drivers: clk: Handle gracefully NULL pointers
Prepare the way for a managed CLK API by handling NULL pointers without
crashing nor failing.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
diff --git a/drivers/clk/clk-uclass.c b/drivers/clk/clk-uclass.c
index bf1adc0..82a62c0 100644
--- a/drivers/clk/clk-uclass.c
+++ b/drivers/clk/clk-uclass.c
@@ -349,9 +349,12 @@
int clk_request(struct udevice *dev, struct clk *clk)
{
- const struct clk_ops *ops = clk_dev_ops(dev);
+ const struct clk_ops *ops;
debug("%s(dev=%p, clk=%p)\n", __func__, dev, clk);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(dev);
clk->dev = dev;
@@ -363,9 +366,12 @@
int clk_free(struct clk *clk)
{
- const struct clk_ops *ops = clk_dev_ops(clk->dev);
+ const struct clk_ops *ops;
debug("%s(clk=%p)\n", __func__, clk);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(clk->dev);
if (!ops->free)
return 0;
@@ -375,9 +381,12 @@
ulong clk_get_rate(struct clk *clk)
{
- const struct clk_ops *ops = clk_dev_ops(clk->dev);
+ const struct clk_ops *ops;
debug("%s(clk=%p)\n", __func__, clk);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(clk->dev);
if (!ops->get_rate)
return -ENOSYS;
@@ -391,6 +400,8 @@
struct clk *pclk;
debug("%s(clk=%p)\n", __func__, clk);
+ if (!clk)
+ return NULL;
pdev = dev_get_parent(clk->dev);
pclk = dev_get_clk_ptr(pdev);
@@ -406,6 +417,8 @@
struct clk *pclk;
debug("%s(clk=%p)\n", __func__, clk);
+ if (!clk)
+ return 0;
pclk = clk_get_parent(clk);
if (IS_ERR(pclk))
@@ -424,9 +437,12 @@
ulong clk_set_rate(struct clk *clk, ulong rate)
{
- const struct clk_ops *ops = clk_dev_ops(clk->dev);
+ const struct clk_ops *ops;
debug("%s(clk=%p, rate=%lu)\n", __func__, clk, rate);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(clk->dev);
if (!ops->set_rate)
return -ENOSYS;
@@ -436,9 +452,12 @@
int clk_set_parent(struct clk *clk, struct clk *parent)
{
- const struct clk_ops *ops = clk_dev_ops(clk->dev);
+ const struct clk_ops *ops;
debug("%s(clk=%p, parent=%p)\n", __func__, clk, parent);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(clk->dev);
if (!ops->set_parent)
return -ENOSYS;
@@ -448,11 +467,14 @@
int clk_enable(struct clk *clk)
{
- const struct clk_ops *ops = clk_dev_ops(clk->dev);
+ const struct clk_ops *ops;
struct clk *clkp = NULL;
int ret;
debug("%s(clk=%p)\n", __func__, clk);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(clk->dev);
if (CONFIG_IS_ENABLED(CLK_CCF)) {
/* Take id 0 as a non-valid clk, such as dummy */
@@ -505,11 +527,14 @@
int clk_disable(struct clk *clk)
{
- const struct clk_ops *ops = clk_dev_ops(clk->dev);
+ const struct clk_ops *ops;
struct clk *clkp = NULL;
int ret;
debug("%s(clk=%p)\n", __func__, clk);
+ if (!clk)
+ return 0;
+ ops = clk_dev_ops(clk->dev);
if (CONFIG_IS_ENABLED(CLK_CCF)) {
if (clk->id && !clk_get_by_id(clk->id, &clkp)) {
@@ -589,6 +614,10 @@
if (p == q)
return true;
+ /* trivial case #2: on the clk pointer is NULL */
+ if (!p || !q)
+ return false;
+
/* same device, id and data */
if (p->dev == q->dev && p->id == q->id && p->data == q->data)
return true;