ASoC: wm8904: Add DMIC and DRC support

Merge series from Francesco Dolcini <francesco@dolcini.it>:

This patch series adds DMIC and DRC support to the WM8904 driver, a new
of_ helper is added to simplify the driver code.

DRC functionality is added in the same patch series to provide the
necessary dynamic range control to make DMIC support useful.

The WM8904 supports digital microphones on two of its inputs:
IN1L/DMICDAT1 and IN1R/DMICDAT2. These two inputs can either be
connected to an ADC or to the DMIC system. There is an ADC for each
line, and only one DMIC block. This DMIC block is either connected to
DMICDAT1 or to DMICDAT2. One DMIC data line supports two digital
microphones via time multiplexing.

The pin's functionality is decided during hardware design (IN1L vs
DMICDAT1 and IN1R vs DMICDAT2). This is reflected in the Device Tree.

If one line is analog and one is DMIC, we need to be able to switch
between ADC and DMIC at runtime. The DMIC source is known from the
Device Tree. If both are DMIC inputs, we need to be able to switch the
DMIC source. There is no need to switch between ADC and DMIC at runtime.

Therefore, kcontrols are dynamically added by the driver depending on
its Device Tree configuration.

This is a heavy rework of a previous patch series provided by Alifer
Moraes and Pierluigi Passaro,
https://lore.kernel.org/lkml/20220307141041.27538-1-alifer.m@variscite.com.

12 files changed, 132 insertions, 34 deletions

diff --git a/include/linux/blk-mq.h b/include/linux/blk-mq.h
index fa2a76cc2f73..aba9c24486aa 100644
--- a/include/linux/blk-mq.h
+++ b/include/linux/blk-mq.h
@@ -28,7 +28,7 @@ typedef enum rq_end_io_ret (rq_end_io_fn)(struct request *, blk_status_t);
 typedef __u32 __bitwise req_flags_t;
 
 /* Keep rqf_name[] in sync with the definitions below */
-enum {
+enum rqf_flags {
 	/* drive already may have started this one */
 	__RQF_STARTED,
 	/* request for flush sequence */
@@ -852,12 +852,20 @@ static inline bool blk_mq_is_reserved_rq(struct request *rq)
 	return rq->rq_flags & RQF_RESV;
 }
 
-/*
+/**
+ * blk_mq_add_to_batch() - add a request to the completion batch
+ * @req: The request to add to batch
+ * @iob: The batch to add the request
+ * @is_error: Specify true if the request failed with an error
+ * @complete: The completaion handler for the request
+ *
  * Batched completions only work when there is no I/O error and no special
  * ->end_io handler.
+ *
+ * Return: true when the request was added to the batch, otherwise false
  */
 static inline bool blk_mq_add_to_batch(struct request *req,
-				       struct io_comp_batch *iob, int ioerror,
+				       struct io_comp_batch *iob, bool is_error,
 				       void (*complete)(struct io_comp_batch *))
 {
 	/*
@@ -865,7 +873,7 @@ static inline bool blk_mq_add_to_batch(struct request *req,
 	 * 1) No batch container
 	 * 2) Has scheduler data attached
 	 * 3) Not a passthrough request and end_io set
-	 * 4) Not a passthrough request and an ioerror
+	 * 4) Not a passthrough request and failed with an error
 	 */
 	if (!iob)
 		return false;
@@ -874,7 +882,7 @@ static inline bool blk_mq_add_to_batch(struct request *req,
 	if (!blk_rq_is_passthrough(req)) {
 		if (req->end_io)
 			return false;
-		if (ioerror < 0)
+		if (is_error)
 			return false;
 	}
 
diff --git a/include/linux/cleanup.h b/include/linux/cleanup.h
index ec00e3f7af2b..ee2614adb785 100644
--- a/include/linux/cleanup.h
+++ b/include/linux/cleanup.h
@@ -212,7 +212,7 @@ const volatile void * __must_check_fn(const volatile void *val)
 { return val; }
 
 #define no_free_ptr(p) \
-	((typeof(p)) __must_check_fn(__get_and_null(p, NULL)))
+	((typeof(p)) __must_check_fn((__force const volatile void *)__get_and_null(p, NULL)))
 
 #define return_ptr(p)	return no_free_ptr(p)
 
diff --git a/include/linux/compaction.h b/include/linux/compaction.h
index e94776496049..7bf0c521db63 100644
--- a/include/linux/compaction.h
+++ b/include/linux/compaction.h
@@ -80,6 +80,11 @@ static inline unsigned long compact_gap(unsigned int order)
 	return 2UL << order;
 }
 
+static inline int current_is_kcompactd(void)
+{
+	return current->flags & PF_KCOMPACTD;
+}
+
 #ifdef CONFIG_COMPACTION
 
 extern unsigned int extfrag_for_order(struct zone *zone, unsigned int order);
diff --git a/include/linux/cred.h b/include/linux/cred.h
index 0c3c4b16b469..5658a3bfe803 100644
--- a/include/linux/cred.h
+++ b/include/linux/cred.h
@@ -172,18 +172,12 @@ static inline bool cap_ambient_invariant_ok(const struct cred *cred)
 
 static inline const struct cred *override_creds(const struct cred *override_cred)
 {
-	const struct cred *old = current->cred;
-
-	rcu_assign_pointer(current->cred, override_cred);
-	return old;
+	return rcu_replace_pointer(current->cred, override_cred, 1);
 }
 
 static inline const struct cred *revert_creds(const struct cred *revert_cred)
 {
-	const struct cred *override_cred = current->cred;
-
-	rcu_assign_pointer(current->cred, revert_cred);
-	return override_cred;
+	return rcu_replace_pointer(current->cred, revert_cred, 1);
 }
 
 /**
diff --git a/include/linux/fsnotify.h b/include/linux/fsnotify.h
index 6a33288bd6a1..83d3ac97f826 100644
--- a/include/linux/fsnotify.h
+++ b/include/linux/fsnotify.h
@@ -171,6 +171,21 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask,
 }
 
 /*
+ * fsnotify_mmap_perm - permission hook before mmap of file range
+ */
+static inline int fsnotify_mmap_perm(struct file *file, int prot,
+				     const loff_t off, size_t len)
+{
+	/*
+	 * mmap() generates only pre-content events.
+	 */
+	if (!file || likely(!FMODE_FSNOTIFY_HSM(file->f_mode)))
+		return 0;
+
+	return fsnotify_pre_content(&file->f_path, &off, len);
+}
+
+/*
  * fsnotify_truncate_perm - permission hook before file truncate
  */
 static inline int fsnotify_truncate_perm(const struct path *path, loff_t length)
@@ -223,6 +238,12 @@ static inline int fsnotify_file_area_perm(struct file *file, int perm_mask,
 	return 0;
 }
 
+static inline int fsnotify_mmap_perm(struct file *file, int prot,
+				     const loff_t off, size_t len)
+{
+	return 0;
+}
+
 static inline int fsnotify_truncate_perm(const struct path *path, loff_t length)
 {
 	return 0;
diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
index bf5f7256bd28..76a75ec03dd6 100644
--- a/include/linux/hugetlb.h
+++ b/include/linux/hugetlb.h
@@ -682,6 +682,7 @@ struct huge_bootmem_page {
 
 int isolate_or_dissolve_huge_page(struct page *page, struct list_head *list);
 int replace_free_hugepage_folios(unsigned long start_pfn, unsigned long end_pfn);
+void wait_for_freed_hugetlb_folios(void);
 struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma,
 				unsigned long addr, bool cow_from_owner);
 struct folio *alloc_hugetlb_folio_nodemask(struct hstate *h, int preferred_nid,
@@ -1068,6 +1069,10 @@ static inline int replace_free_hugepage_folios(unsigned long start_pfn,
 	return 0;
 }
 
+static inline void wait_for_freed_hugetlb_folios(void)
+{
+}
+
 static inline struct folio *alloc_hugetlb_folio(struct vm_area_struct *vma,
 					   unsigned long addr,
 					   bool cow_from_owner)
diff --git a/include/linux/log2.h b/include/linux/log2.h
index 9f30d087a128..1366cb688a6d 100644
--- a/include/linux/log2.h
+++ b/include/linux/log2.h
@@ -41,7 +41,7 @@ int __ilog2_u64(u64 n)
  * *not* considered a power of two.
  * Return: true if @n is a power of 2, otherwise false.
  */
-static inline __attribute__((const))
+static __always_inline __attribute__((const))
 bool is_power_of_2(unsigned long n)
 {
 	return (n != 0 && ((n & (n - 1)) == 0));
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7b1068ddcbb7..8483e09aeb2c 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -3420,7 +3420,6 @@ extern vm_fault_t filemap_fault(struct vm_fault *vmf);
 extern vm_fault_t filemap_map_pages(struct vm_fault *vmf,
 		pgoff_t start_pgoff, pgoff_t end_pgoff);
 extern vm_fault_t filemap_page_mkwrite(struct vm_fault *vmf);
-extern vm_fault_t filemap_fsnotify_fault(struct vm_fault *vmf);
 
 extern unsigned long stack_guard_gap;
 /* Generic expand stack which grows the stack according to GROWS{UP,DOWN} */
diff --git a/include/linux/of.h b/include/linux/of.h
index eaf0e2a2b75c..5e52d90f6408 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -314,6 +314,9 @@ extern struct property *of_find_property(const struct device_node *np,
 extern bool of_property_read_bool(const struct device_node *np, const char *propname);
 extern int of_property_count_elems_of_size(const struct device_node *np,
 				const char *propname, int elem_size);
+extern int of_property_read_u16_index(const struct device_node *np,
+				       const char *propname,
+				       u32 index, u16 *out_value);
 extern int of_property_read_u32_index(const struct device_node *np,
 				       const char *propname,
 				       u32 index, u32 *out_value);
@@ -627,6 +630,12 @@ static inline int of_property_count_elems_of_size(const struct device_node *np,
 	return -ENOSYS;
 }
 
+static inline int of_property_read_u16_index(const struct device_node *np,
+			const char *propname, u32 index, u16 *out_value)
+{
+	return -ENOSYS;
+}
+
 static inline int of_property_read_u32_index(const struct device_node *np,
 			const char *propname, u32 index, u32 *out_value)
 {
diff --git a/include/linux/pipe_fs_i.h b/include/linux/pipe_fs_i.h
index 8ff23bf5a819..b698758000f8 100644
--- a/include/linux/pipe_fs_i.h
+++ b/include/linux/pipe_fs_i.h
@@ -31,6 +31,33 @@ struct pipe_buffer {
 	unsigned long private;
 };
 
+/*
+ * Really only alpha needs 32-bit fields, but
+ * might as well do it for 64-bit architectures
+ * since that's what we've historically done,
+ * and it makes 'head_tail' always be a simple
+ * 'unsigned long'.
+ */
+#ifdef CONFIG_64BIT
+typedef unsigned int pipe_index_t;
+#else
+typedef unsigned short pipe_index_t;
+#endif
+
+/*
+ * We have to declare this outside 'struct pipe_inode_info',
+ * but then we can't use 'union pipe_index' for an anonymous
+ * union, so we end up having to duplicate this declaration
+ * below. Annoying.
+ */
+union pipe_index {
+	unsigned long head_tail;
+	struct {
+		pipe_index_t head;
+		pipe_index_t tail;
+	};
+};
+
 /**
  *	struct pipe_inode_info - a linux kernel pipe
  *	@mutex: mutex protecting the whole thing
@@ -38,6 +65,7 @@ struct pipe_buffer {
  *	@wr_wait: writer wait point in case of full pipe
  *	@head: The point of buffer production
  *	@tail: The point of buffer consumption
+ *	@head_tail: unsigned long union of @head and @tail
  *	@note_loss: The next read() should insert a data-lost message
  *	@max_usage: The maximum number of slots that may be used in the ring
  *	@ring_size: total number of buffers (should be a power of 2)
@@ -58,8 +86,16 @@ struct pipe_buffer {
 struct pipe_inode_info {
 	struct mutex mutex;
 	wait_queue_head_t rd_wait, wr_wait;
-	unsigned int head;
-	unsigned int tail;
+
+	/* This has to match the 'union pipe_index' above */
+	union {
+		unsigned long head_tail;
+		struct {
+			pipe_index_t head;
+			pipe_index_t tail;
+		};
+	};
+
 	unsigned int max_usage;
 	unsigned int ring_size;
 	unsigned int nr_accounted;
@@ -141,23 +177,23 @@ static inline bool pipe_has_watch_queue(const struct pipe_inode_info *pipe)
 }
 
 /**
- * pipe_empty - Return true if the pipe is empty
+ * pipe_occupancy - Return number of slots used in the pipe
  * @head: The pipe ring head pointer
  * @tail: The pipe ring tail pointer
  */
-static inline bool pipe_empty(unsigned int head, unsigned int tail)
+static inline unsigned int pipe_occupancy(unsigned int head, unsigned int tail)
 {
-	return head == tail;
+	return (pipe_index_t)(head - tail);
 }
 
 /**
- * pipe_occupancy - Return number of slots used in the pipe
+ * pipe_empty - Return true if the pipe is empty
  * @head: The pipe ring head pointer
  * @tail: The pipe ring tail pointer
  */
-static inline unsigned int pipe_occupancy(unsigned int head, unsigned int tail)
+static inline bool pipe_empty(unsigned int head, unsigned int tail)
 {
-	return head - tail;
+	return !pipe_occupancy(head, tail);
 }
 
 /**
@@ -173,6 +209,33 @@ static inline bool pipe_full(unsigned int head, unsigned int tail,
 }
 
 /**
+ * pipe_is_full - Return true if the pipe is full
+ * @pipe: the pipe
+ */
+static inline bool pipe_is_full(const struct pipe_inode_info *pipe)
+{
+	return pipe_full(pipe->head, pipe->tail, pipe->max_usage);
+}
+
+/**
+ * pipe_is_empty - Return true if the pipe is empty
+ * @pipe: the pipe
+ */
+static inline bool pipe_is_empty(const struct pipe_inode_info *pipe)
+{
+	return pipe_empty(pipe->head, pipe->tail);
+}
+
+/**
+ * pipe_buf_usage - Return how many pipe buffers are in use
+ * @pipe: the pipe
+ */
+static inline unsigned int pipe_buf_usage(const struct pipe_inode_info *pipe)
+{
+	return pipe_occupancy(pipe->head, pipe->tail);
+}
+
+/**
  * pipe_buf - Return the pipe buffer for the specified slot in the pipe ring
  * @pipe: The pipe to access
  * @slot: The slot of interest
@@ -245,15 +308,6 @@ static inline bool pipe_buf_try_steal(struct pipe_inode_info *pipe,
 	return buf->ops->try_steal(pipe, buf);
 }
 
-static inline void pipe_discard_from(struct pipe_inode_info *pipe,
-		unsigned int old_head)
-{
-	unsigned int mask = pipe->ring_size - 1;
-
-	while (pipe->head > old_head)
-		pipe_buf_release(pipe, &pipe->bufs[--pipe->head & mask]);
-}
-
 /* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
    memory allocation, whereas PIPE_BUF makes atomicity guarantees.  */
 #define PIPE_SIZE		PAGE_SIZE
diff --git a/include/linux/platform_profile.h b/include/linux/platform_profile.h
index 8ab5b0e8eb2c..8c9df7dadd5d 100644
--- a/include/linux/platform_profile.h
+++ b/include/linux/platform_profile.h
@@ -33,6 +33,8 @@ enum platform_profile_option {
  * @probe: Callback to setup choices available to the new class device. These
  *	   choices will only be enforced when setting a new profile, not when
  *	   getting the current one.
+ * @hidden_choices: Callback to setup choices that are not visible to the user
+ *		    but can be set by the driver.
  * @profile_get: Callback that will be called when showing the current platform
  *		 profile in sysfs.
  * @profile_set: Callback that will be called when storing a new platform
@@ -40,6 +42,7 @@ enum platform_profile_option {
  */
 struct platform_profile_ops {
 	int (*probe)(void *drvdata, unsigned long *choices);
+	int (*hidden_choices)(void *drvdata, unsigned long *choices);
 	int (*profile_get)(struct device *dev, enum platform_profile_option *profile);
 	int (*profile_set)(struct device *dev, enum platform_profile_option profile);
 };
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 9632e3318e0d..9c15365a30c0 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1701,7 +1701,7 @@ extern struct pid *cad_pid;
 #define PF_USED_MATH		0x00002000	/* If unset the fpu must be initialized before use */
 #define PF_USER_WORKER		0x00004000	/* Kernel thread cloned from userspace thread */
 #define PF_NOFREEZE		0x00008000	/* This thread should not be frozen */
-#define PF__HOLE__00010000	0x00010000
+#define PF_KCOMPACTD		0x00010000	/* I am kcompactd */
 #define PF_KSWAPD		0x00020000	/* I am kswapd */
 #define PF_MEMALLOC_NOFS	0x00040000	/* All allocations inherit GFP_NOFS. See memalloc_nfs_save() */
 #define PF_MEMALLOC_NOIO	0x00080000	/* All allocations inherit GFP_NOIO. See memalloc_noio_save() */