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path: root/drivers/video/fbdev/ssd1307fb.c
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Diffstat (limited to 'drivers/video/fbdev/ssd1307fb.c')
-rw-r--r--drivers/video/fbdev/ssd1307fb.c810
1 files changed, 810 insertions, 0 deletions
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
new file mode 100644
index 000000000..eda448b7a
--- /dev/null
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -0,0 +1,810 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Driver for the Solomon SSD1307 OLED controller
+ *
+ * Copyright 2012 Free Electrons
+ */
+
+#include <linux/backlight.h>
+#include <linux/delay.h>
+#include <linux/fb.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/pwm.h>
+#include <linux/uaccess.h>
+#include <linux/regulator/consumer.h>
+
+#define SSD1307FB_DATA 0x40
+#define SSD1307FB_COMMAND 0x80
+
+#define SSD1307FB_SET_ADDRESS_MODE 0x20
+#define SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL (0x00)
+#define SSD1307FB_SET_ADDRESS_MODE_VERTICAL (0x01)
+#define SSD1307FB_SET_ADDRESS_MODE_PAGE (0x02)
+#define SSD1307FB_SET_COL_RANGE 0x21
+#define SSD1307FB_SET_PAGE_RANGE 0x22
+#define SSD1307FB_CONTRAST 0x81
+#define SSD1307FB_SET_LOOKUP_TABLE 0x91
+#define SSD1307FB_CHARGE_PUMP 0x8d
+#define SSD1307FB_SEG_REMAP_ON 0xa1
+#define SSD1307FB_DISPLAY_OFF 0xae
+#define SSD1307FB_SET_MULTIPLEX_RATIO 0xa8
+#define SSD1307FB_DISPLAY_ON 0xaf
+#define SSD1307FB_START_PAGE_ADDRESS 0xb0
+#define SSD1307FB_SET_DISPLAY_OFFSET 0xd3
+#define SSD1307FB_SET_CLOCK_FREQ 0xd5
+#define SSD1307FB_SET_AREA_COLOR_MODE 0xd8
+#define SSD1307FB_SET_PRECHARGE_PERIOD 0xd9
+#define SSD1307FB_SET_COM_PINS_CONFIG 0xda
+#define SSD1307FB_SET_VCOMH 0xdb
+
+#define MAX_CONTRAST 255
+
+#define REFRESHRATE 1
+
+static u_int refreshrate = REFRESHRATE;
+module_param(refreshrate, uint, 0);
+
+struct ssd1307fb_deviceinfo {
+ u32 default_vcomh;
+ u32 default_dclk_div;
+ u32 default_dclk_frq;
+ int need_pwm;
+ int need_chargepump;
+};
+
+struct ssd1307fb_par {
+ 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;
+ const struct ssd1307fb_deviceinfo *device_info;
+ struct i2c_client *client;
+ u32 height;
+ struct fb_info *info;
+ u8 lookup_table[4];
+ u32 page_offset;
+ u32 col_offset;
+ u32 prechargep1;
+ u32 prechargep2;
+ struct pwm_device *pwm;
+ struct gpio_desc *reset;
+ struct regulator *vbat_reg;
+ u32 vcomh;
+ u32 width;
+};
+
+struct ssd1307fb_array {
+ u8 type;
+ u8 data[];
+};
+
+static const struct fb_fix_screeninfo ssd1307fb_fix = {
+ .id = "Solomon SSD1307",
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_MONO10,
+ .xpanstep = 0,
+ .ypanstep = 0,
+ .ywrapstep = 0,
+ .accel = FB_ACCEL_NONE,
+};
+
+static const struct fb_var_screeninfo ssd1307fb_var = {
+ .bits_per_pixel = 1,
+ .red = { .length = 1 },
+ .green = { .length = 1 },
+ .blue = { .length = 1 },
+};
+
+static struct ssd1307fb_array *ssd1307fb_alloc_array(u32 len, u8 type)
+{
+ struct ssd1307fb_array *array;
+
+ array = kzalloc(sizeof(struct ssd1307fb_array) + len, GFP_KERNEL);
+ if (!array)
+ return NULL;
+
+ array->type = type;
+
+ return array;
+}
+
+static int ssd1307fb_write_array(struct i2c_client *client,
+ struct ssd1307fb_array *array, u32 len)
+{
+ int ret;
+
+ len += sizeof(struct ssd1307fb_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 ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd)
+{
+ struct ssd1307fb_array *array;
+ int ret;
+
+ array = ssd1307fb_alloc_array(1, SSD1307FB_COMMAND);
+ if (!array)
+ return -ENOMEM;
+
+ array->data[0] = cmd;
+
+ ret = ssd1307fb_write_array(client, array, 1);
+ kfree(array);
+
+ return ret;
+}
+
+static void ssd1307fb_update_display(struct ssd1307fb_par *par)
+{
+ struct ssd1307fb_array *array;
+ u8 *vmem = par->info->screen_buffer;
+ unsigned int line_length = par->info->fix.line_length;
+ unsigned int pages = DIV_ROUND_UP(par->height, 8);
+ int i, j, k;
+
+ array = ssd1307fb_alloc_array(par->width * pages, SSD1307FB_DATA);
+ if (!array)
+ return;
+
+ /*
+ * 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
+ */
+
+ for (i = 0; i < pages; i++) {
+ for (j = 0; j < par->width; j++) {
+ int m = 8;
+ u32 array_idx = i * par->width + j;
+ array->data[array_idx] = 0;
+ /* Last page may be partial */
+ if (i + 1 == pages && par->height % 8)
+ m = par->height % 8;
+ for (k = 0; k < m; k++) {
+ u8 byte = vmem[(8 * i + k) * line_length +
+ j / 8];
+ u8 bit = (byte >> (j % 8)) & 1;
+ array->data[array_idx] |= bit << k;
+ }
+ }
+ }
+
+ ssd1307fb_write_array(par->client, array, par->width * pages);
+ kfree(array);
+}
+
+
+static ssize_t ssd1307fb_write(struct fb_info *info, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ struct ssd1307fb_par *par = info->par;
+ unsigned long total_size;
+ unsigned long p = *ppos;
+ void *dst;
+
+ total_size = info->fix.smem_len;
+
+ if (p > total_size)
+ return -EINVAL;
+
+ if (count + p > total_size)
+ count = total_size - p;
+
+ if (!count)
+ return -EINVAL;
+
+ dst = info->screen_buffer + p;
+
+ if (copy_from_user(dst, buf, count))
+ return -EFAULT;
+
+ ssd1307fb_update_display(par);
+
+ *ppos += count;
+
+ return count;
+}
+
+static int ssd1307fb_blank(int blank_mode, struct fb_info *info)
+{
+ struct ssd1307fb_par *par = info->par;
+
+ if (blank_mode != FB_BLANK_UNBLANK)
+ return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
+ else
+ return ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
+}
+
+static void ssd1307fb_fillrect(struct fb_info *info, const struct fb_fillrect *rect)
+{
+ struct ssd1307fb_par *par = info->par;
+ sys_fillrect(info, rect);
+ ssd1307fb_update_display(par);
+}
+
+static void ssd1307fb_copyarea(struct fb_info *info, const struct fb_copyarea *area)
+{
+ struct ssd1307fb_par *par = info->par;
+ sys_copyarea(info, area);
+ ssd1307fb_update_display(par);
+}
+
+static void ssd1307fb_imageblit(struct fb_info *info, const struct fb_image *image)
+{
+ struct ssd1307fb_par *par = info->par;
+ sys_imageblit(info, image);
+ ssd1307fb_update_display(par);
+}
+
+static const struct fb_ops ssd1307fb_ops = {
+ .owner = THIS_MODULE,
+ .fb_read = fb_sys_read,
+ .fb_write = ssd1307fb_write,
+ .fb_blank = ssd1307fb_blank,
+ .fb_fillrect = ssd1307fb_fillrect,
+ .fb_copyarea = ssd1307fb_copyarea,
+ .fb_imageblit = ssd1307fb_imageblit,
+};
+
+static void ssd1307fb_deferred_io(struct fb_info *info,
+ struct list_head *pagelist)
+{
+ ssd1307fb_update_display(info->par);
+}
+
+static int ssd1307fb_init(struct ssd1307fb_par *par)
+{
+ struct pwm_state pwmstate;
+ int ret;
+ u32 precharge, dclk, com_invdir, compins;
+
+ if (par->device_info->need_pwm) {
+ par->pwm = pwm_get(&par->client->dev, NULL);
+ if (IS_ERR(par->pwm)) {
+ dev_err(&par->client->dev, "Could not get PWM from device tree!\n");
+ return PTR_ERR(par->pwm);
+ }
+
+ pwm_init_state(par->pwm, &pwmstate);
+ pwm_set_relative_duty_cycle(&pwmstate, 50, 100);
+ pwm_apply_state(par->pwm, &pwmstate);
+
+ /* Enable the PWM */
+ pwm_enable(par->pwm);
+
+ dev_dbg(&par->client->dev, "Using PWM%d with a %lluns period.\n",
+ par->pwm->pwm, pwm_get_period(par->pwm));
+ }
+
+ /* Set initial contrast */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->contrast);
+ if (ret < 0)
+ return ret;
+
+ /* Set segment re-map */
+ if (par->seg_remap) {
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Set COM direction */
+ com_invdir = 0xc0 | par->com_invdir << 3;
+ ret = ssd1307fb_write_cmd(par->client, com_invdir);
+ if (ret < 0)
+ return ret;
+
+ /* Set multiplex ratio value */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->height - 1);
+ if (ret < 0)
+ return ret;
+
+ /* set display offset value */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_DISPLAY_OFFSET);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->com_offset);
+ if (ret < 0)
+ return ret;
+
+ /* Set clock frequency */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ);
+ if (ret < 0)
+ return ret;
+
+ dclk = ((par->dclk_div - 1) & 0xf) | (par->dclk_frq & 0xf) << 4;
+ ret = ssd1307fb_write_cmd(par->client, dclk);
+ if (ret < 0)
+ return ret;
+
+ /* Set Set Area Color Mode ON/OFF & Low Power Display Mode */
+ if (par->area_color_enable || par->low_power) {
+ u32 mode;
+
+ ret = ssd1307fb_write_cmd(par->client,
+ SSD1307FB_SET_AREA_COLOR_MODE);
+ if (ret < 0)
+ return ret;
+
+ mode = (par->area_color_enable ? 0x30 : 0) |
+ (par->low_power ? 5 : 0);
+ ret = ssd1307fb_write_cmd(par->client, mode);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Set precharge period in number of ticks from the internal clock */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PRECHARGE_PERIOD);
+ if (ret < 0)
+ return ret;
+
+ precharge = (par->prechargep1 & 0xf) | (par->prechargep2 & 0xf) << 4;
+ ret = ssd1307fb_write_cmd(par->client, precharge);
+ if (ret < 0)
+ return ret;
+
+ /* Set COM pins configuration */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
+ if (ret < 0)
+ return ret;
+
+ compins = 0x02 | !par->com_seq << 4 | par->com_lrremap << 5;
+ ret = ssd1307fb_write_cmd(par->client, compins);
+ if (ret < 0)
+ return ret;
+
+ /* Set VCOMH */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->vcomh);
+ if (ret < 0)
+ return ret;
+
+ /* Turn on the DC-DC Charge Pump */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client,
+ BIT(4) | (par->device_info->need_chargepump ? BIT(2) : 0));
+ if (ret < 0)
+ return ret;
+
+ /* Set lookup table */
+ if (par->lookup_table_set) {
+ int i;
+
+ ret = ssd1307fb_write_cmd(par->client,
+ SSD1307FB_SET_LOOKUP_TABLE);
+ if (ret < 0)
+ return ret;
+
+ for (i = 0; i < ARRAY_SIZE(par->lookup_table); ++i) {
+ u8 val = par->lookup_table[i];
+
+ if (val < 31 || val > 63)
+ dev_warn(&par->client->dev,
+ "lookup table index %d value out of range 31 <= %d <= 63\n",
+ i, val);
+ ret = ssd1307fb_write_cmd(par->client, val);
+ if (ret < 0)
+ return ret;
+ }
+ }
+
+ /* Switch to horizontal addressing mode */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client,
+ SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL);
+ if (ret < 0)
+ return ret;
+
+ /* Set column range */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->col_offset);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->col_offset + par->width - 1);
+ if (ret < 0)
+ return ret;
+
+ /* Set page range */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, par->page_offset);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client,
+ par->page_offset +
+ DIV_ROUND_UP(par->height, 8) - 1);
+ if (ret < 0)
+ return ret;
+
+ /* Clear the screen */
+ ssd1307fb_update_display(par);
+
+ /* Turn on the display */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssd1307fb_update_bl(struct backlight_device *bdev)
+{
+ struct ssd1307fb_par *par = bl_get_data(bdev);
+ int ret;
+ int brightness = bdev->props.brightness;
+
+ par->contrast = brightness;
+
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
+ if (ret < 0)
+ return ret;
+ ret = ssd1307fb_write_cmd(par->client, par->contrast);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+static int ssd1307fb_get_brightness(struct backlight_device *bdev)
+{
+ struct ssd1307fb_par *par = bl_get_data(bdev);
+
+ return par->contrast;
+}
+
+static int ssd1307fb_check_fb(struct backlight_device *bdev,
+ struct fb_info *info)
+{
+ return (info->bl_dev == bdev);
+}
+
+static const struct backlight_ops ssd1307fb_bl_ops = {
+ .options = BL_CORE_SUSPENDRESUME,
+ .update_status = ssd1307fb_update_bl,
+ .get_brightness = ssd1307fb_get_brightness,
+ .check_fb = ssd1307fb_check_fb,
+};
+
+static struct ssd1307fb_deviceinfo ssd1307fb_ssd1305_deviceinfo = {
+ .default_vcomh = 0x34,
+ .default_dclk_div = 1,
+ .default_dclk_frq = 7,
+};
+
+static struct ssd1307fb_deviceinfo ssd1307fb_ssd1306_deviceinfo = {
+ .default_vcomh = 0x20,
+ .default_dclk_div = 1,
+ .default_dclk_frq = 8,
+ .need_chargepump = 1,
+};
+
+static struct ssd1307fb_deviceinfo ssd1307fb_ssd1307_deviceinfo = {
+ .default_vcomh = 0x20,
+ .default_dclk_div = 2,
+ .default_dclk_frq = 12,
+ .need_pwm = 1,
+};
+
+static struct ssd1307fb_deviceinfo ssd1307fb_ssd1309_deviceinfo = {
+ .default_vcomh = 0x34,
+ .default_dclk_div = 1,
+ .default_dclk_frq = 10,
+};
+
+static const struct of_device_id ssd1307fb_of_match[] = {
+ {
+ .compatible = "solomon,ssd1305fb-i2c",
+ .data = (void *)&ssd1307fb_ssd1305_deviceinfo,
+ },
+ {
+ .compatible = "solomon,ssd1306fb-i2c",
+ .data = (void *)&ssd1307fb_ssd1306_deviceinfo,
+ },
+ {
+ .compatible = "solomon,ssd1307fb-i2c",
+ .data = (void *)&ssd1307fb_ssd1307_deviceinfo,
+ },
+ {
+ .compatible = "solomon,ssd1309fb-i2c",
+ .data = (void *)&ssd1307fb_ssd1309_deviceinfo,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ssd1307fb_of_match);
+
+static int ssd1307fb_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct backlight_device *bl;
+ char bl_name[12];
+ struct fb_info *info;
+ struct fb_deferred_io *ssd1307fb_defio;
+ u32 vmem_size;
+ struct ssd1307fb_par *par;
+ void *vmem;
+ int ret;
+
+ info = framebuffer_alloc(sizeof(struct ssd1307fb_par), dev);
+ if (!info)
+ return -ENOMEM;
+
+ par = info->par;
+ par->info = info;
+ par->client = client;
+
+ par->device_info = device_get_match_data(dev);
+
+ par->reset = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(par->reset)) {
+ dev_err(dev, "failed to get reset gpio: %ld\n",
+ PTR_ERR(par->reset));
+ ret = PTR_ERR(par->reset);
+ goto fb_alloc_error;
+ }
+
+ par->vbat_reg = devm_regulator_get_optional(dev, "vbat");
+ if (IS_ERR(par->vbat_reg)) {
+ ret = PTR_ERR(par->vbat_reg);
+ if (ret == -ENODEV) {
+ par->vbat_reg = NULL;
+ } else {
+ dev_err(dev, "failed to get VBAT regulator: %d\n", ret);
+ goto fb_alloc_error;
+ }
+ }
+
+ if (device_property_read_u32(dev, "solomon,width", &par->width))
+ par->width = 96;
+
+ if (device_property_read_u32(dev, "solomon,height", &par->height))
+ par->height = 16;
+
+ if (device_property_read_u32(dev, "solomon,page-offset", &par->page_offset))
+ par->page_offset = 1;
+
+ if (device_property_read_u32(dev, "solomon,col-offset", &par->col_offset))
+ par->col_offset = 0;
+
+ if (device_property_read_u32(dev, "solomon,com-offset", &par->com_offset))
+ par->com_offset = 0;
+
+ if (device_property_read_u32(dev, "solomon,prechargep1", &par->prechargep1))
+ par->prechargep1 = 2;
+
+ if (device_property_read_u32(dev, "solomon,prechargep2", &par->prechargep2))
+ par->prechargep2 = 2;
+
+ if (!device_property_read_u8_array(dev, "solomon,lookup-table",
+ par->lookup_table,
+ ARRAY_SIZE(par->lookup_table)))
+ par->lookup_table_set = 1;
+
+ par->seg_remap = !device_property_read_bool(dev, "solomon,segment-no-remap");
+ par->com_seq = device_property_read_bool(dev, "solomon,com-seq");
+ par->com_lrremap = device_property_read_bool(dev, "solomon,com-lrremap");
+ par->com_invdir = device_property_read_bool(dev, "solomon,com-invdir");
+ par->area_color_enable =
+ device_property_read_bool(dev, "solomon,area-color-enable");
+ par->low_power = device_property_read_bool(dev, "solomon,low-power");
+
+ par->contrast = 127;
+ par->vcomh = par->device_info->default_vcomh;
+
+ /* Setup display timing */
+ if (device_property_read_u32(dev, "solomon,dclk-div", &par->dclk_div))
+ par->dclk_div = par->device_info->default_dclk_div;
+ if (device_property_read_u32(dev, "solomon,dclk-frq", &par->dclk_frq))
+ par->dclk_frq = par->device_info->default_dclk_frq;
+
+ vmem_size = DIV_ROUND_UP(par->width, 8) * par->height;
+
+ vmem = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+ get_order(vmem_size));
+ if (!vmem) {
+ dev_err(dev, "Couldn't allocate graphical memory.\n");
+ ret = -ENOMEM;
+ goto fb_alloc_error;
+ }
+
+ ssd1307fb_defio = devm_kzalloc(dev, sizeof(*ssd1307fb_defio),
+ GFP_KERNEL);
+ if (!ssd1307fb_defio) {
+ dev_err(dev, "Couldn't allocate deferred io.\n");
+ ret = -ENOMEM;
+ goto fb_alloc_error;
+ }
+
+ ssd1307fb_defio->delay = HZ / refreshrate;
+ ssd1307fb_defio->deferred_io = ssd1307fb_deferred_io;
+
+ info->fbops = &ssd1307fb_ops;
+ info->fix = ssd1307fb_fix;
+ info->fix.line_length = DIV_ROUND_UP(par->width, 8);
+ info->fbdefio = ssd1307fb_defio;
+
+ info->var = ssd1307fb_var;
+ info->var.xres = par->width;
+ info->var.xres_virtual = par->width;
+ info->var.yres = par->height;
+ info->var.yres_virtual = par->height;
+
+ info->screen_buffer = vmem;
+ info->fix.smem_start = __pa(vmem);
+ info->fix.smem_len = vmem_size;
+
+ fb_deferred_io_init(info);
+
+ i2c_set_clientdata(client, info);
+
+ if (par->reset) {
+ /* Reset the screen */
+ gpiod_set_value_cansleep(par->reset, 1);
+ udelay(4);
+ gpiod_set_value_cansleep(par->reset, 0);
+ udelay(4);
+ }
+
+ if (par->vbat_reg) {
+ ret = regulator_enable(par->vbat_reg);
+ if (ret) {
+ dev_err(dev, "failed to enable VBAT: %d\n", ret);
+ goto reset_oled_error;
+ }
+ }
+
+ ret = ssd1307fb_init(par);
+ if (ret)
+ goto regulator_enable_error;
+
+ ret = register_framebuffer(info);
+ if (ret) {
+ dev_err(dev, "Couldn't register the framebuffer\n");
+ goto panel_init_error;
+ }
+
+ snprintf(bl_name, sizeof(bl_name), "ssd1307fb%d", info->node);
+ bl = backlight_device_register(bl_name, dev, par, &ssd1307fb_bl_ops,
+ NULL);
+ if (IS_ERR(bl)) {
+ ret = PTR_ERR(bl);
+ dev_err(dev, "unable to register backlight device: %d\n", ret);
+ goto bl_init_error;
+ }
+
+ bl->props.brightness = par->contrast;
+ bl->props.max_brightness = MAX_CONTRAST;
+ info->bl_dev = bl;
+
+ dev_info(dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
+
+ return 0;
+
+bl_init_error:
+ unregister_framebuffer(info);
+panel_init_error:
+ if (par->device_info->need_pwm) {
+ pwm_disable(par->pwm);
+ pwm_put(par->pwm);
+ }
+regulator_enable_error:
+ if (par->vbat_reg)
+ regulator_disable(par->vbat_reg);
+reset_oled_error:
+ fb_deferred_io_cleanup(info);
+fb_alloc_error:
+ framebuffer_release(info);
+ return ret;
+}
+
+static int ssd1307fb_remove(struct i2c_client *client)
+{
+ struct fb_info *info = i2c_get_clientdata(client);
+ struct ssd1307fb_par *par = info->par;
+
+ ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_OFF);
+
+ backlight_device_unregister(info->bl_dev);
+
+ unregister_framebuffer(info);
+ if (par->device_info->need_pwm) {
+ pwm_disable(par->pwm);
+ pwm_put(par->pwm);
+ }
+ if (par->vbat_reg)
+ regulator_disable(par->vbat_reg);
+ fb_deferred_io_cleanup(info);
+ __free_pages(__va(info->fix.smem_start), get_order(info->fix.smem_len));
+ framebuffer_release(info);
+
+ return 0;
+}
+
+static const struct i2c_device_id ssd1307fb_i2c_id[] = {
+ { "ssd1305fb", 0 },
+ { "ssd1306fb", 0 },
+ { "ssd1307fb", 0 },
+ { "ssd1309fb", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id);
+
+static struct i2c_driver ssd1307fb_driver = {
+ .probe_new = ssd1307fb_probe,
+ .remove = ssd1307fb_remove,
+ .id_table = ssd1307fb_i2c_id,
+ .driver = {
+ .name = "ssd1307fb",
+ .of_match_table = ssd1307fb_of_match,
+ },
+};
+
+module_i2c_driver(ssd1307fb_driver);
+
+MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controller");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
+MODULE_LICENSE("GPL");