> Provide bindings, new API access functions, and parse OF data > during initialization. nitpicking below > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> > --- > .../devicetree/bindings/iio/iio-bindings.txt | 97 ++++++++ > drivers/iio/inkern.c | 241 ++++++++++++++++---- > include/linux/iio/consumer.h | 8 + > 3 files changed, 299 insertions(+), 47 deletions(-) > create mode 100644 Documentation/devicetree/bindings/iio/iio-bindings.txt > > diff --git a/Documentation/devicetree/bindings/iio/iio-bindings.txt b/Documentation/devicetree/bindings/iio/iio-bindings.txt > new file mode 100644 > index 0000000..0f51c95 > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/iio-bindings.txt > @@ -0,0 +1,97 @@ > +This binding is a work-in-progress, and are based on clock bindings and is based At first I got confused how clock bindings relate to this. > +suggestions from Lars-Peter Clausen [1]. > + > +Sources of IIO channels can be represented by any node in the device > +tree. Those nodes are designated as IIO providers. IIO consumer > +nodes use a phandle and IIO specifier pair to connect IIO provider > +outputs to IIO inputs. Similar to the gpio specifiers, an IIO > +specifier is an array of one more more cells identifying the IIO of one or more cells? > +output on a device. The length of an IIO specifier is defined by the > +value of a #io-channel-cells property in the clock provider node. > + > +[1] http://marc.info/?l=linux-iio&m=135902119507483&w=2 > + > +==IIO providers== > + > +Required properties: > +#io-channel-cells: Number of cells in an IIO specifier; Typically 0 for nodes > + with a single IIO output and 1 for nodes with multiple > + IIO outputs. > + > +Optional properties: > +io-channel-output-names: > + Recommended to be a list of strings of IIO output signal > + names indexed by the first cell in the IIO specifier. > + However, the meaning of io-channel-output-names is domain > + specific to the IIO provider, and is only provided to > + encourage using the same meaning for the majority of IIO > + providers. This format may not work for IIO providers > + using a complex IIO specifier format. In those cases it > + is recommended to omit this property and create a binding > + specific names property. > + > + IIO consumer nodes must never directly reference > + the provider's io-channel-output-names property. > + > +For example: > + > + adc: adc@35 { > + compatible = "maxim,max1139"; > + reg = <0x35>; > + #io-channel-cells = <1>; > + io-channel-output-names = "adc1", "adc2"; > + }; > + > +- this node defines a device with two named IIO outputs, the first named > + "adc1" and the second named "adc2". Consumer nodes always reference > + IIO channels by index. The names should reflect the IIO output signal > + names for the device. maybe start with: This node defines... as below? > + > +==IIO consumers== > + > +Required properties: > +io-channels: List of phandle and IIO specifier pairs, one pair > + for each IIO input to the device. Note: if the > + IIO provider specifies '0' for #clock-cells, then > + only the phandle portion of the pair will appear. > + > +Optional properties: > +io-channel-names: > + List of IIO input name strings sorted in the same > + order as the io-channels property. Consumers drivers > + will use io-channel-names to match IIO input names > + with IIO specifiers. > +io-channel-ranges: > + Empty property indicating that child nodes can inherit named > + IIO channels from this node. Useful for bus nodes to provide > + and IIO channel to their children. > + > +For example: > + > + device { > + io-channels = <&adc 1>, <&ref 0>; > + io-channel-names = "vcc", "vdd"; > + }; > + > +This represents a device with two IIO inputs, named "vcc" and "vdd". > +The vcc channel is connected to output 1 of the &adc device, and the > +vdd channel is connected to output 0 of the &ref device. > + > +==Example== > + > + adc: max1139@35 { > + compatible = "maxim,max1139"; > + reg = <0x35>; > + #io-channel-cells = <1>; > + }; > + > + ... > + > + iio_hwmon { > + compatible = "iio-hwmon"; > + io-channels = <&adc 0>, <&adc 1>, <&adc 2>, > + <&adc 3>, <&adc 4>, <&adc 5>, > + <&adc 6>, <&adc 7>, <&adc 8>, > + <&adc 9>, <&adc 10>, <&adc 11>; > + io-channel-names = "vcc", "vdd", "vref", "1.2V"; > + }; > diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c > index c42aba6..af80a18 100644 > --- a/drivers/iio/inkern.c > +++ b/drivers/iio/inkern.c > @@ -10,6 +10,7 @@ > #include <linux/export.h> > #include <linux/slab.h> > #include <linux/mutex.h> > +#include <linux/of.h> > > #include <linux/iio/iio.h> > #include "iio_core.h" > @@ -26,13 +27,55 @@ struct iio_map_internal { > static LIST_HEAD(iio_map_list); > static DEFINE_MUTEX(iio_map_list_lock); > > +static struct iio_map *iio_map_of_init(struct iio_dev *idev) > +{ > + struct device_node *np = idev->dev.of_node; > + struct iio_map *maps; > + u32 cells, channels = 1; > + int names, i, ret; > + > + ret = of_property_read_u32(np, "#io-channel-cells", &cells); > + if (ret < 0 || cells > 1) > + return ERR_PTR(-EINVAL); > + > + names = of_property_count_strings(np, "io-channel-output-names"); > + if (names < 0) > + names = 0; > + > + if (channels < names) > + channels = names; > + > + maps = devm_kzalloc(&idev->dev, sizeof(*maps) * (channels + 1), > + GFP_KERNEL); > + if (maps == NULL) > + return ERR_PTR(-ENOMEM); > + > + for (i = 0; i < channels; i++) { > + if (i < names) { > + ret = of_property_read_string_index(np, > + "io-channel-output-names", i, > + &maps[i].consumer_channel); > + if (ret < 0) > + return ERR_PTR(ret); > + } > + /* Use dummy for consumer device names */ > + maps[i].consumer_dev_name = "of"; > + } > + return maps; > +} > + > int iio_map_array_register(struct iio_dev *indio_dev, struct iio_map *maps) > { > int i = 0, ret = 0; > struct iio_map_internal *mapi; > > - if (maps == NULL) > - return 0; > + if (maps == NULL) { > + maps = iio_map_of_init(indio_dev); > + if (IS_ERR(maps)) > + return PTR_ERR(maps); > + if (maps == NULL) > + return 0; > + } > > mutex_lock(&iio_map_list_lock); > while (maps[i].consumer_dev_name != NULL) { > @@ -92,30 +135,14 @@ static const struct iio_chan_spec > return chan; > } > > - > -struct iio_channel *iio_channel_get(const char *name, const char *channel_name) > +struct iio_channel *iio_channel_get_common(struct iio_map_internal *c, > + int index) > { > - struct iio_map_internal *c_i = NULL, *c = NULL; > struct iio_channel *channel; > int err; > > - if (name == NULL && channel_name == NULL) > - return ERR_PTR(-ENODEV); > - > - /* first find matching entry the channel map */ > - mutex_lock(&iio_map_list_lock); > - list_for_each_entry(c_i, &iio_map_list, l) { > - if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) || > - (channel_name && > - strcmp(channel_name, c_i->map->consumer_channel) != 0)) > - continue; > - c = c_i; > - iio_device_get(c->indio_dev); > - break; > - } > - mutex_unlock(&iio_map_list_lock); > if (c == NULL) > - return ERR_PTR(-ENODEV); > + return ERR_PTR(-EPROBE_DEFER); > > channel = kzalloc(sizeof(*channel), GFP_KERNEL); > if (channel == NULL) { > @@ -125,7 +152,13 @@ struct iio_channel *iio_channel_get(const char *name, const char *channel_name) > > channel->indio_dev = c->indio_dev; > > - if (c->map->adc_channel_label) { > + if (index >= 0) { > + if (index >= c->indio_dev->num_channels) { > + err = -EINVAL; > + goto error_no_chan; > + } > + channel->channel = &c->indio_dev->channels[index]; > + } else if (c->map->adc_channel_label) { > channel->channel = > iio_chan_spec_from_name(channel->indio_dev, > c->map->adc_channel_label); > @@ -144,6 +177,60 @@ error_no_mem: > iio_device_put(c->indio_dev); > return ERR_PTR(err); > } > + > +struct iio_channel *of_iio_channel_get(struct device_node *np, int index) > +{ > + struct iio_map_internal *c_i, *c = NULL; > + int err, map_index; > + struct of_phandle_args iiospec; > + > + if (index < 0) > + return ERR_PTR(-EINVAL); > + > + err = of_parse_phandle_with_args(np, "io-channels", > + "#io-channel-cells", > + index, &iiospec); > + if (err) > + return ERR_PTR(err); > + > + map_index = iiospec.args_count ? iiospec.args[0] : 0; > + > + mutex_lock(&iio_map_list_lock); > + list_for_each_entry(c_i, &iio_map_list, l) { > + if (iiospec.np == c_i->indio_dev->dev.of_node) { > + c = c_i; > + iio_device_get(c->indio_dev); > + break; > + } > + } > + of_node_put(iiospec.np); > + mutex_unlock(&iio_map_list_lock); > + return iio_channel_get_common(c, index); > +} > +EXPORT_SYMBOL_GPL(of_iio_channel_get); > + > +struct iio_channel *iio_channel_get(const char *name, > + const char *channel_name) > +{ > + struct iio_map_internal *c_i = NULL, *c = NULL; > + > + if (name == NULL && channel_name == NULL) > + return ERR_PTR(-ENODEV); > + > + /* first find matching entry the channel map */ of the channel map? > + mutex_lock(&iio_map_list_lock); > + list_for_each_entry(c_i, &iio_map_list, l) { > + if ((name && strcmp(name, c_i->map->consumer_dev_name) != 0) || > + (channel_name && strcmp(channel_name, > + c_i->map->consumer_channel) != 0)) > + continue; > + c = c_i; > + iio_device_get(c->indio_dev); > + break; > + } > + mutex_unlock(&iio_map_list_lock); > + return iio_channel_get_common(c, -1); > +} > EXPORT_SYMBOL_GPL(iio_channel_get); > > void iio_channel_release(struct iio_channel *channel) > @@ -159,24 +246,43 @@ struct iio_channel *iio_channel_get_all(struct device *dev) > struct iio_channel *chans; > struct iio_map_internal *c = NULL; > int nummaps = 0; > - int mapind = 0; > + int mapind; > int i, ret; > > if (dev == NULL) > return ERR_PTR(-EINVAL); > + > name = dev_name(dev); > > mutex_lock(&iio_map_list_lock); > /* first count the matching maps */ > - list_for_each_entry(c, &iio_map_list, l) > - if (name && strcmp(name, c->map->consumer_dev_name) != 0) > - continue; > - else > - nummaps++; > - > - if (nummaps == 0) { > - ret = -ENODEV; > - goto error_ret; > + if (dev->of_node) { > + nummaps = 0; > + do { > + int ret; > + > + ret = of_parse_phandle_with_args(dev->of_node, > + "io-channels", > + "#io-channel-cells", > + nummaps, NULL); > + if (ret < 0) > + break; > + } while (++nummaps); > + > + if (nummaps == 0) { > + ret = -ENODEV; > + goto error_ret; > + } > + } else { > + list_for_each_entry(c, &iio_map_list, l) > + if (strcmp(name, c->map->consumer_dev_name) != 0) > + continue; > + else > + nummaps++; > + if (nummaps == 0) { > + ret = -EPROBE_DEFER; > + goto error_ret; > + } > } > > /* NULL terminated array to save passing size */ > @@ -187,24 +293,65 @@ struct iio_channel *iio_channel_get_all(struct device *dev) > } > > /* for each map fill in the chans element */ > - list_for_each_entry(c, &iio_map_list, l) { > - if (name && strcmp(name, c->map->consumer_dev_name) != 0) > - continue; > - chans[mapind].indio_dev = c->indio_dev; > - chans[mapind].data = c->map->consumer_data; > - chans[mapind].channel = > - iio_chan_spec_from_name(chans[mapind].indio_dev, > + if (dev->of_node) { > + /* > + * Device-tree based mapping, search for OF matches. > + */ > + for (mapind = 0; mapind < nummaps; mapind++) { > + int channel; > + struct of_phandle_args iiospec; > + > + ret = of_parse_phandle_with_args(dev->of_node, > + "io-channels", > + "#io-channel-cells", > + mapind, &iiospec); > + if (ret) > + goto error_free_chans; > + channel = iiospec.args_count ? iiospec.args[0] : 0; > + ret = -EPROBE_DEFER; > + list_for_each_entry(c, &iio_map_list, l) { > + if (iiospec.np == c->indio_dev->dev.of_node) { > + ret = 0; > + break; > + } > + } > + if (ret) > + goto error_free_chans; > + if (channel >= c->indio_dev->num_channels) { > + ret = -EINVAL; > + goto error_free_chans; > + } > + chans[mapind].indio_dev = c->indio_dev; > + chans[mapind].data = c->map->consumer_data; > + chans[mapind].channel = > + &c->indio_dev->channels[channel]; > + iio_device_get(c->indio_dev); > + } > + } else { > + /* > + * Platform data based mapping, search for consumer > + * device name. > + */ > + mapind = 0; > + list_for_each_entry(c, &iio_map_list, l) { > + if (strcmp(name, c->map->consumer_dev_name) != 0) > + continue; > + chans[mapind].indio_dev = c->indio_dev; > + chans[mapind].data = c->map->consumer_data; > + chans[mapind].channel = > + iio_chan_spec_from_name(c->indio_dev, > c->map->adc_channel_label); > - if (chans[mapind].channel == NULL) { > - ret = -EINVAL; > + if (chans[mapind].channel == NULL) { > + ret = -EINVAL; > + goto error_free_chans; > + } > + iio_device_get(c->indio_dev); > + mapind++; > + } > + if (mapind < nummaps) { > + ret = -EPROBE_DEFER; > goto error_free_chans; > } > - iio_device_get(chans[mapind].indio_dev); > - mapind++; > - } > - if (mapind == 0) { > - ret = -ENODEV; > - goto error_free_chans; > } > mutex_unlock(&iio_map_list_lock); > > diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h > index 6c44167..a347c15 100644 > --- a/include/linux/iio/consumer.h > +++ b/include/linux/iio/consumer.h > @@ -41,6 +41,14 @@ struct iio_channel *iio_channel_get(const char *name, > const char *consumer_channel); > > /** > + * of_iio_channel_get() - get description of all that is needed to access > + * channel from OF node pointer. > + * @np: Consumer's OF node pointer. > + * @index: Index pointing to the io-channels entry in np. > + */ > +struct iio_channel *of_iio_channel_get(struct device_node *np, int index); > + > +/** > * iio_channel_release() - release channels obtained via iio_channel_get > * @chan: The channel to be released. > */ > -- Peter Meerwald +43-664-2444418 (mobile) -- 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
