mirror of
https://github.com/brain-hackers/u-boot-brain
synced 2024-08-20 00:48:52 +09:00
![Simon Glass](/assets/img/avatar_default.png)
The current name is inconsistent with other driver model data access functions. Rename it and fix up all users. Signed-off-by: Simon Glass <sjg@chromium.org> Reviewed-by: Joe Hershberger <joe.hershberger@ni.com>
196 lines
4.6 KiB
C
196 lines
4.6 KiB
C
/*
|
|
* Chromium OS cros_ec driver - SPI interface
|
|
*
|
|
* Copyright (c) 2012 The Chromium OS Authors.
|
|
*
|
|
* SPDX-License-Identifier: GPL-2.0+
|
|
*/
|
|
|
|
/*
|
|
* The Matrix Keyboard Protocol driver handles talking to the keyboard
|
|
* controller chip. Mostly this is for keyboard functions, but some other
|
|
* things have slipped in, so we provide generic services to talk to the
|
|
* KBC.
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <cros_ec.h>
|
|
#include <dm.h>
|
|
#include <errno.h>
|
|
#include <spi.h>
|
|
|
|
DECLARE_GLOBAL_DATA_PTR;
|
|
|
|
int cros_ec_spi_packet(struct udevice *udev, int out_bytes, int in_bytes)
|
|
{
|
|
struct cros_ec_dev *dev = dev_get_uclass_priv(udev);
|
|
struct spi_slave *slave = dev_get_parent_priv(dev->dev);
|
|
ulong start;
|
|
uint8_t byte;
|
|
int rv;
|
|
|
|
/* Do the transfer */
|
|
if (spi_claim_bus(slave)) {
|
|
debug("%s: Cannot claim SPI bus\n", __func__);
|
|
return -1;
|
|
}
|
|
|
|
rv = spi_xfer(slave, out_bytes * 8, dev->dout, NULL, SPI_XFER_BEGIN);
|
|
if (rv)
|
|
goto done;
|
|
start = get_timer(0);
|
|
while (1) {
|
|
rv = spi_xfer(slave, 8, NULL, &byte, 0);
|
|
if (byte == SPI_PREAMBLE_END_BYTE)
|
|
break;
|
|
if (rv)
|
|
goto done;
|
|
if (get_timer(start) > 100) {
|
|
rv = -ETIMEDOUT;
|
|
goto done;
|
|
}
|
|
}
|
|
|
|
rv = spi_xfer(slave, in_bytes * 8, NULL, dev->din, 0);
|
|
done:
|
|
spi_xfer(slave, 0, NULL, NULL, SPI_XFER_END);
|
|
spi_release_bus(slave);
|
|
|
|
if (rv) {
|
|
debug("%s: Cannot complete SPI transfer\n", __func__);
|
|
return -1;
|
|
}
|
|
|
|
return in_bytes;
|
|
}
|
|
|
|
/**
|
|
* Send a command to a LPC CROS_EC device and return the reply.
|
|
*
|
|
* The device's internal input/output buffers are used.
|
|
*
|
|
* @param dev CROS_EC device
|
|
* @param cmd Command to send (EC_CMD_...)
|
|
* @param cmd_version Version of command to send (EC_VER_...)
|
|
* @param dout Output data (may be NULL If dout_len=0)
|
|
* @param dout_len Size of output data in bytes
|
|
* @param dinp Returns pointer to response data. This will be
|
|
* untouched unless we return a value > 0.
|
|
* @param din_len Maximum size of response in bytes
|
|
* @return number of bytes in response, or -1 on error
|
|
*/
|
|
int cros_ec_spi_command(struct udevice *udev, uint8_t cmd, int cmd_version,
|
|
const uint8_t *dout, int dout_len,
|
|
uint8_t **dinp, int din_len)
|
|
{
|
|
struct cros_ec_dev *dev = dev_get_uclass_priv(udev);
|
|
struct spi_slave *slave = dev_get_parent_priv(dev->dev);
|
|
int in_bytes = din_len + 4; /* status, length, checksum, trailer */
|
|
uint8_t *out;
|
|
uint8_t *p;
|
|
int csum, len;
|
|
int rv;
|
|
|
|
if (dev->protocol_version != 2) {
|
|
debug("%s: Unsupported EC protcol version %d\n",
|
|
__func__, dev->protocol_version);
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Sanity-check input size to make sure it plus transaction overhead
|
|
* fits in the internal device buffer.
|
|
*/
|
|
if (in_bytes > sizeof(dev->din)) {
|
|
debug("%s: Cannot receive %d bytes\n", __func__, din_len);
|
|
return -1;
|
|
}
|
|
|
|
/* We represent message length as a byte */
|
|
if (dout_len > 0xff) {
|
|
debug("%s: Cannot send %d bytes\n", __func__, dout_len);
|
|
return -1;
|
|
}
|
|
|
|
/*
|
|
* Clear input buffer so we don't get false hits for MSG_HEADER
|
|
*/
|
|
memset(dev->din, '\0', in_bytes);
|
|
|
|
if (spi_claim_bus(slave)) {
|
|
debug("%s: Cannot claim SPI bus\n", __func__);
|
|
return -1;
|
|
}
|
|
|
|
out = dev->dout;
|
|
out[0] = EC_CMD_VERSION0 + cmd_version;
|
|
out[1] = cmd;
|
|
out[2] = (uint8_t)dout_len;
|
|
memcpy(out + 3, dout, dout_len);
|
|
csum = cros_ec_calc_checksum(out, 3)
|
|
+ cros_ec_calc_checksum(dout, dout_len);
|
|
out[3 + dout_len] = (uint8_t)csum;
|
|
|
|
/*
|
|
* Send output data and receive input data starting such that the
|
|
* message body will be dword aligned.
|
|
*/
|
|
p = dev->din + sizeof(int64_t) - 2;
|
|
len = dout_len + 4;
|
|
cros_ec_dump_data("out", cmd, out, len);
|
|
rv = spi_xfer(slave, max(len, in_bytes) * 8, out, p,
|
|
SPI_XFER_BEGIN | SPI_XFER_END);
|
|
|
|
spi_release_bus(slave);
|
|
|
|
if (rv) {
|
|
debug("%s: Cannot complete SPI transfer\n", __func__);
|
|
return -1;
|
|
}
|
|
|
|
len = min((int)p[1], din_len);
|
|
cros_ec_dump_data("in", -1, p, len + 3);
|
|
|
|
/* Response code is first byte of message */
|
|
if (p[0] != EC_RES_SUCCESS) {
|
|
printf("%s: Returned status %d\n", __func__, p[0]);
|
|
return -(int)(p[0]);
|
|
}
|
|
|
|
/* Check checksum */
|
|
csum = cros_ec_calc_checksum(p, len + 2);
|
|
if (csum != p[len + 2]) {
|
|
debug("%s: Invalid checksum rx %#02x, calced %#02x\n", __func__,
|
|
p[2 + len], csum);
|
|
return -1;
|
|
}
|
|
|
|
/* Anything else is the response data */
|
|
*dinp = p + 2;
|
|
|
|
return len;
|
|
}
|
|
|
|
static int cros_ec_probe(struct udevice *dev)
|
|
{
|
|
return cros_ec_register(dev);
|
|
}
|
|
|
|
static struct dm_cros_ec_ops cros_ec_ops = {
|
|
.packet = cros_ec_spi_packet,
|
|
.command = cros_ec_spi_command,
|
|
};
|
|
|
|
static const struct udevice_id cros_ec_ids[] = {
|
|
{ .compatible = "google,cros-ec-spi" },
|
|
{ }
|
|
};
|
|
|
|
U_BOOT_DRIVER(cros_ec_spi) = {
|
|
.name = "cros_ec_spi",
|
|
.id = UCLASS_CROS_EC,
|
|
.of_match = cros_ec_ids,
|
|
.probe = cros_ec_probe,
|
|
.ops = &cros_ec_ops,
|
|
};
|