u-boot/drivers/i2c/intel_i2c.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

321 lines
7.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2015 Google, Inc
* Written by Simon Glass <sjg@chromium.org>
*
* SMBus block read/write support added by Stefan Roese:
* Copyright (C) 2016 Stefan Roese <sr@denx.de>
*/
#include <common.h>
#include <dm.h>
#include <i2c.h>
#include <pci.h>
#include <asm/io.h>
/* PCI Configuration Space (D31:F3): SMBus */
#define SMB_BASE 0x20
#define HOSTC 0x40
#define HST_EN (1 << 0)
#define SMB_RCV_SLVA 0x09
/* SMBus I/O bits. */
#define SMBHSTSTAT 0x0
#define SMBHSTCTL 0x2
#define SMBHSTCMD 0x3
#define SMBXMITADD 0x4
#define SMBHSTDAT0 0x5
#define SMBHSTDAT1 0x6
#define SMBBLKDAT 0x7
#define SMBTRNSADD 0x9
#define SMBSLVDATA 0xa
#define SMBAUXCTL 0xd
#define SMLINK_PIN_CTL 0xe
#define SMBUS_PIN_CTL 0xf
/* I801 Hosts Status register bits */
#define SMBHSTSTS_BYTE_DONE 0x80
#define SMBHSTSTS_INUSE_STS 0x40
#define SMBHSTSTS_SMBALERT_STS 0x20
#define SMBHSTSTS_FAILED 0x10
#define SMBHSTSTS_BUS_ERR 0x08
#define SMBHSTSTS_DEV_ERR 0x04
#define SMBHSTSTS_INTR 0x02
#define SMBHSTSTS_HOST_BUSY 0x01
/* I801 Host Control register bits */
#define SMBHSTCNT_INTREN 0x01
#define SMBHSTCNT_KILL 0x02
#define SMBHSTCNT_LAST_BYTE 0x20
#define SMBHSTCNT_START 0x40
#define SMBHSTCNT_PEC_EN 0x80 /* ICH3 and later */
/* Auxiliary control register bits, ICH4+ only */
#define SMBAUXCTL_CRC 1
#define SMBAUXCTL_E32B 2
#define SMBUS_TIMEOUT 100 /* 100 ms */
struct intel_i2c {
u32 base;
int running;
};
static int smbus_wait_until_ready(u32 base)
{
unsigned long ts;
u8 byte;
ts = get_timer(0);
do {
byte = inb(base + SMBHSTSTAT);
if (!(byte & 1))
return 0;
} while (get_timer(ts) < SMBUS_TIMEOUT);
return -ETIMEDOUT;
}
static int smbus_wait_until_done(u32 base)
{
unsigned long ts;
u8 byte;
ts = get_timer(0);
do {
byte = inb(base + SMBHSTSTAT);
if (!((byte & 1) || (byte & ~((1 << 6) | (1 << 0))) == 0))
return 0;
} while (get_timer(ts) < SMBUS_TIMEOUT);
return -ETIMEDOUT;
}
static int smbus_block_read(u32 base, u8 dev, u8 *buffer,
int offset, int len)
{
u8 buf_temp[32];
int count;
int i;
debug("%s (%d): dev=0x%x offs=0x%x len=0x%x\n",
__func__, __LINE__, dev, offset, len);
if (smbus_wait_until_ready(base) < 0)
return -ETIMEDOUT;
/* Setup transaction */
/* Reset the data buffer index */
inb(base + SMBHSTCTL);
/* Set the device I'm talking too */
outb(((dev & 0x7f) << 1) | 1, base + SMBXMITADD);
/* Set the command/address... */
outb(offset & 0xff, base + SMBHSTCMD);
/* Set up for a block read */
outb((inb(base + SMBHSTCTL) & (~(0x7) << 2)) | (0x5 << 2),
(base + SMBHSTCTL));
/* Clear any lingering errors, so the transaction will run */
outb(inb(base + SMBHSTSTAT), base + SMBHSTSTAT);
/* Start the command */
outb((inb(base + SMBHSTCTL) | SMBHSTCNT_START), base + SMBHSTCTL);
/* Poll for transaction completion */
if (smbus_wait_until_done(base) < 0) {
printf("SMBUS read transaction timeout (dev=0x%x)\n", dev);
return -ETIMEDOUT;
}
count = inb(base + SMBHSTDAT0);
debug("%s (%d): count=%d (len=%d)\n", __func__, __LINE__, count, len);
if (count == 0) {
debug("ERROR: len=0 on read\n");
return -EIO;
}
if (count < len) {
debug("ERROR: too few bytes read\n");
return -EIO;
}
if (count > 32) {
debug("ERROR: count=%d too high\n", count);
return -EIO;
}
/* Read all available bytes from buffer */
for (i = 0; i < count; i++)
buf_temp[i] = inb(base + SMBBLKDAT);
memcpy(buffer, buf_temp, len);
/* Return results of transaction */
if (!(inb(base + SMBHSTSTAT) & SMBHSTSTS_INTR))
return -EIO;
return 0;
}
static int smbus_block_write(u32 base, u8 dev, u8 *buffer,
int offset, int len)
{
int i;
debug("%s (%d): dev=0x%x offs=0x%x len=0x%x\n",
__func__, __LINE__, dev, offset, len);
if (smbus_wait_until_ready(base) < 0)
return -ETIMEDOUT;
/* Setup transaction */
/* Set the device I'm talking too */
outb(((dev & 0x7f) << 1) & ~0x01, base + SMBXMITADD);
/* Set the command/address... */
outb(offset, base + SMBHSTCMD);
/* Set up for a block write */
outb((inb(base + SMBHSTCTL) & (~(0x7) << 2)) | (0x5 << 2),
(base + SMBHSTCTL));
/* Clear any lingering errors, so the transaction will run */
outb(inb(base + SMBHSTSTAT), base + SMBHSTSTAT);
/* Write count in DAT0 register */
outb(len, base + SMBHSTDAT0);
/* Write data bytes... */
for (i = 0; i < len; i++)
outb(*buffer++, base + SMBBLKDAT);
/* Start the command */
outb((inb(base + SMBHSTCTL) | SMBHSTCNT_START), base + SMBHSTCTL);
/* Poll for transaction completion */
if (smbus_wait_until_done(base) < 0) {
printf("SMBUS write transaction timeout (dev=0x%x)\n", dev);
return -ETIMEDOUT;
}
/* Return results of transaction */
if (!(inb(base + SMBHSTSTAT) & SMBHSTSTS_INTR))
return -EIO;
return 0;
}
static int intel_i2c_xfer(struct udevice *bus, struct i2c_msg *msg, int nmsgs)
{
struct intel_i2c *i2c = dev_get_priv(bus);
struct i2c_msg *dmsg, *omsg, dummy;
debug("i2c_xfer: %d messages\n", nmsgs);
memset(&dummy, 0, sizeof(struct i2c_msg));
/*
* We expect either two messages (one with an offset and one with the
* actucal data) or one message (just data)
*/
if (nmsgs > 2 || nmsgs == 0) {
debug("%s: Only one or two messages are supported", __func__);
return -EIO;
}
omsg = nmsgs == 1 ? &dummy : msg;
dmsg = nmsgs == 1 ? msg : msg + 1;
if (dmsg->flags & I2C_M_RD)
return smbus_block_read(i2c->base, dmsg->addr, &dmsg->buf[0],
omsg->buf[0], dmsg->len);
else
return smbus_block_write(i2c->base, dmsg->addr, &dmsg->buf[1],
dmsg->buf[0], dmsg->len - 1);
}
static int intel_i2c_probe_chip(struct udevice *bus, uint chip_addr,
uint chip_flags)
{
struct intel_i2c *i2c = dev_get_priv(bus);
u8 buf[4];
return smbus_block_read(i2c->base, chip_addr, buf, 0, 1);
}
static int intel_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
{
return 0;
}
static int intel_i2c_probe(struct udevice *dev)
{
struct intel_i2c *priv = dev_get_priv(dev);
ulong base;
/* Save base address from PCI BAR */
priv->base = (ulong)dm_pci_map_bar(dev, PCI_BASE_ADDRESS_4,
PCI_REGION_IO);
base = priv->base;
/* Set SMBus enable. */
dm_pci_write_config8(dev, HOSTC, HST_EN);
/* Disable interrupts */
outb(inb(base + SMBHSTCTL) & ~SMBHSTCNT_INTREN, base + SMBHSTCTL);
/* Set 32-byte data buffer mode */
outb(inb(base + SMBAUXCTL) | SMBAUXCTL_E32B, base + SMBAUXCTL);
return 0;
}
static int intel_i2c_bind(struct udevice *dev)
{
static int num_cards __attribute__ ((section(".data")));
char name[20];
/* Create a unique device name for PCI type devices */
if (device_is_on_pci_bus(dev)) {
/*
* ToDo:
* Setting req_seq in the driver is probably not recommended.
* But without a DT alias the number is not configured. And
* using this driver is impossible for PCIe I2C devices.
* This can be removed, once a better (correct) way for this
* is found and implemented.
*/
dev->req_seq = num_cards;
sprintf(name, "intel_i2c#%u", num_cards++);
device_set_name(dev, name);
}
return 0;
}
static const struct dm_i2c_ops intel_i2c_ops = {
.xfer = intel_i2c_xfer,
.probe_chip = intel_i2c_probe_chip,
.set_bus_speed = intel_i2c_set_bus_speed,
};
static const struct udevice_id intel_i2c_ids[] = {
{ .compatible = "intel,ich-i2c" },
{ }
};
U_BOOT_DRIVER(intel_i2c) = {
.name = "i2c_intel",
.id = UCLASS_I2C,
.of_match = intel_i2c_ids,
.ops = &intel_i2c_ops,
.priv_auto_alloc_size = sizeof(struct intel_i2c),
.bind = intel_i2c_bind,
.probe = intel_i2c_probe,
};
static struct pci_device_id intel_smbus_pci_supported[] = {
/* Intel BayTrail SMBus on the PCI bus */
{ PCI_VDEVICE(INTEL, 0x0f12) },
/* Intel IvyBridge (Panther Point PCH) SMBus on the PCI bus */
{ PCI_VDEVICE(INTEL, 0x1e22) },
{},
};
U_BOOT_PCI_DEVICE(intel_i2c, intel_smbus_pci_supported);