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authorLinus Torvalds <torvalds@linux-foundation.org>2012-05-22 16:34:21 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-05-22 16:34:21 -0700
commitfb09bafda67041b74a668dc9d77735e36bd33d3b (patch)
tree2dd32b65062a95045468fdcab366ecdb8e4fcac6 /drivers/iio/kfifo_buf.c
parent94b5aff4c6f72fee6b0f49d49e4fa8b204e8ded9 (diff)
parentc3c6cc91b0ae7b3d598488ad0b593bafba4a0817 (diff)
Merge tag 'staging-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging
Pull staging tree changes from Greg Kroah-Hartman: "Here is the big staging tree pull request for the 3.5-rc1 merge window. Loads of changes here, and we just narrowly added more lines than we added: 622 files changed, 28356 insertions(+), 26059 deletions(-) But, good news is that there is a number of subsystems that moved out of the staging tree, to their respective "real" portions of the kernel. Code that moved out was: - iio core code - mei driver - vme core and bridge drivers There was one broken network driver that moved into staging as a step before it is removed from the tree (pc300), and there was a few new drivers added to the tree: - new iio drivers - gdm72xx wimax USB driver - ipack subsystem and 2 drivers All of the movements around have acks from the various subsystem maintainers, and all of this has been in the linux-next tree for a while. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>" Fixed up various trivial conflicts, along with a non-trivial one found in -next and pointed out by Olof Johanssen: a clean - but incorrect - merge of the arch/arm/boot/dts/at91sam9g20.dtsi file. Fix up manually as per Stephen Rothwell. * tag 'staging-3.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging: (536 commits) Staging: bcm: Remove two unused variables from Adapter.h Staging: bcm: Removes the volatile type definition from Adapter.h Staging: bcm: Rename all "INT" to "int" in Adapter.h Staging: bcm: Fix warning: __packed vs. __attribute__((packed)) in Adapter.h Staging: bcm: Correctly format all comments in Adapter.h Staging: bcm: Fix all whitespace issues in Adapter.h Staging: bcm: Properly format braces in Adapter.h Staging: ipack/bridges/tpci200: remove unneeded casts Staging: ipack/bridges/tpci200: remove TPCI200_SHORTNAME constant Staging: ipack: remove board_name and bus_name fields from struct ipack_device Staging: ipack: improve the register of a bus and a device in the bus. staging: comedi: cleanup all the comedi_driver 'detach' functions staging: comedi: remove all 'default N' in Kconfig staging: line6/config.h: Delete unused header staging: gdm72xx depends on NET staging: gdm72xx: Set up parent link in sysfs for gdm72xx devices staging: drm/omap: initial dmabuf/prime import support staging: drm/omap: dmabuf/prime mmap support pstore/ram: Add ECC support pstore/ram: Switch to persistent_ram routines ...
Diffstat (limited to 'drivers/iio/kfifo_buf.c')
-rw-r--r--drivers/iio/kfifo_buf.c150
1 files changed, 150 insertions, 0 deletions
diff --git a/drivers/iio/kfifo_buf.c b/drivers/iio/kfifo_buf.c
new file mode 100644
index 000000000000..6bf9d05f4841
--- /dev/null
+++ b/drivers/iio/kfifo_buf.c
@@ -0,0 +1,150 @@
+#include <linux/slab.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/workqueue.h>
+#include <linux/kfifo.h>
+#include <linux/mutex.h>
+#include <linux/iio/kfifo_buf.h>
+
+struct iio_kfifo {
+ struct iio_buffer buffer;
+ struct kfifo kf;
+ int update_needed;
+};
+
+#define iio_to_kfifo(r) container_of(r, struct iio_kfifo, buffer)
+
+static inline int __iio_allocate_kfifo(struct iio_kfifo *buf,
+ int bytes_per_datum, int length)
+{
+ if ((length == 0) || (bytes_per_datum == 0))
+ return -EINVAL;
+
+ __iio_update_buffer(&buf->buffer, bytes_per_datum, length);
+ return kfifo_alloc(&buf->kf, bytes_per_datum*length, GFP_KERNEL);
+}
+
+static int iio_request_update_kfifo(struct iio_buffer *r)
+{
+ int ret = 0;
+ struct iio_kfifo *buf = iio_to_kfifo(r);
+
+ if (!buf->update_needed)
+ goto error_ret;
+ kfifo_free(&buf->kf);
+ ret = __iio_allocate_kfifo(buf, buf->buffer.bytes_per_datum,
+ buf->buffer.length);
+error_ret:
+ return ret;
+}
+
+static int iio_get_length_kfifo(struct iio_buffer *r)
+{
+ return r->length;
+}
+
+static IIO_BUFFER_ENABLE_ATTR;
+static IIO_BUFFER_LENGTH_ATTR;
+
+static struct attribute *iio_kfifo_attributes[] = {
+ &dev_attr_length.attr,
+ &dev_attr_enable.attr,
+ NULL,
+};
+
+static struct attribute_group iio_kfifo_attribute_group = {
+ .attrs = iio_kfifo_attributes,
+ .name = "buffer",
+};
+
+static int iio_get_bytes_per_datum_kfifo(struct iio_buffer *r)
+{
+ return r->bytes_per_datum;
+}
+
+static int iio_mark_update_needed_kfifo(struct iio_buffer *r)
+{
+ struct iio_kfifo *kf = iio_to_kfifo(r);
+ kf->update_needed = true;
+ return 0;
+}
+
+static int iio_set_bytes_per_datum_kfifo(struct iio_buffer *r, size_t bpd)
+{
+ if (r->bytes_per_datum != bpd) {
+ r->bytes_per_datum = bpd;
+ iio_mark_update_needed_kfifo(r);
+ }
+ return 0;
+}
+
+static int iio_set_length_kfifo(struct iio_buffer *r, int length)
+{
+ if (r->length != length) {
+ r->length = length;
+ iio_mark_update_needed_kfifo(r);
+ }
+ return 0;
+}
+
+static int iio_store_to_kfifo(struct iio_buffer *r,
+ u8 *data,
+ s64 timestamp)
+{
+ 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)
+ return -EBUSY;
+ return 0;
+}
+
+static int iio_read_first_n_kfifo(struct iio_buffer *r,
+ size_t n, char __user *buf)
+{
+ int ret, copied;
+ struct iio_kfifo *kf = iio_to_kfifo(r);
+
+ if (n < r->bytes_per_datum)
+ return -EINVAL;
+
+ n = rounddown(n, r->bytes_per_datum);
+ ret = kfifo_to_user(&kf->kf, buf, n, &copied);
+
+ return copied;
+}
+
+static const struct iio_buffer_access_funcs kfifo_access_funcs = {
+ .store_to = &iio_store_to_kfifo,
+ .read_first_n = &iio_read_first_n_kfifo,
+ .request_update = &iio_request_update_kfifo,
+ .get_bytes_per_datum = &iio_get_bytes_per_datum_kfifo,
+ .set_bytes_per_datum = &iio_set_bytes_per_datum_kfifo,
+ .get_length = &iio_get_length_kfifo,
+ .set_length = &iio_set_length_kfifo,
+};
+
+struct iio_buffer *iio_kfifo_allocate(struct iio_dev *indio_dev)
+{
+ struct iio_kfifo *kf;
+
+ kf = kzalloc(sizeof *kf, GFP_KERNEL);
+ if (!kf)
+ return NULL;
+ kf->update_needed = true;
+ iio_buffer_init(&kf->buffer);
+ kf->buffer.attrs = &iio_kfifo_attribute_group;
+ kf->buffer.access = &kfifo_access_funcs;
+
+ return &kf->buffer;
+}
+EXPORT_SYMBOL(iio_kfifo_allocate);
+
+void iio_kfifo_free(struct iio_buffer *r)
+{
+ kfree(iio_to_kfifo(r));
+}
+EXPORT_SYMBOL(iio_kfifo_free);
+
+MODULE_LICENSE("GPL");