From d3ede2dba3d800912523838a6db35d562e042101 Mon Sep 17 00:00:00 2001
From: Bob Ham <bob.ham@collabora.com>
Date: Fri, 3 Jun 2016 12:13:07 +0100
Subject: hwrng: chaoskey - Add support for Araneus Alea I USB RNG

Adds support for the Araneus Alea I USB hardware Random Number
Generator which is interfaced with in exactly the same way as the
Altus Metrum ChaosKey.  We just add the appropriate device ID and
modify the config help text.

Signed-off-by: Bob Ham <bob.ham@collabora.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/usb/misc/chaoskey.c | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'drivers/usb/misc/chaoskey.c')

diff --git a/drivers/usb/misc/chaoskey.c b/drivers/usb/misc/chaoskey.c
index 76350e4ee807..9aef46b3dfa8 100644
--- a/drivers/usb/misc/chaoskey.c
+++ b/drivers/usb/misc/chaoskey.c
@@ -55,6 +55,9 @@ MODULE_LICENSE("GPL");
 #define CHAOSKEY_VENDOR_ID	0x1d50	/* OpenMoko */
 #define CHAOSKEY_PRODUCT_ID	0x60c6	/* ChaosKey */
 
+#define ALEA_VENDOR_ID		0x12d8	/* Araneus */
+#define ALEA_PRODUCT_ID		0x0001	/* Alea I */
+
 #define CHAOSKEY_BUF_LEN	64	/* max size of USB full speed packet */
 
 #define NAK_TIMEOUT (HZ)		/* stall/wait timeout for device */
@@ -69,6 +72,7 @@ MODULE_LICENSE("GPL");
 
 static const struct usb_device_id chaoskey_table[] = {
 	{ USB_DEVICE(CHAOSKEY_VENDOR_ID, CHAOSKEY_PRODUCT_ID) },
+	{ USB_DEVICE(ALEA_VENDOR_ID, ALEA_PRODUCT_ID) },
 	{ },
 };
 MODULE_DEVICE_TABLE(usb, chaoskey_table);
-- 
cgit 


From e4a886e811cd07dd5c6f389eae4d35870ec2a483 Mon Sep 17 00:00:00 2001
From: Bob Ham <bob.ham@collabora.com>
Date: Fri, 3 Jun 2016 12:13:08 +0100
Subject: hwrng: chaoskey - Fix URB warning due to timeout on Alea

The first read on an Alea takes about 1.8 seconds, more than the
timeout value waiting for the read.  As a consequence, later URB reuse
causes the warning given below.  To avoid this, we increase the wait
time for the first read on the Alea.

[   78.293247] WARNING: CPU: 3 PID: 1892 at drivers/usb/core/urb.c:338 usb_submit_urb+0x2b4/0x580 [usbcore]
[   78.293250] URB ffff8802135be3c0 submitted while active
[   78.293252] Modules linked in: chaoskey(+) rng_core rfcomm binfmt_misc bnep cfg80211 nfsd auth_rpcgss oid_registry nfs_acl nfs lockd grace fscache sunrpc bridge stp llc tun snd_hda_codec_hdmi snd_hda_codec_realtek snd_hda_codec_generic iTCO_wdt iTCO_vendor_support nls_utf8 nls_cp437 vfat fat intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel efi_pstore kvm irqbypass pcspkr btusb btrtl btbcm btintel uvcvideo joydev bluetooth videobuf2_vmalloc videobuf2_memops efivars videobuf2_v4l2 serio_raw i2c_i801 videobuf2_core videodev cdc_mbim media lpc_ich shpchp mfd_core cdc_ncm usbnet mii cdc_wdm cdc_acm evdev snd_hda_intel snd_hda_codec snd_hwdep snd_hda_core i915 snd_pcm snd_timer i2c_algo_bit drm_kms_helper wmi thinkpad_acpi drm nvram mei_me mei snd soundcore rfkill ac battery i2c_core
[   78.293335]  video button tpm_tis tpm fuse parport_pc ppdev lp parport autofs4 ext4 crc16 jbd2 mbcache algif_skcipher af_alg hid_generic usbhid hid dm_crypt dm_mod sg sr_mod cdrom sd_mod crct10dif_pclmul crc32_pclmul crc32c_intel jitterentropy_rng sha256_generic hmac drbg aesni_intel xhci_pci aes_x86_64 ahci glue_helper xhci_hcd ehci_pci lrw libahci gf128mul ablk_helper cryptd libata sdhci_pci psmouse sdhci scsi_mod ehci_hcd mmc_core usbcore usb_common thermal
[   78.293402] CPU: 3 PID: 1892 Comm: hwrng Not tainted 4.7.0-rc1-linux-14+ #16
[   78.293405] Hardware name: LENOVO 232577G/232577G, BIOS G2ET92WW (2.52 ) 02/22/2013
[   78.293408]  0000000000000000 ffffffff812dfa0f ffff8801fa5b3d68 0000000000000000
[   78.293413]  ffffffff81072224 ffff8802135be3c0 ffff8801fa5b3db8 ffff880212e44210
[   78.293418]  0000000000000040 ffff880209fb32c0 ffff880212e44200 ffffffff8107228f
[   78.293422] Call Trace:
[   78.293432]  [<ffffffff812dfa0f>] ? dump_stack+0x5c/0x7d
[   78.293437]  [<ffffffff81072224>] ? __warn+0xc4/0xe0
[   78.293441]  [<ffffffff8107228f>] ? warn_slowpath_fmt+0x4f/0x60
[   78.293451]  [<ffffffff810a46a2>] ? enqueue_task_fair+0xcd2/0x1260
[   78.293463]  [<ffffffffa001ec54>] ? usb_submit_urb+0x2b4/0x580 [usbcore]
[   78.293474]  [<ffffffff8140c2e5>] ? __pm_runtime_resume+0x55/0x70
[   78.293484]  [<ffffffffa0825212>] ? _chaoskey_fill+0x132/0x250 [chaoskey]
[   78.293485] usbcore: registered new interface driver chaoskey
[   78.293493]  [<ffffffff810aed50>] ? wait_woken+0x90/0x90
[   78.293500]  [<ffffffffa06448c0>] ? devm_hwrng_register+0x80/0x80 [rng_core]
[   78.293505]  [<ffffffffa0825907>] ? chaoskey_rng_read+0x127/0x140 [chaoskey]
[   78.293511]  [<ffffffffa06448c0>] ? devm_hwrng_register+0x80/0x80 [rng_core]
[   78.293515]  [<ffffffffa064492e>] ? hwrng_fillfn+0x6e/0x120 [rng_core]
[   78.293520]  [<ffffffff8108fb5f>] ? kthread+0xcf/0xf0
[   78.293529]  [<ffffffff81596d5f>] ? ret_from_fork+0x1f/0x40
[   78.293535]  [<ffffffff8108fa90>] ? kthread_park+0x50/0x50

Signed-off-by: Bob Ham <bob.ham@collabora.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
---
 drivers/usb/misc/chaoskey.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

(limited to 'drivers/usb/misc/chaoskey.c')

diff --git a/drivers/usb/misc/chaoskey.c b/drivers/usb/misc/chaoskey.c
index 9aef46b3dfa8..6ddd08a32777 100644
--- a/drivers/usb/misc/chaoskey.c
+++ b/drivers/usb/misc/chaoskey.c
@@ -60,7 +60,8 @@ MODULE_LICENSE("GPL");
 
 #define CHAOSKEY_BUF_LEN	64	/* max size of USB full speed packet */
 
-#define NAK_TIMEOUT (HZ)		/* stall/wait timeout for device */
+#define NAK_TIMEOUT (HZ)		/* normal stall/wait timeout */
+#define ALEA_FIRST_TIMEOUT (HZ*3)	/* first stall/wait timeout for Alea */
 
 #ifdef CONFIG_USB_DYNAMIC_MINORS
 #define USB_CHAOSKEY_MINOR_BASE 0
@@ -88,6 +89,7 @@ struct chaoskey {
 	int open;			/* open count */
 	bool present;			/* device not disconnected */
 	bool reading;			/* ongoing IO */
+	bool reads_started;		/* track first read for Alea */
 	int size;			/* size of buf */
 	int valid;			/* bytes of buf read */
 	int used;			/* bytes of buf consumed */
@@ -192,6 +194,9 @@ static int chaoskey_probe(struct usb_interface *interface,
 
 	dev->in_ep = in_ep;
 
+	if (udev->descriptor.idVendor != ALEA_VENDOR_ID)
+		dev->reads_started = 1;
+
 	dev->size = size;
 	dev->present = 1;
 
@@ -361,6 +366,7 @@ static int _chaoskey_fill(struct chaoskey *dev)
 {
 	DEFINE_WAIT(wait);
 	int result;
+	bool started;
 
 	usb_dbg(dev->interface, "fill");
 
@@ -393,10 +399,17 @@ static int _chaoskey_fill(struct chaoskey *dev)
 		goto out;
 	}
 
+	/* The first read on the Alea takes a little under 2 seconds.
+	 * Reads after the first read take only a few microseconds
+	 * though.  Presumably the entropy-generating circuit needs
+	 * time to ramp up.  So, we wait longer on the first read.
+	 */
+	started = dev->reads_started;
+	dev->reads_started = true;
 	result = wait_event_interruptible_timeout(
 		dev->wait_q,
 		!dev->reading,
-		NAK_TIMEOUT);
+		(started ? NAK_TIMEOUT : ALEA_FIRST_TIMEOUT) );
 
 	if (result < 0)
 		goto out;
-- 
cgit