From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753053AbaJTOFT (ORCPT ); Mon, 20 Oct 2014 10:05:19 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:55154 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752345AbaJTOFR (ORCPT ); Mon, 20 Oct 2014 10:05:17 -0400 From: Grant Likely Subject: Re: [PATCH v5 03/12] ACPI: Allow drivers to match using Device Tree compatible property To: "Rafael J. Wysocki" , Linux Kernel Mailing List Cc: Greg Kroah-Hartman , Arnd Bergmann , Mika Westerberg , ACPI Devel Maling List , Aaron Lu , devicetree@vger.kernel.org, Linus Walleij , Alexandre Courbot , Dmitry Torokhov , Bryan Wu , Darren Hart , Mark Rutland In-Reply-To: <3167500.xrhugPHshV@vostro.rjw.lan> References: <2660541.BycO7TFnA2@vostro.rjw.lan> <11223831.j9KAEfSQsY@vostro.rjw.lan> <3167500.xrhugPHshV@vostro.rjw.lan> Date: Mon, 20 Oct 2014 16:05:01 +0200 Message-Id: <20141020140501.D10A5C40982@trevor.secretlab.ca> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 17 Oct 2014 14:05:59 +0200 , "Rafael J. Wysocki" wrote: > From: Mika Westerberg > > We have lots of existing Device Tree enabled drivers and allocating > separate _HID for each is not feasible. Instead we allocate special _HID > "PRP0001" that means that the match should be done using Device Tree > compatible property using driver's .of_match_table instead if the driver > is missing .acpi_match_table. (Not a critique of this patch, but merely a helpful comment; my previous ack remains intact) :-) It would be useful for the code to point at some document that describes the semantics of the PRP0001 binding. g. > > If there is a need to distinguish from where the device is enumerated > (DT/ACPI) driver can check dev->of_node or ACPI_COMPATION(dev). > > Signed-off-by: Mika Westerberg > Reviewed-by: Grant Likely > Signed-off-by: Rafael J. Wysocki > --- > drivers/acpi/property.c | 34 +++++++++++++++++ > drivers/acpi/scan.c | 97 +++++++++++++++++++++++++++++++++++++++++++------ > include/acpi/acpi_bus.h | 1 + > include/linux/acpi.h | 8 +--- > 4 files changed, 123 insertions(+), 17 deletions(-) > > diff --git a/drivers/acpi/property.c b/drivers/acpi/property.c > index 680f7f1..ff53eb8 100644 > --- a/drivers/acpi/property.c > +++ b/drivers/acpi/property.c > @@ -76,6 +76,37 @@ static bool acpi_properties_format_valid(const union acpi_object *properties) > return true; > } > > +static void acpi_init_of_compatible(struct acpi_device *adev) > +{ > + const union acpi_object *of_compatible; > + struct acpi_hardware_id *hwid; > + bool acpi_of = false; > + > + /* > + * Check if the special PRP0001 ACPI ID is present and in that > + * case we fill in Device Tree compatible properties for this > + * device. > + */ > + list_for_each_entry(hwid, &adev->pnp.ids, list) { > + if (!strcmp(hwid->id, "PRP0001")) { > + acpi_of = true; > + break; > + } > + } > + > + if (!acpi_of) > + return; > + > + if (acpi_dev_get_property_array(adev, "compatible", ACPI_TYPE_STRING, > + &of_compatible)) { > + acpi_handle_warn(adev->handle, > + "PRP0001 requires compatible property\n"); > + return; > + } > + > + adev->data.of_compatible = of_compatible; > +} > + > void acpi_init_properties(struct acpi_device *adev) > { > struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; > @@ -119,6 +150,8 @@ void acpi_init_properties(struct acpi_device *adev) > > adev->data.pointer = buf.pointer; > adev->data.properties = properties; > + > + acpi_init_of_compatible(adev); > return; > } > > @@ -130,6 +163,7 @@ void acpi_init_properties(struct acpi_device *adev) > void acpi_free_properties(struct acpi_device *adev) > { > ACPI_FREE((void *)adev->data.pointer); > + adev->data.of_compatible = NULL; > adev->data.pointer = NULL; > adev->data.properties = NULL; > } > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 1979ab3..bc999f1 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -124,17 +124,51 @@ static int create_modalias(struct acpi_device *acpi_dev, char *modalias, > if (list_empty(&acpi_dev->pnp.ids)) > return 0; > > - len = snprintf(modalias, size, "acpi:"); > - size -= len; > - > - list_for_each_entry(id, &acpi_dev->pnp.ids, list) { > - count = snprintf(&modalias[len], size, "%s:", id->id); > - if (count < 0) > - return -EINVAL; > - if (count >= size) > - return -ENOMEM; > - len += count; > - size -= count; > + /* > + * If the device has PRP0001 we expose DT compatible modalias > + * instead in form of of:NnameTCcompatible. > + */ > + if (acpi_dev->data.of_compatible) { > + struct acpi_buffer buf = { ACPI_ALLOCATE_BUFFER }; > + const union acpi_object *of_compatible, *obj; > + char *c; > + int i; > + > + acpi_get_name(acpi_dev->handle, ACPI_SINGLE_NAME, &buf); > + /* DT strings are all in lower case */ > + for (c = buf.pointer; *c != '\0'; c++) > + *c = tolower(*c); > + > + len = snprintf(modalias, size, "of:N%sT", (char *)buf.pointer); > + ACPI_FREE(buf.pointer); > + > + of_compatible = acpi_dev->data.of_compatible; > + for (i = 0; i < of_compatible->package.count; i++) { > + obj = &of_compatible->package.elements[i]; > + > + count = snprintf(&modalias[len], size, "C%s", > + obj->string.pointer); > + if (count < 0) > + return -EINVAL; > + if (count >= size) > + return -ENOMEM; > + > + len += count; > + size -= count; > + } > + } else { > + len = snprintf(modalias, size, "acpi:"); > + size -= len; > + > + list_for_each_entry(id, &acpi_dev->pnp.ids, list) { > + count = snprintf(&modalias[len], size, "%s:", id->id); > + if (count < 0) > + return -EINVAL; > + if (count >= size) > + return -ENOMEM; > + len += count; > + size -= count; > + } > } > > modalias[len] = '\0'; > @@ -864,6 +898,47 @@ int acpi_match_device_ids(struct acpi_device *device, > } > EXPORT_SYMBOL(acpi_match_device_ids); > > +/* Performs match against special "PRP0001" shoehorn ACPI ID */ > +static bool acpi_of_driver_match_device(struct device *dev, > + const struct device_driver *drv) > +{ > + const union acpi_object *of_compatible; > + struct acpi_device *adev; > + int i; > + > + adev = ACPI_COMPANION(dev); > + if (!adev) > + return false; > + > + of_compatible = adev->data.of_compatible; > + if (!drv->of_match_table || !of_compatible) > + return false; > + > + /* Now we can look for the driver DT compatible strings */ > + for (i = 0; i < of_compatible->package.count; i++) { > + const struct of_device_id *id; > + const union acpi_object *obj; > + > + obj = &of_compatible->package.elements[i]; > + > + for (id = drv->of_match_table; id->compatible[0]; id++) > + if (!strcasecmp(obj->string.pointer, id->compatible)) > + return true; > + } > + > + return false; > +} > + > +bool acpi_driver_match_device(struct device *dev, > + const struct device_driver *drv) > +{ > + if (!drv->acpi_match_table) > + return acpi_of_driver_match_device(dev, drv); > + > + return !!acpi_match_device(drv->acpi_match_table, dev); > +} > +EXPORT_SYMBOL_GPL(acpi_driver_match_device); > + > static void acpi_free_power_resources_lists(struct acpi_device *device) > { > int i; > diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h > index f9734fa..98cd723 100644 > --- a/include/acpi/acpi_bus.h > +++ b/include/acpi/acpi_bus.h > @@ -341,6 +341,7 @@ struct acpi_device_physical_node { > struct acpi_device_data { > const union acpi_object *pointer; > const union acpi_object *properties; > + const union acpi_object *of_compatible; > }; > > /* Device */ > diff --git a/include/linux/acpi.h b/include/linux/acpi.h > index 18c1bc3..11aa6b8 100644 > --- a/include/linux/acpi.h > +++ b/include/linux/acpi.h > @@ -424,12 +424,8 @@ extern int acpi_nvs_for_each_region(int (*func)(__u64, __u64, void *), > const struct acpi_device_id *acpi_match_device(const struct acpi_device_id *ids, > const struct device *dev); > > -static inline bool acpi_driver_match_device(struct device *dev, > - const struct device_driver *drv) > -{ > - return !!acpi_match_device(drv->acpi_match_table, dev); > -} > - > +extern bool acpi_driver_match_device(struct device *dev, > + const struct device_driver *drv); > int acpi_device_uevent_modalias(struct device *, struct kobj_uevent_env *); > int acpi_device_modalias(struct device *, char *, int); > > -- > 1.9.3 > >