u-boot/drivers/spi/spi-uclass.c

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/*
* Copyright (c) 2014 Google, Inc
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <fdtdec.h>
#include <malloc.h>
#include <spi.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#include <dm/root.h>
#include <dm/lists.h>
#include <dm/util.h>
DECLARE_GLOBAL_DATA_PTR;
static int spi_set_speed_mode(struct udevice *bus, int speed, int mode)
{
struct dm_spi_ops *ops;
int ret;
ops = spi_get_ops(bus);
if (ops->set_speed)
ret = ops->set_speed(bus, speed);
else
ret = -EINVAL;
if (ret) {
printf("Cannot set speed (err=%d)\n", ret);
return ret;
}
if (ops->set_mode)
ret = ops->set_mode(bus, mode);
else
ret = -EINVAL;
if (ret) {
printf("Cannot set mode (err=%d)\n", ret);
return ret;
}
return 0;
}
int spi_claim_bus(struct spi_slave *slave)
{
struct udevice *dev = slave->dev;
struct udevice *bus = dev->parent;
struct dm_spi_ops *ops = spi_get_ops(bus);
struct dm_spi_bus *spi = bus->uclass_priv;
int speed;
int ret;
speed = slave->max_hz;
if (spi->max_hz) {
if (speed)
speed = min(speed, (int)spi->max_hz);
else
speed = spi->max_hz;
}
if (!speed)
speed = 100000;
ret = spi_set_speed_mode(bus, speed, slave->mode);
if (ret)
return ret;
return ops->claim_bus ? ops->claim_bus(bus) : 0;
}
void spi_release_bus(struct spi_slave *slave)
{
struct udevice *dev = slave->dev;
struct udevice *bus = dev->parent;
struct dm_spi_ops *ops = spi_get_ops(bus);
if (ops->release_bus)
ops->release_bus(bus);
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct udevice *dev = slave->dev;
struct udevice *bus = dev->parent;
if (bus->uclass->uc_drv->id != UCLASS_SPI)
return -EOPNOTSUPP;
return spi_get_ops(bus)->xfer(dev, bitlen, dout, din, flags);
}
int spi_post_bind(struct udevice *dev)
{
/* Scan the bus for devices */
return dm_scan_fdt_node(dev, gd->fdt_blob, dev->of_offset, false);
}
int spi_post_probe(struct udevice *dev)
{
struct dm_spi_bus *spi = dev->uclass_priv;
spi->max_hz = fdtdec_get_int(gd->fdt_blob, dev->of_offset,
"spi-max-frequency", 0);
return 0;
}
int spi_chip_select(struct udevice *dev)
{
struct spi_slave *slave = dev_get_parentdata(dev);
return slave ? slave->cs : -ENOENT;
}
int spi_find_chip_select(struct udevice *bus, int cs, struct udevice **devp)
{
struct udevice *dev;
for (device_find_first_child(bus, &dev); dev;
device_find_next_child(&dev)) {
struct spi_slave store;
struct spi_slave *slave = dev_get_parentdata(dev);
if (!slave) {
slave = &store;
spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset,
slave);
}
debug("%s: slave=%p, cs=%d\n", __func__, slave,
slave ? slave->cs : -1);
if (slave && slave->cs == cs) {
*devp = dev;
return 0;
}
}
return -ENODEV;
}
int spi_cs_is_valid(unsigned int busnum, unsigned int cs)
{
struct spi_cs_info info;
struct udevice *bus;
int ret;
ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
if (ret) {
debug("%s: No bus %d\n", __func__, busnum);
return ret;
}
return spi_cs_info(bus, cs, &info);
}
int spi_cs_info(struct udevice *bus, uint cs, struct spi_cs_info *info)
{
struct spi_cs_info local_info;
struct dm_spi_ops *ops;
int ret;
if (!info)
info = &local_info;
/* If there is a device attached, return it */
info->dev = NULL;
ret = spi_find_chip_select(bus, cs, &info->dev);
if (!ret)
return 0;
/*
* Otherwise ask the driver. For the moment we don't have CS info.
* When we do we could provide the driver with a helper function
* to figure out what chip selects are valid, or just handle the
* request.
*/
ops = spi_get_ops(bus);
if (ops->cs_info)
return ops->cs_info(bus, cs, info);
/*
* We could assume there is at least one valid chip select, but best
* to be sure and return an error in this case. The driver didn't
* care enough to tell us.
*/
return -ENODEV;
}
int spi_find_bus_and_cs(int busnum, int cs, struct udevice **busp,
struct udevice **devp)
{
struct udevice *bus, *dev;
int ret;
ret = uclass_find_device_by_seq(UCLASS_SPI, busnum, false, &bus);
if (ret) {
debug("%s: No bus %d\n", __func__, busnum);
return ret;
}
ret = spi_find_chip_select(bus, cs, &dev);
if (ret) {
debug("%s: No cs %d\n", __func__, cs);
return ret;
}
*busp = bus;
*devp = dev;
return ret;
}
int spi_get_bus_and_cs(int busnum, int cs, int speed, int mode,
const char *drv_name, const char *dev_name,
struct udevice **busp, struct spi_slave **devp)
{
struct udevice *bus, *dev;
struct spi_slave *slave;
bool created = false;
int ret;
ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
if (ret) {
printf("Invalid bus %d (err=%d)\n", busnum, ret);
return ret;
}
ret = spi_find_chip_select(bus, cs, &dev);
/*
* If there is no such device, create one automatically. This means
* that we don't need a device tree node or platform data for the
* SPI flash chip - we will bind to the correct driver.
*/
if (ret == -ENODEV && drv_name) {
debug("%s: Binding new device '%s', busnum=%d, cs=%d, driver=%s\n",
__func__, dev_name, busnum, cs, drv_name);
ret = device_bind_driver(bus, drv_name, dev_name, &dev);
if (ret)
return ret;
created = true;
} else if (ret) {
printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
ret);
return ret;
}
if (!device_active(dev)) {
slave = (struct spi_slave *)calloc(1,
sizeof(struct spi_slave));
if (!slave) {
ret = -ENOMEM;
goto err;
}
ret = spi_ofdata_to_platdata(gd->fdt_blob, dev->of_offset,
slave);
if (ret)
goto err;
slave->cs = cs;
slave->dev = dev;
ret = device_probe_child(dev, slave);
free(slave);
if (ret)
goto err;
}
ret = spi_set_speed_mode(bus, speed, mode);
if (ret)
goto err;
*busp = bus;
*devp = dev_get_parentdata(dev);
debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
return 0;
err:
if (created) {
device_remove(dev);
device_unbind(dev);
}
return ret;
}
/* Compatibility function - to be removed */
struct spi_slave *spi_setup_slave_fdt(const void *blob, int node,
int bus_node)
{
struct udevice *bus, *dev;
int ret;
ret = uclass_get_device_by_of_offset(UCLASS_SPI, bus_node, &bus);
if (ret)
return NULL;
ret = device_get_child_by_of_offset(bus, node, &dev);
if (ret)
return NULL;
return dev_get_parentdata(dev);
}
/* Compatibility function - to be removed */
struct spi_slave *spi_setup_slave(unsigned int busnum, unsigned int cs,
unsigned int speed, unsigned int mode)
{
struct spi_slave *slave;
struct udevice *dev;
int ret;
ret = spi_get_bus_and_cs(busnum, cs, speed, mode, NULL, 0, &dev,
&slave);
if (ret)
return NULL;
return slave;
}
void spi_free_slave(struct spi_slave *slave)
{
device_remove(slave->dev);
slave->dev = NULL;
}
int spi_ofdata_to_platdata(const void *blob, int node,
struct spi_slave *spi)
{
int mode = 0;
spi->cs = fdtdec_get_int(blob, node, "reg", -1);
spi->max_hz = fdtdec_get_int(blob, node, "spi-max-frequency", 0);
if (fdtdec_get_bool(blob, node, "spi-cpol"))
mode |= SPI_CPOL;
if (fdtdec_get_bool(blob, node, "spi-cpha"))
mode |= SPI_CPHA;
if (fdtdec_get_bool(blob, node, "spi-cs-high"))
mode |= SPI_CS_HIGH;
if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
mode |= SPI_PREAMBLE;
spi->mode = mode;
return 0;
}
UCLASS_DRIVER(spi) = {
.id = UCLASS_SPI,
.name = "spi",
.post_bind = spi_post_bind,
.post_probe = spi_post_probe,
.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
};
UCLASS_DRIVER(spi_generic) = {
.id = UCLASS_SPI_GENERIC,
.name = "spi_generic",
};
U_BOOT_DRIVER(spi_generic_drv) = {
.name = "spi_generic_drv",
.id = UCLASS_SPI_GENERIC,
};