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path: root/drivers/usb/phy/phy-samsung-usb3.c
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Diffstat (limited to 'drivers/usb/phy/phy-samsung-usb3.c')
-rw-r--r--drivers/usb/phy/phy-samsung-usb3.c347
1 files changed, 347 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-samsung-usb3.c b/drivers/usb/phy/phy-samsung-usb3.c
new file mode 100644
index 000000000000..133f3d0c554f
--- /dev/null
+++ b/drivers/usb/phy/phy-samsung-usb3.c
@@ -0,0 +1,347 @@
+/* linux/drivers/usb/phy/phy-samsung-usb3.c
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ * http://www.samsung.com
+ *
+ * Author: Vivek Gautam <gautam.vivek@samsung.com>
+ *
+ * Samsung USB 3.0 PHY transceiver; talks to DWC3 controller.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/usb/samsung_usb_phy.h>
+#include <linux/platform_data/samsung-usbphy.h>
+
+#include "phy-samsung-usb.h"
+
+/*
+ * Sets the phy clk as EXTREFCLK (XXTI) which is internal clock from clock core.
+ */
+static u32 samsung_usb3phy_set_refclk(struct samsung_usbphy *sphy)
+{
+ u32 reg;
+ u32 refclk;
+
+ refclk = sphy->ref_clk_freq;
+
+ reg = PHYCLKRST_REFCLKSEL_EXT_REFCLK |
+ PHYCLKRST_FSEL(refclk);
+
+ switch (refclk) {
+ case FSEL_CLKSEL_50M:
+ reg |= (PHYCLKRST_MPLL_MULTIPLIER_50M_REF |
+ PHYCLKRST_SSC_REFCLKSEL(0x00));
+ break;
+ case FSEL_CLKSEL_20M:
+ reg |= (PHYCLKRST_MPLL_MULTIPLIER_20MHZ_REF |
+ PHYCLKRST_SSC_REFCLKSEL(0x00));
+ break;
+ case FSEL_CLKSEL_19200K:
+ reg |= (PHYCLKRST_MPLL_MULTIPLIER_19200KHZ_REF |
+ PHYCLKRST_SSC_REFCLKSEL(0x88));
+ break;
+ case FSEL_CLKSEL_24M:
+ default:
+ reg |= (PHYCLKRST_MPLL_MULTIPLIER_24MHZ_REF |
+ PHYCLKRST_SSC_REFCLKSEL(0x88));
+ break;
+ }
+
+ return reg;
+}
+
+static int samsung_exynos5_usb3phy_enable(struct samsung_usbphy *sphy)
+{
+ void __iomem *regs = sphy->regs;
+ u32 phyparam0;
+ u32 phyparam1;
+ u32 linksystem;
+ u32 phybatchg;
+ u32 phytest;
+ u32 phyclkrst;
+
+ /* Reset USB 3.0 PHY */
+ writel(0x0, regs + EXYNOS5_DRD_PHYREG0);
+
+ phyparam0 = readl(regs + EXYNOS5_DRD_PHYPARAM0);
+ /* Select PHY CLK source */
+ phyparam0 &= ~PHYPARAM0_REF_USE_PAD;
+ /* Set Loss-of-Signal Detector sensitivity */
+ phyparam0 &= ~PHYPARAM0_REF_LOSLEVEL_MASK;
+ phyparam0 |= PHYPARAM0_REF_LOSLEVEL;
+ writel(phyparam0, regs + EXYNOS5_DRD_PHYPARAM0);
+
+ writel(0x0, regs + EXYNOS5_DRD_PHYRESUME);
+
+ /*
+ * Setting the Frame length Adj value[6:1] to default 0x20
+ * See xHCI 1.0 spec, 5.2.4
+ */
+ linksystem = LINKSYSTEM_XHCI_VERSION_CONTROL |
+ LINKSYSTEM_FLADJ(0x20);
+ writel(linksystem, regs + EXYNOS5_DRD_LINKSYSTEM);
+
+ phyparam1 = readl(regs + EXYNOS5_DRD_PHYPARAM1);
+ /* Set Tx De-Emphasis level */
+ phyparam1 &= ~PHYPARAM1_PCS_TXDEEMPH_MASK;
+ phyparam1 |= PHYPARAM1_PCS_TXDEEMPH;
+ writel(phyparam1, regs + EXYNOS5_DRD_PHYPARAM1);
+
+ phybatchg = readl(regs + EXYNOS5_DRD_PHYBATCHG);
+ phybatchg |= PHYBATCHG_UTMI_CLKSEL;
+ writel(phybatchg, regs + EXYNOS5_DRD_PHYBATCHG);
+
+ /* PHYTEST POWERDOWN Control */
+ phytest = readl(regs + EXYNOS5_DRD_PHYTEST);
+ phytest &= ~(PHYTEST_POWERDOWN_SSP |
+ PHYTEST_POWERDOWN_HSP);
+ writel(phytest, regs + EXYNOS5_DRD_PHYTEST);
+
+ /* UTMI Power Control */
+ writel(PHYUTMI_OTGDISABLE, regs + EXYNOS5_DRD_PHYUTMI);
+
+ phyclkrst = samsung_usb3phy_set_refclk(sphy);
+
+ phyclkrst |= PHYCLKRST_PORTRESET |
+ /* Digital power supply in normal operating mode */
+ PHYCLKRST_RETENABLEN |
+ /* Enable ref clock for SS function */
+ PHYCLKRST_REF_SSP_EN |
+ /* Enable spread spectrum */
+ PHYCLKRST_SSC_EN |
+ /* Power down HS Bias and PLL blocks in suspend mode */
+ PHYCLKRST_COMMONONN;
+
+ writel(phyclkrst, regs + EXYNOS5_DRD_PHYCLKRST);
+
+ udelay(10);
+
+ phyclkrst &= ~(PHYCLKRST_PORTRESET);
+ writel(phyclkrst, regs + EXYNOS5_DRD_PHYCLKRST);
+
+ return 0;
+}
+
+static void samsung_exynos5_usb3phy_disable(struct samsung_usbphy *sphy)
+{
+ u32 phyutmi;
+ u32 phyclkrst;
+ u32 phytest;
+ void __iomem *regs = sphy->regs;
+
+ phyutmi = PHYUTMI_OTGDISABLE |
+ PHYUTMI_FORCESUSPEND |
+ PHYUTMI_FORCESLEEP;
+ writel(phyutmi, regs + EXYNOS5_DRD_PHYUTMI);
+
+ /* Resetting the PHYCLKRST enable bits to reduce leakage current */
+ phyclkrst = readl(regs + EXYNOS5_DRD_PHYCLKRST);
+ phyclkrst &= ~(PHYCLKRST_REF_SSP_EN |
+ PHYCLKRST_SSC_EN |
+ PHYCLKRST_COMMONONN);
+ writel(phyclkrst, regs + EXYNOS5_DRD_PHYCLKRST);
+
+ /* Control PHYTEST to remove leakage current */
+ phytest = readl(regs + EXYNOS5_DRD_PHYTEST);
+ phytest |= (PHYTEST_POWERDOWN_SSP |
+ PHYTEST_POWERDOWN_HSP);
+ writel(phytest, regs + EXYNOS5_DRD_PHYTEST);
+}
+
+static int samsung_usb3phy_init(struct usb_phy *phy)
+{
+ struct samsung_usbphy *sphy;
+ unsigned long flags;
+ int ret = 0;
+
+ sphy = phy_to_sphy(phy);
+
+ /* Enable the phy clock */
+ ret = clk_prepare_enable(sphy->clk);
+ if (ret) {
+ dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
+ return ret;
+ }
+
+ spin_lock_irqsave(&sphy->lock, flags);
+
+ /* setting default phy-type for USB 3.0 */
+ samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_DEVICE);
+
+ /* Disable phy isolation */
+ samsung_usbphy_set_isolation(sphy, false);
+
+ /* Initialize usb phy registers */
+ samsung_exynos5_usb3phy_enable(sphy);
+
+ spin_unlock_irqrestore(&sphy->lock, flags);
+
+ /* Disable the phy clock */
+ clk_disable_unprepare(sphy->clk);
+
+ return ret;
+}
+
+/*
+ * The function passed to the usb driver for phy shutdown
+ */
+static void samsung_usb3phy_shutdown(struct usb_phy *phy)
+{
+ struct samsung_usbphy *sphy;
+ unsigned long flags;
+
+ sphy = phy_to_sphy(phy);
+
+ if (clk_prepare_enable(sphy->clk)) {
+ dev_err(sphy->dev, "%s: clk_prepare_enable failed\n", __func__);
+ return;
+ }
+
+ spin_lock_irqsave(&sphy->lock, flags);
+
+ /* setting default phy-type for USB 3.0 */
+ samsung_usbphy_set_type(&sphy->phy, USB_PHY_TYPE_DEVICE);
+
+ /* De-initialize usb phy registers */
+ samsung_exynos5_usb3phy_disable(sphy);
+
+ /* Enable phy isolation */
+ samsung_usbphy_set_isolation(sphy, true);
+
+ spin_unlock_irqrestore(&sphy->lock, flags);
+
+ clk_disable_unprepare(sphy->clk);
+}
+
+static int samsung_usb3phy_probe(struct platform_device *pdev)
+{
+ struct samsung_usbphy *sphy;
+ struct samsung_usbphy_data *pdata = pdev->dev.platform_data;
+ struct device *dev = &pdev->dev;
+ struct resource *phy_mem;
+ void __iomem *phy_base;
+ struct clk *clk;
+ int ret;
+
+ phy_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!phy_mem) {
+ dev_err(dev, "%s: missing mem resource\n", __func__);
+ return -ENODEV;
+ }
+
+ phy_base = devm_ioremap_resource(dev, phy_mem);
+ if (IS_ERR(phy_base))
+ return PTR_ERR(phy_base);
+
+ sphy = devm_kzalloc(dev, sizeof(*sphy), GFP_KERNEL);
+ if (!sphy)
+ return -ENOMEM;
+
+ clk = devm_clk_get(dev, "usbdrd30");
+ if (IS_ERR(clk)) {
+ dev_err(dev, "Failed to get device clock\n");
+ return PTR_ERR(clk);
+ }
+
+ sphy->dev = dev;
+
+ if (dev->of_node) {
+ ret = samsung_usbphy_parse_dt(sphy);
+ if (ret < 0)
+ return ret;
+ } else {
+ if (!pdata) {
+ dev_err(dev, "no platform data specified\n");
+ return -EINVAL;
+ }
+ }
+
+ sphy->plat = pdata;
+ sphy->regs = phy_base;
+ sphy->clk = clk;
+ sphy->phy.dev = sphy->dev;
+ sphy->phy.label = "samsung-usb3phy";
+ sphy->phy.init = samsung_usb3phy_init;
+ sphy->phy.shutdown = samsung_usb3phy_shutdown;
+ sphy->drv_data = samsung_usbphy_get_driver_data(pdev);
+ sphy->ref_clk_freq = samsung_usbphy_get_refclk_freq(sphy);
+
+ spin_lock_init(&sphy->lock);
+
+ platform_set_drvdata(pdev, sphy);
+
+ return usb_add_phy(&sphy->phy, USB_PHY_TYPE_USB3);
+}
+
+static int samsung_usb3phy_remove(struct platform_device *pdev)
+{
+ struct samsung_usbphy *sphy = platform_get_drvdata(pdev);
+
+ usb_remove_phy(&sphy->phy);
+
+ if (sphy->pmuregs)
+ iounmap(sphy->pmuregs);
+ if (sphy->sysreg)
+ iounmap(sphy->sysreg);
+
+ return 0;
+}
+
+static struct samsung_usbphy_drvdata usb3phy_exynos5 = {
+ .cpu_type = TYPE_EXYNOS5250,
+ .devphy_en_mask = EXYNOS_USBPHY_ENABLE,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id samsung_usbphy_dt_match[] = {
+ {
+ .compatible = "samsung,exynos5250-usb3phy",
+ .data = &usb3phy_exynos5
+ },
+ {},
+};
+MODULE_DEVICE_TABLE(of, samsung_usbphy_dt_match);
+#endif
+
+static struct platform_device_id samsung_usbphy_driver_ids[] = {
+ {
+ .name = "exynos5250-usb3phy",
+ .driver_data = (unsigned long)&usb3phy_exynos5,
+ },
+ {},
+};
+
+MODULE_DEVICE_TABLE(platform, samsung_usbphy_driver_ids);
+
+static struct platform_driver samsung_usb3phy_driver = {
+ .probe = samsung_usb3phy_probe,
+ .remove = samsung_usb3phy_remove,
+ .id_table = samsung_usbphy_driver_ids,
+ .driver = {
+ .name = "samsung-usb3phy",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(samsung_usbphy_dt_match),
+ },
+};
+
+module_platform_driver(samsung_usb3phy_driver);
+
+MODULE_DESCRIPTION("Samsung USB 3.0 phy controller");
+MODULE_AUTHOR("Vivek Gautam <gautam.vivek@samsung.com>");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:samsung-usb3phy");