[PATCH v3 2/5] net: asix: Avoid looping when the device is disconnected

From: robert . foss
Date: Mon Aug 29 2016 - 09:33:02 EST


From: Vincent Palatin <vpalatin@xxxxxxxxxxxx>

Check the answers from the USB stack and avoid re-sending multiple times
the request if the device has disappeared.

Signed-off-by: Vincent Palatin <vpalatin@xxxxxxxxxxxx>
Signed-off-by: Robert Foss <robert.foss@xxxxxxxxxxxxx>
Tested-by: Robert Foss <robert.foss@xxxxxxxxxxxxx>
---
drivers/net/usb/asix_common.c | 56 +++++++++++++++++++++++++++++++++---------
drivers/net/usb/asix_devices.c | 2 ++
2 files changed, 46 insertions(+), 12 deletions(-)

diff --git a/drivers/net/usb/asix_common.c b/drivers/net/usb/asix_common.c
index 25609ee..f79eb12 100644
--- a/drivers/net/usb/asix_common.c
+++ b/drivers/net/usb/asix_common.c
@@ -428,13 +428,21 @@ int asix_mdio_read(struct net_device *netdev, int phy_id, int loc)
__le16 res;
u8 smsr;
int i = 0;
+ int ret;

mutex_lock(&dev->phy_mutex);
do {
- asix_set_sw_mii(dev, 0);
+ ret = asix_set_sw_mii(dev, 0);
+ if (ret == -ENODEV)
+ break;
usleep_range(1000, 1100);
- asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG, 0, 0, 1, &smsr, 0);
- } while (!(smsr & AX_HOST_EN) && (i++ < 30));
+ ret = asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG,
+ 0, 0, 1, &smsr, 0);
+ } while (!(smsr & AX_HOST_EN) && (i++ < 30) && (ret != -ENODEV));
+ if (ret == -ENODEV) {
+ mutex_unlock(&dev->phy_mutex);
+ return ret;
+ }

asix_read_cmd(dev, AX_CMD_READ_MII_REG, phy_id,
(__u16)loc, 2, &res, 0);
@@ -453,16 +461,24 @@ void asix_mdio_write(struct net_device *netdev, int phy_id, int loc, int val)
__le16 res = cpu_to_le16(val);
u8 smsr;
int i = 0;
+ int ret;

netdev_dbg(dev->net, "asix_mdio_write() phy_id=0x%02x, loc=0x%02x, val=0x%04x\n",
phy_id, loc, val);

mutex_lock(&dev->phy_mutex);
do {
- asix_set_sw_mii(dev, 0);
+ ret = asix_set_sw_mii(dev, 0);
+ if (ret == -ENODEV)
+ break;
usleep_range(1000, 1100);
- asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG, 0, 0, 1, &smsr, 0);
- } while (!(smsr & AX_HOST_EN) && (i++ < 30));
+ ret = asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG,
+ 0, 0, 1, &smsr, 0);
+ } while (!(smsr & AX_HOST_EN) && (i++ < 30) && (ret != -ENODEV));
+ if (ret == -ENODEV) {
+ mutex_unlock(&dev->phy_mutex);
+ return;
+ }

asix_write_cmd(dev, AX_CMD_WRITE_MII_REG, phy_id,
(__u16)loc, 2, &res, 0);
@@ -476,13 +492,21 @@ int asix_mdio_read_nopm(struct net_device *netdev, int phy_id, int loc)
__le16 res;
u8 smsr;
int i = 0;
+ int ret;

mutex_lock(&dev->phy_mutex);
do {
- asix_set_sw_mii(dev, 1);
+ ret = asix_set_sw_mii(dev, 1);
+ if (ret == -ENODEV)
+ break;
usleep_range(1000, 1100);
- asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG, 0, 0, 1, &smsr, 1);
- } while (!(smsr & AX_HOST_EN) && (i++ < 30));
+ ret = asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG,
+ 0, 0, 1, &smsr, 1);
+ } while (!(smsr & AX_HOST_EN) && (i++ < 30) && (ret != -ENODEV));
+ if (ret == -ENODEV) {
+ mutex_unlock(&dev->phy_mutex);
+ return ret;
+ }

asix_read_cmd(dev, AX_CMD_READ_MII_REG, phy_id,
(__u16)loc, 2, &res, 1);
@@ -502,16 +526,24 @@ asix_mdio_write_nopm(struct net_device *netdev, int phy_id, int loc, int val)
__le16 res = cpu_to_le16(val);
u8 smsr;
int i = 0;
+ int ret;

netdev_dbg(dev->net, "asix_mdio_write() phy_id=0x%02x, loc=0x%02x, val=0x%04x\n",
phy_id, loc, val);

mutex_lock(&dev->phy_mutex);
do {
- asix_set_sw_mii(dev, 1);
+ ret = asix_set_sw_mii(dev, 1);
+ if (ret == -ENODEV)
+ break;
usleep_range(1000, 1100);
- asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG, 0, 0, 1, &smsr, 1);
- } while (!(smsr & AX_HOST_EN) && (i++ < 30));
+ ret = asix_read_cmd(dev, AX_CMD_STATMNGSTS_REG,
+ 0, 0, 1, &smsr, 1);
+ } while (!(smsr & AX_HOST_EN) && (i++ < 30) && (ret != -ENODEV));
+ if (ret == -ENODEV) {
+ mutex_unlock(&dev->phy_mutex);
+ return;
+ }

asix_write_cmd(dev, AX_CMD_WRITE_MII_REG, phy_id,
(__u16)loc, 2, &res, 1);
diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c
index aaa4290..ebeb730 100644
--- a/drivers/net/usb/asix_devices.c
+++ b/drivers/net/usb/asix_devices.c
@@ -79,6 +79,8 @@ static u32 asix_get_phyid(struct usbnet *dev)
/* Poll for the rare case the FW or phy isn't ready yet. */
for (i = 0; i < 100; i++) {
phy_reg = asix_mdio_read(dev->net, dev->mii.phy_id, MII_PHYSID1);
+ if (phy_reg < 0)
+ return 0;
if (phy_reg != 0 && phy_reg != 0xFFFF)
break;
mdelay(1);
--
2.7.4