Commit 19324328 authored by Greg Kroah-Hartman's avatar Greg Kroah-Hartman
Browse files

Merge branch 'work-next' into staging-next

parents 5f070a36 a1e44d6a

drivers/staging/iio/ring_sw.c

+23 −35
Original line number Diff line number Diff line
@@ -170,6 +170,7 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r, 
	u8 *initial_read_p, *initial_write_p, *current_read_p, *end_read_p;

	u8 *data;

	int ret, max_copied, bytes_to_rip, dead_offset;

	size_t data_available, buffer_size;



	/* A userspace program has probably made an error if it tries to

	 *  read something that is not a whole number of bpds.
@@ -182,9 +183,11 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r, 
		       n, ring->buf.bytes_per_datum);

		goto error_ret;

	}



	buffer_size = ring->buf.bytes_per_datum*ring->buf.length;



	/* Limit size to whole of ring buffer */

	bytes_to_rip = min((size_t)(ring->buf.bytes_per_datum*ring->buf.length),

			   n);

	bytes_to_rip = min_t(size_t, buffer_size, n);



	data = kmalloc(bytes_to_rip, GFP_KERNEL);

	if (data == NULL) {
@@ -213,38 +216,24 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r, 
		goto error_free_data_cpy;

	}



	if (initial_write_p >= initial_read_p + bytes_to_rip) {

		/* write_p is greater than necessary, all is easy */

		max_copied = bytes_to_rip;

		memcpy(data, initial_read_p, max_copied);

		end_read_p = initial_read_p + max_copied;

	} else if (initial_write_p > initial_read_p) {

		/*not enough data to cpy */

		max_copied = initial_write_p - initial_read_p;

	if (initial_write_p >= initial_read_p)

		data_available = initial_write_p - initial_read_p;

	else

		data_available = buffer_size - (initial_read_p - initial_write_p);



	if (data_available < bytes_to_rip)

		bytes_to_rip = data_available;



	if (initial_read_p + bytes_to_rip >= ring->data + buffer_size) {

		max_copied = ring->data + buffer_size - initial_read_p;

		memcpy(data, initial_read_p, max_copied);

		end_read_p = initial_write_p;

		memcpy(data + max_copied, ring->data, bytes_to_rip - max_copied);

		end_read_p = ring->data + bytes_to_rip - max_copied;

	} else {

		/* going through 'end' of ring buffer */

		max_copied = ring->data

			+ ring->buf.length*ring->buf.bytes_per_datum - initial_read_p;

		memcpy(data, initial_read_p, max_copied);

		/* possible we are done if we align precisely with end */

		if (max_copied == bytes_to_rip)

			end_read_p = ring->data;

		else if (initial_write_p

			 > ring->data + bytes_to_rip - max_copied) {

			/* enough data to finish */

			memcpy(data + max_copied, ring->data,

			       bytes_to_rip - max_copied);

			max_copied = bytes_to_rip;

			end_read_p = ring->data + (bytes_to_rip - max_copied);

		} else {  /* not enough data */

			memcpy(data + max_copied, ring->data,

			       initial_write_p - ring->data);

			max_copied += initial_write_p - ring->data;

			end_read_p = initial_write_p;

		}

		memcpy(data, initial_read_p, bytes_to_rip);

		end_read_p = initial_read_p + bytes_to_rip;

	}



	/* Now to verify which section was cleanly copied - i.e. how far

	 * read pointer has been pushed */

	current_read_p = ring->read_p;
@@ -252,15 +241,14 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r, 
	if (initial_read_p <= current_read_p)

		dead_offset = current_read_p - initial_read_p;

	else

		dead_offset = ring->buf.length*ring->buf.bytes_per_datum

			- (initial_read_p - current_read_p);

		dead_offset = buffer_size - (initial_read_p - current_read_p);



	/* possible issue if the initial write has been lapped or indeed

	 * the point we were reading to has been passed */

	/* No valid data read.

	 * In this case the read pointer is already correct having been

	 * pushed further than we would look. */

	if (max_copied - dead_offset < 0) {

	if (bytes_to_rip - dead_offset < 0) {

		ret = 0;

		goto error_free_data_cpy;

	}
@@ -276,7 +264,7 @@ static int iio_read_first_n_sw_rb(struct iio_buffer *r, 
	while (ring->read_p != end_read_p)

		ring->read_p = end_read_p;



	ret = max_copied - dead_offset;

	ret = bytes_to_rip - dead_offset;



	if (copy_to_user(buf, data + dead_offset, ret))  {

		ret =  -EFAULT;

drivers/staging/iio/types.h

+1 −1
Original line number Diff line number Diff line
@@ -35,7 +35,7 @@ enum iio_modifier { 
	IIO_MOD_Y,

	IIO_MOD_Z,

	IIO_MOD_X_AND_Y,

	IIO_MOD_X_ANX_Z,

	IIO_MOD_X_AND_Z,

	IIO_MOD_Y_AND_Z,

	IIO_MOD_X_AND_Y_AND_Z,

	IIO_MOD_X_OR_Y,