On Sun, Nov 20, 2022 at 03:15:09PM +0100, Marek Vasut wrote:
> Currently this driver triggers extcon and typec state update in its
> probe function, to read out current state reported by the chip and
> report the correct state to upper layers. This synchronization is
> performed correctly, but only in case the chip indicates a pending
> interrupt in reg09 register.
>
> This fails to cover the situation where all interrupts reported by
> the chip were already handled by Linux before reboot, then the system
> rebooted, and then Linux starts again. In this case, the TUSB320 no
> longer reports any interrupts in reg09, and the state update does not
> perform any update as it depends on that interrupt indication.
>
> Fix this by turning tusb320_irq_handler() into a thin wrapper around
> tusb320_state_update_handler(), where the later now contains the bulk
> of the code of tusb320_irq_handler(), but adds new function parameter
> "force_update". The "force_update" parameter can be used by the probe
> function to assure that the state synchronization is always performed,
> independent of the interrupt indicated in reg09. The interrupt handler
> tusb320_irq_handler() callback uses force_update=false to avoid state
> updates on potential spurious interrupts and retain current behavior.
>
> Fixes: 06bc4ca115cdd ("extcon: Add driver for TI TUSB320")
> Signed-off-by: Marek Vasut <marex@xxxxxxx>
Acked-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> ---
> Cc: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>
> Cc: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> Cc: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>
> Cc: MyungJoo Ham <myungjoo.ham@xxxxxxxxxxx>
> Cc: Yassine Oudjana <y.oudjana@xxxxxxxxxxxxxx>
> ---
> drivers/extcon/extcon-usbc-tusb320.c | 17 ++++++++++++-----
> 1 file changed, 12 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/extcon/extcon-usbc-tusb320.c b/drivers/extcon/extcon-usbc-tusb320.c
> index 2a120d8d3c272..9dfa545427ca1 100644
> --- a/drivers/extcon/extcon-usbc-tusb320.c
> +++ b/drivers/extcon/extcon-usbc-tusb320.c
> @@ -313,9 +313,9 @@ static void tusb320_typec_irq_handler(struct tusb320_priv *priv, u8 reg9)
> typec_set_pwr_opmode(port, TYPEC_PWR_MODE_USB);
> }
>
> -static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
> +static irqreturn_t tusb320_state_update_handler(struct tusb320_priv *priv,
> + bool force_update)
> {
> - struct tusb320_priv *priv = dev_id;
> unsigned int reg;
>
> if (regmap_read(priv->regmap, TUSB320_REG9, ®)) {
> @@ -323,7 +323,7 @@ static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
> return IRQ_NONE;
> }
>
> - if (!(reg & TUSB320_REG9_INTERRUPT_STATUS))
> + if (!force_update && !(reg & TUSB320_REG9_INTERRUPT_STATUS))
> return IRQ_NONE;
>
> tusb320_extcon_irq_handler(priv, reg);
> @@ -340,6 +340,13 @@ static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
> return IRQ_HANDLED;
> }
>
> +static irqreturn_t tusb320_irq_handler(int irq, void *dev_id)
> +{
> + struct tusb320_priv *priv = dev_id;
> +
> + return tusb320_state_update_handler(priv, false);
> +}
> +
> static const struct regmap_config tusb320_regmap_config = {
> .reg_bits = 8,
> .val_bits = 8,
> @@ -466,7 +473,7 @@ static int tusb320_probe(struct i2c_client *client,
> return ret;
>
> /* update initial state */
> - tusb320_irq_handler(client->irq, priv);
> + tusb320_state_update_handler(priv, true);
>
> /* Reset chip to its default state */
> ret = tusb320_reset(priv);
> @@ -477,7 +484,7 @@ static int tusb320_probe(struct i2c_client *client,
> * State and polarity might change after a reset, so update
> * them again and make sure the interrupt status bit is cleared.
> */
> - tusb320_irq_handler(client->irq, priv);
> + tusb320_state_update_handler(priv, true);
>
> ret = devm_request_threaded_irq(priv->dev, client->irq, NULL,
> tusb320_irq_handler,
thanks,
--
heikki
