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 >> + >> +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
