u-boot/drivers/spi/sandbox_spi.c

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/*
* Simulate a SPI port
*
* Copyright (c) 2011-2013 The Chromium OS Authors.
* See file CREDITS for list of people who contributed to this
* project.
*
* Licensed under the GPL-2 or later.
*/
#define LOG_CATEGORY UCLASS_SPI
#include <common.h>
#include <dm.h>
#include <log.h>
#include <malloc.h>
#include <spi.h>
#include <spi_flash.h>
#include <os.h>
#include <linux/errno.h>
#include <asm/spi.h>
#include <asm/state.h>
#include <dm/acpi.h>
#include <dm/device-internal.h>
#ifndef CONFIG_SPI_IDLE_VAL
# define CONFIG_SPI_IDLE_VAL 0xFF
#endif
/**
* struct sandbox_spi_priv - Sandbox SPI private data
*
* Helper struct to keep track of the sandbox SPI bus internal state. It is
* used in unit tests to verify that dm spi functions update the bus
* speed/mode properly (for instance, when jumping back and forth between spi
* slaves claiming the bus, we need to make sure that the bus speed is updated
* accordingly for each slave).
*
* @speed: Current bus speed.
* @mode: Current bus mode.
*/
struct sandbox_spi_priv {
uint speed;
uint mode;
};
__weak int sandbox_spi_get_emul(struct sandbox_state *state,
struct udevice *bus, struct udevice *slave,
struct udevice **emulp)
{
return -ENOENT;
}
uint sandbox_spi_get_speed(struct udevice *dev)
{
struct sandbox_spi_priv *priv = dev_get_priv(dev);
return priv->speed;
}
uint sandbox_spi_get_mode(struct udevice *dev)
{
struct sandbox_spi_priv *priv = dev_get_priv(dev);
return priv->mode;
}
static int sandbox_spi_xfer(struct udevice *slave, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
struct udevice *bus = slave->parent;
struct sandbox_state *state = state_get_current();
struct dm_spi_emul_ops *ops;
struct udevice *emul;
uint bytes = bitlen / 8, i;
int ret;
uint busnum, cs;
if (bitlen == 0)
return 0;
/* we can only do 8 bit transfers */
if (bitlen % 8) {
printf("sandbox_spi: xfer: invalid bitlen size %u; needs to be 8bit\n",
bitlen);
return -EINVAL;
}
busnum = dev_seq(bus);
cs = spi_chip_select(slave);
if (busnum >= CONFIG_SANDBOX_SPI_MAX_BUS ||
cs >= CONFIG_SANDBOX_SPI_MAX_CS) {
printf("%s: busnum=%u, cs=%u: out of range\n", __func__,
busnum, cs);
return -ENOENT;
}
ret = sandbox_spi_get_emul(state, bus, slave, &emul);
if (ret) {
printf("%s: busnum=%u, cs=%u: no emulation available (err=%d)\n",
__func__, busnum, cs, ret);
return -ENOENT;
}
ret = device_probe(emul);
if (ret)
return ret;
ops = spi_emul_get_ops(emul);
ret = ops->xfer(emul, bitlen, dout, din, flags);
log_content("sandbox_spi: xfer: got back %i (that's %s)\n rx:",
ret, ret ? "bad" : "good");
if (din) {
for (i = 0; i < bytes; ++i)
log_content(" %u:%02x", i, ((u8 *)din)[i]);
}
log_content("\n");
return ret;
}
static int sandbox_spi_set_speed(struct udevice *bus, uint speed)
{
struct sandbox_spi_priv *priv = dev_get_priv(bus);
priv->speed = speed;
return 0;
}
static int sandbox_spi_set_mode(struct udevice *bus, uint mode)
{
struct sandbox_spi_priv *priv = dev_get_priv(bus);
priv->mode = mode;
return 0;
}
static int sandbox_cs_info(struct udevice *bus, uint cs,
struct spi_cs_info *info)
{
/* Always allow activity on CS 0, CS 1 */
if (cs >= 2)
return -EINVAL;
return 0;
}
static int sandbox_spi_get_mmap(struct udevice *dev, ulong *map_basep,
uint *map_sizep, uint *offsetp)
{
*map_basep = 0x1000;
*map_sizep = 0x2000;
*offsetp = 0x100;
return 0;
}
static const struct dm_spi_ops sandbox_spi_ops = {
.xfer = sandbox_spi_xfer,
.set_speed = sandbox_spi_set_speed,
.set_mode = sandbox_spi_set_mode,
.cs_info = sandbox_cs_info,
.get_mmap = sandbox_spi_get_mmap,
};
static const struct udevice_id sandbox_spi_ids[] = {
{ .compatible = "sandbox,spi" },
{ }
};
U_BOOT_DRIVER(sandbox_spi) = {
.name = "sandbox_spi",
.id = UCLASS_SPI,
.of_match = sandbox_spi_ids,
.ops = &sandbox_spi_ops,
.priv_auto = sizeof(struct sandbox_spi_priv),
};