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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.c581
1 files changed, 581 insertions, 0 deletions
diff --git a/drivers/video/fbdev/ssd1307fb.c b/drivers/video/fbdev/ssd1307fb.c
new file mode 100644
index 000000000000..f4daa59f0a80
--- /dev/null
+++ b/drivers/video/fbdev/ssd1307fb.c
@@ -0,0 +1,581 @@
+/*
+ * Driver for the Solomon SSD1307 OLED controller
+ *
+ * Copyright 2012 Free Electrons
+ *
+ * Licensed under the GPLv2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/fb.h>
+#include <linux/uaccess.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
+#include <linux/pwm.h>
+#include <linux/delay.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_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_PRECHARGE_PERIOD 0xd9
+#define SSD1307FB_SET_COM_PINS_CONFIG 0xda
+#define SSD1307FB_SET_VCOMH 0xdb
+
+struct ssd1307fb_par;
+
+struct ssd1307fb_ops {
+ int (*init)(struct ssd1307fb_par *);
+ int (*remove)(struct ssd1307fb_par *);
+};
+
+struct ssd1307fb_par {
+ struct i2c_client *client;
+ u32 height;
+ struct fb_info *info;
+ struct ssd1307fb_ops *ops;
+ u32 page_offset;
+ struct pwm_device *pwm;
+ u32 pwm_period;
+ int reset;
+ u32 width;
+};
+
+struct ssd1307fb_array {
+ u8 type;
+ u8 data[0];
+};
+
+static 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 struct fb_var_screeninfo ssd1307fb_var = {
+ .bits_per_pixel = 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 inline int ssd1307fb_write_data(struct i2c_client *client, u8 data)
+{
+ struct ssd1307fb_array *array;
+ int ret;
+
+ array = ssd1307fb_alloc_array(1, SSD1307FB_DATA);
+ if (!array)
+ return -ENOMEM;
+
+ array->data[0] = data;
+
+ 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_base;
+ int i, j, k;
+
+ array = ssd1307fb_alloc_array(par->width * par->height / 8,
+ 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 < (par->height / 8); i++) {
+ for (j = 0; j < par->width; j++) {
+ u32 array_idx = i * par->width + j;
+ array->data[array_idx] = 0;
+ for (k = 0; k < 8; k++) {
+ u32 page_length = par->width * i;
+ u32 index = page_length + (par->width * k + j) / 8;
+ u8 byte = *(vmem + index);
+ u8 bit = byte & (1 << (j % 8));
+ bit = bit >> (j % 8);
+ array->data[array_idx] |= bit << k;
+ }
+ }
+ }
+
+ ssd1307fb_write_array(par->client, array, par->width * par->height / 8);
+ 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;
+ u8 __iomem *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 = (void __force *) (info->screen_base + p);
+
+ if (copy_from_user(dst, buf, count))
+ return -EFAULT;
+
+ ssd1307fb_update_display(par);
+
+ *ppos += count;
+
+ return count;
+}
+
+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 struct fb_ops ssd1307fb_ops = {
+ .owner = THIS_MODULE,
+ .fb_read = fb_sys_read,
+ .fb_write = ssd1307fb_write,
+ .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 struct fb_deferred_io ssd1307fb_defio = {
+ .delay = HZ,
+ .deferred_io = ssd1307fb_deferred_io,
+};
+
+static int ssd1307fb_ssd1307_init(struct ssd1307fb_par *par)
+{
+ int ret;
+
+ 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);
+ }
+
+ par->pwm_period = pwm_get_period(par->pwm);
+ /* Enable the PWM */
+ pwm_config(par->pwm, par->pwm_period / 2, par->pwm_period);
+ pwm_enable(par->pwm);
+
+ dev_dbg(&par->client->dev, "Using PWM%d with a %dns period.\n",
+ par->pwm->pwm, par->pwm_period);
+
+ /* Map column 127 of the OLED to segment 0 */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
+ if (ret < 0)
+ return ret;
+
+ /* Turn on the display */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static int ssd1307fb_ssd1307_remove(struct ssd1307fb_par *par)
+{
+ pwm_disable(par->pwm);
+ pwm_put(par->pwm);
+ return 0;
+}
+
+static struct ssd1307fb_ops ssd1307fb_ssd1307_ops = {
+ .init = ssd1307fb_ssd1307_init,
+ .remove = ssd1307fb_ssd1307_remove,
+};
+
+static int ssd1307fb_ssd1306_init(struct ssd1307fb_par *par)
+{
+ int ret;
+
+ /* Set initial contrast */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CONTRAST);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x7f);
+ if (ret < 0)
+ return ret;
+
+ /* Set COM direction */
+ ret = ssd1307fb_write_cmd(par->client, 0xc8);
+ if (ret < 0)
+ return ret;
+
+ /* Set segment re-map */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SEG_REMAP_ON);
+ if (ret < 0)
+ return ret;
+
+ /* Set multiplex ratio value */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_MULTIPLEX_RATIO);
+ 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);
+ ret = ssd1307fb_write_cmd(par->client, 0x20);
+ if (ret < 0)
+ return ret;
+
+ /* Set clock frequency */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_CLOCK_FREQ);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0xf0);
+ 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);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x22);
+ if (ret < 0)
+ return ret;
+
+ /* Set COM pins configuration */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COM_PINS_CONFIG);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x22);
+ if (ret < 0)
+ return ret;
+
+ /* Set VCOMH */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_VCOMH);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x49);
+ if (ret < 0)
+ return ret;
+
+ /* Turn on the DC-DC Charge Pump */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_CHARGE_PUMP);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x14);
+ if (ret < 0)
+ return ret;
+
+ /* Switch to horizontal addressing mode */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_ADDRESS_MODE);
+ ret = ret & ssd1307fb_write_cmd(par->client,
+ SSD1307FB_SET_ADDRESS_MODE_HORIZONTAL);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_COL_RANGE);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x0);
+ ret = ret & ssd1307fb_write_cmd(par->client, par->width - 1);
+ if (ret < 0)
+ return ret;
+
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_SET_PAGE_RANGE);
+ ret = ret & ssd1307fb_write_cmd(par->client, 0x0);
+ ret = ret & ssd1307fb_write_cmd(par->client,
+ par->page_offset + (par->height / 8) - 1);
+ if (ret < 0)
+ return ret;
+
+ /* Turn on the display */
+ ret = ssd1307fb_write_cmd(par->client, SSD1307FB_DISPLAY_ON);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static struct ssd1307fb_ops ssd1307fb_ssd1306_ops = {
+ .init = ssd1307fb_ssd1306_init,
+};
+
+static const struct of_device_id ssd1307fb_of_match[] = {
+ {
+ .compatible = "solomon,ssd1306fb-i2c",
+ .data = (void *)&ssd1307fb_ssd1306_ops,
+ },
+ {
+ .compatible = "solomon,ssd1307fb-i2c",
+ .data = (void *)&ssd1307fb_ssd1307_ops,
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ssd1307fb_of_match);
+
+static int ssd1307fb_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct fb_info *info;
+ struct device_node *node = client->dev.of_node;
+ u32 vmem_size;
+ struct ssd1307fb_par *par;
+ u8 *vmem;
+ int ret;
+
+ if (!node) {
+ dev_err(&client->dev, "No device tree data found!\n");
+ return -EINVAL;
+ }
+
+ info = framebuffer_alloc(sizeof(struct ssd1307fb_par), &client->dev);
+ if (!info) {
+ dev_err(&client->dev, "Couldn't allocate framebuffer.\n");
+ return -ENOMEM;
+ }
+
+ par = info->par;
+ par->info = info;
+ par->client = client;
+
+ par->ops = (struct ssd1307fb_ops *)of_match_device(ssd1307fb_of_match,
+ &client->dev)->data;
+
+ par->reset = of_get_named_gpio(client->dev.of_node,
+ "reset-gpios", 0);
+ if (!gpio_is_valid(par->reset)) {
+ ret = -EINVAL;
+ goto fb_alloc_error;
+ }
+
+ if (of_property_read_u32(node, "solomon,width", &par->width))
+ par->width = 96;
+
+ if (of_property_read_u32(node, "solomon,height", &par->height))
+ par->width = 16;
+
+ if (of_property_read_u32(node, "solomon,page-offset", &par->page_offset))
+ par->page_offset = 1;
+
+ vmem_size = par->width * par->height / 8;
+
+ vmem = devm_kzalloc(&client->dev, vmem_size, GFP_KERNEL);
+ if (!vmem) {
+ dev_err(&client->dev, "Couldn't allocate graphical memory.\n");
+ ret = -ENOMEM;
+ goto fb_alloc_error;
+ }
+
+ info->fbops = &ssd1307fb_ops;
+ info->fix = ssd1307fb_fix;
+ info->fix.line_length = 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->var.red.length = 1;
+ info->var.red.offset = 0;
+ info->var.green.length = 1;
+ info->var.green.offset = 0;
+ info->var.blue.length = 1;
+ info->var.blue.offset = 0;
+
+ info->screen_base = (u8 __force __iomem *)vmem;
+ info->fix.smem_start = (unsigned long)vmem;
+ info->fix.smem_len = vmem_size;
+
+ fb_deferred_io_init(info);
+
+ ret = devm_gpio_request_one(&client->dev, par->reset,
+ GPIOF_OUT_INIT_HIGH,
+ "oled-reset");
+ if (ret) {
+ dev_err(&client->dev,
+ "failed to request gpio %d: %d\n",
+ par->reset, ret);
+ goto reset_oled_error;
+ }
+
+ i2c_set_clientdata(client, info);
+
+ /* Reset the screen */
+ gpio_set_value(par->reset, 0);
+ udelay(4);
+ gpio_set_value(par->reset, 1);
+ udelay(4);
+
+ if (par->ops->init) {
+ ret = par->ops->init(par);
+ if (ret)
+ goto reset_oled_error;
+ }
+
+ ret = register_framebuffer(info);
+ if (ret) {
+ dev_err(&client->dev, "Couldn't register the framebuffer\n");
+ goto panel_init_error;
+ }
+
+ dev_info(&client->dev, "fb%d: %s framebuffer device registered, using %d bytes of video memory\n", info->node, info->fix.id, vmem_size);
+
+ return 0;
+
+panel_init_error:
+ if (par->ops->remove)
+ par->ops->remove(par);
+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;
+
+ unregister_framebuffer(info);
+ if (par->ops->remove)
+ par->ops->remove(par);
+ fb_deferred_io_cleanup(info);
+ framebuffer_release(info);
+
+ return 0;
+}
+
+static const struct i2c_device_id ssd1307fb_i2c_id[] = {
+ { "ssd1306fb", 0 },
+ { "ssd1307fb", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id);
+
+static struct i2c_driver ssd1307fb_driver = {
+ .probe = ssd1307fb_probe,
+ .remove = ssd1307fb_remove,
+ .id_table = ssd1307fb_i2c_id,
+ .driver = {
+ .name = "ssd1307fb",
+ .of_match_table = ssd1307fb_of_match,
+ .owner = THIS_MODULE,
+ },
+};
+
+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");