[RFC][PATCH] net: stmmac: use msleep instead of udelay for gpio reset

[RFC][PATCH] net: stmmac: use msleep instead of udelay for gpio reset

[Michael Trimarchi]

Reset delay values are expressed in microsecond but most of the
time the delay is more then 2ms and up to 100ms. Use udelay
is wrong for large sleep period. This function is not used
in interrupt context according to the documentation.

Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
---
 drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
index b735fa2..009a86a 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
@@ -157,15 +157,15 @@ int stmmac_mdio_reset(struct mii_bus *bus)
 		}
 
 		reset_gpio = data->reset_gpio;
-		active_low = data->active_low;
+		active_low = !!data->active_low;
 
 		if (!gpio_request(reset_gpio, "mdio-reset")) {
-			gpio_direction_output(reset_gpio, active_low ? 1 : 0);
-			udelay(data->delays[0]);
-			gpio_set_value(reset_gpio, active_low ? 0 : 1);
-			udelay(data->delays[1]);
-			gpio_set_value(reset_gpio, active_low ? 1 : 0);
-			udelay(data->delays[2]);
+			gpio_direction_output(reset_gpio, active_low);
+			msleep(max(1U, data->delays[0] / 1000));
+			gpio_set_value(reset_gpio, !active_low);
+			msleep(max(1U, data->delays[1] / 1000));
+			gpio_set_value(reset_gpio, active_low);
+			msleep(max(1U, data->delays[2] / 1000));
 		}
 	}
 #endif
-- 
1.9.1

Re: [RFC][PATCH] net: stmmac: use msleep instead of udelay for gpio reset

[Fabio Estevam]

On Sat, Apr 18, 2015 at 12:02 PM, Michael Trimarchi
<michael@amarulasolutions.com> wrote:

>                 reset_gpio = data->reset_gpio;
> -               active_low = data->active_low;
> +               active_low = !!data->active_low;

This is an unrelated change.

Re: [RFC][PATCH] net: stmmac: use msleep instead of udelay for gpio reset

[Giuseppe CAVALLARO]

On 4/19/2015 6:11 AM, Michael Trimarchi wrote:
> Hi
>
> On Apr 19, 2015 1:37 AM, "Fabio Estevam" <festevam@gmail.com
> <mailto:festevam@gmail.com>> wrote:
>  >
>  > On Sat, Apr 18, 2015 at 12:02 PM, Michael Trimarchi
>  > <michael@amarulasolutions.com <mailto:michael@amarulasolutions.com>>
> wrote:
>  >
>  > >                 reset_gpio = data->reset_gpio;
>  > > -               active_low = data->active_low;
>  > > +               active_low = !!data->active_low;
>  >
>  > This is an unrelated change.
>
> I have already try to minimize the change. Anyway I will repost it if
> necessary

yes send V2 w/ related changes for ms reset time only

thanks

Peppe

> Michael
>