From: Allen Chen allen.chen@ite.com.tw
This add can let us find it6505 char device in the /dev file and use read/write function to let the driver be hold.
Signed-off-by: Allen Chen allen.chen@ite.com.tw
--- drivers/gpu/drm/bridge/ite-it6505.c | 131 ++++++++++++++++++++++++++++++++++++ 1 file changed, 131 insertions(+)
diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c index 13079a8..1529e61 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -70,6 +70,13 @@ /* if use this define will enable SHA debug */ /* #define SHA_DEBUG */
+/* register char device for it6505 */ +#define IT6505_CLASS_NAME "it6505_class" +#define IT6505_DEVICE_NAME "it6505_device" +#define IT6505_MAX_DEV 128 +/* The device major number */ +static int it6505_major_num; + enum sys_status { SYS_UNPLUG = 0, SYS_HPD, @@ -144,6 +151,8 @@ struct it6505 { struct it6505_platform_data pdata; struct mutex lock; struct regmap *regmap; + struct cdev cdev; + struct device class_dev; struct it6505_dp_port *port; /* thread sequence control */ struct semaphore sem_notifier; @@ -2502,6 +2511,80 @@ static int it6505_init_pdata(struct it6505 *it6505) return PTR_ERR_OR_ZERO(pdata->gpiod_reset); }
+static int it6505_open(struct inode *inode, struct file *file) +{ + struct it6505 *ctx = container_of(inode->i_cdev, struct it6505, cdev); + + DRM_DEBUG_DRIVER("[%s]: successful", __func__); + if (!ctx) + DRM_DEBUG_DRIVER("[%s]:get it6505 struct fail!", __func__); + file->private_data = ctx; + get_device(&ctx->class_dev); + return 0; +} + +static int it6505_release(struct inode *inode, struct file *file) +{ + struct it6505 *ctx = file->private_data; + + DRM_DEBUG_DRIVER("[%s]: successful", __func__); + put_device(&ctx->class_dev); + return 0; +} + +static ssize_t it6505_read(struct file *file, char *buf, + size_t count, loff_t *ptr) +{ + struct it6505 *ctx = file->private_data; + char kbuff[16]; + size_t len; + + DRM_DEBUG_DRIVER("[%s]start count=%zu", __func__, count); + DRM_DEBUG_DRIVER("it6505_drv_hold:%d", ctx->it6505_drv_hold); + len = snprintf(kbuff, sizeof(kbuff), "%d", ctx->it6505_drv_hold); + len = min3(count, len, sizeof(kbuff)); + return copy_to_user(buf, kbuff, len) ? -EFAULT : len; +} + +static ssize_t it6505_write(struct file *file, const char *buff, + size_t count, loff_t *ptr) +{ + struct it6505 *ctx = file->private_data; + char kbuff[16]; + int num; + + DRM_DEBUG_DRIVER("[%s]start count=%zu", __func__, count); + count = min(count, sizeof(kbuff) - 1); + if (copy_from_user(kbuff, buff, count)) + return -EFAULT; + kbuff[count] = '\0'; + if (kstrtoint(kbuff, 10, &num) < 0) + return -EINVAL; + ctx->it6505_drv_hold = num; + DRM_DEBUG_DRIVER("set it6505_drv_hold:%d", ctx->it6505_drv_hold); + return count; +} + +static struct class it6505_class_file = { + .owner = THIS_MODULE, + .name = IT6505_CLASS_NAME, +}; + +static const struct file_operations it6505_fops = { + .owner = THIS_MODULE, + .read = it6505_read, + .write = it6505_write, + .open = it6505_open, + .release = it6505_release +}; + +static void it6505_release_device(struct device *dev) +{ + struct it6505 *ctx = container_of(dev, struct it6505, class_dev); + + kfree(ctx); +} + static int it6505_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -2575,8 +2658,38 @@ static int it6505_i2c_probe(struct i2c_client *client, ctx->bridge.funcs = &it6505_bridge_funcs;
drm_bridge_add(&ctx->bridge); + device_initialize(&ctx->class_dev); + ctx->class_dev.parent = &client->dev; + ctx->class_dev.release = it6505_release_device; + cdev_init(&ctx->cdev, &it6505_fops); + err = dev_set_name(&ctx->class_dev, "%s", IT6505_DEVICE_NAME); + DRM_DEBUG_DRIVER("[%s] dev_set_name:%s", + __func__, err ? "failed" : "success"); + if (err) { + DRM_DEBUG_DRIVER("dev_set_name failed => %d", err); + goto put_class_dev; + } + /* + * Add the class device + * Link to the character device for creating the /dev entry + * in devtmpfs. + */ + ctx->class_dev.devt = MKDEV(it6505_major_num, 0); + ctx->class_dev.class = &it6505_class_file; + + /* We can now add the sysfs class, we know which parameter to show */ + err = cdev_device_add(&ctx->cdev, &ctx->class_dev); + if (err) { + DRM_DEBUG_DRIVER("cdev_device_add failed => %d", + err); + goto put_class_dev; + } DRM_DEBUG_DRIVER("[%s]end", __func__); return 0; + +put_class_dev: + put_device(&ctx->class_dev); + return err; }
static int it6505_remove(struct i2c_client *client) @@ -2616,16 +2729,34 @@ struct i2c_driver it6505_i2c_driver = {
static int __init it6505_init(void) { + int err; + dev_t dev = 0; + DRM_DEBUG_DRIVER("[%s]start", __func__); + /* Register the device class */ + err = class_register(&it6505_class_file); + err = alloc_chrdev_region(&dev, 0, IT6505_MAX_DEV, + IT6505_DEVICE_NAME); + it6505_major_num = MAJOR(dev); + if (err < 0) { + DRM_DEBUG_DRIVER("alloc_chrdev_region() fail!"); + goto failed_chrdevreg; + } i2c_add_driver(&it6505_i2c_driver); DRM_DEBUG_DRIVER("[%s]end", __func__); return 0; + +failed_chrdevreg: + class_unregister(&it6505_class_file); + return err; }
static void __exit it6505_exit(void) { DRM_DEBUG_DRIVER("[%s]start", __func__); i2c_del_driver(&it6505_i2c_driver); + unregister_chrdev(it6505_major_num, IT6505_DEVICE_NAME); + class_unregister(&it6505_class_file); DRM_DEBUG_DRIVER("[%s]end", __func__); }