Update Linux to v5.10.109

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz

Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 7067f85..e1d8863 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -13,6 +13,7 @@
 #include <linux/completion.h>
 #include <linux/scatterlist.h>
 #include <linux/gpio/consumer.h>
+#include <linux/ptp_clock_kernel.h>
 
 struct dma_chan;
 struct property_entry;
@@ -90,6 +91,22 @@
 	SPI_STATISTICS_ADD_TO_FIELD(stats, field, 1)
 
 /**
+ * struct spi_delay - SPI delay information
+ * @value: Value for the delay
+ * @unit: Unit for the delay
+ */
+struct spi_delay {
+#define SPI_DELAY_UNIT_USECS	0
+#define SPI_DELAY_UNIT_NSECS	1
+#define SPI_DELAY_UNIT_SCK	2
+	u16	value;
+	u8	unit;
+};
+
+extern int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer);
+extern int spi_delay_exec(struct spi_delay *_delay, struct spi_transfer *xfer);
+
+/**
  * struct spi_device - Controller side proxy for an SPI slave device
  * @dev: Driver model representation of the device.
  * @controller: SPI controller used with the device.
@@ -118,12 +135,14 @@
  * @modalias: Name of the driver to use with this device, or an alias
  *	for that name.  This appears in the sysfs "modalias" attribute
  *	for driver coldplugging, and in uevents used for hotplugging
+ * @driver_override: If the name of a driver is written to this attribute, then
+ *	the device will bind to the named driver and only the named driver.
  * @cs_gpio: LEGACY: gpio number of the chipselect line (optional, -ENOENT when
  *	not using a GPIO line) use cs_gpiod in new drivers by opting in on
  *	the spi_master.
  * @cs_gpiod: gpio descriptor of the chipselect line (optional, NULL when
  *	not using a GPIO line)
- * @word_delay_usecs: microsecond delay to be inserted between consecutive
+ * @word_delay: delay to be inserted between consecutive
  *	words of a transfer
  *
  * @statistics: statistics for the spi_device
@@ -173,7 +192,7 @@
 	const char		*driver_override;
 	int			cs_gpio;	/* LEGACY: chip select gpio */
 	struct gpio_desc	*cs_gpiod;	/* chip select gpio desc */
-	uint8_t			word_delay_usecs; /* inter-word delay */
+	struct spi_delay	word_delay; /* inter-word delay */
 
 	/* the statistics */
 	struct spi_statistics	statistics;
@@ -310,6 +329,7 @@
  *	every chipselect is connected to a slave.
  * @dma_alignment: SPI controller constraint on DMA buffers alignment.
  * @mode_bits: flags understood by this controller driver
+ * @buswidth_override_bits: flags to override for this controller driver
  * @bits_per_word_mask: A mask indicating which values of bits_per_word are
  *	supported by the driver. Bit n indicates that a bits_per_word n+1 is
  *	supported. If set, the SPI core will reject any transfer with an
@@ -339,8 +359,7 @@
  * @cleanup: frees controller-specific state
  * @can_dma: determine whether this controller supports DMA
  * @queued: whether this controller is providing an internal message queue
- * @kworker: thread struct for message pump
- * @kworker_task: pointer to task for message pump kworker thread
+ * @kworker: pointer to thread struct for message pump
  * @pump_messages: work struct for scheduling work to the message pump
  * @queue_lock: spinlock to syncronise access to message queue
  * @queue: message queue
@@ -349,6 +368,8 @@
  * @cur_msg_prepared: spi_prepare_message was called for the currently
  *                    in-flight message
  * @cur_msg_mapped: message has been mapped for DMA
+ * @last_cs_enable: was enable true on the last call to set_cs.
+ * @last_cs_mode_high: was (mode & SPI_CS_HIGH) true on the last call to set_cs.
  * @xfer_completion: used by core transfer_one_message()
  * @busy: message pump is busy
  * @running: message pump is running
@@ -375,6 +396,7 @@
  *                   for example doing DMA mapping.  Called from threaded
  *                   context.
  * @transfer_one: transfer a single spi_transfer.
+ *
  *                  - return 0 if the transfer is finished,
  *                  - return 1 if the transfer is still in progress. When
  *                    the driver is finished with this transfer it must
@@ -390,6 +412,11 @@
  *	     controller has native support for memory like operations.
  * @unprepare_message: undo any work done by prepare_message().
  * @slave_abort: abort the ongoing transfer request on an SPI slave controller
+ * @cs_setup: delay to be introduced by the controller after CS is asserted
+ * @cs_hold: delay to be introduced by the controller before CS is deasserted
+ * @cs_inactive: delay to be introduced by the controller after CS is
+ *	deasserted. If @cs_change_delay is used from @spi_transfer, then the
+ *	two delays will be added up.
  * @cs_gpios: LEGACY: array of GPIO descs to use as chip select lines; one per
  *	CS number. Any individual value may be -ENOENT for CS lines that
  *	are not GPIOs (driven by the SPI controller itself). Use the cs_gpiods
@@ -401,6 +428,12 @@
  *	GPIO descriptors rather than using global GPIO numbers grabbed by the
  *	driver. This will fill in @cs_gpiods and @cs_gpios should not be used,
  *	and SPI devices will have the cs_gpiod assigned rather than cs_gpio.
+ * @unused_native_cs: When cs_gpiods is used, spi_register_controller() will
+ *	fill in this field with the first unused native CS, to be used by SPI
+ *	controller drivers that need to drive a native CS when using GPIO CS.
+ * @max_native_cs: When cs_gpiods is used, and this field is filled in,
+ *	spi_register_controller() will validate all native CS (including the
+ *	unused native CS) against this value.
  * @statistics: statistics for the spi_controller
  * @dma_tx: DMA transmit channel
  * @dma_rx: DMA receive channel
@@ -409,6 +442,15 @@
  * @fw_translate_cs: If the boot firmware uses different numbering scheme
  *	what Linux expects, this optional hook can be used to translate
  *	between the two.
+ * @ptp_sts_supported: If the driver sets this to true, it must provide a
+ *	time snapshot in @spi_transfer->ptp_sts as close as possible to the
+ *	moment in time when @spi_transfer->ptp_sts_word_pre and
+ *	@spi_transfer->ptp_sts_word_post were transmitted.
+ *	If the driver does not set this, the SPI core takes the snapshot as
+ *	close to the driver hand-over as possible.
+ * @irq_flags: Interrupt enable state during PTP system timestamping
+ * @fallback: fallback to pio if dma transfer return failure with
+ *	SPI_TRANS_FAIL_NO_START.
  *
  * Each SPI controller can communicate with one or more @spi_device
  * children.  These make a small bus, sharing MOSI, MISO and SCK signals
@@ -447,6 +489,9 @@
 	/* spi_device.mode flags understood by this controller driver */
 	u32			mode_bits;
 
+	/* spi_device.mode flags override flags for this controller */
+	u32			buswidth_override_bits;
+
 	/* bitmask of supported bits_per_word for transfers */
 	u32			bits_per_word_mask;
 #define SPI_BPW_MASK(bits) BIT((bits) - 1)
@@ -505,8 +550,8 @@
 	 * to configure specific CS timing through spi_set_cs_timing() after
 	 * spi_setup().
 	 */
-	void (*set_cs_timing)(struct spi_device *spi, u8 setup_clk_cycles,
-			      u8 hold_clk_cycles, u8 inactive_clk_cycles);
+	int (*set_cs_timing)(struct spi_device *spi, struct spi_delay *setup,
+			     struct spi_delay *hold, struct spi_delay *inactive);
 
 	/* bidirectional bulk transfers
 	 *
@@ -551,8 +596,7 @@
 	 * Over time we expect SPI drivers to be phased over to this API.
 	 */
 	bool				queued;
-	struct kthread_worker		kworker;
-	struct task_struct		*kworker_task;
+	struct kthread_worker		*kworker;
 	struct kthread_work		pump_messages;
 	spinlock_t			queue_lock;
 	struct list_head		queue;
@@ -564,6 +608,9 @@
 	bool				auto_runtime_pm;
 	bool                            cur_msg_prepared;
 	bool				cur_msg_mapped;
+	bool				last_cs_enable;
+	bool				last_cs_mode_high;
+	bool                            fallback;
 	struct completion               xfer_completion;
 	size_t				max_dma_len;
 
@@ -590,10 +637,17 @@
 	/* Optimized handlers for SPI memory-like operations. */
 	const struct spi_controller_mem_ops *mem_ops;
 
+	/* CS delays */
+	struct spi_delay	cs_setup;
+	struct spi_delay	cs_hold;
+	struct spi_delay	cs_inactive;
+
 	/* gpio chip select */
 	int			*cs_gpios;
 	struct gpio_desc	**cs_gpiods;
 	bool			use_gpio_descriptors;
+	s8			unused_native_cs;
+	s8			max_native_cs;
 
 	/* statistics */
 	struct spi_statistics	statistics;
@@ -607,6 +661,15 @@
 	void			*dummy_tx;
 
 	int (*fw_translate_cs)(struct spi_controller *ctlr, unsigned cs);
+
+	/*
+	 * Driver sets this field to indicate it is able to snapshot SPI
+	 * transfers (needed e.g. for reading the time of POSIX clocks)
+	 */
+	bool			ptp_sts_supported;
+
+	/* Interrupt enable state during PTP system timestamping */
+	unsigned long		irq_flags;
 };
 
 static inline void *spi_controller_get_devdata(struct spi_controller *ctlr)
@@ -647,6 +710,14 @@
 extern void spi_finalize_current_message(struct spi_controller *ctlr);
 extern void spi_finalize_current_transfer(struct spi_controller *ctlr);
 
+/* Helper calls for driver to timestamp transfer */
+void spi_take_timestamp_pre(struct spi_controller *ctlr,
+			    struct spi_transfer *xfer,
+			    size_t progress, bool irqs_off);
+void spi_take_timestamp_post(struct spi_controller *ctlr,
+			     struct spi_transfer *xfer,
+			     size_t progress, bool irqs_off);
+
 /* the spi driver core manages memory for the spi_controller classdev */
 extern struct spi_controller *__spi_alloc_controller(struct device *host,
 						unsigned int size, bool slave);
@@ -761,13 +832,13 @@
  * @cs_change: affects chipselect after this transfer completes
  * @cs_change_delay: delay between cs deassert and assert when
  *      @cs_change is set and @spi_transfer is not the last in @spi_message
- * @cs_change_delay_unit: unit of cs_change_delay
+ * @delay: delay to be introduced after this transfer before
+ *	(optionally) changing the chipselect status, then starting
+ *	the next transfer or completing this @spi_message.
  * @delay_usecs: microseconds to delay after this transfer before
  *	(optionally) changing the chipselect status, then starting
  *	the next transfer or completing this @spi_message.
- * @word_delay_usecs: microseconds to inter word delay after each word size
- *	(set by bits_per_word) transmission.
- * @word_delay: clock cycles to inter word delay after each word size
+ * @word_delay: inter word delay to be introduced after each word size
  *	(set by bits_per_word) transmission.
  * @effective_speed_hz: the effective SCK-speed that was used to
  *      transfer this transfer. Set to 0 if the spi bus driver does
@@ -775,6 +846,31 @@
  * @transfer_list: transfers are sequenced through @spi_message.transfers
  * @tx_sg: Scatterlist for transmit, currently not for client use
  * @rx_sg: Scatterlist for receive, currently not for client use
+ * @ptp_sts_word_pre: The word (subject to bits_per_word semantics) offset
+ *	within @tx_buf for which the SPI device is requesting that the time
+ *	snapshot for this transfer begins. Upon completing the SPI transfer,
+ *	this value may have changed compared to what was requested, depending
+ *	on the available snapshotting resolution (DMA transfer,
+ *	@ptp_sts_supported is false, etc).
+ * @ptp_sts_word_post: See @ptp_sts_word_post. The two can be equal (meaning
+ *	that a single byte should be snapshotted).
+ *	If the core takes care of the timestamp (if @ptp_sts_supported is false
+ *	for this controller), it will set @ptp_sts_word_pre to 0, and
+ *	@ptp_sts_word_post to the length of the transfer. This is done
+ *	purposefully (instead of setting to spi_transfer->len - 1) to denote
+ *	that a transfer-level snapshot taken from within the driver may still
+ *	be of higher quality.
+ * @ptp_sts: Pointer to a memory location held by the SPI slave device where a
+ *	PTP system timestamp structure may lie. If drivers use PIO or their
+ *	hardware has some sort of assist for retrieving exact transfer timing,
+ *	they can (and should) assert @ptp_sts_supported and populate this
+ *	structure using the ptp_read_system_*ts helper functions.
+ *	The timestamp must represent the time at which the SPI slave device has
+ *	processed the word, i.e. the "pre" timestamp should be taken before
+ *	transmitting the "pre" word, and the "post" timestamp after receiving
+ *	transmit confirmation from the controller for the "post" word.
+ * @timestamped: true if the transfer has been timestamped
+ * @error: Error status logged by spi controller driver.
  *
  * SPI transfers always write the same number of bytes as they read.
  * Protocol drivers should always provide @rx_buf and/or @tx_buf.
@@ -852,19 +948,25 @@
 #define	SPI_NBITS_DUAL		0x02 /* 2bits transfer */
 #define	SPI_NBITS_QUAD		0x04 /* 4bits transfer */
 	u8		bits_per_word;
-	u8		word_delay_usecs;
 	u16		delay_usecs;
-	u16		cs_change_delay;
-	u8		cs_change_delay_unit;
-#define SPI_DELAY_UNIT_USECS	0
-#define SPI_DELAY_UNIT_NSECS	1
-#define SPI_DELAY_UNIT_SCK	2
+	struct spi_delay	delay;
+	struct spi_delay	cs_change_delay;
+	struct spi_delay	word_delay;
 	u32		speed_hz;
-	u16		word_delay;
 
 	u32		effective_speed_hz;
 
+	unsigned int	ptp_sts_word_pre;
+	unsigned int	ptp_sts_word_post;
+
+	struct ptp_system_timestamp *ptp_sts;
+
+	bool		timestamped;
+
 	struct list_head transfer_list;
+
+#define SPI_TRANS_FAIL_NO_START	BIT(0)
+	u16		error;
 };
 
 /**
@@ -887,7 +989,7 @@
  * each represented by a struct spi_transfer.  The sequence is "atomic"
  * in the sense that no other spi_message may use that SPI bus until that
  * sequence completes.  On some systems, many such sequences can execute as
- * as single programmed DMA transfer.  On all systems, these messages are
+ * a single programmed DMA transfer.  On all systems, these messages are
  * queued, and might complete after transactions to other devices.  Messages
  * sent to a given spi_device are always executed in FIFO order.
  *
@@ -957,6 +1059,20 @@
 	list_del(&t->transfer_list);
 }
 
+static inline int
+spi_transfer_delay_exec(struct spi_transfer *t)
+{
+	struct spi_delay d;
+
+	if (t->delay_usecs) {
+		d.value = t->delay_usecs;
+		d.unit = SPI_DELAY_UNIT_USECS;
+		return spi_delay_exec(&d, NULL);
+	}
+
+	return spi_delay_exec(&t->delay, t);
+}
+
 /**
  * spi_message_init_with_transfers - Initialize spi_message and append transfers
  * @m: spi_message to be initialized
@@ -1004,7 +1120,10 @@
 	kfree(m);
 }
 
-extern void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold, u8 inactive_dly);
+extern int spi_set_cs_timing(struct spi_device *spi,
+			     struct spi_delay *setup,
+			     struct spi_delay *hold,
+			     struct spi_delay *inactive);
 
 extern int spi_setup(struct spi_device *spi);
 extern int spi_async(struct spi_device *spi, struct spi_message *message);
@@ -1133,7 +1252,7 @@
  *
  * For more specific semantics see spi_sync().
  *
- * Return: Return: zero on success, else a negative error code.
+ * Return: zero on success, else a negative error code.
  */
 static inline int
 spi_sync_transfer(struct spi_device *spi, struct spi_transfer *xfers,