diff options
| -rw-r--r-- | drivers/iio/iio_core.h | 4 | ||||
| -rw-r--r-- | drivers/iio/industrialio-buffer.c | 127 | ||||
| -rw-r--r-- | drivers/iio/industrialio-core.c | 1 | ||||
| -rw-r--r-- | include/linux/iio/buffer.h | 7 | ||||
| -rw-r--r-- | include/linux/iio/buffer_impl.h | 11 |
5 files changed, 148 insertions, 2 deletions
diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h index 8f4a9b264962..61e318431de9 100644 --- a/drivers/iio/iio_core.h +++ b/drivers/iio/iio_core.h @@ -68,12 +68,15 @@ __poll_t iio_buffer_poll_wrapper(struct file *filp, struct poll_table_struct *wait); ssize_t iio_buffer_read_wrapper(struct file *filp, char __user *buf, size_t n, loff_t *f_ps); +ssize_t iio_buffer_write_wrapper(struct file *filp, const char __user *buf, + size_t n, loff_t *f_ps); int iio_buffers_alloc_sysfs_and_mask(struct iio_dev *indio_dev); void iio_buffers_free_sysfs_and_mask(struct iio_dev *indio_dev); #define iio_buffer_poll_addr (&iio_buffer_poll_wrapper) #define iio_buffer_read_outer_addr (&iio_buffer_read_wrapper) +#define iio_buffer_write_outer_addr (&iio_buffer_write_wrapper) void iio_disable_all_buffers(struct iio_dev *indio_dev); void iio_buffer_wakeup_poll(struct iio_dev *indio_dev); @@ -83,6 +86,7 @@ void iio_device_detach_buffers(struct iio_dev *indio_dev); #define iio_buffer_poll_addr NULL #define iio_buffer_read_outer_addr NULL +#define iio_buffer_write_outer_addr NULL static inline int iio_buffers_alloc_sysfs_and_mask(struct iio_dev *indio_dev) { diff --git a/drivers/iio/industrialio-buffer.c b/drivers/iio/industrialio-buffer.c index 4209e933ab80..b884d78657cb 100644 --- a/drivers/iio/industrialio-buffer.c +++ b/drivers/iio/industrialio-buffer.c @@ -120,6 +120,9 @@ static ssize_t iio_buffer_read(struct file *filp, char __user *buf, if (!rb || !rb->access->read) return -EINVAL; + if (rb->direction != IIO_BUFFER_DIRECTION_IN) + return -EPERM; + datum_size = rb->bytes_per_datum; /* @@ -161,6 +164,65 @@ static ssize_t iio_buffer_read(struct file *filp, char __user *buf, return ret; } +static size_t iio_buffer_space_available(struct iio_buffer *buf) +{ + if (buf->access->space_available) + return buf->access->space_available(buf); + + return SIZE_MAX; +} + +static ssize_t iio_buffer_write(struct file *filp, const char __user *buf, + size_t n, loff_t *f_ps) +{ + struct iio_dev_buffer_pair *ib = filp->private_data; + struct iio_buffer *rb = ib->buffer; + struct iio_dev *indio_dev = ib->indio_dev; + DEFINE_WAIT_FUNC(wait, woken_wake_function); + int ret; + size_t written; + + if (!indio_dev->info) + return -ENODEV; + + if (!rb || !rb->access->write) + return -EINVAL; + + if (rb->direction != IIO_BUFFER_DIRECTION_OUT) + return -EPERM; + + written = 0; + add_wait_queue(&rb->pollq, &wait); + do { + if (indio_dev->info == NULL) + return -ENODEV; + + if (!iio_buffer_space_available(rb)) { + if (signal_pending(current)) { + ret = -ERESTARTSYS; + break; + } + + wait_woken(&wait, TASK_INTERRUPTIBLE, + MAX_SCHEDULE_TIMEOUT); + continue; + } + + ret = rb->access->write(rb, n - written, buf + written); + if (ret == 0 && (filp->f_flags & O_NONBLOCK)) + ret = -EAGAIN; + + if (ret > 0) { + written += ret; + if (written != n && !(filp->f_flags & O_NONBLOCK)) + continue; + } + } while (ret == 0); + remove_wait_queue(&rb->pollq, &wait); + + return ret < 0 ? ret : n; +} + /** * iio_buffer_poll() - poll the buffer to find out if it has data * @filp: File structure pointer for device access @@ -181,8 +243,18 @@ static __poll_t iio_buffer_poll(struct file *filp, return 0; poll_wait(filp, &rb->pollq, wait); - if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) - return EPOLLIN | EPOLLRDNORM; + + switch (rb->direction) { + case IIO_BUFFER_DIRECTION_IN: + if (iio_buffer_ready(indio_dev, rb, rb->watermark, 0)) + return EPOLLIN | EPOLLRDNORM; + break; + case IIO_BUFFER_DIRECTION_OUT: + if (iio_buffer_space_available(rb)) + return EPOLLOUT | EPOLLWRNORM; + break; + } + return 0; } @@ -199,6 +271,19 @@ ssize_t iio_buffer_read_wrapper(struct file *filp, char __user *buf, return iio_buffer_read(filp, buf, n, f_ps); } +ssize_t iio_buffer_write_wrapper(struct file *filp, const char __user *buf, + size_t n, loff_t *f_ps) +{ + struct iio_dev_buffer_pair *ib = filp->private_data; + struct iio_buffer *rb = ib->buffer; + + /* check if buffer was opened through new API */ + if (test_bit(IIO_BUSY_BIT_POS, &rb->flags)) + return -EBUSY; + + return iio_buffer_write(filp, buf, n, f_ps); +} + __poll_t iio_buffer_poll_wrapper(struct file *filp, struct poll_table_struct *wait) { @@ -231,6 +316,15 @@ void iio_buffer_wakeup_poll(struct iio_dev *indio_dev) } } +int iio_pop_from_buffer(struct iio_buffer *buffer, void *data) +{ + if (!buffer || !buffer->access || !buffer->access->remove_from) + return -EINVAL; + + return buffer->access->remove_from(buffer, data); +} +EXPORT_SYMBOL_GPL(iio_pop_from_buffer); + void iio_buffer_init(struct iio_buffer *buffer) { INIT_LIST_HEAD(&buffer->demux_list); @@ -1156,6 +1250,10 @@ int iio_update_buffers(struct iio_dev *indio_dev, if (insert_buffer == remove_buffer) return 0; + if (insert_buffer && + (insert_buffer->direction == IIO_BUFFER_DIRECTION_OUT)) + return -EINVAL; + mutex_lock(&iio_dev_opaque->info_exist_lock); mutex_lock(&indio_dev->mlock); @@ -1277,6 +1375,22 @@ static ssize_t iio_dma_show_data_available(struct device *dev, return sysfs_emit(buf, "%zu\n", iio_buffer_data_available(buffer)); } +static ssize_t direction_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct iio_buffer *buffer = to_iio_dev_attr(attr)->buffer; + + switch (buffer->direction) { + case IIO_BUFFER_DIRECTION_IN: + return sprintf(buf, "in\n"); + case IIO_BUFFER_DIRECTION_OUT: + return sprintf(buf, "out\n"); + default: + return -EINVAL; + } +} + static DEVICE_ATTR(length, S_IRUGO | S_IWUSR, iio_buffer_read_length, iio_buffer_write_length); static struct device_attribute dev_attr_length_ro = __ATTR(length, @@ -1289,12 +1403,20 @@ static struct device_attribute dev_attr_watermark_ro = __ATTR(watermark, S_IRUGO, iio_buffer_show_watermark, NULL); static DEVICE_ATTR(data_available, S_IRUGO, iio_dma_show_data_available, NULL); +static DEVICE_ATTR_RO(direction); +/* + * When adding new attributes here, put the at the end, at least until + * the code that handles the length/length_ro & watermark/watermark_ro + * assignments gets cleaned up. Otherwise these can create some weird + * duplicate attributes errors under some setups. + */ static struct attribute *iio_buffer_attrs[] = { &dev_attr_length.attr, &dev_attr_enable.attr, &dev_attr_watermark.attr, &dev_attr_data_available.attr, + &dev_attr_direction.attr, }; #define to_dev_attr(_attr) container_of(_attr, struct device_attribute, attr) @@ -1397,6 +1519,7 @@ static const struct file_operations iio_buffer_chrdev_fileops = { .owner = THIS_MODULE, .llseek = noop_llseek, .read = iio_buffer_read, + .write = iio_buffer_write, .poll = iio_buffer_poll, .release = iio_buffer_chrdev_release, }; diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c index 2dbb37e09b8c..537a08549a69 100644 --- a/drivers/iio/industrialio-core.c +++ b/drivers/iio/industrialio-core.c @@ -1822,6 +1822,7 @@ static const struct file_operations iio_buffer_fileops = { .owner = THIS_MODULE, .llseek = noop_llseek, .read = iio_buffer_read_outer_addr, + .write = iio_buffer_write_outer_addr, .poll = iio_buffer_poll_addr, .unlocked_ioctl = iio_ioctl, .compat_ioctl = compat_ptr_ioctl, diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h index 451379a3984a..418b1307d3f2 100644 --- a/include/linux/iio/buffer.h +++ b/include/linux/iio/buffer.h @@ -11,8 +11,15 @@ struct iio_buffer; +enum iio_buffer_direction { + IIO_BUFFER_DIRECTION_IN, + IIO_BUFFER_DIRECTION_OUT, +}; + int iio_push_to_buffers(struct iio_dev *indio_dev, const void *data); +int iio_pop_from_buffer(struct iio_buffer *buffer, void *data); + /** * iio_push_to_buffers_with_timestamp() - push data and timestamp to buffers * @indio_dev: iio_dev structure for device. diff --git a/include/linux/iio/buffer_impl.h b/include/linux/iio/buffer_impl.h index 245b32918ae1..e2ca8ea23e19 100644 --- a/include/linux/iio/buffer_impl.h +++ b/include/linux/iio/buffer_impl.h @@ -7,6 +7,7 @@ #ifdef CONFIG_IIO_BUFFER #include <uapi/linux/iio/buffer.h> +#include <linux/iio/buffer.h> struct iio_dev; struct iio_buffer; @@ -23,6 +24,10 @@ struct iio_buffer; * @read: try to get a specified number of bytes (must exist) * @data_available: indicates how much data is available for reading from * the buffer. + * @remove_from: remove scan from buffer. Drivers should calls this to + * remove a scan from a buffer. + * @write: try to write a number of bytes + * @space_available: returns the amount of bytes available in a buffer * @request_update: if a parameter change has been marked, update underlying * storage. * @set_bytes_per_datum:set number of bytes per datum @@ -49,6 +54,9 @@ struct iio_buffer_access_funcs { int (*store_to)(struct iio_buffer *buffer, const void *data); int (*read)(struct iio_buffer *buffer, size_t n, char __user *buf); size_t (*data_available)(struct iio_buffer *buffer); + int (*remove_from)(struct iio_buffer *buffer, void *data); + int (*write)(struct iio_buffer *buffer, size_t n, const char __user *buf); + size_t (*space_available)(struct iio_buffer *buffer); int (*request_update)(struct iio_buffer *buffer); @@ -80,6 +88,9 @@ struct iio_buffer { /** @bytes_per_datum: Size of individual datum including timestamp. */ size_t bytes_per_datum; + /* @direction: Direction of the data stream (in/out). */ + enum iio_buffer_direction direction; + /** * @access: Buffer access functions associated with the * implementation. |