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.
This commit is contained in:
Mark Brown 2022-02-01 17:39:36 +00:00
commit 70ee8d48f4
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GPG Key ID: 24D68B725D5487D0
2 changed files with 141 additions and 16 deletions

View File

@ -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));

View File

@ -16,6 +16,7 @@
#include <linux/gpio/consumer.h>
#include <uapi/linux/spi/spi.h>
#include <linux/acpi.h>
struct dma_chan;
struct software_node;
@ -759,6 +760,13 @@ extern int devm_spi_register_controller(struct device *dev,
struct spi_controller *ctlr);
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,
int index);
int acpi_spi_count_resources(struct acpi_device *adev);
#endif
/*
* SPI resource management while processing a SPI message
*/
@ -1452,7 +1460,19 @@ spi_register_board_info(struct spi_board_info const *info, unsigned n)
* use spi_new_device() to describe each device. You can also call
* spi_unregister_device() to start making that device vanish, but
* normally that would be handled by spi_unregister_controller().
*
* You can also use spi_alloc_device() and spi_add_device() to use a two
* stage registration sequence for each spi_device. This gives the caller
* some more control over the spi_device structure before it is registered,
* but requires that caller to initialize fields that would otherwise
* be defined using the board info.
*/
extern struct spi_device *
spi_alloc_device(struct spi_controller *ctlr);
extern int
spi_add_device(struct spi_device *spi);
extern struct spi_device *
spi_new_device(struct spi_controller *, struct spi_board_info *);