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author | Sascha Hauer <s.hauer@pengutronix.de> | 2016-05-16 09:45:56 -0700 |
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committer | Sascha Hauer <s.hauer@pengutronix.de> | 2016-05-18 07:47:46 +0200 |
commit | 914480a542aabd56ba5220afe0e234fd8213411e (patch) | |
tree | ff46c8b566612f54265f8fcedbe2e2d15179ede2 /drivers/aiodev | |
parent | e9add3ae570a381568fb4851a3a43f0b5ca3b089 (diff) | |
download | barebox-914480a542aabd56ba5220afe0e234fd8213411e.tar.gz barebox-914480a542aabd56ba5220afe0e234fd8213411e.tar.xz |
drivers: Introduce AIODEV subsystem
AIODEV/Aiodevice is a analog I/O framework that can be thought of as a
simplified hybrid between 'hwmon' and 'IIO' subsystems of Linux kernel
This commit is very heavily based on 'iodevice' framework proposal
written by Sascha Hauer.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/aiodev')
-rw-r--r-- | drivers/aiodev/Kconfig | 8 | ||||
-rw-r--r-- | drivers/aiodev/Makefile | 2 | ||||
-rw-r--r-- | drivers/aiodev/core.c | 148 |
3 files changed, 158 insertions, 0 deletions
diff --git a/drivers/aiodev/Kconfig b/drivers/aiodev/Kconfig new file mode 100644 index 0000000000..d6d4ac05a0 --- /dev/null +++ b/drivers/aiodev/Kconfig @@ -0,0 +1,8 @@ +# +# Misc strange devices +# +menuconfig AIODEV + bool "Analog I/O drivers" + +if AIODEV +endif diff --git a/drivers/aiodev/Makefile b/drivers/aiodev/Makefile new file mode 100644 index 0000000000..806464ed69 --- /dev/null +++ b/drivers/aiodev/Makefile @@ -0,0 +1,2 @@ + +obj-$(CONFIG_AIODEV) += core.o diff --git a/drivers/aiodev/core.c b/drivers/aiodev/core.c new file mode 100644 index 0000000000..79f935d710 --- /dev/null +++ b/drivers/aiodev/core.c @@ -0,0 +1,148 @@ +/* + * core.c - Code implementing core functionality of AIODEV susbsystem + * + * Copyright (c) 2015 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix + * + * Copyright (c) 2015 Zodiac Inflight Innovation + * Author: Andrey Smirnov <andrew.smirnov@gmail.com> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <common.h> +#include <aiodev.h> +#include <linux/list.h> +#include <malloc.h> + +LIST_HEAD(aiodevices); +EXPORT_SYMBOL(aiodevices); + +struct aiochannel *aiochannel_get_by_name(const char *name) +{ + struct aiodevice *aiodev; + int i; + + list_for_each_entry(aiodev, &aiodevices, list) { + for (i = 0; i < aiodev->num_channels; i++) + if (!strcmp(name, aiodev->channels[i]->name)) + return aiodev->channels[i]; + } + + return ERR_PTR(-ENOENT); +} +EXPORT_SYMBOL(aiochannel_get_by_name); + +struct aiochannel *aiochannel_get(struct device_d *dev, int index) +{ + struct of_phandle_args spec; + struct aiodevice *aiodev; + int ret, chnum = 0; + + if (!dev->device_node) + return ERR_PTR(-EINVAL); + + ret = of_parse_phandle_with_args(dev->device_node, + "io-channels", + "#io-channel-cells", + index, &spec); + if (ret) + return ERR_PTR(ret); + + list_for_each_entry(aiodev, &aiodevices, list) { + if (aiodev->hwdev->device_node == spec.np) + goto found; + } + + return ERR_PTR(-EPROBE_DEFER); + +found: + if (spec.args_count) + chnum = spec.args[0]; + + if (chnum >= aiodev->num_channels) + return ERR_PTR(-EINVAL); + + return aiodev->channels[chnum]; +} +EXPORT_SYMBOL(aiochannel_get); + +int aiochannel_get_value(struct aiochannel *aiochan, int *value) +{ + struct aiodevice *aiodev = aiochan->aiodev; + + return aiodev->read(aiochan, value); +} +EXPORT_SYMBOL(aiochannel_get_value); + +int aiochannel_get_index(struct aiochannel *aiochan) +{ + return aiochan->index; +} +EXPORT_SYMBOL(aiochannel_get_index); + +static int aiochannel_param_get_value(struct param_d *p, void *priv) +{ + struct aiochannel *aiochan = priv; + + return aiochannel_get_value(aiochan, &aiochan->value); +} + +int aiodevice_register(struct aiodevice *aiodev) +{ + int i, ret; + + if (!aiodev->name && aiodev->hwdev && + aiodev->hwdev->device_node) { + aiodev->dev.id = DEVICE_ID_SINGLE; + + aiodev->name = of_alias_get(aiodev->hwdev->device_node); + if (!aiodev->name) + aiodev->name = aiodev->hwdev->device_node->name; + } + + if (!aiodev->name) { + aiodev->name = "aiodev"; + aiodev->dev.id = DEVICE_ID_DYNAMIC; + } + + strcpy(aiodev->dev.name, aiodev->name); + + aiodev->dev.parent = aiodev->hwdev; + + ret = register_device(&aiodev->dev); + if (ret) + return ret; + + for (i = 0; i < aiodev->num_channels; i++) { + struct aiochannel *aiochan = aiodev->channels[i]; + char *name; + + aiochan->index = i; + aiochan->aiodev = aiodev; + + name = xasprintf("in_value%d_%s", i, aiochan->unit); + + dev_add_param_int(&aiodev->dev, name, NULL, + aiochannel_param_get_value, + &aiochan->value, "%d", aiochan); + + aiochan->name = xasprintf("%s.%s", aiodev->name, name); + + free(name); + } + + list_add_tail(&aiodev->list, &aiodevices); + + return 0; +} +EXPORT_SYMBOL(aiodevice_register); |