--- /dev/null
+/*
+ * Renesas R-Car Gen2 PHY driver
+ *
+ * Copyright (C) 2014 Renesas Solutions Corp.
+ * Copyright (C) 2014 Cogent Embedded, Inc.
+ *
+ * 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.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+
+#include <asm/cmpxchg.h>
+
+#define USBHS_LPSTS 0x02
+#define USBHS_UGCTRL 0x80
+#define USBHS_UGCTRL2 0x84
+#define USBHS_UGSTS 0x88 /* From technical update */
+
+/* Low Power Status register (LPSTS) */
+#define USBHS_LPSTS_SUSPM 0x4000
+
+/* USB General control register (UGCTRL) */
+#define USBHS_UGCTRL_CONNECT 0x00000004
+#define USBHS_UGCTRL_PLLRESET 0x00000001
+
+/* USB General control register 2 (UGCTRL2) */
+#define USBHS_UGCTRL2_USB2SEL 0x80000000
+#define USBHS_UGCTRL2_USB2SEL_PCI 0x00000000
+#define USBHS_UGCTRL2_USB2SEL_USB30 0x80000000
+#define USBHS_UGCTRL2_USB0SEL 0x00000030
+#define USBHS_UGCTRL2_USB0SEL_PCI 0x00000010
+#define USBHS_UGCTRL2_USB0SEL_HS_USB 0x00000030
+
+/* USB General status register (UGSTS) */
+#define USBHS_UGSTS_LOCK 0x00000100 /* From technical update */
+
+#define PHYS_PER_CHANNEL 2
+
+struct rcar_gen2_phy {
+ struct phy *phy;
+ struct rcar_gen2_channel *channel;
+ int number;
+ u32 select_value;
+};
+
+struct rcar_gen2_channel {
+ struct device_node *of_node;
+ struct rcar_gen2_phy_driver *drv;
+ struct rcar_gen2_phy phys[PHYS_PER_CHANNEL];
+ int selected_phy;
+ u32 select_mask;
+};
+
+struct rcar_gen2_phy_driver {
+ void __iomem *base;
+ struct clk *clk;
+ spinlock_t lock;
+ int num_channels;
+ struct rcar_gen2_channel *channels;
+};
+
+static int rcar_gen2_phy_init(struct phy *p)
+{
+ struct rcar_gen2_phy *phy = phy_get_drvdata(p);
+ struct rcar_gen2_channel *channel = phy->channel;
+ struct rcar_gen2_phy_driver *drv = channel->drv;
+ unsigned long flags;
+ u32 ugctrl2;
+
+ /*
+ * Try to acquire exclusive access to PHY. The first driver calling
+ * phy_init() on a given channel wins, and all attempts to use another
+ * PHY on this channel will fail until phy_exit() is called by the first
+ * driver. Achieving this with cmpxcgh() should be SMP-safe.
+ */
+ if (cmpxchg(&channel->selected_phy, -1, phy->number) != -1)
+ return -EBUSY;
+
+ clk_prepare_enable(drv->clk);
+
+ spin_lock_irqsave(&drv->lock, flags);
+ ugctrl2 = readl(drv->base + USBHS_UGCTRL2);
+ ugctrl2 &= ~channel->select_mask;
+ ugctrl2 |= phy->select_value;
+ writel(ugctrl2, drv->base + USBHS_UGCTRL2);
+ spin_unlock_irqrestore(&drv->lock, flags);
+ return 0;
+}
+
+static int rcar_gen2_phy_exit(struct phy *p)
+{
+ struct rcar_gen2_phy *phy = phy_get_drvdata(p);
+ struct rcar_gen2_channel *channel = phy->channel;
+
+ clk_disable_unprepare(channel->drv->clk);
+
+ channel->selected_phy = -1;
+
+ return 0;
+}
+
+static int rcar_gen2_phy_power_on(struct phy *p)
+{
+ struct rcar_gen2_phy *phy = phy_get_drvdata(p);
+ struct rcar_gen2_phy_driver *drv = phy->channel->drv;
+ void __iomem *base = drv->base;
+ unsigned long flags;
+ u32 value;
+ int err = 0, i;
+
+ /* Skip if it's not USBHS */
+ if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB)
+ return 0;
+
+ spin_lock_irqsave(&drv->lock, flags);
+
+ /* Power on USBHS PHY */
+ value = readl(base + USBHS_UGCTRL);
+ value &= ~USBHS_UGCTRL_PLLRESET;
+ writel(value, base + USBHS_UGCTRL);
+
+ value = readw(base + USBHS_LPSTS);
+ value |= USBHS_LPSTS_SUSPM;
+ writew(value, base + USBHS_LPSTS);
+
+ for (i = 0; i < 20; i++) {
+ value = readl(base + USBHS_UGSTS);
+ if ((value & USBHS_UGSTS_LOCK) == USBHS_UGSTS_LOCK) {
+ value = readl(base + USBHS_UGCTRL);
+ value |= USBHS_UGCTRL_CONNECT;
+ writel(value, base + USBHS_UGCTRL);
+ goto out;
+ }
+ udelay(1);
+ }
+
+ /* Timed out waiting for the PLL lock */
+ err = -ETIMEDOUT;
+
+out:
+ spin_unlock_irqrestore(&drv->lock, flags);
+
+ return err;
+}
+
+static int rcar_gen2_phy_power_off(struct phy *p)
+{
+ struct rcar_gen2_phy *phy = phy_get_drvdata(p);
+ struct rcar_gen2_phy_driver *drv = phy->channel->drv;
+ void __iomem *base = drv->base;
+ unsigned long flags;
+ u32 value;
+
+ /* Skip if it's not USBHS */
+ if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB)
+ return 0;
+
+ spin_lock_irqsave(&drv->lock, flags);
+
+ /* Power off USBHS PHY */
+ value = readl(base + USBHS_UGCTRL);
+ value &= ~USBHS_UGCTRL_CONNECT;
+ writel(value, base + USBHS_UGCTRL);
+
+ value = readw(base + USBHS_LPSTS);
+ value &= ~USBHS_LPSTS_SUSPM;
+ writew(value, base + USBHS_LPSTS);
+
+ value = readl(base + USBHS_UGCTRL);
+ value |= USBHS_UGCTRL_PLLRESET;
+ writel(value, base + USBHS_UGCTRL);
+
+ spin_unlock_irqrestore(&drv->lock, flags);
+
+ return 0;
+}
+
+static struct phy_ops rcar_gen2_phy_ops = {
+ .init = rcar_gen2_phy_init,
+ .exit = rcar_gen2_phy_exit,
+ .power_on = rcar_gen2_phy_power_on,
+ .power_off = rcar_gen2_phy_power_off,
+ .owner = THIS_MODULE,
+};
+
+static const struct of_device_id rcar_gen2_phy_match_table[] = {
+ { .compatible = "renesas,usb-phy-r8a7790" },
+ { .compatible = "renesas,usb-phy-r8a7791" },
+ { }
+};
+MODULE_DEVICE_TABLE(of, rcar_gen2_phy_match_table);
+
+static struct phy *rcar_gen2_phy_xlate(struct device *dev,
+ struct of_phandle_args *args)
+{
+ struct rcar_gen2_phy_driver *drv;
+ struct device_node *np = args->np;
+ int i;
+
+ if (!of_device_is_available(np)) {
+ dev_warn(dev, "Requested PHY is disabled\n");
+ return ERR_PTR(-ENODEV);
+ }
+
+ drv = dev_get_drvdata(dev);
+ if (!drv)
+ return ERR_PTR(-EINVAL);
+
+ for (i = 0; i < drv->num_channels; i++) {
+ if (np == drv->channels[i].of_node)
+ break;
+ }
+
+ if (i >= drv->num_channels || args->args[0] >= 2)
+ return ERR_PTR(-ENODEV);
+
+ return drv->channels[i].phys[args->args[0]].phy;
+}
+
+static const u32 select_mask[] = {
+ [0] = USBHS_UGCTRL2_USB0SEL,
+ [2] = USBHS_UGCTRL2_USB2SEL,
+};
+
+static const u32 select_value[][PHYS_PER_CHANNEL] = {
+ [0] = { USBHS_UGCTRL2_USB0SEL_PCI, USBHS_UGCTRL2_USB0SEL_HS_USB },
+ [2] = { USBHS_UGCTRL2_USB2SEL_PCI, USBHS_UGCTRL2_USB2SEL_USB30 },
+};
+
+static int rcar_gen2_phy_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct rcar_gen2_phy_driver *drv;
+ struct phy_provider *provider;
+ struct device_node *np;
+ struct resource *res;
+ void __iomem *base;
+ struct clk *clk;
+ int i = 0;
+
+ if (!dev->of_node) {
+ dev_err(dev,
+ "This driver is required to be instantiated from device tree\n");
+ return -EINVAL;
+ }
+
+ clk = devm_clk_get(dev, "usbhs");
+ if (IS_ERR(clk)) {
+ dev_err(dev, "Can't get USBHS clock\n");
+ return PTR_ERR(clk);
+ }
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ base = devm_ioremap_resource(dev, res);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
+ if (!drv)
+ return -ENOMEM;
+
+ spin_lock_init(&drv->lock);
+
+ drv->clk = clk;
+ drv->base = base;
+
+ drv->num_channels = of_get_child_count(dev->of_node);
+ drv->channels = devm_kcalloc(dev, drv->num_channels,
+ sizeof(struct rcar_gen2_channel),
+ GFP_KERNEL);
+ if (!drv->channels)
+ return -ENOMEM;
+
+ for_each_child_of_node(dev->of_node, np) {
+ struct rcar_gen2_channel *channel = drv->channels + i;
+ u32 channel_num;
+ int error, n;
+
+ channel->of_node = np;
+ channel->drv = drv;
+ channel->selected_phy = -1;
+
+ error = of_property_read_u32(np, "reg", &channel_num);
+ if (error || channel_num > 2) {
+ dev_err(dev, "Invalid \"reg\" property\n");
+ return error;
+ }
+ channel->select_mask = select_mask[channel_num];
+
+ for (n = 0; n < PHYS_PER_CHANNEL; n++) {
+ struct rcar_gen2_phy *phy = &channel->phys[n];
+
+ phy->channel = channel;
+ phy->number = n;
+ phy->select_value = select_value[channel_num][n];
+
+ phy->phy = devm_phy_create(dev, NULL,
+ &rcar_gen2_phy_ops);
+ if (IS_ERR(phy->phy)) {
+ dev_err(dev, "Failed to create PHY\n");
+ return PTR_ERR(phy->phy);
+ }
+ phy_set_drvdata(phy->phy, phy);
+ }
+
+ i++;
+ }
+
+ provider = devm_of_phy_provider_register(dev, rcar_gen2_phy_xlate);
+ if (IS_ERR(provider)) {
+ dev_err(dev, "Failed to register PHY provider\n");
+ return PTR_ERR(provider);
+ }
+
+ dev_set_drvdata(dev, drv);
+
+ return 0;
+}
+
+static struct platform_driver rcar_gen2_phy_driver = {
+ .driver = {
+ .name = "phy_rcar_gen2",
+ .of_match_table = rcar_gen2_phy_match_table,
+ },
+ .probe = rcar_gen2_phy_probe,
+};
+
+module_platform_driver(rcar_gen2_phy_driver);
+
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Renesas R-Car Gen2 PHY");
+MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");
Code Review / kvmfornfv.git / blobdiff