diff options
| author |   Sekhar Nori <nsekhar@ti.com> | 2018-05-09 21:15:15 +0530 |
|---|---|---|
| committer |   David S. Miller <davem@davemloft.net> | 2018-05-10 16:18:59 -0400 |
| commit | 54472edff0afa09e35828b2b81b00695a9da1c17 (patch) | |
| tree | db4fdaf085508718242139a458c75d790cbb15c6 /drivers/net/ethernet/ti/davinci_mdio.c | |
| parent | Merge branch 'dsa-mv88e6xxx-cleanup-Global-Control-2-register' (diff) | |
| download | linux-dev-54472edff0afa09e35828b2b81b00695a9da1c17.tar.xz linux-dev-54472edff0afa09e35828b2b81b00695a9da1c17.zip | |
drivers: net: davinci_mdio: prevent spurious timeout
A well timed kernel preemption in the time_after() loop
in wait_for_idle() can result in a spurious timeout
error to be returned.
Fix it by using readl_poll_timeout() which takes care of
this issue.
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/ti/davinci_mdio.c')
| -rw-r--r-- | drivers/net/ethernet/ti/davinci_mdio.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/drivers/net/ethernet/ti/davinci_mdio.c b/drivers/net/ethernet/ti/davinci_mdio.c index 3c33f4504d8e..98a1c97fb95e 100644 --- a/drivers/net/ethernet/ti/davinci_mdio.c +++ b/drivers/net/ethernet/ti/davinci_mdio.c @@ -34,6 +34,7 @@ #include <linux/clk.h> #include <linux/err.h> #include <linux/io.h> +#include <linux/iopoll.h> #include <linux/pm_runtime.h> #include <linux/davinci_emac.h> #include <linux/of.h> @@ -227,14 +228,14 @@ static inline int wait_for_user_access(struct davinci_mdio_data *data) static inline int wait_for_idle(struct davinci_mdio_data *data) { struct davinci_mdio_regs __iomem *regs = data->regs; - unsigned long timeout = jiffies + msecs_to_jiffies(MDIO_TIMEOUT); + u32 val, ret; - while (time_after(timeout, jiffies)) { - if (__raw_readl(®s->control) & CONTROL_IDLE) - return 0; - } - dev_err(data->dev, "timed out waiting for idle\n"); - return -ETIMEDOUT; + ret = readl_poll_timeout(®s->control, val, val & CONTROL_IDLE, + 0, MDIO_TIMEOUT * 1000); + if (ret) + dev_err(data->dev, "timed out waiting for idle\n"); + + return ret; } static int davinci_mdio_read(struct mii_bus *bus, int phy_id, int phy_reg) |