soc: qcom: Make qcom_smem_get() return a pointer

Passing a void ** almost always requires a cast at the call site.
Instead of littering the code with casts every time this function
is called, have qcom_smem_get() return a void pointer to the
location of the smem item. This frees the caller from having to
cast the pointer.

Cc: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Signed-off-by: Andy Gross <agross@codeaurora.org>

3 files changed, 48 insertions, 56 deletions

diff --git a/drivers/soc/qcom/smd.c b/drivers/soc/qcom/smd.c
index d883c16d1775..beaea1d5169f 100644
--- a/drivers/soc/qcom/smd.c
+++ b/drivers/soc/qcom/smd.c
@@ -989,10 +989,11 @@ static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *ed
         spin_lock_init(&channel->recv_lock);
         init_waitqueue_head(&channel->fblockread_event);
 
-        ret = qcom_smem_get(edge->remote_pid, smem_info_item, (void **)&info,
-                            &info_size);
-        if (ret)
+        info = qcom_smem_get(edge->remote_pid, smem_info_item, &info_size);
+        if (IS_ERR(info)) {
+                ret = PTR_ERR(info);
                 goto free_name_and_channel;
+        }
 
         /*
          * Use the size of the item to figure out which channel info struct to
@@ -1011,10 +1012,11 @@ static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *ed
                 goto free_name_and_channel;
         }
 
-        ret = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_base,
-                            &fifo_size);
-        if (ret)
+        fifo_base = qcom_smem_get(edge->remote_pid, smem_fifo_item, &fifo_size);
+        if (IS_ERR(fifo_base)) {
+                ret =  PTR_ERR(fifo_base);
                 goto free_name_and_channel;
+        }
 
         /* The channel consist of a rx and tx fifo of equal size */
         fifo_size /= 2;
@@ -1051,16 +1053,13 @@ static void qcom_discover_channels(struct qcom_smd_edge *edge)
         unsigned long flags;
         unsigned fifo_id;
         unsigned info_id;
-        int ret;
         int tbl;
         int i;
 
         for (tbl = 0; tbl < SMD_ALLOC_TBL_COUNT; tbl++) {
-                ret = qcom_smem_get(edge->remote_pid,
-                                    smem_items[tbl].alloc_tbl_id,
-                                    (void **)&alloc_tbl,
-                                    NULL);
-                if (ret < 0)
+                alloc_tbl = qcom_smem_get(edge->remote_pid,
+                                    smem_items[tbl].alloc_tbl_id, NULL);
+                if (IS_ERR(alloc_tbl))
                         continue;
 
                 for (i = 0; i < SMD_ALLOC_TBL_SIZE; i++) {
@@ -1238,11 +1237,12 @@ static int qcom_smd_probe(struct platform_device *pdev)
         int num_edges;
         int ret;
         int i = 0;
+        void *p;
 
         /* Wait for smem */
-        ret = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL, NULL);
-        if (ret == -EPROBE_DEFER)
-                return ret;
+        p = qcom_smem_get(QCOM_SMEM_HOST_ANY, smem_items[0].alloc_tbl_id, NULL);
+        if (PTR_ERR(p) == -EPROBE_DEFER)
+                return PTR_ERR(p);
 
         num_edges = of_get_available_child_count(pdev->dev.of_node);
         array_size = sizeof(*smd) + num_edges * sizeof(struct qcom_smd_edge);
diff --git a/drivers/soc/qcom/smem.c b/drivers/soc/qcom/smem.c
index f402a606eb7d..e6d0dae63845 100644
--- a/drivers/soc/qcom/smem.c
+++ b/drivers/soc/qcom/smem.c
@@ -378,10 +378,9 @@ int qcom_smem_alloc(unsigned host, unsigned item, size_t size)
 }
 EXPORT_SYMBOL(qcom_smem_alloc);
 
-static int qcom_smem_get_global(struct qcom_smem *smem,
-                                unsigned item,
-                                void **ptr,
-                                size_t *size)
+static void *qcom_smem_get_global(struct qcom_smem *smem,
+                                  unsigned item,
+                                  size_t *size)
 {
         struct smem_header *header;
         struct smem_region *area;
@@ -390,36 +389,32 @@ static int qcom_smem_get_global(struct qcom_smem *smem,
         unsigned i;
 
         if (WARN_ON(item >= SMEM_ITEM_COUNT))
-                return -EINVAL;
+                return ERR_PTR(-EINVAL);
 
         header = smem->regions[0].virt_base;
         entry = &header->toc[item];
         if (!entry->allocated)
-                return -ENXIO;
+                return ERR_PTR(-ENXIO);
 
-        if (ptr != NULL) {
-                aux_base = entry->aux_base & AUX_BASE_MASK;
+        aux_base = entry->aux_base & AUX_BASE_MASK;
 
-                for (i = 0; i < smem->num_regions; i++) {
-                        area = &smem->regions[i];
+        for (i = 0; i < smem->num_regions; i++) {
+                area = &smem->regions[i];
 
-                        if (area->aux_base == aux_base || !aux_base) {
-                                *ptr = area->virt_base + entry->offset;
-                                break;
-                        }
+                if (area->aux_base == aux_base || !aux_base) {
+                        if (size != NULL)
+                                *size = entry->size;
+                        return area->virt_base + entry->offset;
                 }
         }
-        if (size != NULL)
-                *size = entry->size;
 
-        return 0;
+        return ERR_PTR(-ENOENT);
 }
 
-static int qcom_smem_get_private(struct qcom_smem *smem,
-                                 unsigned host,
-                                 unsigned item,
-                                 void **ptr,
-                                 size_t *size)
+static void *qcom_smem_get_private(struct qcom_smem *smem,
+                                   unsigned host,
+                                   unsigned item,
+                                   size_t *size)
 {
         struct smem_partition_header *phdr;
         struct smem_private_entry *hdr;
@@ -435,55 +430,54 @@ static int qcom_smem_get_private(struct qcom_smem *smem,
                         dev_err(smem->dev,
                                 "Found invalid canary in host %d partition\n",
                                 host);
-                        return -EINVAL;
+                        return ERR_PTR(-EINVAL);
                 }
 
                 if (hdr->item == item) {
-                        if (ptr != NULL)
-                                *ptr = p + sizeof(*hdr) + hdr->padding_hdr;
-
                         if (size != NULL)
                                 *size = hdr->size - hdr->padding_data;
 
-                        return 0;
+                        return p + sizeof(*hdr) + hdr->padding_hdr;
                 }
 
                 p += sizeof(*hdr) + hdr->padding_hdr + hdr->size;
         }
 
-        return -ENOENT;
+        return ERR_PTR(-ENOENT);
 }
 
 /**
  * qcom_smem_get() - resolve ptr of size of a smem item
  * @host:       the remote processor, or -1
  * @item:       smem item handle
- * @ptr:        pointer to be filled out with address of the item
  * @size:       pointer to be filled out with size of the item
  *
- * Looks up pointer and size of a smem item.
+ * Looks up smem item and returns pointer to it. Size of smem
+ * item is returned in @size.
  */
-int qcom_smem_get(unsigned host, unsigned item, void **ptr, size_t *size)
+void *qcom_smem_get(unsigned host, unsigned item, size_t *size)
 {
         unsigned long flags;
         int ret;
+        void *ptr = ERR_PTR(-EPROBE_DEFER);
 
         if (!__smem)
-                return -EPROBE_DEFER;
+                return ptr;
 
         ret = hwspin_lock_timeout_irqsave(__smem->hwlock,
                                           HWSPINLOCK_TIMEOUT,
                                           &flags);
         if (ret)
-                return ret;
+                return ERR_PTR(ret);
 
         if (host < SMEM_HOST_COUNT && __smem->partitions[host])
-                ret = qcom_smem_get_private(__smem, host, item, ptr, size);
+                ptr = qcom_smem_get_private(__smem, host, item, size);
         else
-                ret = qcom_smem_get_global(__smem, item, ptr, size);
+                ptr = qcom_smem_get_global(__smem, item, size);
 
         hwspin_unlock_irqrestore(__smem->hwlock, &flags);
-        return ret;
+
+        return ptr;
 
 }
 EXPORT_SYMBOL(qcom_smem_get);
@@ -520,11 +514,9 @@ static int qcom_smem_get_sbl_version(struct qcom_smem *smem)
 {
         unsigned *versions;
         size_t size;
-        int ret;
 
-        ret = qcom_smem_get_global(smem, SMEM_ITEM_VERSION,
-                                   (void **)&versions, &size);
-        if (ret < 0) {
+        versions = qcom_smem_get_global(smem, SMEM_ITEM_VERSION, &size);
+        if (IS_ERR(versions)) {
                 dev_err(smem->dev, "Unable to read the version item\n");
                 return -ENOENT;
         }
diff --git a/include/linux/soc/qcom/smem.h b/include/linux/soc/qcom/smem.h
index bc9630d3aced..785e196ee2ca 100644
--- a/include/linux/soc/qcom/smem.h
+++ b/include/linux/soc/qcom/smem.h
@@ -4,7 +4,7 @@
 #define QCOM_SMEM_HOST_ANY -1
 
 int qcom_smem_alloc(unsigned host, unsigned item, size_t size);
-int qcom_smem_get(unsigned host, unsigned item, void **ptr, size_t *size);
+void *qcom_smem_get(unsigned host, unsigned item, size_t *size);
 
 int qcom_smem_get_free_space(unsigned host);