1 files changed, 293 insertions, 39 deletions

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index f9502dbbb5c1..5e4c4532f7f3 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -92,7 +92,7 @@ static ssize_t driver_override_store(struct device *dev,
 	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 +469,7 @@ static LIST_HEAD(board_list);
 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
  */
@@ -775,6 +775,15 @@ int spi_register_board_info(struct spi_board_info const *info, unsigned n)
 
 static void spi_set_cs(struct spi_device *spi, bool enable)
 {
+	bool enable1 = enable;
+
+	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;
 
@@ -800,6 +809,11 @@ static void spi_set_cs(struct spi_device *spi, bool 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);
+	}
 }
 
 #ifdef CONFIG_HAS_DMA
@@ -1106,42 +1120,79 @@ static void _spi_transfer_delay_ns(u32 ns)
 	}
 }
 
-static void _spi_transfer_cs_change_delay(struct spi_message *msg,
-					  struct spi_transfer *xfer)
+int spi_delay_to_ns(struct spi_delay *_delay, struct spi_transfer *xfer)
 {
-	u32 delay = xfer->cs_change_delay;
-	u32 unit = xfer->cs_change_delay_unit;
+	u32 delay = _delay->value;
+	u32 unit = _delay->unit;
 	u32 hz;
 
-	/* return early on "fast" mode - for everything but USECS */
-	if (!delay && unit != SPI_DELAY_UNIT_USECS)
-		return;
+	if (!delay)
+		return 0;
 
 	switch (unit) {
 	case SPI_DELAY_UNIT_USECS:
-		/* for compatibility use default of 10us */
-		if (!delay)
-			delay = 10000;
-		else
-			delay *= 1000;
+		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;
+
+	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",
-			     xfer->cs_change_delay_unit);
-		delay = 10000;
+			     unit);
+		_spi_transfer_delay_ns(10000);
 	}
-	/* now sleep for the requested amount of time */
-	_spi_transfer_delay_ns(delay);
 }
 
 /*
@@ -1171,6 +1222,11 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
 		spi_statistics_add_transfer_stats(statm, xfer, ctlr);
 		spi_statistics_add_transfer_stats(stats, xfer, ctlr);
 
+		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) {
 			reinit_completion(&ctlr->xfer_completion);
 
@@ -1197,13 +1253,17 @@ static int spi_transfer_one_message(struct spi_controller *ctlr,
 					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)
-			_spi_transfer_delay_ns(xfer->delay_usecs * 1000);
+		spi_transfer_delay_exec(xfer);
 
 		if (xfer->cs_change) {
 			if (list_is_last(&xfer->transfer_list,
@@ -1265,6 +1325,7 @@ EXPORT_SYMBOL_GPL(spi_finalize_current_transfer);
  */
 static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread)
 {
+	struct spi_transfer *xfer;
 	struct spi_message *msg;
 	bool was_busy = false;
 	unsigned long flags;
@@ -1391,6 +1452,13 @@ static void __spi_pump_messages(struct spi_controller *ctlr, bool in_kthread)
 		goto out;
 	}
 
+	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,
@@ -1419,6 +1487,99 @@ static void spi_pump_messages(struct kthread_work *work)
 }
 
 /**
+ * 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
+ * @tx: Pointer to the current word within the xfer->tx_buf that the driver is
+ *	preparing to transmit right now.
+ * @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,
+			    const void *tx, bool irqs_off)
+{
+	u8 bytes_per_word = DIV_ROUND_UP(xfer->bits_per_word, 8);
+
+	if (!xfer->ptp_sts)
+		return;
+
+	if (xfer->timestamped_pre)
+		return;
+
+	if (tx < (xfer->tx_buf + xfer->ptp_sts_word_pre * bytes_per_word))
+		return;
+
+	/* Capture the resolution of the timestamp */
+	xfer->ptp_sts_word_pre = (tx - xfer->tx_buf) / bytes_per_word;
+
+	xfer->timestamped_pre = true;
+
+	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
+ * @tx: Pointer to the current word within the xfer->tx_buf that the driver has
+ *	just transmitted.
+ * @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,
+			     const void *tx, bool irqs_off)
+{
+	u8 bytes_per_word = DIV_ROUND_UP(xfer->bits_per_word, 8);
+
+	if (!xfer->ptp_sts)
+		return;
+
+	if (xfer->timestamped_post)
+		return;
+
+	if (tx < (xfer->tx_buf + xfer->ptp_sts_word_post * bytes_per_word))
+		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 = (tx - xfer->tx_buf) / bytes_per_word;
+
+	xfer->timestamped_post = 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
  *
@@ -1503,6 +1664,7 @@ EXPORT_SYMBOL_GPL(spi_get_next_queued_message);
  */
 void spi_finalize_current_message(struct spi_controller *ctlr)
 {
+	struct spi_transfer *xfer;
 	struct spi_message *mesg;
 	unsigned long flags;
 	int ret;
@@ -1511,6 +1673,13 @@ void spi_finalize_current_message(struct spi_controller *ctlr)
 	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;
+		}
+	}
+
 	spi_unmap_msg(ctlr, mesg);
 
 	if (ctlr->cur_msg_prepared && ctlr->unprepare_message) {
@@ -1711,15 +1880,7 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
 		spi->mode |= SPI_3WIRE;
 	if (of_property_read_bool(nc, "spi-lsb-first"))
 		spi->mode |= SPI_LSB_FIRST;
-
-	/*
-	 * For descriptors associated with the device, polarity inversion is
-	 * handled in the gpiolib, so all chip selects are "active high" in
-	 * the logical sense, the gpiolib will invert the line if need be.
-	 */
-	if (ctlr->use_gpio_descriptors)
-		spi->mode |= SPI_CS_HIGH;
-	else if (of_property_read_bool(nc, "spi-cs-high"))
+	if (of_property_read_bool(nc, "spi-cs-high"))
 		spi->mode |= SPI_CS_HIGH;
 
 	/* Device DUAL/QUAD mode */
@@ -1783,6 +1944,15 @@ static int of_spi_parse_dt(struct spi_controller *ctlr, struct spi_device *spi,
 	}
 	spi->chip_select = value;
 
+	/*
+	 * For descriptors associated with the device, polarity inversion is
+	 * handled in the gpiolib, so all gpio chip selects are "active high"
+	 * in the logical sense, the gpiolib will invert the line if need be.
+	 */
+	if ((ctlr->use_gpio_descriptors) && ctlr->cs_gpiods &&
+	    ctlr->cs_gpiods[spi->chip_select])
+		spi->mode |= SPI_CS_HIGH;
+
 	/* Device speed */
 	rc = of_property_read_u32(nc, "spi-max-frequency", &value);
 	if (rc) {
@@ -2871,10 +3041,11 @@ struct spi_replaced_transfers *spi_replace_transfers(
 		/* 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;
 		}
 	}
 
@@ -3091,7 +3262,29 @@ int spi_setup(struct spi_device *spi)
 	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) {
+			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);
+		pm_runtime_mark_last_busy(spi->controller->dev.parent);
+		pm_runtime_put_autosuspend(spi->controller->dev.parent);
+	} else {
+		spi_set_cs(spi, false);
+	}
 
 	if (spi->rt && !spi->controller->rt) {
 		spi->controller->rt = true;
@@ -3114,18 +3307,71 @@ 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 in terms of clock count
- * @hold: CS hold time in terms of clock count
- * @inactive_dly: CS inactive delay between transfers in terms of clock count
+ * @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.
  */
-void spi_set_cs_timing(struct spi_device *spi, u8 setup, u8 hold,
-		       u8 inactive_dly)
+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)
-		spi->controller->set_cs_timing(spi, setup, hold, inactive_dly);
+		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)
 {
 	struct spi_controller *ctlr = spi->controller;
@@ -3261,8 +3507,8 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 				return -EINVAL;
 		}
 
-		if (xfer->word_delay_usecs < spi->word_delay_usecs)
-			xfer->word_delay_usecs = spi->word_delay_usecs;
+		if (_spi_xfer_word_delay_update(xfer, spi))
+			return -EINVAL;
 	}
 
 	message->status = -EINPROGRESS;
@@ -3273,6 +3519,7 @@ static int __spi_validate(struct spi_device *spi, struct spi_message *message)
 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
@@ -3288,6 +3535,13 @@ static int __spi_async(struct spi_device *spi, struct spi_message *message)
 
 	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);
 }