On Wed, Feb 20, 2013 at 06:51:08PM +0000, Jonathan Cameron wrote: > > > Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > >On Wed, Feb 20, 2013 at 11:38:22AM -0600, Rob Herring wrote: > >> On 02/07/2013 11:09 AM, Guenter Roeck wrote: > >> > Provide bindings and parse OF data during initialization. > >> > > >> > Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> > >> > --- > >> > v5: > >> > - Updated examples in bindings. > >> > v4: > >> > - Fixed wrong parameter to dummy of_iio_channel_get_by_name if > >CONFIG_OF is > >> > undefined, and wrong return value. > >> > - Initialize indio_dev->of_node in iio_device_register if the > >calling driver > >> > neglected to do it. > >> > v3: > >> > - Cleaned up documentation (formatting, left-over clock references) > >> > - Updated bindings description to permit sub-devices > >> > - When searching for iio devices, use the pointer to the iio device > >type instead > >> > of strcmp. Rename iio_dev_type to iio_device_type (to match other > >device > >> > types) and make it global for that purpose. Check the OF node > >first, then the > >> > device type, as the node is less likely to match. > >> > - Move the common code in of_iio_channel_get and > >of_iio_channel_get_all to > >> > __of_iio_channel_get. > >> > - Return NULL from of_iio_channel_get_by_name if nothing is found, > >or > >> > an error if there is a problem with consistency or if the > >provider device is > >> > not yet available. > >> > - In iio_channel_get, return if of_iio_channel_get_by_name() > >returns a channel > >> > or an error, and continue otherwise. > >> > v2: > >> > - Rebased to iio/togreg > >> > - Documentation update per feedback > >> > - Dropped io-channel-output-names from the bindings document. The > >property is > >> > not used in the code, and it is not entirely clear what it would > >be used for. > >> > If there is a need for it, we can add it back in later on. > >> > - Don't export OF specific API calls > >> > - For OF support, no longer depend on iio_map > >> > - Add #ifdef CONFIG_OF where appropriate, and ensure that the code > >still builds > >> > if it is not selected. > >> > - Change iio_channel_get to take device pointer as argument instead > >of device > >> > name. Retain old API as of_iio_channel_get_sys. > >> > - iio_channel_get now works for both OF and non-OF configurations > >> > - Use regulator to get vref for max1363 driver. > >> > > >> > .../devicetree/bindings/iio/iio-bindings.txt | 97 > >+++++++++++ > >> > drivers/iio/iio_core.h | 1 + > >> > drivers/iio/industrialio-core.c | 8 +- > >> > drivers/iio/inkern.c | 171 > >++++++++++++++++++++ > >> > 4 files changed, 275 insertions(+), 2 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..1182845 > >> > --- /dev/null > >> > +++ b/Documentation/devicetree/bindings/iio/iio-bindings.txt > >> > @@ -0,0 +1,97 @@ > >> > +This binding is a work-in-progress. It is derived from clock > >bindings, > >> > +and based on suggestions from Lars-Peter Clausen [1]. > >> > >> Bindings are an ABI. It should not be a WIP. What part is a WIP? > >> > >The text is copied from clock bindings. I do not claim to be better > >than the clock subsystem is doing in respect to its bindings. > > > >I'll be more than happy to take this text out if it is a source of > >contention, > >even more so if that is what is holding up the patch. Jonathan ? > I don't really care about the wording though can see why Rob asked! > We will probably have other stuff to add anyway. > Quite likely - for example, I did not add io-output-names since I did not know what to do with it. What do you want me to do ? Submit another version with the sentence deleted, or keep it as-is ? Thanks, Guenter > Jonathan > > > >Thanks, > >Guenter > > > >> Knowing nothing about IIO, the binding seems sane. > >> > >> Rob > >> > >> > +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 or 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 IIO 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. > >> > + > >> > +Example for a simple configuration with no trigger: > >> > + > >> > + adc: voltage-sensor@35 { > >> > + compatible = "maxim,max1139"; > >> > + reg = <0x35>; > >> > + #io-channel-cells = <1>; > >> > + }; > >> > + > >> > +Example for a configuration with trigger: > >> > + > >> > + adc@35 { > >> > + compatible = "some-vendor,some-adc"; > >> > + reg = <0x35>; > >> > + > >> > + adc1: iio-device@0 { > >> > + #io-channel-cells = <1>; > >> > + /* other properties */ > >> > + }; > >> > + adc2: iio-device@1 { > >> > + #io-channel-cells = <1>; > >> > + /* other properties */ > >> > + }; > >> > + }; > >> > + > >> > +==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 #io-channel-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>; > >> > + }; > >> > + > >> > + some_consumer { > >> > + compatible = "some-consumer"; > >> > + io-channels = <&adc 10>, <&adc 11>; > >> > + io-channel-names = "adc1", "adc2"; > >> > + }; > >> > diff --git a/drivers/iio/iio_core.h b/drivers/iio/iio_core.h > >> > index f652e6a..05c1b74 100644 > >> > --- a/drivers/iio/iio_core.h > >> > +++ b/drivers/iio/iio_core.h > >> > @@ -18,6 +18,7 @@ > >> > struct iio_chan_spec; > >> > struct iio_dev; > >> > > >> > +extern struct device_type iio_device_type; > >> > > >> > int __iio_add_chan_devattr(const char *postfix, > >> > struct iio_chan_spec const *chan, > >> > diff --git a/drivers/iio/industrialio-core.c > >b/drivers/iio/industrialio-core.c > >> > index 8848f16..6d8b027 100644 > >> > --- a/drivers/iio/industrialio-core.c > >> > +++ b/drivers/iio/industrialio-core.c > >> > @@ -847,7 +847,7 @@ static void iio_dev_release(struct device > >*device) > >> > kfree(indio_dev); > >> > } > >> > > >> > -static struct device_type iio_dev_type = { > >> > +struct device_type iio_device_type = { > >> > .name = "iio_device", > >> > .release = iio_dev_release, > >> > }; > >> > @@ -869,7 +869,7 @@ struct iio_dev *iio_device_alloc(int > >sizeof_priv) > >> > > >> > if (dev) { > >> > dev->dev.groups = dev->groups; > >> > - dev->dev.type = &iio_dev_type; > >> > + dev->dev.type = &iio_device_type; > >> > dev->dev.bus = &iio_bus_type; > >> > device_initialize(&dev->dev); > >> > dev_set_drvdata(&dev->dev, (void *)dev); > >> > @@ -960,6 +960,10 @@ int iio_device_register(struct iio_dev > >*indio_dev) > >> > { > >> > int ret; > >> > > >> > + /* If the calling driver did not initialize of_node, do it here > >*/ > >> > + if (!indio_dev->dev.of_node && indio_dev->dev.parent) > >> > + indio_dev->dev.of_node = indio_dev->dev.parent->of_node; > >> > + > >> > /* configure elements for the chrdev */ > >> > indio_dev->dev.devt = MKDEV(MAJOR(iio_devt), indio_dev->id); > >> > > >> > diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c > >> > index b289915..795d100 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" > >> > @@ -92,6 +93,164 @@ static const struct iio_chan_spec > >> > return chan; > >> > } > >> > > >> > +#ifdef CONFIG_OF > >> > + > >> > +static int iio_dev_node_match(struct device *dev, void *data) > >> > +{ > >> > + return dev->of_node == data && dev->type == &iio_device_type; > >> > +} > >> > + > >> > +static int __of_iio_channel_get(struct iio_channel *channel, > >> > + struct device_node *np, int index) > >> > +{ > >> > + struct device *idev; > >> > + struct iio_dev *indio_dev; > >> > + int err; > >> > + struct of_phandle_args iiospec; > >> > + > >> > + err = of_parse_phandle_with_args(np, "io-channels", > >> > + "#io-channel-cells", > >> > + index, &iiospec); > >> > + if (err) > >> > + return err; > >> > + > >> > + idev = bus_find_device(&iio_bus_type, NULL, iiospec.np, > >> > + iio_dev_node_match); > >> > + of_node_put(iiospec.np); > >> > + if (idev == NULL) > >> > + return -EPROBE_DEFER; > >> > + > >> > + indio_dev = dev_to_iio_dev(idev); > >> > + channel->indio_dev = indio_dev; > >> > + index = iiospec.args_count ? iiospec.args[0] : 0; > >> > + if (index >= indio_dev->num_channels) { > >> > + return -EINVAL; > >> > + goto err_put; > >> > + } > >> > + channel->channel = &indio_dev->channels[index]; > >> > + > >> > + return 0; > >> > + > >> > +err_put: > >> > + iio_device_put(indio_dev); > >> > + return err; > >> > +} > >> > + > >> > +static struct iio_channel *of_iio_channel_get(struct device_node > >*np, int index) > >> > +{ > >> > + struct iio_channel *channel; > >> > + int err; > >> > + > >> > + if (index < 0) > >> > + return ERR_PTR(-EINVAL); > >> > + > >> > + channel = kzalloc(sizeof(*channel), GFP_KERNEL); > >> > + if (channel == NULL) > >> > + return ERR_PTR(-ENOMEM); > >> > + > >> > + err = __of_iio_channel_get(channel, np, index); > >> > + if (err) > >> > + goto err_free_channel; > >> > + > >> > + return channel; > >> > + > >> > +err_free_channel: > >> > + kfree(channel); > >> > + return ERR_PTR(err); > >> > +} > >> > + > >> > +static struct iio_channel *of_iio_channel_get_by_name(struct > >device_node *np, > >> > + const char *name) > >> > +{ > >> > + struct iio_channel *chan = NULL; > >> > + > >> > + /* Walk up the tree of devices looking for a matching iio channel > >*/ > >> > + while (np) { > >> > + int index = 0; > >> > + > >> > + /* > >> > + * For named iio channels, first look up the name in the > >> > + * "io-channel-names" property. If it cannot be found, the > >> > + * index will be an error code, and of_iio_channel_get() > >> > + * will fail. > >> > + */ > >> > + if (name) > >> > + index = of_property_match_string(np, "io-channel-names", > >> > + name); > >> > + chan = of_iio_channel_get(np, index); > >> > + if (!IS_ERR(chan)) > >> > + break; > >> > + else if (name && index >= 0) { > >> > + pr_err("ERROR: could not get IIO channel %s:%s(%i)\n", > >> > + np->full_name, name ? name : "", index); > >> > + return chan; > >> > + } > >> > + > >> > + /* > >> > + * No matching IIO channel found on this node. > >> > + * If the parent node has a "io-channel-ranges" property, > >> > + * then we can try one of its channels. > >> > + */ > >> > + np = np->parent; > >> > + if (np && !of_get_property(np, "io-channel-ranges", NULL)) > >> > + break; > >> > + } > >> > + return chan; > >> > +} > >> > + > >> > +static struct iio_channel *of_iio_channel_get_all(struct device > >*dev) > >> > +{ > >> > + struct iio_channel *chans; > >> > + int i, mapind, nummaps = 0; > >> > + int ret; > >> > + > >> > + do { > >> > + 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) /* no error, return NULL to search map table */ > >> > + return NULL; > >> > + > >> > + /* NULL terminated array to save passing size */ > >> > + chans = kcalloc(nummaps + 1, sizeof(*chans), GFP_KERNEL); > >> > + if (chans == NULL) > >> > + return ERR_PTR(-ENOMEM); > >> > + > >> > + /* Search for OF matches */ > >> > + for (mapind = 0; mapind < nummaps; mapind++) { > >> > + ret = __of_iio_channel_get(&chans[mapind], dev->of_node, > >> > + mapind); > >> > + if (ret) > >> > + goto error_free_chans; > >> > + } > >> > + return chans; > >> > + > >> > +error_free_chans: > >> > + for (i = 0; i < mapind; i++) > >> > + iio_device_put(chans[i].indio_dev); > >> > + kfree(chans); > >> > + return ERR_PTR(ret); > >> > +} > >> > + > >> > +#else /* CONFIG_OF */ > >> > + > >> > +static inline struct iio_channel * > >> > +of_iio_channel_get_by_name(struct device_node *np, const char > >*name) > >> > +{ > >> > + return NULL; > >> > +} > >> > + > >> > +static inline struct iio_channel *of_iio_channel_get_all(struct > >device *dev) > >> > +{ > >> > + return NULL; > >> > +} > >> > + > >> > +#endif /* CONFIG_OF */ > >> > > >> > static struct iio_channel *iio_channel_get_sys(const char *name, > >> > const char *channel_name) > >> > @@ -150,7 +309,14 @@ struct iio_channel *iio_channel_get(struct > >device *dev, > >> > const char *channel_name) > >> > { > >> > const char *name = dev ? dev_name(dev) : NULL; > >> > + struct iio_channel *channel; > >> > > >> > + if (dev) { > >> > + channel = of_iio_channel_get_by_name(dev->of_node, > >> > + channel_name); > >> > + if (channel != NULL) > >> > + return channel; > >> > + } > >> > return iio_channel_get_sys(name, channel_name); > >> > } > >> > EXPORT_SYMBOL_GPL(iio_channel_get); > >> > @@ -173,6 +339,11 @@ struct iio_channel *iio_channel_get_all(struct > >device *dev) > >> > > >> > if (dev == NULL) > >> > return ERR_PTR(-EINVAL); > >> > + > >> > + chans = of_iio_channel_get_all(dev); > >> > + if (chans) > >> > + return chans; > >> > + > >> > name = dev_name(dev); > >> > > >> > mutex_lock(&iio_map_list_lock); > >> > > >> > >> > > -- > Sent from my Android phone with K-9 Mail. Please excuse my brevity. > -- 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
