phy: Add support for S5PV210 to the Exynos USB 2.0 PHY driver

Add support for the Samsung's S5PV210 SoC to the Exynos USB 2.0 PHY driver.

Signed-off-by: Mateusz Krawczuk <m.krawczuk@partner.samsung.com>
[k.debski@samsung.com: cleanup and commit description]
[k.debski@samsung.com: make changes accordingly to the mailing list
comments]
Signed-off-by: Kamil Debski <k.debski@samsung.com>
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
diff --git a/drivers/phy/phy-s5pv210-usb2.c b/drivers/phy/phy-s5pv210-usb2.c
new file mode 100644
index 0000000..004d3207
--- /dev/null
+++ b/drivers/phy/phy-s5pv210-usb2.c
@@ -0,0 +1,187 @@
+/*
+ * Samsung SoC USB 1.1/2.0 PHY driver - S5PV210 support
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., Ltd.
+ * Authors: Kamil Debski <k.debski@samsung.com>
+ *
+ * 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/delay.h>
+#include <linux/io.h>
+#include <linux/phy/phy.h>
+#include "phy-samsung-usb2.h"
+
+/* Exynos USB PHY registers */
+
+/* PHY power control */
+#define S5PV210_UPHYPWR			0x0
+
+#define S5PV210_UPHYPWR_PHY0_SUSPEND	BIT(0)
+#define S5PV210_UPHYPWR_PHY0_PWR	BIT(3)
+#define S5PV210_UPHYPWR_PHY0_OTG_PWR	BIT(4)
+#define S5PV210_UPHYPWR_PHY0	( \
+	S5PV210_UPHYPWR_PHY0_SUSPEND | \
+	S5PV210_UPHYPWR_PHY0_PWR | \
+	S5PV210_UPHYPWR_PHY0_OTG_PWR)
+
+#define S5PV210_UPHYPWR_PHY1_SUSPEND	BIT(6)
+#define S5PV210_UPHYPWR_PHY1_PWR	BIT(7)
+#define S5PV210_UPHYPWR_PHY1 ( \
+	S5PV210_UPHYPWR_PHY1_SUSPEND | \
+	S5PV210_UPHYPWR_PHY1_PWR)
+
+/* PHY clock control */
+#define S5PV210_UPHYCLK			0x4
+
+#define S5PV210_UPHYCLK_PHYFSEL_MASK	(0x3 << 0)
+#define S5PV210_UPHYCLK_PHYFSEL_48MHZ	(0x0 << 0)
+#define S5PV210_UPHYCLK_PHYFSEL_24MHZ	(0x3 << 0)
+#define S5PV210_UPHYCLK_PHYFSEL_12MHZ	(0x2 << 0)
+
+#define S5PV210_UPHYCLK_PHY0_ID_PULLUP	BIT(2)
+#define S5PV210_UPHYCLK_PHY0_COMMON_ON	BIT(4)
+#define S5PV210_UPHYCLK_PHY1_COMMON_ON	BIT(7)
+
+/* PHY reset control */
+#define S5PV210_UPHYRST			0x8
+
+#define S5PV210_URSTCON_PHY0		BIT(0)
+#define S5PV210_URSTCON_OTG_HLINK	BIT(1)
+#define S5PV210_URSTCON_OTG_PHYLINK	BIT(2)
+#define S5PV210_URSTCON_PHY1_ALL	BIT(3)
+#define S5PV210_URSTCON_HOST_LINK_ALL	BIT(4)
+
+/* Isolation, configured in the power management unit */
+#define S5PV210_USB_ISOL_OFFSET		0x680c
+#define S5PV210_USB_ISOL_DEVICE		BIT(0)
+#define S5PV210_USB_ISOL_HOST		BIT(1)
+
+
+enum s5pv210_phy_id {
+	S5PV210_DEVICE,
+	S5PV210_HOST,
+	S5PV210_NUM_PHYS,
+};
+
+/*
+ * s5pv210_rate_to_clk() converts the supplied clock rate to the value that
+ * can be written to the phy register.
+ */
+static int s5pv210_rate_to_clk(unsigned long rate, u32 *reg)
+{
+	switch (rate) {
+	case 12 * MHZ:
+		*reg = S5PV210_UPHYCLK_PHYFSEL_12MHZ;
+		break;
+	case 24 * MHZ:
+		*reg = S5PV210_UPHYCLK_PHYFSEL_24MHZ;
+		break;
+	case 48 * MHZ:
+		*reg = S5PV210_UPHYCLK_PHYFSEL_48MHZ;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static void s5pv210_isol(struct samsung_usb2_phy_instance *inst, bool on)
+{
+	struct samsung_usb2_phy_driver *drv = inst->drv;
+	u32 mask;
+
+	switch (inst->cfg->id) {
+	case S5PV210_DEVICE:
+		mask = S5PV210_USB_ISOL_DEVICE;
+		break;
+	case S5PV210_HOST:
+		mask = S5PV210_USB_ISOL_HOST;
+		break;
+	default:
+		return;
+	};
+
+	regmap_update_bits(drv->reg_pmu, S5PV210_USB_ISOL_OFFSET,
+							mask, on ? 0 : mask);
+}
+
+static void s5pv210_phy_pwr(struct samsung_usb2_phy_instance *inst, bool on)
+{
+	struct samsung_usb2_phy_driver *drv = inst->drv;
+	u32 rstbits = 0;
+	u32 phypwr = 0;
+	u32 rst;
+	u32 pwr;
+
+	switch (inst->cfg->id) {
+	case S5PV210_DEVICE:
+		phypwr =	S5PV210_UPHYPWR_PHY0;
+		rstbits =	S5PV210_URSTCON_PHY0;
+		break;
+	case S5PV210_HOST:
+		phypwr =	S5PV210_UPHYPWR_PHY1;
+		rstbits =	S5PV210_URSTCON_PHY1_ALL |
+				S5PV210_URSTCON_HOST_LINK_ALL;
+		break;
+	};
+
+	if (on) {
+		writel(drv->ref_reg_val, drv->reg_phy + S5PV210_UPHYCLK);
+
+		pwr = readl(drv->reg_phy + S5PV210_UPHYPWR);
+		pwr &= ~phypwr;
+		writel(pwr, drv->reg_phy + S5PV210_UPHYPWR);
+
+		rst = readl(drv->reg_phy + S5PV210_UPHYRST);
+		rst |= rstbits;
+		writel(rst, drv->reg_phy + S5PV210_UPHYRST);
+		udelay(10);
+		rst &= ~rstbits;
+		writel(rst, drv->reg_phy + S5PV210_UPHYRST);
+	} else {
+		pwr = readl(drv->reg_phy + S5PV210_UPHYPWR);
+		pwr |= phypwr;
+		writel(pwr, drv->reg_phy + S5PV210_UPHYPWR);
+	}
+}
+
+static int s5pv210_power_on(struct samsung_usb2_phy_instance *inst)
+{
+	s5pv210_isol(inst, 0);
+	s5pv210_phy_pwr(inst, 1);
+
+	return 0;
+}
+
+static int s5pv210_power_off(struct samsung_usb2_phy_instance *inst)
+{
+	s5pv210_phy_pwr(inst, 0);
+	s5pv210_isol(inst, 1);
+
+	return 0;
+}
+
+static const struct samsung_usb2_common_phy s5pv210_phys[S5PV210_NUM_PHYS] = {
+	[S5PV210_DEVICE] = {
+		.label		= "device",
+		.id		= S5PV210_DEVICE,
+		.power_on	= s5pv210_power_on,
+		.power_off	= s5pv210_power_off,
+	},
+	[S5PV210_HOST] = {
+		.label		= "host",
+		.id		= S5PV210_HOST,
+		.power_on	= s5pv210_power_on,
+		.power_off	= s5pv210_power_off,
+	},
+};
+
+const struct samsung_usb2_phy_config s5pv210_usb2_phy_config = {
+	.num_phys	= ARRAY_SIZE(s5pv210_phys),
+	.phys		= s5pv210_phys,
+	.rate_to_clk	= s5pv210_rate_to_clk,
+};