drivers/spi/spidev.c

25 #include <linux/spi/spidev.h>
106 spidev_sync(struct spidev_data *spidev, struct spi_message *message)
111 	mutex_lock(&spidev->spi_lock);
112 	spi = spidev->spi;
119 	mutex_unlock(&spidev->spi_lock);
124 spidev_sync_write(struct spidev_data *spidev, size_t len)
127 			.tx_buf		= spidev->tx_buffer,
129 			.speed_hz	= spidev->speed_hz,
135 	return spidev_sync(spidev, &m);
139 spidev_sync_read(struct spidev_data *spidev, size_t len)
142 			.rx_buf		= spidev->rx_buffer,
144 			.speed_hz	= spidev->speed_hz,
150 	return spidev_sync(spidev, &m);
159 	struct spidev_data	*spidev;
166 	spidev = filp->private_data;
168 	mutex_lock(&spidev->buf_lock);
169 	status = spidev_sync_read(spidev, count);
173 		missing = copy_to_user(buf, spidev->rx_buffer, status);
179 	mutex_unlock(&spidev->buf_lock);
189 	struct spidev_data	*spidev;
197 	spidev = filp->private_data;
199 	mutex_lock(&spidev->buf_lock);
200 	missing = copy_from_user(spidev->tx_buffer, buf, count);
202 		status = spidev_sync_write(spidev, count);
205 	mutex_unlock(&spidev->buf_lock);
210 static int spidev_message(struct spidev_data *spidev,
230 	tx_buf = spidev->tx_buffer;
231 	rx_buf = spidev->rx_buffer;
291 			k_tmp->speed_hz = spidev->speed_hz;
293 		dev_dbg(&spidev->spi->dev,
299 			k_tmp->bits_per_word ? : spidev->spi->bits_per_word,
302 			k_tmp->speed_hz ? : spidev->spi->max_speed_hz);
307 	status = spidev_sync_unlocked(spidev->spi, &msg);
358 	struct spidev_data	*spidev;
372 	spidev = filp->private_data;
373 	mutex_lock(&spidev->spi_lock);
374 	spi = spi_dev_get(spidev->spi);
376 		mutex_unlock(&spidev->spi_lock);
388 	mutex_lock(&spidev->buf_lock);
412 		retval = put_user(spidev->speed_hz, (__u32 __user *)arg);
488 			spidev->speed_hz = tmp;
489 			dev_dbg(&spi->dev, "%d Hz (max)\n", spidev->speed_hz);
508 		retval = spidev_message(spidev, ioc, n_ioc);
513 	mutex_unlock(&spidev->buf_lock);
515 	mutex_unlock(&spidev->spi_lock);
526 	struct spidev_data		*spidev;
536 	spidev = filp->private_data;
537 	mutex_lock(&spidev->spi_lock);
538 	spi = spi_dev_get(spidev->spi);
540 		mutex_unlock(&spidev->spi_lock);
545 	mutex_lock(&spidev->buf_lock);
563 	retval = spidev_message(spidev, ioc, n_ioc);
567 	mutex_unlock(&spidev->buf_lock);
569 	mutex_unlock(&spidev->spi_lock);
589 	struct spidev_data	*spidev = NULL, *iter;
597 			spidev = iter;
602 	if (!spidev) {
603 		pr_debug("spidev: nothing for minor %d\n", iminor(inode));
607 	if (!spidev->tx_buffer) {
608 		spidev->tx_buffer = kmalloc(bufsiz, GFP_KERNEL);
609 		if (!spidev->tx_buffer) {
615 	if (!spidev->rx_buffer) {
616 		spidev->rx_buffer = kmalloc(bufsiz, GFP_KERNEL);
617 		if (!spidev->rx_buffer) {
623 	spidev->users++;
624 	filp->private_data = spidev;
631 	kfree(spidev->tx_buffer);
632 	spidev->tx_buffer = NULL;
640 	struct spidev_data	*spidev;
644 	spidev = filp->private_data;
647 	mutex_lock(&spidev->spi_lock);
649 	dofree = (spidev->spi == NULL);
650 	mutex_unlock(&spidev->spi_lock);
653 	spidev->users--;
654 	if (!spidev->users) {
656 		kfree(spidev->tx_buffer);
657 		spidev->tx_buffer = NULL;
659 		kfree(spidev->rx_buffer);
660 		spidev->rx_buffer = NULL;
663 			kfree(spidev);
665 			spidev->speed_hz = spidev->spi->max_speed_hz;
669 		spi_slave_abort(spidev->spi);
699 	.name = "spidev",
718  * spidev should never be referenced in DT without a specific compatible string,
723 	if (device_property_match_string(dev, "compatible", "spidev") < 0)
726 	dev_err(dev, "spidev listed directly in DT is not supported\n");
771 	struct spidev_data	*spidev;
783 	spidev = kzalloc(sizeof(*spidev), GFP_KERNEL);
784 	if (!spidev)
788 	spidev->spi = spi;
789 	mutex_init(&spidev->spi_lock);
790 	mutex_init(&spidev->buf_lock);
792 	INIT_LIST_HEAD(&spidev->device_entry);
802 		spidev->devt = MKDEV(SPIDEV_MAJOR, minor);
803 		dev = device_create(&spidev_class, &spi->dev, spidev->devt,
804 				    spidev, "spidev%d.%d",
813 		list_add(&spidev->device_entry, &device_list);
817 	spidev->speed_hz = spi->max_speed_hz;
820 		spi_set_drvdata(spi, spidev);
822 		kfree(spidev);
829 	struct spidev_data	*spidev = spi_get_drvdata(spi);
834 	mutex_lock(&spidev->spi_lock);
835 	spidev->spi = NULL;
836 	mutex_unlock(&spidev->spi_lock);
838 	list_del(&spidev->device_entry);
839 	device_destroy(&spidev_class, spidev->devt);
840 	clear_bit(MINOR(spidev->devt), minors);
841 	if (spidev->users == 0)
842 		kfree(spidev);
848 		.name =		"spidev",
903 MODULE_ALIAS("spi:spidev");