[PATCH 3/3] net: mdio-gpio: Add support for separate MDI and MDO gpio pins

From: Guenter Roeck
Date: Tue Apr 15 2014 - 22:17:24 EST


This is for a system with fixed assignments of input and output pins
(various variants of Kontron COMe).

Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
---
drivers/net/phy/mdio-gpio.c | 34 +++++++++++++++++++++++++++++++---
include/linux/mdio-gpio.h | 2 ++
2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/drivers/net/phy/mdio-gpio.c b/drivers/net/phy/mdio-gpio.c
index fac211a..9c4defd 100644
--- a/drivers/net/phy/mdio-gpio.c
+++ b/drivers/net/phy/mdio-gpio.c
@@ -32,8 +32,8 @@

struct mdio_gpio_info {
struct mdiobb_ctrl ctrl;
- int mdc, mdio;
- int mdc_active_low, mdio_active_low;
+ int mdc, mdio, mdo;
+ int mdc_active_low, mdio_active_low, mdo_active_low;
};

static void *mdio_gpio_of_get_data(struct platform_device *pdev)
@@ -60,6 +60,12 @@ static void *mdio_gpio_of_get_data(struct platform_device *pdev)
pdata->mdio = ret;
pdata->mdio_active_low = flags & OF_GPIO_ACTIVE_LOW;

+ ret = of_get_gpio_flags(np, 2, &flags);
+ if (ret > 0) {
+ pdata->mdo = ret;
+ pdata->mdo_active_low = flags & OF_GPIO_ACTIVE_LOW;
+ }
+
return pdata;
}

@@ -68,6 +74,16 @@ static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
struct mdio_gpio_info *bitbang =
container_of(ctrl, struct mdio_gpio_info, ctrl);

+ if (bitbang->mdo) {
+ /* Separate output pin. Always set its value to high
+ * when changing direction. If direction is input,
+ * assume the pin serves as pull-up. If direction is
+ * output, the default value is high.
+ */
+ gpio_set_value(bitbang->mdo, 1 ^ bitbang->mdo_active_low);
+ return;
+ }
+
if (dir)
gpio_direction_output(bitbang->mdio,
1 ^ bitbang->mdio_active_low);
@@ -88,7 +104,10 @@ static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
struct mdio_gpio_info *bitbang =
container_of(ctrl, struct mdio_gpio_info, ctrl);

- gpio_set_value(bitbang->mdio, what ^ bitbang->mdio_active_low);
+ if (bitbang->mdo)
+ gpio_set_value(bitbang->mdo, what ^ bitbang->mdo_active_low);
+ else
+ gpio_set_value(bitbang->mdio, what ^ bitbang->mdio_active_low);
}

static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
@@ -125,6 +144,8 @@ static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
bitbang->mdc_active_low = pdata->mdc_active_low;
bitbang->mdio = pdata->mdio;
bitbang->mdio_active_low = pdata->mdio_active_low;
+ bitbang->mdo = pdata->mdo;
+ bitbang->mdo_active_low = pdata->mdo_active_low;

new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
if (!new_bus)
@@ -151,6 +172,13 @@ static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
if (devm_gpio_request(dev, bitbang->mdio, "mdio"))
goto out_free_bus;

+ if (bitbang->mdo) {
+ if (devm_gpio_request(dev, bitbang->mdo, "mdo"))
+ goto out_free_bus;
+ gpio_direction_output(bitbang->mdo, 1);
+ gpio_direction_input(bitbang->mdio);
+ }
+
gpio_direction_output(bitbang->mdc, 0);

dev_set_drvdata(dev, new_bus);
diff --git a/include/linux/mdio-gpio.h b/include/linux/mdio-gpio.h
index 57e57fe..66c30a7 100644
--- a/include/linux/mdio-gpio.h
+++ b/include/linux/mdio-gpio.h
@@ -17,9 +17,11 @@ struct mdio_gpio_platform_data {
/* GPIO numbers for bus pins */
unsigned int mdc;
unsigned int mdio;
+ unsigned int mdo;

bool mdc_active_low;
bool mdio_active_low;
+ bool mdo_active_low;

unsigned int phy_mask;
int irqs[PHY_MAX_ADDR];
--
1.7.9.7

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