On 26/04/15 20:36, Daniel Baluta wrote: > On Sun, Apr 26, 2015 at 10:26 PM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote: >> On 20/04/15 15:02, Daniel Baluta wrote: >>> This creates an IIO configfs subystem named "iio", with a default "triggers" >>> group. >>> >>> Triggers group is used for handling software triggers. To create a new software >>> trigger one must create a directory inside the trigger directory. >>> >>> Software trigger name MUST follow the following convention: >>> * <trigger-type>-<trigger-name> >>> Where: >>> * <trigger_type>, specifies the interrupt source (e.g: hrtimer) >>> * <trigger-name>, specifies the IIO device trigger name >>> >>> Failing to follow this convention will result in an directory creation error. >>> >>> E.g, assuming that hrtimer trigger type is registered with IIO software >>> trigger core: >>> >>> $ mkdir /config/iio/triggers/hrtimer-instance1 >>> >>> Signed-off-by: Daniel Baluta <daniel.baluta@xxxxxxxxx> >> Looks good. Couple of little comments inline. >> >> Jonathan >>> --- >>> drivers/iio/Kconfig | 8 +++ >>> drivers/iio/Makefile | 1 + >>> drivers/iio/industrialio-configfs.c | 117 ++++++++++++++++++++++++++++++++++++ >>> 3 files changed, 126 insertions(+) >>> create mode 100644 drivers/iio/industrialio-configfs.c >>> >>> diff --git a/drivers/iio/Kconfig b/drivers/iio/Kconfig >>> index de7f1d9..c310156 100644 >>> --- a/drivers/iio/Kconfig >>> +++ b/drivers/iio/Kconfig >>> @@ -18,6 +18,14 @@ config IIO_BUFFER >>> Provide core support for various buffer based data >>> acquisition methods. >>> >>> +config IIO_CONFIGFS >>> + tristate "Enable IIO configuration via configfs" >>> + select CONFIGFS_FS >>> + help >>> + This allows configuring various IIO bits through configfs >>> + (e.g. software triggers). For more info see >>> + Documentation/iio/iio_configfs.txt. >>> + >>> if IIO_BUFFER >>> >>> config IIO_BUFFER_CB >>> diff --git a/drivers/iio/Makefile b/drivers/iio/Makefile >>> index df87975..31aead3 100644 >>> --- a/drivers/iio/Makefile >>> +++ b/drivers/iio/Makefile >>> @@ -10,6 +10,7 @@ industrialio-$(CONFIG_IIO_SW_TRIGGER) += industrialio-sw-trigger.o >>> industrialio-$(CONFIG_IIO_BUFFER_CB) += buffer_cb.o >>> >>> obj-$(CONFIG_IIO_TRIGGERED_BUFFER) += industrialio-triggered-buffer.o >>> +obj-$(CONFIG_IIO_CONFIGFS) += industrialio-configfs.o >>> obj-$(CONFIG_IIO_KFIFO_BUF) += kfifo_buf.o >>> >>> obj-y += accel/ >>> diff --git a/drivers/iio/industrialio-configfs.c b/drivers/iio/industrialio-configfs.c >>> new file mode 100644 >>> index 0000000..0361434 >>> --- /dev/null >>> +++ b/drivers/iio/industrialio-configfs.c >>> @@ -0,0 +1,117 @@ >>> +/* >>> + * Industrial I/O configfs bits >>> + * >>> + * Copyright (c) 2015 Intel Corporation >>> + * >>> + * This program is free software; you can redistribute it and/or modify it >>> + * under the terms of the GNU General Public License version 2 as published by >>> + * the Free Software Foundation. >>> + */ >>> + >>> +#include <linux/configfs.h> >>> +#include <linux/module.h> >>> +#include <linux/init.h> >>> +#include <linux/kmod.h> >>> +#include <linux/slab.h> >>> + >>> +#include <linux/iio/iio.h> >>> +#include <linux/iio/sw_trigger.h> >>> + >>> +#define MAX_NAME_LEN 32 >> Strikes me as perhaps a little short given we want to allow 'almost' arbitary names for the triggers. > > We are anyhow, limited by the configfs name len here. > > http://lxr.linux.no/linux+v3.19.1/include/linux/configfs.h#L47 > Fair enough. Missed that. > >>> + >>> +static struct config_group *trigger_make_group(struct config_group *group, >>> + const char *name) >>> +{ >>> + char *type_name; >>> + char *trigger_name; >>> + char buf[MAX_NAME_LEN]; >>> + struct iio_sw_trigger *t; >>> + >>> + snprintf(buf, MAX_NAME_LEN, "%s", name); >>> + >>> + /* group name should have the form <trigger-type>-<trigger-name> */ >>> + type_name = buf; >>> + trigger_name = strchr(buf, '-'); >>> + if (!trigger_name) { >>> + pr_err("Unable to locate '-' in %s. Use <type>-<name>.\n", buf); >>> + return ERR_PTR(-EINVAL); >>> + } >>> + >>> + /* replace - with \0, this nicely separates the two strings */ >>> + *trigger_name = '\0'; >> Dirty trick, but I like it. > > Me too, I borrowed it from the usb gadget code. :) > >>> + trigger_name++; >>> + >>> + t = iio_sw_trigger_create(type_name, trigger_name); >>> + if (IS_ERR(t)) >>> + return ERR_CAST(t); >>> + >>> + config_item_set_name(&t->group.cg_item, name); >>> + >>> + return &t->group; >>> +} >>> + >>> +static void trigger_drop_group(struct config_group *group, >>> + struct config_item *item) >>> +{ >>> + struct iio_sw_trigger *t = to_iio_sw_trigger(item); >>> + >>> + if (t) >>> + iio_sw_trigger_destroy(t); >>> + config_item_put(item); >>> +} >>> + >>> +static struct configfs_group_operations triggers_ops = { >>> + .make_group = &trigger_make_group, >>> + .drop_item = &trigger_drop_group, >>> +}; >>> + >>> +static struct config_item_type iio_triggers_group_type = { >>> + .ct_group_ops = &triggers_ops, >>> + .ct_owner = THIS_MODULE, >>> +}; >>> + >>> +static struct config_group iio_triggers_group = { >>> + .cg_item = { >>> + .ci_namebuf = "triggers", >>> + .ci_type = &iio_triggers_group_type, >>> + }, >>> +}; >>> + >>> +static struct config_group *iio_root_default_groups[] = { >>> + &iio_triggers_group, >>> + NULL >>> +}; >>> + >>> +static struct config_item_type iio_root_group_type = { >>> + .ct_owner = THIS_MODULE, >>> +}; >>> + >>> +static struct configfs_subsystem iio_configfs_subsys = { >>> + .su_group = { >>> + .cg_item = { >>> + .ci_namebuf = "iio", >>> + .ci_type = &iio_root_group_type, >>> + }, >>> + .default_groups = iio_root_default_groups, >>> + }, >>> + .su_mutex = __MUTEX_INITIALIZER(iio_configfs_subsys.su_mutex), >>> +}; >>> + >>> +static int __init iio_configfs_init(void) >>> +{ >>> + config_group_init(&iio_triggers_group); >>> + config_group_init(&iio_configfs_subsys.su_group); >>> + >>> + return configfs_register_subsystem(&iio_configfs_subsys); >>> +} >>> +module_init(iio_configfs_init); >>> + >>> +static void __exit iio_configfs_exit(void) >>> +{ >>> + configfs_unregister_subsystem(&iio_configfs_subsys); >>> +} >>> +module_exit(iio_configfs_exit); >>> + >>> +MODULE_AUTHOR("Daniel Baluta <daniel.baluta@xxxxxxxxx>"); >>> +MODULE_DESCRIPTION("Industrial I/O configfs support"); >>> +MODULE_LICENSE("GPL v2"); > > > thanks, > Daniel. > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
