Kalle Valo [off-list ref] writes:

From: Erik Stromdahl <redacted>

sdio/mailbox HIF implementation.

Signed-off-by: Erik Stromdahl <redacted>
Signed-off-by: Kalle Valo <redacted>

[...]

+static int ath10k_sdio_mbox_proc_cpu_intr(struct ath10k *ar)
+{
+	struct ath10k_sdio *ar_sdio =3D ath10k_sdio_priv(ar);
+	struct ath10k_sdio_irq_data *irq_data =3D &ar_sdio->irq_data;
+	u8 cpu_int_status, *reg_buf;
+	int ret;
+
+	mutex_lock(&irq_data->mtx);
+	cpu_int_status =3D irq_data->irq_proc_reg->cpu_int_status &
+			 irq_data->irq_en_reg->cpu_int_status_en;
+	if (!cpu_int_status) {
+		ath10k_warn(ar, "CPU interrupt status is zero\n");
+		return -EIO;
+	}
+
+	/* Clear the interrupt */
+	irq_data->irq_proc_reg->cpu_int_status &=3D ~cpu_int_status;
+
+	/* Set up the register transfer buffer to hit the register 4 times ,
+	 * this is done to make the access 4-byte aligned to mitigate issues
+	 * with host bus interconnects that restrict bus transfer lengths to
+	 * be a multiple of 4-bytes.
+	 */
+	reg_buf =3D kzalloc(4, GFP_KERNEL);
+	if (!reg_buf)
+		return -ENOMEM;

kbuild bot reported that I failed to release the mutex in these two
return cases above, I'll fix that in v7.

--=20
Kalle Valo=