usb: otg: Adding twl6030-usb transceiver driver for OMAP4430

Adding the twl6030-usb transceiver support for OMAP4 musb driver.

OMAP4 supports 2 types of transceiver interface.

1. UTMI: The PHY is embedded within OMAP4. The transceiver functionality
is split between the twl6030 PMIC chip and OMAP4430. The VBUS, ID pin
sensing and OTG SRP generation part is integrated in TWL6030 and UTMI PHY
functionality is embedded within the OMAP4430.

There is no direct interactions between the MUSB controller and TWL6030
chip to communicate the session-valid, session-end and ID-GND events.
It has to be done through a software by setting/resetting bits in
one of the control module register of OMAP4430 which in turn toggles
the appropriate signals to MUSB controller.

The internal transceiver has functional clocks and
powerdown bits to powerdown the PHY for power saving.

Since there is no option available for having 2 transceiver drivers
for one USB controller, internal PHY specific APIs are passed through
plaform_data function pointers to use in the twl6030-usb transceiver
driver.

2. ULPI interface is provided for off-chip transceivers.

Signed-off-by: Hema HK <hemahk@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 149 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/omap_phy_internal.c b/arch/arm/mach-omap2/omap_phy_internal.c
new file mode 100644
index 000000000000..745252c60e32
--- /dev/null
+++ b/arch/arm/mach-omap2/omap_phy_internal.c
@@ -0,0 +1,149 @@
+/*
+  * This file configures the internal USB PHY in OMAP4430. Used
+  * with TWL6030 transceiver and MUSB on OMAP4430.
+  *
+  * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com
+  * This program is free software; you can redistribute it and/or modify
+  * it under the terms of the GNU General Public License as published by
+  * the Free Software Foundation; either version 2 of the License, or
+  * (at your option) any later version.
+  *
+  * Author: Hema HK <hemahk@ti.com>
+  *
+  * 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.
+  *
+  * You should have received a copy of the GNU General Public License
+  * along with this program; if not, write to the Free Software
+  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+  *
+  */
+
+#include <linux/types.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/err.h>
+#include <linux/usb.h>
+
+#include <plat/usb.h>
+
+/* OMAP control module register for UTMI PHY */
+#define CONTROL_DEV_CONF		0x300
+#define PHY_PD				0x1
+
+#define USBOTGHS_CONTROL		0x33c
+#define	AVALID				BIT(0)
+#define	BVALID				BIT(1)
+#define	VBUSVALID			BIT(2)
+#define	SESSEND				BIT(3)
+#define	IDDIG				BIT(4)
+
+static struct clk *phyclk, *clk48m, *clk32k;
+static void __iomem *ctrl_base;
+
+int omap4430_phy_init(struct device *dev)
+{
+	ctrl_base = ioremap(OMAP443X_SCM_BASE, SZ_1K);
+	if (!ctrl_base) {
+		dev_err(dev, "control module ioremap failed\n");
+		return -ENOMEM;
+	}
+	/* Power down the phy */
+	__raw_writel(PHY_PD, ctrl_base + CONTROL_DEV_CONF);
+	phyclk = clk_get(dev, "ocp2scp_usb_phy_ick");
+
+	if (IS_ERR(phyclk)) {
+		dev_err(dev, "cannot clk_get ocp2scp_usb_phy_ick\n");
+		iounmap(ctrl_base);
+		return PTR_ERR(phyclk);
+	}
+
+	clk48m = clk_get(dev, "ocp2scp_usb_phy_phy_48m");
+	if (IS_ERR(clk48m)) {
+		dev_err(dev, "cannot clk_get ocp2scp_usb_phy_phy_48m\n");
+		clk_put(phyclk);
+		iounmap(ctrl_base);
+		return PTR_ERR(clk48m);
+	}
+
+	clk32k = clk_get(dev, "usb_phy_cm_clk32k");
+	if (IS_ERR(clk32k)) {
+		dev_err(dev, "cannot clk_get usb_phy_cm_clk32k\n");
+		clk_put(phyclk);
+		clk_put(clk48m);
+		iounmap(ctrl_base);
+		return PTR_ERR(clk32k);
+	}
+	return 0;
+}
+
+int omap4430_phy_set_clk(struct device *dev, int on)
+{
+	static int state;
+
+	if (on && !state) {
+		/* Enable the phy clocks */
+		clk_enable(phyclk);
+		clk_enable(clk48m);
+		clk_enable(clk32k);
+		state = 1;
+	} else if (state) {
+		/* Disable the phy clocks */
+		clk_disable(phyclk);
+		clk_disable(clk48m);
+		clk_disable(clk32k);
+		state = 0;
+	}
+	return 0;
+}
+
+int omap4430_phy_power(struct device *dev, int ID, int on)
+{
+	if (on) {
+		/* enabled the clocks */
+		omap4430_phy_set_clk(dev, 1);
+		/* power on the phy */
+		if (__raw_readl(ctrl_base + CONTROL_DEV_CONF) & PHY_PD) {
+			__raw_writel(~PHY_PD, ctrl_base + CONTROL_DEV_CONF);
+			mdelay(200);
+		}
+		if (ID)
+			/* enable VBUS valid, IDDIG groung */
+			__raw_writel(AVALID | VBUSVALID, ctrl_base +
+							USBOTGHS_CONTROL);
+		else
+			/*
+			 * Enable VBUS Valid, AValid and IDDIG
+			 * high impedence
+			 */
+			__raw_writel(IDDIG | AVALID | VBUSVALID,
+						ctrl_base + USBOTGHS_CONTROL);
+	} else {
+		/* Enable session END and IDIG to high impedence. */
+		__raw_writel(SESSEND | IDDIG, ctrl_base +
+					USBOTGHS_CONTROL);
+		/* Disable the clocks */
+		omap4430_phy_set_clk(dev, 0);
+		/* Power down the phy */
+		__raw_writel(PHY_PD, ctrl_base + CONTROL_DEV_CONF);
+	}
+
+	return 0;
+}
+
+int omap4430_phy_exit(struct device *dev)
+{
+	if (ctrl_base)
+		iounmap(ctrl_base);
+	if (phyclk)
+		clk_put(phyclk);
+	if (clk48m)
+		clk_put(clk48m);
+	if (clk32k)
+		clk_put(clk32k);
+
+	return 0;
+}