Merge "i2c: virtio:refine the driver of i2c virtualization" (7d23ad2b) · Commits · e / devices / android_kernel_oneplus_sm8150

drivers/i2c/busses/virtio-i2c.c

+44 −59

Original line number	Diff line number	Diff line
		@@ -34,19 +34,6 @@
		#define I2C_VIRTIO_WR 0x02
		#define I2C_VIRTIO_RDWR 0x03

		/**
		* struct virtio_i2c - virtio i2c device
		* @adapter: i2c adapter
		* @vdev: the virtio device
		* @vq: i2c virtqueue
		*/
		struct virtio_i2c {
		struct i2c_adapter adapter;
		struct virtio_device *vdev;
		struct virtqueue *vq;
		wait_queue_head_t inq;
		};

		struct i2c_transfer_head {
		u32 type; /* read or write from or to slave */
		u32 addr; /* slave addr */
		@@ -64,6 +51,21 @@ struct virtio_i2c_req {
		struct i2c_transfer_end end;
		};

		/**
		* struct virtio_i2c - virtio i2c device
		* @adapter: i2c adapter
		* @vdev: the virtio device
		* @i2c_req: description of the fromat of transfer data
		* @vq: i2c virtqueue
		*/
		struct virtio_i2c {
		struct i2c_adapter adapter;
		struct virtio_device *vdev;
		struct virtio_i2c_req i2c_req;
		struct virtqueue *vq;
		wait_queue_head_t inq;
		};

		static int virti2c_transfer(struct virtio_i2c *vi2c,
		struct virtio_i2c_req *i2c_req)
		{
		@@ -117,49 +119,35 @@ static int virti2c_transfer(struct virtio_i2c *vi2c,
		}

		/* prepare the transfer req */
		static struct virtio_i2c_req virti2c_transfer_prepare(struct i2c_msg msg_1,
		struct i2c_msg *msg_2)
		static int virti2c_transfer_prepare(struct i2c_msg *msg_1,
		struct i2c_msg msg_2, struct virtio_i2c_req i2c_req)
		{
		char *ptr = NULL;
		int merge = 0;
		struct virtio_i2c_req *i2c_req;

		if (msg_1 == NULL)
		return NULL;

		if (msg_2)
		merge = 1;

		i2c_req = kzalloc(sizeof(struct virtio_i2c_req), GFP_KERNEL);
		if (i2c_req == NULL)
		return NULL;
		if (IS_ERR_OR_NULL(msg_1) \|\| !msg_1->len \|\|
		IS_ERR_OR_NULL(msg_1->buf))
		return -EINVAL;

		if (merge)
		ptr = kzalloc((msg_1->len + msg_2->len), GFP_KERNEL);
		else
		ptr = msg_1->buf;
		if (ptr == NULL)
		goto err_mem;

		/* prepare the head */
		i2c_req->head.type = merge ?
		I2C_VIRTIO_RDWR : ((msg_1->flags & I2C_M_RD) ?
		I2C_VIRTIO_RD : I2C_VIRTIO_WR);
		i2c_req->head.addr = msg_1->addr;
		i2c_req->head.length = msg_1->len;
		if (merge)

		if (IS_ERR_OR_NULL(msg_2)) {
		i2c_req->head.type = (msg_1->flags & I2C_M_RD) ?
		I2C_VIRTIO_RD : I2C_VIRTIO_WR;
		i2c_req->buf = msg_1->buf;
		} else {
		if (!msg_2->len \|\| IS_ERR_OR_NULL(msg_2->buf))
		return -EINVAL;

		i2c_req->head.type = I2C_VIRTIO_RDWR;
		i2c_req->head.total_length = msg_1->len + msg_2->len;

		/* prepare the buf */
		if (merge)
		memcpy(ptr, msg_1->buf, msg_1->len);
		i2c_req->buf = ptr;
		i2c_req->buf = kzalloc((msg_1->len + msg_2->len), GFP_KERNEL);
		if (IS_ERR_OR_NULL(i2c_req->buf))
		return -ENOMEM;

		memcpy(i2c_req->buf, msg_1->buf, msg_1->len);
		}

		return i2c_req;
		err_mem:
		kfree(i2c_req);
		i2c_req = NULL;
		return NULL;
		return 0;
		}

		static void virti2c_transfer_end(struct virtio_i2c_req *req,
		@@ -171,16 +159,15 @@ static void virti2c_transfer_end(struct virtio_i2c_req *req,
		req->buf = NULL;
		}

		kfree(req);
		req = NULL;
		memset(req, 0, sizeof(struct virtio_i2c_req));
		}

		static int virtio_i2c_master_xfer(struct i2c_adapter *adap,
		struct i2c_msg *msgs, int num)
		{
		int i, ret;
		struct virtio_i2c_req *i2c_req;
		struct virtio_i2c *vi2c = i2c_get_adapdata(adap);
		struct virtio_i2c_req *i2c_req = &vi2c->i2c_req;

		if (num < 1) {
		dev_err(&vi2c->vdev->dev,
		@@ -197,24 +184,22 @@ static int virtio_i2c_master_xfer(struct i2c_adapter *adap,

		if (msgs[i].flags & I2C_M_RD) {
		/* read the data from slave to master*/
		i2c_req = virti2c_transfer_prepare(&msgs[i], NULL);
		ret = virti2c_transfer_prepare(&msgs[i], NULL, i2c_req);

		} else if ((i + 1 < num) && (msgs[i + 1].flags & I2C_M_RD) &&
		(msgs[i].addr == msgs[i + 1].addr)) {
		/* write then read from same address*/
		i2c_req = virti2c_transfer_prepare(&msgs[i],
		&msgs[i+1]);
		ret = virti2c_transfer_prepare(&msgs[i],
		&msgs[i+1], i2c_req);
		i += 1;

		} else {
		/* write the data to slave */
		i2c_req = virti2c_transfer_prepare(&msgs[i], NULL);
		ret = virti2c_transfer_prepare(&msgs[i], NULL, i2c_req);
		}

		if (i2c_req == NULL) {
		ret = -ENOMEM;
		if (ret)
		goto err;
		}
		ret = virti2c_transfer(vi2c, i2c_req);
		virti2c_transfer_end(i2c_req, &msgs[i]);
		if (ret)