pinctrl: sunxi: Deal with configless pins

Even though the our binding had the assumption that the allwinner,pull and
allwinner,drive properties were optional, the code never took that into
account.

Fix that.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Acked-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/sunxi/pinctrl-sunxi.c b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
index 7e27204..ebe2c73 100644 (file)
--- a/drivers/pinctrl/sunxi/pinctrl-sunxi.c
+++ b/drivers/pinctrl/sunxi/pinctrl-sunxi.c
@@ -261,20 +261,29 @@ static unsigned long *sunxi_pctrl_build_pin_config(struct device_node *node,
 {
        unsigned long *pinconfig;
        unsigned int configlen = 0, idx = 0;
+       int ret;
 
        if (sunxi_pctrl_has_drive_prop(node))
                configlen++;
        if (sunxi_pctrl_has_bias_prop(node))
                configlen++;
 
+       /*
+        * If we don't have any configuration, bail out
+        */
+       if (!configlen)
+               return NULL;
+
        pinconfig = kzalloc(configlen * sizeof(*pinconfig), GFP_KERNEL);
        if (!pinconfig)
-               return NULL;
+               return ERR_PTR(-ENOMEM);
 
        if (sunxi_pctrl_has_drive_prop(node)) {
                int drive = sunxi_pctrl_parse_drive_prop(node);
-               if (drive < 0)
+               if (drive < 0) {
+                       ret = drive;
                        goto err_free;
+               }
 
                pinconfig[idx++] = pinconf_to_config_packed(PIN_CONFIG_DRIVE_STRENGTH,
                                                          drive);
@@ -282,8 +291,10 @@ static unsigned long *sunxi_pctrl_build_pin_config(struct device_node *node,
 
        if (sunxi_pctrl_has_bias_prop(node)) {
                int pull = sunxi_pctrl_parse_bias_prop(node);
-               if (pull < 0)
+               if (pull < 0) {
+                       ret = pull;
                        goto err_free;
+               }
 
                pinconfig[idx++] = pinconf_to_config_packed(pull, 0);
        }
@@ -294,7 +305,7 @@ static unsigned long *sunxi_pctrl_build_pin_config(struct device_node *node,
 
 err_free:
        kfree(pinconfig);
-       return NULL;
+       return ERR_PTR(ret);
 }
 
 static int sunxi_pctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
@@ -328,7 +339,10 @@ static int sunxi_pctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
 
        /*
         * We have two maps for each pin: one for the function, one
-        * for the configuration (bias, strength, etc)
+        * for the configuration (bias, strength, etc).
+        *
+        * We might be slightly overshooting, since we might not have
+        * any configuration.
         */
        nmaps = npins * 2;
        *map = kmalloc(nmaps * sizeof(struct pinctrl_map), GFP_KERNEL);
@@ -336,8 +350,8 @@ static int sunxi_pctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
                return -ENOMEM;
 
        pinconfig = sunxi_pctrl_build_pin_config(node, &configlen);
-       if (!pinconfig) {
-               ret = -EINVAL;
+       if (IS_ERR(pinconfig)) {
+               ret = PTR_ERR(pinconfig);
                goto err_free_map;
        }
 
@@ -364,15 +378,24 @@ static int sunxi_pctrl_dt_node_to_map(struct pinctrl_dev *pctldev,
 
                i++;
 
-               (*map)[i].type = PIN_MAP_TYPE_CONFIGS_GROUP;
-               (*map)[i].data.configs.group_or_pin = group;
-               (*map)[i].data.configs.configs = pinconfig;
-               (*map)[i].data.configs.num_configs = configlen;
-
-               i++;
+               if (pinconfig) {
+                       (*map)[i].type = PIN_MAP_TYPE_CONFIGS_GROUP;
+                       (*map)[i].data.configs.group_or_pin = group;
+                       (*map)[i].data.configs.configs = pinconfig;
+                       (*map)[i].data.configs.num_configs = configlen;
+                       i++;
+               }
        }
 
-       *num_maps = nmaps;
+       *num_maps = i;
+
+       /*
+        * We know have the number of maps we need, we can resize our
+        * map array
+        */
+       *map = krealloc(*map, i * sizeof(struct pinctrl_map), GFP_KERNEL);
+       if (!map)
+               return -ENOMEM;
 
        return 0;