From ea08eeccae9297f7aabd2ef7f0c2517ac4549acc Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:18:26 +0000
Subject: [PATCH] write in 30M

---
 kernel/drivers/spi/spi.c |  934 +++++++++++++++++++++++++++++++++++++++++++++------------
 1 files changed, 734 insertions(+), 200 deletions(-)

diff --git a/kernel/drivers/spi/spi.c b/kernel/drivers/spi/spi.c
index fefb700..b1a638d 100644
--- a/kernel/drivers/spi/spi.c
+++ b/kernel/drivers/spi/spi.c
@@ -1,10 +1,8 @@
 // SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * SPI init/core code
- *
- * Copyright (C) 2005 David Brownell
- * Copyright (C) 2008 Secret Lab Technologies Ltd.
- */
+// SPI init/core code
+//
+// Copyright (C) 2005 David Brownell
+// Copyright (C) 2008 Secret Lab Technologies Ltd.
 
 #include <linux/kernel.h>
 #include <linux/device.h>
@@ -21,6 +19,7 @@
 #include <linux/spi/spi.h>
 #include <linux/spi/spi-mem.h>
 #include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/pm_runtime.h>
 #include <linux/pm_domain.h>
 #include <linux/property.h>
@@ -37,6 +36,8 @@
 
 #define CREATE_TRACE_POINTS
 #include <trace/events/spi.h>
+EXPORT_TRACEPOINT_SYMBOL(spi_transfer_start);
+EXPORT_TRACEPOINT_SYMBOL(spi_transfer_stop);
 
 #include "internals.h"
 
@@ -45,10 +46,6 @@
 static void spidev_release(struct device *dev)
 {
 	struct spi_device	*spi = to_spi_device(dev);
-
-	/* spi controllers may cleanup for released devices */
-	if (spi->controller->cleanup)
-		spi->controller->cleanup(spi);
 
 	spi_controller_put(spi->controller);
 	kfree(spi->driver_override);
@@ -91,7 +88,7 @@
 	if (len) {
 		spi->driver_override = driver_override;
 	} else {
-		/* Emptry string, disable driver override */
+		/* Empty string, disable driver override */
 		spi->driver_override = NULL;
 		kfree(driver_override);
 	}
@@ -469,7 +466,7 @@
 static LIST_HEAD(spi_controller_list);
 
 /*
- * Used to protect add/del opertion for board_info list and
+ * Used to protect add/del operation for board_info list and
  * spi_controller list, and their matching process
  * also used to protect object of type struct idr
  */
@@ -516,6 +513,7 @@
 	spi->dev.bus = &spi_bus_type;
 	spi->dev.release = spidev_release;
 	spi->cs_gpio = -ENOENT;
+	spi->mode = ctlr->buswidth_override_bits;
 
 	spin_lock_init(&spi->statistics.lock);
 
@@ -546,6 +544,12 @@
 	    spi->chip_select == new_spi->chip_select)
 		return -EBUSY;
 	return 0;
+}
+
+static void spi_cleanup(struct spi_device *spi)
+{
+	if (spi->controller->cleanup)
+		spi->controller->cleanup(spi);
 }
 
 /**
@@ -593,7 +597,10 @@
 		goto done;
 	}
 
-	if (ctlr->cs_gpios)
+	/* Descriptors take precedence */
+	if (ctlr->cs_gpiods)
+		spi->cs_gpiod = ctlr->cs_gpiods[spi->chip_select];
+	else if (ctlr->cs_gpios)
 		spi->cs_gpio = ctlr->cs_gpios[spi->chip_select];
 
 	/* Drivers may modify this initial i/o setup, but will
@@ -609,11 +616,13 @@
 
 	/* Device may be bound to an active driver when this returns */
 	status = device_add(&spi->dev);
-	if (status < 0)
+	if (status < 0) {
 		dev_err(dev, "can't add %s, status %d\n",
 				dev_name(&spi->dev), status);
-	else
+		spi_cleanup(spi);
+	} else {
 		dev_dbg(dev, "registered child %s\n", dev_name(&spi->dev));
+	}
 
 done:
 	mutex_unlock(&spi_add_lock);
@@ -706,7 +715,9 @@
 	}
 	if (ACPI_COMPANION(&spi->dev))
 		acpi_device_clear_enumerated(ACPI_COMPANION(&spi->dev));
-	device_unregister(&spi->dev);
+	device_del(&spi->dev);
+	spi_cleanup(spi);
+	put_device(&spi->dev);
 }
 EXPORT_SYMBOL_GPL(spi_unregister_device);
 
@@ -782,21 +793,68 @@
 
 /*-------------------------------------------------------------------------*/
 
-static void spi_set_cs(struct spi_device *spi, bool enable)
+static void spi_set_cs(struct spi_device *spi, bool enable, bool force)
 {
+	bool enable1 = enable;
+
+	/*
+	 * Avoid calling into the driver (or doing delays) if the chip select
+	 * isn't actually changing from the last time this was called.
+	 */
+	if (!force && (spi->controller->last_cs_enable == enable) &&
+	    (spi->controller->last_cs_mode_high == (spi->mode & SPI_CS_HIGH)))
+		return;
+
+	spi->controller->last_cs_enable = enable;
+	spi->controller->last_cs_mode_high = spi->mode & SPI_CS_HIGH;
+
+	if (!spi->controller->set_cs_timing) {
+		if (enable1)
+			spi_delay_exec(&spi->controller->cs_setup, NULL);
+		else
+			spi_delay_exec(&spi->controller->cs_hold, NULL);
+	}
+
 	if (spi->mode & SPI_CS_HIGH)
 		enable = !enable;
 
-	if (gpio_is_valid(spi->cs_gpio)) {
-		/* Honour the SPI_NO_CS flag */
-		if (!(spi->mode & SPI_NO_CS))
-			gpio_set_value(spi->cs_gpio, !enable);
+	if (spi->cs_gpiod || gpio_is_valid(spi->cs_gpio)) {
+		if (!(spi->mode & SPI_NO_CS)) {
+			if (spi->cs_gpiod) {
+				/*
+				 * Historically ACPI has no means of the GPIO polarity and
+				 * thus the SPISerialBus() resource defines it on the per-chip
+				 * basis. In order to avoid a chain of negations, the GPIO
+				 * polarity is considered being Active High. Even for the cases
+				 * when _DSD() is involved (in the updated versions of ACPI)
+				 * the GPIO CS polarity must be defined Active High to avoid
+				 * ambiguity. That's why we use enable, that takes SPI_CS_HIGH
+				 * into account.
+				 */
+				if (has_acpi_companion(&spi->dev))
+					gpiod_set_value_cansleep(spi->cs_gpiod, !enable);
+				else
+					/* Polarity handled by GPIO library */
+					gpiod_set_value_cansleep(spi->cs_gpiod, enable1);
+			} else {
+				/*
+				 * invert the enable line, as active low is
+				 * default for SPI.
+				 */
+				gpio_set_value_cansleep(spi->cs_gpio, !enable);
+			}
+		}
 		/* Some SPI masters need both GPIO CS & slave_select */
 		if ((spi->controller->flags & SPI_MASTER_GPIO_SS) &&
 		    spi->controller->set_cs)
 			spi->controller->set_cs(spi, !enable);
 	} else if (spi->controller->set_cs) {
 		spi->controller->set_cs(spi, !enable);
+	}
+
+	if (!spi->controller->set_cs_timing) {
+		if (!enable1)
+			spi_delay_exec(&spi->controller->cs_inactive, NULL);
 	}
 }
 
@@ -823,10 +881,10 @@
 	int i, ret;
 
 	if (vmalloced_buf || kmap_buf) {
-		desc_len = min_t(int, max_seg_size, PAGE_SIZE);
+		desc_len = min_t(unsigned long, max_seg_size, PAGE_SIZE);
 		sgs = DIV_ROUND_UP(len + offset_in_page(buf), desc_len);
 	} else if (virt_addr_valid(buf)) {
-		desc_len = min_t(int, max_seg_size, ctlr->max_dma_len);
+		desc_len = min_t(size_t, max_seg_size, ctlr->max_dma_len);
 		sgs = DIV_ROUND_UP(len, desc_len);
 	} else {
 		return -EINVAL;
@@ -888,6 +946,8 @@
 	if (sgt->orig_nents) {
 		dma_unmap_sg(dev, sgt->sgl, sgt->orig_nents, dir);
 		sg_free_table(sgt);
+		sgt->orig_nents = 0;
+		sgt->nents = 0;
 	}
 }
 
@@ -965,6 +1025,8 @@
 		spi_unmap_buf(ctlr, tx_dev, &xfer->tx_sg, DMA_TO_DEVICE);
 	}
 
+	ctlr->cur_msg_mapped = false;
+
 	return 0;
 }
 #else /* !CONFIG_HAS_DMA */
@@ -1006,7 +1068,8 @@
 	void *tmp;
 	unsigned int max_tx, max_rx;
 
-	if (ctlr->flags & (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX)) {
+	if ((ctlr->flags & (SPI_CONTROLLER_MUST_RX | SPI_CONTROLLER_MUST_TX))
+		&& !(msg->spi->mode & SPI_3WIRE)) {
 		max_tx = 0;
 		max_rx = 0;
 
@@ -1058,7 +1121,8 @@
 {
 	struct spi_statistics *statm = &ctlr->statistics;
 	struct spi_statistics *stats = &msg->spi->statistics;
-	unsigned long long ms = 1;
+	u32 speed_hz = xfer->speed_hz;
+	unsigned long long ms;
 
 	if (spi_controller_is_slave(ctlr)) {
 		if (wait_for_completion_interruptible(&ctlr->xfer_completion)) {
@@ -1066,8 +1130,11 @@
 			return -EINTR;
 		}
 	} else {
+		if (!speed_hz)
+			speed_hz = 100000;
+
 		ms = 8LL * 1000LL * xfer->len;
-		do_div(ms, xfer->speed_hz);
+		do_div(ms, speed_hz);
 		ms += ms + 200; /* some tolerance */
 
 		if (ms > UINT_MAX)
@@ -1088,6 +1155,99 @@
 	return 0;
 }
 
+static void _spi_transfer_delay_ns(u32 ns)
+{
+	if (!ns)
+		return;
+	if (ns <= 1000) {
+		ndelay(ns);
+	} else {
+		u32 us = DIV_ROUND_UP(ns, 1000);
+
+		if (us <= 10)
+			udelay(us);
+		else
+			usleep_range(us, us + DIV_ROUND_UP(us, 10));
+	}
+}
+
+int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer)
+{
+	u32 delay = _delay->value;
+	u32 unit = _delay->unit;
+	u32 hz;
+
+	if (!delay)
+		return 0;
+
+	switch (unit) {
+	case SPI_DELAY_UNIT_USECS:
+		delay *= 1000;
+		break;
+	case SPI_DELAY_UNIT_NSECS: /* nothing to do here */
+		break;
+	case SPI_DELAY_UNIT_SCK:
+		/* clock cycles need to be obtained from spi_transfer */
+		if (!xfer)
+			return -EINVAL;
+		/* if there is no effective speed know, then approximate
+		 * by underestimating with half the requested hz
+		 */
+		hz = xfer->effective_speed_hz ?: xfer->speed_hz / 2;
+		if (!hz)
+			return -EINVAL;
+		delay *= DIV_ROUND_UP(1000000000, hz);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return delay;
+}
+EXPORT_SYMBOL_GPL(spi_delay_to_ns);
+
+int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer)
+{
+	int delay;
+
+	might_sleep();
+
+	if (!_delay)
+		return -EINVAL;
+
+	delay = spi_delay_to_ns(_delay, xfer);
+	if (delay < 0)
+		return delay;
+
+	_spi_transfer_delay_ns(delay);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(spi_delay_exec);
+
+static void _spi_transfer_cs_change_delay(struct spi_message *msg,
+					  struct spi_transfer *xfer)
+{
+	u32 delay = xfer->cs_change_delay.value;
+	u32 unit = xfer->cs_change_delay.unit;
+	int ret;
+
+	/* return early on "fast" mode - for everything but USECS */
+	if (!delay) {
+		if (unit == SPI_DELAY_UNIT_USECS)
+			_spi_transfer_delay_ns(10000);
+		return;
+	}
+
+	ret = spi_delay_exec(&xfer->cs_change_delay, xfer);
+	if (ret) {
+		dev_err_once(&msg->spi->dev,
+			     "Use of unsupported delay unit %i, using default of 10us\n",
+			     unit);
+		_spi_transfer_delay_ns(10000);
+	}
+}
+
 /*
  * spi_transfer_one_message - Default implementation of transfer_one_message()
  *
@@ -1104,7 +1264,7 @@
 	struct spi_statistics *statm = &ctlr->statistics;
 	struct spi_statistics *stats = &msg->spi->statistics;
 
-	spi_set_cs(msg->spi, true);
+	spi_set_cs(msg->spi, true, false);
 
 	SPI_STATISTICS_INCREMENT_FIELD(statm, messages);
 	SPI_STATISTICS_INCREMENT_FIELD(stats, messages);
@@ -1115,11 +1275,25 @@
 		spi_statistics_add_transfer_stats(statm, xfer, ctlr);
 		spi_statistics_add_transfer_stats(stats, xfer, ctlr);
 
-		if (xfer->tx_buf || xfer->rx_buf) {
+		if (!ctlr->ptp_sts_supported) {
+			xfer->ptp_sts_word_pre = 0;
+			ptp_read_system_prets(xfer->ptp_sts);
+		}
+
+		if ((xfer->tx_buf || xfer->rx_buf) && xfer->len) {
 			reinit_completion(&ctlr->xfer_completion);
 
+fallback_pio:
 			ret = ctlr->transfer_one(ctlr, msg->spi, xfer);
 			if (ret < 0) {
+				if (ctlr->cur_msg_mapped &&
+				   (xfer->error & SPI_TRANS_FAIL_NO_START)) {
+					__spi_unmap_msg(ctlr, msg);
+					ctlr->fallback = true;
+					xfer->error &= ~SPI_TRANS_FAIL_NO_START;
+					goto fallback_pio;
+				}
+
 				SPI_STATISTICS_INCREMENT_FIELD(statm,
 							       errors);
 				SPI_STATISTICS_INCREMENT_FIELD(stats,
@@ -1141,28 +1315,26 @@
 					xfer->len);
 		}
 
+		if (!ctlr->ptp_sts_supported) {
+			ptp_read_system_postts(xfer->ptp_sts);
+			xfer->ptp_sts_word_post = xfer->len;
+		}
+
 		trace_spi_transfer_stop(msg, xfer);
 
 		if (msg->status != -EINPROGRESS)
 			goto out;
 
-		if (xfer->delay_usecs) {
-			u16 us = xfer->delay_usecs;
-
-			if (us <= 10)
-				udelay(us);
-			else
-				usleep_range(us, us + DIV_ROUND_UP(us, 10));
-		}
+		spi_transfer_delay_exec(xfer);
 
 		if (xfer->cs_change) {
 			if (list_is_last(&xfer->transfer_list,
 					 &msg->transfers)) {
 				keep_cs = true;
 			} else {
-				spi_set_cs(msg->spi, false);
-				udelay(10);
-				spi_set_cs(msg->spi, true);
+				spi_set_cs(msg->spi, false, false);
+				_spi_transfer_cs_change_delay(msg, xfer);
+				spi_set_cs(msg->spi, true, false);
 			}
 		}
 
@@ -1171,7 +1343,7 @@
 
 out:
 	if (ret != 0 || !keep_cs)
-		spi_set_cs(msg->spi, false);
+		spi_set_cs(msg->spi, false, false);
 
 	if (msg->status == -EINPROGRESS)
 		msg->status = ret;
@@ -1198,6 +1370,14 @@
 }
 EXPORT_SYMBOL_GPL(spi_finalize_current_transfer);
 
+static void spi_idle_runtime_pm(struct spi_controller *ctlr)
+{
+	if (ctlr->auto_runtime_pm) {
+		pm_runtime_mark_last_busy(ctlr->dev.parent);
+		pm_runtime_put_autosuspend(ctlr->dev.parent);
+	}
+}
+
 /**
  * __spi_pump_messages - function which processes spi message queue
  * @ctlr: controller to process queue for
@@ -1213,8 +1393,10 @@
  */
 static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread)
 {
-	unsigned long flags;
+	struct spi_transfer *xfer;
+	struct spi_message *msg;
 	bool was_busy = false;
+	unsigned long flags;
 	int ret;
 
 	/* Lock queue */
@@ -1228,7 +1410,7 @@
 
 	/* If another context is idling the device then defer */
 	if (ctlr->idling) {
-		kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages);
+		kthread_queue_work(ctlr->kworker, &ctlr->pump_messages);
 		spin_unlock_irqrestore(&ctlr->queue_lock, flags);
 		return;
 	}
@@ -1240,10 +1422,17 @@
 			return;
 		}
 
-		/* Only do teardown in the thread */
+		/* Defer any non-atomic teardown to the thread */
 		if (!in_kthread) {
-			kthread_queue_work(&ctlr->kworker,
-					   &ctlr->pump_messages);
+			if (!ctlr->dummy_rx && !ctlr->dummy_tx &&
+			    !ctlr->unprepare_transfer_hardware) {
+				spi_idle_runtime_pm(ctlr);
+				ctlr->busy = false;
+				trace_spi_controller_idle(ctlr);
+			} else {
+				kthread_queue_work(ctlr->kworker,
+						   &ctlr->pump_messages);
+			}
 			spin_unlock_irqrestore(&ctlr->queue_lock, flags);
 			return;
 		}
@@ -1260,10 +1449,7 @@
 		    ctlr->unprepare_transfer_hardware(ctlr))
 			dev_err(&ctlr->dev,
 				"failed to unprepare transfer hardware\n");
-		if (ctlr->auto_runtime_pm) {
-			pm_runtime_mark_last_busy(ctlr->dev.parent);
-			pm_runtime_put_autosuspend(ctlr->dev.parent);
-		}
+		spi_idle_runtime_pm(ctlr);
 		trace_spi_controller_idle(ctlr);
 
 		spin_lock_irqsave(&ctlr->queue_lock, flags);
@@ -1273,10 +1459,10 @@
 	}
 
 	/* Extract head of queue */
-	ctlr->cur_msg =
-		list_first_entry(&ctlr->queue, struct spi_message, queue);
+	msg = list_first_entry(&ctlr->queue, struct spi_message, queue);
+	ctlr->cur_msg = msg;
 
-	list_del_init(&ctlr->cur_msg->queue);
+	list_del_init(&msg->queue);
 	if (ctlr->busy)
 		was_busy = true;
 	else
@@ -1303,37 +1489,49 @@
 		ret = ctlr->prepare_transfer_hardware(ctlr);
 		if (ret) {
 			dev_err(&ctlr->dev,
-				"failed to prepare transfer hardware\n");
+				"failed to prepare transfer hardware: %d\n",
+				ret);
 
 			if (ctlr->auto_runtime_pm)
 				pm_runtime_put(ctlr->dev.parent);
+
+			msg->status = ret;
+			spi_finalize_current_message(ctlr);
+
 			mutex_unlock(&ctlr->io_mutex);
 			return;
 		}
 	}
 
-	trace_spi_message_start(ctlr->cur_msg);
+	trace_spi_message_start(msg);
 
 	if (ctlr->prepare_message) {
-		ret = ctlr->prepare_message(ctlr, ctlr->cur_msg);
+		ret = ctlr->prepare_message(ctlr, msg);
 		if (ret) {
 			dev_err(&ctlr->dev, "failed to prepare message: %d\n",
 				ret);
-			ctlr->cur_msg->status = ret;
+			msg->status = ret;
 			spi_finalize_current_message(ctlr);
 			goto out;
 		}
 		ctlr->cur_msg_prepared = true;
 	}
 
-	ret = spi_map_msg(ctlr, ctlr->cur_msg);
+	ret = spi_map_msg(ctlr, msg);
 	if (ret) {
-		ctlr->cur_msg->status = ret;
+		msg->status = ret;
 		spi_finalize_current_message(ctlr);
 		goto out;
 	}
 
-	ret = ctlr->transfer_one_message(ctlr, ctlr->cur_msg);
+	if (!ctlr->ptp_sts_supported && !ctlr->transfer_one) {
+		list_for_each_entry(xfer, &msg->transfers, transfer_list) {
+			xfer->ptp_sts_word_pre = 0;
+			ptp_read_system_prets(xfer->ptp_sts);
+		}
+	}
+
+	ret = ctlr->transfer_one_message(ctlr, msg);
 	if (ret) {
 		dev_err(&ctlr->dev,
 			"failed to transfer one message from queue\n");
@@ -1360,20 +1558,124 @@
 	__spi_pump_messages(ctlr, true);
 }
 
+/**
+ * spi_take_timestamp_pre - helper for drivers to collect the beginning of the
+ *			    TX timestamp for the requested byte from the SPI
+ *			    transfer. The frequency with which this function
+ *			    must be called (once per word, once for the whole
+ *			    transfer, once per batch of words etc) is arbitrary
+ *			    as long as the @tx buffer offset is greater than or
+ *			    equal to the requested byte at the time of the
+ *			    call. The timestamp is only taken once, at the
+ *			    first such call. It is assumed that the driver
+ *			    advances its @tx buffer pointer monotonically.
+ * @ctlr: Pointer to the spi_controller structure of the driver
+ * @xfer: Pointer to the transfer being timestamped
+ * @progress: How many words (not bytes) have been transferred so far
+ * @irqs_off: If true, will disable IRQs and preemption for the duration of the
+ *	      transfer, for less jitter in time measurement. Only compatible
+ *	      with PIO drivers. If true, must follow up with
+ *	      spi_take_timestamp_post or otherwise system will crash.
+ *	      WARNING: for fully predictable results, the CPU frequency must
+ *	      also be under control (governor).
+ */
+void spi_take_timestamp_pre(struct spi_controller *ctlr,
+			    struct spi_transfer *xfer,
+			    size_t progress, bool irqs_off)
+{
+	if (!xfer->ptp_sts)
+		return;
+
+	if (xfer->timestamped)
+		return;
+
+	if (progress > xfer->ptp_sts_word_pre)
+		return;
+
+	/* Capture the resolution of the timestamp */
+	xfer->ptp_sts_word_pre = progress;
+
+	if (irqs_off) {
+		local_irq_save(ctlr->irq_flags);
+		preempt_disable();
+	}
+
+	ptp_read_system_prets(xfer->ptp_sts);
+}
+EXPORT_SYMBOL_GPL(spi_take_timestamp_pre);
+
+/**
+ * spi_take_timestamp_post - helper for drivers to collect the end of the
+ *			     TX timestamp for the requested byte from the SPI
+ *			     transfer. Can be called with an arbitrary
+ *			     frequency: only the first call where @tx exceeds
+ *			     or is equal to the requested word will be
+ *			     timestamped.
+ * @ctlr: Pointer to the spi_controller structure of the driver
+ * @xfer: Pointer to the transfer being timestamped
+ * @progress: How many words (not bytes) have been transferred so far
+ * @irqs_off: If true, will re-enable IRQs and preemption for the local CPU.
+ */
+void spi_take_timestamp_post(struct spi_controller *ctlr,
+			     struct spi_transfer *xfer,
+			     size_t progress, bool irqs_off)
+{
+	if (!xfer->ptp_sts)
+		return;
+
+	if (xfer->timestamped)
+		return;
+
+	if (progress < xfer->ptp_sts_word_post)
+		return;
+
+	ptp_read_system_postts(xfer->ptp_sts);
+
+	if (irqs_off) {
+		local_irq_restore(ctlr->irq_flags);
+		preempt_enable();
+	}
+
+	/* Capture the resolution of the timestamp */
+	xfer->ptp_sts_word_post = progress;
+
+	xfer->timestamped = true;
+}
+EXPORT_SYMBOL_GPL(spi_take_timestamp_post);
+
+/**
+ * spi_set_thread_rt - set the controller to pump at realtime priority
+ * @ctlr: controller to boost priority of
+ *
+ * This can be called because the controller requested realtime priority
+ * (by setting the ->rt value before calling spi_register_controller()) or
+ * because a device on the bus said that its transfers needed realtime
+ * priority.
+ *
+ * NOTE: at the moment if any device on a bus says it needs realtime then
+ * the thread will be at realtime priority for all transfers on that
+ * controller.  If this eventually becomes a problem we may see if we can
+ * find a way to boost the priority only temporarily during relevant
+ * transfers.
+ */
+static void spi_set_thread_rt(struct spi_controller *ctlr)
+{
+	dev_info(&ctlr->dev,
+		"will run message pump with realtime priority\n");
+	sched_set_fifo(ctlr->kworker->task);
+}
+
 static int spi_init_queue(struct spi_controller *ctlr)
 {
-	struct sched_param param = { .sched_priority = MAX_RT_PRIO - 1 };
-
 	ctlr->running = false;
 	ctlr->busy = false;
 
-	kthread_init_worker(&ctlr->kworker);
-	ctlr->kworker_task = kthread_run(kthread_worker_fn, &ctlr->kworker,
-					 "%s", dev_name(&ctlr->dev));
-	if (IS_ERR(ctlr->kworker_task)) {
-		dev_err(&ctlr->dev, "failed to create message pump task\n");
-		return PTR_ERR(ctlr->kworker_task);
+	ctlr->kworker = kthread_create_worker(0, dev_name(&ctlr->dev));
+	if (IS_ERR(ctlr->kworker)) {
+		dev_err(&ctlr->dev, "failed to create message pump kworker\n");
+		return PTR_ERR(ctlr->kworker);
 	}
+
 	kthread_init_work(&ctlr->pump_messages, spi_pump_messages);
 
 	/*
@@ -1383,11 +1685,8 @@
 	 * request and the scheduling of the message pump thread. Without this
 	 * setting the message pump thread will remain at default priority.
 	 */
-	if (ctlr->rt) {
-		dev_info(&ctlr->dev,
-			"will run message pump with realtime priority\n");
-		sched_setscheduler(ctlr->kworker_task, SCHED_FIFO, &param);
-	}
+	if (ctlr->rt)
+		spi_set_thread_rt(ctlr);
 
 	return 0;
 }
@@ -1426,6 +1725,7 @@
  */
 void spi_finalize_current_message(struct spi_controller *ctlr)
 {
+	struct spi_transfer *xfer;
 	struct spi_message *mesg;
 	unsigned long flags;
 	int ret;
@@ -1433,6 +1733,17 @@
 	spin_lock_irqsave(&ctlr->queue_lock, flags);
 	mesg = ctlr->cur_msg;
 	spin_unlock_irqrestore(&ctlr->queue_lock, flags);
+
+	if (!ctlr->ptp_sts_supported && !ctlr->transfer_one) {
+		list_for_each_entry(xfer, &mesg->transfers, transfer_list) {
+			ptp_read_system_postts(xfer->ptp_sts);
+			xfer->ptp_sts_word_post = xfer->len;
+		}
+	}
+
+	if (unlikely(ctlr->ptp_sts_supported))
+		list_for_each_entry(xfer, &mesg->transfers, transfer_list)
+			WARN_ON_ONCE(xfer->ptp_sts && !xfer->timestamped);
 
 	spi_unmap_msg(ctlr, mesg);
 
@@ -1454,7 +1765,8 @@
 	spin_lock_irqsave(&ctlr->queue_lock, flags);
 	ctlr->cur_msg = NULL;
 	ctlr->cur_msg_prepared = false;
-	kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages);
+	ctlr->fallback = false;
+	kthread_queue_work(ctlr->kworker, &ctlr->pump_messages);
 	spin_unlock_irqrestore(&ctlr->queue_lock, flags);
 
 	trace_spi_message_done(mesg);
@@ -1480,7 +1792,7 @@
 	ctlr->cur_msg = NULL;
 	spin_unlock_irqrestore(&ctlr->queue_lock, flags);
 
-	kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages);
+	kthread_queue_work(ctlr->kworker, &ctlr->pump_messages);
 
 	return 0;
 }
@@ -1536,8 +1848,7 @@
 		return ret;
 	}
 
-	kthread_flush_worker(&ctlr->kworker);
-	kthread_stop(ctlr->kworker_task);
+	kthread_destroy_worker(ctlr->kworker);
 
 	return 0;
 }
@@ -1560,7 +1871,7 @@
 
 	list_add_tail(&msg->queue, &ctlr->queue);
 	if (!ctlr->busy && need_pump)
-		kthread_queue_work(&ctlr->kworker, &ctlr->pump_messages);
+		kthread_queue_work(ctlr->kworker, &ctlr->pump_messages);
 
 	spin_unlock_irqrestore(&ctlr->queue_lock, flags);
 	return 0;
@@ -1637,12 +1948,12 @@
 		spi->mode |= SPI_CPHA;
 	if (of_property_read_bool(nc, "spi-cpol"))
 		spi->mode |= SPI_CPOL;
-	if (of_property_read_bool(nc, "spi-cs-high"))
-		spi->mode |= SPI_CS_HIGH;
 	if (of_property_read_bool(nc, "spi-3wire"))
 		spi->mode |= SPI_3WIRE;
 	if (of_property_read_bool(nc, "spi-lsb-first"))
 		spi->mode |= SPI_LSB_FIRST;
+	if (of_property_read_bool(nc, "spi-cs-high"))
+		spi->mode |= SPI_CS_HIGH;
 
 	/* Device DUAL/QUAD mode */
 	if (!of_property_read_u32(nc, "spi-tx-bus-width", &value)) {
@@ -1654,6 +1965,9 @@
 			break;
 		case 4:
 			spi->mode |= SPI_TX_QUAD;
+			break;
+		case 8:
+			spi->mode |= SPI_TX_OCTAL;
 			break;
 		default:
 			dev_warn(&ctlr->dev,
@@ -1673,6 +1987,9 @@
 		case 4:
 			spi->mode |= SPI_RX_QUAD;
 			break;
+		case 8:
+			spi->mode |= SPI_RX_OCTAL;
+			break;
 		default:
 			dev_warn(&ctlr->dev,
 				"spi-rx-bus-width %d not supported\n",
@@ -1682,7 +1999,7 @@
 	}
 
 	if (spi_controller_is_slave(ctlr)) {
-		if (strcmp(nc->name, "slave")) {
+		if (!of_node_name_eq(nc, "slave")) {
 			dev_err(&ctlr->dev, "%pOF is not called 'slave'\n",
 				nc);
 			return -EINVAL;
@@ -1700,13 +2017,8 @@
 	spi->chip_select = value;
 
 	/* Device speed */
-	rc = of_property_read_u32(nc, "spi-max-frequency", &value);
-	if (rc) {
-		dev_err(&ctlr->dev,
-			"%pOF has no valid 'spi-max-frequency' property (%d)\n", nc, rc);
-		return rc;
-	}
-	spi->max_speed_hz = value;
+	if (!of_property_read_u32(nc, "spi-max-frequency", &value))
+		spi->max_speed_hz = value;
 
 	return 0;
 }
@@ -1789,9 +2101,18 @@
 #endif
 
 #ifdef CONFIG_ACPI
-static void acpi_spi_parse_apple_properties(struct spi_device *spi)
+struct acpi_spi_lookup {
+	struct spi_controller 	*ctlr;
+	u32			max_speed_hz;
+	u32			mode;
+	int			irq;
+	u8			bits_per_word;
+	u8			chip_select;
+};
+
+static void acpi_spi_parse_apple_properties(struct acpi_device *dev,
+					    struct acpi_spi_lookup *lookup)
 {
-	struct acpi_device *dev = ACPI_COMPANION(&spi->dev);
 	const union acpi_object *obj;
 
 	if (!x86_apple_machine)
@@ -1799,35 +2120,46 @@
 
 	if (!acpi_dev_get_property(dev, "spiSclkPeriod", ACPI_TYPE_BUFFER, &obj)
 	    && obj->buffer.length >= 4)
-		spi->max_speed_hz  = NSEC_PER_SEC / *(u32 *)obj->buffer.pointer;
+		lookup->max_speed_hz  = NSEC_PER_SEC / *(u32 *)obj->buffer.pointer;
 
 	if (!acpi_dev_get_property(dev, "spiWordSize", ACPI_TYPE_BUFFER, &obj)
 	    && obj->buffer.length == 8)
-		spi->bits_per_word = *(u64 *)obj->buffer.pointer;
+		lookup->bits_per_word = *(u64 *)obj->buffer.pointer;
 
 	if (!acpi_dev_get_property(dev, "spiBitOrder", ACPI_TYPE_BUFFER, &obj)
 	    && obj->buffer.length == 8 && !*(u64 *)obj->buffer.pointer)
-		spi->mode |= SPI_LSB_FIRST;
+		lookup->mode |= SPI_LSB_FIRST;
 
 	if (!acpi_dev_get_property(dev, "spiSPO", ACPI_TYPE_BUFFER, &obj)
 	    && obj->buffer.length == 8 &&  *(u64 *)obj->buffer.pointer)
-		spi->mode |= SPI_CPOL;
+		lookup->mode |= SPI_CPOL;
 
 	if (!acpi_dev_get_property(dev, "spiSPH", ACPI_TYPE_BUFFER, &obj)
 	    && obj->buffer.length == 8 &&  *(u64 *)obj->buffer.pointer)
-		spi->mode |= SPI_CPHA;
+		lookup->mode |= SPI_CPHA;
 }
 
 static int acpi_spi_add_resource(struct acpi_resource *ares, void *data)
 {
-	struct spi_device *spi = data;
-	struct spi_controller *ctlr = spi->controller;
+	struct acpi_spi_lookup *lookup = data;
+	struct spi_controller *ctlr = lookup->ctlr;
 
 	if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
 		struct acpi_resource_spi_serialbus *sb;
+		acpi_handle parent_handle;
+		acpi_status status;
 
 		sb = &ares->data.spi_serial_bus;
 		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) {
+
+			status = acpi_get_handle(NULL,
+						 sb->resource_source.string_ptr,
+						 &parent_handle);
+
+			if (ACPI_FAILURE(status) ||
+			    ACPI_HANDLE(ctlr->dev.parent) != parent_handle)
+				return -ENODEV;
+
 			/*
 			 * ACPI DeviceSelection numbering is handled by the
 			 * host controller driver in Windows and can vary
@@ -1840,25 +2172,26 @@
 						sb->device_selection);
 				if (cs < 0)
 					return cs;
-				spi->chip_select = cs;
+				lookup->chip_select = cs;
 			} else {
-				spi->chip_select = sb->device_selection;
+				lookup->chip_select = sb->device_selection;
 			}
 
-			spi->max_speed_hz = sb->connection_speed;
+			lookup->max_speed_hz = sb->connection_speed;
+			lookup->bits_per_word = sb->data_bit_length;
 
 			if (sb->clock_phase == ACPI_SPI_SECOND_PHASE)
-				spi->mode |= SPI_CPHA;
+				lookup->mode |= SPI_CPHA;
 			if (sb->clock_polarity == ACPI_SPI_START_HIGH)
-				spi->mode |= SPI_CPOL;
+				lookup->mode |= SPI_CPOL;
 			if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH)
-				spi->mode |= SPI_CS_HIGH;
+				lookup->mode |= SPI_CS_HIGH;
 		}
-	} else if (spi->irq < 0) {
+	} else if (lookup->irq < 0) {
 		struct resource r;
 
 		if (acpi_dev_resource_interrupt(ares, 0, &r))
-			spi->irq = r.start;
+			lookup->irq = r.start;
 	}
 
 	/* Always tell the ACPI core to skip this resource */
@@ -1868,12 +2201,36 @@
 static acpi_status acpi_register_spi_device(struct spi_controller *ctlr,
 					    struct acpi_device *adev)
 {
+	acpi_handle parent_handle = NULL;
 	struct list_head resource_list;
+	struct acpi_spi_lookup lookup = {};
 	struct spi_device *spi;
 	int ret;
 
 	if (acpi_bus_get_status(adev) || !adev->status.present ||
 	    acpi_device_enumerated(adev))
+		return AE_OK;
+
+	lookup.ctlr		= ctlr;
+	lookup.irq		= -1;
+
+	INIT_LIST_HEAD(&resource_list);
+	ret = acpi_dev_get_resources(adev, &resource_list,
+				     acpi_spi_add_resource, &lookup);
+	acpi_dev_free_resource_list(&resource_list);
+
+	if (ret < 0)
+		/* found SPI in _CRS but it points to another controller */
+		return AE_OK;
+
+	if (!lookup.max_speed_hz &&
+	    !ACPI_FAILURE(acpi_get_parent(adev->handle, &parent_handle)) &&
+	    ACPI_HANDLE(ctlr->dev.parent) == parent_handle) {
+		/* Apple does not use _CRS but nested devices for SPI slaves */
+		acpi_spi_parse_apple_properties(adev, &lookup);
+	}
+
+	if (!lookup.max_speed_hz)
 		return AE_OK;
 
 	spi = spi_alloc_device(ctlr);
@@ -1883,20 +2240,13 @@
 		return AE_NO_MEMORY;
 	}
 
+
 	ACPI_COMPANION_SET(&spi->dev, adev);
-	spi->irq = -1;
-
-	INIT_LIST_HEAD(&resource_list);
-	ret = acpi_dev_get_resources(adev, &resource_list,
-				     acpi_spi_add_resource, spi);
-	acpi_dev_free_resource_list(&resource_list);
-
-	acpi_spi_parse_apple_properties(spi);
-
-	if (ret < 0 || !spi->max_speed_hz) {
-		spi_dev_put(spi);
-		return AE_OK;
-	}
+	spi->max_speed_hz	= lookup.max_speed_hz;
+	spi->mode		|= lookup.mode;
+	spi->irq		= lookup.irq;
+	spi->bits_per_word	= lookup.bits_per_word;
+	spi->chip_select	= lookup.chip_select;
 
 	acpi_set_modalias(adev, acpi_device_hid(adev), spi->modalias,
 			  sizeof(spi->modalias));
@@ -1929,6 +2279,8 @@
 	return acpi_register_spi_device(ctlr, adev);
 }
 
+#define SPI_ACPI_ENUMERATE_MAX_DEPTH		32
+
 static void acpi_register_spi_devices(struct spi_controller *ctlr)
 {
 	acpi_status status;
@@ -1938,7 +2290,8 @@
 	if (!handle)
 		return;
 
-	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
+	status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
+				     SPI_ACPI_ENUMERATE_MAX_DEPTH,
 				     acpi_spi_add_device, NULL, ctlr, NULL);
 	if (ACPI_FAILURE(status))
 		dev_warn(&ctlr->dev, "failed to enumerate SPI slaves\n");
@@ -1984,8 +2337,8 @@
 	return 1;
 }
 
-static ssize_t spi_slave_show(struct device *dev,
-			      struct device_attribute *attr, char *buf)
+static ssize_t slave_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
 {
 	struct spi_controller *ctlr = container_of(dev, struct spi_controller,
 						   dev);
@@ -1996,9 +2349,8 @@
 		       child ? to_spi_device(child)->modalias : NULL);
 }
 
-static ssize_t spi_slave_store(struct device *dev,
-			       struct device_attribute *attr, const char *buf,
-			       size_t count)
+static ssize_t slave_store(struct device *dev, struct device_attribute *attr,
+			   const char *buf, size_t count)
 {
 	struct spi_controller *ctlr = container_of(dev, struct spi_controller,
 						   dev);
@@ -2036,7 +2388,7 @@
 	return count;
 }
 
-static DEVICE_ATTR(slave, 0644, spi_slave_show, spi_slave_store);
+static DEVICE_ATTR_RW(slave);
 
 static struct attribute *spi_slave_attrs[] = {
 	&dev_attr_slave.attr,
@@ -2067,8 +2419,10 @@
  * __spi_alloc_controller - allocate an SPI master or slave controller
  * @dev: the controller, possibly using the platform_bus
  * @size: how much zeroed driver-private data to allocate; the pointer to this
- *	memory is in the driver_data field of the returned device,
- *	accessible with spi_controller_get_devdata().
+ *	memory is in the driver_data field of the returned device, accessible
+ *	with spi_controller_get_devdata(); the memory is cacheline aligned;
+ *	drivers granting DMA access to portions of their private data need to
+ *	round up @size using ALIGN(size, dma_get_cache_alignment()).
  * @slave: flag indicating whether to allocate an SPI master (false) or SPI
  *	slave (true) controller
  * Context: can sleep
@@ -2090,11 +2444,12 @@
 					      unsigned int size, bool slave)
 {
 	struct spi_controller	*ctlr;
+	size_t ctlr_size = ALIGN(sizeof(*ctlr), dma_get_cache_alignment());
 
 	if (!dev)
 		return NULL;
 
-	ctlr = kzalloc(size + sizeof(*ctlr), GFP_KERNEL);
+	ctlr = kzalloc(size + ctlr_size, GFP_KERNEL);
 	if (!ctlr)
 		return NULL;
 
@@ -2108,7 +2463,7 @@
 		ctlr->dev.class = &spi_master_class;
 	ctlr->dev.parent = dev;
 	pm_suspend_ignore_children(&ctlr->dev, true);
-	spi_controller_set_devdata(ctlr, &ctlr[1]);
+	spi_controller_set_devdata(ctlr, (void *)ctlr + ctlr_size);
 
 	return ctlr;
 }
@@ -2158,7 +2513,7 @@
 EXPORT_SYMBOL_GPL(__devm_spi_alloc_controller);
 
 #ifdef CONFIG_OF
-static int of_spi_register_master(struct spi_controller *ctlr)
+static int of_spi_get_gpio_numbers(struct spi_controller *ctlr)
 {
 	int nb, i, *cs;
 	struct device_node *np = ctlr->dev.of_node;
@@ -2191,11 +2546,85 @@
 	return 0;
 }
 #else
-static int of_spi_register_master(struct spi_controller *ctlr)
+static int of_spi_get_gpio_numbers(struct spi_controller *ctlr)
 {
 	return 0;
 }
 #endif
+
+/**
+ * spi_get_gpio_descs() - grab chip select GPIOs for the master
+ * @ctlr: The SPI master to grab GPIO descriptors for
+ */
+static int spi_get_gpio_descs(struct spi_controller *ctlr)
+{
+	int nb, i;
+	struct gpio_desc **cs;
+	struct device *dev = &ctlr->dev;
+	unsigned long native_cs_mask = 0;
+	unsigned int num_cs_gpios = 0;
+
+	nb = gpiod_count(dev, "cs");
+	ctlr->num_chipselect = max_t(int, nb, ctlr->num_chipselect);
+
+	/* No GPIOs at all is fine, else return the error */
+	if (nb == 0 || nb == -ENOENT)
+		return 0;
+	else if (nb < 0)
+		return nb;
+
+	cs = devm_kcalloc(dev, ctlr->num_chipselect, sizeof(*cs),
+			  GFP_KERNEL);
+	if (!cs)
+		return -ENOMEM;
+	ctlr->cs_gpiods = cs;
+
+	for (i = 0; i < nb; i++) {
+		/*
+		 * Most chipselects are active low, the inverted
+		 * semantics are handled by special quirks in gpiolib,
+		 * so initializing them GPIOD_OUT_LOW here means
+		 * "unasserted", in most cases this will drive the physical
+		 * line high.
+		 */
+		cs[i] = devm_gpiod_get_index_optional(dev, "cs", i,
+						      GPIOD_OUT_LOW);
+		if (IS_ERR(cs[i]))
+			return PTR_ERR(cs[i]);
+
+		if (cs[i]) {
+			/*
+			 * If we find a CS GPIO, name it after the device and
+			 * chip select line.
+			 */
+			char *gpioname;
+
+			gpioname = devm_kasprintf(dev, GFP_KERNEL, "%s CS%d",
+						  dev_name(dev), i);
+			if (!gpioname)
+				return -ENOMEM;
+			gpiod_set_consumer_name(cs[i], gpioname);
+			num_cs_gpios++;
+			continue;
+		}
+
+		if (ctlr->max_native_cs && i >= ctlr->max_native_cs) {
+			dev_err(dev, "Invalid native chip select %d\n", i);
+			return -EINVAL;
+		}
+		native_cs_mask |= BIT(i);
+	}
+
+	ctlr->unused_native_cs = ffs(~native_cs_mask) - 1;
+
+	if ((ctlr->flags & SPI_MASTER_GPIO_SS) && num_cs_gpios &&
+	    ctlr->max_native_cs && ctlr->unused_native_cs >= ctlr->max_native_cs) {
+		dev_err(dev, "No unused native chip select available\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
 
 static int spi_controller_check_ops(struct spi_controller *ctlr)
 {
@@ -2244,7 +2673,7 @@
 {
 	struct device		*dev = ctlr->dev.parent;
 	struct boardinfo	*bi;
-	int			status = -ENODEV;
+	int			status;
 	int			id, first_dynamic;
 
 	if (!dev)
@@ -2258,17 +2687,6 @@
 	if (status)
 		return status;
 
-	if (!spi_controller_is_slave(ctlr)) {
-		status = of_spi_register_master(ctlr);
-		if (status)
-			return status;
-	}
-
-	/* even if it's just one always-selected device, there must
-	 * be at least one chipselect
-	 */
-	if (ctlr->num_chipselect == 0)
-		return -EINVAL;
 	if (ctlr->bus_num >= 0) {
 		/* devices with a fixed bus num must check-in with the num */
 		mutex_lock(&board_lock);
@@ -2320,14 +2738,37 @@
 	 * registration fails if the bus ID is in use.
 	 */
 	dev_set_name(&ctlr->dev, "spi%u", ctlr->bus_num);
-	status = device_add(&ctlr->dev);
-	if (status < 0) {
-		/* free bus id */
-		mutex_lock(&board_lock);
-		idr_remove(&spi_master_idr, ctlr->bus_num);
-		mutex_unlock(&board_lock);
-		goto done;
+
+	if (!spi_controller_is_slave(ctlr)) {
+		if (ctlr->use_gpio_descriptors) {
+			status = spi_get_gpio_descs(ctlr);
+			if (status)
+				goto free_bus_id;
+			/*
+			 * A controller using GPIO descriptors always
+			 * supports SPI_CS_HIGH if need be.
+			 */
+			ctlr->mode_bits |= SPI_CS_HIGH;
+		} else {
+			/* Legacy code path for GPIOs from DT */
+			status = of_spi_get_gpio_numbers(ctlr);
+			if (status)
+				goto free_bus_id;
+		}
 	}
+
+	/*
+	 * Even if it's just one always-selected device, there must
+	 * be at least one chipselect.
+	 */
+	if (!ctlr->num_chipselect) {
+		status = -EINVAL;
+		goto free_bus_id;
+	}
+
+	status = device_add(&ctlr->dev);
+	if (status < 0)
+		goto free_bus_id;
 	dev_dbg(dev, "registered %s %s\n",
 			spi_controller_is_slave(ctlr) ? "slave" : "master",
 			dev_name(&ctlr->dev));
@@ -2343,11 +2784,7 @@
 		status = spi_controller_initialize_queue(ctlr);
 		if (status) {
 			device_del(&ctlr->dev);
-			/* free bus id */
-			mutex_lock(&board_lock);
-			idr_remove(&spi_master_idr, ctlr->bus_num);
-			mutex_unlock(&board_lock);
-			goto done;
+			goto free_bus_id;
 		}
 	}
 	/* add statistics */
@@ -2362,7 +2799,12 @@
 	/* Register devices from the device tree and ACPI */
 	of_register_spi_devices(ctlr);
 	acpi_register_spi_devices(ctlr);
-done:
+	return status;
+
+free_bus_id:
+	mutex_lock(&board_lock);
+	idr_remove(&spi_master_idr, ctlr->bus_num);
+	mutex_unlock(&board_lock);
 	return status;
 }
 EXPORT_SYMBOL_GPL(spi_register_controller);
@@ -2612,12 +3054,9 @@
  */
 void spi_res_release(struct spi_controller *ctlr, struct spi_message *message)
 {
-	struct spi_res *res;
+	struct spi_res *res, *tmp;
 
-	while (!list_empty(&message->resources)) {
-		res = list_last_entry(&message->resources,
-				      struct spi_res, entry);
-
+	list_for_each_entry_safe_reverse(res, tmp, &message->resources, entry) {
 		if (res->release)
 			res->release(ctlr, message, res->data);
 
@@ -2681,8 +3120,7 @@
 
 	/* allocate the structure using spi_res */
 	rxfer = spi_res_alloc(msg->spi, __spi_replace_transfers_release,
-			      insert * sizeof(struct spi_transfer)
-			      + sizeof(struct spi_replaced_transfers)
+			      struct_size(rxfer, inserted_transfers, insert)
 			      + extradatasize,
 			      gfp);
 	if (!rxfer)
@@ -2744,10 +3182,11 @@
 		/* add to list */
 		list_add(&xfer->transfer_list, rxfer->replaced_after);
 
-		/* clear cs_change and delay_usecs for all but the last */
+		/* clear cs_change and delay for all but the last */
 		if (i) {
 			xfer->cs_change = false;
 			xfer->delay_usecs = 0;
+			xfer->delay.value = 0;
 		}
 	}
 
@@ -2771,11 +3210,6 @@
 	struct spi_replaced_transfers *srt;
 	size_t offset;
 	size_t count, i;
-
-	/* warn once about this fact that we are splitting a transfer */
-	dev_warn_once(&msg->spi->dev,
-		      "spi_transfer of length %i exceed max length of %zu - needed to split transfers\n",
-		      xfer->len, maxsize);
 
 	/* calculate how many we have to replace */
 	count = DIV_ROUND_UP(xfer->len, maxsize);
@@ -2925,7 +3359,8 @@
 	/* if it is SPI_3WIRE mode, DUAL and QUAD should be forbidden
 	 */
 	if ((spi->mode & SPI_3WIRE) && (spi->mode &
-		(SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD)))
+		(SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL |
+		 SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL)))
 		return -EINVAL;
 	/* help drivers fail *cleanly* when they need options
 	 * that aren't supported with their current controller
@@ -2933,8 +3368,14 @@
 	 * so it is ignored here.
 	 */
 	bad_bits = spi->mode & ~(spi->controller->mode_bits | SPI_CS_WORD);
+	/* nothing prevents from working with active-high CS in case if it
+	 * is driven by GPIO.
+	 */
+	if (gpio_is_valid(spi->cs_gpio))
+		bad_bits &= ~SPI_CS_HIGH;
 	ugly_bits = bad_bits &
-		    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_RX_DUAL | SPI_RX_QUAD);
+		    (SPI_TX_DUAL | SPI_TX_QUAD | SPI_TX_OCTAL |
+		     SPI_RX_DUAL | SPI_RX_QUAD | SPI_RX_OCTAL);
 	if (ugly_bits) {
 		dev_warn(&spi->dev,
 			 "setup: ignoring unsupported mode bits %x\n",
@@ -2959,10 +3400,42 @@
 	if (!spi->max_speed_hz)
 		spi->max_speed_hz = spi->controller->max_speed_hz;
 
+	mutex_lock(&spi->controller->io_mutex);
+
 	if (spi->controller->setup)
 		status = spi->controller->setup(spi);
 
-	spi_set_cs(spi, false);
+	if (spi->controller->auto_runtime_pm && spi->controller->set_cs) {
+		status = pm_runtime_get_sync(spi->controller->dev.parent);
+		if (status < 0) {
+			mutex_unlock(&spi->controller->io_mutex);
+			pm_runtime_put_noidle(spi->controller->dev.parent);
+			dev_err(&spi->controller->dev, "Failed to power device: %d\n",
+				status);
+			return status;
+		}
+
+		/*
+		 * We do not want to return positive value from pm_runtime_get,
+		 * there are many instances of devices calling spi_setup() and
+		 * checking for a non-zero return value instead of a negative
+		 * return value.
+		 */
+		status = 0;
+
+		spi_set_cs(spi, false, true);
+		pm_runtime_mark_last_busy(spi->controller->dev.parent);
+		pm_runtime_put_autosuspend(spi->controller->dev.parent);
+	} else {
+		spi_set_cs(spi, false, true);
+	}
+
+	mutex_unlock(&spi->controller->io_mutex);
+
+	if (spi->rt && !spi->controller->rt) {
+		spi->controller->rt = true;
+		spi_set_thread_rt(spi->controller);
+	}
 
 	dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s%u bits/w, %u Hz max --> %d\n",
 			(int) (spi->mode & (SPI_CPOL | SPI_CPHA)),
@@ -2976,6 +3449,74 @@
 	return status;
 }
 EXPORT_SYMBOL_GPL(spi_setup);
+
+/**
+ * spi_set_cs_timing - configure CS setup, hold, and inactive delays
+ * @spi: the device that requires specific CS timing configuration
+ * @setup: CS setup time specified via @spi_delay
+ * @hold: CS hold time specified via @spi_delay
+ * @inactive: CS inactive delay between transfers specified via @spi_delay
+ *
+ * Return: zero on success, else a negative error code.
+ */
+int spi_set_cs_timing(struct spi_device *spi, struct spi_delay *setup,
+		      struct spi_delay *hold, struct spi_delay *inactive)
+{
+	size_t len;
+
+	if (spi->controller->set_cs_timing)
+		return spi->controller->set_cs_timing(spi, setup, hold,
+						      inactive);
+
+	if ((setup && setup->unit == SPI_DELAY_UNIT_SCK) ||
+	    (hold && hold->unit == SPI_DELAY_UNIT_SCK) ||
+	    (inactive && inactive->unit == SPI_DELAY_UNIT_SCK)) {
+		dev_err(&spi->dev,
+			"Clock-cycle delays for CS not supported in SW mode\n");
+		return -ENOTSUPP;
+	}
+
+	len = sizeof(struct spi_delay);
+
+	/* copy delays to controller */
+	if (setup)
+		memcpy(&spi->controller->cs_setup, setup, len);
+	else
+		memset(&spi->controller->cs_setup, 0, len);
+
+	if (hold)
+		memcpy(&spi->controller->cs_hold, hold, len);
+	else
+		memset(&spi->controller->cs_hold, 0, len);
+
+	if (inactive)
+		memcpy(&spi->controller->cs_inactive, inactive, len);
+	else
+		memset(&spi->controller->cs_inactive, 0, len);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(spi_set_cs_timing);
+
+static int _spi_xfer_word_delay_update(struct spi_transfer *xfer,
+				       struct spi_device *spi)
+{
+	int delay1, delay2;
+
+	delay1 = spi_delay_to_ns(&xfer->word_delay, xfer);
+	if (delay1 < 0)
+		return delay1;
+
+	delay2 = spi_delay_to_ns(&spi->word_delay, xfer);
+	if (delay2 < 0)
+		return delay2;
+
+	if (delay1 < delay2)
+		memcpy(&xfer->word_delay, &spi->word_delay,
+		       sizeof(xfer->word_delay));
+
+	return 0;
+}
 
 static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 {
@@ -2993,6 +3534,7 @@
 	 * cs_change is set for each transfer.
 	 */
 	if ((spi->mode & SPI_CS_WORD) && (!(ctlr->mode_bits & SPI_CS_WORD) ||
+					  spi->cs_gpiod ||
 					  gpio_is_valid(spi->cs_gpio))) {
 		size_t maxsize;
 		int ret;
@@ -3039,17 +3581,18 @@
 	 * it is not set for this transfer.
 	 * Set transfer tx_nbits and rx_nbits as single transfer default
 	 * (SPI_NBITS_SINGLE) if it is not set for this transfer.
+	 * Ensure transfer word_delay is at least as long as that required by
+	 * device itself.
 	 */
 	message->frame_length = 0;
 	list_for_each_entry(xfer, &message->transfers, transfer_list) {
+		xfer->effective_speed_hz = 0;
 		message->frame_length += xfer->len;
 		if (!xfer->bits_per_word)
 			xfer->bits_per_word = spi->bits_per_word;
 
 		if (!xfer->speed_hz)
 			xfer->speed_hz = spi->max_speed_hz;
-		if (!xfer->speed_hz)
-			xfer->speed_hz = ctlr->max_speed_hz;
 
 		if (ctlr->max_speed_hz && xfer->speed_hz > ctlr->max_speed_hz)
 			xfer->speed_hz = ctlr->max_speed_hz;
@@ -3109,6 +3652,9 @@
 				!(spi->mode & SPI_RX_QUAD))
 				return -EINVAL;
 		}
+
+		if (_spi_xfer_word_delay_update(xfer, spi))
+			return -EINVAL;
 	}
 
 	message->status = -EINPROGRESS;
@@ -3119,6 +3665,7 @@
 static int __spi_async(struct spi_device *spi, struct spi_message *message)
 {
 	struct spi_controller *ctlr = spi->controller;
+	struct spi_transfer *xfer;
 
 	/*
 	 * Some controllers do not support doing regular SPI transfers. Return
@@ -3133,6 +3680,13 @@
 	SPI_STATISTICS_INCREMENT_FIELD(&spi->statistics, spi_async);
 
 	trace_spi_message_submit(message);
+
+	if (!ctlr->ptp_sts_supported) {
+		list_for_each_entry(xfer, &message->transfers, transfer_list) {
+			xfer->ptp_sts_word_pre = 0;
+			ptp_read_system_prets(xfer->ptp_sts);
+		}
+	}
 
 	return ctlr->transfer(spi, message);
 }
@@ -3437,8 +3991,7 @@
  * is zero for success, else a negative errno status code.
  * This call may only be used from a context that may sleep.
  *
- * Parameters to this routine are always copied using a small buffer;
- * portable code should never use this for more than 32 bytes.
+ * Parameters to this routine are always copied using a small buffer.
  * Performance-sensitive or bulk transfer code should instead use
  * spi_{async,sync}() calls with dma-safe buffers.
  *
@@ -3501,37 +4054,25 @@
 /*-------------------------------------------------------------------------*/
 
 #if IS_ENABLED(CONFIG_OF)
-static int __spi_of_device_match(struct device *dev, void *data)
-{
-	return dev->of_node == data;
-}
-
 /* must call put_device() when done with returned spi_device device */
 struct spi_device *of_find_spi_device_by_node(struct device_node *node)
 {
-	struct device *dev = bus_find_device(&spi_bus_type, NULL, node,
-						__spi_of_device_match);
+	struct device *dev = bus_find_device_by_of_node(&spi_bus_type, node);
+
 	return dev ? to_spi_device(dev) : NULL;
 }
 EXPORT_SYMBOL_GPL(of_find_spi_device_by_node);
 #endif /* IS_ENABLED(CONFIG_OF) */
 
 #if IS_ENABLED(CONFIG_OF_DYNAMIC)
-static int __spi_of_controller_match(struct device *dev, const void *data)
-{
-	return dev->of_node == data;
-}
-
 /* the spi controllers are not using spi_bus, so we find it with another way */
 static struct spi_controller *of_find_spi_controller_by_node(struct device_node *node)
 {
 	struct device *dev;
 
-	dev = class_find_device(&spi_master_class, NULL, node,
-				__spi_of_controller_match);
+	dev = class_find_device_by_of_node(&spi_master_class, node);
 	if (!dev && IS_ENABLED(CONFIG_SPI_SLAVE))
-		dev = class_find_device(&spi_slave_class, NULL, node,
-					__spi_of_controller_match);
+		dev = class_find_device_by_of_node(&spi_slave_class, node);
 	if (!dev)
 		return NULL;
 
@@ -3602,11 +4143,6 @@
 	return ACPI_COMPANION(dev->parent) == data;
 }
 
-static int spi_acpi_device_match(struct device *dev, void *data)
-{
-	return ACPI_COMPANION(dev) == data;
-}
-
 static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev)
 {
 	struct device *dev;
@@ -3626,9 +4162,8 @@
 {
 	struct device *dev;
 
-	dev = bus_find_device(&spi_bus_type, NULL, adev, spi_acpi_device_match);
-
-	return dev ? to_spi_device(dev) : NULL;
+	dev = bus_find_device_by_acpi_dev(&spi_bus_type, adev);
+	return to_spi_device(dev);
 }
 
 static int acpi_spi_notify(struct notifier_block *nb, unsigned long value,
@@ -3720,4 +4255,3 @@
  * include needing to have boardinfo data structures be much more public.
  */
 postcore_initcall(spi_init);
-

--
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