1 // SPDX-License-Identifier: GPL-2.0
9  *    assigned HMC drive CD/DVD-ROM. It works as follows: First create the
42 #define HMCDRV_DEV_BUSY_DELAY	 500 /* delay between -EBUSY trials in ms */
43 #define HMCDRV_DEV_BUSY_RETRIES  3   /* number of retries on -EBUSY */
49 	umode_t mode;	 /* mode of device node (unused, zero) */
85  * hmcdrv_dev_name() - provides a naming hint for a device node in /dev
87  * @mode: file mode for device node created in /dev
118 	/* check for non-blocking access, which is really unsupported  in hmcdrv_dev_open()
120 	if (fp->f_flags & O_NONBLOCK)  in hmcdrv_dev_open()
121 		return -EINVAL;  in hmcdrv_dev_open()
123 	/* Because it makes no sense to open this device read-only (then a  in hmcdrv_dev_open()
126 	if ((fp->f_flags & O_ACCMODE) == O_RDONLY)  in hmcdrv_dev_open()
127 		return -EINVAL;  in hmcdrv_dev_open()
130 	 * device file open - so increment the reference count here  in hmcdrv_dev_open()
133 		return -ENODEV;  in hmcdrv_dev_open()
135 	fp->private_data = NULL; /* no command yet */  in hmcdrv_dev_open()
140 	pr_debug("open file '/dev/%pD' with return code %d\n", fp, rc);  in hmcdrv_dev_open()
149 	pr_debug("closing file '/dev/%pD'\n", fp);  in hmcdrv_dev_release()
150 	kfree(fp->private_data);  in hmcdrv_dev_release()
151 	fp->private_data = NULL;  in hmcdrv_dev_release()
164 		pos += fp->f_pos; /* new position stored in 'pos' */  in hmcdrv_dev_seek()
175 		if (fp->private_data) {  in hmcdrv_dev_seek()
176 			kfree(fp->private_data);  in hmcdrv_dev_seek()
177 			fp->private_data = NULL;  in hmcdrv_dev_seek()
183 		return -EINVAL;  in hmcdrv_dev_seek()
187 		return -EINVAL;  in hmcdrv_dev_seek()
189 	fp->f_pos = pos;  in hmcdrv_dev_seek()
205 		if (retlen != -EBUSY)  in hmcdrv_dev_transfer()
210 	} while (--trials > 0);  in hmcdrv_dev_transfer()
223 	if (((fp->f_flags & O_ACCMODE) == O_WRONLY) ||  in hmcdrv_dev_read()
224 	    (fp->private_data == NULL)) { /* no FTP cmd defined ? */  in hmcdrv_dev_read()
225 		return -EBADF;  in hmcdrv_dev_read()
228 	retlen = hmcdrv_dev_transfer((char *) fp->private_data,  in hmcdrv_dev_read()
231 	pr_debug("read from file '/dev/%pD' at %lld returns %zd/%zu\n",  in hmcdrv_dev_read()
249 	pr_debug("writing file '/dev/%pD' at pos. %lld with length %zd\n",  in hmcdrv_dev_write()
252 	if (!fp->private_data) { /* first expect a cmd write */  in hmcdrv_dev_write()
256 		fp->private_data = pdata;  in hmcdrv_dev_write()
260 	retlen = hmcdrv_dev_transfer((char *) fp->private_data,  in hmcdrv_dev_write()
265 	pr_debug("write to file '/dev/%pD' returned %zd\n", fp, retlen);  in hmcdrv_dev_write()
271  * hmcdrv_dev_init() - creates a HMC drive CD/DVD device
308 	/* Finally a device node in /dev has to be established (as 'mkdev'  in hmcdrv_dev_init()
310 	 * node name/mode function is optional (only for mode != 0600).  in hmcdrv_dev_init()
313 	hmcdrv_dev_class->devnode = hmcdrv_dev_name;  in hmcdrv_dev_init()
344  * hmcdrv_dev_exit() - destroys a HMC drive CD/DVD device