Merge branch 'topic/of' into for-linus

Conflicts:
	include/linux/dmaengine.h

Signed-off-by: Vinod Koul <vinod.koul@intel.com>

diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 1b2df59..93f7992 100644 (file)
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -560,7 +560,7 @@ EXPORT_SYMBOL_GPL(__dma_request_channel);
  * @dev:       pointer to client device structure
  * @name:      slave channel name
  */
-struct dma_chan *dma_request_slave_channel(struct device *dev, char *name)
+struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name)
 {
        /* If device-tree is present get slave info from here */
        if (dev->of_node)

diff --git a/drivers/dma/of-dma.c b/drivers/dma/of-dma.c
index 69d04d2..7aa0864 100644 (file)
--- a/drivers/dma/of-dma.c
+++ b/drivers/dma/of-dma.c
@@ -13,43 +13,31 @@
 #include <linux/device.h>
 #include <linux/err.h>
 #include <linux/module.h>
-#include <linux/rculist.h>
+#include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_dma.h>
 
 static LIST_HEAD(of_dma_list);
-static DEFINE_SPINLOCK(of_dma_lock);
+static DEFINE_MUTEX(of_dma_lock);
 
 /**
- * of_dma_get_controller - Get a DMA controller in DT DMA helpers list
+ * of_dma_find_controller - Get a DMA controller in DT DMA helpers list
  * @dma_spec:  pointer to DMA specifier as found in the device tree
  *
  * Finds a DMA controller with matching device node and number for dma cells
- * in a list of registered DMA controllers. If a match is found the use_count
- * variable is increased and a valid pointer to the DMA data stored is retuned.
- * A NULL pointer is returned if no match is found.
+ * in a list of registered DMA controllers. If a match is found a valid pointer
+ * to the DMA data stored is retuned. A NULL pointer is returned if no match is
+ * found.
  */
-static struct of_dma *of_dma_get_controller(struct of_phandle_args *dma_spec)
+static struct of_dma *of_dma_find_controller(struct of_phandle_args *dma_spec)
 {
        struct of_dma *ofdma;
 
-       spin_lock(&of_dma_lock);
-
-       if (list_empty(&of_dma_list)) {
-               spin_unlock(&of_dma_lock);
-               return NULL;
-       }
-
        list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers)
                if ((ofdma->of_node == dma_spec->np) &&
-                   (ofdma->of_dma_nbcells == dma_spec->args_count)) {
-                       ofdma->use_count++;
-                       spin_unlock(&of_dma_lock);
+                   (ofdma->of_dma_nbcells == dma_spec->args_count))
                        return ofdma;
-               }
-
-       spin_unlock(&of_dma_lock);
 
        pr_debug("%s: can't find DMA controller %s\n", __func__,
                 dma_spec->np->full_name);
@@ -58,22 +46,6 @@ static struct of_dma *of_dma_get_controller(struct of_phandle_args *dma_spec)
 }
 
 /**
- * of_dma_put_controller - Decrement use count for a registered DMA controller
- * @of_dma:    pointer to DMA controller data
- *
- * Decrements the use_count variable in the DMA data structure. This function
- * should be called only when a valid pointer is returned from
- * of_dma_get_controller() and no further accesses to data referenced by that
- * pointer are needed.
- */
-static void of_dma_put_controller(struct of_dma *ofdma)
-{
-       spin_lock(&of_dma_lock);
-       ofdma->use_count--;
-       spin_unlock(&of_dma_lock);
-}
-
-/**
  * of_dma_controller_register - Register a DMA controller to DT DMA helpers
  * @np:                        device node of DMA controller
  * @of_dma_xlate:      translation function which converts a phandle
@@ -93,6 +65,7 @@ int of_dma_controller_register(struct device_node *np,
 {
        struct of_dma   *ofdma;
        int             nbcells;
+       const __be32    *prop;
 
        if (!np || !of_dma_xlate) {
                pr_err("%s: not enough information provided\n", __func__);
@@ -103,8 +76,11 @@ int of_dma_controller_register(struct device_node *np,
        if (!ofdma)
                return -ENOMEM;
 
-       nbcells = be32_to_cpup(of_get_property(np, "#dma-cells", NULL));
-       if (!nbcells) {
+       prop = of_get_property(np, "#dma-cells", NULL);
+       if (prop)
+               nbcells = be32_to_cpup(prop);
+
+       if (!prop || !nbcells) {
                pr_err("%s: #dma-cells property is missing or invalid\n",
                       __func__);
                kfree(ofdma);
@@ -115,12 +91,11 @@ int of_dma_controller_register(struct device_node *np,
        ofdma->of_dma_nbcells = nbcells;
        ofdma->of_dma_xlate = of_dma_xlate;
        ofdma->of_dma_data = data;
-       ofdma->use_count = 0;
 
        /* Now queue of_dma controller structure in list */
-       spin_lock(&of_dma_lock);
+       mutex_lock(&of_dma_lock);
        list_add_tail(&ofdma->of_dma_controllers, &of_dma_list);
-       spin_unlock(&of_dma_lock);
+       mutex_unlock(&of_dma_lock);
 
        return 0;
 }
@@ -132,32 +107,20 @@ EXPORT_SYMBOL_GPL(of_dma_controller_register);
  *
  * Memory allocated by of_dma_controller_register() is freed here.
  */
-int of_dma_controller_free(struct device_node *np)
+void of_dma_controller_free(struct device_node *np)
 {
        struct of_dma *ofdma;
 
-       spin_lock(&of_dma_lock);
-
-       if (list_empty(&of_dma_list)) {
-               spin_unlock(&of_dma_lock);
-               return -ENODEV;
-       }
+       mutex_lock(&of_dma_lock);
 
        list_for_each_entry(ofdma, &of_dma_list, of_dma_controllers)
                if (ofdma->of_node == np) {
-                       if (ofdma->use_count) {
-                               spin_unlock(&of_dma_lock);
-                               return -EBUSY;
-                       }
-
                        list_del(&ofdma->of_dma_controllers);
-                       spin_unlock(&of_dma_lock);
                        kfree(ofdma);
-                       return 0;
+                       break;
                }
 
-       spin_unlock(&of_dma_lock);
-       return -ENODEV;
+       mutex_unlock(&of_dma_lock);
 }
 EXPORT_SYMBOL_GPL(of_dma_controller_free);
 
@@ -172,8 +135,8 @@ EXPORT_SYMBOL_GPL(of_dma_controller_free);
  * specifiers, matches the name provided. Returns 0 if the name matches and
  * a valid pointer to the DMA specifier is found. Otherwise returns -ENODEV.
  */
-static int of_dma_match_channel(struct device_node *np, char *name, int index,
-                               struct of_phandle_args *dma_spec)
+static int of_dma_match_channel(struct device_node *np, const char *name,
+                               int index, struct of_phandle_args *dma_spec)
 {
        const char *s;
 
@@ -198,7 +161,7 @@ static int of_dma_match_channel(struct device_node *np, char *name, int index,
  * Returns pointer to appropriate dma channel on success or NULL on error.
  */
 struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
-                                             char *name)
+                                             const char *name)
 {
        struct of_phandle_args  dma_spec;
        struct of_dma           *ofdma;
@@ -220,14 +183,15 @@ struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
                if (of_dma_match_channel(np, name, i, &dma_spec))
                        continue;
 
-               ofdma = of_dma_get_controller(&dma_spec);
-
-               if (!ofdma)
-                       continue;
+               mutex_lock(&of_dma_lock);
+               ofdma = of_dma_find_controller(&dma_spec);
 
-               chan = ofdma->of_dma_xlate(&dma_spec, ofdma);
+               if (ofdma)
+                       chan = ofdma->of_dma_xlate(&dma_spec, ofdma);
+               else
+                       chan = NULL;
 
-               of_dma_put_controller(ofdma);
+               mutex_unlock(&of_dma_lock);
 
                of_node_put(dma_spec.np);
 

diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index dd6d21b..96d3e4a 100644 (file)
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -969,7 +969,7 @@ enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx);
 void dma_issue_pending_all(void);
 struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
                                        dma_filter_fn fn, void *fn_param);
-struct dma_chan *dma_request_slave_channel(struct device *dev, char *name);
+struct dma_chan *dma_request_slave_channel(struct device *dev, const char *name);
 void dma_release_channel(struct dma_chan *chan);
 #else
 static inline enum dma_status dma_wait_for_async_tx(struct dma_async_tx_descriptor *tx)
@@ -985,7 +985,7 @@ static inline struct dma_chan *__dma_request_channel(const dma_cap_mask_t *mask,
        return NULL;
 }
 static inline struct dma_chan *dma_request_slave_channel(struct device *dev,
-                                                        char *name)
+                                                        const char *name)
 {
        return NULL;
 }

diff --git a/include/linux/of_dma.h b/include/linux/of_dma.h
index d15073e..364dda7 100644 (file)
--- a/include/linux/of_dma.h
+++ b/include/linux/of_dma.h
@@ -25,7 +25,6 @@ struct of_dma {
        struct dma_chan         *(*of_dma_xlate)
                                (struct of_phandle_args *, struct of_dma *);
        void                    *of_dma_data;
-       int                     use_count;
 };
 
 struct of_dma_filter_info {
@@ -38,9 +37,9 @@ extern int of_dma_controller_register(struct device_node *np,
                struct dma_chan *(*of_dma_xlate)
                (struct of_phandle_args *, struct of_dma *),
                void *data);
-extern int of_dma_controller_free(struct device_node *np);
+extern void of_dma_controller_free(struct device_node *np);
 extern struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
-                                                    char *name);
+                                                    const char *name);
 extern struct dma_chan *of_dma_simple_xlate(struct of_phandle_args *dma_spec,
                struct of_dma *ofdma);
 #else
@@ -52,13 +51,12 @@ static inline int of_dma_controller_register(struct device_node *np,
        return -ENODEV;
 }
 
-static inline int of_dma_controller_free(struct device_node *np)
+static inline void of_dma_controller_free(struct device_node *np)
 {
-       return -ENODEV;
 }
 
 static inline struct dma_chan *of_dma_request_slave_channel(struct device_node *np,
-                                                    char *name)
+                                                    const char *name)
 {
        return NULL;
 }