diff options
Diffstat (limited to 'drivers/usb/common/ulpi.c')
-rw-r--r-- | drivers/usb/common/ulpi.c | 380 |
1 files changed, 380 insertions, 0 deletions
diff --git a/drivers/usb/common/ulpi.c b/drivers/usb/common/ulpi.c new file mode 100644 index 000000000..38703781e --- /dev/null +++ b/drivers/usb/common/ulpi.c @@ -0,0 +1,380 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ulpi.c - USB ULPI PHY bus + * + * Copyright (C) 2015 Intel Corporation + * + * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> + */ + +#include <linux/ulpi/interface.h> +#include <linux/ulpi/driver.h> +#include <linux/ulpi/regs.h> +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/acpi.h> +#include <linux/debugfs.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/clk/clk-conf.h> + +/* -------------------------------------------------------------------------- */ + +int ulpi_read(struct ulpi *ulpi, u8 addr) +{ + return ulpi->ops->read(ulpi->dev.parent, addr); +} +EXPORT_SYMBOL_GPL(ulpi_read); + +int ulpi_write(struct ulpi *ulpi, u8 addr, u8 val) +{ + return ulpi->ops->write(ulpi->dev.parent, addr, val); +} +EXPORT_SYMBOL_GPL(ulpi_write); + +/* -------------------------------------------------------------------------- */ + +static int ulpi_match(struct device *dev, struct device_driver *driver) +{ + struct ulpi_driver *drv = to_ulpi_driver(driver); + struct ulpi *ulpi = to_ulpi_dev(dev); + const struct ulpi_device_id *id; + + /* + * Some ULPI devices don't have a vendor id + * or provide an id_table so rely on OF match. + */ + if (ulpi->id.vendor == 0 || !drv->id_table) + 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) + return 1; + + return 0; +} + +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)) + return -ENOMEM; + return 0; +} + +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)); +} + +static void ulpi_remove(struct device *dev) +{ + struct ulpi_driver *drv = to_ulpi_driver(dev->driver); + + if (drv->remove) + drv->remove(to_ulpi_dev(dev)); +} + +static struct bus_type ulpi_bus = { + .name = "ulpi", + .match = ulpi_match, + .uevent = ulpi_uevent, + .probe = ulpi_probe, + .remove = ulpi_remove, +}; + +/* -------------------------------------------------------------------------- */ + +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_modalias(dev, buf, PAGE_SIZE); + if (len != -ENODEV) + return len; + + return sprintf(buf, "ulpi:v%04xp%04x\n", + ulpi->id.vendor, ulpi->id.product); +} +static DEVICE_ATTR_RO(modalias); + +static struct attribute *ulpi_dev_attrs[] = { + &dev_attr_modalias.attr, + NULL +}; + +static const struct attribute_group ulpi_dev_attr_group = { + .attrs = ulpi_dev_attrs, +}; + +static const struct attribute_group *ulpi_dev_attr_groups[] = { + &ulpi_dev_attr_group, + NULL +}; + +static void ulpi_dev_release(struct device *dev) +{ + of_node_put(dev->of_node); + kfree(to_ulpi_dev(dev)); +} + +static const struct device_type ulpi_dev_type = { + .name = "ulpi_device", + .groups = ulpi_dev_attr_groups, + .release = ulpi_dev_release, +}; + +/* -------------------------------------------------------------------------- */ + +/** + * __ulpi_register_driver - register a driver with the ULPI bus + * @drv: driver being registered + * @module: ends up being THIS_MODULE + * + * Registers a driver with the ULPI bus. + */ +int __ulpi_register_driver(struct ulpi_driver *drv, struct module *module) +{ + if (!drv->probe) + return -EINVAL; + + drv->driver.owner = module; + drv->driver.bus = &ulpi_bus; + + return driver_register(&drv->driver); +} +EXPORT_SYMBOL_GPL(__ulpi_register_driver); + +/** + * ulpi_unregister_driver - unregister a driver with the ULPI bus + * @drv: driver to unregister + * + * Unregisters a driver with the ULPI bus. + */ +void ulpi_unregister_driver(struct ulpi_driver *drv) +{ + driver_unregister(&drv->driver); +} +EXPORT_SYMBOL_GPL(ulpi_unregister_driver); + +/* -------------------------------------------------------------------------- */ + +static int ulpi_of_register(struct ulpi *ulpi) +{ + struct device_node *np = NULL, *child; + struct device *parent; + + /* Find a ulpi bus underneath the parent or the grandparent */ + parent = ulpi->dev.parent; + if (parent->of_node) + np = of_get_child_by_name(parent->of_node, "ulpi"); + else if (parent->parent && parent->parent->of_node) + np = of_get_child_by_name(parent->parent->of_node, "ulpi"); + if (!np) + return 0; + + child = of_get_next_available_child(np, NULL); + of_node_put(np); + if (!child) + return -EINVAL; + + ulpi->dev.of_node = child; + + return 0; +} + +static int ulpi_read_id(struct ulpi *ulpi) +{ + int ret; + + /* Test the interface */ + ret = ulpi_write(ulpi, ULPI_SCRATCH, 0xaa); + if (ret < 0) + goto err; + + ret = ulpi_read(ulpi, ULPI_SCRATCH); + if (ret < 0) + return ret; + + if (ret != 0xaa) + goto err; + + ulpi->id.vendor = ulpi_read(ulpi, ULPI_VENDOR_ID_LOW); + ulpi->id.vendor |= ulpi_read(ulpi, ULPI_VENDOR_ID_HIGH) << 8; + + ulpi->id.product = ulpi_read(ulpi, ULPI_PRODUCT_ID_LOW); + ulpi->id.product |= ulpi_read(ulpi, ULPI_PRODUCT_ID_HIGH) << 8; + + /* Some ULPI devices don't have a vendor id so rely on OF match */ + if (ulpi->id.vendor == 0) + goto err; + + request_module("ulpi:v%04xp%04x", ulpi->id.vendor, ulpi->id.product); + return 0; +err: + of_device_request_module(&ulpi->dev); + return 0; +} + +static int ulpi_regs_show(struct seq_file *seq, void *data) +{ + struct ulpi *ulpi = seq->private; + +#define ulpi_print(name, reg) do { \ + int ret = ulpi_read(ulpi, reg); \ + if (ret < 0) \ + return ret; \ + seq_printf(seq, name " %.02x\n", ret); \ +} while (0) + + ulpi_print("Vendor ID Low ", ULPI_VENDOR_ID_LOW); + ulpi_print("Vendor ID High ", ULPI_VENDOR_ID_HIGH); + ulpi_print("Product ID Low ", ULPI_PRODUCT_ID_LOW); + ulpi_print("Product ID High ", ULPI_PRODUCT_ID_HIGH); + ulpi_print("Function Control ", ULPI_FUNC_CTRL); + ulpi_print("Interface Control ", ULPI_IFC_CTRL); + ulpi_print("OTG Control ", ULPI_OTG_CTRL); + ulpi_print("USB Interrupt Enable Rising ", ULPI_USB_INT_EN_RISE); + ulpi_print("USB Interrupt Enable Falling", ULPI_USB_INT_EN_FALL); + ulpi_print("USB Interrupt Status ", ULPI_USB_INT_STS); + ulpi_print("USB Interrupt Latch ", ULPI_USB_INT_LATCH); + ulpi_print("Debug ", ULPI_DEBUG); + ulpi_print("Scratch Register ", ULPI_SCRATCH); + ulpi_print("Carkit Control ", ULPI_CARKIT_CTRL); + ulpi_print("Carkit Interrupt Delay ", ULPI_CARKIT_INT_DELAY); + ulpi_print("Carkit Interrupt Enable ", ULPI_CARKIT_INT_EN); + ulpi_print("Carkit Interrupt Status ", ULPI_CARKIT_INT_STS); + ulpi_print("Carkit Interrupt Latch ", ULPI_CARKIT_INT_LATCH); + ulpi_print("Carkit Pulse Control ", ULPI_CARKIT_PLS_CTRL); + ulpi_print("Transmit Positive Width ", ULPI_TX_POS_WIDTH); + ulpi_print("Transmit Negative Width ", ULPI_TX_NEG_WIDTH); + ulpi_print("Receive Polarity Recovery ", ULPI_POLARITY_RECOVERY); + + return 0; +} +DEFINE_SHOW_ATTRIBUTE(ulpi_regs); + +static struct dentry *ulpi_root; + +static int ulpi_register(struct device *dev, struct ulpi *ulpi) +{ + int ret; + struct dentry *root; + + ulpi->dev.parent = dev; /* needed early for ops */ + ulpi->dev.bus = &ulpi_bus; + ulpi->dev.type = &ulpi_dev_type; + dev_set_name(&ulpi->dev, "%s.ulpi", dev_name(dev)); + + ACPI_COMPANION_SET(&ulpi->dev, ACPI_COMPANION(dev)); + + ret = ulpi_of_register(ulpi); + if (ret) + return ret; + + ret = ulpi_read_id(ulpi); + if (ret) { + of_node_put(ulpi->dev.of_node); + return ret; + } + + ret = device_register(&ulpi->dev); + if (ret) { + put_device(&ulpi->dev); + return ret; + } + + root = debugfs_create_dir(dev_name(dev), ulpi_root); + debugfs_create_file("regs", 0444, root, ulpi, &ulpi_regs_fops); + + dev_dbg(&ulpi->dev, "registered ULPI PHY: vendor %04x, product %04x\n", + ulpi->id.vendor, ulpi->id.product); + + return 0; +} + +/** + * ulpi_register_interface - instantiate new ULPI device + * @dev: USB controller's device interface + * @ops: ULPI register access + * + * Allocates and registers a ULPI device and an interface for it. Called from + * the USB controller that provides the ULPI interface. + */ +struct ulpi *ulpi_register_interface(struct device *dev, + const struct ulpi_ops *ops) +{ + struct ulpi *ulpi; + int ret; + + ulpi = kzalloc(sizeof(*ulpi), GFP_KERNEL); + if (!ulpi) + return ERR_PTR(-ENOMEM); + + ulpi->ops = ops; + + ret = ulpi_register(dev, ulpi); + if (ret) { + kfree(ulpi); + return ERR_PTR(ret); + } + + return ulpi; +} +EXPORT_SYMBOL_GPL(ulpi_register_interface); + +/** + * ulpi_unregister_interface - unregister ULPI interface + * @ulpi: struct ulpi_interface + * + * Unregisters a ULPI device and it's interface that was created with + * ulpi_create_interface(). + */ +void ulpi_unregister_interface(struct ulpi *ulpi) +{ + debugfs_lookup_and_remove(dev_name(&ulpi->dev), ulpi_root); + device_unregister(&ulpi->dev); +} +EXPORT_SYMBOL_GPL(ulpi_unregister_interface); + +/* -------------------------------------------------------------------------- */ + +static int __init ulpi_init(void) +{ + int ret; + + ulpi_root = debugfs_create_dir(KBUILD_MODNAME, NULL); + ret = bus_register(&ulpi_bus); + if (ret) + debugfs_remove(ulpi_root); + return ret; +} +subsys_initcall(ulpi_init); + +static void __exit ulpi_exit(void) +{ + bus_unregister(&ulpi_bus); + debugfs_remove(ulpi_root); +} +module_exit(ulpi_exit); + +MODULE_AUTHOR("Intel Corporation"); +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("USB ULPI PHY bus"); |