The HDMI driver request clocks early, but never disable them, leaving
the clocks on even when the driver is removed.
Fix it by slightly refactoring the clock code, and register a devm
action that will eventually disable/unprepare the enabled clocks.
Signed-off-by: Marc Zyngier <[email protected]>
---
drivers/gpu/drm/meson/meson_dw_hdmi.c | 43 ++++++++++++++++++---------
1 file changed, 29 insertions(+), 14 deletions(-)
diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
index 7f8eea494147..29623b309cb1 100644
--- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
+++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
@@ -145,8 +145,6 @@ struct meson_dw_hdmi {
struct reset_control *hdmitx_apb;
struct reset_control *hdmitx_ctrl;
struct reset_control *hdmitx_phy;
- struct clk *hdmi_pclk;
- struct clk *venci_clk;
struct regulator *hdmi_supply;
u32 irq_stat;
struct dw_hdmi *hdmi;
@@ -946,6 +944,29 @@ static void meson_disable_regulator(void *data)
regulator_disable(data);
}
+static void meson_disable_clk(void *data)
+{
+ clk_disable_unprepare(data);
+}
+
+static int meson_enable_clk(struct device *dev, char *name)
+{
+ struct clk *clk;
+ int ret;
+
+ clk = devm_clk_get(dev, name);
+ if (IS_ERR(clk)) {
+ dev_err(dev, "Unable to get %s pclk\n", name);
+ return PTR_ERR(clk);
+ }
+
+ ret = clk_prepare_enable(clk);
+ if (!ret)
+ ret = devm_add_action_or_reset(dev, meson_disable_clk, clk);
+
+ return ret;
+}
+
static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
void *data)
{
@@ -1026,19 +1047,13 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
if (IS_ERR(meson_dw_hdmi->hdmitx))
return PTR_ERR(meson_dw_hdmi->hdmitx);
- meson_dw_hdmi->hdmi_pclk = devm_clk_get(dev, "isfr");
- if (IS_ERR(meson_dw_hdmi->hdmi_pclk)) {
- dev_err(dev, "Unable to get HDMI pclk\n");
- return PTR_ERR(meson_dw_hdmi->hdmi_pclk);
- }
- clk_prepare_enable(meson_dw_hdmi->hdmi_pclk);
+ ret = meson_enable_clk(dev, "isfr");
+ if (ret)
+ return ret;
- meson_dw_hdmi->venci_clk = devm_clk_get(dev, "venci");
- if (IS_ERR(meson_dw_hdmi->venci_clk)) {
- dev_err(dev, "Unable to get venci clk\n");
- return PTR_ERR(meson_dw_hdmi->venci_clk);
- }
- clk_prepare_enable(meson_dw_hdmi->venci_clk);
+ ret = meson_enable_clk(dev, "venci");
+ if (ret)
+ return ret;
dw_plat_data->regm = devm_regmap_init(dev, NULL, meson_dw_hdmi,
&meson_dw_hdmi_regmap_config);
--
2.28.0
On 20/11/2020 10:42, Marc Zyngier wrote:
> The HDMI driver request clocks early, but never disable them, leaving
> the clocks on even when the driver is removed.
>
> Fix it by slightly refactoring the clock code, and register a devm
> action that will eventually disable/unprepare the enabled clocks.
>
> Signed-off-by: Marc Zyngier <[email protected]>
> ---
> drivers/gpu/drm/meson/meson_dw_hdmi.c | 43 ++++++++++++++++++---------
> 1 file changed, 29 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
> index 7f8eea494147..29623b309cb1 100644
> --- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
> +++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
> @@ -145,8 +145,6 @@ struct meson_dw_hdmi {
> struct reset_control *hdmitx_apb;
> struct reset_control *hdmitx_ctrl;
> struct reset_control *hdmitx_phy;
> - struct clk *hdmi_pclk;
> - struct clk *venci_clk;
> struct regulator *hdmi_supply;
> u32 irq_stat;
> struct dw_hdmi *hdmi;
> @@ -946,6 +944,29 @@ static void meson_disable_regulator(void *data)
> regulator_disable(data);
> }
>
> +static void meson_disable_clk(void *data)
> +{
> + clk_disable_unprepare(data);
> +}
> +
> +static int meson_enable_clk(struct device *dev, char *name)
> +{
> + struct clk *clk;
> + int ret;
> +
> + clk = devm_clk_get(dev, name);
> + if (IS_ERR(clk)) {
> + dev_err(dev, "Unable to get %s pclk\n", name);
> + return PTR_ERR(clk);
> + }
> +
> + ret = clk_prepare_enable(clk);
> + if (!ret)
> + ret = devm_add_action_or_reset(dev, meson_disable_clk, clk);
> +
> + return ret;
> +}
> +
> static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
> void *data)
> {
> @@ -1026,19 +1047,13 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
> if (IS_ERR(meson_dw_hdmi->hdmitx))
> return PTR_ERR(meson_dw_hdmi->hdmitx);
>
> - meson_dw_hdmi->hdmi_pclk = devm_clk_get(dev, "isfr");
> - if (IS_ERR(meson_dw_hdmi->hdmi_pclk)) {
> - dev_err(dev, "Unable to get HDMI pclk\n");
> - return PTR_ERR(meson_dw_hdmi->hdmi_pclk);
> - }
> - clk_prepare_enable(meson_dw_hdmi->hdmi_pclk);
> + ret = meson_enable_clk(dev, "isfr");
> + if (ret)
> + return ret;
>
> - meson_dw_hdmi->venci_clk = devm_clk_get(dev, "venci");
> - if (IS_ERR(meson_dw_hdmi->venci_clk)) {
> - dev_err(dev, "Unable to get venci clk\n");
> - return PTR_ERR(meson_dw_hdmi->venci_clk);
> - }
> - clk_prepare_enable(meson_dw_hdmi->venci_clk);
> + ret = meson_enable_clk(dev, "venci");
> + if (ret)
> + return ret;
>
> dw_plat_data->regm = devm_regmap_init(dev, NULL, meson_dw_hdmi,
> &meson_dw_hdmi_regmap_config);
>
Reviewed-by: Neil Armstrong <[email protected]>
On Fri 20 Nov 2020 at 10:42, Marc Zyngier <[email protected]> wrote:
> The HDMI driver request clocks early, but never disable them, leaving
> the clocks on even when the driver is removed.
>
> Fix it by slightly refactoring the clock code, and register a devm
> action that will eventually disable/unprepare the enabled clocks.
>
> Signed-off-by: Marc Zyngier <[email protected]>
> ---
> drivers/gpu/drm/meson/meson_dw_hdmi.c | 43 ++++++++++++++++++---------
> 1 file changed, 29 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c b/drivers/gpu/drm/meson/meson_dw_hdmi.c
> index 7f8eea494147..29623b309cb1 100644
> --- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
> +++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
> @@ -145,8 +145,6 @@ struct meson_dw_hdmi {
> struct reset_control *hdmitx_apb;
> struct reset_control *hdmitx_ctrl;
> struct reset_control *hdmitx_phy;
> - struct clk *hdmi_pclk;
> - struct clk *venci_clk;
> struct regulator *hdmi_supply;
> u32 irq_stat;
> struct dw_hdmi *hdmi;
> @@ -946,6 +944,29 @@ static void meson_disable_regulator(void *data)
> regulator_disable(data);
> }
>
> +static void meson_disable_clk(void *data)
> +{
> + clk_disable_unprepare(data);
> +}
> +
> +static int meson_enable_clk(struct device *dev, char *name)
> +{
> + struct clk *clk;
> + int ret;
> +
> + clk = devm_clk_get(dev, name);
> + if (IS_ERR(clk)) {
> + dev_err(dev, "Unable to get %s pclk\n", name);
> + return PTR_ERR(clk);
> + }
> +
> + ret = clk_prepare_enable(clk);
> + if (!ret)
> + ret = devm_add_action_or_reset(dev, meson_disable_clk,
> clk);
Thanks for fixing this Marc.
FYI, while it is fine to declare a function to disable the clocks, a quick
cast may avoid it
devm_add_action_or_reset(dev, (void(*)(void *))clk_disable_unprepare, clk);
> +
> + return ret;
> +}
> +
> static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
> void *data)
> {
> @@ -1026,19 +1047,13 @@ static int meson_dw_hdmi_bind(struct device *dev, struct device *master,
> if (IS_ERR(meson_dw_hdmi->hdmitx))
> return PTR_ERR(meson_dw_hdmi->hdmitx);
>
> - meson_dw_hdmi->hdmi_pclk = devm_clk_get(dev, "isfr");
> - if (IS_ERR(meson_dw_hdmi->hdmi_pclk)) {
> - dev_err(dev, "Unable to get HDMI pclk\n");
> - return PTR_ERR(meson_dw_hdmi->hdmi_pclk);
> - }
> - clk_prepare_enable(meson_dw_hdmi->hdmi_pclk);
> + ret = meson_enable_clk(dev, "isfr");
> + if (ret)
> + return ret;
>
> - meson_dw_hdmi->venci_clk = devm_clk_get(dev, "venci");
> - if (IS_ERR(meson_dw_hdmi->venci_clk)) {
> - dev_err(dev, "Unable to get venci clk\n");
> - return PTR_ERR(meson_dw_hdmi->venci_clk);
> - }
> - clk_prepare_enable(meson_dw_hdmi->venci_clk);
> + ret = meson_enable_clk(dev, "venci");
> + if (ret)
> + return ret;
>
> dw_plat_data->regm = devm_regmap_init(dev, NULL, meson_dw_hdmi,
> &meson_dw_hdmi_regmap_config);
On 2020-11-23 14:03, Jerome Brunet wrote:
> On Fri 20 Nov 2020 at 10:42, Marc Zyngier <[email protected]> wrote:
>
>> The HDMI driver request clocks early, but never disable them, leaving
>> the clocks on even when the driver is removed.
>>
>> Fix it by slightly refactoring the clock code, and register a devm
>> action that will eventually disable/unprepare the enabled clocks.
>>
>> Signed-off-by: Marc Zyngier <[email protected]>
>> ---
>> drivers/gpu/drm/meson/meson_dw_hdmi.c | 43
>> ++++++++++++++++++---------
>> 1 file changed, 29 insertions(+), 14 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> b/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> index 7f8eea494147..29623b309cb1 100644
>> --- a/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> +++ b/drivers/gpu/drm/meson/meson_dw_hdmi.c
>> @@ -145,8 +145,6 @@ struct meson_dw_hdmi {
>> struct reset_control *hdmitx_apb;
>> struct reset_control *hdmitx_ctrl;
>> struct reset_control *hdmitx_phy;
>> - struct clk *hdmi_pclk;
>> - struct clk *venci_clk;
>> struct regulator *hdmi_supply;
>> u32 irq_stat;
>> struct dw_hdmi *hdmi;
>> @@ -946,6 +944,29 @@ static void meson_disable_regulator(void *data)
>> regulator_disable(data);
>> }
>>
>> +static void meson_disable_clk(void *data)
>> +{
>> + clk_disable_unprepare(data);
>> +}
>> +
>> +static int meson_enable_clk(struct device *dev, char *name)
>> +{
>> + struct clk *clk;
>> + int ret;
>> +
>> + clk = devm_clk_get(dev, name);
>> + if (IS_ERR(clk)) {
>> + dev_err(dev, "Unable to get %s pclk\n", name);
>> + return PTR_ERR(clk);
>> + }
>> +
>> + ret = clk_prepare_enable(clk);
>> + if (!ret)
>> + ret = devm_add_action_or_reset(dev, meson_disable_clk,
>> clk);
>
> Thanks for fixing this Marc.
>
> FYI, while it is fine to declare a function to disable the clocks, a
> quick
> cast may avoid it
>
> devm_add_action_or_reset(dev, (void(*)(void *))clk_disable_unprepare,
> clk);
While this works for now, a change to the clk_disable_unprepare()
prototype (such as adding a second argument) would now go completely
unnoticed (after all, you've cast the function, it *must* be correct,
right?), and someone would spend a few hours trying to track down memory
corruption or some other interesting results.
Yes, casting C functions can be hilarious.
I can see a few uses of this hack in the tree, and I have my pop-corn
ready.
Thanks,
M.
--
Jazz is not dead. It just smells funny...