| Message ID | 20161226181153.11271-2-bjorn.andersson@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
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. [..] > > static int lm3533_i2c_probe(struct i2c_client *i2c, > > const struct i2c_device_id *id) > > { [..] > > > > + 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. > I agree, will update this. > > + ret = lm3533_pdata_from_of_node(lm3533->dev); > > + if (ret < 0) > > + return ret; > > + } > > + > > return lm3533_device_init(lm3533); > > } > > Regards, Bjorn
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? -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog
On Fri, 06 Jan 2017, Bjorn Andersson wrote: > 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. Very well, but can you add a comment describing the reason for its existence with a view to removing it further down the line? -- Lee Jones Linaro STMicroelectronics Landing Team Lead Linaro.org │ Open source software for ARM SoCs Follow Linaro: Facebook | Twitter | Blog
On Mon 09 Jan 00:36 PST 2017, Lee Jones wrote: > On Fri, 06 Jan 2017, Bjorn Andersson wrote: > > > 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. > > Very well, but can you add a comment describing the reason for its > existence with a view to removing it further down the line? > Sounds reasonable, I will prepare an updated patch with this. Regards, Bjorn
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); + } + 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) { + ret = lm3533_pdata_from_of_node(lm3533->dev); + if (ret < 0) + return ret; + } + return lm3533_device_init(lm3533); }