x, y); - - st7571_set_position(st7571, rect->x1, y); - - /* TODO: Investige why we can't write multiple bytes at once */ - for (int x = x1; x < x2; x++) { - regmap_bulk_write(st7571->regmap, ST7571_DATA_MODE, row + x, 1); - - /* - * As the display supports grayscale, all pixels must be written as two bits - * even if the format is monochrome. - * - * The bit values maps to the following grayscale: - * 0 0 = White - * 0 1 = Light gray - * 1 0 = Dark gray - * 1 1 = Black - * - * For monochrome formats, write the same value twice to get - * either a black or white pixel. - */ - if (format == DRM_FORMAT_R1 || format == DRM_FORMAT_XRGB8888) - regmap_bulk_write(st7571->regmap, ST7571_DATA_MODE, row + x, 1); - } - } - - return 0; -} - -static int st7571_connector_get_modes(struct drm_connector *conn) -{ - struct st7571_device *st7571 = drm_to_st7571(conn->dev); - - return drm_connector_helper_get_modes_fixed(conn, &st7571->mode); -} - -static const struct drm_connector_helper_funcs st7571_connector_helper_funcs = { - .get_modes = st7571_connector_get_modes, -}; - -static const struct st7571_panel_format st7571_monochrome = { - .prepare_buffer = st7571_prepare_buffer_monochrome, - .update_rect = st7571_fb_update_rect_monochrome, - .mode = ST7571_COLOR_MODE_BLACKWHITE, - .formats = { - DRM_FORMAT_XRGB8888, - DRM_FORMAT_R1, - }, - .nformats = 2, -}; - -static const struct st7571_panel_format st7571_grayscale = { - .prepare_buffer = st7571_prepare_buffer_grayscale, - .update_rect = st7571_fb_update_rect_grayscale, - .mode = ST7571_COLOR_MODE_GRAY, - .formats = { - DRM_FORMAT_XRGB8888, - DRM_FORMAT_R1, - DRM_FORMAT_R2, - }, - .nformats = 3, -}; - -static const u64 st7571_primary_plane_fmtmods[] = { - DRM_FORMAT_MOD_LINEAR, - DRM_FORMAT_MOD_INVALID -}; - -static int st7571_primary_plane_helper_atomic_check(struct drm_plane *plane, - struct drm_atomic_state *state) -{ - struct drm_plane_state *new_plane_state = drm_atomic_get_new_plane_state(state, plane); - struct drm_crtc *new_crtc = new_plane_state->crtc; - struct drm_crtc_state *new_crtc_state = NULL; - - if (new_crtc) - new_crtc_state = drm_atomic_get_new_crtc_state(state, new_crtc); - - return drm_atomic_helper_check_plane_state(new_plane_state, new_crtc_state, - DRM_PLANE_NO_SCALING, - DRM_PLANE_NO_SCALING, - false, false); -} - -static void st7571_primary_plane_helper_atomic_update(struct drm_plane *plane, - struct drm_atomic_state *state) -{ - struct drm_plane_state *old_plane_state = drm_atomic_get_old_plane_state(state, plane); - struct drm_plane_state *plane_state = drm_atomic_get_new_plane_state(state, plane); - struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(plane_state); - struct drm_framebuffer *fb = plane_state->fb; - struct drm_atomic_helper_damage_iter iter; - struct drm_device *dev = plane->dev; - struct drm_rect damage; - struct st7571_device *st7571 = drm_to_st7571(plane->dev); - int ret, idx; - - if (!fb) - return; /* no framebuffer; plane is disabled */ - - ret = drm_gem_fb_begin_cpu_access(fb, DMA_FROM_DEVICE); - if (ret) - return; - - if (!drm_dev_enter(dev, &idx)) - goto out_drm_gem_fb_end_cpu_access; - - drm_atomic_helper_damage_iter_init(&iter, old_plane_state, plane_state); - drm_atomic_for_each_plane_damage(&iter, &damage) { - st7571->pformat->prepare_buffer(st7571, - &shadow_plane_state->data[0], - fb, &damage, - &shadow_plane_state->fmtcnv_state); - - st7571->pformat->update_rect(fb, &damage); - } - - drm_dev_exit(idx); - -out_drm_gem_fb_end_cpu_access: - drm_gem_fb_end_cpu_access(fb, DMA_FROM_DEVICE); -} - -static void st7571_primary_plane_helper_atomic_disable(struct drm_plane *plane, - struct drm_atomic_state *state) -{ - struct drm_device *dev = plane->dev; - struct st7571_device *st7571 = drm_to_st7571(plane->dev); - int idx; - - if (!drm_dev_enter(dev, &idx)) - return; - - st7571_fb_clear_screen(st7571); - drm_dev_exit(idx); -} - -static const struct drm_plane_helper_funcs st7571_primary_plane_helper_funcs = { - DRM_GEM_SHADOW_PLANE_HELPER_FUNCS, - .atomic_check = st7571_primary_plane_helper_atomic_check, - .atomic_update = st7571_primary_plane_helper_atomic_update, - .atomic_disable = st7571_primary_plane_helper_atomic_disable, -}; - -static const struct drm_plane_funcs st7571_primary_plane_funcs = { - .update_plane = drm_atomic_helper_update_plane, - .disable_plane = drm_atomic_helper_disable_plane, - .destroy = drm_plane_cleanup, - DRM_GEM_SHADOW_PLANE_FUNCS, -}; - -/* - * CRTC - */ - -static enum drm_mode_status st7571_crtc_mode_valid(struct drm_crtc *crtc, - const struct drm_display_mode *mode) -{ - struct st7571_device *st7571 = drm_to_st7571(crtc->dev); - - return drm_crtc_helper_mode_valid_fixed(crtc, mode, &st7571->mode); -} - -static const struct drm_crtc_helper_funcs st7571_crtc_helper_funcs = { - .atomic_check = drm_crtc_helper_atomic_check, - .mode_valid = st7571_crtc_mode_valid, -}; - -static const struct drm_crtc_funcs st7571_crtc_funcs = { - .reset = drm_atomic_helper_crtc_reset, - .destroy = drm_crtc_cleanup, - .set_config = drm_atomic_helper_set_config, - .page_flip = drm_atomic_helper_page_flip, - .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state, - .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state, -}; - -/* - * Encoder - */ - -static void ssd130x_encoder_atomic_enable(struct drm_encoder *encoder, - struct drm_atomic_state *state) -{ - struct drm_device *drm = encoder->dev; - struct st7571_device *st7571 = drm_to_st7571(drm); - u8 command = ST7571_DISPLAY_ON; - int ret; - - ret = st7571->pdata->init(st7571); - if (ret) - return; - - st7571_send_command_list(st7571, &command, 1); -} - -static void ssd130x_encoder_atomic_disable(struct drm_encoder *encoder, - struct drm_atomic_state *state) -{ - struct drm_device *drm = encoder->dev; - struct st7571_device *st7571 = drm_to_st7571(drm); - u8 command = ST7571_DISPLAY_OFF; - - st7571_send_command_list(st7571, &command, 1); -} - -static const struct drm_encoder_funcs st7571_encoder_funcs = { - .destroy = drm_encoder_cleanup, - -}; - -static const struct drm_encoder_helper_funcs st7571_encoder_helper_funcs = { - .atomic_enable = ssd130x_encoder_atomic_enable, - .atomic_disable = ssd130x_encoder_atomic_disable, -}; - -/* - * Connector - */ - -static const struct drm_connector_funcs st7571_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 st7571_mode_config_funcs = { - .fb_create = drm_gem_fb_create_with_dirty, - .atomic_check = drm_atomic_helper_check, - .atomic_commit = drm_atomic_helper_commit, -}; - -static struct drm_display_mode st7571_mode(struct st7571_device *st7571) -{ - struct drm_display_mode mode = { - DRM_SIMPLE_MODE(st7571->ncols, st7571->nlines, - st7571->width_mm, st7571->height_mm), - }; - - return mode; -} - -static int st7571_mode_config_init(struct st7571_device *st7571) -{ - struct drm_device *dev = &st7571->dev; - const struct st7571_panel_constraints *constraints = &st7571->pdata->constraints; - int ret; - - ret = drmm_mode_config_init(dev); - if (ret) - return ret; - - dev->mode_config.min_width = constraints->min_ncols; - dev->mode_config.min_height = constraints->min_nlines; - dev->mode_config.max_width = constraints->max_ncols; - dev->mode_config.max_height = constraints->max_nlines; - dev->mode_config.preferred_depth = 24; - dev->mode_config.funcs = &st7571_mode_config_funcs; - - return 0; -} - -static int st7571_plane_init(struct st7571_device *st7571, - const struct st7571_panel_format *pformat) -{ - struct drm_plane *primary_plane = &st7571->primary_plane; - struct drm_device *dev = &st7571->dev; - int ret; - - ret = drm_universal_plane_init(dev, primary_plane, 0, - &st7571_primary_plane_funcs, - pformat->formats, - pformat->nformats, - st7571_primary_plane_fmtmods, - DRM_PLANE_TYPE_PRIMARY, NULL); - if (ret) - return ret; - - drm_plane_helper_add(primary_plane, &st7571_primary_plane_helper_funcs); - drm_plane_enable_fb_damage_clips(primary_plane); - - return 0; -} - -static int st7571_crtc_init(struct st7571_device *st7571) -{ - struct drm_plane *primary_plane = &st7571->primary_plane; - struct drm_crtc *crtc = &st7571->crtc; - struct drm_device *dev = &st7571->dev; - int ret; - - ret = drm_crtc_init_with_planes(dev, crtc, primary_plane, NULL, - &st7571_crtc_funcs, NULL); - if (ret) - return ret; - - drm_crtc_helper_add(crtc, &st7571_crtc_helper_funcs); - - return 0; -} - -static int st7571_encoder_init(struct st7571_device *st7571) -{ - struct drm_encoder *encoder = &st7571->encoder; - struct drm_crtc *crtc = &st7571->crtc; - struct drm_device *dev = &st7571->dev; - int ret; - - ret = drm_encoder_init(dev, encoder, &st7571_encoder_funcs, DRM_MODE_ENCODER_NONE, NULL); - if (ret) - return ret; - - drm_encoder_helper_add(encoder, &st7571_encoder_helper_funcs); - - encoder->possible_crtcs = drm_crtc_mask(crtc); - - return 0; -} - -static int st7571_connector_init(struct st7571_device *st7571) -{ - struct drm_connector *connector = &st7571->connector; - struct drm_encoder *encoder = &st7571->encoder; - struct drm_device *dev = &st7571->dev; - int ret; - - ret = drm_connector_init(dev, connector, &st7571_connector_funcs, - DRM_MODE_CONNECTOR_Unknown); - if (ret) - return ret; - - drm_connector_helper_add(connector, &st7571_connector_helper_funcs); - - return drm_connector_attach_encoder(connector, encoder); -} - -DEFINE_DRM_GEM_FOPS(st7571_fops); - -static const struct drm_driver st7571_driver = { - .driver_features = DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, - - .name = DRIVER_NAME, - .desc = DRIVER_DESC, - .major = DRIVER_MAJOR, - .minor = DRIVER_MINOR, - - .fops = &st7571_fops, - DRM_GEM_SHMEM_DRIVER_OPS, - DRM_FBDEV_SHMEM_DRIVER_OPS, -}; - -static const struct regmap_bus st7571_regmap_bus = { - .read = st7571_regmap_read, - .write = st7571_regmap_write, -}; - -static const struct regmap_config st7571_regmap_config = { - .reg_bits = 8, - .val_bits = 8, - .use_single_write = true, -}; - -static int st7571_validate_parameters(struct st7571_device *st7571) -{ - struct device *dev = st7571->dev.dev; - const struct st7571_panel_constraints *constraints = &st7571->pdata->constraints; - - if (st7571->width_mm == 0) { - dev_err(dev, "Invalid panel width\n"); - return -EINVAL; - } - - if (st7571->height_mm == 0) { - dev_err(dev, "Invalid panel height\n"); - return -EINVAL; - } - - if (st7571->nlines < constraints->min_nlines || - st7571->nlines > constraints->max_nlines) { - dev_err(dev, "Invalid timing configuration.\n"); - return -EINVAL; - } - - if (st7571->startline + st7571->nlines > constraints->max_nlines) { - dev_err(dev, "Invalid timing configuration.\n"); - return -EINVAL; - } - - if (st7571->ncols < constraints->min_ncols || - st7571->ncols > constraints->max_ncols) { - dev_err(dev, "Invalid timing configuration.\n"); - return -EINVAL; - } - - if (st7571->grayscale && !constraints->support_grayscale) { - dev_err(dev, "Grayscale not supported\n"); - return -EINVAL; - } - - return 0; -} - -static int st7571_parse_dt(struct st7571_device *st7571) -{ - struct device *dev = &st7571->client->dev; - struct device_node *np = dev->of_node; - struct display_timing dt; - int ret; - - ret = of_get_display_timing(np, "panel-timing", &dt); - if (ret) { - dev_err(dev, "Failed to get display timing from DT\n"); - return ret; - } - - of_property_read_u32(np, "width-mm", &st7571->width_mm); - of_property_read_u32(np, "height-mm", &st7571->height_mm); - st7571->grayscale = of_property_read_bool(np, "sitronix,grayscale"); - - if (st7571->grayscale) { - st7571->pformat = &st7571_grayscale; - st7571->bpp = 2; - } else { - st7571->pformat = &st7571_monochrome; - st7571->bpp = 1; - } - - st7571->startline = dt.vfront_porch.typ; - st7571->nlines = dt.vactive.typ; - st7571->ncols = dt.hactive.typ; - - st7571->reset = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH); - if (IS_ERR(st7571->reset)) - return PTR_ERR(st7571->reset); - - return 0; -} - -static void st7571_reset(struct st7571_device *st7571) -{ - gpiod_set_value_cansleep(st7571->reset, 1); - fsleep(20); - gpiod_set_value_cansleep(st7571->reset, 0); -} - -static int st7571_lcd_init(struct st7571_device *st7571) -{ - /* - * Most of the initialization sequence is taken directly from the - * referential initial code in the ST7571 datasheet. - */ - u8 commands[] = { - ST7571_DISPLAY_OFF, - - ST7571_SET_MODE_MSB, - ST7571_SET_MODE_LSB(0x2e), - - ST7571_SET_SEG_SCAN_DIR(0), - ST7571_SET_COM_SCAN_DIR(1), - - ST7571_SET_COM0_MSB, - ST7571_SET_COM0_LSB(0x00), - - ST7571_SET_START_LINE_MSB, - ST7571_SET_START_LINE_LSB(st7571->startline), - - ST7571_OSC_ON, - ST7571_SET_REGULATOR_REG(5), - ST7571_SET_CONTRAST_MSB, - ST7571_SET_CONTRAST_LSB(0x33), - ST7571_SET_LCD_BIAS(0x04), - ST7571_SET_DISPLAY_DUTY_MSB, - ST7571_SET_DISPLAY_DUTY_LSB(st7571->nlines), - - ST7571_SET_POWER(0x4), /* Power Control, VC: ON, VR: OFF, VF: OFF */ - ST7571_SET_POWER(0x6), /* Power Control, VC: ON, VR: ON, VF: OFF */ - ST7571_SET_POWER(0x7), /* Power Control, VC: ON, VR: ON, VF: ON */ - - ST7571_COMMAND_SET_3, - ST7571_SET_COLOR_MODE(st7571->pformat->mode), - ST7571_COMMAND_SET_NORMAL, - - ST7571_SET_REVERSE(0), - ST7571_SET_ENTIRE_DISPLAY_ON(0), - }; - - /* Perform a reset before initializing the controller */ - st7571_reset(st7571); - - return st7571_send_command_list(st7571, commands, ARRAY_SIZE(commands)); -} - -static int st7571_probe(struct i2c_client *client) -{ - struct st7571_device *st7571; - struct drm_device *dev; - int ret; - - st7571 = devm_drm_dev_alloc(&client->dev, &st7571_driver, - struct st7571_device, dev); - if (IS_ERR(st7571)) - return PTR_ERR(st7571); - - dev = &st7571->dev; - st7571->client = client; - i2c_set_clientdata(client, st7571); - st7571->pdata = device_get_match_data(&client->dev); - - ret = st7571_parse_dt(st7571); - if (ret) - return ret; - - ret = st7571_validate_parameters(st7571); - if (ret) - return ret; - - st7571->mode = st7571_mode(st7571); - - /* - * The hardware design could make it hard to detect a NAK on the I2C bus. - * If the adapter does not support protocol mangling do - * not set the I2C_M_IGNORE_NAK flag at the expense * of possible - * cruft in the logs. - */ - if (i2c_check_functionality(client->adapter, I2C_FUNC_PROTOCOL_MANGLING)) - st7571->ignore_nak = true; - - st7571->regmap = devm_regmap_init(&client->dev, &st7571_regmap_bus, - client, &st7571_regmap_config); - if (IS_ERR(st7571->regmap)) { - return dev_err_probe(&client->dev, PTR_ERR(st7571->regmap), - "Failed to initialize regmap\n"); - } - - st7571->hwbuf = devm_kzalloc(&client->dev, - (st7571->nlines * st7571->ncols * st7571->bpp) / 8, - GFP_KERNEL); - if (IS_ERR(st7571->hwbuf)) - return dev_err_probe(&client->dev, PTR_ERR(st7571->hwbuf), - "Failed to allocate intermediate buffer\n"); - - st7571->row = devm_kzalloc(&client->dev, - (st7571->ncols * st7571->bpp), - GFP_KERNEL); - if (IS_ERR(st7571->row)) - return dev_err_probe(&client->dev, PTR_ERR(st7571->row), - "Failed to allocate row buffer\n"); - - ret = st7571_mode_config_init(st7571); - if (ret) - return dev_err_probe(&client->dev, ret, - "Failed to initialize mode config\n"); - - ret = st7571_plane_init(st7571, st7571->pformat); - if (ret) - return dev_err_probe(&client->dev, ret, - "Failed to initialize primary plane\n"); - - ret = st7571_crtc_init(st7571); - if (ret < 0) - return dev_err_probe(&client->dev, ret, - "Failed to initialize CRTC\n"); - - ret = st7571_encoder_init(st7571); - if (ret < 0) - return dev_err_probe(&client->dev, ret, - "Failed to initialize encoder\n"); - - ret = st7571_connector_init(st7571); - if (ret < 0) - return dev_err_probe(&client->dev, ret, - "Failed to initialize connector\n"); - - drm_mode_config_reset(dev); - - ret = drm_dev_register(dev, 0); - if (ret) - return dev_err_probe(&client->dev, ret, - "Failed to register DRM device\n"); - - drm_client_setup(dev, NULL); - return 0; -} - -static void st7571_remove(struct i2c_client *client) -{ - struct st7571_device *st7571 = i2c_get_clientdata(client); - - drm_dev_unplug(&st7571->dev); -} - -struct st7571_panel_data st7571_config = { - .init = st7571_lcd_init, - .constraints = { - .min_nlines = 1, - .max_nlines = 128, - .min_ncols = 128, - .max_ncols = 128, - .support_grayscale = true, - }, -}; - -static const struct of_device_id st7571_of_match[] = { - { .compatible = "sitronix,st7571", .data = &st7571_config }, - {}, -}; -MODULE_DEVICE_TABLE(of, st7571_of_match); - -static const struct i2c_device_id st7571_id[] = { - { "st7571", 0 }, - { } -}; -MODULE_DEVICE_TABLE(i2c, st7571_id); - -static struct i2c_driver st7571_i2c_driver = { - .driver = { - .name = "st7571", - .of_match_table = st7571_of_match, - }, - .probe = st7571_probe, - .remove = st7571_remove, - .id_table = st7571_id, -}; - -module_i2c_driver(st7571_i2c_driver); - -MODULE_AUTHOR("Marcus Folkesson <marcus.folkesson@gmail.com>"); -MODULE_DESCRIPTION("DRM Driver for Sitronix ST7571 LCD controller"); -MODULE_LICENSE("GPL"); |