[PATCH 4.19 159/346] Input: omap4-keypad - fix runtime PM error handling

Greg Kroah-Hartman
2020-12-28T13:29:47Z

From: Zhang Qilong <zhangqilong3@huawei.com>

[ Upstream commit 59bbf83835f591b95c3bdd09d900f3584fa227af ]

In omap4_keypad_probe, the patch fix several bugs.

1) pm_runtime_get_sync will increment pm usage counter even it
failed. Forgetting to pm_runtime_put_noidle will result in
reference leak.

2) In err_unmap, forget to disable runtime of device,
pm_runtime_enable will increase power disable depth. Thus a
pairing decrement is needed on the error handling path to keep
it balanced.

3) In err_pm_disable, it will call pm_runtime_put_sync twice not
one time.

To fix this we factor out code reading revision and disabling touchpad, and
drop PM reference once we are done talking to the device.

Fixes: f77621cc640a7 ("Input: omap-keypad - dynamically handle register offsets")
Fixes: 5ad567ffbaf20 ("Input: omap4-keypad - wire up runtime PM handling")
Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Link: https://lore.kernel.org/r/20201120133918.2559681-1-zhangqilong3@huawei.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/input/keyboard/omap4-keypad.c | 89 ++++++++++++++++-----------
1 file changed, 53 insertions(+), 36 deletions(-)

diff --git a/drivers/input/keyboard/omap4-keypad.c b/drivers/input/keyboard/omap4-keypad.c
index aeeef50cef9bb..adb1ecc969eeb 100644
--- a/drivers/input/keyboard/omap4-keypad.c
+++ b/drivers/input/keyboard/omap4-keypad.c
@@ -199,12 +199,8 @@ static int omap4_keypad_open(struct input_dev *input)
return 0;
}

-static void omap4_keypad_close(struct input_dev *input)
+static void omap4_keypad_stop(struct omap4_keypad *keypad_data)
{
- struct omap4_keypad *keypad_data = input_get_drvdata(input);
-
- disable_irq(keypad_data->irq);
-
/* Disable interrupts and wake-up events */
kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQENABLE,
OMAP4_VAL_IRQDISABLE);
@@ -213,7 +209,15 @@ static void omap4_keypad_close(struct input_dev *input)
/* clear pending interrupts */
kbd_write_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS,
kbd_read_irqreg(keypad_data, OMAP4_KBD_IRQSTATUS));
+}
+
+static void omap4_keypad_close(struct input_dev *input)
+{
+ struct omap4_keypad *keypad_data;

+ keypad_data = input_get_drvdata(input);
+ disable_irq(keypad_data->irq);
+ omap4_keypad_stop(keypad_data);
enable_irq(keypad_data->irq);

pm_runtime_put_sync(input->dev.parent);
@@ -236,13 +240,37 @@ static int omap4_keypad_parse_dt(struct device *dev,
return 0;
}

+static int omap4_keypad_check_revision(struct device *dev,
+ struct omap4_keypad *keypad_data)
+{
+ unsigned int rev;
+
+ rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
+ rev &= 0x03 << 30;
+ rev >>= 30;
+ switch (rev) {
+ case KBD_REVISION_OMAP4:
+ keypad_data->reg_offset = 0x00;
+ keypad_data->irqreg_offset = 0x00;
+ break;
+ case KBD_REVISION_OMAP5:
+ keypad_data->reg_offset = 0x10;
+ keypad_data->irqreg_offset = 0x0c;
+ break;
+ default:
+ dev_err(dev, "Keypad reports unsupported revision %d", rev);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
static int omap4_keypad_probe(struct platform_device *pdev)
{
struct omap4_keypad *keypad_data;
struct input_dev *input_dev;
struct resource *res;
unsigned int max_keys;
- int rev;
int irq;
int error;

@@ -282,41 +310,33 @@ static int omap4_keypad_probe(struct platform_device *pdev)
goto err_release_mem;
}

+ pm_runtime_enable(&pdev->dev);

/*
* Enable clocks for the keypad module so that we can read
* revision register.
*/
- pm_runtime_enable(&pdev->dev);
error = pm_runtime_get_sync(&pdev->dev);
if (error) {
dev_err(&pdev->dev, "pm_runtime_get_sync() failed\n");
- goto err_unmap;
- }
- rev = __raw_readl(keypad_data->base + OMAP4_KBD_REVISION);
- rev &= 0x03 << 30;
- rev >>= 30;
- switch (rev) {
- case KBD_REVISION_OMAP4:
- keypad_data->reg_offset = 0x00;
- keypad_data->irqreg_offset = 0x00;
- break;
- case KBD_REVISION_OMAP5:
- keypad_data->reg_offset = 0x10;
- keypad_data->irqreg_offset = 0x0c;
- break;
- default:
- dev_err(&pdev->dev,
- "Keypad reports unsupported revision %d", rev);
- error = -EINVAL;
- goto err_pm_put_sync;
+ pm_runtime_put_noidle(&pdev->dev);
+ } else {
+ error = omap4_keypad_check_revision(&pdev->dev,
+ keypad_data);
+ if (!error) {
+ /* Ensure device does not raise interrupts */
+ omap4_keypad_stop(keypad_data);
+ }
+ pm_runtime_put_sync(&pdev->dev);
}
+ if (error)
+ goto err_pm_disable;

/* input device allocation */
keypad_data->input = input_dev = input_allocate_device();
if (!input_dev) {
error = -ENOMEM;
- goto err_pm_put_sync;
+ goto err_pm_disable;
}

input_dev->name = pdev->name;
@@ -362,28 +382,25 @@ static int omap4_keypad_probe(struct platform_device *pdev)
goto err_free_keymap;
}

- device_init_wakeup(&pdev->dev, true);
- pm_runtime_put_sync(&pdev->dev);
-
error = input_register_device(keypad_data->input);
if (error < 0) {
dev_err(&pdev->dev, "failed to register input device\n");
- goto err_pm_disable;
+ goto err_free_irq;
}

+ device_init_wakeup(&pdev->dev, true);
platform_set_drvdata(pdev, keypad_data);
+
return 0;

-err_pm_disable:
- pm_runtime_disable(&pdev->dev);
+err_free_irq:
free_irq(keypad_data->irq, keypad_data);
err_free_keymap:
kfree(keypad_data->keymap);
err_free_input:
input_free_device(input_dev);
-err_pm_put_sync:
- pm_runtime_put_sync(&pdev->dev);
-err_unmap:
+err_pm_disable:
+ pm_runtime_disable(&pdev->dev);
iounmap(keypad_data->base);
err_release_mem:
release_mem_region(res->start, resource_size(res));
--
2.27.0