On 1/26/22 15:15, Javier Martinez Canillas wrote:
> On 1/26/22 15:10, Andy Shevchenko wrote:
>> On Wed, Jan 26, 2022 at 04:08:32PM +0200, Andy Shevchenko wrote:
>>> On Wed, Jan 26, 2022 at 02:46:08PM +0100, Javier Martinez Canillas wrote:
>>>> On 1/26/22 14:12, Andy Shevchenko wrote:
>>
>> ...
>>
>>>> I've just bought a SSD1306 (I2C) based one and will attempt to write a DRM
>>>> driver using drivers/staging/fbtft/fb_ssd1306.c as a reference.
>>>
>>> You should take ssd1307fb.c instead. And basically create a MIPI based driver
>>> for I2C. Then we won't go same road again for other similar devices.
>>
>> For the record it supports your device:
>>
>> static const struct i2c_device_id ssd1307fb_i2c_id[] = {
>> { "ssd1305fb", 0 },
>> { "ssd1306fb", 0 },
>> { "ssd1307fb", 0 },
>> { "ssd1309fb", 0 },
>>
>>
>
> Thanks a lot for the pointer. I was only looking at drivers/staging
> and didn't check drivers/video. I'll try to convert that one then
> once I get the display.
>
I got some time this weekend and was able to port the ssd1306 fbdev driver
to DRM [0]. I'm not that familiar with the simple display pipe helpers, so
there may be some wrong things there. But it does work and all the fbtests
from https://git.kernel.org/pub/scm/linux/kernel/git/geert/fbtest.git pass.
There are some hacks in the driver though. For example it exposes an XRGB8888
format even thought the OLED display is monochromatic and has 1 bit per pixel.
The driver then goes and converts the XRGB8888 pixels first to grayscale and
then to reverse mono. I took that idea from the repaper driver but that gives
us the multiple copies that Geert was complaining about.
Another hack is that I am just hardcoding the {width, height}_mm, but I don't
know what DPI could be used for these panels nor how I could calculate the mm.
Best regards,
Javier
[0]:
>From 5ec4b468b66022d4c48ae6bec8a68926a01a6785 Mon Sep 17 00:00:00 2001
From: Javier Martinez Canillas <javierm@xxxxxxxxxx>
Date: Sun, 30 Jan 2022 12:16:34 +0100
Subject: [RFC] drm/tiny: Add driver for Solomon SSD130X OLED displays
Add a DRM driver for SSD1305, SSD1306, SSD1307 and SSD1309 Solomon OLED
controllers that can be programmed via an I2C interface. This is a port
of the ssd1307fb driver that already supports these devices.
A Device Tree binding is not added because the DRM driver is compatible
with the existing binding for the ssd1307fb driver.
Signed-off-by: Javier Martinez Canillas <javierm@xxxxxxxxxx>
---
MAINTAINERS | 7 +
drivers/gpu/drm/tiny/Kconfig | 12 +
drivers/gpu/drm/tiny/Makefile | 1 +
drivers/gpu/drm/tiny/ssd130x.c | 944 +++++++++++++++++++++++++++++++++
4 files changed, 964 insertions(+)
create mode 100644 drivers/gpu/drm/tiny/ssd130x.c
diff --git a/MAINTAINERS b/MAINTAINERS
index d03ad8da1f36..87334676ce07 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6102,6 +6102,13 @@ T: git git://anongit.freedesktop.org/drm/drm-misc
F: Documentation/devicetree/bindings/display/repaper.txt
F: drivers/gpu/drm/tiny/repaper.c
+DRM DRIVER FOR SOLOMON SSD130X DISPLAYS
+M: Javier Martinez Canillas <javierm@xxxxxxxxxx>
+S: Maintained
+T: git git://anongit.freedesktop.org/drm/drm-misc
+F: Documentation/devicetree/bindings/display/solomon,ssd1307fb.yaml
+F: drivers/gpu/drm/tiny/ssd130x.c
+
DRM DRIVER FOR QEMU'S CIRRUS DEVICE
M: Dave Airlie <airlied@xxxxxxxxxx>
M: Gerd Hoffmann <kraxel@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/tiny/Kconfig b/drivers/gpu/drm/tiny/Kconfig
index 712e0004e96e..358ceb7354f5 100644
--- a/drivers/gpu/drm/tiny/Kconfig
+++ b/drivers/gpu/drm/tiny/Kconfig
@@ -157,6 +157,18 @@ config TINYDRM_REPAPER
If M is selected the module will be called repaper.
+config TINYDRM_SSD130X
+ tristate "DRM support for Solomon SSD130X OLED displays"
+ depends on DRM && OF && I2C
+ select DRM_KMS_HELPER
+ select DRM_GEM_SHMEM_HELPER
+ select BACKLIGHT_CLASS_DEVICE
+ help
+ DRM driver for the SSD1305, SSD1306, SSD1307 and SSD1309 Solomon
+ OLED controllers that can be programmed via an I2C interface.
+
+ If M is selected the module will be called ssd130x.
+
config TINYDRM_ST7586
tristate "DRM support for Sitronix ST7586 display panels"
depends on DRM && SPI
diff --git a/drivers/gpu/drm/tiny/Makefile b/drivers/gpu/drm/tiny/Makefile
index 5d5505d40e7b..93a1d70155f0 100644
--- a/drivers/gpu/drm/tiny/Makefile
+++ b/drivers/gpu/drm/tiny/Makefile
@@ -12,5 +12,6 @@ obj-$(CONFIG_TINYDRM_ILI9341) += ili9341.o
obj-$(CONFIG_TINYDRM_ILI9486) += ili9486.o
obj-$(CONFIG_TINYDRM_MI0283QT) += mi0283qt.o
obj-$(CONFIG_TINYDRM_REPAPER) += repaper.o
+obj-$(CONFIG_TINYDRM_SSD130X) += ssd130x.o
obj-$(CONFIG_TINYDRM_ST7586) += st7586.o
obj-$(CONFIG_TINYDRM_ST7735R) += st7735r.o
diff --git a/drivers/gpu/drm/tiny/ssd130x.c b/drivers/gpu/drm/tiny/ssd130x.c
new file mode 100644
index 000000000000..88d88caeb37d
--- /dev/null
+++ b/drivers/gpu/drm/tiny/ssd130x.c
@@ -0,0 +1,944 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * DRM driver for Solomon SSD130X OLED displays
+ *
+ * Copyright 2022 Red Hat Inc.
+ *
+ * Based on drivers/video/fbdev/ssd1307fb.c
+ * Copyright 2012 Free Electrons
+ *
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/pwm.h>
+#include <linux/regulator/consumer.h>
+
+#include <drm/drm_atomic_helper.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_atomic_helper.h>
+#include <drm/drm_gem_framebuffer_helper.h>
+#include <drm/drm_gem_shmem_helper.h>
+#include <drm/drm_managed.h>
+#include <drm/drm_modes.h>
+#include <drm/drm_rect.h>
+#include <drm/drm_probe_helper.h>
+#include <drm/drm_simple_kms_helper.h>
+
+#define DRIVER_NAME "ssd130x"
+#define DRIVER_DESC "DRM driver for Solomon SSD130X OLED displays"
+#define DRIVER_DATE "20220130"
+#define DRIVER_MAJOR 1
+#define DRIVER_MINOR 0
+
+#define SSD130X_DATA 0x40
+#define SSD130X_COMMAND 0x80
+
+#define SSD130X_SET_ADDRESS_MODE 0x20
+#define SSD130X_SET_ADDRESS_MODE_HORIZONTAL (0x00)
+#define SSD130X_SET_ADDRESS_MODE_VERTICAL (0x01)
+#define SSD130X_SET_ADDRESS_MODE_PAGE (0x02)
+#define SSD130X_SET_COL_RANGE 0x21
+#define SSD130X_SET_PAGE_RANGE 0x22
+#define SSD130X_CONTRAST 0x81
+#define SSD130X_SET_LOOKUP_TABLE 0x91
+#define SSD130X_CHARGE_PUMP 0x8d
+#define SSD130X_SEG_REMAP_ON 0xa1
+#define SSD130X_DISPLAY_OFF 0xae
+#define SSD130X_SET_MULTIPLEX_RATIO 0xa8
+#define SSD130X_DISPLAY_ON 0xaf
+#define SSD130X_START_PAGE_ADDRESS 0xb0
+#define SSD130X_SET_DISPLAY_OFFSET 0xd3
+#define SSD130X_SET_CLOCK_FREQ 0xd5
+#define SSD130X_SET_AREA_COLOR_MODE 0xd8
+#define SSD130X_SET_PRECHARGE_PERIOD 0xd9
+#define SSD130X_SET_COM_PINS_CONFIG 0xda
+#define SSD130X_SET_VCOMH 0xdb
+
+#define MAX_CONTRAST 255
+
+struct ssd130x_deviceinfo {
+ u32 default_vcomh;
+ u32 default_dclk_div;
+ u32 default_dclk_frq;
+ int need_pwm;
+ int need_chargepump;
+};
+
+struct ssd130x_device {
+ struct drm_device drm;
+ struct drm_simple_display_pipe pipe;
+ struct drm_display_mode mode;
+ struct drm_connector connector;
+ struct i2c_client *client;
+
+ const struct ssd130x_deviceinfo *device_info;
+
+ unsigned area_color_enable : 1;
+ unsigned com_invdir : 1;
+ unsigned com_lrremap : 1;
+ unsigned com_seq : 1;
+ unsigned lookup_table_set : 1;
+ unsigned low_power : 1;
+ unsigned seg_remap : 1;
+ u32 com_offset;
+ u32 contrast;
+ u32 dclk_div;
+ u32 dclk_frq;
+ u32 height;
+ u8 lookup_table[4];
+ u32 page_offset;
+ u32 col_offset;
+ u32 prechargep1;
+ u32 prechargep2;
+
+ struct backlight_device *bl_dev;
+ struct pwm_device *pwm;
+ struct gpio_desc *reset;
+ struct regulator *vbat_reg;
+ u32 vcomh;
+ u32 width;
+ /* Cached address ranges */
+ u8 col_start;
+ u8 col_end;
+ u8 page_start;
+ u8 page_end;
+};
+
+struct ssd130x_array {
+ u8 type;
+ u8 data[];
+};
+
+static inline struct ssd130x_device *drm_to_ssd130x(struct drm_device *drm)
+{
+ return container_of(drm, struct ssd130x_device, drm);
+}
+
+static struct ssd130x_array *ssd130x_alloc_array(u32 len, u8 type)
+{
+ struct ssd130x_array *array;
+
+ array = kzalloc(sizeof(struct ssd130x_array) + len, GFP_KERNEL);
+ if (!array)
+ return NULL;
+
+ array->type = type;
+
+ return array;
+}
+
+static int ssd130x_write_array(struct i2c_client *client,
+ struct ssd130x_array *array, u32 len)
+{
+ int ret;
+
+ len += sizeof(struct ssd130x_array);
+
+ ret = i2c_master_send(client, (u8 *)array, len);
+ if (ret != len) {
+ dev_err(&client->dev, "Couldn't send I2C command.\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static inline int ssd130x_write_cmd(struct i2c_client *client, u8 cmd)
+{
+ struct ssd130x_array *array;
+ int ret;
+
+ array = ssd130x_alloc_array(1, SSD130X_COMMAND);
+ if (!array)
+ return -ENOMEM;
+
+ array->data[0] = cmd;
+
+ ret = ssd130x_write_array(client, array, 1);
+ kfree(array);
+
+ return ret;
+}
+
+static int ssd130x_set_col_range(struct ssd130x_device *ssd130x,
+ u8 col_start, u8 cols)
+{
+ u8 col_end = col_start + cols - 1;
+ int ret;
+
+ if (col_start == ssd130x->col_start && col_end == ssd130x->col_end)
+ return 0;
+
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_COL_RANGE);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, col_start);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, col_end);
+ if (ret < 0)
+ return ret;
+
+ ssd130x->col_start = col_start;
+ ssd130x->col_end = col_end;
+ return 0;
+}
+
+static int ssd130x_set_page_range(struct ssd130x_device *ssd130x,
+ u8 page_start, u8 pages)
+{
+ u8 page_end = page_start + pages - 1;
+ int ret;
+
+ if (page_start == ssd130x->page_start && page_end == ssd130x->page_end)
+ return 0;
+
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_PAGE_RANGE);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, page_start);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, page_end);
+ if (ret < 0)
+ return ret;
+
+ ssd130x->page_start = page_start;
+ ssd130x->page_end = page_end;
+ return 0;
+}
+
+static int ssd130x_update_display(struct ssd130x_device *ssd130x, u8 *buf,
+ u32 width, u32 height)
+{
+ struct ssd130x_array *array;
+ unsigned int line_length = DIV_ROUND_UP(width, 8);
+ unsigned int pages = DIV_ROUND_UP(height, 8);
+ u32 array_idx = 0;
+ int ret, i, j, k;
+
+ array = ssd130x_alloc_array(width * pages, SSD130X_DATA);
+ if (!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, width);
+ if (ret < 0)
+ goto out_free;
+
+ ret = ssd130x_set_page_range(ssd130x, ssd130x->page_offset / 8, pages);
+ if (ret < 0)
+ goto out_free;
+
+ for (i = 0; i < pages; i++) {
+ int m = 8;
+
+ /* Last page may be partial */
+ if (8 * (i + 1) > ssd130x->height)
+ m = ssd130x->height % 8;
+ for (j = 0; j < width; j++) {
+ u8 data = 0;
+
+ for (k = 0; k < m; k++) {
+ u8 byte = buf[(8 * i + k) * line_length +
+ j / 8];
+ u8 bit = (byte >> (j % 8)) & 1;
+
+ data |= bit << k;
+ }
+ array->data[array_idx++] = data;
+ }
+ }
+
+ ret = ssd130x_write_array(ssd130x->client, array, width * pages);
+
+out_free:
+ kfree(array);
+ return ret;
+}
+
+static void ssd130x_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 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 idx, ret = 0;
+ u8 *buf = NULL;
+
+ if (!drm_dev_enter(fb->dev, &idx))
+ return -ENODEV;
+
+ buf = kmalloc_array(fb->width, fb->height, GFP_KERNEL);
+ if (!buf) {
+ ret = -ENOMEM;
+ goto out_exit;
+ }
+
+ drm_fb_xrgb8888_to_gray8(buf, 0, vmap, fb, rect);
+
+ ssd130x_gray8_to_mono_reversed(buf, fb->width, fb->height);
+
+ ssd130x_update_display(ssd130x, buf, fb->width, fb->height);
+
+ kfree(buf);
+out_exit:
+ drm_dev_exit(idx);
+
+ return ret;
+}
+
+static void ssd130x_display_pipe_enable(struct drm_simple_display_pipe *pipe,
+ struct drm_crtc_state *crtc_state,
+ struct drm_plane_state *plane_state)
+{
+ struct ssd130x_device *ssd130x = drm_to_ssd130x(pipe->crtc.dev);
+ int idx;
+
+ if (!drm_dev_enter(pipe->crtc.dev, &idx))
+ return;
+
+ backlight_enable(ssd130x->bl_dev);
+
+ ssd130x_write_cmd(ssd130x->client, SSD130X_DISPLAY_ON);
+}
+
+static void ssd130x_display_pipe_disable(struct drm_simple_display_pipe *pipe)
+{
+ struct ssd130x_device *ssd130x = drm_to_ssd130x(pipe->crtc.dev);
+
+ ssd130x_write_cmd(ssd130x->client, SSD130X_DISPLAY_OFF);
+
+ backlight_disable(ssd130x->bl_dev);
+}
+
+static void ssd130x_display_pipe_update(struct drm_simple_display_pipe *pipe,
+ struct drm_plane_state *old_plane_state)
+{
+ struct drm_plane_state *state = pipe->plane.state;
+ struct drm_shadow_plane_state *shadow_plane_state = to_drm_shadow_plane_state(state);
+ struct drm_rect rect;
+
+ if (!pipe->crtc.state->active)
+ return;
+
+ if (drm_atomic_helper_damage_merged(old_plane_state, state, &rect))
+ ssd130x_fb_blit_rect(state->fb, &shadow_plane_state->data[0], &rect);
+}
+
+static const struct drm_simple_display_pipe_funcs ssd130x_pipe_funcs = {
+ .enable = ssd130x_display_pipe_enable,
+ .disable = ssd130x_display_pipe_disable,
+ .update = ssd130x_display_pipe_update,
+ DRM_GEM_SIMPLE_DISPLAY_PIPE_SHADOW_PLANE_FUNCS,
+};
+
+static int ssd130x_connector_get_modes(struct drm_connector *connector)
+{
+ struct ssd130x_device *ssd130x = drm_to_ssd130x(connector->dev);
+ struct drm_display_mode *mode;
+
+ mode = drm_mode_duplicate(connector->dev, &ssd130x->mode);
+ if (!mode) {
+ DRM_ERROR("Failed to duplicate mode\n");
+ return 0;
+ }
+
+ connector->display_info.width_mm = mode->width_mm;
+ connector->display_info.height_mm = mode->height_mm;
+ connector->display_info.bpc = 32;
+
+ drm_mode_set_name(mode);
+ mode->type |= DRM_MODE_TYPE_PREFERRED;
+ drm_mode_probed_add(connector, mode);
+
+ return 1;
+}
+
+static const struct drm_connector_helper_funcs ssd130x_connector_helper_funcs = {
+ .get_modes = ssd130x_connector_get_modes,
+};
+
+static const struct drm_connector_funcs ssd130x_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 ssd130x_mode_config_funcs = {
+ .fb_create = drm_gem_fb_create_with_dirty,
+ .atomic_check = drm_atomic_helper_check,
+ .atomic_commit = drm_atomic_helper_commit,
+};
+
+static const uint32_t ssd130x_formats[] = {
+ DRM_FORMAT_XRGB8888,
+};
+
+DEFINE_DRM_GEM_FOPS(ssd130x_fops);
+
+static const struct drm_driver ssd130x_drm_driver = {
+ DRM_GEM_SHMEM_DRIVER_OPS,
+ .name = DRIVER_NAME,
+ .desc = DRIVER_DESC,
+ .date = DRIVER_DATE,
+ .major = DRIVER_MAJOR,
+ .minor = DRIVER_MINOR,
+ .driver_features = DRIVER_ATOMIC | DRIVER_GEM | DRIVER_MODESET,
+ .fops = &ssd130x_fops,
+};
+
+static int ssd130x_pwm_enable(struct ssd130x_device *ssd130x)
+{
+ struct pwm_state pwmstate;
+
+ ssd130x->pwm = pwm_get(&ssd130x->client->dev, NULL);
+ if (IS_ERR(ssd130x->pwm)) {
+ dev_err(&ssd130x->client->dev, "Could not get PWM from device tree!\n");
+ return PTR_ERR(ssd130x->pwm);
+ }
+
+ pwm_init_state(ssd130x->pwm, &pwmstate);
+ pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
+ pwm_apply_state(ssd130x->pwm, &pwmstate);
+
+ /* Enable the PWM */
+ pwm_enable(ssd130x->pwm);
+
+ dev_dbg(&ssd130x->client->dev, "Using PWM%d with a %lluns period.\n",
+ ssd130x->pwm->pwm, pwm_get_period(ssd130x->pwm));
+
+ return 0;
+}
+
+static int ssd130x_init(struct ssd130x_device *ssd130x)
+{
+ u32 precharge, dclk, com_invdir, compins;
+ int ret;
+
+ /* Set initial contrast */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_CONTRAST);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, ssd130x->contrast);
+ if (ret < 0)
+ return ret;
+
+ /* Set segment re-map */
+ if (ssd130x->seg_remap) {
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SEG_REMAP_ON);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Set COM direction */
+ com_invdir = 0xc0 | ssd130x->com_invdir << 3;
+ ret = ssd130x_write_cmd(ssd130x->client, com_invdir);
+ if (ret < 0)
+ return ret;
+
+ /* Set multiplex ratio value */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_MULTIPLEX_RATIO);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, ssd130x->height - 1);
+ if (ret < 0)
+ return ret;
+
+ /* set display offset value */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_DISPLAY_OFFSET);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, ssd130x->com_offset);
+ if (ret < 0)
+ return ret;
+
+ /* Set clock frequency */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_CLOCK_FREQ);
+ if (ret < 0)
+ return ret;
+
+ dclk = ((ssd130x->dclk_div - 1) & 0xf) | (ssd130x->dclk_frq & 0xf) << 4;
+ ret = ssd130x_write_cmd(ssd130x->client, dclk);
+ if (ret < 0)
+ return ret;
+
+ /* Set Area Color Mode ON/OFF & Low Power Display Mode */
+ if (ssd130x->area_color_enable || ssd130x->low_power) {
+ u32 mode;
+
+ ret = ssd130x_write_cmd(ssd130x->client,
+ SSD130X_SET_AREA_COLOR_MODE);
+ if (ret < 0)
+ return ret;
+
+ mode = (ssd130x->area_color_enable ? 0x30 : 0) |
+ (ssd130x->low_power ? 5 : 0);
+ ret = ssd130x_write_cmd(ssd130x->client, mode);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Set precharge period in number of ticks from the internal clock */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_PRECHARGE_PERIOD);
+ if (ret < 0)
+ return ret;
+
+ precharge = (ssd130x->prechargep1 & 0xf) | (ssd130x->prechargep2 & 0xf) << 4;
+ ret = ssd130x_write_cmd(ssd130x->client, precharge);
+ if (ret < 0)
+ return ret;
+
+ /* Set COM pins configuration */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_COM_PINS_CONFIG);
+ if (ret < 0)
+ return ret;
+
+ compins = 0x02 | !ssd130x->com_seq << 4 | ssd130x->com_lrremap << 5;
+ ret = ssd130x_write_cmd(ssd130x->client, compins);
+ if (ret < 0)
+ return ret;
+
+ /* Set VCOMH */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_VCOMH);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, ssd130x->vcomh);
+ if (ret < 0)
+ return ret;
+
+ /* Turn on the DC-DC Charge Pump */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_CHARGE_PUMP);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client,
+ BIT(4) | (ssd130x->device_info->need_chargepump ? BIT(2) : 0));
+ if (ret < 0)
+ return ret;
+
+ /* Set lookup table */
+ if (ssd130x->lookup_table_set) {
+ int i;
+
+ ret = ssd130x_write_cmd(ssd130x->client,
+ SSD130X_SET_LOOKUP_TABLE);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(ssd130x->lookup_table); ++i) {
+ u8 val = ssd130x->lookup_table[i];
+
+ if (val < 31 || val > 63)
+ dev_warn(&ssd130x->client->dev,
+ "lookup table index %d value out of range 31 <= %d <= 63\n",
+ i, val);
+ ret = ssd130x_write_cmd(ssd130x->client, val);
+ if (ret < 0)
+ return ret;
+ }
+ }
+
+ /* Switch to horizontal addressing mode */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_SET_ADDRESS_MODE);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client,
+ SSD130X_SET_ADDRESS_MODE_HORIZONTAL);
+ if (ret < 0)
+ return ret;
+
+ /* Turn on the display */
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_DISPLAY_ON);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssd130x_update_bl(struct backlight_device *bdev)
+{
+ struct ssd130x_device *ssd130x = bl_get_data(bdev);
+ int brightness = bdev->props.brightness;
+ int ret;
+
+ ssd130x->contrast = brightness;
+
+ ret = ssd130x_write_cmd(ssd130x->client, SSD130X_CONTRAST);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd130x_write_cmd(ssd130x->client, ssd130x->contrast);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssd130x_get_brightness(struct backlight_device *bdev)
+{
+ struct ssd130x_device *ssd130x = bl_get_data(bdev);
+
+ return ssd130x->contrast;
+}
+
+static const struct backlight_ops ssd130xfb_bl_ops = {
+ .update_status = ssd130x_update_bl,
+ .get_brightness = ssd130x_get_brightness,
+};
+
+static void ssd130x_reset(struct ssd130x_device *ssd130x)
+{
+ /* Reset the screen */
+ gpiod_set_value_cansleep(ssd130x->reset, 1);
+ udelay(4);
+ gpiod_set_value_cansleep(ssd130x->reset, 0);
+ udelay(4);
+}
+
+static void ssd130x_parse_properties(struct ssd130x_device *ssd130x)
+{
+ struct device *dev = &ssd130x->client->dev;
+
+ if (device_property_read_u32(dev, "solomon,width", &ssd130x->width))
+ ssd130x->width = 96;
+
+ if (device_property_read_u32(dev, "solomon,height", &ssd130x->height))
+ ssd130x->height = 16;
+
+ if (device_property_read_u32(dev, "solomon,page-offset", &ssd130x->page_offset))
+ ssd130x->page_offset = 1;
+
+ if (device_property_read_u32(dev, "solomon,col-offset", &ssd130x->col_offset))
+ ssd130x->col_offset = 0;
+
+ if (device_property_read_u32(dev, "solomon,com-offset", &ssd130x->com_offset))
+ ssd130x->com_offset = 0;
+
+ if (device_property_read_u32(dev, "solomon,prechargep1", &ssd130x->prechargep1))
+ ssd130x->prechargep1 = 2;
+
+ if (device_property_read_u32(dev, "solomon,prechargep2", &ssd130x->prechargep2))
+ ssd130x->prechargep2 = 2;
+
+ if (!device_property_read_u8_array(dev, "solomon,lookup-table",
+ ssd130x->lookup_table,
+ ARRAY_SIZE(ssd130x->lookup_table)))
+ ssd130x->lookup_table_set = 1;
+
+ ssd130x->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
+ ssd130x->com_seq = device_property_read_bool(dev, "solomon,com-seq");
+ ssd130x->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
+ ssd130x->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
+ ssd130x->area_color_enable =
+ device_property_read_bool(dev, "solomon,area-color-enable");
+ ssd130x->low_power = device_property_read_bool(dev, "solomon,low-power");
+
+ ssd130x->contrast = 127;
+ ssd130x->vcomh = ssd130x->device_info->default_vcomh;
+
+ /* Setup display timing */
+ if (device_property_read_u32(dev, "solomon,dclk-div", &ssd130x->dclk_div))
+ ssd130x->dclk_div = ssd130x->device_info->default_dclk_div;
+ if (device_property_read_u32(dev, "solomon,dclk-frq", &ssd130x->dclk_frq))
+ ssd130x->dclk_frq = ssd130x->device_info->default_dclk_frq;
+}
+
+static void ssd130x_set_mode(struct ssd130x_device *ssd130x)
+{
+ struct drm_display_mode *mode = &ssd130x->mode;
+ struct drm_device *drm = &ssd130x->drm;
+
+ mode->type = DRM_MODE_TYPE_DRIVER;
+ mode->clock = 1;
+ mode->hdisplay = mode->htotal = ssd130x->width;
+ mode->hsync_start = mode->hsync_end = ssd130x->width;
+ mode->vdisplay = mode->vtotal = ssd130x->height;
+ mode->vsync_start = mode->vsync_end = ssd130x->height;
+ mode->width_mm = 27;
+ mode->height_mm = 27;
+
+ drm->mode_config.min_width = ssd130x->width;
+ drm->mode_config.max_width = ssd130x->width;
+ drm->mode_config.min_height = ssd130x->height;
+ drm->mode_config.max_height = ssd130x->height;
+ drm->mode_config.preferred_depth = 32;
+ drm->mode_config.funcs = &ssd130x_mode_config_funcs;
+}
+
+static int ssd130x_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct ssd130x_device *ssd130x;
+ struct backlight_device *bl;
+ struct drm_device *drm;
+ char bl_name[12];
+ int ret;
+
+ ssd130x = devm_drm_dev_alloc(dev, &ssd130x_drm_driver,
+ struct ssd130x_device, drm);
+ if (IS_ERR(ssd130x))
+ return PTR_ERR(ssd130x);
+
+ drm = &ssd130x->drm;
+
+ ret = drmm_mode_config_init(drm);
+ if (ret)
+ return ret;
+
+ ssd130x->client = client;
+
+ ssd130x->device_info = device_get_match_data(dev);
+
+ ssd130x_parse_properties(ssd130x);
+
+ ssd130x_set_mode(ssd130x);
+
+ ssd130x->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(ssd130x->reset)) {
+ dev_err(dev, "failed to get reset gpio: %ld\n",
+ PTR_ERR(ssd130x->reset));
+ return PTR_ERR(ssd130x->reset);
+ }
+
+ ssd130x->vbat_reg = devm_regulator_get_optional(dev, "vbat");
+ if (IS_ERR(ssd130x->vbat_reg)) {
+ ret = PTR_ERR(ssd130x->vbat_reg);
+ if (ret == -ENODEV) {
+ ssd130x->vbat_reg = NULL;
+ } else {
+ dev_err(dev, "failed to get VBAT regulator: %d\n", ret);
+ return ret;
+ }
+ }
+
+ drm_connector_helper_add(&ssd130x->connector, &ssd130x_connector_helper_funcs);
+ ret = drm_connector_init(drm, &ssd130x->connector, &ssd130x_connector_funcs,
+ DRM_MODE_CONNECTOR_Unknown);
+ if (ret)
+ return ret;
+
+ i2c_set_clientdata(client, ssd130x);
+
+ if (ssd130x->reset)
+ ssd130x_reset(ssd130x);
+
+ if (ssd130x->vbat_reg) {
+ ret = regulator_enable(ssd130x->vbat_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VBAT: %d\n", ret);
+ return ret;
+ }
+ }
+
+ ret = ssd130x_init(ssd130x);
+ if (ret)
+ goto regulator_disable;
+
+ if (ssd130x->device_info->need_pwm) {
+ ret = ssd130x_pwm_enable(ssd130x);
+ if (ret)
+ goto regulator_disable;
+ }
+
+ snprintf(bl_name, sizeof(bl_name), "ssd130x%d", drm->primary->index);
+ bl = backlight_device_register(bl_name, dev, ssd130x, &ssd130xfb_bl_ops,
+ NULL);
+ if (IS_ERR(bl)) {
+ ret = PTR_ERR(bl);
+ dev_err(dev, "unable to register backlight device: %d\n", ret);
+ goto pwm_disable;
+ }
+
+ bl->props.brightness = ssd130x->contrast;
+ bl->props.max_brightness = MAX_CONTRAST;
+ ssd130x->bl_dev = bl;
+
+ ret = drm_simple_display_pipe_init(drm, &ssd130x->pipe, &ssd130x_pipe_funcs,
+ ssd130x_formats, ARRAY_SIZE(ssd130x_formats),
+ NULL, &ssd130x->connector);
+ if (ret)
+ goto pwm_disable;
+
+ drm_plane_enable_fb_damage_clips(&ssd130x->pipe.plane);
+
+ drm_mode_config_reset(drm);
+
+ ret = drm_dev_register(drm, 0);
+ if (ret)
+ goto backlight_unregister;
+
+ drm_fbdev_generic_setup(drm, 0);
+
+ return 0;
+
+backlight_unregister:
+ backlight_device_unregister(ssd130x->bl_dev);
+pwm_disable:
+ if (ssd130x->device_info->need_pwm) {
+ pwm_disable(ssd130x->pwm);
+ pwm_put(ssd130x->pwm);
+ }
+regulator_disable:
+ if (ssd130x->vbat_reg)
+ regulator_disable(ssd130x->vbat_reg);
+ return ret;
+}
+
+static int ssd130x_remove(struct i2c_client *client)
+{
+ struct ssd130x_device *ssd130x = i2c_get_clientdata(client);
+
+ drm_dev_unplug(&ssd130x->drm);
+
+ ssd130x_write_cmd(ssd130x->client, SSD130X_DISPLAY_OFF);
+
+ backlight_device_unregister(ssd130x->bl_dev);
+
+ if (ssd130x->device_info->need_pwm) {
+ pwm_disable(ssd130x->pwm);
+ pwm_put(ssd130x->pwm);
+ }
+ if (ssd130x->vbat_reg)
+ regulator_disable(ssd130x->vbat_reg);
+
+ return 0;
+}
+
+static void ssd130x_shutdown(struct i2c_client *client)
+{
+ struct ssd130x_device *ssd130x = i2c_get_clientdata(client);
+
+ drm_atomic_helper_shutdown(&ssd130x->drm);
+}
+
+static struct ssd130x_deviceinfo ssd130x_ssd1305_deviceinfo = {
+ .default_vcomh = 0x34,
+ .default_dclk_div = 1,
+ .default_dclk_frq = 7,
+};
+
+static struct ssd130x_deviceinfo ssd130x_ssd1306_deviceinfo = {
+ .default_vcomh = 0x20,
+ .default_dclk_div = 1,
+ .default_dclk_frq = 8,
+ .need_chargepump = 1,
+};
+
+static struct ssd130x_deviceinfo ssd130x_ssd1307_deviceinfo = {
+ .default_vcomh = 0x20,
+ .default_dclk_div = 2,
+ .default_dclk_frq = 12,
+ .need_pwm = 1,
+};
+
+static struct ssd130x_deviceinfo ssd130x_ssd1309_deviceinfo = {
+ .default_vcomh = 0x34,
+ .default_dclk_div = 1,
+ .default_dclk_frq = 10,
+};
+
+static const struct of_device_id ssd130x_of_match[] = {
+ {
+ .compatible = "solomon,ssd1305fb-i2c",
+ .data = (void *)&ssd130x_ssd1305_deviceinfo,
+ },
+ {
+ .compatible = "solomon,ssd1306fb-i2c",
+ .data = (void *)&ssd130x_ssd1306_deviceinfo,
+ },
+ {
+ .compatible = "solomon,ssd1307fb-i2c",
+ .data = (void *)&ssd130x_ssd1307_deviceinfo,
+ },
+ {
+ .compatible = "solomon,ssd1309fb-i2c",
+ .data = (void *)&ssd130x_ssd1309_deviceinfo,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ssd130x_of_match);
+
+
+static struct i2c_driver ssd130x_i2c_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = ssd130x_of_match,
+ },
+ .probe_new = ssd130x_probe,
+ .remove = ssd130x_remove,
+ .shutdown = ssd130x_shutdown,
+};
+
+module_i2c_driver(ssd130x_i2c_driver);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_AUTHOR("Javier Martinez Canillas <javierm@xxxxxxxxxx>");
+MODULE_LICENSE("GPL v2");
--
2.34.1
