Hi all, I forgot to add the link to the discussion that lead to this patch: https://lkml.org/lkml/2014/2/12/306. Jean-Jacques 2014-02-13 10:57 GMT+01:00 Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>: > The goal of this patch is to allow drivers to be probed even if at the time of > the DT parsing some of their ressources are not available yet. > > In the current situation, the resource of a platform device are filled from the > DT at the time the device is created (of_device_alloc()). The drawbackof this > is that a device sitting close to the top of the DT (ahb for example) but > depending on ressources that are initialized later (IRQ domain dynamically > created for example) will fail to probe because the ressources don't exist > at this time. > > This patch fills the resource structure only before the device is probed and > will defer the probe if the resource are not available yet. > > Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx> > Reviewed-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx> > --- > drivers/base/platform.c | 6 ++++ > drivers/of/platform.c | 71 +++++++++++++++++++++++++++++---------------- > include/linux/of_platform.h | 10 +++++++ > 3 files changed, 62 insertions(+), 25 deletions(-) > > diff --git a/drivers/base/platform.c b/drivers/base/platform.c > index bc78848..8e37d8b 100644 > --- a/drivers/base/platform.c > +++ b/drivers/base/platform.c > @@ -481,6 +481,12 @@ static int platform_drv_probe(struct device *_dev) > struct platform_device *dev = to_platform_device(_dev); > int ret; > > + if (_dev->of_node) { > + ret = of_platform_device_populate_resources(dev); > + if (ret < 0) > + return drv->prevent_deferred_probe ? ret : -EPROBE_DEFER; > + } > + > if (ACPI_HANDLE(_dev)) > acpi_dev_pm_attach(_dev, true); > > diff --git a/drivers/of/platform.c b/drivers/of/platform.c > index 404d1da..64a8eb8 100644 > --- a/drivers/of/platform.c > +++ b/drivers/of/platform.c > @@ -141,36 +141,11 @@ struct platform_device *of_device_alloc(struct device_node *np, > struct device *parent) > { > struct platform_device *dev; > - int rc, i, num_reg = 0, num_irq; > - struct resource *res, temp_res; > > dev = platform_device_alloc("", -1); > if (!dev) > return NULL; > > - /* count the io and irq resources */ > - if (of_can_translate_address(np)) > - while (of_address_to_resource(np, num_reg, &temp_res) == 0) > - num_reg++; > - num_irq = of_irq_count(np); > - > - /* Populate the resource table */ > - if (num_irq || num_reg) { > - res = kzalloc(sizeof(*res) * (num_irq + num_reg), GFP_KERNEL); > - if (!res) { > - platform_device_put(dev); > - return NULL; > - } > - > - dev->num_resources = num_reg + num_irq; > - dev->resource = res; > - for (i = 0; i < num_reg; i++, res++) { > - rc = of_address_to_resource(np, i, res); > - WARN_ON(rc); > - } > - WARN_ON(of_irq_to_resource_table(np, res, num_irq) != num_irq); > - } > - > dev->dev.of_node = of_node_get(np); > #if defined(CONFIG_MICROBLAZE) > dev->dev.dma_mask = &dev->archdata.dma_mask; > @@ -233,6 +208,52 @@ static struct platform_device *of_platform_device_create_pdata( > return dev; > } > > +int of_platform_device_populate_resources(struct platform_device *dev) > +{ > + struct device_node *np; > + int rc = 0, i, nreg = 0, nirq; > + > + np = dev->dev.of_node; > + > + /* count the io and irq resources */ > + if (of_can_translate_address(np)) { > + struct resource temp_res; > + while (of_address_to_resource(np, nreg, &temp_res) == 0) > + nreg++; > + } > + nirq = of_irq_count(np); > + > + /* Populate the resource table */ > + if (nirq || nreg) { > + struct resource *res; > + > + res = krealloc(dev->resource, sizeof(*res) * (nirq + nreg), > + GFP_KERNEL); > + if (!res) { > + kfree(dev->resource); > + dev->resource = NULL; > + return -ENOMEM; > + } > + memset(res, 0, sizeof(*res) * (nirq + nreg)); > + dev->resource = res; > + dev->num_resources = nreg + nirq; > + > + for (i = 0; i < nreg; i++, res++) { > + rc = of_address_to_resource(np, i, res); > + WARN_ON(rc); > + if (rc) > + break; > + } > + > + if (!rc && of_irq_to_resource_table(np, res, nirq) != nirq) { > + rc = -ENOENT; > + WARN_ON(rc); > + } > + } > + return rc; > +} > +EXPORT_SYMBOL(of_platform_device_populate_resources); > + > /** > * of_platform_device_create - Alloc, initialize and register an of_device > * @np: pointer to node to create device for > diff --git a/include/linux/of_platform.h b/include/linux/of_platform.h > index 05cb4a9..315e1e3 100644 > --- a/include/linux/of_platform.h > +++ b/include/linux/of_platform.h > @@ -53,6 +53,16 @@ struct of_dev_auxdata { > > extern const struct of_device_id of_default_bus_match_table[]; > > +/* Populate the resource for a platform device */ > +#ifdef CONFIG_OF > +int of_platform_device_populate_resources(struct platform_device *dev); > +#else > +static inline int of_platform_device_populate_resources( > + struct platform_device *) > +{ > + return -ENOSYS; > +} > +#endif > /* Platform drivers register/unregister */ > extern struct platform_device *of_device_alloc(struct device_node *np, > const char *bus_id, > -- > 1.8.5.3 > -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
