[PATCH] drm/bridge: it6505: Disable IRQ when powered off

From: Pin-yen Lin
Date: Fri Jul 19 2024 - 07:06:45 EST


When the bridge is powered off, disable the IRQ until the next power on
to workaround an interrupt storm on some badly-designed hardware.

Signed-off-by: Pin-yen Lin <treapking@xxxxxxxxxxxx>
---

drivers/gpu/drm/bridge/ite-it6505.c | 17 ++++++++++++-----
1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 1e1c06fdf206..87b8545fccc0 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -460,6 +460,8 @@ struct it6505 {
bool enable_drv_hold;

const struct drm_edid *cached_edid;
+
+ int irq;
};

struct it6505_step_train_para {
@@ -2624,6 +2626,8 @@ static int it6505_poweron(struct it6505 *it6505)
it6505_init(it6505);
it6505_lane_off(it6505);

+ enable_irq(it6505->irq);
+
return 0;
}

@@ -2640,6 +2644,8 @@ static int it6505_poweroff(struct it6505 *it6505)
return 0;
}

+ disable_irq_nosync(it6505->irq);
+
if (pdata->gpiod_reset)
gpiod_set_value_cansleep(pdata->gpiod_reset, 0);

@@ -3389,7 +3395,7 @@ static int it6505_i2c_probe(struct i2c_client *client)
struct it6505 *it6505;
struct device *dev = &client->dev;
struct extcon_dev *extcon;
- int err, intp_irq;
+ int err;

it6505 = devm_kzalloc(&client->dev, sizeof(*it6505), GFP_KERNEL);
if (!it6505)
@@ -3430,17 +3436,18 @@ static int it6505_i2c_probe(struct i2c_client *client)

it6505_parse_dt(it6505);

- intp_irq = client->irq;
+ it6505->irq = client->irq;

- if (!intp_irq) {
+ if (!it6505->irq) {
dev_err(dev, "Failed to get INTP IRQ");
err = -ENODEV;
return err;
}

- err = devm_request_threaded_irq(&client->dev, intp_irq, NULL,
+ err = devm_request_threaded_irq(&client->dev, it6505->irq, NULL,
it6505_int_threaded_handler,
- IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT |
+ IRQF_NO_AUTOEN,
"it6505-intp", it6505);
if (err) {
dev_err(dev, "Failed to request INTP threaded IRQ: %d", err);
--
2.45.2.1089.g2a221341d9-goog