[RFC PATCH 2/4] pinctrl: introduce complex pin description
Ludovic Desroches
ludovic.desroches at atmel.com
Thu Apr 2 02:38:14 PDT 2015
Some extra information may be needed to describe a pin, mainly for
controllers support per pin muxing where groups are an abstract concept.
Instead of using its name, use a 32 bit value whose 16 lowest bits are used
for the pin number and the 16 highest ones can be used for extra information.
Signed-off-by: Ludovic Desroches <ludovic.desroches at atmel.com>
---
drivers/pinctrl/pinconf-generic.c | 115 +++++++++++++++++++++++++++-----------
include/linux/pinctrl/pinctrl.h | 5 ++
2 files changed, 86 insertions(+), 34 deletions(-)
diff --git a/drivers/pinctrl/pinconf-generic.c b/drivers/pinctrl/pinconf-generic.c
index e088666..11f9d1b 100644
--- a/drivers/pinctrl/pinconf-generic.c
+++ b/drivers/pinctrl/pinconf-generic.c
@@ -268,28 +268,53 @@ out:
return ret;
}
-int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
+int pinconf_generic_dt_subnode_to_mux_map(struct pinctrl_dev *pctldev,
struct device_node *np, struct pinctrl_map **map,
unsigned *reserved_maps, unsigned *num_maps,
- enum pinctrl_map_type type)
+ const char *function)
{
int ret;
- const char *function;
- struct device *dev = pctldev->dev;
- unsigned long *configs = NULL;
- unsigned num_configs = 0;
- unsigned reserve;
- struct property *prop;
const char *group;
- const char *subnode_target_type = "pins";
+ struct property *prop;
+ struct device *dev = pctldev->dev;
ret = of_property_read_string(np, "function", &function);
- if (ret < 0) {
- /* EINVAL=missing, which is fine since it's optional */
- if (ret != -EINVAL)
- dev_err(dev, "could not parse property function\n");
- function = NULL;
+
+ of_property_for_each_string(np, "groups", prop, group) {
+
+ ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps,
+ num_maps, 1);
+ if (ret < 0)
+ goto exit;
+
+ ret = pinctrl_utils_add_map_mux(pctldev, map, reserved_maps,
+ num_maps, group, function);
+ if (ret < 0)
+ goto exit;
}
+ ret = 0;
+
+exit:
+ return ret;
+}
+
+int pinconf_generic_dt_subnode_to_conf_map(struct pinctrl_dev *pctldev,
+ struct device_node *np, struct pinctrl_map **map,
+ unsigned *reserved_maps, unsigned *num_maps,
+ enum pinctrl_map_type type)
+{
+ const struct pinctrl_desc *pctldesc = pctldev->desc;
+ int ret;
+ unsigned reserve, pin_id;
+ unsigned long *configs = NULL;
+ const char *pin;
+ const char *group;
+ const char *subnode_target_type = "pins";
+ struct property *prop;
+ const __be32 *cur;
+ u32 val;
+ unsigned num_configs = 0;
+ struct device *dev = pctldev->dev;
ret = pinconf_generic_parse_dt_config(np, pctldev, &configs,
&num_configs);
@@ -298,14 +323,7 @@ int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
return ret;
}
- reserve = 0;
- if (function != NULL)
- reserve++;
- if (num_configs)
- reserve++;
-
- ret = of_property_count_strings(np, "pins");
- if (ret < 0) {
+ if (!of_property_read_bool(np, "pins")) {
ret = of_property_count_strings(np, "groups");
if (ret < 0) {
dev_err(dev, "could not parse property pins/groups\n");
@@ -315,26 +333,35 @@ int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
type = PIN_MAP_TYPE_CONFIGS_GROUP;
subnode_target_type = "groups";
} else {
+ if (pctldesc->complex_pin_desc)
+ ret = of_property_count_u32_elems(np, "pins");
+ else
+ ret = of_property_count_strings(np, "pins");
+
+ if (ret < 0) {
+ dev_err(dev, "could not parse property pins\n");
+ goto exit;
+ }
if (type == PIN_MAP_TYPE_INVALID)
type = PIN_MAP_TYPE_CONFIGS_PIN;
}
- reserve *= ret;
+ reserve = ret;
ret = pinctrl_utils_reserve_map(pctldev, map, reserved_maps,
num_maps, reserve);
if (ret < 0)
goto exit;
- of_property_for_each_string(np, subnode_target_type, prop, group) {
- if (function) {
- ret = pinctrl_utils_add_map_mux(pctldev, map,
- reserved_maps, num_maps, group,
- function);
- if (ret < 0)
- goto exit;
+ if (pctldesc->complex_pin_desc) {
+ of_property_for_each_u32(np, subnode_target_type, prop, cur, val) {
+ pin_id = val & PINCTRL_PIN_MASK;
+ pin = pctldesc->pins[pin_id].name;
+ ret = pinctrl_utils_add_map_configs(pctldev, map,
+ reserved_maps, num_maps, pin, configs,
+ num_configs, type);
}
-
- if (num_configs) {
+ } else {
+ of_property_for_each_string(np, subnode_target_type, prop, group) {
ret = pinctrl_utils_add_map_configs(pctldev, map,
reserved_maps, num_maps, group, configs,
num_configs, type);
@@ -342,12 +369,32 @@ int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
goto exit;
}
}
- ret = 0;
-
exit:
kfree(configs);
return ret;
}
+
+int pinconf_generic_dt_subnode_to_map(struct pinctrl_dev *pctldev,
+ struct device_node *np, struct pinctrl_map **map,
+ unsigned *reserved_maps, unsigned *num_maps,
+ enum pinctrl_map_type type)
+{
+ int ret;
+ const char *function;
+ struct device *dev = pctldev->dev;
+
+ ret = of_property_read_string(np, "function", &function);
+ if (ret < 0) {
+ /* EINVAL=missing, which is fine since it's optional */
+ if (ret != -EINVAL)
+ dev_err(dev, "could not parse property function\n");
+ return pinconf_generic_dt_subnode_to_conf_map(pctldev,
+ np, map, reserved_maps, num_maps, type);
+ } else {
+ return pinconf_generic_dt_subnode_to_mux_map(pctldev,
+ np, map, reserved_maps, num_maps, function);
+ }
+}
EXPORT_SYMBOL_GPL(pinconf_generic_dt_subnode_to_map);
int pinconf_generic_dt_node_to_map(struct pinctrl_dev *pctldev,
diff --git a/include/linux/pinctrl/pinctrl.h b/include/linux/pinctrl/pinctrl.h
index c58b3e1..06a070a 100644
--- a/include/linux/pinctrl/pinctrl.h
+++ b/include/linux/pinctrl/pinctrl.h
@@ -45,6 +45,8 @@ struct pinctrl_pin_desc {
#define PINCTRL_PIN(a, b) { .number = a, .name = b }
#define PINCTRL_PIN_ANON(a) { .number = a }
+#define PINCTRL_PIN_MASK 0xffff
+
/**
* struct pinctrl_gpio_range - each pin controller can provide subranges of
* the GPIO number space to be handled by the controller
@@ -112,6 +114,8 @@ struct pinctrl_ops {
* this pin controller
* @npins: number of descriptors in the array, usually just ARRAY_SIZE()
* of the pins field above
+ * @complex_pin_desc: some pin controller needs more information than the pin
+ * name. In this case pins property uses u32 elements instead of strings
* @pctlops: pin control operation vtable, to support global concepts like
* grouping of pins, this is optional.
* @pmxops: pinmux operations vtable, if you support pinmuxing in your driver
@@ -126,6 +130,7 @@ struct pinctrl_desc {
const char *name;
struct pinctrl_pin_desc const *pins;
unsigned int npins;
+ bool complex_pin_desc;
const struct pinctrl_ops *pctlops;
const struct pinmux_ops *pmxops;
const struct pinconf_ops *confops;
--
2.2.0
More information about the linux-arm-kernel
mailing list