[PATCH 2/8] of: dma: Move range size workaround to of_dma_get_range()

Sricharan R
2016-08-08T22:49:04Z

From: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Invalid dma-ranges values should be worked around when retrieving the
DMA range in of_dma_get_range(), not by all callers of the function.
This isn't much of a problem now that we have a single caller, but that
situation will change when moving DMA configuration to device probe
time.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
drivers/of/address.c | 20 ++++++++++++++++++--
drivers/of/device.c | 15 ---------------
2 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/drivers/of/address.c b/drivers/of/address.c
index 0a553c0..8cb1aee 100644
--- a/drivers/of/address.c
+++ b/drivers/of/address.c
@@ -817,8 +817,8 @@ EXPORT_SYMBOL(of_io_request_and_map);
* CPU addr (phys_addr_t) : pna cells
* size : nsize cells
*
- * It returns -ENODEV if "dma-ranges" property was not found
- * for this device in DT.
+ * Return 0 on success, -ENODEV if the "dma-ranges" property was not found for
+ * this device in DT, or -EINVAL if the CPU address or size is invalid.
*/
int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *size)
{
@@ -879,6 +879,22 @@ int of_dma_get_range(struct device_node *np, u64 *dma_addr, u64 *paddr, u64 *siz
*dma_addr = dmaaddr;

*size = of_read_number(ranges + naddr + pna, nsize);
+ /*
+ * DT nodes sometimes incorrectly set the size as a mask. Work around
+ * those incorrect DT by computing the size as mask + 1.
+ */
+ if (*size & 1) {
+ pr_warn("%s: size 0x%llx for dma-range in node(%s) set as mask\n",
+ __func__, *size, np->full_name);
+ *size = *size + 1;
+ }
+
+ if (!*size) {
+ pr_err("%s: invalid size zero for dma-range in node(%s)\n",
+ __func__, np->full_name);
+ ret = -EINVAL;
+ goto out;
+ }

pr_debug("dma_addr(%llx) cpu_addr(%llx) size(%llx)\n",
*dma_addr, *paddr, *size);
diff --git a/drivers/of/device.c b/drivers/of/device.c
index fd5cfad..d9898d9 100644
--- a/drivers/of/device.c
+++ b/drivers/of/device.c
@@ -110,21 +110,6 @@ void of_dma_configure(struct device *dev, struct device_node *np)
size = dev->coherent_dma_mask + 1;
} else {
offset = PFN_DOWN(paddr - dma_addr);
-
- /*
- * Add a work around to treat the size as mask + 1 in case
- * it is defined in DT as a mask.
- */
- if (size & 1) {
- dev_warn(dev, "Invalid size 0x%llx for dma-range\n",
- size);
- size = size + 1;
- }
-
- if (!size) {
- dev_err(dev, "Adjusted size 0x%llx invalid\n", size);
- return;
- }
dev_dbg(dev, "dma_pfn_offset(%#08lx)\n", offset);
}

--
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