diff options
Diffstat (limited to 'drivers/iio/kfifo_buf.c')
| -rw-r--r-- | drivers/iio/kfifo_buf.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/drivers/iio/kfifo_buf.c b/drivers/iio/kfifo_buf.c index 6bf9d05f484..5bc5c860e9c 100644 --- a/drivers/iio/kfifo_buf.c +++ b/drivers/iio/kfifo_buf.c @@ -6,6 +6,7 @@ #include <linux/kfifo.h> #include <linux/mutex.h> #include <linux/iio/kfifo_buf.h> +#include <linux/sched.h> struct iio_kfifo { struct iio_buffer buffer; @@ -22,7 +23,8 @@ static inline int __iio_allocate_kfifo(struct iio_kfifo *buf, return -EINVAL; __iio_update_buffer(&buf->buffer, bytes_per_datum, length); - return kfifo_alloc(&buf->kf, bytes_per_datum*length, GFP_KERNEL); + return __kfifo_alloc((struct __kfifo *)&buf->kf, length, + bytes_per_datum, GFP_KERNEL); } static int iio_request_update_kfifo(struct iio_buffer *r) @@ -35,6 +37,7 @@ static int iio_request_update_kfifo(struct iio_buffer *r) kfifo_free(&buf->kf); ret = __iio_allocate_kfifo(buf, buf->buffer.bytes_per_datum, buf->buffer.length); + r->stufftoread = false; error_ret: return ret; } @@ -81,6 +84,9 @@ static int iio_set_bytes_per_datum_kfifo(struct iio_buffer *r, size_t bpd) static int iio_set_length_kfifo(struct iio_buffer *r, int length) { + /* Avoid an invalid state */ + if (length < 2) + length = 2; if (r->length != length) { r->length = length; iio_mark_update_needed_kfifo(r); @@ -89,14 +95,16 @@ static int iio_set_length_kfifo(struct iio_buffer *r, int length) } static int iio_store_to_kfifo(struct iio_buffer *r, - u8 *data, - s64 timestamp) + u8 *data) { int ret; struct iio_kfifo *kf = iio_to_kfifo(r); - ret = kfifo_in(&kf->kf, data, r->bytes_per_datum); - if (ret != r->bytes_per_datum) + ret = kfifo_in(&kf->kf, data, 1); + if (ret != 1) return -EBUSY; + r->stufftoread = true; + wake_up_interruptible(&r->pollq); + return 0; } @@ -106,11 +114,18 @@ static int iio_read_first_n_kfifo(struct iio_buffer *r, int ret, copied; struct iio_kfifo *kf = iio_to_kfifo(r); - if (n < r->bytes_per_datum) + if (n < r->bytes_per_datum || r->bytes_per_datum == 0) return -EINVAL; - n = rounddown(n, r->bytes_per_datum); ret = kfifo_to_user(&kf->kf, buf, n, &copied); + if (ret < 0) + return ret; + + if (kfifo_is_empty(&kf->kf)) + r->stufftoread = false; + /* verify it is still empty to avoid race */ + if (!kfifo_is_empty(&kf->kf)) + r->stufftoread = true; return copied; } @@ -136,7 +151,7 @@ struct iio_buffer *iio_kfifo_allocate(struct iio_dev *indio_dev) iio_buffer_init(&kf->buffer); kf->buffer.attrs = &iio_kfifo_attribute_group; kf->buffer.access = &kfifo_access_funcs; - + kf->buffer.length = 2; return &kf->buffer; } EXPORT_SYMBOL(iio_kfifo_allocate); |