When a hw_random device's quality is non-zero, it will automatically be
used to fill the kernel's entropy pool. Since timeriomem_rng is used by
many different devices, the quality needs to be provided by platform
data or device tree.
Signed-off-by: Rick Altherr <raltherr@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
timeriomem_rng only supports a single device instance. This patch
enables multiple timeriomem_rng devices to coexist as well as adds
some additional error checking.
Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
There is no ioremap'ing or anything in timeriomem-rng.c as I foolishly
used already remapped virtual addresses instead of passing the physical
address to be polled.
This patch fixes this flaw and lets developers do the Right Thing(tm).
Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Some hardware platforms, the TS-7800[1] is one for example, can
supply the kernel with an entropy source, albeit a slow one for
TS-7800 users, by just reading a particular IO address. This
source must not be read above a certain rate otherwise the quality
suffers.
The driver is then hooked into by calling
platform_device_(register|add|del) passing a structure similar to:
------
static struct timeriomem_rng_data ts78xx_ts_rng_data = {
.address = (u32 *__iomem) TS_RNG,
.period = 1000000, /* one second */
};
static struct platform_device ts78xx_ts_rng_device = {
.name = "timeriomem_rng",
.id = -1,
.dev = {
.platform_data = &ts78xx_ts_rng_data,
},
.num_resources = 0,
};
------
[1] http://www.embeddedarm.com/products/board-detail.php?product=TS-7800
Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rick Altherr
Alexander Clouter