u-boot/drivers/spi/spi-uclass.c
Jagan Teki 8473b32127 spi: Add spi_write_then_read
Add support for SPI synchronous write followed by read,
this is common interface call from spi-nor to spi drivers.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Tested-by: Adam Ford <aford173@gmail.com> #da850-evm
2019-09-16 08:09:22 +05:30

486 lines
11 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2014 Google, Inc
*/
#include <common.h>
#include <dm.h>
#include <errno.h>
#include <malloc.h>
#include <spi.h>
#include <dm/device-internal.h>
#include <dm/uclass-internal.h>
#include <dm/lists.h>
#include <dm/util.h>
DECLARE_GLOBAL_DATA_PTR;
#define SPI_DEFAULT_SPEED_HZ 100000
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 dm_spi_claim_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct dm_spi_ops *ops = spi_get_ops(bus);
struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
struct spi_slave *slave = dev_get_parent_priv(dev);
int speed;
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 = SPI_DEFAULT_SPEED_HZ;
if (speed != slave->speed) {
int ret = spi_set_speed_mode(bus, speed, slave->mode);
if (ret)
return log_ret(ret);
slave->speed = speed;
}
return log_ret(ops->claim_bus ? ops->claim_bus(dev) : 0);
}
void dm_spi_release_bus(struct udevice *dev)
{
struct udevice *bus = dev->parent;
struct dm_spi_ops *ops = spi_get_ops(bus);
if (ops->release_bus)
ops->release_bus(dev);
}
int dm_spi_xfer(struct udevice *dev, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
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_claim_bus(struct spi_slave *slave)
{
return log_ret(dm_spi_claim_bus(slave->dev));
}
void spi_release_bus(struct spi_slave *slave)
{
dm_spi_release_bus(slave->dev);
}
int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
const void *dout, void *din, unsigned long flags)
{
return dm_spi_xfer(slave->dev, bitlen, dout, din, flags);
}
int spi_write_then_read(struct spi_slave *slave, const u8 *opcode,
size_t n_opcode, const u8 *txbuf, u8 *rxbuf,
size_t n_buf)
{
unsigned long flags = SPI_XFER_BEGIN;
int ret;
if (n_buf == 0)
flags |= SPI_XFER_END;
ret = spi_xfer(slave, n_opcode * 8, opcode, NULL, flags);
if (ret) {
debug("spi: failed to send command (%zu bytes): %d\n",
n_opcode, ret);
} else if (n_buf != 0) {
ret = spi_xfer(slave, n_buf * 8, txbuf, rxbuf, SPI_XFER_END);
if (ret)
debug("spi: failed to transfer %zu bytes of data: %d\n",
n_buf, ret);
}
return ret;
}
#if !CONFIG_IS_ENABLED(OF_PLATDATA)
static int spi_child_post_bind(struct udevice *dev)
{
struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
if (!dev_of_valid(dev))
return 0;
return spi_slave_ofdata_to_platdata(dev, plat);
}
#endif
static int spi_post_probe(struct udevice *bus)
{
#if !CONFIG_IS_ENABLED(OF_PLATDATA)
struct dm_spi_bus *spi = dev_get_uclass_priv(bus);
spi->max_hz = dev_read_u32_default(bus, "spi-max-frequency", 0);
#endif
#if defined(CONFIG_NEEDS_MANUAL_RELOC)
struct dm_spi_ops *ops = spi_get_ops(bus);
if (ops->claim_bus)
ops->claim_bus += gd->reloc_off;
if (ops->release_bus)
ops->release_bus += gd->reloc_off;
if (ops->set_wordlen)
ops->set_wordlen += gd->reloc_off;
if (ops->xfer)
ops->xfer += gd->reloc_off;
if (ops->set_speed)
ops->set_speed += gd->reloc_off;
if (ops->set_mode)
ops->set_mode += gd->reloc_off;
if (ops->cs_info)
ops->cs_info += gd->reloc_off;
#endif
return 0;
}
static int spi_child_pre_probe(struct udevice *dev)
{
struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
struct spi_slave *slave = dev_get_parent_priv(dev);
/*
* This is needed because we pass struct spi_slave around the place
* instead slave->dev (a struct udevice). So we have to have some
* way to access the slave udevice given struct spi_slave. Once we
* change the SPI API to use udevice instead of spi_slave, we can
* drop this.
*/
slave->dev = dev;
slave->max_hz = plat->max_hz;
slave->mode = plat->mode;
slave->wordlen = SPI_DEFAULT_WORDLEN;
return 0;
}
int spi_chip_select(struct udevice *dev)
{
struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev);
return plat ? plat->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 dm_spi_slave_platdata *plat;
plat = dev_get_parent_platdata(dev);
debug("%s: plat=%p, cs=%d\n", __func__, plat, plat->cs);
if (plat->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 dm_spi_slave_platdata *plat;
bool created = false;
int ret;
#if CONFIG_IS_ENABLED(OF_PLATDATA) || CONFIG_IS_ENABLED(OF_PRIOR_STAGE)
ret = uclass_first_device_err(UCLASS_SPI, &bus);
#else
ret = uclass_get_device_by_seq(UCLASS_SPI, busnum, &bus);
#endif
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) {
debug("%s: Unable to bind driver (ret=%d)\n", __func__,
ret);
return ret;
}
plat = dev_get_parent_platdata(dev);
plat->cs = cs;
if (speed) {
plat->max_hz = speed;
} else {
printf("Warning: SPI speed fallback to %u kHz\n",
SPI_DEFAULT_SPEED_HZ / 1000);
plat->max_hz = SPI_DEFAULT_SPEED_HZ;
}
plat->mode = mode;
created = true;
} else if (ret) {
printf("Invalid chip select %d:%d (err=%d)\n", busnum, cs,
ret);
return ret;
}
if (!device_active(dev)) {
struct spi_slave *slave;
ret = device_probe(dev);
if (ret)
goto err;
slave = dev_get_parent_priv(dev);
slave->dev = dev;
}
plat = dev_get_parent_platdata(dev);
/* get speed and mode from platdata when available */
if (plat->max_hz) {
speed = plat->max_hz;
mode = plat->mode;
}
ret = spi_set_speed_mode(bus, speed, mode);
if (ret)
goto err;
*busp = bus;
*devp = dev_get_parent_priv(dev);
debug("%s: bus=%p, slave=%p\n", __func__, bus, *devp);
return 0;
err:
debug("%s: Error path, created=%d, device '%s'\n", __func__,
created, dev->name);
if (created) {
device_remove(dev, DM_REMOVE_NORMAL);
device_unbind(dev);
}
return ret;
}
/* 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, DM_REMOVE_NORMAL);
slave->dev = NULL;
}
int spi_slave_ofdata_to_platdata(struct udevice *dev,
struct dm_spi_slave_platdata *plat)
{
int mode = 0;
int value;
plat->cs = dev_read_u32_default(dev, "reg", -1);
plat->max_hz = dev_read_u32_default(dev, "spi-max-frequency",
SPI_DEFAULT_SPEED_HZ);
if (dev_read_bool(dev, "spi-cpol"))
mode |= SPI_CPOL;
if (dev_read_bool(dev, "spi-cpha"))
mode |= SPI_CPHA;
if (dev_read_bool(dev, "spi-cs-high"))
mode |= SPI_CS_HIGH;
if (dev_read_bool(dev, "spi-3wire"))
mode |= SPI_3WIRE;
if (dev_read_bool(dev, "spi-half-duplex"))
mode |= SPI_PREAMBLE;
/* Device DUAL/QUAD mode */
value = dev_read_u32_default(dev, "spi-tx-bus-width", 1);
switch (value) {
case 1:
break;
case 2:
mode |= SPI_TX_DUAL;
break;
case 4:
mode |= SPI_TX_QUAD;
break;
default:
warn_non_spl("spi-tx-bus-width %d not supported\n", value);
break;
}
value = dev_read_u32_default(dev, "spi-rx-bus-width", 1);
switch (value) {
case 1:
break;
case 2:
mode |= SPI_RX_DUAL;
break;
case 4:
mode |= SPI_RX_QUAD;
break;
default:
warn_non_spl("spi-rx-bus-width %d not supported\n", value);
break;
}
plat->mode = mode;
return 0;
}
UCLASS_DRIVER(spi) = {
.id = UCLASS_SPI,
.name = "spi",
.flags = DM_UC_FLAG_SEQ_ALIAS,
#if !CONFIG_IS_ENABLED(OF_PLATDATA)
.post_bind = dm_scan_fdt_dev,
#endif
.post_probe = spi_post_probe,
.child_pre_probe = spi_child_pre_probe,
.per_device_auto_alloc_size = sizeof(struct dm_spi_bus),
.per_child_auto_alloc_size = sizeof(struct spi_slave),
.per_child_platdata_auto_alloc_size =
sizeof(struct dm_spi_slave_platdata),
#if !CONFIG_IS_ENABLED(OF_PLATDATA)
.child_post_bind = spi_child_post_bind,
#endif
};
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,
};