spi: Header and core clean up and refactoring

index ae2693ba1744..8e70f4183e62 100644
@@ -631,6 +631,16 @@ static int __spi_add_device(struct spi_device *spi)
 	struct device *dev = ctlr->dev.parent;
 	int status;
 
+	/* Chipselects are numbered 0..max; validate. */
+	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {
+		dev_err(dev, "cs%d >= max %d\n", spi_get_chipselect(spi, 0),
+			ctlr->num_chipselect);
+		return -EINVAL;
+	}
+
+	/* Set the bus ID string */
+	spi_dev_set_name(spi);
+
 	/*
 	 * We need to make sure there's no other device with this
 	 * chipselect **BEFORE** we call setup(), else we'll trash

@@ -689,19 +699,8 @@ static int __spi_add_device(struct spi_device *spi)
 int spi_add_device(struct spi_device *spi)
 {
 	struct spi_controller *ctlr = spi->controller;
-	struct device *dev = ctlr->dev.parent;
 	int status;
 
-	/* Chipselects are numbered 0..max; validate. */
-	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {
-		dev_err(dev, "cs%d >= max %d\n", spi_get_chipselect(spi, 0),
-			ctlr->num_chipselect);
-		return -EINVAL;
-	}
-
-	/* Set the bus ID string */
-	spi_dev_set_name(spi);
-
 	mutex_lock(&ctlr->add_lock);
 	status = __spi_add_device(spi);
 	mutex_unlock(&ctlr->add_lock);

@@ -712,17 +711,6 @@ EXPORT_SYMBOL_GPL(spi_add_device);
 static int spi_add_device_locked(struct spi_device *spi)
 {
 	struct spi_controller *ctlr = spi->controller;
-	struct device *dev = ctlr->dev.parent;
-
-	/* Chipselects are numbered 0..max; validate. */
-	if (spi_get_chipselect(spi, 0) >= ctlr->num_chipselect) {
-		dev_err(dev, "cs%d >= max %d\n", spi_get_chipselect(spi, 0),
-			ctlr->num_chipselect);
-		return -EINVAL;
-	}
-
-	/* Set the bus ID string */
-	spi_dev_set_name(spi);
 
 	WARN_ON(!mutex_is_locked(&ctlr->add_lock));
 	return __spi_add_device(spi);

index 8e70f4183e62..05f702339182 100644
@@ -708,14 +708,6 @@ int spi_add_device(struct spi_device *spi)
 }
 EXPORT_SYMBOL_GPL(spi_add_device);
 
-static int spi_add_device_locked(struct spi_device *spi)
-{
-	struct spi_controller *ctlr = spi->controller;
-
-	WARN_ON(!mutex_is_locked(&ctlr->add_lock));
-	return __spi_add_device(spi);
-}
-
 /**
  * spi_new_device - instantiate one new SPI device
  * @ctlr: Controller to which device is connected

@@ -2417,11 +2409,12 @@ static void of_register_spi_devices(struct spi_controller *ctlr) { }
 struct spi_device *spi_new_ancillary_device(struct spi_device *spi,
 					     u8 chip_select)
 {
+	struct spi_controller *ctlr = spi->controller;
 	struct spi_device *ancillary;
 	int rc = 0;
 
 	/* Alloc an spi_device */
-	ancillary = spi_alloc_device(spi->controller);
+	ancillary = spi_alloc_device(ctlr);
 	if (!ancillary) {
 		rc = -ENOMEM;
 		goto err_out;

@@ -2436,8 +2429,10 @@ struct spi_device *spi_new_ancillary_device(struct spi_device *spi,
 	ancillary->max_speed_hz = spi->max_speed_hz;
 	ancillary->mode = spi->mode;
 
+	WARN_ON(!mutex_is_locked(&ctlr->add_lock));
+
 	/* Register the new device */
-	rc = spi_add_device_locked(ancillary);
+	rc = __spi_add_device(ancillary);
 	if (rc) {
 		dev_err(&spi->dev, "failed to register ancillary device\n");
 		goto err_out;

index 05f702339182..8d6304cb061e 100644
@@ -3877,11 +3877,9 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 	 */
 	if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits & SPI_CS_WORD) ||
 					  spi_get_csgpiod(spi, 0))) {
-		size_t maxsize;
+		size_t maxsize = BITS_TO_BYTES(spi->bits_per_word);
 		int ret;
 
-		maxsize = (spi->bits_per_word + 7) / 8;
-
 		/* spi_split_transfers_maxsize() requires message->spi */
 		message->spi = spi;
 

index 04daf61dfd3f..7f8b478fdeb3 100644
@@ -13,6 +13,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/kthread.h>
 #include <linux/mod_devicetable.h>
+#include <linux/overflow.h>
 #include <linux/scatterlist.h>
 #include <linux/slab.h>
 #include <linux/u64_stats_sync.h>

@@ -1085,6 +1086,8 @@ struct spi_transfer {
  * @state: for use by whichever driver currently owns the message
  * @resources: for resource management when the SPI message is processed
  * @prepared: spi_prepare_message was called for the this message
+ * @t: for use with spi_message_alloc() when message and transfers have
+ *	been allocated together
  *
  * A @spi_message is used to execute an atomic sequence of data transfers,
  * each represented by a struct spi_transfer.  The sequence is "atomic"

@@ -1139,6 +1142,9 @@ struct spi_message {
 
 	/* List of spi_res resources when the SPI message is processed */
 	struct list_head        resources;
+
+	/* For embedding transfers into the memory of the message */
+	struct spi_transfer	t[];
 };
 
 static inline void spi_message_init_no_memset(struct spi_message *m)

@@ -1199,16 +1205,13 @@ static inline struct spi_message *spi_message_alloc(unsigned ntrans, gfp_t flags
 {
 	struct spi_message *m;
 
-	m = kzalloc(sizeof(struct spi_message)
-			+ ntrans * sizeof(struct spi_transfer),
-			flags);
+	m = kzalloc(struct_size(m, t, ntrans), flags);
 	if (m) {
 		unsigned i;
-		struct spi_transfer *t = (struct spi_transfer *)(m + 1);
 
 		spi_message_init_no_memset(m);
-		for (i = 0; i < ntrans; i++, t++)
-			spi_message_add_tail(t, m);
+		for (i = 0; i < ntrans; i++)
+			spi_message_add_tail(&m->t[i], m);
 	}
 	return m;
 }