phy: add Marvell HSIC 28nm PHY

Add PHY driver for the Marvell HSIC 28nm PHY. This PHY is found in PXA1928
SOC.

Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/phy/phy-pxa-28nm-hsic.c b/drivers/phy/phy-pxa-28nm-hsic.c
new file mode 100644
index 0000000..234aacf
--- /dev/null
+++ b/drivers/phy/phy-pxa-28nm-hsic.c
@@ -0,0 +1,220 @@
+/*
+ * Copyright (C) 2015 Linaro, Ltd.
+ * Rob Herring <robh@kernel.org>
+ *
+ * Based on vendor driver:
+ * Copyright (C) 2013 Marvell Inc.
+ * Author: Chao Xie <xiechao.mail@gmail.com>
+ *
+ * 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/delay.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
+
+#define PHY_28NM_HSIC_CTRL			0x08
+#define PHY_28NM_HSIC_IMPCAL_CAL		0x18
+#define PHY_28NM_HSIC_PLL_CTRL01		0x1c
+#define PHY_28NM_HSIC_PLL_CTRL2			0x20
+#define PHY_28NM_HSIC_INT			0x28
+
+#define PHY_28NM_HSIC_PLL_SELLPFR_SHIFT		26
+#define PHY_28NM_HSIC_PLL_FBDIV_SHIFT		0
+#define PHY_28NM_HSIC_PLL_REFDIV_SHIFT		9
+
+#define PHY_28NM_HSIC_S2H_PU_PLL		BIT(10)
+#define PHY_28NM_HSIC_H2S_PLL_LOCK		BIT(15)
+#define PHY_28NM_HSIC_S2H_HSIC_EN		BIT(7)
+#define S2H_DRV_SE0_4RESUME			BIT(14)
+#define PHY_28NM_HSIC_H2S_IMPCAL_DONE		BIT(27)
+
+#define PHY_28NM_HSIC_CONNECT_INT		BIT(1)
+#define PHY_28NM_HSIC_HS_READY_INT		BIT(2)
+
+struct mv_hsic_phy {
+	struct phy		*phy;
+	struct platform_device	*pdev;
+	void __iomem		*base;
+	struct clk		*clk;
+};
+
+static bool wait_for_reg(void __iomem *reg, u32 mask, unsigned long timeout)
+{
+	timeout += jiffies;
+	while (time_is_after_eq_jiffies(timeout)) {
+		if ((readl(reg) & mask) == mask)
+			return true;
+		msleep(1);
+	}
+	return false;
+}
+
+static int mv_hsic_phy_init(struct phy *phy)
+{
+	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
+	struct platform_device *pdev = mv_phy->pdev;
+	void __iomem *base = mv_phy->base;
+
+	clk_prepare_enable(mv_phy->clk);
+
+	/* Set reference clock */
+	writel(0x1 << PHY_28NM_HSIC_PLL_SELLPFR_SHIFT |
+		0xf0 << PHY_28NM_HSIC_PLL_FBDIV_SHIFT |
+		0xd << PHY_28NM_HSIC_PLL_REFDIV_SHIFT,
+		base + PHY_28NM_HSIC_PLL_CTRL01);
+
+	/* Turn on PLL */
+	writel(readl(base + PHY_28NM_HSIC_PLL_CTRL2) |
+		PHY_28NM_HSIC_S2H_PU_PLL,
+		base + PHY_28NM_HSIC_PLL_CTRL2);
+
+	/* Make sure PHY PLL is locked */
+	if (!wait_for_reg(base + PHY_28NM_HSIC_PLL_CTRL2,
+	    PHY_28NM_HSIC_H2S_PLL_LOCK, HZ / 10)) {
+		dev_err(&pdev->dev, "HSIC PHY PLL not locked after 100mS.");
+		clk_disable_unprepare(mv_phy->clk);
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int mv_hsic_phy_power_on(struct phy *phy)
+{
+	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
+	struct platform_device *pdev = mv_phy->pdev;
+	void __iomem *base = mv_phy->base;
+	u32 reg;
+
+	reg = readl(base + PHY_28NM_HSIC_CTRL);
+	/* Avoid SE0 state when resume for some device will take it as reset */
+	reg &= ~S2H_DRV_SE0_4RESUME;
+	reg |= PHY_28NM_HSIC_S2H_HSIC_EN;	/* Enable HSIC PHY */
+	writel(reg, base + PHY_28NM_HSIC_CTRL);
+
+	/*
+	 *  Calibration Timing
+	 *		   ____________________________
+	 *  CAL START   ___|
+	 *			   ____________________
+	 *  CAL_DONE    ___________|
+	 *		   | 400us |
+	 */
+
+	/* Make sure PHY Calibration is ready */
+	if (!wait_for_reg(base + PHY_28NM_HSIC_IMPCAL_CAL,
+	    PHY_28NM_HSIC_H2S_IMPCAL_DONE, HZ / 10)) {
+		dev_warn(&pdev->dev, "HSIC PHY READY not set after 100mS.");
+		return -ETIMEDOUT;
+	}
+
+	/* Waiting for HSIC connect int*/
+	if (!wait_for_reg(base + PHY_28NM_HSIC_INT,
+	    PHY_28NM_HSIC_CONNECT_INT, HZ / 5)) {
+		dev_warn(&pdev->dev, "HSIC wait for connect interrupt timeout.");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int mv_hsic_phy_power_off(struct phy *phy)
+{
+	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
+	void __iomem *base = mv_phy->base;
+
+	writel(readl(base + PHY_28NM_HSIC_CTRL) & ~PHY_28NM_HSIC_S2H_HSIC_EN,
+		base + PHY_28NM_HSIC_CTRL);
+
+	return 0;
+}
+
+static int mv_hsic_phy_exit(struct phy *phy)
+{
+	struct mv_hsic_phy *mv_phy = phy_get_drvdata(phy);
+	void __iomem *base = mv_phy->base;
+
+	/* Turn off PLL */
+	writel(readl(base + PHY_28NM_HSIC_PLL_CTRL2) &
+		~PHY_28NM_HSIC_S2H_PU_PLL,
+		base + PHY_28NM_HSIC_PLL_CTRL2);
+
+	clk_disable_unprepare(mv_phy->clk);
+	return 0;
+}
+
+
+static const struct phy_ops hsic_ops = {
+	.init		= mv_hsic_phy_init,
+	.power_on	= mv_hsic_phy_power_on,
+	.power_off	= mv_hsic_phy_power_off,
+	.exit		= mv_hsic_phy_exit,
+	.owner		= THIS_MODULE,
+};
+
+static int mv_hsic_phy_probe(struct platform_device *pdev)
+{
+	struct phy_provider *phy_provider;
+	struct mv_hsic_phy *mv_phy;
+	struct resource *r;
+
+	mv_phy = devm_kzalloc(&pdev->dev, sizeof(*mv_phy), GFP_KERNEL);
+	if (!mv_phy)
+		return -ENOMEM;
+
+	mv_phy->pdev = pdev;
+
+	mv_phy->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(mv_phy->clk)) {
+		dev_err(&pdev->dev, "failed to get clock.\n");
+		return PTR_ERR(mv_phy->clk);
+	}
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	mv_phy->base = devm_ioremap_resource(&pdev->dev, r);
+	if (IS_ERR(mv_phy->base))
+		return PTR_ERR(mv_phy->base);
+
+	mv_phy->phy = devm_phy_create(&pdev->dev, pdev->dev.of_node, &hsic_ops);
+	if (IS_ERR(mv_phy->phy))
+		return PTR_ERR(mv_phy->phy);
+
+	phy_set_drvdata(mv_phy->phy, mv_phy);
+
+	phy_provider = devm_of_phy_provider_register(&pdev->dev, of_phy_simple_xlate);
+	return PTR_ERR_OR_ZERO(phy_provider);
+}
+
+static const struct of_device_id mv_hsic_phy_dt_match[] = {
+	{ .compatible = "marvell,pxa1928-hsic-phy", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mv_hsic_phy_dt_match);
+
+static struct platform_driver mv_hsic_phy_driver = {
+	.probe	= mv_hsic_phy_probe,
+	.driver = {
+		.name   = "mv-hsic-phy",
+		.of_match_table = of_match_ptr(mv_hsic_phy_dt_match),
+	},
+};
+module_platform_driver(mv_hsic_phy_driver);
+
+MODULE_AUTHOR("Rob Herring <robh@kernel.org>");
+MODULE_DESCRIPTION("Marvell HSIC phy driver");
+MODULE_LICENSE("GPL v2");