diff options
Diffstat (limited to 'drivers/usb/host/ehci-atmel.c')
-rw-r--r-- | drivers/usb/host/ehci-atmel.c | 249 |
1 files changed, 249 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c new file mode 100644 index 000000000..e893467d6 --- /dev/null +++ b/drivers/usb/host/ehci-atmel.c @@ -0,0 +1,249 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Driver for EHCI UHP on Atmel chips + * + * Copyright (C) 2009 Atmel Corporation, + * Nicolas Ferre <nicolas.ferre@atmel.com> + * + * Based on various ehci-*.c drivers + */ + +#include <linux/clk.h> +#include <linux/dma-mapping.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_platform.h> +#include <linux/platform_device.h> +#include <linux/usb.h> +#include <linux/usb/hcd.h> + +#include "ehci.h" + +#define DRIVER_DESC "EHCI Atmel driver" + +static const char hcd_name[] = "ehci-atmel"; + +/* interface and function clocks */ +#define hcd_to_atmel_ehci_priv(h) \ + ((struct atmel_ehci_priv *)hcd_to_ehci(h)->priv) + +struct atmel_ehci_priv { + struct clk *iclk; + struct clk *uclk; + bool clocked; +}; + +static struct hc_driver __read_mostly ehci_atmel_hc_driver; + +static const struct ehci_driver_overrides ehci_atmel_drv_overrides __initconst = { + .extra_priv_size = sizeof(struct atmel_ehci_priv), +}; + +/*-------------------------------------------------------------------------*/ + +static void atmel_start_clock(struct atmel_ehci_priv *atmel_ehci) +{ + if (atmel_ehci->clocked) + return; + + clk_prepare_enable(atmel_ehci->uclk); + clk_prepare_enable(atmel_ehci->iclk); + atmel_ehci->clocked = true; +} + +static void atmel_stop_clock(struct atmel_ehci_priv *atmel_ehci) +{ + if (!atmel_ehci->clocked) + return; + + clk_disable_unprepare(atmel_ehci->iclk); + clk_disable_unprepare(atmel_ehci->uclk); + atmel_ehci->clocked = false; +} + +static void atmel_start_ehci(struct platform_device *pdev) +{ + struct usb_hcd *hcd = platform_get_drvdata(pdev); + struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); + + dev_dbg(&pdev->dev, "start\n"); + atmel_start_clock(atmel_ehci); +} + +static void atmel_stop_ehci(struct platform_device *pdev) +{ + struct usb_hcd *hcd = platform_get_drvdata(pdev); + struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); + + dev_dbg(&pdev->dev, "stop\n"); + atmel_stop_clock(atmel_ehci); +} + +/*-------------------------------------------------------------------------*/ + +static int ehci_atmel_drv_probe(struct platform_device *pdev) +{ + struct usb_hcd *hcd; + const struct hc_driver *driver = &ehci_atmel_hc_driver; + struct resource *res; + struct ehci_hcd *ehci; + struct atmel_ehci_priv *atmel_ehci; + int irq; + int retval; + + if (usb_disabled()) + return -ENODEV; + + pr_debug("Initializing Atmel-SoC USB Host Controller\n"); + + irq = platform_get_irq(pdev, 0); + if (irq <= 0) { + retval = -ENODEV; + goto fail_create_hcd; + } + + /* Right now device-tree probed devices don't get dma_mask set. + * Since shared usb code relies on it, set it here for now. + * Once we have dma capability bindings this can go away. + */ + retval = dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32)); + if (retval) + goto fail_create_hcd; + + hcd = usb_create_hcd(driver, &pdev->dev, dev_name(&pdev->dev)); + if (!hcd) { + retval = -ENOMEM; + goto fail_create_hcd; + } + atmel_ehci = hcd_to_atmel_ehci_priv(hcd); + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + hcd->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hcd->regs)) { + retval = PTR_ERR(hcd->regs); + goto fail_request_resource; + } + + hcd->rsrc_start = res->start; + hcd->rsrc_len = resource_size(res); + + atmel_ehci->iclk = devm_clk_get(&pdev->dev, "ehci_clk"); + if (IS_ERR(atmel_ehci->iclk)) { + dev_err(&pdev->dev, "Error getting interface clock\n"); + retval = -ENOENT; + goto fail_request_resource; + } + + atmel_ehci->uclk = devm_clk_get(&pdev->dev, "usb_clk"); + if (IS_ERR(atmel_ehci->uclk)) { + dev_err(&pdev->dev, "failed to get uclk\n"); + retval = PTR_ERR(atmel_ehci->uclk); + goto fail_request_resource; + } + + ehci = hcd_to_ehci(hcd); + /* registers start at offset 0x0 */ + ehci->caps = hcd->regs; + + atmel_start_ehci(pdev); + + retval = usb_add_hcd(hcd, irq, IRQF_SHARED); + if (retval) + goto fail_add_hcd; + device_wakeup_enable(hcd->self.controller); + + return retval; + +fail_add_hcd: + atmel_stop_ehci(pdev); +fail_request_resource: + usb_put_hcd(hcd); +fail_create_hcd: + dev_err(&pdev->dev, "init %s fail, %d\n", + dev_name(&pdev->dev), retval); + + return retval; +} + +static int ehci_atmel_drv_remove(struct platform_device *pdev) +{ + struct usb_hcd *hcd = platform_get_drvdata(pdev); + + usb_remove_hcd(hcd); + usb_put_hcd(hcd); + + atmel_stop_ehci(pdev); + + return 0; +} + +static int __maybe_unused ehci_atmel_drv_suspend(struct device *dev) +{ + struct usb_hcd *hcd = dev_get_drvdata(dev); + struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); + int ret; + + ret = ehci_suspend(hcd, false); + if (ret) + return ret; + + atmel_stop_clock(atmel_ehci); + return 0; +} + +static int __maybe_unused ehci_atmel_drv_resume(struct device *dev) +{ + struct usb_hcd *hcd = dev_get_drvdata(dev); + struct atmel_ehci_priv *atmel_ehci = hcd_to_atmel_ehci_priv(hcd); + + atmel_start_clock(atmel_ehci); + ehci_resume(hcd, false); + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id atmel_ehci_dt_ids[] = { + { .compatible = "atmel,at91sam9g45-ehci" }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, atmel_ehci_dt_ids); +#endif + +static SIMPLE_DEV_PM_OPS(ehci_atmel_pm_ops, ehci_atmel_drv_suspend, + ehci_atmel_drv_resume); + +static struct platform_driver ehci_atmel_driver = { + .probe = ehci_atmel_drv_probe, + .remove = ehci_atmel_drv_remove, + .shutdown = usb_hcd_platform_shutdown, + .driver = { + .name = "atmel-ehci", + .pm = &ehci_atmel_pm_ops, + .of_match_table = of_match_ptr(atmel_ehci_dt_ids), + }, +}; + +static int __init ehci_atmel_init(void) +{ + if (usb_disabled()) + return -ENODEV; + + pr_info("%s: " DRIVER_DESC "\n", hcd_name); + ehci_init_driver(&ehci_atmel_hc_driver, &ehci_atmel_drv_overrides); + return platform_driver_register(&ehci_atmel_driver); +} +module_init(ehci_atmel_init); + +static void __exit ehci_atmel_cleanup(void) +{ + platform_driver_unregister(&ehci_atmel_driver); +} +module_exit(ehci_atmel_cleanup); + +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_ALIAS("platform:atmel-ehci"); +MODULE_AUTHOR("Nicolas Ferre"); +MODULE_LICENSE("GPL"); |