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path: root/drivers/mfd/syscon.c
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Diffstat (limited to 'drivers/mfd/syscon.c')
-rw-r--r--drivers/mfd/syscon.c96
1 files changed, 74 insertions, 22 deletions
diff --git a/drivers/mfd/syscon.c b/drivers/mfd/syscon.c
index ca15878ce5c0..72373b113885 100644
--- a/drivers/mfd/syscon.c
+++ b/drivers/mfd/syscon.c
@@ -15,6 +15,7 @@
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/list.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
@@ -22,31 +23,94 @@
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
+#include <linux/slab.h>
static struct platform_driver syscon_driver;
+static DEFINE_SPINLOCK(syscon_list_slock);
+static LIST_HEAD(syscon_list);
+
struct syscon {
+ struct device_node *np;
struct regmap *regmap;
+ struct list_head list;
+};
+
+static struct regmap_config syscon_regmap_config = {
+ .reg_bits = 32,
+ .val_bits = 32,
+ .reg_stride = 4,
};
-static int syscon_match_node(struct device *dev, void *data)
+static struct syscon *of_syscon_register(struct device_node *np)
{
- struct device_node *dn = data;
+ struct syscon *syscon;
+ struct regmap *regmap;
+ void __iomem *base;
+ int ret;
+ struct regmap_config syscon_config = syscon_regmap_config;
+
+ if (!of_device_is_compatible(np, "syscon"))
+ return ERR_PTR(-EINVAL);
+
+ syscon = kzalloc(sizeof(*syscon), GFP_KERNEL);
+ if (!syscon)
+ return ERR_PTR(-ENOMEM);
+
+ base = of_iomap(np, 0);
+ if (!base) {
+ ret = -ENOMEM;
+ goto err_map;
+ }
+
+ /* Parse the device's DT node for an endianness specification */
+ if (of_property_read_bool(np, "big-endian"))
+ syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
+ else if (of_property_read_bool(np, "little-endian"))
+ syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
+
+ regmap = regmap_init_mmio(NULL, base, &syscon_config);
+ if (IS_ERR(regmap)) {
+ pr_err("regmap init failed\n");
+ ret = PTR_ERR(regmap);
+ goto err_regmap;
+ }
+
+ syscon->regmap = regmap;
+ syscon->np = np;
+
+ spin_lock(&syscon_list_slock);
+ list_add_tail(&syscon->list, &syscon_list);
+ spin_unlock(&syscon_list_slock);
- return (dev->of_node == dn) ? 1 : 0;
+ return syscon;
+
+err_regmap:
+ iounmap(base);
+err_map:
+ kfree(syscon);
+ return ERR_PTR(ret);
}
struct regmap *syscon_node_to_regmap(struct device_node *np)
{
- struct syscon *syscon;
- struct device *dev;
+ struct syscon *entry, *syscon = NULL;
- dev = driver_find_device(&syscon_driver.driver, NULL, np,
- syscon_match_node);
- if (!dev)
- return ERR_PTR(-EPROBE_DEFER);
+ spin_lock(&syscon_list_slock);
- syscon = dev_get_drvdata(dev);
+ list_for_each_entry(entry, &syscon_list, list)
+ if (entry->np == np) {
+ syscon = entry;
+ break;
+ }
+
+ spin_unlock(&syscon_list_slock);
+
+ if (!syscon)
+ syscon = of_syscon_register(np);
+
+ if (IS_ERR(syscon))
+ return ERR_CAST(syscon);
return syscon->regmap;
}
@@ -110,17 +174,6 @@ struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np,
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle);
-static const struct of_device_id of_syscon_match[] = {
- { .compatible = "syscon", },
- { },
-};
-
-static struct regmap_config syscon_regmap_config = {
- .reg_bits = 32,
- .val_bits = 32,
- .reg_stride = 4,
-};
-
static int syscon_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -167,7 +220,6 @@ static struct platform_driver syscon_driver = {
.driver = {
.name = "syscon",
.owner = THIS_MODULE,
- .of_match_table = of_syscon_match,
},
.probe = syscon_probe,
.id_table = syscon_ids,