u-boot/drivers/bootcount/rtc.c
Simon Glass 41575d8e4c dm: treewide: Rename auto_alloc_size members to be shorter
This construct is quite long-winded. In earlier days it made some sense
since auto-allocation was a strange concept. But with driver model now
used pretty universally, we can shorten this to 'auto'. This reduces
verbosity and makes it easier to read.

Coincidentally it also ensures that every declaration is on one line,
thus making dtoc's job easier.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-12-13 08:00:25 -07:00

90 lines
2 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* (C) Copyright 2018 Theobroma Systems Design und Consulting GmbH
*/
#include <common.h>
#include <bootcount.h>
#include <dm.h>
#include <log.h>
#include <rtc.h>
static const u8 bootcount_magic = 0xbc;
struct bootcount_rtc_priv {
struct udevice *rtc;
u32 offset;
};
static int bootcount_rtc_set(struct udevice *dev, const u32 a)
{
struct bootcount_rtc_priv *priv = dev_get_priv(dev);
const u16 val = bootcount_magic << 8 | (a & 0xff);
if (rtc_write16(priv->rtc, priv->offset, val) < 0) {
debug("%s: rtc_write16 failed\n", __func__);
return -EIO;
}
return 0;
}
static int bootcount_rtc_get(struct udevice *dev, u32 *a)
{
struct bootcount_rtc_priv *priv = dev_get_priv(dev);
u16 val;
if (rtc_read16(priv->rtc, priv->offset, &val) < 0) {
debug("%s: rtc_write16 failed\n", __func__);
return -EIO;
}
if (val >> 8 == bootcount_magic) {
*a = val & 0xff;
return 0;
}
debug("%s: bootcount magic does not match on %04x\n", __func__, val);
return -EIO;
}
static int bootcount_rtc_probe(struct udevice *dev)
{
struct ofnode_phandle_args phandle_args;
struct bootcount_rtc_priv *priv = dev_get_priv(dev);
struct udevice *rtc;
if (dev_read_phandle_with_args(dev, "rtc", NULL, 0, 0, &phandle_args)) {
debug("%s: rtc backing device not specified\n", dev->name);
return -ENOENT;
}
if (uclass_get_device_by_ofnode(UCLASS_RTC, phandle_args.node, &rtc)) {
debug("%s: could not get backing device\n", dev->name);
return -ENODEV;
}
priv->rtc = rtc;
priv->offset = dev_read_u32_default(dev, "offset", 0);
return 0;
}
static const struct bootcount_ops bootcount_rtc_ops = {
.get = bootcount_rtc_get,
.set = bootcount_rtc_set,
};
static const struct udevice_id bootcount_rtc_ids[] = {
{ .compatible = "u-boot,bootcount-rtc" },
{ }
};
U_BOOT_DRIVER(bootcount_rtc) = {
.name = "bootcount-rtc",
.id = UCLASS_BOOTCOUNT,
.priv_auto = sizeof(struct bootcount_rtc_priv),
.probe = bootcount_rtc_probe,
.of_match = bootcount_rtc_ids,
.ops = &bootcount_rtc_ops,
};