From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Griffin Subject: [PATCH v6 1/5] usb: host: ehci-st: Add EHCI support for ST STB devices Date: Mon, 8 Sep 2014 13:04:44 +0100 Message-ID: <1410177888-26710-2-git-send-email-peter.griffin@linaro.org> References: <1410177888-26710-1-git-send-email-peter.griffin@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1410177888-26710-1-git-send-email-peter.griffin@linaro.org> Sender: linux-kernel-owner@vger.kernel.org To: linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, stern@rowland.harvard.edu, gregkh@linuxfoundation.org, srinivas.kandagatla@gmail.com, maxime.coquelin@st.com, patrice.chotard@st.com, arnd@arndb.de Cc: peter.griffin@linaro.org, lee.jones@linaro.org, devicetree@vger.kernel.org, linux-usb@vger.kernel.org List-Id: devicetree@vger.kernel.org This patch adds the glue code required to ensure the on-chip EHCI controller works on STi consumer electronics SoC's from STMicroelectron= ics. It mainly manages the setting and enabling of the relevant clocks and m= anages the reset / power signals to the IP block. Signed-off-by: Peter Griffin --- drivers/usb/host/ehci-st.c | 375 +++++++++++++++++++++++++++++++++++++= ++++++++ 1 file changed, 375 insertions(+) create mode 100644 drivers/usb/host/ehci-st.c diff --git a/drivers/usb/host/ehci-st.c b/drivers/usb/host/ehci-st.c new file mode 100644 index 0000000..7e4bd39 --- /dev/null +++ b/drivers/usb/host/ehci-st.c @@ -0,0 +1,375 @@ +/* + * ST EHCI driver + * + * Copyright (C) 2014 STMicroelectronics =E2=80=93 All Rights Reserved + * + * Author: Peter Griffin + * + * Derived from ehci-platform.c + * + * This program is free software; you can redistribute it and/or modif= y + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "ehci.h" + +#define USB_MAX_CLKS 3 + +struct st_ehci_platform_priv { + struct clk *clks[USB_MAX_CLKS]; + struct clk *clk48; + struct reset_control *rst; + struct reset_control *pwr; + struct phy *phy; +}; + +#define DRIVER_DESC "EHCI STMicroelectronics driver" + +#define hcd_to_ehci_priv(h) \ + ((struct st_ehci_platform_priv *)hcd_to_ehci(h)->priv) + +static const char hcd_name[] =3D "ehci-st"; + +#define EHCI_CAPS_SIZE 0x10 +#define AHB2STBUS_INSREG01 (EHCI_CAPS_SIZE + 0x84) + +static int st_ehci_platform_reset(struct usb_hcd *hcd) +{ + struct platform_device *pdev =3D to_platform_device(hcd->self.control= ler); + struct usb_ehci_pdata *pdata =3D dev_get_platdata(&pdev->dev); + struct ehci_hcd *ehci =3D hcd_to_ehci(hcd); + int retval; + u32 threshold; + + /* Set EHCI packet buffer IN/OUT threshold to 128 bytes */ + threshold =3D 128 | (128 << 16); + writel(threshold, hcd->regs + AHB2STBUS_INSREG01); + + ehci->caps =3D hcd->regs + pdata->caps_offset; + retval =3D ehci_setup(hcd); + if (retval) + return retval; + + return 0; +} + +static int st_ehci_platform_power_on(struct platform_device *dev) +{ + struct usb_hcd *hcd =3D platform_get_drvdata(dev); + struct st_ehci_platform_priv *priv =3D hcd_to_ehci_priv(hcd); + int clk, ret; + + ret =3D reset_control_deassert(priv->pwr); + if (ret) + return ret; + + ret =3D reset_control_deassert(priv->rst); + if (ret) + goto err_assert_power; + + /* some SoCs don't have a dedicated 48Mhz clock, but those that do + need the rate to be explicitly set */ + if (priv->clk48) { + ret =3D clk_set_rate(priv->clk48, 48000000); + if (ret) + goto err_assert_reset; + } + + for (clk =3D 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) { + ret =3D clk_prepare_enable(priv->clks[clk]); + if (ret) + goto err_disable_clks; + } + + ret =3D phy_init(priv->phy); + if (ret) + goto err_disable_clks; + + ret =3D phy_power_on(priv->phy); + if (ret) + goto err_exit_phy; + + return 0; + +err_exit_phy: + phy_exit(priv->phy); +err_disable_clks: + while (--clk >=3D 0) + clk_disable_unprepare(priv->clks[clk]); +err_assert_reset: + reset_control_assert(priv->rst); +err_assert_power: + reset_control_assert(priv->pwr); + + return ret; +} + +static void st_ehci_platform_power_off(struct platform_device *dev) +{ + struct usb_hcd *hcd =3D platform_get_drvdata(dev); + struct st_ehci_platform_priv *priv =3D hcd_to_ehci_priv(hcd); + int clk; + + reset_control_assert(priv->pwr); + + reset_control_assert(priv->rst); + + phy_power_off(priv->phy); + + phy_exit(priv->phy); + + for (clk =3D USB_MAX_CLKS - 1; clk >=3D 0; clk--) + if (priv->clks[clk]) + clk_disable_unprepare(priv->clks[clk]); + +} + +static struct hc_driver __read_mostly ehci_platform_hc_driver; + +static const struct ehci_driver_overrides platform_overrides __initcon= st =3D { + .reset =3D st_ehci_platform_reset, + .extra_priv_size =3D sizeof(struct st_ehci_platform_priv), +}; + +static struct usb_ehci_pdata ehci_platform_defaults =3D { + .power_on =3D st_ehci_platform_power_on, + .power_suspend =3D st_ehci_platform_power_off, + .power_off =3D st_ehci_platform_power_off, +}; + +static int st_ehci_platform_probe(struct platform_device *dev) +{ + struct usb_hcd *hcd; + struct resource *res_mem; + struct usb_ehci_pdata *pdata =3D &ehci_platform_defaults; + struct st_ehci_platform_priv *priv; + struct ehci_hcd *ehci; + int err, irq, clk =3D 0; + + if (usb_disabled()) + return -ENODEV; + + irq =3D platform_get_irq(dev, 0); + if (irq < 0) { + dev_err(&dev->dev, "no irq provided"); + return irq; + } + res_mem =3D platform_get_resource(dev, IORESOURCE_MEM, 0); + if (!res_mem) { + dev_err(&dev->dev, "no memory resource provided"); + return -ENXIO; + } + + hcd =3D usb_create_hcd(&ehci_platform_hc_driver, &dev->dev, + dev_name(&dev->dev)); + if (!hcd) + return -ENOMEM; + + platform_set_drvdata(dev, hcd); + dev->dev.platform_data =3D pdata; + priv =3D hcd_to_ehci_priv(hcd); + ehci =3D hcd_to_ehci(hcd); + + priv->phy =3D devm_phy_get(&dev->dev, "usb"); + if (IS_ERR(priv->phy)) { + err =3D PTR_ERR(priv->phy); + goto err_put_hcd; + } + + for (clk =3D 0; clk < USB_MAX_CLKS; clk++) { + priv->clks[clk] =3D of_clk_get(dev->dev.of_node, clk); + if (IS_ERR(priv->clks[clk])) { + err =3D PTR_ERR(priv->clks[clk]); + if (err =3D=3D -EPROBE_DEFER) + goto err_put_clks; + priv->clks[clk] =3D NULL; + break; + } + } + + /* some SoCs don't have a dedicated 48Mhz clock, but those that + do need the rate to be explicitly set */ + priv->clk48 =3D devm_clk_get(&dev->dev, "clk48"); + if (IS_ERR(priv->clk48)) { + dev_info(&dev->dev, "48MHz clk not found\n"); + priv->clk48 =3D NULL; + } + + priv->pwr =3D devm_reset_control_get_optional(&dev->dev, "power"); + if (IS_ERR(priv->pwr)) { + err =3D PTR_ERR(priv->pwr); + if (err =3D=3D -EPROBE_DEFER) + goto err_put_clks; + priv->pwr =3D NULL; + } + + priv->rst =3D devm_reset_control_get_optional(&dev->dev, "softreset")= ; + if (IS_ERR(priv->rst)) { + err =3D PTR_ERR(priv->rst); + if (err =3D=3D -EPROBE_DEFER) + goto err_put_clks; + priv->rst =3D NULL; + } + + if (pdata->power_on) { + err =3D pdata->power_on(dev); + if (err < 0) + goto err_put_clks; + } + + hcd->rsrc_start =3D res_mem->start; + hcd->rsrc_len =3D resource_size(res_mem); + + hcd->regs =3D devm_ioremap_resource(&dev->dev, res_mem); + if (IS_ERR(hcd->regs)) { + err =3D PTR_ERR(hcd->regs); + goto err_put_clks; + } + + err =3D usb_add_hcd(hcd, irq, IRQF_SHARED); + if (err) + goto err_put_clks; + + device_wakeup_enable(hcd->self.controller); + platform_set_drvdata(dev, hcd); + + return err; + +err_put_clks: + while (--clk >=3D 0) + clk_put(priv->clks[clk]); +err_put_hcd: + if (pdata =3D=3D &ehci_platform_defaults) + dev->dev.platform_data =3D NULL; + + usb_put_hcd(hcd); + + return err; +} + +static int st_ehci_platform_remove(struct platform_device *dev) +{ + struct usb_hcd *hcd =3D platform_get_drvdata(dev); + struct usb_ehci_pdata *pdata =3D dev_get_platdata(&dev->dev); + struct st_ehci_platform_priv *priv =3D hcd_to_ehci_priv(hcd); + int clk; + + usb_remove_hcd(hcd); + + if (pdata->power_off) + pdata->power_off(dev); + + for (clk =3D 0; clk < USB_MAX_CLKS && priv->clks[clk]; clk++) + clk_put(priv->clks[clk]); + + usb_put_hcd(hcd); + + if (pdata =3D=3D &ehci_platform_defaults) + dev->dev.platform_data =3D NULL; + + return 0; +} + +#ifdef CONFIG_PM_SLEEP + +static int st_ehci_suspend(struct device *dev) +{ + struct usb_hcd *hcd =3D dev_get_drvdata(dev); + struct usb_ehci_pdata *pdata =3D dev_get_platdata(dev); + struct platform_device *pdev =3D + container_of(dev, struct platform_device, dev); + bool do_wakeup =3D device_may_wakeup(dev); + int ret; + + ret =3D ehci_suspend(hcd, do_wakeup); + if (ret) + return ret; + + if (pdata->power_suspend) + pdata->power_suspend(pdev); + + pinctrl_pm_select_sleep_state(dev); + + return ret; +} + +static int st_ehci_resume(struct device *dev) +{ + struct usb_hcd *hcd =3D dev_get_drvdata(dev); + struct usb_ehci_pdata *pdata =3D dev_get_platdata(dev); + struct platform_device *pdev =3D + container_of(dev, struct platform_device, dev); + int err; + + pinctrl_pm_select_default_state(dev); + + if (pdata->power_on) { + err =3D pdata->power_on(pdev); + if (err < 0) + return err; + } + + ehci_resume(hcd, false); + return 0; +} + +static SIMPLE_DEV_PM_OPS(st_ehci_pm_ops, st_ehci_suspend, st_ehci_resu= me); + +#endif /* CONFIG_PM_SLEEP */ + +static const struct of_device_id st_ehci_ids[] =3D { + { .compatible =3D "st,st-ehci-300x", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, st_ehci_ids); + +static struct platform_driver ehci_platform_driver =3D { + .probe =3D st_ehci_platform_probe, + .remove =3D st_ehci_platform_remove, + .shutdown =3D usb_hcd_platform_shutdown, + .driver =3D { + .name =3D "st-ehci", +#ifdef CONFIG_PM_SLEEP + .pm =3D &st_ehci_pm_ops, +#endif + .of_match_table =3D st_ehci_ids, + } +}; + +static int __init ehci_platform_init(void) +{ + if (usb_disabled()) + return -ENODEV; + + pr_info("%s: " DRIVER_DESC "\n", hcd_name); + + ehci_init_driver(&ehci_platform_hc_driver, &platform_overrides); + return platform_driver_register(&ehci_platform_driver); +} +module_init(ehci_platform_init); + +static void __exit ehci_platform_cleanup(void) +{ + platform_driver_unregister(&ehci_platform_driver); +} +module_exit(ehci_platform_cleanup); + +MODULE_DESCRIPTION(DRIVER_DESC); +MODULE_AUTHOR("Peter Griffin "); +MODULE_LICENSE("GPL"); --=20 1.9.1