[PATCH -next] mailbox: Fix NULL vs IS_ERR() check in zynqmp_ipi_mbox_probe()

[Wei Yongjun]

In case of error, the function devm_ioremap() returns NULL pointer not
ERR_PTR(). The IS_ERR() test in the return value check should be
replaced with NULL test.

Fixes: 4981b82ba2ff ("mailbox: ZynqMP IPI mailbox controller")
Signed-off-by: Wei Yongjun <weiyongj...@huawei.com>
---
 drivers/mailbox/zynqmp-ipi-mailbox.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/mailbox/zynqmp-ipi-mailbox.c 
b/drivers/mailbox/zynqmp-ipi-mailbox.c
index 86887c9a349a..f9cc674ba9b7 100644
--- a/drivers/mailbox/zynqmp-ipi-mailbox.c
+++ b/drivers/mailbox/zynqmp-ipi-mailbox.c
@@ -504,10 +504,9 @@ static int zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox 
*ipi_mbox,
                mchan->req_buf_size = resource_size(&res);
                mchan->req_buf = devm_ioremap(mdev, res.start,
                                              mchan->req_buf_size);
-               if (IS_ERR(mchan->req_buf)) {
+               if (!mchan->req_buf) {
                        dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
-                       ret = PTR_ERR(mchan->req_buf);
-                       return ret;
+                       return -ENOMEM;
                }
        } else if (ret != -ENODEV) {
                dev_err(mdev, "Unmatched resource %s, %d.\n", name, ret);
@@ -520,10 +519,9 @@ static int zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox 
*ipi_mbox,
                mchan->resp_buf_size = resource_size(&res);
                mchan->resp_buf = devm_ioremap(mdev, res.start,
                                               mchan->resp_buf_size);
-               if (IS_ERR(mchan->resp_buf)) {
+               if (!mchan->resp_buf) {
                        dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
-                       ret = PTR_ERR(mchan->resp_buf);
-                       return ret;
+                       return -ENOMEM;
                }
        } else if (ret != -ENODEV) {
                dev_err(mdev, "Unmatched resource %s.\n", name);
@@ -543,10 +541,9 @@ static int zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox 
*ipi_mbox,
                mchan->req_buf_size = resource_size(&res);
                mchan->req_buf = devm_ioremap(mdev, res.start,
                                              mchan->req_buf_size);
-               if (IS_ERR(mchan->req_buf)) {
+               if (!mchan->req_buf) {
                        dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
-                       ret = PTR_ERR(mchan->req_buf);
-                       return ret;
+                       return -ENOMEM;
                }
        } else if (ret != -ENODEV) {
                dev_err(mdev, "Unmatched resource %s.\n", name);
@@ -559,10 +556,9 @@ static int zynqmp_ipi_mbox_probe(struct zynqmp_ipi_mbox 
*ipi_mbox,
                mchan->resp_buf_size = resource_size(&res);
                mchan->resp_buf = devm_ioremap(mdev, res.start,
                                               mchan->resp_buf_size);
-               if (IS_ERR(mchan->resp_buf)) {
+               if (!mchan->resp_buf) {
                        dev_err(mdev, "Unable to map IPI buffer I/O memory\n");
-                       ret = PTR_ERR(mchan->resp_buf);
-                       return ret;
+                       return -ENOMEM;
                }
        } else if (ret != -ENODEV) {
                dev_err(mdev, "Unmatched resource %s.\n", name);