phy: add Broadcom Kona USB2 PHY driver

Add a driver for the internal Broadcom Kona USB 2.0 PHY found
on the BCM281xx family of SoCs.

Signed-off-by: Matt Porter <mporter@linaro.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

3 files changed, 165 insertions, 0 deletions

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 330ef2d06567..a49e85349d81 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -51,4 +51,10 @@ config PHY_EXYNOS_DP_VIDEO
         help
           Support for Display Port PHY found on Samsung EXYNOS SoCs.
 
+config BCM_KONA_USB2_PHY
+        tristate "Broadcom Kona USB2 PHY Driver"
+        depends on GENERIC_PHY
+        help
+          Enable this to support the Broadcom Kona USB 2.0 PHY.
+
 endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index d0caae9cfb83..c447f1a98ac5 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -3,6 +3,7 @@
 #
 
 obj-$(CONFIG_GENERIC_PHY)               += phy-core.o
+obj-$(CONFIG_BCM_KONA_USB2_PHY)         += phy-bcm-kona-usb2.o
 obj-$(CONFIG_PHY_EXYNOS_DP_VIDEO)       += phy-exynos-dp-video.o
 obj-$(CONFIG_PHY_EXYNOS_MIPI_VIDEO)     += phy-exynos-mipi-video.o
 obj-$(CONFIG_OMAP_USB2)                 += phy-omap-usb2.o
diff --git a/drivers/phy/phy-bcm-kona-usb2.c b/drivers/phy/phy-bcm-kona-usb2.c
new file mode 100644
index 000000000000..efc5c1a13a5d
--- /dev/null
+++ b/drivers/phy/phy-bcm-kona-usb2.c
@@ -0,0 +1,158 @@
+/*
+ * phy-bcm-kona-usb2.c - Broadcom Kona USB2 Phy Driver
+ *
+ * Copyright (C) 2013 Linaro Limited
+ * Matt Porter <mporter@linaro.org>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+
+#define OTGCTL                  (0)
+#define OTGCTL_OTGSTAT2         BIT(31)
+#define OTGCTL_OTGSTAT1         BIT(30)
+#define OTGCTL_PRST_N_SW        BIT(11)
+#define OTGCTL_HRESET_N         BIT(10)
+#define OTGCTL_UTMI_LINE_STATE1 BIT(9)
+#define OTGCTL_UTMI_LINE_STATE0 BIT(8)
+
+#define P1CTL                   (8)
+#define P1CTL_SOFT_RESET        BIT(1)
+#define P1CTL_NON_DRIVING       BIT(0)
+
+struct bcm_kona_usb {
+        void __iomem *regs;
+};
+
+static void bcm_kona_usb_phy_power(struct bcm_kona_usb *phy, int on)
+{
+        u32 val;
+
+        val = readl(phy->regs + OTGCTL);
+        if (on) {
+                /* Configure and power PHY */
+                val &= ~(OTGCTL_OTGSTAT2 | OTGCTL_OTGSTAT1 |
+                         OTGCTL_UTMI_LINE_STATE1 | OTGCTL_UTMI_LINE_STATE0);
+                val |= OTGCTL_PRST_N_SW | OTGCTL_HRESET_N;
+        } else {
+                val &= ~(OTGCTL_PRST_N_SW | OTGCTL_HRESET_N);
+        }
+        writel(val, phy->regs + OTGCTL);
+}
+
+static int bcm_kona_usb_phy_init(struct phy *gphy)
+{
+        struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
+        u32 val;
+
+        /* Soft reset PHY */
+        val = readl(phy->regs + P1CTL);
+        val &= ~P1CTL_NON_DRIVING;
+        val |= P1CTL_SOFT_RESET;
+        writel(val, phy->regs + P1CTL);
+        writel(val & ~P1CTL_SOFT_RESET, phy->regs + P1CTL);
+        /* Reset needs to be asserted for 2ms */
+        mdelay(2);
+        writel(val | P1CTL_SOFT_RESET, phy->regs + P1CTL);
+
+        return 0;
+}
+
+static int bcm_kona_usb_phy_power_on(struct phy *gphy)
+{
+        struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
+
+        bcm_kona_usb_phy_power(phy, 1);
+
+        return 0;
+}
+
+static int bcm_kona_usb_phy_power_off(struct phy *gphy)
+{
+        struct bcm_kona_usb *phy = phy_get_drvdata(gphy);
+
+        bcm_kona_usb_phy_power(phy, 0);
+
+        return 0;
+}
+
+static struct phy_ops ops = {
+        .init           = bcm_kona_usb_phy_init,
+        .power_on       = bcm_kona_usb_phy_power_on,
+        .power_off      = bcm_kona_usb_phy_power_off,
+        .owner          = THIS_MODULE,
+};
+
+static int bcm_kona_usb2_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct bcm_kona_usb *phy;
+        struct resource *res;
+        struct phy *gphy;
+        struct phy_provider *phy_provider;
+
+        phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+        if (!phy)
+                return -ENOMEM;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        phy->regs = devm_ioremap_resource(&pdev->dev, res);
+        if (IS_ERR(phy->regs))
+                return PTR_ERR(phy->regs);
+
+        platform_set_drvdata(pdev, phy);
+
+        gphy = devm_phy_create(dev, &ops, NULL);
+        if (IS_ERR(gphy))
+                return PTR_ERR(gphy);
+
+        /* The Kona PHY supports an 8-bit wide UTMI interface */
+        phy_set_bus_width(gphy, 8);
+
+        phy_set_drvdata(gphy, phy);
+
+        phy_provider = devm_of_phy_provider_register(dev,
+                        of_phy_simple_xlate);
+        if (IS_ERR(phy_provider))
+                return PTR_ERR(phy_provider);
+
+        return 0;
+}
+
+static const struct of_device_id bcm_kona_usb2_dt_ids[] = {
+        { .compatible = "brcm,kona-usb2-phy" },
+        { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, bcm_kona_usb2_dt_ids);
+
+static struct platform_driver bcm_kona_usb2_driver = {
+        .probe          = bcm_kona_usb2_probe,
+        .driver         = {
+                .name   = "bcm-kona-usb2",
+                .owner  = THIS_MODULE,
+                .of_match_table = bcm_kona_usb2_dt_ids,
+        },
+};
+
+module_platform_driver(bcm_kona_usb2_driver);
+
+MODULE_ALIAS("platform:bcm-kona-usb2");
+MODULE_AUTHOR("Matt Porter <mporter@linaro.org>");
+MODULE_DESCRIPTION("BCM Kona USB 2.0 PHY driver");
+MODULE_LICENSE("GPL v2");