diff options
| -rw-r--r-- | drivers/base/Kconfig | 3 | ||||
| -rw-r--r-- | drivers/base/Makefile | 1 | ||||
| -rw-r--r-- | drivers/base/soc.c | 183 | ||||
| -rw-r--r-- | include/linux/sys_soc.h | 37 |
4 files changed, 224 insertions, 0 deletions
diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index 7be9f79018e9..9aa618acfe97 100644 --- a/drivers/base/Kconfig +++ b/drivers/base/Kconfig @@ -176,6 +176,9 @@ config GENERIC_CPU_DEVICES bool default n +config SOC_BUS + bool + source "drivers/base/regmap/Kconfig" config DMA_SHARED_BUFFER diff --git a/drivers/base/Makefile b/drivers/base/Makefile index 610f9997a403..b6d1b9c4200c 100644 --- a/drivers/base/Makefile +++ b/drivers/base/Makefile @@ -19,6 +19,7 @@ obj-$(CONFIG_MODULES) += module.o endif obj-$(CONFIG_SYS_HYPERVISOR) += hypervisor.o obj-$(CONFIG_REGMAP) += regmap/ +obj-$(CONFIG_SOC_BUS) += soc.o ccflags-$(CONFIG_DEBUG_DRIVER) := -DDEBUG diff --git a/drivers/base/soc.c b/drivers/base/soc.c new file mode 100644 index 000000000000..05f150382da8 --- /dev/null +++ b/drivers/base/soc.c @@ -0,0 +1,183 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * + * Author: Lee Jones <lee.jones@linaro.org> for ST-Ericsson. + * License terms: GNU General Public License (GPL), version 2 + */ + +#include <linux/sysfs.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/stat.h> +#include <linux/slab.h> +#include <linux/idr.h> +#include <linux/spinlock.h> +#include <linux/sys_soc.h> +#include <linux/err.h> + +static DEFINE_IDR(soc_ida); +static DEFINE_SPINLOCK(soc_lock); + +static ssize_t soc_info_get(struct device *dev, + struct device_attribute *attr, + char *buf); + +struct soc_device { + struct device dev; + struct soc_device_attribute *attr; + int soc_dev_num; +}; + +static struct bus_type soc_bus_type = { + .name = "soc", +}; + +static DEVICE_ATTR(machine, S_IRUGO, soc_info_get, NULL); +static DEVICE_ATTR(family, S_IRUGO, soc_info_get, NULL); +static DEVICE_ATTR(soc_id, S_IRUGO, soc_info_get, NULL); +static DEVICE_ATTR(revision, S_IRUGO, soc_info_get, NULL); + +struct device *soc_device_to_device(struct soc_device *soc_dev) +{ + return &soc_dev->dev; +} + +static mode_t soc_attribute_mode(struct kobject *kobj, + struct attribute *attr, + int index) +{ + struct device *dev = container_of(kobj, struct device, kobj); + struct soc_device *soc_dev = container_of(dev, struct soc_device, dev); + + if ((attr == &dev_attr_machine.attr) + && (soc_dev->attr->machine != NULL)) + return attr->mode; + if ((attr == &dev_attr_family.attr) + && (soc_dev->attr->family != NULL)) + return attr->mode; + if ((attr == &dev_attr_revision.attr) + && (soc_dev->attr->revision != NULL)) + return attr->mode; + if ((attr == &dev_attr_soc_id.attr) + && (soc_dev->attr->soc_id != NULL)) + return attr->mode; + + /* Unknown or unfilled attribute. */ + return 0; +} + +static ssize_t soc_info_get(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + struct soc_device *soc_dev = container_of(dev, struct soc_device, dev); + + if (attr == &dev_attr_machine) + return sprintf(buf, "%s\n", soc_dev->attr->machine); + if (attr == &dev_attr_family) + return sprintf(buf, "%s\n", soc_dev->attr->family); + if (attr == &dev_attr_revision) + return sprintf(buf, "%s\n", soc_dev->attr->revision); + if (attr == &dev_attr_soc_id) + return sprintf(buf, "%s\n", soc_dev->attr->soc_id); + + return -EINVAL; + +} + +static struct attribute *soc_attr[] = { + &dev_attr_machine.attr, + &dev_attr_family.attr, + &dev_attr_soc_id.attr, + &dev_attr_revision.attr, + NULL, +}; + +static const struct attribute_group soc_attr_group = { + .attrs = soc_attr, + .is_visible = soc_attribute_mode, +}; + +static const struct attribute_group *soc_attr_groups[] = { + &soc_attr_group, + NULL, +}; + +static void soc_release(struct device *dev) +{ + struct soc_device *soc_dev = container_of(dev, struct soc_device, dev); + + kfree(soc_dev); +} + +struct soc_device *soc_device_register(struct soc_device_attribute *soc_dev_attr) +{ + struct soc_device *soc_dev; + int ret; + + soc_dev = kzalloc(sizeof(*soc_dev), GFP_KERNEL); + if (!soc_dev) { + ret = -ENOMEM; + goto out1; + } + + /* Fetch a unique (reclaimable) SOC ID. */ + do { + if (!ida_pre_get(&soc_ida, GFP_KERNEL)) { + ret = -ENOMEM; + goto out2; + } + + spin_lock(&soc_lock); + ret = ida_get_new(&soc_ida, &soc_dev->soc_dev_num); + spin_unlock(&soc_lock); + + } while (ret == -EAGAIN); + + if (ret) + goto out2; + + soc_dev->attr = soc_dev_attr; + soc_dev->dev.bus = &soc_bus_type; + soc_dev->dev.groups = soc_attr_groups; + soc_dev->dev.release = soc_release; + + dev_set_name(&soc_dev->dev, "soc%d", soc_dev->soc_dev_num); + + ret = device_register(&soc_dev->dev); + if (ret) + goto out3; + + return soc_dev; + +out3: + ida_remove(&soc_ida, soc_dev->soc_dev_num); +out2: + kfree(soc_dev); +out1: + return ERR_PTR(ret); +} + +/* Ensure soc_dev->attr is freed prior to calling soc_device_unregister. */ +void soc_device_unregister(struct soc_device *soc_dev) +{ + ida_remove(&soc_ida, soc_dev->soc_dev_num); + + device_unregister(&soc_dev->dev); +} + +static int __init soc_bus_register(void) +{ + spin_lock_init(&soc_lock); + + return bus_register(&soc_bus_type); +} +core_initcall(soc_bus_register); + +static void __exit soc_bus_unregister(void) +{ + ida_destroy(&soc_ida); + + bus_unregister(&soc_bus_type); +} +module_exit(soc_bus_unregister); diff --git a/include/linux/sys_soc.h b/include/linux/sys_soc.h new file mode 100644 index 000000000000..2739ccb69571 --- /dev/null +++ b/include/linux/sys_soc.h @@ -0,0 +1,37 @@ +/* + * Copyright (C) ST-Ericsson SA 2011 + * Author: Lee Jones <lee.jones@linaro.org> for ST-Ericsson. + * License terms: GNU General Public License (GPL), version 2 + */ +#ifndef __SOC_BUS_H +#define __SOC_BUS_H + +#include <linux/device.h> + +struct soc_device_attribute { + const char *machine; + const char *family; + const char *revision; + const char *soc_id; +}; + +/** + * soc_device_register - register SoC as a device + * @soc_plat_dev_attr: Attributes passed from platform to be attributed to a SoC + */ +struct soc_device *soc_device_register( + struct soc_device_attribute *soc_plat_dev_attr); + +/** + * soc_device_unregister - unregister SoC device + * @dev: SoC device to be unregistered + */ +void soc_device_unregister(struct soc_device *soc_dev); + +/** + * soc_device_to_device - helper function to fetch struct device + * @soc: Previously registered SoC device container + */ +struct device *soc_device_to_device(struct soc_device *soc); + +#endif /* __SOC_BUS_H */ |
