[PATCH v6 4/4] ASoC: wm8994: drain delayed works on remove and probe error

[Tristan Madani <tristmd@gmail.com>]

From: Tristan Madani <tristan@talencesecurity.com>

wm8994_component_probe() schedules several delayed works to handle jack
detection and microphone status polling.  If the component is removed or
probe fails after these works are scheduled, they can execute after
resources are freed.

Cancel all pending delayed works in the error and removal paths.  Guard
cancel_delayed_work_sync(&wm8994->mic_work) with a type check because
INIT_DELAYED_WORK for mic_work only runs in the WM8994 and WM1811 code
paths.

Cancel mic_work before and after jackdet_bootstrap because the two can
re-arm each other: wm1811_mic_work() can re-arm jackdet_bootstrap
through the DAPM power-up chain (force-enabling MICBIAS2 triggers
clk_sys_event which queues jackdet_bootstrap), and
wm1811_jackdet_bootstrap() detects a jack and ultimately queues
mic_work.  The second mic_work cancel catches any re-arm from a
jackdet_bootstrap handler that was in flight during the first cancel.

Fixes: 99af79dff5a6 ("ASoC: wm8994: Ensure we get a notification on startup for jackdet")
Cc: stable@vger.kernel.org
Signed-off-by: Tristan Madani <tristan@talencesecurity.com>
---
Changes in v6:
- Add comments clarifying why mic_work is cancelled twice, per
  Charles Keepax review.  No functional change.

 sound/soc/codecs/wm8994.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/sound/soc/codecs/wm8994.c b/sound/soc/codecs/wm8994.c
index 6b91e02f130b3..6a790479c8a7e 100644
--- a/sound/soc/codecs/wm8994.c
+++ b/sound/soc/codecs/wm8994.c
@@ -4595,6 +4595,14 @@ static int wm8994_component_probe(struct snd_soc_component *component)
 	wm8994_free_irq(wm8994->wm8994, WM8994_IRQ_FIFOS_ERR, component);
 	wm8994_free_irq(wm8994->wm8994, WM8994_IRQ_TEMP_SHUT, component);
 	wm8994_free_irq(wm8994->wm8994, WM8994_IRQ_TEMP_WARN, component);
+	if (control->type == WM8994 || control->type == WM1811)
+		cancel_delayed_work_sync(&wm8994->mic_work);
+	cancel_delayed_work_sync(&wm8994->jackdet_bootstrap);
+	/* Catch mic_work re-armed by jackdet_bootstrap running concurrently. */
+	if (control->type == WM8994 || control->type == WM1811)
+		cancel_delayed_work_sync(&wm8994->mic_work);
+	cancel_delayed_work_sync(&wm8994->mic_complete_work);
+	cancel_delayed_work_sync(&wm8994->open_circuit_work);
 
 	return ret;
 }
@@ -4636,6 +4644,14 @@ static void wm8994_component_remove(struct snd_soc_component *component)
 			free_irq(wm8994->micdet_irq, wm8994);
 		break;
 	}
+	if (control->type == WM8994 || control->type == WM1811)
+		cancel_delayed_work_sync(&wm8994->mic_work);
+	cancel_delayed_work_sync(&wm8994->jackdet_bootstrap);
+	/* Catch mic_work re-armed by jackdet_bootstrap running concurrently. */
+	if (control->type == WM8994 || control->type == WM1811)
+		cancel_delayed_work_sync(&wm8994->mic_work);
+	cancel_delayed_work_sync(&wm8994->mic_complete_work);
+	cancel_delayed_work_sync(&wm8994->open_circuit_work);
 	release_firmware(wm8994->mbc);
 	release_firmware(wm8994->mbc_vss);
 	release_firmware(wm8994->enh_eq);
-- 
2.47.3