at86rf230: make reset pin optionally

This patch make the reset pin optionally. Some devices like the atben
from qi-hardware don't have a reset pin externally. The usually way is
to turn power off/on for the atben device to initiate a device reset.

Signed-off-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ieee802154/at86rf230.c b/drivers/net/ieee802154/at86rf230.c
index 37442407d9483235e3171c1321e581e33df68ad9..47677e3f986f2b8ea14217a59846f4b88d5b6d2c 100644 (file)
--- a/drivers/net/ieee802154/at86rf230.c
+++ b/drivers/net/ieee802154/at86rf230.c
@@ -1059,9 +1059,11 @@ static int at86rf230_probe(struct spi_device *spi)
                return -EINVAL;
        }
 
-       rc = gpio_request(pdata->rstn, "rstn");
-       if (rc)
-               return rc;
+       if (gpio_is_valid(pdata->rstn)) {
+               rc = gpio_request(pdata->rstn, "rstn");
+               if (rc)
+                       return rc;
+       }
 
        if (gpio_is_valid(pdata->slp_tr)) {
                rc = gpio_request(pdata->slp_tr, "slp_tr");
@@ -1069,9 +1071,11 @@ static int at86rf230_probe(struct spi_device *spi)
                        goto err_slp_tr;
        }
 
-       rc = gpio_direction_output(pdata->rstn, 1);
-       if (rc)
-               goto err_gpio_dir;
+       if (gpio_is_valid(pdata->rstn)) {
+               rc = gpio_direction_output(pdata->rstn, 1);
+               if (rc)
+                       goto err_gpio_dir;
+       }
 
        if (gpio_is_valid(pdata->slp_tr)) {
                rc = gpio_direction_output(pdata->slp_tr, 0);
@@ -1080,11 +1084,13 @@ static int at86rf230_probe(struct spi_device *spi)
        }
 
        /* Reset */
-       udelay(1);
-       gpio_set_value(pdata->rstn, 0);
-       udelay(1);
-       gpio_set_value(pdata->rstn, 1);
-       usleep_range(120, 240);
+       if (gpio_is_valid(pdata->rstn)) {
+               udelay(1);
+               gpio_set_value(pdata->rstn, 0);
+               udelay(1);
+               gpio_set_value(pdata->rstn, 1);
+               usleep_range(120, 240);
+       }
 
        rc = __at86rf230_detect_device(spi, &man_id, &part, &version);
        if (rc < 0)
@@ -1198,7 +1204,8 @@ err_gpio_dir:
        if (gpio_is_valid(pdata->slp_tr))
                gpio_free(pdata->slp_tr);
 err_slp_tr:
-       gpio_free(pdata->rstn);
+       if (gpio_is_valid(pdata->rstn))
+               gpio_free(pdata->rstn);
        return rc;
 }
 
@@ -1214,7 +1221,8 @@ static int at86rf230_remove(struct spi_device *spi)
 
        if (gpio_is_valid(pdata->slp_tr))
                gpio_free(pdata->slp_tr);
-       gpio_free(pdata->rstn);
+       if (gpio_is_valid(pdata->rstn))
+               gpio_free(pdata->rstn);
 
        mutex_destroy(&lp->bmux);
        ieee802154_free_device(lp->dev);