diff options
Diffstat (limited to 'drivers/usb/host/ehci-atmel.c')
| -rw-r--r-- | drivers/usb/host/ehci-atmel.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-atmel.c b/drivers/usb/host/ehci-atmel.c new file mode 100644 index 00000000000..ec9f7b75d49 --- /dev/null +++ b/drivers/usb/host/ehci-atmel.c @@ -0,0 +1,223 @@ +/* + * Driver for EHCI UHP on Atmel chips + * + * Copyright (C) 2009 Atmel Corporation, + * Nicolas Ferre <nicolas.ferre@atmel.com> + * + * Based on various ehci-*.c drivers + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive for + * more details. + */ + +#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"; +static struct hc_driver __read_mostly ehci_atmel_hc_driver; + +/* interface and function clocks */ +static struct clk *iclk, *fclk, *uclk; +static int clocked; + +/*-------------------------------------------------------------------------*/ + +static void atmel_start_clock(void) +{ + if (IS_ENABLED(CONFIG_COMMON_CLK)) { + clk_set_rate(uclk, 48000000); + clk_prepare_enable(uclk); + } + clk_prepare_enable(iclk); + clk_prepare_enable(fclk); + clocked = 1; +} + +static void atmel_stop_clock(void) +{ + clk_disable_unprepare(fclk); + clk_disable_unprepare(iclk); + if (IS_ENABLED(CONFIG_COMMON_CLK)) + clk_disable_unprepare(uclk); + clocked = 0; +} + +static void atmel_start_ehci(struct platform_device *pdev) +{ + dev_dbg(&pdev->dev, "start\n"); + atmel_start_clock(); +} + +static void atmel_stop_ehci(struct platform_device *pdev) +{ + dev_dbg(&pdev->dev, "stop\n"); + atmel_stop_clock(); +} + +/*-------------------------------------------------------------------------*/ + +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; + 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) { + dev_err(&pdev->dev, + "Found HC with no IRQ. Check %s setup!\n", + dev_name(&pdev->dev)); + 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; + } + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, + "Found HC with no register addr. Check %s setup!\n", + dev_name(&pdev->dev)); + retval = -ENODEV; + goto fail_request_resource; + } + hcd->rsrc_start = res->start; + hcd->rsrc_len = resource_size(res); + + hcd->regs = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(hcd->regs)) { + retval = PTR_ERR(hcd->regs); + goto fail_request_resource; + } + + iclk = devm_clk_get(&pdev->dev, "ehci_clk"); + if (IS_ERR(iclk)) { + dev_err(&pdev->dev, "Error getting interface clock\n"); + retval = -ENOENT; + goto fail_request_resource; + } + fclk = devm_clk_get(&pdev->dev, "uhpck"); + if (IS_ERR(fclk)) { + dev_err(&pdev->dev, "Error getting function clock\n"); + retval = -ENOENT; + goto fail_request_resource; + } + if (IS_ENABLED(CONFIG_COMMON_CLK)) { + uclk = devm_clk_get(&pdev->dev, "usb_clk"); + if (IS_ERR(uclk)) { + dev_err(&pdev->dev, "failed to get uclk\n"); + retval = PTR_ERR(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); + fclk = iclk = NULL; + + 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 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", + .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, NULL); + 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"); |