Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index f9502db..ac05c9c 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -47,10 +47,6 @@
 {
 	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);
 	kfree(spi);
@@ -405,9 +401,11 @@
 	if (ret)
 		return ret;
 
-	ret = sdrv->probe(spi);
-	if (ret)
-		dev_pm_domain_detach(dev, true);
+	if (sdrv->probe) {
+		ret = sdrv->probe(spi);
+		if (ret)
+			dev_pm_domain_detach(dev, true);
+	}
 
 	return ret;
 }
@@ -415,9 +413,10 @@
 static int spi_drv_remove(struct device *dev)
 {
 	const struct spi_driver		*sdrv = to_spi_driver(dev->driver);
-	int ret;
+	int ret = 0;
 
-	ret = sdrv->remove(to_spi_device(dev));
+	if (sdrv->remove)
+		ret = sdrv->remove(to_spi_device(dev));
 	dev_pm_domain_detach(dev, true);
 
 	return ret;
@@ -442,10 +441,8 @@
 {
 	sdrv->driver.owner = owner;
 	sdrv->driver.bus = &spi_bus_type;
-	if (sdrv->probe)
-		sdrv->driver.probe = spi_drv_probe;
-	if (sdrv->remove)
-		sdrv->driver.remove = spi_drv_remove;
+	sdrv->driver.probe = spi_drv_probe;
+	sdrv->driver.remove = spi_drv_remove;
 	if (sdrv->shutdown)
 		sdrv->driver.shutdown = spi_drv_shutdown;
 	return driver_register(&sdrv->driver);
@@ -475,6 +472,12 @@
  */
 static DEFINE_MUTEX(board_lock);
 
+/*
+ * Prevents addition of devices with same chip select and
+ * addition of devices below an unregistering controller.
+ */
+static DEFINE_MUTEX(spi_add_lock);
+
 /**
  * spi_alloc_device - Allocate a new SPI device
  * @ctlr: Controller to which device is connected
@@ -542,6 +545,12 @@
 	return 0;
 }
 
+static void spi_cleanup(struct spi_device *spi)
+{
+	if (spi->controller->cleanup)
+		spi->controller->cleanup(spi);
+}
+
 /**
  * spi_add_device - Add spi_device allocated with spi_alloc_device
  * @spi: spi_device to register
@@ -553,7 +562,6 @@
  */
 int spi_add_device(struct spi_device *spi)
 {
-	static DEFINE_MUTEX(spi_add_lock);
 	struct spi_controller *ctlr = spi->controller;
 	struct device *dev = ctlr->dev.parent;
 	int status;
@@ -581,6 +589,13 @@
 		goto done;
 	}
 
+	/* Controller may unregister concurrently */
+	if (IS_ENABLED(CONFIG_SPI_DYNAMIC) &&
+	    !device_is_registered(&ctlr->dev)) {
+		status = -ENODEV;
+		goto done;
+	}
+
 	/* Descriptors take precedence */
 	if (ctlr->cs_gpiods)
 		spi->cs_gpiod = ctlr->cs_gpiods[spi->chip_select];
@@ -600,11 +615,13 @@
 
 	/* 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);
@@ -697,7 +714,9 @@
 	}
 	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);
 
@@ -1229,8 +1248,6 @@
 	if (msg->status && ctlr->handle_err)
 		ctlr->handle_err(ctlr, msg);
 
-	spi_res_release(ctlr, msg);
-
 	spi_finalize_current_message(ctlr);
 
 	return ret;
@@ -1513,6 +1530,13 @@
 
 	spi_unmap_msg(ctlr, mesg);
 
+	/* In the prepare_messages callback the spi bus has the opportunity to
+	 * split a transfer to smaller chunks.
+	 * Release splited transfers here since spi_map_msg is done on the
+	 * splited transfers.
+	 */
+	spi_res_release(ctlr, mesg);
+
 	if (ctlr->cur_msg_prepared && ctlr->unprepare_message) {
 		ret = ctlr->unprepare_message(ctlr, mesg);
 		if (ret) {
@@ -1711,15 +1735,7 @@
 		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 +1799,15 @@
 	}
 	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) {
@@ -1824,6 +1849,7 @@
 	/* Store a pointer to the node in the device structure */
 	of_node_get(nc);
 	spi->dev.of_node = nc;
+	spi->dev.fwnode = of_fwnode_handle(nc);
 
 	/* Register the new device */
 	rc = spi_add_device(spi);
@@ -1949,6 +1975,7 @@
 			}
 
 			lookup->max_speed_hz = sb->connection_speed;
+			lookup->bits_per_word = sb->data_bit_length;
 
 			if (sb->clock_phase == ACPI_SPI_SECOND_PHASE)
 				lookup->mode |= SPI_CPHA;
@@ -2238,6 +2265,50 @@
 }
 EXPORT_SYMBOL_GPL(__spi_alloc_controller);
 
+static void devm_spi_release_controller(struct device *dev, void *ctlr)
+{
+	spi_controller_put(*(struct spi_controller **)ctlr);
+}
+
+/**
+ * __devm_spi_alloc_controller - resource-managed __spi_alloc_controller()
+ * @dev: physical device of SPI controller
+ * @size: how much zeroed driver-private data to allocate
+ * @slave: whether to allocate an SPI master (false) or SPI slave (true)
+ * Context: can sleep
+ *
+ * Allocate an SPI controller and automatically release a reference on it
+ * when @dev is unbound from its driver.  Drivers are thus relieved from
+ * having to call spi_controller_put().
+ *
+ * The arguments to this function are identical to __spi_alloc_controller().
+ *
+ * Return: the SPI controller structure on success, else NULL.
+ */
+struct spi_controller *__devm_spi_alloc_controller(struct device *dev,
+						   unsigned int size,
+						   bool slave)
+{
+	struct spi_controller **ptr, *ctlr;
+
+	ptr = devres_alloc(devm_spi_release_controller, sizeof(*ptr),
+			   GFP_KERNEL);
+	if (!ptr)
+		return NULL;
+
+	ctlr = __spi_alloc_controller(dev, size, slave);
+	if (ctlr) {
+		ctlr->devm_allocated = true;
+		*ptr = ctlr;
+		devres_add(dev, ptr);
+	} else {
+		devres_free(ptr);
+	}
+
+	return ctlr;
+}
+EXPORT_SYMBOL_GPL(__devm_spi_alloc_controller);
+
 #ifdef CONFIG_OF
 static int of_spi_get_gpio_numbers(struct spi_controller *ctlr)
 {
@@ -2451,7 +2522,7 @@
 		if (ctlr->use_gpio_descriptors) {
 			status = spi_get_gpio_descs(ctlr);
 			if (status)
-				return status;
+				goto free_bus_id;
 			/*
 			 * A controller using GPIO descriptors always
 			 * supports SPI_CS_HIGH if need be.
@@ -2461,7 +2532,7 @@
 			/* Legacy code path for GPIOs from DT */
 			status = of_spi_get_gpio_numbers(ctlr);
 			if (status)
-				return status;
+				goto free_bus_id;
 		}
 	}
 
@@ -2469,17 +2540,14 @@
 	 * Even if it's just one always-selected device, there must
 	 * be at least one chipselect.
 	 */
-	if (!ctlr->num_chipselect)
-		return -EINVAL;
+	if (!ctlr->num_chipselect) {
+		status = -EINVAL;
+		goto free_bus_id;
+	}
 
 	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 (status < 0)
+		goto free_bus_id;
 	dev_dbg(dev, "registered %s %s\n",
 			spi_controller_is_slave(ctlr) ? "slave" : "master",
 			dev_name(&ctlr->dev));
@@ -2495,11 +2563,7 @@
 		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 */
@@ -2514,7 +2578,12 @@
 	/* 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);
@@ -2582,6 +2651,12 @@
 	struct spi_controller *found;
 	int id = ctlr->bus_num;
 
+	/* Prevent addition of new devices, unregister existing ones */
+	if (IS_ENABLED(CONFIG_SPI_DYNAMIC))
+		mutex_lock(&spi_add_lock);
+
+	device_for_each_child(&ctlr->dev, NULL, __unregister);
+
 	/* First make sure that this controller was ever added */
 	mutex_lock(&board_lock);
 	found = idr_find(&spi_master_idr, id);
@@ -2594,13 +2669,22 @@
 	list_del(&ctlr->list);
 	mutex_unlock(&board_lock);
 
-	device_for_each_child(&ctlr->dev, NULL, __unregister);
-	device_unregister(&ctlr->dev);
+	device_del(&ctlr->dev);
+
+	/* Release the last reference on the controller if its driver
+	 * has not yet been converted to devm_spi_alloc_master/slave().
+	 */
+	if (!ctlr->devm_allocated)
+		put_device(&ctlr->dev);
+
 	/* free bus id */
 	mutex_lock(&board_lock);
 	if (found == ctlr)
 		idr_remove(&spi_master_idr, id);
 	mutex_unlock(&board_lock);
+
+	if (IS_ENABLED(CONFIG_SPI_DYNAMIC))
+		mutex_unlock(&spi_add_lock);
 }
 EXPORT_SYMBOL_GPL(spi_unregister_controller);