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+/*
+ * IP block integration code for the HDQ1W/1-wire IP block
+ *
+ * Copyright (C) 2012 Texas Instruments, Inc.
+ * Paul Walmsley
+ *
+ * Based on the I2C reset code in arch/arm/mach-omap2/i2c.c by
+ * Avinash.H.M <avinashhm@ti.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.
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#include <plat/omap_hwmod.h>
+#include <plat/hdq1w.h>
+
+#include "common.h"
+
+/* Maximum microseconds to wait for OMAP module to softreset */
+#define MAX_MODULE_SOFTRESET_WAIT 10000
+
+/**
+ * omap_hdq1w_reset - reset the OMAP HDQ1W module
+ * @oh: struct omap_hwmod *
+ *
+ * OCP soft reset the HDQ1W IP block. Section 20.6.1.4 "HDQ1W/1-Wire
+ * Software Reset" of the OMAP34xx Technical Reference Manual Revision
+ * ZR (SWPU223R) does not include the rather important fact that, for
+ * the reset to succeed, the HDQ1W module's internal clock gate must be
+ * programmed to allow the clock to propagate to the rest of the
+ * module. In this sense, it's rather similar to the I2C custom reset
+ * function. Returns 0.
+ */
+int omap_hdq1w_reset(struct omap_hwmod *oh)
+{
+ u32 v;
+ int c = 0;
+
+ /* Write to the SOFTRESET bit */
+ omap_hwmod_softreset(oh);
+
+ /* Enable the module's internal clocks */
+ v = omap_hwmod_read(oh, HDQ_CTRL_STATUS_OFFSET);
+ v |= 1 << HDQ_CTRL_STATUS_CLOCKENABLE_SHIFT;
+ omap_hwmod_write(v, oh, HDQ_CTRL_STATUS_OFFSET);
+
+ /* Poll on RESETDONE bit */
+ omap_test_timeout((omap_hwmod_read(oh,
+ oh->class->sysc->syss_offs)
+ & SYSS_RESETDONE_MASK),
+ MAX_MODULE_SOFTRESET_WAIT, c);
+
+ if (c == MAX_MODULE_SOFTRESET_WAIT)
+ pr_warning("%s: %s: softreset failed (waited %d usec)\n",
+ __func__, oh->name, MAX_MODULE_SOFTRESET_WAIT);
+ else
+ pr_debug("%s: %s: softreset in %d usec\n", __func__,
+ oh->name, c);
+
+ return 0;
+}