diff options
| -rw-r--r-- | Documentation/devicetree/bindings/video/ssd1307fb.txt | 24 | ||||
| -rw-r--r-- | drivers/video/Kconfig | 15 | ||||
| -rw-r--r-- | drivers/video/Makefile | 1 | ||||
| -rw-r--r-- | drivers/video/ssd1307fb.c | 396 |
4 files changed, 436 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/video/ssd1307fb.txt b/Documentation/devicetree/bindings/video/ssd1307fb.txt new file mode 100644 index 00000000000..3d0060cff06 --- /dev/null +++ b/Documentation/devicetree/bindings/video/ssd1307fb.txt @@ -0,0 +1,24 @@ +* Solomon SSD1307 Framebuffer Driver + +Required properties: + - compatible: Should be "solomon,ssd1307fb-<bus>". The only supported bus for + now is i2c. + - reg: Should contain address of the controller on the I2C bus. Most likely + 0x3c or 0x3d + - pwm: Should contain the pwm to use according to the OF device tree PWM + specification [0] + - reset-gpios: Should contain the GPIO used to reset the OLED display + +Optional properties: + - reset-active-low: Is the reset gpio is active on physical low? + +[0]: Documentation/devicetree/bindings/pwm/pwm.txt + +Examples: +ssd1307: oled@3c { + compatible = "solomon,ssd1307fb-i2c"; + reg = <0x3c>; + pwms = <&pwm 4 3000>; + reset-gpios = <&gpio2 7>; + reset-active-low; +}; diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig index 9018a90b458..9c31277b3a8 100644 --- a/drivers/video/Kconfig +++ b/drivers/video/Kconfig @@ -2442,4 +2442,19 @@ config FB_SH_MOBILE_MERAM Up to 4 memory channels can be configured, allowing 4 RGB or 2 YCbCr framebuffers to be configured. +config FB_SSD1307 + tristate "Solomon SSD1307 framebuffer support" + depends on FB && I2C + depends on OF + depends on GENERIC_GPIO + select FB_SYS_FOPS + select FB_SYS_FILLRECT + select FB_SYS_COPYAREA + select FB_SYS_IMAGEBLIT + select FB_DEFERRED_IO + select PWM + help + This driver implements support for the Solomon SSD1307 + OLED controller over I2C. + endmenu diff --git a/drivers/video/Makefile b/drivers/video/Makefile index 23e948ebfab..768a137a1ba 100644 --- a/drivers/video/Makefile +++ b/drivers/video/Makefile @@ -161,6 +161,7 @@ obj-$(CONFIG_FB_BFIN_7393) += bfin_adv7393fb.o obj-$(CONFIG_FB_MX3) += mx3fb.o obj-$(CONFIG_FB_DA8XX) += da8xx-fb.o obj-$(CONFIG_FB_MXS) += mxsfb.o +obj-$(CONFIG_FB_SSD1307) += ssd1307fb.o # the test framebuffer is last obj-$(CONFIG_FB_VIRTUAL) += vfb.o diff --git a/drivers/video/ssd1307fb.c b/drivers/video/ssd1307fb.c new file mode 100644 index 00000000000..6101f5c2f62 --- /dev/null +++ b/drivers/video/ssd1307fb.c @@ -0,0 +1,396 @@ +/* + * Driver for the Solomon SSD1307 OLED controler + * + * 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_WIDTH 96 +#define SSD1307FB_HEIGHT 16 + +#define SSD1307FB_DATA 0x40 +#define SSD1307FB_COMMAND 0x80 + +#define SSD1307FB_CONTRAST 0x81 +#define SSD1307FB_SEG_REMAP_ON 0xa1 +#define SSD1307FB_DISPLAY_OFF 0xae +#define SSD1307FB_DISPLAY_ON 0xaf +#define SSD1307FB_START_PAGE_ADDRESS 0xb0 + +struct ssd1307fb_par { + struct i2c_client *client; + struct fb_info *info; + struct pwm_device *pwm; + u32 pwm_period; + int reset; +}; + +static struct fb_fix_screeninfo ssd1307fb_fix __devinitdata = { + .id = "Solomon SSD1307", + .type = FB_TYPE_PACKED_PIXELS, + .visual = FB_VISUAL_MONO10, + .xpanstep = 0, + .ypanstep = 0, + .ywrapstep = 0, + .line_length = SSD1307FB_WIDTH / 8, + .accel = FB_ACCEL_NONE, +}; + +static struct fb_var_screeninfo ssd1307fb_var __devinitdata = { + .xres = SSD1307FB_WIDTH, + .yres = SSD1307FB_HEIGHT, + .xres_virtual = SSD1307FB_WIDTH, + .yres_virtual = SSD1307FB_HEIGHT, + .bits_per_pixel = 1, +}; + +static int ssd1307fb_write_array(struct i2c_client *client, u8 type, u8 *cmd, u32 len) +{ + u8 *buf; + int ret = 0; + + buf = kzalloc(len + 1, GFP_KERNEL); + if (!buf) { + dev_err(&client->dev, "Couldn't allocate sending buffer.\n"); + return -ENOMEM; + } + + buf[0] = type; + memcpy(buf + 1, cmd, len); + + ret = i2c_master_send(client, buf, len + 1); + if (ret != len + 1) { + dev_err(&client->dev, "Couldn't send I2C command.\n"); + goto error; + } + +error: + kfree(buf); + return ret; +} + +static inline int ssd1307fb_write_cmd_array(struct i2c_client *client, u8 *cmd, u32 len) +{ + return ssd1307fb_write_array(client, SSD1307FB_COMMAND, cmd, len); +} + +static inline int ssd1307fb_write_cmd(struct i2c_client *client, u8 cmd) +{ + return ssd1307fb_write_cmd_array(client, &cmd, 1); +} + +static inline int ssd1307fb_write_data_array(struct i2c_client *client, u8 *cmd, u32 len) +{ + return ssd1307fb_write_array(client, SSD1307FB_DATA, cmd, len); +} + +static inline int ssd1307fb_write_data(struct i2c_client *client, u8 data) +{ + return ssd1307fb_write_data_array(client, &data, 1); +} + +static void ssd1307fb_update_display(struct ssd1307fb_par *par) +{ + u8 *vmem = par->info->screen_base; + int i, j, k; + + /* + * 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 < (SSD1307FB_HEIGHT / 8); i++) { + ssd1307fb_write_cmd(par->client, SSD1307FB_START_PAGE_ADDRESS + (i + 1)); + ssd1307fb_write_cmd(par->client, 0x00); + ssd1307fb_write_cmd(par->client, 0x10); + + for (j = 0; j < SSD1307FB_WIDTH; j++) { + u8 buf = 0; + for (k = 0; k < 8; k++) { + u32 page_length = SSD1307FB_WIDTH * i; + u32 index = page_length + (SSD1307FB_WIDTH * k + j) / 8; + u8 byte = *(vmem + index); + u8 bit = byte & (1 << (7 - (j % 8))); + bit = bit >> (7 - (j % 8)); + buf |= bit << k; + } + ssd1307fb_write_data(par->client, buf); + } + } +} + + +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 __devinit ssd1307fb_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct fb_info *info; + u32 vmem_size = SSD1307FB_WIDTH * SSD1307FB_HEIGHT / 8; + struct ssd1307fb_par *par; + u8 *vmem; + int ret; + + if (!client->dev.of_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; + } + + 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->fbdefio = &ssd1307fb_defio; + + info->var = ssd1307fb_var; + 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); + + par = info->par; + par->info = info; + par->client = client; + + par->reset = of_get_named_gpio(client->dev.of_node, + "reset-gpios", 0); + if (!gpio_is_valid(par->reset)) { + ret = -EINVAL; + goto reset_oled_error; + } + + 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; + } + + par->pwm = pwm_get(&client->dev, NULL); + if (IS_ERR(par->pwm)) { + dev_err(&client->dev, "Could not get PWM from device tree!\n"); + ret = PTR_ERR(par->pwm); + goto pwm_error; + } + + par->pwm_period = pwm_get_period(par->pwm); + + dev_dbg(&client->dev, "Using PWM%d with a %dns period.\n", par->pwm->pwm, par->pwm_period); + + ret = register_framebuffer(info); + if (ret) { + dev_err(&client->dev, "Couldn't register the framebuffer\n"); + goto fbreg_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); + + /* Enable the PWM */ + pwm_config(par->pwm, par->pwm_period / 2, par->pwm_period); + pwm_enable(par->pwm); + + /* Map column 127 of the OLED to segment 0 */ + ret = ssd1307fb_write_cmd(client, SSD1307FB_SEG_REMAP_ON); + if (ret < 0) { + dev_err(&client->dev, "Couldn't remap the screen.\n"); + goto remap_error; + } + + /* Turn on the display */ + ret = ssd1307fb_write_cmd(client, SSD1307FB_DISPLAY_ON); + if (ret < 0) { + dev_err(&client->dev, "Couldn't turn the display on.\n"); + goto remap_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; + +remap_error: + unregister_framebuffer(info); + pwm_disable(par->pwm); +fbreg_error: + pwm_put(par->pwm); +pwm_error: +reset_oled_error: + fb_deferred_io_cleanup(info); +fb_alloc_error: + framebuffer_release(info); + return ret; +} + +static int __devexit ssd1307fb_remove(struct i2c_client *client) +{ + struct fb_info *info = i2c_get_clientdata(client); + struct ssd1307fb_par *par = info->par; + + unregister_framebuffer(info); + pwm_disable(par->pwm); + pwm_put(par->pwm); + fb_deferred_io_cleanup(info); + framebuffer_release(info); + + return 0; +} + +static const struct i2c_device_id ssd1307fb_i2c_id[] = { + { "ssd1307fb", 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ssd1307fb_i2c_id); + +static const struct of_device_id ssd1307fb_of_match[] = { + { .compatible = "solomon,ssd1307fb-i2c" }, + {}, +}; +MODULE_DEVICE_TABLE(of, ssd1307fb_of_match); + +static struct i2c_driver ssd1307fb_driver = { + .probe = ssd1307fb_probe, + .remove = __devexit_p(ssd1307fb_remove), + .id_table = ssd1307fb_i2c_id, + .driver = { + .name = "ssd1307fb", + .of_match_table = of_match_ptr(ssd1307fb_of_match), + .owner = THIS_MODULE, + }, +}; + +module_i2c_driver(ssd1307fb_driver); + +MODULE_DESCRIPTION("FB driver for the Solomon SSD1307 OLED controler"); +MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>"); +MODULE_LICENSE("GPL"); |