/*
* spi.c - SPI init/core code
*
* Copyright (C) 2005 David Brownell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/init.h>
#include <linux/cache.h>
#include <linux/mutex.h>
#include <linux/slab.h>
#include <linux/mod_devicetable.h>
#include <linux/spi/spi.h>
#include <linux/of_spi.h>
/* SPI bustype and spi_master class are registered after board init code
* provides the SPI device tables, ensuring that both are present by the
* time controller driver registration causes spi_devices to "enumerate".
*/
static void spidev_release(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
/* spi masters may cleanup for released devices */
if (spi->master->cleanup)
spi->master->cleanup(spi);
spi_master_put(spi->master);
kfree(spi);
}
static ssize_t
modalias_show(struct device *dev, struct device_attribute *a, char *buf)
{
const struct spi_device *spi = to_spi_device(dev);
return sprintf(buf, "%s\n", spi->modalias);
}
static struct device_attribute spi_dev_attrs[] = {
__ATTR_RO(modalias),
__ATTR_NULL,
};
/* modalias support makes "modprobe $MODALIAS" new-style hotplug work,
* and the sysfs version makes coldplug work too.
*/
static const struct spi_device_id *spi_match_id(const struct spi_device_id *id,
const struct spi_device *sdev)
{
while (id->name[0]) {
if (!strcmp(sdev->modalias, id->name))
return id;
id++;
}
return NULL;
}
const struct spi_device_id *spi_get_device_id(const struct spi_device *sdev)
{
const struct spi_driver *sdrv = to_spi_driver(sdev->dev.driver);
return spi_match_id(sdrv->id_table, sdev);
}
EXPORT_SYMBOL_GPL(spi_get_device_id);
static int spi_match_device(struct device *dev, struct device_driver *drv)
{
const struct spi_device *spi = to_spi_device(dev);
const struct spi_driver *sdrv = to_spi_driver(drv);
if (sdrv->id_table)
return !!spi_match_id(sdrv->id_table, spi);
return strcmp(spi->modalias, drv->name) == 0;
}
static int spi_uevent(struct device *dev, struct kobj_uevent_env *env)
{
const struct spi_device *spi = to_spi_device(dev);
add_uevent_var(env, "MODALIAS=%s%s", SPI_MODULE_PREFIX, spi->modalias);
return 0;
}
#ifdef CONFIG_PM
static int spi_suspend(struct device *dev, pm_message_t message)
{
int value = 0;
struct spi_driver *drv = to_spi_driver(dev->driver);
/* suspend will stop irqs and dma; no more i/o */
if (drv) {
if (drv->suspend)
value = drv->suspend(to_spi_device(dev), message);
else
dev_dbg(dev, "... can't suspend\n");
}
return value;
}
static int spi_resume(struct device *dev)
{
int value = 0;
struct spi_driver *drv = to_spi_driver(dev->driver);
/* resume may restart the i/o queue */
if (drv) {
if (drv->resume)
value = drv->resume(to_spi_device(dev));
else
dev_dbg(dev, "... can't resume\n");
}
return value;
}
#else
#define spi_suspend NULL
#define spi_resume NULL
#endif
struct bus_type spi_bus_type = {
.name = "spi",
.dev_attrs = spi_dev_attrs,
.match = spi_match_device,
.uevent = spi_uevent,
.suspend = spi_suspend,
.resume = spi_resume,
};
EXPORT_SYMBOL_GPL(