Add bridged amplifiers to cs42l43

Merge series from Charles Keepax <ckeepax@opensource.cirrus.com>:

In some cs42l43 systems a couple of cs35l56 amplifiers are attached
to the cs42l43's SPI and I2S. On Windows the cs42l43 is controlled
by a SDCA class driver and these two amplifiers are controlled by
firmware running on the cs42l43. However, under Linux the decision
was made to interact with the cs42l43 directly, affording the user
greater control over the audio system. However, this has resulted
in an issue where these two bridged cs35l56 amplifiers are not
populated in ACPI and must be added manually. There is at least an
SDCA extension unit DT entry we can key off.

The process of adding this is handled using a software node, firstly the
ability to add native chip selects to software nodes must be added.
Secondly, an additional flag for naming the SPI devices is added this
allows the machine driver to key to the correct amplifier. Then finally,
the cs42l43 SPI driver adds the two amplifiers directly onto its SPI
bus.

An additional series will follow soon to add the audio machine driver
parts (in the sof-sdw driver), however that is fairly orthogonal to
this part of the process, getting the actual amplifiers registered.

1 files changed, 36 insertions, 2 deletions

diff --git a/drivers/s390/net/qeth_core_main.c b/drivers/s390/net/qeth_core_main.c
index a0cce6872075d..f0b8b709649f2 100644
--- a/drivers/s390/net/qeth_core_main.c
+++ b/drivers/s390/net/qeth_core_main.c
@@ -1179,6 +1179,20 @@ static int qeth_check_irb_error(struct qeth_card *card, struct ccw_device *cdev,
 	}
 }
 
+/**
+ * qeth_irq() - qeth interrupt handler
+ * @cdev: ccw device
+ * @intparm: expect pointer to iob
+ * @irb: Interruption Response Block
+ *
+ * In the good path:
+ * corresponding qeth channel is locked with last used iob as active_cmd.
+ * But this function is also called for error interrupts.
+ *
+ * Caller ensures that:
+ * Interrupts are disabled; ccw device lock is held;
+ *
+ */
 static void qeth_irq(struct ccw_device *cdev, unsigned long intparm,
 		struct irb *irb)
 {
@@ -1220,11 +1234,10 @@ static void qeth_irq(struct ccw_device *cdev, unsigned long intparm,
 		iob = (struct qeth_cmd_buffer *) (addr_t)intparm;
 	}
 
-	qeth_unlock_channel(card, channel);
-
 	rc = qeth_check_irb_error(card, cdev, irb);
 	if (rc) {
 		/* IO was terminated, free its resources. */
+		qeth_unlock_channel(card, channel);
 		if (iob)
 			qeth_cancel_cmd(iob, rc);
 		return;
@@ -1268,6 +1281,7 @@ static void qeth_irq(struct ccw_device *cdev, unsigned long intparm,
 		rc = qeth_get_problem(card, cdev, irb);
 		if (rc) {
 			card->read_or_write_problem = 1;
+			qeth_unlock_channel(card, channel);
 			if (iob)
 				qeth_cancel_cmd(iob, rc);
 			qeth_clear_ipacmd_list(card);
@@ -1276,6 +1290,26 @@ static void qeth_irq(struct ccw_device *cdev, unsigned long intparm,
 		}
 	}
 
+	if (scsw_cmd_is_valid_cc(&irb->scsw) && irb->scsw.cmd.cc == 1 && iob) {
+		/* channel command hasn't started: retry.
+		 * active_cmd is still set to last iob
+		 */
+		QETH_CARD_TEXT(card, 2, "irqcc1");
+		rc = ccw_device_start_timeout(cdev, __ccw_from_cmd(iob),
+					      (addr_t)iob, 0, 0, iob->timeout);
+		if (rc) {
+			QETH_DBF_MESSAGE(2,
+					 "ccw retry on %x failed, rc = %i\n",
+					 CARD_DEVID(card), rc);
+			QETH_CARD_TEXT_(card, 2, " err%d", rc);
+			qeth_unlock_channel(card, channel);
+			qeth_cancel_cmd(iob, rc);
+		}
+		return;
+	}
+
+	qeth_unlock_channel(card, channel);
+
 	if (iob) {
 		/* sanity check: */
 		if (irb->scsw.cmd.count > iob->length) {