On Fri, Feb 01, 2013 at 12:58:02PM +0100, Lars-Peter Clausen wrote: > 013 10:43 PM, Guenter Roeck wrote: > > Provide bindings, new API access functions, and parse OF data > > during initialization. > > > > Hi Guenter, > > Thanks for taking care of this. > > I'd prefer to have only one iio_get_channel which handles both the dt and the > non-dt case. Otherwise we'll soon have constructs like > > if (dev->of_node) > chan = of_iio_get_channel(dev->of_node, 1); > else > chan = iio_get_channel(dev_name(dev), "vcc"); > > appearing all over the place in drivers code. I'd keep the actual > implementation pretty close to what the clk framework does. E.g. take a look at > of_clk_get_by_name() and clk_get() in clkdev.c. And don't take a detour via the > iio_map lookup for the devicetree case, just loop over all IIO devices and > match by of_node. This should allow us to simplify the code quite a bit. > Yes, I just could not figure out how to loop over the list of iio devices. That is why I hijacked iio_map which does provide a list. Any hints ? Thanks, Guenter > - Lars > > On 01/31/2 > > > 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 > > +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 > > +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. > > + > > +==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) > > +{ > > To be honest I find this whole function a bit confusing. If we are using > devicetree, we shouldn't need to register iio_map. Maybe just skip over > io-channel-output-names for now, until we figure out if we really need this and > what for. > > > + 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 */ > > + 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); > > > [...] > > -- 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
