From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932334AbcGGW1i (ORCPT ); Thu, 7 Jul 2016 18:27:38 -0400 Received: from mail-pa0-f44.google.com ([209.85.220.44]:33418 "EHLO mail-pa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932185AbcGGWVX (ORCPT ); Thu, 7 Jul 2016 18:21:23 -0400 From: Stephen Boyd To: linux-usb@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Andy Gross , Bjorn Andersson , Neil Armstrong , Arnd Bergmann , Felipe Balbi , Greg Kroah-Hartman , Heikki Krogerus , devicetree@vger.kernel.org, Rob Herring Subject: [PATCH v2 03/22] usb: ulpi: Support device discovery via device properties Date: Thu, 7 Jul 2016 15:20:54 -0700 Message-Id: <20160707222114.1673-4-stephen.boyd@linaro.org> X-Mailer: git-send-email 2.9.0.rc2.8.ga28705d In-Reply-To: <20160707222114.1673-1-stephen.boyd@linaro.org> References: <20160707222114.1673-1-stephen.boyd@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The qcom HSIC ULPI phy doesn't have any bits set in the vendor or product ID registers. This makes it impossible to make a ULPI driver match against the ID registers. Add support to discover the ULPI phys via DT/device properties to help alleviate this problem. In the DT case, we'll look for a ULPI bus node underneath the device registering the ULPI viewport (or the parent of that device to support chipidea's device layout) and then match up the phy node underneath that with the ULPI device that's created. The side benefit of this is that we can use standard properties in the phy node like clks, regulators, gpios, etc. because we don't have firmware like ACPI to turn these things on for us. And we can use the DT phy binding to point our phy consumer to the phy provider. Furthermore, this avoids any problems with reading the ID registers before the phy is powered up. The ULPI bus supports native enumeration by reading the vendor ID and product ID registers at device creation time, but we can't be certain that those register reads will succeed if the phy is not powered. If the ULPI spec had some generic power sequencing for these registers we could put that into the ULPI bus layer and power up the device before reading the ID registers. Unfortunately this doesn't exist and the power sequence is usually device specific. By having the vendor and product ID properties in ACPI or DT, we can match up devices with drivers without having to read the hardware before it's powered up and avoid this problem. Cc: Greg Kroah-Hartman Cc: Heikki Krogerus Cc: Cc: Rob Herring Signed-off-by: Stephen Boyd --- Documentation/devicetree/bindings/usb/ulpi.txt | 35 ++++++++++++ drivers/usb/common/ulpi.c | 74 +++++++++++++++++++++++++- 2 files changed, 107 insertions(+), 2 deletions(-) create mode 100644 Documentation/devicetree/bindings/usb/ulpi.txt diff --git a/Documentation/devicetree/bindings/usb/ulpi.txt b/Documentation/devicetree/bindings/usb/ulpi.txt new file mode 100644 index 000000000000..c649ca5b0996 --- /dev/null +++ b/Documentation/devicetree/bindings/usb/ulpi.txt @@ -0,0 +1,35 @@ +ULPI bus binding +---------------- + +Phys that are behind a ULPI connection can be described with the following +binding. The host controller shall have a "ulpi" named node as a child, and +that node shall have one enabled node underneath it representing the ulpi +device on the bus. + +PROPERTIES +---------- + +- ulpi-vendor: + Usage: optional + Value type: + Definition: The USB-IF assigned vendor id for this device + +- ulpi-product: + Usage: required if ulpi-vendor is present + Value type: + Definition: The vendor assigned product id for this device + +EXAMPLE +------- + +usb { + compatible = "vendor,usb-controller"; + + ulpi { + phy { + compatible = "vendor,phy"; + ulpi-vendor = /bits/ 16 <0x1d6b>; + ulpi-product = /bits/ 16 <0x0002>; + }; + }; +}; diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c index 01c0c0477a9e..3e8dd7b57aaf 100644 --- a/drivers/usb/common/ulpi.c +++ b/drivers/usb/common/ulpi.c @@ -16,6 +16,9 @@ #include #include #include +#include +#include +#include /* -------------------------------------------------------------------------- */ @@ -39,6 +42,10 @@ static int ulpi_match(struct device *dev, struct device_driver *driver) struct ulpi *ulpi = to_ulpi_dev(dev); const struct ulpi_device_id *id; + /* Some ULPI devices don't have a product id so rely on OF match */ + if (ulpi->id.product == 0) + return of_driver_match_device(dev, driver); + for (id = drv->id_table; id->vendor; id++) if (id->vendor == ulpi->id.vendor && id->product == ulpi->id.product) @@ -50,6 +57,11 @@ static int ulpi_match(struct device *dev, struct device_driver *driver) static int ulpi_uevent(struct device *dev, struct kobj_uevent_env *env) { struct ulpi *ulpi = to_ulpi_dev(dev); + int ret; + + ret = of_device_uevent_modalias(dev, env); + if (ret != -ENODEV) + return ret; if (add_uevent_var(env, "MODALIAS=ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product)) @@ -60,6 +72,11 @@ static int ulpi_uevent(struct device *dev, struct kobj_uevent_env *env) static int ulpi_probe(struct device *dev) { struct ulpi_driver *drv = to_ulpi_driver(dev->driver); + int ret; + + ret = of_clk_set_defaults(dev->of_node, false); + if (ret < 0) + return ret; return drv->probe(to_ulpi_dev(dev)); } @@ -87,8 +104,13 @@ static struct bus_type ulpi_bus = { static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf) { + int len; struct ulpi *ulpi = to_ulpi_dev(dev); + len = of_device_get_modalias(dev, buf, PAGE_SIZE - 1); + if (len != -ENODEV) + return len; + return sprintf(buf, "ulpi:v%04xp%04x\n", ulpi->id.vendor, ulpi->id.product); } @@ -152,7 +174,29 @@ EXPORT_SYMBOL_GPL(ulpi_unregister_driver); /* -------------------------------------------------------------------------- */ -static int ulpi_register(struct device *dev, struct ulpi *ulpi) +static int ulpi_of_register(struct ulpi *ulpi) +{ + struct device_node *np = NULL, *child; + + /* Find a ulpi bus underneath the parent or the parent of the parent */ + if (ulpi->dev.parent->of_node) + np = of_find_node_by_name(ulpi->dev.parent->of_node, "ulpi"); + else if (ulpi->dev.parent->parent && ulpi->dev.parent->parent->of_node) + np = of_find_node_by_name(ulpi->dev.parent->parent->of_node, + "ulpi"); + if (!np) + return 0; + + child = of_get_next_available_child(np, NULL); + if (!child) + return -EINVAL; + + ulpi->dev.of_node = child; + + return 0; +} + +static int ulpi_read_id(struct ulpi *ulpi) { int ret; @@ -174,14 +218,39 @@ static int ulpi_register(struct device *dev, struct ulpi *ulpi) ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW); ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8; + return 0; +} + +static int ulpi_register(struct device *dev, struct ulpi *ulpi) +{ + int ret; + ulpi->dev.parent = dev; ulpi->dev.bus = &ulpi_bus; ulpi->dev.type = &ulpi_dev_type; dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev)); + if (IS_ENABLED(CONFIG_OF)) { + ret = ulpi_of_register(ulpi); + if (ret) + return ret; + } + ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev)); - request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); + ret = device_property_read_u16(&ulpi->dev, "ulpi-vendor", + &ulpi->id.vendor); + ret |= device_property_read_u16(&ulpi->dev, "ulpi-product", + &ulpi->id.product); + if (ret) { + ret = ulpi_read_id(ulpi); + if (ret) + return ret; + } + + if (of_device_request_module(&ulpi->dev)) + request_module("ulpi:v%04xp%04x", ulpi->id.vendor, + ulpi->id.product); ret = device_register(&ulpi->dev); if (ret) @@ -232,6 +301,7 @@ EXPORT_SYMBOL_GPL(ulpi_register_interface); */ void ulpi_unregister_interface(struct ulpi *ulpi) { + of_node_put(ulpi->dev.of_node); device_unregister(&ulpi->dev); } EXPORT_SYMBOL_GPL(ulpi_unregister_interface); -- 2.9.0.rc2.8.ga28705d