| Message ID | 1467968852-6175-2-git-send-email-linus.walleij@linaro.org |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
On 07/08/2016 02:07 AM, Linus Walleij wrote: > On some systems (such as the Qualcomm APQ8060 Dragonboard) the > RESET signal of the SMSC911x is not pulled up by a resistor but > connected to a GPIO line, so that the operating system must > explicitly deassert RESET before use. > > Support this in the SMSC911x driver so this ethernet connector > can be used on such targets. > > Signed-off-by: Linus Walleij <linus.walleij@linaro.org> > --- > drivers/net/ethernet/smsc/smsc911x.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c > index 8af25563f627..125d58ac22bd 100644 > --- a/drivers/net/ethernet/smsc/smsc911x.c > +++ b/drivers/net/ethernet/smsc/smsc911x.c > @@ -62,6 +62,7 @@ > #include <linux/acpi.h> > #include <linux/pm_runtime.h> > #include <linux/property.h> > +#include <linux/gpio/consumer.h> > > #include "smsc911x.h" > > @@ -149,6 +150,9 @@ struct smsc911x_data { > /* regulators */ > struct regulator_bulk_data supplies[SMSC911X_NUM_SUPPLIES]; > > + /* Reset GPIO */ > + struct gpio_desc *reset_gpiod; > + > /* clock */ > struct clk *clk; > }; > @@ -440,6 +444,15 @@ static int smsc911x_request_resources(struct platform_device *pdev) > netdev_err(ndev, "couldn't get regulators %d\n", > ret); > > + /* Request optional RESET GPIO */ > + pdata->reset_gpiod = devm_gpiod_get(&pdev->dev, "reset", > + GPIOD_OUT_HIGH); > + /* Deassert the signal */ > + if (!IS_ERR(pdata->reset_gpiod)) { This could return -EPROBE_DEFER, which should probably not be ignored. It might be better to use devm_gpiod_get_optional(). If you pass GPIOD_OUT_LOW as parameter to that function, it should take the chip out of reset immediately. See drivers/i2c/muxes/i2c-mux-pca954x.c for an example with a similar use case. Guenter > + dev_info(&pdev->dev, "release reset\n"); > + gpiod_set_value(pdata->reset_gpiod, 0); > + } > + > /* Request clock */ > pdata->clk = clk_get(&pdev->dev, NULL); > if (IS_ERR(pdata->clk)) >
diff --git a/drivers/net/ethernet/smsc/smsc911x.c b/drivers/net/ethernet/smsc/smsc911x.c index 8af25563f627..125d58ac22bd 100644 --- a/drivers/net/ethernet/smsc/smsc911x.c +++ b/drivers/net/ethernet/smsc/smsc911x.c @@ -62,6 +62,7 @@ #include <linux/acpi.h> #include <linux/pm_runtime.h> #include <linux/property.h> +#include <linux/gpio/consumer.h> #include "smsc911x.h" @@ -149,6 +150,9 @@ struct smsc911x_data { /* regulators */ struct regulator_bulk_data supplies[SMSC911X_NUM_SUPPLIES]; + /* Reset GPIO */ + struct gpio_desc *reset_gpiod; + /* clock */ struct clk *clk; }; @@ -440,6 +444,15 @@ static int smsc911x_request_resources(struct platform_device *pdev) netdev_err(ndev, "couldn't get regulators %d\n", ret); + /* Request optional RESET GPIO */ + pdata->reset_gpiod = devm_gpiod_get(&pdev->dev, "reset", + GPIOD_OUT_HIGH); + /* Deassert the signal */ + if (!IS_ERR(pdata->reset_gpiod)) { + dev_info(&pdev->dev, "release reset\n"); + gpiod_set_value(pdata->reset_gpiod, 0); + } + /* Request clock */ pdata->clk = clk_get(&pdev->dev, NULL); if (IS_ERR(pdata->clk))
On some systems (such as the Qualcomm APQ8060 Dragonboard) the RESET signal of the SMSC911x is not pulled up by a resistor but connected to a GPIO line, so that the operating system must explicitly deassert RESET before use. Support this in the SMSC911x driver so this ethernet connector can be used on such targets. Signed-off-by: Linus Walleij <linus.walleij@linaro.org> --- drivers/net/ethernet/smsc/smsc911x.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)