diff options
Diffstat (limited to 'drivers/crypto/atmel-sha204a.c')
| -rw-r--r-- | drivers/crypto/atmel-sha204a.c | 27 |
1 files changed, 17 insertions, 10 deletions
diff --git a/drivers/crypto/atmel-sha204a.c b/drivers/crypto/atmel-sha204a.c index dbb39ed0cea1..987eadae2007 100644 --- a/drivers/crypto/atmel-sha204a.c +++ b/drivers/crypto/atmel-sha204a.c @@ -19,6 +19,12 @@ #include <linux/workqueue.h> #include "atmel-i2c.h" +/* + * According to review by Bill Cox [1], the ATSHA204 has very low entropy. + * [1] https://www.metzdowd.com/pipermail/cryptography/2014-December/023858.html + */ +static const unsigned short atsha204_quality = 1; + static void atmel_sha204a_rng_done(struct atmel_i2c_work_data *work_data, void *areq, int status) { @@ -158,6 +164,7 @@ static const struct attribute_group atmel_sha204a_groups = { static int atmel_sha204a_probe(struct i2c_client *client) { struct atmel_i2c_client_priv *i2c_priv; + const unsigned short *quality; int ret; ret = atmel_i2c_probe(client); @@ -171,19 +178,19 @@ static int atmel_sha204a_probe(struct i2c_client *client) i2c_priv->hwrng.name = dev_name(&client->dev); i2c_priv->hwrng.read = atmel_sha204a_rng_read; - /* - * According to review by Bill Cox [1], this HWRNG has very low entropy. - * [1] https://www.metzdowd.com/pipermail/cryptography/2014-December/023858.html - */ - i2c_priv->hwrng.quality = 1; + quality = i2c_get_match_data(client); + if (quality) + i2c_priv->hwrng.quality = *quality; ret = devm_hwrng_register(&client->dev, &i2c_priv->hwrng); - if (ret) - dev_warn(&client->dev, "failed to register RNG (%d)\n", ret); + if (ret) { + dev_err(&client->dev, "failed to register RNG (%d)\n", ret); + return ret; + } ret = sysfs_create_group(&client->dev.kobj, &atmel_sha204a_groups); if (ret) { - dev_err(&client->dev, "failed to register sysfs entry\n"); + dev_err(&client->dev, "failed to create sysfs group (%d)\n", ret); return ret; } @@ -203,14 +210,14 @@ static void atmel_sha204a_remove(struct i2c_client *client) } static const struct of_device_id atmel_sha204a_dt_ids[] __maybe_unused = { - { .compatible = "atmel,atsha204", }, + { .compatible = "atmel,atsha204", .data = &atsha204_quality }, { .compatible = "atmel,atsha204a", }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, atmel_sha204a_dt_ids); static const struct i2c_device_id atmel_sha204a_id[] = { - { "atsha204" }, + { "atsha204", (kernel_ulong_t)&atsha204_quality }, { "atsha204a" }, { /* sentinel */ } }; |