On Fri, Jul 02, 2021 at 04:46:47PM +0800, Jie Deng wrote: > Add an I2C bus driver for virtio para-virtualization. > > The controller can be emulated by the backend driver in > any device model software by following the virtio protocol. > > The device specification can be found on > https://lists.oasis-open.org/archives/virtio-comment/202101/msg00008.html. > > By following the specification, people may implement different > backend drivers to emulate different controllers according to > their needs. ... > +static int virtio_i2c_complete_reqs(struct virtqueue *vq, > + struct virtio_i2c_req *reqs, > + struct i2c_msg *msgs, int nr, > + bool fail) > +{ > + struct virtio_i2c_req *req; > + bool failed = fail; > + unsigned int len; > + int i, j = 0; > + > + for (i = 0; i < nr; i++) { > + /* Detach the ith request from the vq */ > + req = virtqueue_get_buf(vq, &len); > + > + /* > + * Condition (req && req == &reqs[i]) should always meet since > + * we have total nr requests in the vq. > + */ > + if (!failed && (WARN_ON(!(req && req == &reqs[i])) || > + (req->in_hdr.status != VIRTIO_I2C_MSG_OK))) > + failed = true; ...and after failed is true, we are continuing the loop, why? > + i2c_put_dma_safe_msg_buf(reqs[i].buf, &msgs[i], !failed); > + if (!failed) > + ++j; Besides better to read j++ the j itself can be renamed to something more verbose. > + } > + return (fail ? -ETIMEDOUT : j); Redundant parentheses. > +} ... > + ret = virtio_i2c_send_reqs(vq, reqs, msgs, num); > + if (ret != num) { > + virtio_i2c_complete_reqs(vq, reqs, msgs, ret, true); Below you check the returned code, here is not. > + ret = 0; > + goto err_free; > + } > + > + reinit_completion(&vi->completion); > + virtqueue_kick(vq); > + > + time_left = wait_for_completion_timeout(&vi->completion, adap->timeout); > + if (!time_left) > + dev_err(&adap->dev, "virtio i2c backend timeout.\n"); > + > + ret = virtio_i2c_complete_reqs(vq, reqs, msgs, num, !time_left); > + > +err_free: > + kfree(reqs); > + return ret; > +++ b/include/uapi/linux/virtio_i2c.h > +#include <linux/types.h> > + > +/* The bit 0 of the @virtio_i2c_out_hdr.@flags, used to group the requests */ > +#define VIRTIO_I2C_FLAGS_FAIL_NEXT BIT(0) It's _BITUL() or so from linux/const.h. https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/const.h#L28 You may not use internal definitions in UAPI headers. -- With Best Regards, Andy Shevchenko _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
