diff options
Diffstat (limited to 'drivers/usb/phy/nop-usb-xceiv.c')
| -rw-r--r-- | drivers/usb/phy/nop-usb-xceiv.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/drivers/usb/phy/nop-usb-xceiv.c b/drivers/usb/phy/nop-usb-xceiv.c new file mode 100644 index 0000000..2b10cc9 --- /dev/null +++ b/drivers/usb/phy/nop-usb-xceiv.c @@ -0,0 +1,294 @@ +/* + * drivers/usb/otg/nop-usb-xceiv.c + * + * NOP USB transceiver for all USB transceiver which are either built-in + * into USB IP or which are mostly autonomous. + * + * Copyright (C) 2009 Texas Instruments Inc + * Author: Ajay Kumar Gupta <ajay.gupta@ti.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * + * Current status: + * This provides a "nop" transceiver for PHYs which are + * autonomous such as isp1504, isp1707, etc. + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/dma-mapping.h> +#include <linux/usb/otg.h> +#include <linux/usb/nop-usb-xceiv.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/regulator/consumer.h> +#include <linux/of.h> + +struct nop_usb_xceiv { + struct usb_phy phy; + struct device *dev; + struct clk *clk; + struct regulator *vcc; + struct regulator *reset; +}; + +static struct platform_device *pd; + +void usb_nop_xceiv_register(void) +{ + if (pd) + return; + pd = platform_device_register_simple("nop_usb_xceiv", -1, NULL, 0); + if (!pd) { + printk(KERN_ERR "Unable to register usb nop transceiver\n"); + return; + } +} +EXPORT_SYMBOL(usb_nop_xceiv_register); + +void usb_nop_xceiv_unregister(void) +{ + platform_device_unregister(pd); + pd = NULL; +} +EXPORT_SYMBOL(usb_nop_xceiv_unregister); + +static int nop_set_suspend(struct usb_phy *x, int suspend) +{ + return 0; +} + +static int nop_init(struct usb_phy *phy) +{ + struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev); + + if (!IS_ERR(nop->vcc)) { + if (regulator_enable(nop->vcc)) + dev_err(phy->dev, "Failed to enable power\n"); + } + + if (!IS_ERR(nop->clk)) + clk_enable(nop->clk); + + if (!IS_ERR(nop->reset)) { + /* De-assert RESET */ + if (regulator_enable(nop->reset)) + dev_err(phy->dev, "Failed to de-assert reset\n"); + } + + return 0; +} + +static void nop_shutdown(struct usb_phy *phy) +{ + struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev); + + if (!IS_ERR(nop->reset)) { + /* Assert RESET */ + if (regulator_disable(nop->reset)) + dev_err(phy->dev, "Failed to assert reset\n"); + } + + if (!IS_ERR(nop->clk)) + clk_disable(nop->clk); + + if (!IS_ERR(nop->vcc)) { + if (regulator_disable(nop->vcc)) + dev_err(phy->dev, "Failed to disable power\n"); + } +} + +static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget) +{ + if (!otg) + return -ENODEV; + + if (!gadget) { + otg->gadget = NULL; + return -ENODEV; + } + + otg->gadget = gadget; + otg->phy->state = OTG_STATE_B_IDLE; + return 0; +} + +static int nop_set_host(struct usb_otg *otg, struct usb_bus *host) +{ + if (!otg) + return -ENODEV; + + if (!host) { + otg->host = NULL; + return -ENODEV; + } + + otg->host = host; + return 0; +} + +static int nop_usb_xceiv_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct nop_usb_xceiv_platform_data *pdata = pdev->dev.platform_data; + struct nop_usb_xceiv *nop; + enum usb_phy_type type = USB_PHY_TYPE_USB2; + int err; + u32 clk_rate = 0; + bool needs_vcc = false; + bool needs_reset = false; + + nop = devm_kzalloc(&pdev->dev, sizeof(*nop), GFP_KERNEL); + if (!nop) + return -ENOMEM; + + nop->phy.otg = devm_kzalloc(&pdev->dev, sizeof(*nop->phy.otg), + GFP_KERNEL); + if (!nop->phy.otg) + return -ENOMEM; + + if (dev->of_node) { + struct device_node *node = dev->of_node; + + if (of_property_read_u32(node, "clock-frequency", &clk_rate)) + clk_rate = 0; + + needs_vcc = of_property_read_bool(node, "vcc-supply"); + needs_reset = of_property_read_bool(node, "reset-supply"); + + } else if (pdata) { + type = pdata->type; + clk_rate = pdata->clk_rate; + needs_vcc = pdata->needs_vcc; + needs_reset = pdata->needs_reset; + } + + nop->clk = devm_clk_get(&pdev->dev, "main_clk"); + if (IS_ERR(nop->clk)) { + dev_dbg(&pdev->dev, "Can't get phy clock: %ld\n", + PTR_ERR(nop->clk)); + } + + if (!IS_ERR(nop->clk) && clk_rate) { + err = clk_set_rate(nop->clk, clk_rate); + if (err) { + dev_err(&pdev->dev, "Error setting clock rate\n"); + return err; + } + } + + if (!IS_ERR(nop->clk)) { + err = clk_prepare(nop->clk); + if (err) { + dev_err(&pdev->dev, "Error preparing clock\n"); + return err; + } + } + + nop->vcc = devm_regulator_get(&pdev->dev, "vcc"); + if (IS_ERR(nop->vcc)) { + dev_dbg(&pdev->dev, "Error getting vcc regulator: %ld\n", + PTR_ERR(nop->vcc)); + if (needs_vcc) + return -EPROBE_DEFER; + } + + nop->reset = devm_regulator_get(&pdev->dev, "reset"); + if (IS_ERR(nop->reset)) { + dev_dbg(&pdev->dev, "Error getting reset regulator: %ld\n", + PTR_ERR(nop->reset)); + if (needs_reset) + return -EPROBE_DEFER; + } + + nop->dev = &pdev->dev; + nop->phy.dev = nop->dev; + nop->phy.label = "nop-xceiv"; + nop->phy.set_suspend = nop_set_suspend; + nop->phy.init = nop_init; + nop->phy.shutdown = nop_shutdown; + nop->phy.state = OTG_STATE_UNDEFINED; + nop->phy.type = type; + + nop->phy.otg->phy = &nop->phy; + nop->phy.otg->set_host = nop_set_host; + nop->phy.otg->set_peripheral = nop_set_peripheral; + + err = usb_add_phy_dev(&nop->phy); + if (err) { + dev_err(&pdev->dev, "can't register transceiver, err: %d\n", + err); + goto err_add; + } + + platform_set_drvdata(pdev, nop); + + ATOMIC_INIT_NOTIFIER_HEAD(&nop->phy.notifier); + + return 0; + +err_add: + if (!IS_ERR(nop->clk)) + clk_unprepare(nop->clk); + return err; +} + +static int nop_usb_xceiv_remove(struct platform_device *pdev) +{ + struct nop_usb_xceiv *nop = platform_get_drvdata(pdev); + + if (!IS_ERR(nop->clk)) + clk_unprepare(nop->clk); + + usb_remove_phy(&nop->phy); + + platform_set_drvdata(pdev, NULL); + + return 0; +} + +static const struct of_device_id nop_xceiv_dt_ids[] = { + { .compatible = "usb-nop-xceiv" }, + { } +}; + +MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids); + +static struct platform_driver nop_usb_xceiv_driver = { + .probe = nop_usb_xceiv_probe, + .remove = nop_usb_xceiv_remove, + .driver = { + .name = "nop_usb_xceiv", + .owner = THIS_MODULE, + .of_match_table = of_match_ptr(nop_xceiv_dt_ids), + }, +}; + +static int __init nop_usb_xceiv_init(void) +{ + return platform_driver_register(&nop_usb_xceiv_driver); +} +subsys_initcall(nop_usb_xceiv_init); + +static void __exit nop_usb_xceiv_exit(void) +{ + platform_driver_unregister(&nop_usb_xceiv_driver); +} +module_exit(nop_usb_xceiv_exit); + +MODULE_ALIAS("platform:nop_usb_xceiv"); +MODULE_AUTHOR("Texas Instruments Inc"); +MODULE_DESCRIPTION("NOP USB Transceiver driver"); +MODULE_LICENSE("GPL"); |