musb: MSC host support for AM35x

Tested MSC Host on AM3517EVM.

Signed-off-by: Ajay Kumar Gupta <ajay.gupta@ti.com>

1 files changed, 118 insertions, 0 deletions

diff --git a/drivers/usb/musb/am35x.c b/drivers/usb/musb/am35x.c
new file mode 100644
index 0000000..2024940
--- /dev/null
+++ b/drivers/usb/musb/am35x.c
@@ -0,0 +1,118 @@
+/*
+ * am35x.c - TI's AM35x platform specific usb wrapper functions.
+ *
+ * Author: Ajay Kumar Gupta <ajay.gupta@ti.com>
+ *
+ * Based on drivers/usb/musb/da8xx.c
+ *
+ * Copyright (c) 2010 Texas Instruments Incorporated
+ *
+ * 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.
+ *
+ * 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 <common.h>
+
+#include "am35x.h"
+
+/* MUSB platform configuration */
+struct musb_config musb_cfg = {
+	.regs		= (struct musb_regs *)AM35X_USB_OTG_CORE_BASE,
+	.timeout	= AM35X_USB_OTG_TIMEOUT,
+	.musb_speed	= 0,
+};
+
+/*
+ * Enable the USB phy
+ */
+static u8 phy_on(void)
+{
+	u32 devconf2;
+	u32 timeout;
+
+	devconf2 = readl(&am35x_scm_general_regs->devconf2);
+
+	devconf2 &= ~(DEVCONF2_RESET | DEVCONF2_PHYPWRDN | DEVCONF2_OTGPWRDN |
+		      DEVCONF2_OTGMODE | DEVCONF2_REFFREQ |
+		      DEVCONF2_PHY_GPIOMODE);
+	devconf2 |= DEVCONF2_SESENDEN | DEVCONF2_VBDTCTEN | DEVCONF2_PHY_PLLON |
+		    DEVCONF2_REFFREQ_13MHZ | DEVCONF2_DATPOL;
+
+	writel(devconf2, &am35x_scm_general_regs->devconf2);
+
+	/* wait until the USB phy is turned on */
+	timeout = musb_cfg.timeout;
+	while (timeout--)
+		if (readl(&am35x_scm_general_regs->devconf2) & DEVCONF2_PHYCKGD)
+			return 1;
+
+	/* USB phy was not turned on */
+	return 0;
+}
+
+/*
+ * Disable the USB phy
+ */
+static void phy_off(void)
+{
+	u32 devconf2;
+
+	/*
+	 * Power down the on-chip PHY.
+	 */
+	devconf2 = readl(&am35x_scm_general_regs->devconf2);
+
+	devconf2 &= ~DEVCONF2_PHY_PLLON;
+	devconf2 |= DEVCONF2_PHYPWRDN | DEVCONF2_OTGPWRDN;
+	writel(devconf2, &am35x_scm_general_regs->devconf2);
+}
+
+/*
+ * This function performs platform specific initialization for usb0.
+ */
+int musb_platform_init(void)
+{
+	u32 revision;
+	u32 sw_reset;
+
+	/* global usb reset */
+	sw_reset = readl(&am35x_scm_general_regs->ip_sw_reset);
+	sw_reset |= (1 << 0);
+	writel(sw_reset, &am35x_scm_general_regs->ip_sw_reset);
+	sw_reset &= ~(1 << 0);
+	writel(sw_reset, &am35x_scm_general_regs->ip_sw_reset);
+
+	/* reset the controller */
+	writel(0x1, &am35x_usb_regs->control);
+	udelay(5000);
+
+	/* start the on-chip usb phy and its pll */
+	if (phy_on() == 0)
+		return -1;
+
+	/* Returns zero if e.g. not clocked */
+	revision = readl(&am35x_usb_regs->revision);
+	if (revision == 0)
+		return -1;
+
+	return 0;
+}
+
+/*
+ * This function performs platform specific deinitialization for usb0.
+ */
+void musb_platform_deinit(void)
+{
+	/* Turn off the phy */
+	phy_off();
+}