counter: 104-quad-8: Add lock guards - differential encoder (708d9893) · Commits · 戴 / test

drivers/counter/104-quad-8.c

+15 −3

Original line number	Original line	Diff line number	Diff line
	@@ -1274,18 +1274,26 @@ static ssize_t quad8_signal_cable_fault_read(struct counter_device *counter,
	struct counter_signal *signal,		struct counter_signal *signal,
	void private, char buf)		void private, char buf)
	{		{
	const struct quad8_iio *const priv = counter->priv;		struct quad8_iio *const priv = counter->priv;
	const size_t channel_id = signal->id / 2;		const size_t channel_id = signal->id / 2;
	const bool disabled = !(priv->cable_fault_enable & BIT(channel_id));		bool disabled;
	unsigned int status;		unsigned int status;
	unsigned int fault;		unsigned int fault;

	if (disabled)		mutex_lock(&priv->lock);

			disabled = !(priv->cable_fault_enable & BIT(channel_id));

			if (disabled) {
			mutex_unlock(&priv->lock);
	return -EINVAL;		return -EINVAL;
			}

	/* Logic 0 = cable fault */		/* Logic 0 = cable fault */
	status = inb(priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);		status = inb(priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);

			mutex_unlock(&priv->lock);

	/* Mask respective channel and invert logic */		/* Mask respective channel and invert logic */
	fault = !(status & BIT(channel_id));		fault = !(status & BIT(channel_id));

	@@ -1317,6 +1325,8 @@ static ssize_t quad8_signal_cable_fault_enable_write(
	if (ret)		if (ret)
	return ret;		return ret;

			mutex_lock(&priv->lock);

	if (enable)		if (enable)
	priv->cable_fault_enable \|= BIT(channel_id);		priv->cable_fault_enable \|= BIT(channel_id);
	else		else
	@@ -1327,6 +1337,8 @@ static ssize_t quad8_signal_cable_fault_enable_write(

	outb(cable_fault_enable, priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);		outb(cable_fault_enable, priv->base + QUAD8_DIFF_ENCODER_CABLE_STATUS);

			mutex_unlock(&priv->lock);

	return len;		return len;
	}		}

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