blob: 69e16a06a0a77d30bbf50095f888109bd15f0699 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2017
* Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
*
* based on the cmd_ioloop driver/command, which is
*
* (C) Copyright 2014
* Dirk Eibach, Guntermann & Drunck GmbH, dirk.eibach@gdsys.cc
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <dm.h>
#include <log.h>
#include <misc.h>
#include <regmap.h>
#include "gdsys_ioep.h"
/**
* struct gdsys_ioep_priv - Private data structure for IOEP devices
* @map: Register map to be used for the device
* @state: Flag to keep the current status of the RX control (enabled/disabled)
*/
struct gdsys_ioep_priv {
struct regmap *map;
bool state;
};
/**
* enum last_spec - Convenience enum for read data sanity check
* @READ_DATA_IS_LAST: The data to be read should be the final data of the
* current packet
* @READ_DATA_IS_NOT_LAST: The data to be read should not be the final data of
* the current packet
*/
enum last_spec {
READ_DATA_IS_LAST,
READ_DATA_IS_NOT_LAST,
};
static int gdsys_ioep_set_receive(struct udevice *dev, bool val)
{
struct gdsys_ioep_priv *priv = dev_get_priv(dev);
u16 state;
priv->state = !priv->state;
if (val)
state = CTRL_PROC_RECEIVE_ENABLE;
else
state = ~CTRL_PROC_RECEIVE_ENABLE;
gdsys_ioep_set(priv->map, tx_control, state);
if (val) {
/* Set device address to dummy 1 */
gdsys_ioep_set(priv->map, device_address, 1);
}
return !priv->state;
}
static int gdsys_ioep_send(struct udevice *dev, int offset,
const void *buf, int size)
{
struct gdsys_ioep_priv *priv = dev_get_priv(dev);
int k;
u16 *p = (u16 *)buf;
for (k = 0; k < size; ++k)
gdsys_ioep_set(priv->map, transmit_data, *(p++));
gdsys_ioep_set(priv->map, tx_control, CTRL_PROC_RECEIVE_ENABLE |
CTRL_FLUSH_TRANSMIT_BUFFER);
return 0;
}
/**
* receive_byte_buffer() - Read data from a IOEP device
* @dev: The IOEP device to read data from
* @len: The length of the data to read
* @buffer: The buffer to read the data into
* @last_spec: Flag to indicate if the data to be read in this call should be
* the final data of the current packet (i.e. it should be empty
* after this read)
*
* Return: 0 if OK, -ve on error
*/
static int receive_byte_buffer(struct udevice *dev, uint len,
u16 *buffer, enum last_spec last_spec)
{
struct gdsys_ioep_priv *priv = dev_get_priv(dev);
int k;
int ret = -EIO;
for (k = 0; k < len; ++k) {
u16 rx_tx_status;
gdsys_ioep_get(priv->map, receive_data, buffer++);
gdsys_ioep_get(priv->map, rx_tx_status, &rx_tx_status);
/*
* Sanity check: If the data read should have been the last,
* but wasn't, something is wrong
*/
if (k == (len - 1) && (last_spec == READ_DATA_IS_NOT_LAST ||
rx_tx_status & STATE_RX_DATA_LAST))
ret = 0;
}
if (ret)
debug("%s: Error while receiving bufer (err = %d)\n",
dev->name, ret);
return ret;
}
static int gdsys_ioep_receive(struct udevice *dev, int offset, void *buf,
int size)
{
int ret;
struct io_generic_packet header;
u16 *p = (u16 *)buf;
const int header_words = sizeof(struct io_generic_packet) / sizeof(u16);
uint len;
/* Read the packet header */
ret = receive_byte_buffer(dev, header_words, p, READ_DATA_IS_NOT_LAST);
if (ret) {
debug("%s: Failed to read header data (err = %d)\n",
dev->name, ret);
return ret;
}
memcpy(&header, p, header_words * sizeof(u16));
p += header_words;
/* Get payload data length */
len = (header.packet_length + 1) / sizeof(u16);
/* Read the packet payload */
ret = receive_byte_buffer(dev, len, p, READ_DATA_IS_LAST);
if (ret) {
debug("%s: Failed to read payload data (err = %d)\n",
dev->name, ret);
return ret;
}
return 0;
}
static int gdsys_ioep_get_and_reset_status(struct udevice *dev, int msgid,
void *tx_msg, int tx_size,
void *rx_msg, int rx_size)
{
struct gdsys_ioep_priv *priv = dev_get_priv(dev);
const u16 mask = STATE_RX_DIST_ERR | STATE_RX_LENGTH_ERR |
STATE_RX_FRAME_CTR_ERR | STATE_RX_FCS_ERR |
STATE_RX_PACKET_DROPPED | STATE_TX_ERR;
u16 *status = rx_msg;
gdsys_ioep_get(priv->map, rx_tx_status, status);
gdsys_ioep_set(priv->map, rx_tx_status, *status);
return (*status & mask) ? 1 : 0;
}
static const struct misc_ops gdsys_ioep_ops = {
.set_enabled = gdsys_ioep_set_receive,
.write = gdsys_ioep_send,
.read = gdsys_ioep_receive,
.call = gdsys_ioep_get_and_reset_status,
};
static int gdsys_ioep_probe(struct udevice *dev)
{
struct gdsys_ioep_priv *priv = dev_get_priv(dev);
int ret;
ret = regmap_init_mem(dev_ofnode(dev), &priv->map);
if (ret) {
debug("%s: Could not initialize regmap (err = %d)",
dev->name, ret);
return ret;
}
priv->state = false;
return 0;
}
static const struct udevice_id gdsys_ioep_ids[] = {
{ .compatible = "gdsys,io-endpoint" },
{ }
};
U_BOOT_DRIVER(gdsys_ioep) = {
.name = "gdsys_ioep",
.id = UCLASS_MISC,
.ops = &gdsys_ioep_ops,
.flags = DM_UC_FLAG_SEQ_ALIAS,
.of_match = gdsys_ioep_ids,
.probe = gdsys_ioep_probe,
.priv_auto_alloc_size = sizeof(struct gdsys_ioep_priv),
};