how to write display driver - driver

Question

I am writing display drivers for micro oled.
board is dart4460 (omap4460) which provides dss(display subsystem).
so I am writing drivers using dss.
but I dont know what I wrote is right or not
oled display use dpi interface and i2c for commands
I referred to pico dlp projector driver source which uses dpi and i2c.
here are datasheets
dart4460: http://www.variscite.com/images/DART-4460-DS_107.pdf
micro oled display: https://www.dropbox.com/s/ixpws4qzo3ttj6e/SVGA050.pdf?dl=0
Code:
panel-svga.c
#define SLAVE_ADDR_READ 0x1F
#define SLAVW_ADDR_WRITE 0x1E
struct svga050_i2c_data {
struct mutex xfer_lock;
};
struct svga050_data {
struct i2c_client *client;
struct mutex lock;
};
static struct i2c_board_info svga050_i2c_board_info = {
I2C_BOARD_INFO("svga050_i2c_drive",SLAVE_ADDR_WRITE);
}
static struct omap_video_timings svga050_timings = {
.x_res = 800,
.y_res = 600,
.pixel_clock = 40000,
.hsw = 128,
.hfp = 40,
.hbp = 88,
.vsw = 4,
.vfp = 1,
.vbp = 23,
};
static int svga050_panel_power_on(struct omap_dss_device *dssdev)
{
int r;
if (dssdev->state == OMAP_DSS_DISPLAY_ACTIVE)
return 0;
r = omapdss_dpi_display_enable(dssdev);
if (r)
goto err0;
if (dssdev->platform_enable) {
r = dssdev->platform_enable(dssdev);
if (r)
goto err1;
}
return 0;
err1:
omapdss_dpi_display_disable(dssdev);
err0:
return r;
}
static void svga050_panel_power_off(struct omap_dss_device *dssdev)
{
if (dssdev->state != OMAP_DSS_DISPLAY_ACTIVE)
return;
if (dssdev->platform_disable)
dssdev->platform_disable(dssdev);
omapdss_dpi_display_disable(dssdev);
}
static inline struct svga050_panel_data *get_panel_data(const struct omap_dss_device *dssdev)
{
return (struct svga050_panel_data *)dssdev->data;
}
static int svga050_panel_probe(struct omap_dss_device *dssdev)
{
struct svga050_data *svga_data;
struct i2c_adapter *adapter;
struct i2c_client *svga_i2c_client;
struct svga050_panel_data *svga_pdata=get_panel_data(dssdev);
int r;
dssdev->panel.config = OMAP_DSS_LCD_TFT | OMAP_DSS_LCD_IVS |
OMAP_DSS_LCD_IHS;
dssdev->panel.timings = svga050_timings;
svga_data = devm_kzalloc(&dssdev->dev,sizeof(*svga_data), GFP_KERNEL);
if (!svga_data) {
r = -ENOMEM;
goto err;
}
mutex_init(&ld->lock);
dev_set_drvdata(&dssdev->dev, ld);
return 0;
err:
return r;
}
static void svga050_panel_remove(struct omap_dss_device *dssdev)
{
struct svga050_data *ld = dev_get_drvdata(&dssdev->dev);
kfree(ld);
}
static int svga050_panel_enable(struct omap_dss_device *dssdev)
{
struct svga050_data *ld = dev_get_drvdata(&dssdev->dev);
int r;
mutex_lock(&ld->lock);
r = svga050_panel_power_on(dssdev);
if (r)
goto err;
dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
mutex_unlock(&ld->lock);
return 0;
err:
mutex_unlock(&ld->lock);
return r;
}
static void svga050_panel_disable(struct omap_dss_device *dssdev)
{
struct svga050_data *ld = dev_get_drvdata(&dssdev->dev);
mutex_lock(&ld->lock);
svga050_panel_power_off(dssdev);
dssdev->state = OMAP_DSS_DISPLAY_DISABLED;
mutex_unlock(&ld->lock);
}
static int svga050_panel_suspend(struct omap_dss_device *dssdev)
{
struct svga050_data *ld = dev_get_drvdata(&dssdev->dev);
mutex_lock(&ld->lock);
svga050_panel_power_off(dssdev);
dssdev->state = OMAP_DSS_DISPLAY_SUSPENDED;
mutex_unlock(&ld->lock);
return 0;
}
static int svga050_panel_resume(struct omap_dss_device *dssdev)
{
struct svga050_data *ld = dev_get_drvdata(&dssdev->dev);
int r;
mutex_lock(&ld->lock);
r = svga050_panel_power_on(dssdev);
if (r)
goto err;
dssdev->state = OMAP_DSS_DISPLAY_ACTIVE;
mutex_unlock(&ld->lock);
return 0;
err:
mutex_unlock(&ld->lock);
return r;
}
static struct omap_dss_driver svga050_driver = {
.probe = svga050_panel_probe,
.remove = svga050_panel_remove,
.enable = svga050_panel_enable,
.disable = svga050_panel_disable,
.suspend = svga050_panel_suspend,
.resume = svga050_panel_resume,
.driver = {
.name = "svga050",
.owner = THIS_MODULE,
},
};
static int svga050_i2c_read(struct i2c_client *client, u8 reg)
{
u8 read_cmd[] = { SLAVE_ADDR_READ, reg }, data;
struct svga050_i2c_data *picodlp_i2c_data = i2c_get_clientdata(client);
struct i2c_msg msg[2];
mutex_lock(&svga050_i2c_data->xfer_lock);
msg[0].addr = client->addr;
msg[0].flags = 0;
msg[0].len = 2;
msg[0].buf = read_cmd;
msg[1].addr = client->addr;
msg[1].flags = I2C_M_RD;
msg[1].len = 2;
msg[1].buf = data;
i2c_transfer(client->adapter, msg, 2);
mutex_unlock(&svga050_i2c_data->xfer_lock);
return data;
}
static int svga050_i2c_write(struct i2c_client *client, u8 reg, u8 value)
{
u8 data[2];
int i;
struct i2c_msg msg;
int i, r, msg_count = 1;
struct svga050_i2c_data *picodlp_i2c_data = i2c_get_clientdata(client);
data[0] = reg;
data[1] = value;
mutex_lock(&svga050_i2c_data->xfer_lock);
msg.addr = client->addr;
msg.flags = 0;
msg.len = 2;
msg.buf = data;
r = i2c_transfer(client->adapter, &msg, msg_count);
mutex_unlock(&svga050_i2c_data->xfer_lock);
/*
* i2c_transfer returns:
* number of messages sent in case of success
* a negative error number in case of failure
*/
if (r != msg_count)
goto err;
/* In case of success */
for (i = 0; i < 2; i++)
dev_dbg(&client->dev,
"addr %x bw 0x%02x[%d]: 0x%02x\n",
client->addr, data[0] + i, i, data[i]);
return 0;
err:
dev_err(&client->dev, "svga050_i2c_write error\n");
return r;
}
static int svga050_i2c_write_array(struct i2c_client *client,
const struct svga050_i2c_command commands[],
int count)
{
int i, r = 0;
for (i = 0; i < count; i++) {
r = svga050_i2c_write(client, commands[i].reg,
commands[i].value);
if (r)
return r;
}
return r;
}
static void init_svga050_panel(struct spi_device *spi)
{
}
static int __devinit svga050_panel_i2c_probe(struct i2c_client *client,const struct i2c_device_id *id)
{
struct svga050_i2c_data *svga_i2c_data;
svga_i2c_data=kzalloc(sizeof(struct svga050_i2c_data),GFP_KERNEL);
if(svga_i2c_data == NULL)
return -ENOMEM;
i2c_set_clientdata(client,svga_i2c_data);
mutex_init(&svga_i2c_data->xfer_lock);
dev_err(&client->dev,"svga i2c initialized\n");
return 0;
}
static int __devexit svga050_panel_i2c_remove(struct i2c_client *client)
{
struct svga050_i2c_data *sd1= i2c_get_clientdata(client);
i2c_set_clientdata(client,NULL);
kfree(sd1);
return 0;
}
static const struct i2c_device_id svga050_i2c_idtable[]={
{"svga050_i2c_driver",0},
{},
};
static struct i2c_driver svga050_i2c_driver = {
.driver = {
.name = "svga050_i2c",
.owner = THIS_MODULE,
},
.probe = svga050_panel_i2c_probe,
.remove = __exit_p(svga050_panel_i2c_remove),
.id_table = svga050_i2c_idtable,
};
static int __init svga050_panel_drv_init(void)
{
int r;
r= i2c_add_driver(&svga050_i2c_driver);
if(r < 0){
printk(KERN_WARNING "svga050 i2c driver registration failed\n");
return r;
}
r=omap_dss_register_driver(&svga050_driver);
if(r < 0){
printk(KERN_WARNING "svga050 dss driver registration failed\n");
i2c_del_driver(&svga050_i2c_driver);
}
return r;
}
static void __exit svga050_panel_drv_exit(void)
{
omap_dss_unregister_driver(&svga050_driver);
i2c_del_driver(&svga050_i2c_driver);
}
module_init(svga050_panel_drv_init);
module_exit(svga050_panel_drv_exit);
MODULE_LICENSE("GPL");
Board.c
static struct omap_dss_device svga050_device = {
.name = "svga050",
.driver_name = "svga050",
.type = OMAP_DISPLAY_TYPE_DPI,
.phy.dpi.data_lines = 24,
.channel = OMAP_DSS_CHANNEL_LCD2,
.platform_enable = svga050_panel_enable_picodlp,
.platform_disable = svga050_panel_disable_picodlp,
.data = &svga050_pdata,
};
static struct omap_dss_device *svga050_dss_devices[] = {
&svga050_device,
};
static struct picodlp_panel_data sdp4430_picodlp_pdata = {
.svga050_adapter_id = 2,
};
my questions are :
My code is right?
I don't know how to write display init code by seeing datasheet.
Can I write display init code by seeing this datasheet ?
In panel_probe function, how can I get adapter ID ?
how do I choose adapter I ?
Is it right that I should write only i2c slave driver code in panel code ?
How can I select I2C master ? I want to use I2C3 or I2C4 for display commands