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Merge branch 'acpi-enumeration'

* acpi-enumeration:
  spi / ACPI: add ACPI enumeration support
  gpio / ACPI: add ACPI support
Rafael J. Wysocki 12 years ago
parent
commit
d9ba1025a4
5 changed files with 180 additions and 1 deletions
  1. 4 0
      drivers/gpio/Kconfig
  2. 1 0
      drivers/gpio/Makefile
  3. 54 0
      drivers/gpio/gpiolib-acpi.c
  4. 102 1
      drivers/spi/spi.c
  5. 19 0
      include/linux/acpi_gpio.h

+ 4 - 0
drivers/gpio/Kconfig

@@ -49,6 +49,10 @@ config OF_GPIO
 	def_bool y
 	depends on OF
 
+config GPIO_ACPI
+	def_bool y
+	depends on ACPI
+
 config DEBUG_GPIO
 	bool "Debug GPIO calls"
 	depends on DEBUG_KERNEL

+ 1 - 0
drivers/gpio/Makefile

@@ -4,6 +4,7 @@ ccflags-$(CONFIG_DEBUG_GPIO)	+= -DDEBUG
 
 obj-$(CONFIG_GPIOLIB)		+= gpiolib.o devres.o
 obj-$(CONFIG_OF_GPIO)		+= gpiolib-of.o
+obj-$(CONFIG_GPIO_ACPI)		+= gpiolib-acpi.o
 
 # Device drivers. Generally keep list sorted alphabetically
 obj-$(CONFIG_GPIO_GENERIC)	+= gpio-generic.o

+ 54 - 0
drivers/gpio/gpiolib-acpi.c

@@ -0,0 +1,54 @@
+/*
+ * ACPI helpers for GPIO API
+ *
+ * Copyright (C) 2012, Intel Corporation
+ * Authors: Mathias Nyman <mathias.nyman@linux.intel.com>
+ *          Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/errno.h>
+#include <linux/gpio.h>
+#include <linux/export.h>
+#include <linux/acpi_gpio.h>
+#include <linux/acpi.h>
+
+static int acpi_gpiochip_find(struct gpio_chip *gc, void *data)
+{
+	if (!gc->dev)
+		return false;
+
+	return ACPI_HANDLE(gc->dev) == data;
+}
+
+/**
+ * acpi_get_gpio() - Translate ACPI GPIO pin to GPIO number usable with GPIO API
+ * @path:	ACPI GPIO controller full path name, (e.g. "\\_SB.GPO1")
+ * @pin:	ACPI GPIO pin number (0-based, controller-relative)
+ *
+ * Returns GPIO number to use with Linux generic GPIO API, or errno error value
+ */
+
+int acpi_get_gpio(char *path, int pin)
+{
+	struct gpio_chip *chip;
+	acpi_handle handle;
+	acpi_status status;
+
+	status = acpi_get_handle(NULL, path, &handle);
+	if (ACPI_FAILURE(status))
+		return -ENODEV;
+
+	chip = gpiochip_find(handle, acpi_gpiochip_find);
+	if (!chip)
+		return -ENODEV;
+
+	if (!gpio_is_valid(chip->base + pin))
+		return -EINVAL;
+
+	return chip->base + pin;
+}
+EXPORT_SYMBOL_GPL(acpi_get_gpio);

+ 102 - 1
drivers/spi/spi.c

@@ -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;
 }

+ 19 - 0
include/linux/acpi_gpio.h

@@ -0,0 +1,19 @@
+#ifndef _LINUX_ACPI_GPIO_H_
+#define _LINUX_ACPI_GPIO_H_
+
+#include <linux/errno.h>
+
+#ifdef CONFIG_GPIO_ACPI
+
+int acpi_get_gpio(char *path, int pin);
+
+#else /* CONFIG_GPIO_ACPI */
+
+static inline int acpi_get_gpio(char *path, int pin)
+{
+	return -ENODEV;
+}
+
+#endif /* CONFIG_GPIO_ACPI */
+
+#endif /* _LINUX_ACPI_GPIO_H_ */