1 files changed, 204 insertions, 84 deletions

diff --git a/arch/arm/mach-omap2/omap_hwmod.c b/arch/arm/mach-omap2/omap_hwmod.c
index 70912d1c71e0..c6649472ce0d 100644
--- a/arch/arm/mach-omap2/omap_hwmod.c
+++ b/arch/arm/mach-omap2/omap_hwmod.c
@@ -84,17 +84,16 @@ static u8 inited;
  */
 static int _update_sysc_cache(struct omap_hwmod *oh)
 {
-        if (!oh->sysconfig) {
-                WARN(!oh->sysconfig, "omap_hwmod: %s: cannot read "
-                     "OCP_SYSCONFIG: not defined on hwmod\n", oh->name);
+        if (!oh->class->sysc) {
+                WARN(1, "omap_hwmod: %s: cannot read OCP_SYSCONFIG: not defined on hwmod's class\n", oh->name);
                 return -EINVAL;
         }
 
         /* XXX ensure module interface clock is up */
 
-        oh->_sysc_cache = omap_hwmod_readl(oh, oh->sysconfig->sysc_offs);
+        oh->_sysc_cache = omap_hwmod_readl(oh, oh->class->sysc->sysc_offs);
 
-        if (!(oh->sysconfig->sysc_flags & SYSC_NO_CACHE))
+        if (!(oh->class->sysc->sysc_flags & SYSC_NO_CACHE))
                 oh->_int_flags |= _HWMOD_SYSCONFIG_LOADED;
 
         return 0;
@@ -105,14 +104,13 @@ static int _update_sysc_cache(struct omap_hwmod *oh)
  * @v: OCP_SYSCONFIG value to write
  * @oh: struct omap_hwmod *
  *
- * Write @v into the module OCP_SYSCONFIG register, if it has one.  No
- * return value.
+ * Write @v into the module class' OCP_SYSCONFIG register, if it has
+ * one.  No return value.
  */
 static void _write_sysconfig(u32 v, struct omap_hwmod *oh)
 {
-        if (!oh->sysconfig) {
-                WARN(!oh->sysconfig, "omap_hwmod: %s: cannot write "
-                     "OCP_SYSCONFIG: not defined on hwmod\n", oh->name);
+        if (!oh->class->sysc) {
+                WARN(1, "omap_hwmod: %s: cannot write OCP_SYSCONFIG: not defined on hwmod's class\n", oh->name);
                 return;
         }
 
@@ -120,7 +118,7 @@ static void _write_sysconfig(u32 v, struct omap_hwmod *oh)
 
         if (oh->_sysc_cache != v) {
                 oh->_sysc_cache = v;
-                omap_hwmod_writel(v, oh, oh->sysconfig->sysc_offs);
+                omap_hwmod_writel(v, oh, oh->class->sysc->sysc_offs);
         }
 }
 
@@ -137,12 +135,23 @@ static void _write_sysconfig(u32 v, struct omap_hwmod *oh)
 static int _set_master_standbymode(struct omap_hwmod *oh, u8 standbymode,
                                    u32 *v)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_MIDLEMODE))
+        u32 mstandby_mask;
+        u8 mstandby_shift;
+
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_MIDLEMODE))
+                return -EINVAL;
+
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
                 return -EINVAL;
+        }
 
-        *v &= ~SYSC_MIDLEMODE_MASK;
-        *v |= __ffs(standbymode) << SYSC_MIDLEMODE_SHIFT;
+        mstandby_shift = oh->class->sysc->sysc_fields->midle_shift;
+        mstandby_mask = (0x3 << mstandby_shift);
+
+        *v &= ~mstandby_mask;
+        *v |= __ffs(standbymode) << mstandby_shift;
 
         return 0;
 }
@@ -159,12 +168,23 @@ static int _set_master_standbymode(struct omap_hwmod *oh, u8 standbymode,
  */
 static int _set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode, u32 *v)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_SIDLEMODE))
+        u32 sidle_mask;
+        u8 sidle_shift;
+
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_SIDLEMODE))
                 return -EINVAL;
 
-        *v &= ~SYSC_SIDLEMODE_MASK;
-        *v |= __ffs(idlemode) << SYSC_SIDLEMODE_SHIFT;
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
+                return -EINVAL;
+        }
+
+        sidle_shift = oh->class->sysc->sysc_fields->sidle_shift;
+        sidle_mask = (0x3 << sidle_shift);
+
+        *v &= ~sidle_mask;
+        *v |= __ffs(idlemode) << sidle_shift;
 
         return 0;
 }
@@ -182,12 +202,23 @@ static int _set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode, u32 *v)
  */
 static int _set_clockactivity(struct omap_hwmod *oh, u8 clockact, u32 *v)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_CLOCKACTIVITY))
+        u32 clkact_mask;
+        u8  clkact_shift;
+
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_CLOCKACTIVITY))
                 return -EINVAL;
 
-        *v &= ~SYSC_CLOCKACTIVITY_MASK;
-        *v |= clockact << SYSC_CLOCKACTIVITY_SHIFT;
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
+                return -EINVAL;
+        }
+
+        clkact_shift = oh->class->sysc->sysc_fields->clkact_shift;
+        clkact_mask = (0x3 << clkact_shift);
+
+        *v &= ~clkact_mask;
+        *v |= clockact << clkact_shift;
 
         return 0;
 }
@@ -202,11 +233,20 @@ static int _set_clockactivity(struct omap_hwmod *oh, u8 clockact, u32 *v)
  */
 static int _set_softreset(struct omap_hwmod *oh, u32 *v)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_SOFTRESET))
+        u32 softrst_mask;
+
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET))
+                return -EINVAL;
+
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
                 return -EINVAL;
+        }
 
-        *v |= SYSC_SOFTRESET_MASK;
+        softrst_mask = (0x1 << oh->class->sysc->sysc_fields->srst_shift);
+
+        *v |= softrst_mask;
 
         return 0;
 }
@@ -227,12 +267,23 @@ static int _set_softreset(struct omap_hwmod *oh, u32 *v)
 static int _set_module_autoidle(struct omap_hwmod *oh, u8 autoidle,
                                 u32 *v)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_AUTOIDLE))
+        u32 autoidle_mask;
+        u8 autoidle_shift;
+
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_AUTOIDLE))
                 return -EINVAL;
 
-        *v &= ~SYSC_AUTOIDLE_MASK;
-        *v |= autoidle << SYSC_AUTOIDLE_SHIFT;
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
+                return -EINVAL;
+        }
+
+        autoidle_shift = oh->class->sysc->sysc_fields->autoidle_shift;
+        autoidle_mask = (0x3 << autoidle_shift);
+
+        *v &= ~autoidle_mask;
+        *v |= autoidle << autoidle_shift;
 
         return 0;
 }
@@ -246,14 +297,21 @@ static int _set_module_autoidle(struct omap_hwmod *oh, u8 autoidle,
  */
 static int _enable_wakeup(struct omap_hwmod *oh)
 {
-        u32 v;
+        u32 v, wakeup_mask;
 
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_ENAWAKEUP))
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
                 return -EINVAL;
 
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
+                return -EINVAL;
+        }
+
+        wakeup_mask = (0x1 << oh->class->sysc->sysc_fields->enwkup_shift);
+
         v = oh->_sysc_cache;
-        v |= SYSC_ENAWAKEUP_MASK;
+        v |= wakeup_mask;
         _write_sysconfig(v, oh);
 
         /* XXX test pwrdm_get_wken for this hwmod's subsystem */
@@ -272,14 +330,21 @@ static int _enable_wakeup(struct omap_hwmod *oh)
  */
 static int _disable_wakeup(struct omap_hwmod *oh)
 {
-        u32 v;
+        u32 v, wakeup_mask;
+
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
+                return -EINVAL;
 
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_ENAWAKEUP))
+        if (!oh->class->sysc->sysc_fields) {
+                WARN(1, "omap_hwmod: %s: offset struct for sysconfig not provided in class\n", oh->name);
                 return -EINVAL;
+        }
+
+        wakeup_mask = (0x1 << oh->class->sysc->sysc_fields->enwkup_shift);
 
         v = oh->_sysc_cache;
-        v &= ~SYSC_ENAWAKEUP_MASK;
+        v &= ~wakeup_mask;
         _write_sysconfig(v, oh);
 
         /* XXX test pwrdm_get_wken for this hwmod's subsystem */
@@ -342,18 +407,18 @@ static int _init_main_clk(struct omap_hwmod *oh)
         struct clk *c;
         int ret = 0;
 
-        if (!oh->clkdev_con_id)
+        if (!oh->main_clk)
                 return 0;
 
-        c = clk_get_sys(oh->clkdev_dev_id, oh->clkdev_con_id);
-        WARN(IS_ERR(c), "omap_hwmod: %s: cannot clk_get main_clk %s.%s\n",
-             oh->name, oh->clkdev_dev_id, oh->clkdev_con_id);
+        c = omap_clk_get_by_name(oh->main_clk);
+        WARN(IS_ERR(c), "omap_hwmod: %s: cannot clk_get main_clk %s\n",
+             oh->name, oh->main_clk);
         if (IS_ERR(c))
                 ret = -EINVAL;
         oh->_clk = c;
 
         WARN(!c->clkdm, "omap_hwmod: %s: missing clockdomain for %s.\n",
-             oh->clkdev_con_id, c->name);
+             oh->main_clk, c->name);
 
         return ret;
 }
@@ -376,13 +441,12 @@ static int _init_interface_clks(struct omap_hwmod *oh)
                 return 0;
 
         for (i = 0, os = *oh->slaves; i < oh->slaves_cnt; i++, os++) {
-                if (!os->clkdev_con_id)
+                if (!os->clk)
                         continue;
 
-                c = clk_get_sys(os->clkdev_dev_id, os->clkdev_con_id);
+                c = omap_clk_get_by_name(os->clk);
                 WARN(IS_ERR(c), "omap_hwmod: %s: cannot clk_get "
-                     "interface_clk %s.%s\n", oh->name,
-                     os->clkdev_dev_id, os->clkdev_con_id);
+                     "interface_clk %s\n", oh->name, os->clk);
                 if (IS_ERR(c))
                         ret = -EINVAL;
                 os->_clk = c;
@@ -406,10 +470,9 @@ static int _init_opt_clks(struct omap_hwmod *oh)
         int ret = 0;
 
         for (i = oh->opt_clks_cnt, oc = oh->opt_clks; i > 0; i--, oc++) {
-                c = clk_get_sys(oc->clkdev_dev_id, oc->clkdev_con_id);
+                c = omap_clk_get_by_name(oc->clk);
                 WARN(IS_ERR(c), "omap_hwmod: %s: cannot clk_get opt_clk "
-                     "%s.%s\n", oh->name, oc->clkdev_dev_id,
-                     oc->clkdev_con_id);
+                     "%s\n", oh->name, oc->clk);
                 if (IS_ERR(c))
                         ret = -EINVAL;
                 oc->_clk = c;
@@ -566,27 +629,28 @@ static void __iomem *_find_mpu_rt_base(struct omap_hwmod *oh, u8 index)
  */
 static void _sysc_enable(struct omap_hwmod *oh)
 {
-        u8 idlemode;
+        u8 idlemode, sf;
         u32 v;
 
-        if (!oh->sysconfig)
+        if (!oh->class->sysc)
                 return;
 
         v = oh->_sysc_cache;
+        sf = oh->class->sysc->sysc_flags;
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_SIDLEMODE) {
+        if (sf & SYSC_HAS_SIDLEMODE) {
                 idlemode = (oh->flags & HWMOD_SWSUP_SIDLE) ?
                         HWMOD_IDLEMODE_NO : HWMOD_IDLEMODE_SMART;
                 _set_slave_idlemode(oh, idlemode, &v);
         }
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_MIDLEMODE) {
+        if (sf & SYSC_HAS_MIDLEMODE) {
                 idlemode = (oh->flags & HWMOD_SWSUP_MSTANDBY) ?
                         HWMOD_IDLEMODE_NO : HWMOD_IDLEMODE_SMART;
                 _set_master_standbymode(oh, idlemode, &v);
         }
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_AUTOIDLE) {
+        if (sf & SYSC_HAS_AUTOIDLE) {
                 idlemode = (oh->flags & HWMOD_NO_OCP_AUTOIDLE) ?
                         0 : 1;
                 _set_module_autoidle(oh, idlemode, &v);
@@ -599,9 +663,9 @@ static void _sysc_enable(struct omap_hwmod *oh)
          * calling into this code.  But this must wait until the
          * clock structures are tagged with omap_hwmod entries
          */
-        if (oh->flags & HWMOD_SET_DEFAULT_CLOCKACT &&
-            oh->sysconfig->sysc_flags & SYSC_HAS_CLOCKACTIVITY)
-                _set_clockactivity(oh, oh->sysconfig->clockact, &v);
+        if ((oh->flags & HWMOD_SET_DEFAULT_CLOCKACT) &&
+            (sf & SYSC_HAS_CLOCKACTIVITY))
+                _set_clockactivity(oh, oh->class->sysc->clockact, &v);
 
         _write_sysconfig(v, oh);
 }
@@ -617,21 +681,22 @@ static void _sysc_enable(struct omap_hwmod *oh)
  */
 static void _sysc_idle(struct omap_hwmod *oh)
 {
-        u8 idlemode;
+        u8 idlemode, sf;
         u32 v;
 
-        if (!oh->sysconfig)
+        if (!oh->class->sysc)
                 return;
 
         v = oh->_sysc_cache;
+        sf = oh->class->sysc->sysc_flags;
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_SIDLEMODE) {
+        if (sf & SYSC_HAS_SIDLEMODE) {
                 idlemode = (oh->flags & HWMOD_SWSUP_SIDLE) ?
                         HWMOD_IDLEMODE_FORCE : HWMOD_IDLEMODE_SMART;
                 _set_slave_idlemode(oh, idlemode, &v);
         }
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_MIDLEMODE) {
+        if (sf & SYSC_HAS_MIDLEMODE) {
                 idlemode = (oh->flags & HWMOD_SWSUP_MSTANDBY) ?
                         HWMOD_IDLEMODE_FORCE : HWMOD_IDLEMODE_SMART;
                 _set_master_standbymode(oh, idlemode, &v);
@@ -650,19 +715,21 @@ static void _sysc_idle(struct omap_hwmod *oh)
 static void _sysc_shutdown(struct omap_hwmod *oh)
 {
         u32 v;
+        u8 sf;
 
-        if (!oh->sysconfig)
+        if (!oh->class->sysc)
                 return;
 
         v = oh->_sysc_cache;
+        sf = oh->class->sysc->sysc_flags;
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_SIDLEMODE)
+        if (sf & SYSC_HAS_SIDLEMODE)
                 _set_slave_idlemode(oh, HWMOD_IDLEMODE_FORCE, &v);
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_MIDLEMODE)
+        if (sf & SYSC_HAS_MIDLEMODE)
                 _set_master_standbymode(oh, HWMOD_IDLEMODE_FORCE, &v);
 
-        if (oh->sysconfig->sysc_flags & SYSC_HAS_AUTOIDLE)
+        if (sf & SYSC_HAS_AUTOIDLE)
                 _set_module_autoidle(oh, 1, &v);
 
         _write_sysconfig(v, oh);
@@ -779,9 +846,9 @@ static int _reset(struct omap_hwmod *oh)
         u32 r, v;
         int c = 0;
 
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_SOFTRESET) ||
-            (oh->sysconfig->sysc_flags & SYSS_MISSING))
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_SOFTRESET) ||
+            (oh->class->sysc->sysc_flags & SYSS_MISSING))
                 return -EINVAL;
 
         /* clocks must be on for this operation */
@@ -799,7 +866,7 @@ static int _reset(struct omap_hwmod *oh)
                 return r;
         _write_sysconfig(v, oh);
 
-        omap_test_timeout((omap_hwmod_readl(oh, oh->sysconfig->syss_offs) &
+        omap_test_timeout((omap_hwmod_readl(oh, oh->class->sysc->syss_offs) &
                            SYSS_RESETDONE_MASK),
                           MAX_MODULE_RESET_WAIT, c);
 
@@ -845,7 +912,7 @@ static int _enable(struct omap_hwmod *oh)
         _add_initiator_dep(oh, mpu_oh);
         _enable_clocks(oh);
 
-        if (oh->sysconfig) {
+        if (oh->class->sysc) {
                 if (!(oh->_int_flags & _HWMOD_SYSCONFIG_LOADED))
                         _update_sysc_cache(oh);
                 _sysc_enable(oh);
@@ -876,7 +943,7 @@ static int _idle(struct omap_hwmod *oh)
 
         pr_debug("omap_hwmod: %s: idling\n", oh->name);
 
-        if (oh->sysconfig)
+        if (oh->class->sysc)
                 _sysc_idle(oh);
         _del_initiator_dep(oh, mpu_oh);
         _disable_clocks(oh);
@@ -906,7 +973,7 @@ static int _shutdown(struct omap_hwmod *oh)
 
         pr_debug("omap_hwmod: %s: disabling\n", oh->name);
 
-        if (oh->sysconfig)
+        if (oh->class->sysc)
                 _sysc_shutdown(oh);
         _del_initiator_dep(oh, mpu_oh);
         /* XXX what about the other system initiators here? DMA, tesla, d2d */
@@ -966,7 +1033,7 @@ static int _setup(struct omap_hwmod *oh)
                  * _enable() function should be split to avoid the
                  * rewrite of the OCP_SYSCONFIG register.
                  */
-                if (oh->sysconfig) {
+                if (oh->class->sysc) {
                         _update_sysc_cache(oh);
                         _sysc_enable(oh);
                 }
@@ -1013,9 +1080,12 @@ int omap_hwmod_set_slave_idlemode(struct omap_hwmod *oh, u8 idlemode)
  * omap_hwmod_register - register a struct omap_hwmod
  * @oh: struct omap_hwmod *
  *
- * Registers the omap_hwmod @oh.  Returns -EEXIST if an omap_hwmod already
- * has been registered by the same name; -EINVAL if the omap_hwmod is in the
- * wrong state, or 0 on success.
+ * Registers the omap_hwmod @oh.  Returns -EEXIST if an omap_hwmod
+ * already has been registered by the same name; -EINVAL if the
+ * omap_hwmod is in the wrong state, if @oh is NULL, if the
+ * omap_hwmod's class field is NULL; if the omap_hwmod is missing a
+ * name, or if the omap_hwmod's class is missing a name; or 0 upon
+ * success.
  *
  * XXX The data should be copied into bootmem, so the original data
  * should be marked __initdata and freed after init.  This would allow
@@ -1027,7 +1097,8 @@ int omap_hwmod_register(struct omap_hwmod *oh)
 {
         int ret, ms_id;
 
-        if (!oh || (oh->_state != _HWMOD_STATE_UNKNOWN))
+        if (!oh || !oh->name || !oh->class || !oh->class->name ||
+            (oh->_state != _HWMOD_STATE_UNKNOWN))
                 return -EINVAL;
 
         mutex_lock(&omap_hwmod_mutex);
@@ -1300,7 +1371,7 @@ void omap_hwmod_ocp_barrier(struct omap_hwmod *oh)
 {
         BUG_ON(!oh);
 
-        if (!oh->sysconfig || !oh->sysconfig->sysc_flags) {
+        if (!oh->class->sysc || !oh->class->sysc->sysc_flags) {
                 WARN(1, "omap_device: %s: OCP barrier impossible due to "
                       "device configuration\n", oh->name);
                 return;
@@ -1310,7 +1381,7 @@ void omap_hwmod_ocp_barrier(struct omap_hwmod *oh)
          * Forces posted writes to complete on the OCP thread handling
          * register writes
          */
-        omap_hwmod_readl(oh, oh->sysconfig->sysc_offs);
+        omap_hwmod_readl(oh, oh->class->sysc->sysc_offs);
 }
 
 /**
@@ -1503,8 +1574,8 @@ int omap_hwmod_del_initiator_dep(struct omap_hwmod *oh,
  */
 int omap_hwmod_enable_wakeup(struct omap_hwmod *oh)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_ENAWAKEUP))
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
                 return -EINVAL;
 
         mutex_lock(&omap_hwmod_mutex);
@@ -1528,8 +1599,8 @@ int omap_hwmod_enable_wakeup(struct omap_hwmod *oh)
  */
 int omap_hwmod_disable_wakeup(struct omap_hwmod *oh)
 {
-        if (!oh->sysconfig ||
-            !(oh->sysconfig->sysc_flags & SYSC_HAS_ENAWAKEUP))
+        if (!oh->class->sysc ||
+            !(oh->class->sysc->sysc_flags & SYSC_HAS_ENAWAKEUP))
                 return -EINVAL;
 
         mutex_lock(&omap_hwmod_mutex);
@@ -1538,3 +1609,52 @@ int omap_hwmod_disable_wakeup(struct omap_hwmod *oh)
 
         return 0;
 }
+
+/**
+ * omap_hwmod_for_each_by_class - call @fn for each hwmod of class @classname
+ * @classname: struct omap_hwmod_class name to search for
+ * @fn: callback function pointer to call for each hwmod in class @classname
+ * @user: arbitrary context data to pass to the callback function
+ *
+ * For each omap_hwmod of class @classname, call @fn.  Takes
+ * omap_hwmod_mutex to prevent the hwmod list from changing during the
+ * iteration.  If the callback function returns something other than
+ * zero, the iterator is terminated, and the callback function's return
+ * value is passed back to the caller.  Returns 0 upon success, -EINVAL
+ * if @classname or @fn are NULL, or passes back the error code from @fn.
+ */
+int omap_hwmod_for_each_by_class(const char *classname,
+                                 int (*fn)(struct omap_hwmod *oh,
+                                           void *user),
+                                 void *user)
+{
+        struct omap_hwmod *temp_oh;
+        int ret = 0;
+
+        if (!classname || !fn)
+                return -EINVAL;
+
+        pr_debug("omap_hwmod: %s: looking for modules of class %s\n",
+                 __func__, classname);
+
+        mutex_lock(&omap_hwmod_mutex);
+
+        list_for_each_entry(temp_oh, &omap_hwmod_list, node) {
+                if (!strcmp(temp_oh->class->name, classname)) {
+                        pr_debug("omap_hwmod: %s: %s: calling callback fn\n",
+                                 __func__, temp_oh->name);
+                        ret = (*fn)(temp_oh, user);
+                        if (ret)
+                                break;
+                }
+        }
+
+        mutex_unlock(&omap_hwmod_mutex);
+
+        if (ret)
+                pr_debug("omap_hwmod: %s: iterator terminated early: %d\n",
+                         __func__, ret);
+
+        return ret;
+}
+