[Patch V2] soc/tegra: fuse: Add fuse clock check in tegra_fuse_readl

[Nagarjuna Kristam <nkristam@nvidia.com>]

tegra_fuse_readl() can be called from drivers at any time. If this API is
called before tegra_fuse_probe(), we end up enabling clock before it is
registered. Add check for fuse clock in tegra_fuse_readl() and return
corresponding error if any.

Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com>
---
V2:
	- Added Null and other error checks for fuse->clk.
---
 drivers/soc/tegra/fuse/fuse-tegra.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c
index 3eb44e6..58996c6 100644
--- a/drivers/soc/tegra/fuse/fuse-tegra.c
+++ b/drivers/soc/tegra/fuse/fuse-tegra.c
@@ -186,9 +186,12 @@ u32 __init tegra_fuse_read_early(unsigned int offset)
 
 int tegra_fuse_readl(unsigned long offset, u32 *value)
 {
-	if (!fuse->read)
+	if (!fuse->read || !fuse->clk)
 		return -EPROBE_DEFER;
 
+	if (IS_ERR(fuse->clk))
+		return PTR_ERR(fuse->clk);
+
 	*value = fuse->read(fuse, offset);
 
 	return 0;
-- 
2.7.4