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authorLinus Torvalds <torvalds@linux-foundation.org>2021-11-03 15:00:39 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2021-11-03 15:00:39 -0700
commit43e1b12927276cde8052122a24ff796649f09d60 (patch)
treee1629f35aca8b865691932bea03d51517926acb0 /drivers/i2c
parentd4ec3d5535c784c3adbc41c2bbc5d17a00a4a898 (diff)
parent540061ac79f0302ae91e44e6cd216cbaa3af1757 (diff)
downloadlinux-43e1b12927276cde8052122a24ff796649f09d60.tar.gz
Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Pull virtio updates from Michael Tsirkin:
 "vhost and virtio fixes and features:

   - Hardening work by Jason

   - vdpa driver for Alibaba ENI

   - Performance tweaks for virtio blk

   - virtio rng rework using an internal buffer

   - mac/mtu programming for mlx5 vdpa

   - Misc fixes, cleanups"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (45 commits)
  vdpa/mlx5: Forward only packets with allowed MAC address
  vdpa/mlx5: Support configuration of MAC
  vdpa/mlx5: Fix clearing of VIRTIO_NET_F_MAC feature bit
  vdpa_sim_net: Enable user to set mac address and mtu
  vdpa: Enable user to set mac and mtu of vdpa device
  vdpa: Use kernel coding style for structure comments
  vdpa: Introduce query of device config layout
  vdpa: Introduce and use vdpa device get, set config helpers
  virtio-scsi: don't let virtio core to validate used buffer length
  virtio-blk: don't let virtio core to validate used length
  virtio-net: don't let virtio core to validate used length
  virtio_ring: validate used buffer length
  virtio_blk: correct types for status handling
  virtio_blk: allow 0 as num_request_queues
  i2c: virtio: Add support for zero-length requests
  virtio-blk: fixup coccinelle warnings
  virtio_ring: fix typos in vring_desc_extra
  virtio-pci: harden INTX interrupts
  virtio_pci: harden MSI-X interrupts
  virtio_config: introduce a new .enable_cbs method
  ...
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-virtio.c56
1 files changed, 30 insertions, 26 deletions
diff --git a/drivers/i2c/busses/i2c-virtio.c b/drivers/i2c/busses/i2c-virtio.c
index f10a603b13fb..1ed4daa918a0 100644
--- a/drivers/i2c/busses/i2c-virtio.c
+++ b/drivers/i2c/busses/i2c-virtio.c
@@ -63,34 +63,32 @@ static int virtio_i2c_prepare_reqs(struct virtqueue *vq,
 		int outcnt = 0, incnt = 0;
 
 		/*
-		 * We don't support 0 length messages and so filter out
-		 * 0 length transfers by using i2c_adapter_quirks.
-		 */
-		if (!msgs[i].len)
-			break;
-
-		/*
 		 * Only 7-bit mode supported for this moment. For the address
 		 * format, Please check the Virtio I2C Specification.
 		 */
 		reqs[i].out_hdr.addr = cpu_to_le16(msgs[i].addr << 1);
 
+		if (msgs[i].flags & I2C_M_RD)
+			reqs[i].out_hdr.flags |= cpu_to_le32(VIRTIO_I2C_FLAGS_M_RD);
+
 		if (i != num - 1)
-			reqs[i].out_hdr.flags = cpu_to_le32(VIRTIO_I2C_FLAGS_FAIL_NEXT);
+			reqs[i].out_hdr.flags |= cpu_to_le32(VIRTIO_I2C_FLAGS_FAIL_NEXT);
 
 		sg_init_one(&out_hdr, &reqs[i].out_hdr, sizeof(reqs[i].out_hdr));
 		sgs[outcnt++] = &out_hdr;
 
-		reqs[i].buf = i2c_get_dma_safe_msg_buf(&msgs[i], 1);
-		if (!reqs[i].buf)
-			break;
+		if (msgs[i].len) {
+			reqs[i].buf = i2c_get_dma_safe_msg_buf(&msgs[i], 1);
+			if (!reqs[i].buf)
+				break;
 
-		sg_init_one(&msg_buf, reqs[i].buf, msgs[i].len);
+			sg_init_one(&msg_buf, reqs[i].buf, msgs[i].len);
 
-		if (msgs[i].flags & I2C_M_RD)
-			sgs[outcnt + incnt++] = &msg_buf;
-		else
-			sgs[outcnt++] = &msg_buf;
+			if (msgs[i].flags & I2C_M_RD)
+				sgs[outcnt + incnt++] = &msg_buf;
+			else
+				sgs[outcnt++] = &msg_buf;
+		}
 
 		sg_init_one(&in_hdr, &reqs[i].in_hdr, sizeof(reqs[i].in_hdr));
 		sgs[outcnt + incnt++] = &in_hdr;
@@ -191,7 +189,7 @@ static int virtio_i2c_setup_vqs(struct virtio_i2c *vi)
 
 static u32 virtio_i2c_func(struct i2c_adapter *adap)
 {
-	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
 }
 
 static struct i2c_algorithm virtio_algorithm = {
@@ -199,15 +197,16 @@ static struct i2c_algorithm virtio_algorithm = {
 	.functionality = virtio_i2c_func,
 };
 
-static const struct i2c_adapter_quirks virtio_i2c_quirks = {
-	.flags = I2C_AQ_NO_ZERO_LEN,
-};
-
 static int virtio_i2c_probe(struct virtio_device *vdev)
 {
 	struct virtio_i2c *vi;
 	int ret;
 
+	if (!virtio_has_feature(vdev, VIRTIO_I2C_F_ZERO_LENGTH_REQUEST)) {
+		dev_err(&vdev->dev, "Zero-length request feature is mandatory\n");
+		return -EINVAL;
+	}
+
 	vi = devm_kzalloc(&vdev->dev, sizeof(*vi), GFP_KERNEL);
 	if (!vi)
 		return -ENOMEM;
@@ -225,7 +224,6 @@ static int virtio_i2c_probe(struct virtio_device *vdev)
 	snprintf(vi->adap.name, sizeof(vi->adap.name),
 		 "i2c_virtio at virtio bus %d", vdev->index);
 	vi->adap.algo = &virtio_algorithm;
-	vi->adap.quirks = &virtio_i2c_quirks;
 	vi->adap.dev.parent = &vdev->dev;
 	vi->adap.dev.of_node = vdev->dev.of_node;
 	i2c_set_adapdata(&vi->adap, vi);
@@ -270,11 +268,17 @@ static int virtio_i2c_restore(struct virtio_device *vdev)
 }
 #endif
 
+static const unsigned int features[] = {
+	VIRTIO_I2C_F_ZERO_LENGTH_REQUEST,
+};
+
 static struct virtio_driver virtio_i2c_driver = {
-	.id_table	= id_table,
-	.probe		= virtio_i2c_probe,
-	.remove		= virtio_i2c_remove,
-	.driver	= {
+	.feature_table		= features,
+	.feature_table_size	= ARRAY_SIZE(features),
+	.id_table		= id_table,
+	.probe			= virtio_i2c_probe,
+	.remove			= virtio_i2c_remove,
+	.driver			= {
 		.name	= "i2c_virtio",
 	},
 #ifdef CONFIG_PM_SLEEP