Parse GpioInt/GpioIo ACPI resources and use the pin configuration
information to generate pin controller maps. These maps are associated
with the "default" state, only if this state is defined in the _DSD
of the acpi device.
Signed-off-by: Irina Tirdea <irina.tirdea@xxxxxxxxx>
---
Documentation/acpi/pinctrl-properties.txt | 8 ++
drivers/pinctrl/acpi.c | 229 ++++++++++++++++++++++++++++++
2 files changed, 237 insertions(+)
diff --git a/Documentation/acpi/pinctrl-properties.txt b/Documentation/acpi/pinctrl-properties.txt
index e93aaaf..8243190 100644
--- a/Documentation/acpi/pinctrl-properties.txt
+++ b/Documentation/acpi/pinctrl-properties.txt
@@ -265,6 +265,14 @@ same way as it is done for device tree [5]. The format for the data subnode is:
configname - name of the pin configuration property
configval - value of the pin configuration property
+== GpioInt()/GpioIo() _CRS resources ==
+
+If the device has any GpioInt/GpioIo _CRS ACPI resources, they are parsed so
+that the pin configuration information is used (e.g. PullUp/PullDown/PullNone).
+The pin configuration from GpioInt/GpioIo will be associated with the "default"
+state, only if such a state is defined in the _DSD of the device. If no
+"default" state is defined, the GPIO configuration from _CRS will be ignored.
+
== References ==
[1] Documentation/pinctrl.txt
diff --git a/drivers/pinctrl/acpi.c b/drivers/pinctrl/acpi.c
index bed1d88..7199c3d 100644
--- a/drivers/pinctrl/acpi.c
+++ b/drivers/pinctrl/acpi.c
@@ -140,6 +140,224 @@ static int acpi_remember_or_free_map(struct pinctrl *p, const char *statename,
return pinctrl_register_map(map, num_maps, false);
}
+#ifdef CONFIG_GENERIC_PINCONF
+struct acpi_gpio_lookup {
+ unsigned int index;
+ bool found;
+ unsigned int n;
+ struct pinctrl_map *map;
+ unsigned num_maps;
+ unsigned reserved_maps;
+ struct pinctrl_dev **pctldevs;
+};
+
+/* For now we only handle acpi pin config values */
+#define ACPI_MAX_CFGS 1
+
+static int acpi_parse_gpio_config(const struct acpi_resource_gpio *agpio,
+ unsigned long **configs,
+ unsigned int *nconfigs)
+{
+ enum pin_config_param param;
+ int ret;
+
+ /* Parse configs from GpioInt/GpioIo ACPI resource */
+ *nconfigs = 0;
+ *configs = kcalloc(ACPI_MAX_CFGS, sizeof(*configs), GFP_KERNEL);
+ if (!*configs)
+ return -ENOMEM;
+
+ /* For now, only parse pin_config */
+ switch (agpio->pin_config) {
+ case ACPI_PIN_CONFIG_DEFAULT:
+ param = PIN_CONFIG_BIAS_PULL_PIN_DEFAULT;
+ break;
+ case ACPI_PIN_CONFIG_PULLUP:
+ param = PIN_CONFIG_BIAS_PULL_UP;
+ break;
+ case ACPI_PIN_CONFIG_PULLDOWN:
+ param = PIN_CONFIG_BIAS_PULL_DOWN;
+ break;
+ case ACPI_PIN_CONFIG_NOPULL:
+ param = PIN_CONFIG_BIAS_DISABLE;
+ break;
+ default:
+ ret = -EINVAL;
+ goto exit_free;
+ }
+ *configs[*nconfigs] = pinconf_to_config_packed(param,
+ param == PIN_CONFIG_BIAS_DISABLE ? 0 : 1);
+ (*nconfigs)++;
+
+ return 0;
+
+exit_free:
+ kfree(*configs);
+ return ret;
+}
+
+static int acpi_gpio_to_map(struct acpi_resource *ares, void *data)
+{
+ struct pinctrl_dev *pctldev, **new_pctldevs;
+ struct acpi_gpio_lookup *lookup = data;
+ const struct acpi_resource_gpio *agpio;
+ acpi_handle pctrl_handle = NULL;
+ unsigned int nconfigs, i;
+ unsigned long *configs;
+ acpi_status status;
+ const char *pin;
+ int ret;
+
+ if (ares->type != ACPI_RESOURCE_TYPE_GPIO)
+ return 1;
+ if (lookup->n++ != lookup->index || lookup->found)
+ return 1;
+
+ agpio = &ares->data.gpio;
+
+ /* Get configs from ACPI GPIO resource */
+ ret = acpi_parse_gpio_config(agpio, &configs, &nconfigs);
+ if (ret)
+ return ret;
+
+ /* Get pinctrl reference from GPIO resource */
+ status = acpi_get_handle(NULL, agpio->resource_source.string_ptr,
+ &pctrl_handle);
+ if (ACPI_FAILURE(status) || !pctrl_handle) {
+ ret = -EINVAL;
+ goto exit_free_configs;
+ }
+
+ /* Find the pin controller */
+ pctldev = get_pinctrl_dev_from_acpi(pctrl_handle);
+ if (!pctldev) {
+ ret = -EINVAL;
+ goto exit_free_configs;
+ }
+
+ /* Allocate space for maps and pinctrl_dev references */
+ ret = pinctrl_utils_reserve_map(pctldev, &lookup->map,
+ &lookup->reserved_maps,
+ &lookup->num_maps,
+ agpio->pin_table_length);
+ if (ret < 0)
+ goto exit_free_configs;
+
+ new_pctldevs = krealloc(lookup->pctldevs,
+ sizeof(*new_pctldevs) * lookup->reserved_maps,
+ GFP_KERNEL);
+ if (!new_pctldevs) {
+ ret = -ENOMEM;
+ goto exit_free_configs;
+ }
+ lookup->pctldevs = new_pctldevs;
+
+ /* For each GPIO pin */
+ for (i = 0; i < agpio->pin_table_length; i++) {
+ pin = pin_get_name(pctldev, agpio->pin_table[i]);
+ if (!pin) {
+ ret = -EINVAL;
+ goto exit_free_configs;
+ }
+ lookup->pctldevs[lookup->num_maps] = pctldev;
+ ret = pinctrl_utils_add_map_configs(pctldev, &lookup->map,
+ &lookup->reserved_maps,
+ &lookup->num_maps, pin,
+ configs, nconfigs,
+ PIN_MAP_TYPE_CONFIGS_PIN);
+ if (ret < 0)
+ goto exit_free_configs;
+ }
+
+ lookup->found = true;
+ kfree(configs);
+ return 1;
+
+exit_free_configs:
+ kfree(configs);
+ return ret;
+}
+
+static int acpi_parse_gpio_res(struct pinctrl *p,
+ struct pinctrl_map **map,
+ unsigned *num_maps,
+ struct pinctrl_dev ***pctldevs)
+{
+ struct acpi_gpio_lookup lookup;
+ struct list_head res_list;
+ struct acpi_device *adev;
+ unsigned int index;
+ int ret;
+
+ adev = ACPI_COMPANION(p->dev);
+
+ *map = NULL;
+ *num_maps = 0;
+ memset(&lookup, 0, sizeof(lookup));
+
+ /* Parse all GpioInt/GpioIo resources in _CRS and extract pin conf */
+ for (index = 0; ; index++) {
+ lookup.index = index;
+ lookup.n = 0;
+ lookup.found = false;
+
+ INIT_LIST_HEAD(&res_list);
+ ret = acpi_dev_get_resources(adev, &res_list, acpi_gpio_to_map,
+ &lookup);
+ if (ret < 0)
+ goto exit_free;
+ acpi_dev_free_resource_list(&res_list);
+ if (!lookup.found)
+ break;
+ }
+
+ *map = lookup.map;
+ *num_maps = lookup.num_maps;
+ *pctldevs = lookup.pctldevs;
+
+ return 0;
+
+exit_free:
+ pinctrl_utils_free_map(NULL, lookup.map, lookup.num_maps);
+ kfree(lookup.pctldevs);
+ return ret;
+}
+
+static int acpi_parse_gpio_resources(struct pinctrl *p, char *statename)
+{
+ struct pinctrl_dev **pctldevs;
+ struct pinctrl_map *map;
+ unsigned num_maps;
+ unsigned int i;
+ int ret;
+
+ ret = acpi_parse_gpio_res(p, &map, &num_maps, &pctldevs);
+ if (ret)
+ return ret;
+
+ /* Add maps one by one since pinctrl devices might be different */
+ for (i = 0; i < num_maps; i++) {
+ ret = acpi_remember_or_free_map(p, statename, pctldevs[i],
+ &map[i], 1);
+ if (ret < 0)
+ goto exit_free;
+ }
+
+ kfree(pctldevs);
+ return 0;
+
+exit_free:
+ pinctrl_utils_free_map(NULL, map, num_maps);
+ kfree(pctldevs);
+ return ret;
+}
+#else
+static inline int acpi_parse_gpio_resources(struct pinctrl *p, char *statename)
+{
+ return 0;
+}
+#endif
+
static int acpi_remember_dummy_state(struct pinctrl *p, const char *statename)
{
struct pinctrl_map *map;
@@ -273,6 +491,17 @@ int pinctrl_acpi_to_map(struct pinctrl *p)
}
statename = statenames[state].string.pointer;
+ /*
+ * Parse any GpioInt/GpioIo resources and
+ * associate them with the 'default' state.
+ */
+ if (!strcmp(statename, PINCTRL_STATE_DEFAULT)) {
+ ret = acpi_parse_gpio_resources(p, statename);
+ if (ret)
+ dev_err(p->dev,
+ "Could not parse GPIO resources\n");
+ }
+
/* Retrieve the pinctrl-* property */
propname = kasprintf(GFP_KERNEL, "pinctrl-%d", state);
ret = acpi_dev_get_property(adev, propname, ACPI_TYPE_PACKAGE,
--
1.9.1
--
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