spi / ACPI: add ACPI enumeration support (64bee4d2) · Commits · 戴 / test

drivers/spi/spi.c

+102 −1

Original line number	Diff line number	Diff line
		@@ -35,6 +35,8 @@
		#include <linux/sched.h>
		#include <linux/delay.h>
		#include <linux/kthread.h>
		#include <linux/ioport.h>
		#include <linux/acpi.h>

		static void spidev_release(struct device *dev)
		{
		@@ -93,6 +95,10 @@ static int spi_match_device(struct device dev, struct device_driver drv)
		if (of_driver_match_device(dev, drv))
		return 1;

		/* Then try ACPI */
		if (acpi_driver_match_device(dev, drv))
		return 1;

		if (sdrv->id_table)
		return !!spi_match_id(sdrv->id_table, spi);

		@@ -888,6 +894,100 @@ static void of_register_spi_devices(struct spi_master *master)
		static void of_register_spi_devices(struct spi_master *master) { }
		#endif

		#ifdef CONFIG_ACPI
		static int acpi_spi_add_resource(struct acpi_resource ares, void data)
		{
		struct spi_device *spi = data;

		if (ares->type == ACPI_RESOURCE_TYPE_SERIAL_BUS) {
		struct acpi_resource_spi_serialbus *sb;

		sb = &ares->data.spi_serial_bus;
		if (sb->type == ACPI_RESOURCE_SERIAL_TYPE_SPI) {
		spi->chip_select = sb->device_selection;
		spi->max_speed_hz = sb->connection_speed;

		if (sb->clock_phase == ACPI_SPI_SECOND_PHASE)
		spi->mode \|= SPI_CPHA;
		if (sb->clock_polarity == ACPI_SPI_START_HIGH)
		spi->mode \|= SPI_CPOL;
		if (sb->device_polarity == ACPI_SPI_ACTIVE_HIGH)
		spi->mode \|= SPI_CS_HIGH;
		}
		} else if (spi->irq < 0) {
		struct resource r;

		if (acpi_dev_resource_interrupt(ares, 0, &r))
		spi->irq = r.start;
		}

		/* Always tell the ACPI core to skip this resource */
		return 1;
		}

		static acpi_status acpi_spi_add_device(acpi_handle handle, u32 level,
		void data, void *return_value)
		{
		struct spi_master *master = data;
		struct list_head resource_list;
		struct acpi_device *adev;
		struct spi_device *spi;
		int ret;

		if (acpi_bus_get_device(handle, &adev))
		return AE_OK;
		if (acpi_bus_get_status(adev) \|\| !adev->status.present)
		return AE_OK;

		spi = spi_alloc_device(master);
		if (!spi) {
		dev_err(&master->dev, "failed to allocate SPI device for %s\n",
		dev_name(&adev->dev));
		return AE_NO_MEMORY;
		}

		ACPI_HANDLE_SET(&spi->dev, handle);
		spi->irq = -1;

		INIT_LIST_HEAD(&resource_list);
		ret = acpi_dev_get_resources(adev, &resource_list,
		acpi_spi_add_resource, spi);
		acpi_dev_free_resource_list(&resource_list);

		if (ret < 0 \|\| !spi->max_speed_hz) {
		spi_dev_put(spi);
		return AE_OK;
		}

		strlcpy(spi->modalias, dev_name(&adev->dev), sizeof(spi->modalias));
		if (spi_add_device(spi)) {
		dev_err(&master->dev, "failed to add SPI device %s from ACPI\n",
		dev_name(&adev->dev));
		spi_dev_put(spi);
		}

		return AE_OK;
		}

		static void acpi_register_spi_devices(struct spi_master *master)
		{
		acpi_status status;
		acpi_handle handle;

		handle = ACPI_HANDLE(&master->dev);
		if (!handle)
		return;

		status = acpi_walk_namespace(ACPI_TYPE_DEVICE, handle, 1,
		acpi_spi_add_device, NULL,
		master, NULL);
		if (ACPI_FAILURE(status))
		dev_warn(&master->dev, "failed to enumerate SPI slaves\n");
		}
		#else
		static inline void acpi_register_spi_devices(struct spi_master *master) {}
		#endif /* CONFIG_ACPI */

		static void spi_master_release(struct device *dev)
		{
		struct spi_master *master;
		@@ -1023,8 +1123,9 @@ int spi_register_master(struct spi_master *master)
		spi_match_master_to_boardinfo(master, &bi->board_info);
		mutex_unlock(&board_lock);

		/* Register devices from the device tree */
		/* Register devices from the device tree and ACPI */
		of_register_spi_devices(master);
		acpi_register_spi_devices(master);
		done:
		return status;
		}

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