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authorSebastian Reichel <sebastian.reichel@collabora.co.uk>2017-05-05 11:06:50 +0200
committerSasha Levin <alexander.levin@verizon.com>2017-06-08 06:12:47 -0400
commit0210333e202b6530d52f5208aebe2d499670a385 (patch)
tree3fac6734d68a21cbc0a3ca7a8e7a95fb30104094
parent8852d28b3f06d30f6bc177df627f0fe50b703a49 (diff)
i2c: i2c-tiny-usb: fix buffer not being DMA capable
[ Upstream commit 5165da5923d6c7df6f2927b0113b2e4d9288661e ] Since v4.9 i2c-tiny-usb generates the below call trace and longer works, since it can't communicate with the USB device. The reason is, that since v4.9 the USB stack checks, that the buffer it should transfer is DMA capable. This was a requirement since v2.2 days, but it usually worked nevertheless. [ 17.504959] ------------[ cut here ]------------ [ 17.505488] WARNING: CPU: 0 PID: 93 at drivers/usb/core/hcd.c:1587 usb_hcd_map_urb_for_dma+0x37c/0x570 [ 17.506545] transfer buffer not dma capable [ 17.507022] Modules linked in: [ 17.507370] CPU: 0 PID: 93 Comm: i2cdetect Not tainted 4.11.0-rc8+ #10 [ 17.508103] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 17.509039] Call Trace: [ 17.509320] ? dump_stack+0x5c/0x78 [ 17.509714] ? __warn+0xbe/0xe0 [ 17.510073] ? warn_slowpath_fmt+0x5a/0x80 [ 17.510532] ? nommu_map_sg+0xb0/0xb0 [ 17.510949] ? usb_hcd_map_urb_for_dma+0x37c/0x570 [ 17.511482] ? usb_hcd_submit_urb+0x336/0xab0 [ 17.511976] ? wait_for_completion_timeout+0x12f/0x1a0 [ 17.512549] ? wait_for_completion_timeout+0x65/0x1a0 [ 17.513125] ? usb_start_wait_urb+0x65/0x160 [ 17.513604] ? usb_control_msg+0xdc/0x130 [ 17.514061] ? usb_xfer+0xa4/0x2a0 [ 17.514445] ? __i2c_transfer+0x108/0x3c0 [ 17.514899] ? i2c_transfer+0x57/0xb0 [ 17.515310] ? i2c_smbus_xfer_emulated+0x12f/0x590 [ 17.515851] ? _raw_spin_unlock_irqrestore+0x11/0x20 [ 17.516408] ? i2c_smbus_xfer+0x125/0x330 [ 17.516876] ? i2c_smbus_xfer+0x125/0x330 [ 17.517329] ? i2cdev_ioctl_smbus+0x1c1/0x2b0 [ 17.517824] ? i2cdev_ioctl+0x75/0x1c0 [ 17.518248] ? do_vfs_ioctl+0x9f/0x600 [ 17.518671] ? vfs_write+0x144/0x190 [ 17.519078] ? SyS_ioctl+0x74/0x80 [ 17.519463] ? entry_SYSCALL_64_fastpath+0x1e/0xad [ 17.519959] ---[ end trace d047c04982f5ac50 ]--- Cc: <stable@vger.kernel.org> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Till Harbaum <till@harbaum.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de> Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
-rw-r--r--drivers/i2c/busses/i2c-tiny-usb.c25
1 files changed, 21 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c
index 0ed77eeff31e..a2e3dd715380 100644
--- a/drivers/i2c/busses/i2c-tiny-usb.c
+++ b/drivers/i2c/busses/i2c-tiny-usb.c
@@ -178,22 +178,39 @@ static int usb_read(struct i2c_adapter *adapter, int cmd,
int value, int index, void *data, int len)
{
struct i2c_tiny_usb *dev = (struct i2c_tiny_usb *)adapter->algo_data;
+ void *dmadata = kmalloc(len, GFP_KERNEL);
+ int ret;
+
+ if (!dmadata)
+ return -ENOMEM;
/* do control transfer */
- return usb_control_msg(dev->usb_dev, usb_rcvctrlpipe(dev->usb_dev, 0),
+ ret = usb_control_msg(dev->usb_dev, usb_rcvctrlpipe(dev->usb_dev, 0),
cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE |
- USB_DIR_IN, value, index, data, len, 2000);
+ USB_DIR_IN, value, index, dmadata, len, 2000);
+
+ memcpy(data, dmadata, len);
+ kfree(dmadata);
+ return ret;
}
static int usb_write(struct i2c_adapter *adapter, int cmd,
int value, int index, void *data, int len)
{
struct i2c_tiny_usb *dev = (struct i2c_tiny_usb *)adapter->algo_data;
+ void *dmadata = kmemdup(data, len, GFP_KERNEL);
+ int ret;
+
+ if (!dmadata)
+ return -ENOMEM;
/* do control transfer */
- return usb_control_msg(dev->usb_dev, usb_sndctrlpipe(dev->usb_dev, 0),
+ ret = usb_control_msg(dev->usb_dev, usb_sndctrlpipe(dev->usb_dev, 0),
cmd, USB_TYPE_VENDOR | USB_RECIP_INTERFACE,
- value, index, data, len, 2000);
+ value, index, dmadata, len, 2000);
+
+ kfree(dmadata);
+ return ret;
}
static void i2c_tiny_usb_free(struct i2c_tiny_usb *dev)