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author | Mark Brown <broonie@kernel.org> | 2022-02-01 17:39:36 +0000 |
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committer | Mark Brown <broonie@kernel.org> | 2022-02-01 17:39:36 +0000 |
commit | 70ee8d48f465b0e8dbbfe38f4c854ffa2aeb06ba (patch) | |
tree | e7d2a436c5083f0d09426e2eeb8a432d38713d6d /drivers/spi | |
parent | b651d1da86aa525c5a5b2bd61f528353c28d589d (diff) | |
parent | e612af7acef2459f1afd885f4107748995a05963 (diff) | |
download | linux-stable-70ee8d48f465b0e8dbbfe38f4c854ffa2aeb06ba.tar.gz linux-stable-70ee8d48f465b0e8dbbfe38f4c854ffa2aeb06ba.tar.bz2 linux-stable-70ee8d48f465b0e8dbbfe38f4c854ffa2aeb06ba.zip |
spi: Enhance and export helpers for ACPI resources
Merge series from Stefan Binding <sbinding@opensource.cirrus.com>:
This series enhances the helpers for ACPI resources to cope with
multiple resources and exports them for use in the x86 platform code's
multi-instantiate driver.
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi.c | 137 |
1 files changed, 121 insertions, 16 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index 4599b121d744..ec9f2ed579e3 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -532,7 +532,7 @@ static DEFINE_MUTEX(board_lock); * * Return: a pointer to the new device, or NULL. */ -static struct spi_device *spi_alloc_device(struct spi_controller *ctlr) +struct spi_device *spi_alloc_device(struct spi_controller *ctlr) { struct spi_device *spi; @@ -557,6 +557,7 @@ static struct spi_device *spi_alloc_device(struct spi_controller *ctlr) device_initialize(&spi->dev); return spi; } +EXPORT_SYMBOL_GPL(spi_alloc_device); static void spi_dev_set_name(struct spi_device *spi) { @@ -652,7 +653,7 @@ static int __spi_add_device(struct spi_device *spi) * * Return: 0 on success; negative errno on failure */ -static int spi_add_device(struct spi_device *spi) +int spi_add_device(struct spi_device *spi) { struct spi_controller *ctlr = spi->controller; struct device *dev = ctlr->dev.parent; @@ -673,6 +674,7 @@ static int spi_add_device(struct spi_device *spi) mutex_unlock(&ctlr->add_lock); return status; } +EXPORT_SYMBOL_GPL(spi_add_device); static int spi_add_device_locked(struct spi_device *spi) { @@ -2318,8 +2320,50 @@ struct acpi_spi_lookup { int irq; u8 bits_per_word; u8 chip_select; + int n; + int index; }; +static int acpi_spi_count(struct acpi_resource *ares, void *data) +{ + struct acpi_resource_spi_serialbus *sb; + int *count = data; + + if (ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) + return 1; + + sb = &ares->data.spi_serial_bus; + if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_SPI) + return 1; + + *count = *count + 1; + + return 1; +} + +/** + * acpi_spi_count_resources - Count the number of SpiSerialBus resources + * @adev: ACPI device + * + * Returns the number of SpiSerialBus resources in the ACPI-device's + * resource-list; or a negative error code. + */ +int acpi_spi_count_resources(struct acpi_device *adev) +{ + LIST_HEAD(r); + int count = 0; + int ret; + + ret = acpi_dev_get_resources(adev, &r, acpi_spi_count, &count); + if (ret < 0) + return ret; + + acpi_dev_free_resource_list(&r); + + return count; +} +EXPORT_SYMBOL_GPL(acpi_spi_count_resources); + static void acpi_spi_parse_apple_properties(struct acpi_device *dev, struct acpi_spi_lookup *lookup) { @@ -2349,6 +2393,8 @@ 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; @@ -2362,14 +2408,35 @@ 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 @@ -2408,8 +2475,25 @@ static int acpi_spi_add_resource(struct acpi_resource *ares, void *data) return 1; } -static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, - struct acpi_device *adev) +/** + * 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, + int index) { acpi_handle parent_handle = NULL; struct list_head resource_list; @@ -2417,12 +2501,13 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, struct spi_device *spi; int ret; - if (acpi_bus_get_status(adev) || !adev->status.present || - acpi_device_enumerated(adev)) - return AE_OK; + 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, @@ -2431,26 +2516,25 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, if (ret < 0) /* found SPI in _CRS but it points to another controller */ - return AE_OK; + return ERR_PTR(-ENODEV); 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); } if (!lookup.max_speed_hz) - return AE_OK; + 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 AE_NO_MEMORY; + return ERR_PTR(-ENOMEM); } - ACPI_COMPANION_SET(&spi->dev, adev); spi->max_speed_hz = lookup.max_speed_hz; spi->mode |= lookup.mode; @@ -2458,6 +2542,27 @@ static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, spi->bits_per_word = lookup.bits_per_word; spi->chip_select = lookup.chip_select; + return spi; +} +EXPORT_SYMBOL_GPL(acpi_spi_device_alloc); + +static acpi_status acpi_register_spi_device(struct spi_controller *ctlr, + struct acpi_device *adev) +{ + struct spi_device *spi; + + if (acpi_bus_get_status(adev) || !adev->status.present || + acpi_device_enumerated(adev)) + return AE_OK; + + spi = acpi_spi_device_alloc(ctlr, adev, -1); + if (IS_ERR(spi)) { + if (PTR_ERR(spi) == -ENOMEM) + return AE_NO_MEMORY; + else + return AE_OK; + } + acpi_set_modalias(adev, acpi_device_hid(adev), spi->modalias, sizeof(spi->modalias)); |