Message ID | 20161226181153.11271-1-bjorn.andersson@linaro.org |
---|---|
State | New |
Headers | show |
On Mon 2016-12-26 10:11:51, Bjorn Andersson wrote: > From: Bjorn Andersson <bjorn.andersson@sonymobile.com> > > Implement support for initialization of the lm3533 backlight from Device > Tree. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> Acked-by: Pavel Machek <pavel@ucw.cz> -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
On Mon, 26 Dec 2016, Bjorn Andersson wrote: > From: Bjorn Andersson <bjorn.andersson@sonymobile.com> > > Implement support for initialization of the lm3533 driver core and > probing child devices from Device Tree. > > Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com> > Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org> > --- > > Changes since v3: > - Moved parsing of child of nodes into each child driver > - Use of_platform_populate() to instanciate child devices > > drivers/mfd/lm3533-core.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 76 insertions(+) > > diff --git a/drivers/mfd/lm3533-core.c b/drivers/mfd/lm3533-core.c > index 5abcbb2e8849..f147677f05ff 100644 > --- a/drivers/mfd/lm3533-core.c > +++ b/drivers/mfd/lm3533-core.c > @@ -18,6 +18,8 @@ > #include <linux/gpio.h> > #include <linux/i2c.h> > #include <linux/mfd/core.h> > +#include <linux/of_gpio.h> > +#include <linux/of_platform.h> > #include <linux/regmap.h> > #include <linux/seq_file.h> > #include <linux/slab.h> > @@ -512,6 +514,11 @@ static int lm3533_device_init(struct lm3533 *lm3533) > lm3533_device_bl_init(lm3533); > lm3533_device_led_init(lm3533); > > + if (lm3533->dev->of_node) { > + of_platform_populate(lm3533->dev->of_node, NULL, NULL, > + lm3533->dev); > + } I think it's save to call of_platform_populate(), even if !of_node. It will just fail and return an error code, which you are ignoring anyway. > ret = sysfs_create_group(&lm3533->dev->kobj, &lm3533_attribute_group); > if (ret < 0) { > dev_err(lm3533->dev, "failed to create sysfs attributes\n"); > @@ -588,10 +595,73 @@ static const struct regmap_config regmap_config = { > .precious_reg = lm3533_precious_register, > }; > > +static int lm3533_of_parse_enum(struct device *dev, const char *propname, > + const unsigned int *match, size_t num_matches) > +{ > + size_t i; > + int ret; > + u32 val; > + > + ret = of_property_read_u32(dev->of_node, propname, &val); > + if (ret < 0) { > + dev_err(dev, "failed to parse %s\n", propname); > + return ret; > + } > + > + for (i = 0; i < num_matches; i++) { > + if (val == match[i]) > + return i; > + } > + > + dev_err(dev, "unsupported value of %s\n", propname); > + return -EINVAL; > +} > + > +static int lm3533_pdata_from_of_node(struct device *dev) > +{ > + struct lm3533_platform_data *pdata; > + int ret; > + const unsigned int freqs[] = { > + [LM3533_BOOST_FREQ_500KHZ] = 500000, > + [LM3533_BOOST_FREQ_1000KHZ] = 1000000, > + }; > + const unsigned int ovps[] = { > + [LM3533_BOOST_OVP_16V] = 16000, > + [LM3533_BOOST_OVP_24V] = 24000, > + [LM3533_BOOST_OVP_32V] = 32000, > + [LM3533_BOOST_OVP_40V] = 40000, > + }; > + > + pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL); > + if (!pdata) > + return -ENOMEM; > + > + pdata->gpio_hwen = of_get_named_gpio(dev->of_node, "hwen-gpios", 0); > + if (pdata->gpio_hwen < 0) > + return pdata->gpio_hwen; > + > + ret = lm3533_of_parse_enum(dev, "ti,boost-freq-hz", > + freqs, ARRAY_SIZE(freqs)); > + if (ret < 0) > + return ret; > + pdata->boost_freq = ret; > + > + ret = lm3533_of_parse_enum(dev, "ti,boost-ovp-mv", > + ovps, ARRAY_SIZE(ovps)); > + if (ret < 0) > + return ret; > + pdata->boost_ovp = ret; > + > + dev->platform_data = pdata; > + > + return 0; > +} > + > static int lm3533_i2c_probe(struct i2c_client *i2c, > const struct i2c_device_id *id) > { > struct lm3533 *lm3533; > + int ret; > > dev_dbg(&i2c->dev, "%s\n", __func__); > > @@ -608,6 +678,12 @@ static int lm3533_i2c_probe(struct i2c_client *i2c, > lm3533->dev = &i2c->dev; > lm3533->irq = i2c->irq; > > + if (i2c->dev.of_node) { I'd prefer this check to be placed in lm3533_pdata_from_of_node(). Just return silently if !dev->of_node. > + ret = lm3533_pdata_from_of_node(lm3533->dev); > + if (ret < 0) > + return ret; > + } > + > return lm3533_device_init(lm3533); > } > -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri 06 Jan 01:53 PST 2017, Lee Jones wrote: > On Thu, 05 Jan 2017, Bjorn Andersson wrote: > > > On Wed 04 Jan 23:49 PST 2017, Lee Jones wrote: > > > > > On Wed, 04 Jan 2017, Bjorn Andersson wrote: > > > > > > > On Wed 04 Jan 03:54 PST 2017, Lee Jones wrote: > > > > > > > > > On Mon, 26 Dec 2016, Bjorn Andersson wrote: > > > > > > > > > > > From: Bjorn Andersson <bjorn.andersson@sonymobile.com> > > > > > > > > > > > > Implement support for initialization of the lm3533 driver core and > > > > > > probing child devices from Device Tree. > > > > > > > > > > > > > > [..] > > > > > > > > > > @@ -512,6 +514,11 @@ static int lm3533_device_init(struct lm3533 *lm3533) > > > > > > lm3533_device_bl_init(lm3533); > > > > > > lm3533_device_led_init(lm3533); > > > > > > > > > > > > + if (lm3533->dev->of_node) { > > > > > > + of_platform_populate(lm3533->dev->of_node, NULL, NULL, > > > > > > + lm3533->dev); > > > > > > + } > > > > > > > > > > I think it's save to call of_platform_populate(), even if !of_node. > > > > > It will just fail and return an error code, which you are ignoring > > > > > anyway. > > > > > > > > > > > > > I thought so too, but that's apparently how you trigger probing children > > > > of the root node. So we're stuck with a conditional. > > > > > > Ah, so this is to protect against the case where DT is present, but a > > > node for this device is not (or is disabled), so is left unprobed. > > > Then the bind is initiated via I2C? Or something else? > > > > > > > In the event that a new lm3533 is spawned from sysfs we would not have > > platform_data when entering lm3533_device_init() and just bail early. > > > > Therefor, this issue would be limited to the odd case of lm3533 being > > initiated from code (e.g. a board file) on a DT enabled system. In which > > case it will create and probe new devices from the root of the DT. > > Eewww, do we really want to support that? > As long as we support non-DT probing of the driver this is a possible scenario. And with modern ARM being DT-centric I think that if anyone uses this driver with a modern version of the Linux kernel it's likely that they would have this kind of hybrid solution. So, although ugly, I think we should keep this conditional and hope that anyone using the driver will transition to use the DT binding. Regards, Bjorn -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/devicetree/bindings/mfd/lm3533.txt b/Documentation/devicetree/bindings/mfd/lm3533.txt new file mode 100644 index 000000000000..909281096ba2 --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/lm3533.txt @@ -0,0 +1,205 @@ +Texas Instruments LM3533 binding + +This binding describes the Texas Instruments LM3533, a lighting power solution +for smartphone handsets. The common properties are described directly in the +node, while each individual component are described in an optional subnode. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be: + "ti,lm3533" + +- reg: + Usage: required + Value type: <u32> + Definition: i2c address of the LM3533 chip + +- als-supply: + Usage: optional + Value type: <prop-encoded-array> + Definition: reference to regulator powering the V_als input; as + specified in "../regulator/regulator.txt" + +- hwen-gpios: + Usage: required + Value type: <prop-encoded-array> + Definition: reference to gpio pin connected to the HWEN input; as + specified in "../gpio/gpio.txt" + +- ti,boost-freq-hz: + Usage: required + Value type: <u32> + Definition: switch-frequency of the boost converter, must be either: + 500000 or 1000000 + +- ti,boost-ovp-mv: + Usage: required + Value type: <u32> + Definition: over-voltage protection limit, in mV. Must be one of: + 16000, 24000, 32000 or 40000 + +- #address-cells: + Usage: required + Value type: <u32> + Definition: must be 1 + +- #size-cells: + Usage: required + Value type: <u32> + Definition: must be 0 + += ALS SUBNODE +The ambient light sensor subnode carrying the light sensor related properties. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be: + "ti,lm3533-als" + +- ti,als-resistance-ohm: + Usage: required (unless ti,pwm-mode is specified) + Value type: <u32> + Definition: specifies the resistor value (R_als), in Ohm. Valid values + ranges from 200000 to 1574 Ohm. + +- ti,pwm-mode: + Usage: optional + Value type: <empty> + Definition: specifies, if present, that the als should operate in PWM + mode - rather than analog mode + += BACKLIGHT NODES +Backlight subnodes carrying the backlight related properties. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be: + "ti,lm3533-backlight" + +- reg: + Usage: required + Value type: <u32> + Definition: specifies which of the two backlights this node corresponds + to + +- default-brightness: + Usage: optional + Value type: <32> + Definition: specifies the default brightness for the backlight, in + units of brightness [0-255] + +- label: + Usage: required + Value type: <string> + Definition: specifies a name of this backlight + +- led-max-microamp: + Usage: required + Value type: <u32> + Definition: specifies the max current for this backlight, in uA, as + described in "../leds/common.txt" + +- ti,pwm-zones: + Usage: optional + Value type: <u32 list> + Definition: lists the ALS zones to be PWM controlled for this backlight, + the values in the list are in the range [0 - 4] + += LED NODES +LED subnodes carrying the LED related properties. + +- compatible: + Usage: required + Value type: <stringlist> + Definition: must be: + "ti,lm3533-led" + +- reg: + Usage: required + Value type: <u32> + Definition: specifies which of the four LEDs this node corresponds to + +- linux,default-trigger: + Usage: optional + Value type: <string> + Definition: specifies the default trigger for the LED, as described in + "../leds/common.txt" + +- label: + Usage: required + Value type: <string> + Definition: specifies a name of this LED, as described in + "../leds/common.txt" + +- led-max-microamp: + Usage: required + Value type: <u32> + Definition: specifies the max current for this LED, in uA, as described + in "../leds/common.txt" + +- ti,pwm-zones: + Usage: optional + Value type: <u32 list> + Definition: lists the ALS zones to be PWM controlled for this LED, the + values in the list are in the range [0 - 4] + += EXAMPLE + +i2c@12460000 { + compatible = "qcom,i2c-qup-v1.1.1"; + ... + + lm3533@36 { + compatible = "ti,lm3533"; + reg = <0x36>; + + als-supply = <&pm8921_l11>; + hwen-gpios = <&pm8921_gpio 26 GPIO_ACTIVE_HIGH>; + + ti,boost-freq-hz = <500000>; + ti,boost-ovp-mv = <24000>; + + #address-cells = <1>; + #size-cells = <0>; + + als { + compatible = "ti,lm3533-als"; + ti,als-resistance-ohm = <200000>; + }; + + backlight@0 { + compatible = "ti,lm3533-backlight"; + reg = <0>; + label = "backlight"; + + led-max-microamp = <20200>; + }; + + led@0 { + compatible = "ti,lm3533-led"; + reg = <0>; + label = "red"; + + led-max-microamp = <5000>; + }; + + led@1 { + compatible = "ti,lm3533-led"; + reg = <1>; + label = "green"; + + led-max-microamp = <5000>; + }; + + led@2 { + compatible = "ti,lm3533-led"; + reg = <2>; + label = "blue"; + + led-max-microamp = <5000>; + }; + }; +