diff options
Diffstat (limited to 'drivers/mfd')
| -rw-r--r-- | drivers/mfd/syscon.c | 96 |
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, |