Hi Javier,
On Mon, Feb 14, 2022 at 2:37 PM Javier Martinez Canillas javierm@redhat.com wrote:
This adds a DRM driver for SSD1305, SSD1306, SSD1307 and SSD1309 Solomon OLED display controllers.
It's only the core part of the driver and a bus specific driver is needed for each transport interface supported by the display controllers.
Signed-off-by: Javier Martinez Canillas javierm@redhat.com
--- /dev/null +++ b/drivers/gpu/drm/solomon/ssd130x.c
+static int ssd130x_update_rect(struct ssd130x_device *ssd130x, u8 *buf,
struct drm_rect *rect)+{
unsigned int x = rect->x1;unsigned int y = rect->y1;unsigned int width = drm_rect_width(rect);unsigned int height = drm_rect_height(rect);unsigned int line_length = DIV_ROUND_UP(width, 8);unsigned int pages = DIV_ROUND_UP(y % 8 + height, 8);u32 array_idx = 0;int ret, i, j, k;u8 *data_array = NULL;data_array = kcalloc(width, pages, GFP_KERNEL);if (!data_array)return -ENOMEM;/** The screen is divided in pages, each having a height of 8* pixels, and the width of the screen. When sending a byte of* data to the controller, it gives the 8 bits for the current* column. I.e, the first byte are the 8 bits of the first* column, then the 8 bits for the second column, etc.*** Representation of the screen, assuming it is 5 bits* wide. Each letter-number combination is a bit that controls* one pixel.** A0 A1 A2 A3 A4* B0 B1 B2 B3 B4* C0 C1 C2 C3 C4* D0 D1 D2 D3 D4* E0 E1 E2 E3 E4* F0 F1 F2 F3 F4* G0 G1 G2 G3 G4* H0 H1 H2 H3 H4** If you want to update this screen, you need to send 5 bytes:* (1) A0 B0 C0 D0 E0 F0 G0 H0* (2) A1 B1 C1 D1 E1 F1 G1 H1* (3) A2 B2 C2 D2 E2 F2 G2 H2* (4) A3 B3 C3 D3 E3 F3 G3 H3* (5) A4 B4 C4 D4 E4 F4 G4 H4*/ret = ssd130x_set_col_range(ssd130x, ssd130x->col_offset + x, width);if (ret < 0)goto out_free;ret = ssd130x_set_page_range(ssd130x, ssd130x->page_offset + y / 8, pages);if (ret < 0)goto out_free;for (i = y / 8; i < y / 8 + pages; i++) {int m = 8;/* Last page may be partial */if (8 * (i + 1) > ssd130x->height)m = ssd130x->height % 8;for (j = x; j < x + width; j++) {u8 data = 0;for (k = 0; k < m; k++) {u8 byte = buf[(8 * i + k) * line_length + j / 8];
As buf does not point to (0, 0), the above is not correct if rect.x1 != 0 or rect.y1 != 0. After fixing that, writing more than one text line to the console works, but I still see an issue with updates where the rectangle size and/or position are not aligned to 8 pixels horizontally. Will do more investigation, and send fixes...
u8 bit = (byte >> (j % 8)) & 1;data |= bit << k;}data_array[array_idx++] = data;}}ret = ssd130x_write_data(ssd130x, data_array, width * pages);+out_free:
kfree(data_array);return ret;+}
+static void ssd130x_clear_screen(struct ssd130x_device *ssd130x) +{
u8 *buf = NULL;struct drm_rect fullscreen = {.x1 = 0,.x2 = ssd130x->width,.y1 = 0,.y2 = ssd130x->height,};buf = kcalloc(ssd130x->width, ssd130x->height, GFP_KERNEL);
This buffer is larger than needed. Will send a fix.
if (!buf)return;ssd130x_update_rect(ssd130x, buf, &fullscreen);kfree(buf);+}
+static int ssd130x_fb_blit_rect(struct drm_framebuffer *fb, const struct dma_buf_map *map,
struct drm_rect *rect)+{
struct ssd130x_device *ssd130x = drm_to_ssd130x(fb->dev);void *vmap = map->vaddr; /* TODO: Use mapping abstraction properly */int ret = 0;u8 *buf = NULL;buf = kcalloc(fb->width, fb->height, GFP_KERNEL);
This buffer is much larger than needed. Will send a fix.
if (!buf)return -ENOMEM;drm_fb_xrgb8888_to_mono_reversed(buf, 0, vmap, fb, rect);ssd130x_update_rect(ssd130x, buf, rect);kfree(buf);return ret;+}
Gr{oetje,eeting}s,
Geert
-- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds