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authorSergei Shtylyov <sergei.shtylyov@cogentembedded.com>2014-07-22 23:27:14 +0400
committerKishon Vijay Abraham I <kishon@ti.com>2014-09-24 15:18:31 +0530
commit1233f59f745b237d85f12aa9cf12ffab469f322d (patch)
tree933473b42ec28e4ffcd9ea598b384aca6056d5a1 /drivers/phy
parent452b6361c4d9baf6940adb7b1316e0f386c39799 (diff)
phy: Renesas R-Car Gen2 PHY driver
This PHY, though formally being a part of Renesas USBHS controller, contains the UGCTRL2 register that controls multiplexing of the USB ports (Renesas calls them channels) to the different USB controllers: channel 0 can be connected to either PCI EHCI/OHCI or USBHS controllers, channel 2 can be connected to PCI EHCI/OHCI or xHCI controllers. This is a new driver for this USB PHY currently already supported under drivers/ usb/phy/. The reason for writing the new driver was the requirement that the multiplexing of USB channels to the controller be dynamic, depending on what USB drivers are loaded, rather than static as provided by the old driver. The infrastructure provided by drivers/phy/phy-core.c seems to fit that purpose ideally. The new driver only supports device tree probing for now. Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com> Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Diffstat (limited to 'drivers/phy')
-rw-r--r--drivers/phy/Kconfig7
-rw-r--r--drivers/phy/Makefile1
-rw-r--r--drivers/phy/phy-rcar-gen2.c341
3 files changed, 349 insertions, 0 deletions
diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index f833aa271a2..1802fa767aa 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -48,6 +48,13 @@ config PHY_MIPHY365X
Enable this to support the miphy transceiver (for SATA/PCIE)
that is part of STMicroelectronics STiH41x SoC series.
+config PHY_RCAR_GEN2
+ tristate "Renesas R-Car generation 2 USB PHY driver"
+ depends on ARCH_SHMOBILE
+ depends on GENERIC_PHY
+ help
+ Support for USB PHY found on Renesas R-Car generation 2 SoCs.
+
config OMAP_CONTROL_PHY
tristate "OMAP CONTROL PHY Driver"
depends on ARCH_OMAP2PLUS || COMPILE_TEST
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 95c69ed5ed4..8ac9df5bd06 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO) += phy-exynos-dp-video.o
obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO) += phy-exynos-mipi-video.o
obj-$(CONFIG_PHY_MVEBU_SATA) += phy-mvebu-sata.o
obj-$(CONFIG_PHY_MIPHY365X) += phy-miphy365x.o
+obj-$(CONFIG_PHY_RCAR_GEN2) += phy-rcar-gen2.o
obj-$(CONFIG_OMAP_CONTROL_PHY) += phy-omap-control.o
obj-$(CONFIG_OMAP_USB2) += phy-omap-usb2.o
obj-$(CONFIG_TI_PIPE3) += phy-ti-pipe3.o
diff --git a/drivers/phy/phy-rcar-gen2.c b/drivers/phy/phy-rcar-gen2.c
new file mode 100644
index 00000000000..2793af17799
--- /dev/null
+++ b/drivers/phy/phy-rcar-gen2.c
@@ -0,0 +1,341 @@
+/*
+ * 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 /* The manuals have 0x90 */
+
+/* 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 0x00000300 /* The manuals have 0x3 */
+
+#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, NULL);
+ 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>");