Add bridged amplifiers to cs42l43

Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>:

In some cs42l43 systems a couple of cs35l56 amplifiers are attached
to the cs42l43's SPI and I2S. On Windows the cs42l43 is controlled
by a SDCA class driver and these two amplifiers are controlled by
firmware running on the cs42l43. However, under Linux the decision
was made to interact with the cs42l43 directly, affording the user
greater control over the audio system. However, this has resulted
in an issue where these two bridged cs35l56 amplifiers are not
populated in ACPI and must be added manually. There is at least an
SDCA extension unit DT entry we can key off.

The process of adding this is handled using a software node, firstly the
ability to add native chip selects to software nodes must be added.
Secondly, an additional flag for naming the SPI devices is added this
allows the machine driver to key to the correct amplifier. Then finally,
the cs42l43 SPI driver adds the two amplifiers directly onto its SPI
bus.

An additional series will follow soon to add the audio machine driver
parts (in the sof-sdw driver), however that is fairly orthogonal to
this part of the process, getting the actual amplifiers registered.

1 files changed, 19 insertions, 12 deletions

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 5d4b448fdc50..4521c2b66b98 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -147,6 +147,7 @@ static bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
 static void io_queue_sqe(struct io_kiocb *req);
 
 struct kmem_cache *req_cachep;
+static struct workqueue_struct *iou_wq __ro_after_init;
 
 static int __read_mostly sysctl_io_uring_disabled;
 static int __read_mostly sysctl_io_uring_group = -1;
@@ -350,7 +351,6 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
 err:
 	kfree(ctx->cancel_table.hbs);
 	kfree(ctx->cancel_table_locked.hbs);
-	kfree(ctx->io_bl);
 	xa_destroy(&ctx->io_bl_xa);
 	kfree(ctx);
 	return NULL;
@@ -1982,10 +1982,15 @@ fail:
 		err = -EBADFD;
 		if (!io_file_can_poll(req))
 			goto fail;
-		err = -ECANCELED;
-		if (io_arm_poll_handler(req, issue_flags) != IO_APOLL_OK)
-			goto fail;
-		return;
+		if (req->file->f_flags & O_NONBLOCK ||
+		    req->file->f_mode & FMODE_NOWAIT) {
+			err = -ECANCELED;
+			if (io_arm_poll_handler(req, issue_flags) != IO_APOLL_OK)
+				goto fail;
+			return;
+		} else {
+			req->flags &= ~REQ_F_APOLL_MULTISHOT;
+		}
 	}
 
 	if (req->flags & REQ_F_FORCE_ASYNC) {
@@ -2926,7 +2931,6 @@ static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx)
 	io_napi_free(ctx);
 	kfree(ctx->cancel_table.hbs);
 	kfree(ctx->cancel_table_locked.hbs);
-	kfree(ctx->io_bl);
 	xa_destroy(&ctx->io_bl_xa);
 	kfree(ctx);
 }
@@ -3161,7 +3165,7 @@ static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
 	 * noise and overhead, there's no discernable change in runtime
 	 * over using system_wq.
 	 */
-	queue_work(system_unbound_wq, &ctx->exit_work);
+	queue_work(iou_wq, &ctx->exit_work);
 }
 
 static int io_uring_release(struct inode *inode, struct file *file)
@@ -3443,14 +3447,15 @@ static void *io_uring_validate_mmap_request(struct file *file,
 		ptr = ctx->sq_sqes;
 		break;
 	case IORING_OFF_PBUF_RING: {
+		struct io_buffer_list *bl;
 		unsigned int bgid;
 
 		bgid = (offset & ~IORING_OFF_MMAP_MASK) >> IORING_OFF_PBUF_SHIFT;
-		rcu_read_lock();
-		ptr = io_pbuf_get_address(ctx, bgid);
-		rcu_read_unlock();
-		if (!ptr)
-			return ERR_PTR(-EINVAL);
+		bl = io_pbuf_get_bl(ctx, bgid);
+		if (IS_ERR(bl))
+			return bl;
+		ptr = bl->buf_ring;
+		io_put_bl(ctx, bl);
 		break;
 		}
 	default:
@@ -4185,6 +4190,8 @@ static int __init io_uring_init(void)
 	io_buf_cachep = KMEM_CACHE(io_buffer,
 					  SLAB_HWCACHE_ALIGN | SLAB_PANIC | SLAB_ACCOUNT);
 
+	iou_wq = alloc_workqueue("iou_exit", WQ_UNBOUND, 64);
+
 #ifdef CONFIG_SYSCTL
 	register_sysctl_init("kernel", kernel_io_uring_disabled_table);
 #endif