From 87e59b36e5e26122efd55d77adb9fac827987db0 Mon Sep 17 00:00:00 2001 From: Stefan Binding Date: Fri, 21 Jan 2022 17:24:25 +0000 Subject: [PATCH] spi: Support selection of the index of the ACPI Spi Resource before alloc If a node contains more than one SPI resource it may be necessary to use an index to select which one you want to allocate a spi device for. Signed-off-by: Stefan Binding Reviewed-by: Hans de Goede Link: https://lore.kernel.org/r/20220121172431.6876-4-sbinding@opensource.cirrus.com Signed-off-by: Mark Brown --- drivers/spi/spi.c | 51 ++++++++++++++++++++++++++++++++++++++++++------- include/linux/spi/spi.h | 3 ++- 2 files changed, 46 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 13f4701f0694..06c0a308b38b 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -2320,6 +2320,8 @@ struct acpi_spi_lookup { int irq; u8 bits_per_word; u8 chip_select; + int n; + int index; }; static void acpi_spi_parse_apple_properties(struct acpi_device *dev, @@ -2351,6 +2353,8 @@ static void acpi_spi_parse_apple_properties(struct acpi_device *dev, lookup->mode |= SPI_CPHA; } +static struct spi_controller *acpi_spi_find_controller_by_adev(struct acpi_device *adev); + static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) { struct acpi_spi_lookup *lookup = data; @@ -2364,14 +2368,35 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) sb = &ares->data.spi_serial_bus; if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) { + if (lookup->index != -1 && lookup->n++ != lookup->index) + return 1; + + if (lookup->index == -1 && !ctlr) + return -ENODEV; + status = acpi_get_handle(NULL, sb->resource_source.string_ptr, &parent_handle); - if (ACPI_FAILURE(status) || - ACPI_HANDLE(ctlr->dev.parent) != parent_handle) + if (ACPI_FAILURE(status)) return -ENODEV; + if (ctlr) { + if (ACPI_HANDLE(ctlr->dev.parent) != parent_handle) + return -ENODEV; + } else { + struct acpi_device *adev; + + if (acpi_bus_get_device(parent_handle, &adev)) + return -ENODEV; + + ctlr = acpi_spi_find_controller_by_adev(adev); + if (!ctlr) + return -ENODEV; + + lookup->ctlr = ctlr; + } + /* * ACPI DeviceSelection numbering is handled by the * host controller driver in Windows and can vary @@ -2414,14 +2439,21 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) * acpi_spi_device_alloc - Allocate a spi device, and fill it in with ACPI information * @ctlr: controller to which the spi device belongs * @adev: ACPI Device for the spi device + * @index: Index of the spi resource inside the ACPI Node * * This should be used to allocate a new spi device from and ACPI Node. * The caller is responsible for calling spi_add_device to register the spi device. * + * If ctlr is set to NULL, the Controller for the spi device will be looked up + * using the resource. + * If index is set to -1, index is not used. + * Note: If index is -1, ctlr must be set. + * * Return: a pointer to the new device, or ERR_PTR on error. */ struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, - struct acpi_device *adev) + struct acpi_device *adev, + int index) { acpi_handle parent_handle = NULL; struct list_head resource_list; @@ -2429,8 +2461,13 @@ struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, struct spi_device *spi; int ret; + if (!ctlr && index == -1) + return ERR_PTR(-EINVAL); + lookup.ctlr = ctlr; lookup.irq = -1; + lookup.index = index; + lookup.n = 0; INIT_LIST_HEAD(&resource_list); ret = acpi_dev_get_resources(adev, &resource_list, @@ -2443,7 +2480,7 @@ struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, if (!lookup.max_speed_hz && ACPI_SUCCESS(acpi_get_parent(adev->handle, &parent_handle)) && - ACPI_HANDLE(ctlr->dev.parent) == parent_handle) { + ACPI_HANDLE(lookup.ctlr->dev.parent) == parent_handle) { /* Apple does not use _CRS but nested devices for SPI slaves */ acpi_spi_parse_apple_properties(adev, &lookup); } @@ -2451,9 +2488,9 @@ struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, if (!lookup.max_speed_hz) return ERR_PTR(-ENODEV); - spi = spi_alloc_device(ctlr); + spi = spi_alloc_device(lookup.ctlr); if (!spi) { - dev_err(&ctlr->dev, "failed to allocate SPI device for %s\n", + dev_err(&lookup.ctlr->dev, "failed to allocate SPI device for %s\n", dev_name(&adev->dev)); return ERR_PTR(-ENOMEM); } @@ -2478,7 +2515,7 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, acpi_device_enumerated(adev)) return AE_OK; - spi = acpi_spi_device_alloc(ctlr, adev); + spi = acpi_spi_device_alloc(ctlr, adev, -1); if (IS_ERR(spi)) { if (PTR_ERR(spi) == -ENOMEM) return AE_NO_MEMORY; diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h index d159cef12f1a..e5bbb9cbd3d7 100644 --- a/include/linux/spi/spi.h +++ b/include/linux/spi/spi.h @@ -762,7 +762,8 @@ extern void spi_unregister_controller(struct spi_controller *ctlr); #if IS_ENABLED(CONFIG_ACPI) extern struct spi_device *acpi_spi_device_alloc(struct spi_controller *ctlr, - struct acpi_device *adev); + struct acpi_device *adev, + int index); #endif /* -- 2.11.0