[PATCH v5 00/17] net: qualcomm: add QCA7000 UART driver

[PATCH v5 00/17] net: qualcomm: add QCA7000 UART driver

[Stefan Wahren]

The Qualcomm QCA7000 HomePlug GreenPHY supports two interfaces:
UART and SPI. This patch series adds the missing support for UART.

This driver based on the Qualcomm code [1], but contains some changes:
* use random MAC address per default
* use net_device_stats from device
* share frame decoding between SPI and UART driver
* improve error handling
* reimplement tty_wakeup with work queue (based on slcan)
* use new serial device bus instead of ldisc

The patches 1 - 3 are just for clean up and are not related to
the UART support. Patches 4 - 15 prepare the existing QCA7000
code for UART support. Patch 16 is a improvement for serial device
bus. Patch 17 contains the new driver.

Cherry picking of the dt-bindings and serdev patch is okay. The
UART driver functionally (not compile) depends on this unmerged
patch [2].

The code itself has been tested on a Freescale i.MX28 board and
a Raspberry Pi Zero.

Changes in v5:
  * rebase to current linux-next
  * fix alignment issues in rx path
  * fix buffer overrun with big ethernet frames
  * fix init of UART decoding fsm
  * add device UART settings to Kconfig help
  * add current-speed to slave-device binding
  * merge SPI and UART binding document
  * rename qca_common to qca_7k_common
  * drop patch for retrieving UART settings
  * several cleanups

Changes in v4:
  * rebase to current linux-next
  * use parameter -M for git format-patch
  * change order of local variables where possible
  * implement basic serdev support (without hardware flow control)

Changes in v3:
  * rebase to current net-next

Changes in v2:
  * fix build issue by using netif_trans_update() and dev_trans_start()

[1] - https://github.com/IoE/qca7000
[2] - http://marc.info/?l=linux-serial&m=149338017301309&w=2

Stefan Wahren (17):
  net: qualcomm: remove unnecessary includes
  net: qca_framing: use u16 for frame offset
  net: qca_7k: Use BIT macro
  net: qualcomm: use net_device_ops instead of direct call
  net: qualcomm: Improve readability of length defines
  net: qca_spi: remove QCASPI_MTU
  net: qualcomm: move qcaspi_tx_cmd to qca_spi.c
  net: qca_spi: Clarify MODULE_DESCRIPTION
  net: qualcomm: rename qca_framing.c to qca_7k_common.c
  net: qualcomm: prepare frame decoding for UART driver
  net: qualcomm: make qca_7k_common a separate kernel module
  dt-bindings: qca7000-spi: Rework binding
  dt-bindings: qca7000: rename binding
  dt-bindings: slave-device: add current-speed property
  dt-bindings: qca7000: append UART interface to binding
  tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrate
  net: qualcomm: add QCA7000 UART driver

 .../devicetree/bindings/net/qca-qca7000-spi.txt    |  47 ---
 .../devicetree/bindings/net/qca-qca7000.txt        |  88 +++++
 .../devicetree/bindings/serial/slave-device.txt    |   9 +
 drivers/net/ethernet/qualcomm/Kconfig              |  24 +-
 drivers/net/ethernet/qualcomm/Makefile             |   7 +-
 drivers/net/ethernet/qualcomm/qca_7k.c             |  28 --
 drivers/net/ethernet/qualcomm/qca_7k.h             |  15 +-
 .../qualcomm/{qca_framing.c => qca_7k_common.c}    |  26 +-
 .../qualcomm/{qca_framing.h => qca_7k_common.h}    |  24 +-
 drivers/net/ethernet/qualcomm/qca_debug.c          |   5 +-
 drivers/net/ethernet/qualcomm/qca_spi.c            |  47 ++-
 drivers/net/ethernet/qualcomm/qca_spi.h            |   5 +-
 drivers/net/ethernet/qualcomm/qca_uart.c           | 423 +++++++++++++++++++++
 drivers/tty/serdev/serdev-ttyport.c                |   2 +-
 14 files changed, 630 insertions(+), 120 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
 create mode 100644 Documentation/devicetree/bindings/net/qca-qca7000.txt
 rename drivers/net/ethernet/qualcomm/{qca_framing.c => qca_7k_common.c} (85%)
 rename drivers/net/ethernet/qualcomm/{qca_framing.h => qca_7k_common.h} (86%)
 create mode 100644 drivers/net/ethernet/qualcomm/qca_uart.c

-- 
2.1.4

[PATCH v5 01/17] net: qualcomm: remove unnecessary includes

[Stefan Wahren]

Most of the includes in qca_7k.c are unnecessary so we better remove them.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_7k.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_7k.c b/drivers/net/ethernet/qualcomm/qca_7k.c
index f0066fb..557d53c 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k.c
+++ b/drivers/net/ethernet/qualcomm/qca_7k.c
@@ -23,11 +23,7 @@
  *   kernel-based SPI device.
  */
 
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
 #include <linux/spi/spi.h>
-#include <linux/version.h>
 
 #include "qca_7k.h"
 
-- 
2.1.4

[PATCH v5 02/17] net: qca_framing: use u16 for frame offset

[Stefan Wahren]

It doesn't make sense to use a signed variable for offset here, so
fix it up.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_framing.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_framing.h b/drivers/net/ethernet/qualcomm/qca_framing.h
index d5e795d..8b385e6 100644
--- a/drivers/net/ethernet/qualcomm/qca_framing.h
+++ b/drivers/net/ethernet/qualcomm/qca_framing.h
@@ -103,7 +103,7 @@ struct qcafrm_handle {
 	enum qcafrm_state state;
 
 	/* Offset in buffer (borrowed for length too) */
-	s16 offset;
+	u16 offset;
 
 	/* Frame length as kept by this module */
 	u16 len;
-- 
2.1.4

[PATCH v5 03/17] net: qca_7k: Use BIT macro

[Stefan Wahren]

Use the BIT macro for the CONFIG and INT register values.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_7k.h | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_7k.h b/drivers/net/ethernet/qualcomm/qca_7k.h
index 1cad851..4047f0a 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k.h
+++ b/drivers/net/ethernet/qualcomm/qca_7k.h
@@ -54,15 +54,15 @@
 #define SPI_REG_ACTION_CTRL     0x1B00
 
 /*   SPI_CONFIG register definition;             */
-#define QCASPI_SLAVE_RESET_BIT (1 << 6)
+#define QCASPI_SLAVE_RESET_BIT  BIT(6)
 
 /*   INTR_CAUSE/ENABLE register definition.      */
-#define SPI_INT_WRBUF_BELOW_WM (1 << 10)
-#define SPI_INT_CPU_ON         (1 << 6)
-#define SPI_INT_ADDR_ERR       (1 << 3)
-#define SPI_INT_WRBUF_ERR      (1 << 2)
-#define SPI_INT_RDBUF_ERR      (1 << 1)
-#define SPI_INT_PKT_AVLBL      (1 << 0)
+#define SPI_INT_WRBUF_BELOW_WM  BIT(10)
+#define SPI_INT_CPU_ON          BIT(6)
+#define SPI_INT_ADDR_ERR        BIT(3)
+#define SPI_INT_WRBUF_ERR       BIT(2)
+#define SPI_INT_RDBUF_ERR       BIT(1)
+#define SPI_INT_PKT_AVLBL       BIT(0)
 
 void qcaspi_spi_error(struct qcaspi *qca);
 int qcaspi_read_register(struct qcaspi *qca, u16 reg, u16 *result);
-- 
2.1.4

[PATCH v5 04/17] net: qualcomm: use net_device_ops instead of direct call

[Stefan Wahren]

There is no need to export qcaspi_netdev_open and qcaspi_netdev_close
because they are also accessible via the net_device_ops.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_debug.c | 5 +++--
 drivers/net/ethernet/qualcomm/qca_spi.c   | 4 ++--
 drivers/net/ethernet/qualcomm/qca_spi.h   | 3 ---
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_debug.c b/drivers/net/ethernet/qualcomm/qca_debug.c
index d145df9..92b6be9 100644
--- a/drivers/net/ethernet/qualcomm/qca_debug.c
+++ b/drivers/net/ethernet/qualcomm/qca_debug.c
@@ -275,6 +275,7 @@ qcaspi_get_ringparam(struct net_device *dev, struct ethtool_ringparam *ring)
 static int
 qcaspi_set_ringparam(struct net_device *dev, struct ethtool_ringparam *ring)
 {
+	const struct net_device_ops *ops = dev->netdev_ops;
 	struct qcaspi *qca = netdev_priv(dev);
 
 	if ((ring->rx_pending) ||
@@ -283,13 +284,13 @@ qcaspi_set_ringparam(struct net_device *dev, struct ethtool_ringparam *ring)
 		return -EINVAL;
 
 	if (netif_running(dev))
-		qcaspi_netdev_close(dev);
+		ops->ndo_stop(dev);
 
 	qca->txr.count = max_t(u32, ring->tx_pending, TX_RING_MIN_LEN);
 	qca->txr.count = min_t(u16, qca->txr.count, TX_RING_MAX_LEN);
 
 	if (netif_running(dev))
-		qcaspi_netdev_open(dev);
+		ops->ndo_open(dev);
 
 	return 0;
 }
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index 8590109..5c79612 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -602,7 +602,7 @@ qcaspi_intr_handler(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-int
+static int
 qcaspi_netdev_open(struct net_device *dev)
 {
 	struct qcaspi *qca = netdev_priv(dev);
@@ -639,7 +639,7 @@ qcaspi_netdev_open(struct net_device *dev)
 	return 0;
 }
 
-int
+static int
 qcaspi_netdev_close(struct net_device *dev)
 {
 	struct qcaspi *qca = netdev_priv(dev);
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.h b/drivers/net/ethernet/qualcomm/qca_spi.h
index 6e31a0e..064853d 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.h
+++ b/drivers/net/ethernet/qualcomm/qca_spi.h
@@ -108,7 +108,4 @@ struct qcaspi {
 	u16 burst_len;
 };
 
-int qcaspi_netdev_open(struct net_device *dev);
-int qcaspi_netdev_close(struct net_device *dev);
-
 #endif /* _QCA_SPI_H */
-- 
2.1.4

[PATCH v5 05/17] net: qualcomm: Improve readability of length defines

[Stefan Wahren]

In order to avoid mixing things up, make the MTU and frame length
defines easier to read.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_framing.c |  2 +-
 drivers/net/ethernet/qualcomm/qca_framing.h |  8 ++++----
 drivers/net/ethernet/qualcomm/qca_spi.c     | 12 ++++++------
 3 files changed, 11 insertions(+), 11 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_framing.c b/drivers/net/ethernet/qualcomm/qca_framing.c
index faa924c..2341f2b 100644
--- a/drivers/net/ethernet/qualcomm/qca_framing.c
+++ b/drivers/net/ethernet/qualcomm/qca_framing.c
@@ -117,7 +117,7 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 		break;
 	case QCAFRM_WAIT_RSVD_BYTE2:
 		len = handle->offset;
-		if (len > buf_len || len < QCAFRM_ETHMINLEN) {
+		if (len > buf_len || len < QCAFRM_MIN_LEN) {
 			ret = QCAFRM_INVLEN;
 			handle->state = QCAFRM_HW_LEN0;
 		} else {
diff --git a/drivers/net/ethernet/qualcomm/qca_framing.h b/drivers/net/ethernet/qualcomm/qca_framing.h
index 8b385e6..5df7c65 100644
--- a/drivers/net/ethernet/qualcomm/qca_framing.h
+++ b/drivers/net/ethernet/qualcomm/qca_framing.h
@@ -44,12 +44,12 @@
 #define QCAFRM_INVFRAME (QCAFRM_ERR_BASE - 4)
 
 /* Min/Max Ethernet MTU: 46/1500 */
-#define QCAFRM_ETHMINMTU (ETH_ZLEN - ETH_HLEN)
-#define QCAFRM_ETHMAXMTU ETH_DATA_LEN
+#define QCAFRM_MIN_MTU (ETH_ZLEN - ETH_HLEN)
+#define QCAFRM_MAX_MTU ETH_DATA_LEN
 
 /* Min/Max frame lengths */
-#define QCAFRM_ETHMINLEN (QCAFRM_ETHMINMTU + ETH_HLEN)
-#define QCAFRM_ETHMAXLEN (QCAFRM_ETHMAXMTU + VLAN_ETH_HLEN)
+#define QCAFRM_MIN_LEN (QCAFRM_MIN_MTU + ETH_HLEN)
+#define QCAFRM_MAX_LEN (QCAFRM_MAX_MTU + VLAN_ETH_HLEN)
 
 /* QCA7K header len */
 #define QCAFRM_HEADER_LEN 8
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index 5c79612..a0dbb92 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -69,7 +69,7 @@ static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN;
 module_param(qcaspi_pluggable, int, 0);
 MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no).");
 
-#define QCASPI_MTU QCAFRM_ETHMAXMTU
+#define QCASPI_MTU QCAFRM_MAX_MTU
 #define QCASPI_TX_TIMEOUT (1 * HZ)
 #define QCASPI_QCA7K_REBOOT_TIME_MS 1000
 
@@ -402,7 +402,7 @@ qcaspi_tx_ring_has_space(struct tx_ring *txr)
 	if (txr->skb[txr->tail])
 		return 0;
 
-	return (txr->size + QCAFRM_ETHMAXLEN < QCASPI_HW_BUF_LEN) ? 1 : 0;
+	return (txr->size + QCAFRM_MAX_LEN < QCASPI_HW_BUF_LEN) ? 1 : 0;
 }
 
 /*   Flush the tx ring. This function is only safe to
@@ -666,8 +666,8 @@ qcaspi_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
 	struct sk_buff *tskb;
 	u8 pad_len = 0;
 
-	if (skb->len < QCAFRM_ETHMINLEN)
-		pad_len = QCAFRM_ETHMINLEN - skb->len;
+	if (skb->len < QCAFRM_MIN_LEN)
+		pad_len = QCAFRM_MIN_LEN - skb->len;
 
 	if (qca->txr.skb[qca->txr.tail]) {
 		netdev_warn(qca->net_dev, "queue was unexpectedly full!\n");
@@ -804,8 +804,8 @@ qcaspi_netdev_setup(struct net_device *dev)
 	dev->tx_queue_len = 100;
 
 	/* MTU range: 46 - 1500 */
-	dev->min_mtu = QCAFRM_ETHMINMTU;
-	dev->max_mtu = QCAFRM_ETHMAXMTU;
+	dev->min_mtu = QCAFRM_MIN_MTU;
+	dev->max_mtu = QCAFRM_MAX_MTU;
 
 	qca = netdev_priv(dev);
 	memset(qca, 0, sizeof(struct qcaspi));
-- 
2.1.4

[PATCH v5 06/17] net: qca_spi: remove QCASPI_MTU

[Stefan Wahren]

There is no need for an additional MTU define.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_spi.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index a0dbb92..a239ac4 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -69,7 +69,6 @@ static int qcaspi_pluggable = QCASPI_PLUGGABLE_MIN;
 module_param(qcaspi_pluggable, int, 0);
 MODULE_PARM_DESC(qcaspi_pluggable, "Pluggable SPI connection (yes/no).");
 
-#define QCASPI_MTU QCAFRM_MAX_MTU
 #define QCASPI_TX_TIMEOUT (1 * HZ)
 #define QCASPI_QCA7K_REBOOT_TIME_MS 1000
 
@@ -745,7 +744,7 @@ qcaspi_netdev_init(struct net_device *dev)
 {
 	struct qcaspi *qca = netdev_priv(dev);
 
-	dev->mtu = QCASPI_MTU;
+	dev->mtu = QCAFRM_MAX_MTU;
 	dev->type = ARPHRD_ETHER;
 	qca->clkspeed = qcaspi_clkspeed;
 	qca->burst_len = qcaspi_burst_len;
-- 
2.1.4

[PATCH v5 07/17] net: qualcomm: move qcaspi_tx_cmd to qca_spi.c

[Stefan Wahren]

The function qcaspi_tx_cmd() is only called from qca_spi.c. So we better
move it there.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_7k.c  | 24 ------------------------
 drivers/net/ethernet/qualcomm/qca_7k.h  |  1 -
 drivers/net/ethernet/qualcomm/qca_spi.c | 24 ++++++++++++++++++++++++
 3 files changed, 24 insertions(+), 25 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_7k.c b/drivers/net/ethernet/qualcomm/qca_7k.c
index 557d53c..aa90a1d 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k.c
+++ b/drivers/net/ethernet/qualcomm/qca_7k.c
@@ -119,27 +119,3 @@ qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value)
 
 	return ret;
 }
-
-int
-qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd)
-{
-	__be16 tx_data;
-	struct spi_message *msg = &qca->spi_msg1;
-	struct spi_transfer *transfer = &qca->spi_xfer1;
-	int ret;
-
-	tx_data = cpu_to_be16(cmd);
-	transfer->len = sizeof(tx_data);
-	transfer->tx_buf = &tx_data;
-	transfer->rx_buf = NULL;
-
-	ret = spi_sync(qca->spi_dev, msg);
-
-	if (!ret)
-		ret = msg->status;
-
-	if (ret)
-		qcaspi_spi_error(qca);
-
-	return ret;
-}
diff --git a/drivers/net/ethernet/qualcomm/qca_7k.h b/drivers/net/ethernet/qualcomm/qca_7k.h
index 4047f0a..27124c2 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k.h
+++ b/drivers/net/ethernet/qualcomm/qca_7k.h
@@ -67,6 +67,5 @@
 void qcaspi_spi_error(struct qcaspi *qca);
 int qcaspi_read_register(struct qcaspi *qca, u16 reg, u16 *result);
 int qcaspi_write_register(struct qcaspi *qca, u16 reg, u16 value);
-int qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd);
 
 #endif /* _QCA_7K_H */
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index a239ac4..c727357 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -192,6 +192,30 @@ qcaspi_read_legacy(struct qcaspi *qca, u8 *dst, u32 len)
 }
 
 static int
+qcaspi_tx_cmd(struct qcaspi *qca, u16 cmd)
+{
+	__be16 tx_data;
+	struct spi_message *msg = &qca->spi_msg1;
+	struct spi_transfer *transfer = &qca->spi_xfer1;
+	int ret;
+
+	tx_data = cpu_to_be16(cmd);
+	transfer->len = sizeof(tx_data);
+	transfer->tx_buf = &tx_data;
+	transfer->rx_buf = NULL;
+
+	ret = spi_sync(qca->spi_dev, msg);
+
+	if (!ret)
+		ret = msg->status;
+
+	if (ret)
+		qcaspi_spi_error(qca);
+
+	return ret;
+}
+
+static int
 qcaspi_tx_frame(struct qcaspi *qca, struct sk_buff *skb)
 {
 	u32 count;
-- 
2.1.4

[PATCH v5 08/17] net: qca_spi: Clarify MODULE_DESCRIPTION

[Stefan Wahren]

Since this driver is specific to the QCA7000, we should make the module
description more precisely.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_spi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index c727357..deec70f 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -997,7 +997,7 @@ static struct spi_driver qca_spi_driver = {
 };
 module_spi_driver(qca_spi_driver);
 
-MODULE_DESCRIPTION("Qualcomm Atheros SPI Driver");
+MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 SPI Driver");
 MODULE_AUTHOR("Qualcomm Atheros Communications");
 MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
 MODULE_LICENSE("Dual BSD/GPL");
-- 
2.1.4

[PATCH v5 09/17] net: qualcomm: rename qca_framing.c to qca_7k_common.c

[Stefan Wahren]

As preparation for the upcoming UART driver we need a module
which contains common functions for both interfaces. The module
qca_framing is a good candidate but renaming to qca_7k_common would
make it clear.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/Makefile                           | 2 +-
 drivers/net/ethernet/qualcomm/{qca_framing.c => qca_7k_common.c} | 2 +-
 drivers/net/ethernet/qualcomm/{qca_framing.h => qca_7k_common.h} | 0
 drivers/net/ethernet/qualcomm/qca_spi.c                          | 2 +-
 drivers/net/ethernet/qualcomm/qca_spi.h                          | 2 +-
 5 files changed, 4 insertions(+), 4 deletions(-)
 rename drivers/net/ethernet/qualcomm/{qca_framing.c => qca_7k_common.c} (99%)
 rename drivers/net/ethernet/qualcomm/{qca_framing.h => qca_7k_common.h} (100%)

diff --git a/drivers/net/ethernet/qualcomm/Makefile b/drivers/net/ethernet/qualcomm/Makefile
index aacb0a5..5e17bf1 100644
--- a/drivers/net/ethernet/qualcomm/Makefile
+++ b/drivers/net/ethernet/qualcomm/Makefile
@@ -3,6 +3,6 @@
 #
 
 obj-$(CONFIG_QCA7000) += qcaspi.o
-qcaspi-objs := qca_spi.o qca_framing.o qca_7k.o qca_debug.o
+qcaspi-objs := qca_spi.o qca_7k_common.o qca_7k.o qca_debug.o
 
 obj-y += emac/
diff --git a/drivers/net/ethernet/qualcomm/qca_framing.c b/drivers/net/ethernet/qualcomm/qca_7k_common.c
similarity index 99%
rename from drivers/net/ethernet/qualcomm/qca_framing.c
rename to drivers/net/ethernet/qualcomm/qca_7k_common.c
index 2341f2b..6d17fbd 100644
--- a/drivers/net/ethernet/qualcomm/qca_framing.c
+++ b/drivers/net/ethernet/qualcomm/qca_7k_common.c
@@ -23,7 +23,7 @@
 
 #include <linux/kernel.h>
 
-#include "qca_framing.h"
+#include "qca_7k_common.h"
 
 u16
 qcafrm_create_header(u8 *buf, u16 length)
diff --git a/drivers/net/ethernet/qualcomm/qca_framing.h b/drivers/net/ethernet/qualcomm/qca_7k_common.h
similarity index 100%
rename from drivers/net/ethernet/qualcomm/qca_framing.h
rename to drivers/net/ethernet/qualcomm/qca_7k_common.h
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index deec70f..2bc3ba4 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -43,8 +43,8 @@
 #include <linux/types.h>
 
 #include "qca_7k.h"
+#include "qca_7k_common.h"
 #include "qca_debug.h"
-#include "qca_framing.h"
 #include "qca_spi.h"
 
 #define MAX_DMA_BURST_LEN 5000
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.h b/drivers/net/ethernet/qualcomm/qca_spi.h
index 064853d..fc4beb1 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.h
+++ b/drivers/net/ethernet/qualcomm/qca_spi.h
@@ -32,7 +32,7 @@
 #include <linux/spi/spi.h>
 #include <linux/types.h>
 
-#include "qca_framing.h"
+#include "qca_7k_common.h"
 
 #define QCASPI_DRV_VERSION "0.2.7-i"
 #define QCASPI_DRV_NAME    "qcaspi"
-- 
2.1.4

[PATCH v5 10/17] net: qualcomm: prepare frame decoding for UART driver

[Stefan Wahren]

Unfortunately the frame format is not exactly identical between SPI
and UART. In case of SPI there is an additional HW length at the
beginning. So store the initial state to make the decoding state machine
more flexible and easy to extend for UART support.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/qca_7k_common.c | 12 ++++++------
 drivers/net/ethernet/qualcomm/qca_7k_common.h |  8 ++++++--
 drivers/net/ethernet/qualcomm/qca_spi.c       |  2 +-
 3 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/qca_7k_common.c b/drivers/net/ethernet/qualcomm/qca_7k_common.c
index 6d17fbd..0d3daa9 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k_common.c
+++ b/drivers/net/ethernet/qualcomm/qca_7k_common.c
@@ -83,7 +83,7 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 
 		if (recv_byte != 0x00) {
 			/* first two bytes of length must be 0 */
-			handle->state = QCAFRM_HW_LEN0;
+			handle->state = handle->init;
 		}
 		break;
 	case QCAFRM_HW_LEN2:
@@ -97,7 +97,7 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 	case QCAFRM_WAIT_AA4:
 		if (recv_byte != 0xAA) {
 			ret = QCAFRM_NOHEAD;
-			handle->state = QCAFRM_HW_LEN0;
+			handle->state = handle->init;
 		} else {
 			handle->state--;
 		}
@@ -119,7 +119,7 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 		len = handle->offset;
 		if (len > buf_len || len < QCAFRM_MIN_LEN) {
 			ret = QCAFRM_INVLEN;
-			handle->state = QCAFRM_HW_LEN0;
+			handle->state = handle->init;
 		} else {
 			handle->state = (enum qcafrm_state)(len + 1);
 			/* Remaining number of bytes. */
@@ -135,7 +135,7 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 	case QCAFRM_WAIT_551:
 		if (recv_byte != 0x55) {
 			ret = QCAFRM_NOTAIL;
-			handle->state = QCAFRM_HW_LEN0;
+			handle->state = handle->init;
 		} else {
 			handle->state = QCAFRM_WAIT_552;
 		}
@@ -143,11 +143,11 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 	case QCAFRM_WAIT_552:
 		if (recv_byte != 0x55) {
 			ret = QCAFRM_NOTAIL;
-			handle->state = QCAFRM_HW_LEN0;
+			handle->state = handle->init;
 		} else {
 			ret = handle->offset;
 			/* Frame is fully received. */
-			handle->state = QCAFRM_HW_LEN0;
+			handle->state = handle->init;
 		}
 		break;
 	}
diff --git a/drivers/net/ethernet/qualcomm/qca_7k_common.h b/drivers/net/ethernet/qualcomm/qca_7k_common.h
index 5df7c65..07bdd6c 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k_common.h
+++ b/drivers/net/ethernet/qualcomm/qca_7k_common.h
@@ -61,6 +61,7 @@
 #define QCAFRM_ERR_BASE -1000
 
 enum qcafrm_state {
+	/* HW length is only available on SPI */
 	QCAFRM_HW_LEN0 = 0x8000,
 	QCAFRM_HW_LEN1 = QCAFRM_HW_LEN0 - 1,
 	QCAFRM_HW_LEN2 = QCAFRM_HW_LEN1 - 1,
@@ -101,6 +102,8 @@ enum qcafrm_state {
 struct qcafrm_handle {
 	/*  Current decoding state */
 	enum qcafrm_state state;
+	/* Initial state depends on connection type */
+	enum qcafrm_state init;
 
 	/* Offset in buffer (borrowed for length too) */
 	u16 offset;
@@ -113,9 +116,10 @@ u16 qcafrm_create_header(u8 *buf, u16 len);
 
 u16 qcafrm_create_footer(u8 *buf);
 
-static inline void qcafrm_fsm_init(struct qcafrm_handle *handle)
+static inline void qcafrm_fsm_init_spi(struct qcafrm_handle *handle)
 {
-	handle->state = QCAFRM_HW_LEN0;
+	handle->init = QCAFRM_HW_LEN0;
+	handle->state = handle->init;
 }
 
 /*   Gather received bytes and try to extract a full Ethernet frame
diff --git a/drivers/net/ethernet/qualcomm/qca_spi.c b/drivers/net/ethernet/qualcomm/qca_spi.c
index 2bc3ba4..b7073a9 100644
--- a/drivers/net/ethernet/qualcomm/qca_spi.c
+++ b/drivers/net/ethernet/qualcomm/qca_spi.c
@@ -637,7 +637,7 @@ qcaspi_netdev_open(struct net_device *dev)
 	qca->intr_req = 1;
 	qca->intr_svc = 0;
 	qca->sync = QCASPI_SYNC_UNKNOWN;
-	qcafrm_fsm_init(&qca->frm_handle);
+	qcafrm_fsm_init_spi(&qca->frm_handle);
 
 	qca->spi_thread = kthread_run((void *)qcaspi_spi_thread,
 				      qca, "%s", dev->name);
-- 
2.1.4

[PATCH v5 11/17] net: qualcomm: make qca_7k_common a separate kernel module

[Stefan Wahren]

In order to share common functions between QCA7000 SPI and UART protocol
driver the qca_7k_common needs to be a separate kernel module.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/Kconfig         |  8 +++++++-
 drivers/net/ethernet/qualcomm/Makefile        |  5 +++--
 drivers/net/ethernet/qualcomm/qca_7k_common.c | 10 ++++++++++
 3 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/qualcomm/Kconfig b/drivers/net/ethernet/qualcomm/Kconfig
index d7720bf..b4c369d 100644
--- a/drivers/net/ethernet/qualcomm/Kconfig
+++ b/drivers/net/ethernet/qualcomm/Kconfig
@@ -16,7 +16,13 @@ config NET_VENDOR_QUALCOMM
 if NET_VENDOR_QUALCOMM
 
 config QCA7000
-	tristate "Qualcomm Atheros QCA7000 support"
+	tristate
+	help
+	  This enables support for the Qualcomm Atheros QCA7000.
+
+config QCA7000_SPI
+	tristate "Qualcomm Atheros QCA7000 SPI support"
+	select QCA7000
 	depends on SPI_MASTER && OF
 	---help---
 	  This SPI protocol driver supports the Qualcomm Atheros QCA7000.
diff --git a/drivers/net/ethernet/qualcomm/Makefile b/drivers/net/ethernet/qualcomm/Makefile
index 5e17bf1..65556ca 100644
--- a/drivers/net/ethernet/qualcomm/Makefile
+++ b/drivers/net/ethernet/qualcomm/Makefile
@@ -2,7 +2,8 @@
 # Makefile for the Qualcomm network device drivers.
 #
 
-obj-$(CONFIG_QCA7000) += qcaspi.o
-qcaspi-objs := qca_spi.o qca_7k_common.o qca_7k.o qca_debug.o
+obj-$(CONFIG_QCA7000) += qca_7k_common.o
+obj-$(CONFIG_QCA7000_SPI) += qcaspi.o
+qcaspi-objs := qca_7k.o qca_debug.o qca_spi.o
 
 obj-y += emac/
diff --git a/drivers/net/ethernet/qualcomm/qca_7k_common.c b/drivers/net/ethernet/qualcomm/qca_7k_common.c
index 0d3daa9..6b511f0 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k_common.c
+++ b/drivers/net/ethernet/qualcomm/qca_7k_common.c
@@ -21,7 +21,9 @@
  *   by an atheros frame while transmitted over a serial channel;
  */
 
+#include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/module.h>
 
 #include "qca_7k_common.h"
 
@@ -46,6 +48,7 @@ qcafrm_create_header(u8 *buf, u16 length)
 
 	return QCAFRM_HEADER_LEN;
 }
+EXPORT_SYMBOL_GPL(qcafrm_create_header);
 
 u16
 qcafrm_create_footer(u8 *buf)
@@ -57,6 +60,7 @@ qcafrm_create_footer(u8 *buf)
 	buf[1] = 0x55;
 	return QCAFRM_FOOTER_LEN;
 }
+EXPORT_SYMBOL_GPL(qcafrm_create_footer);
 
 /*   Gather received bytes and try to extract a full ethernet frame by
  *   following a simple state machine.
@@ -154,3 +158,9 @@ qcafrm_fsm_decode(struct qcafrm_handle *handle, u8 *buf, u16 buf_len, u8 recv_by
 
 	return ret;
 }
+EXPORT_SYMBOL_GPL(qcafrm_fsm_decode);
+
+MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 common");
+MODULE_AUTHOR("Qualcomm Atheros Communications");
+MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
+MODULE_LICENSE("Dual BSD/GPL");
-- 
2.1.4

[PATCH v5 12/17] dt-bindings: qca7000-spi: Rework binding

[Stefan Wahren]

In preparation for the QCA7000 UART binding rework the binding document.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 .../devicetree/bindings/net/qca-qca7000-spi.txt    | 49 +++++++++++++---------
 1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/qca-qca7000-spi.txt b/Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
index c74989c..a37f656 100644
--- a/Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
+++ b/Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
@@ -1,29 +1,38 @@
-* Qualcomm QCA7000 (Ethernet over SPI protocol)
+* Qualcomm QCA7000
 
-Note: The QCA7000 is useable as a SPI device. In this case it must be defined
-as a child of a SPI master in the device tree.
+The QCA7000 is a serial-to-powerline bridge with a host interface which could
+be configured either as SPI or UART slave. This configuration is done by
+the QCA7000 firmware.
+
+(a) Ethernet over SPI
+
+In order to use the QCA7000 as SPI device it must be defined as a child of a
+SPI master in the device tree.
 
 Required properties:
-- compatible : Should be "qca,qca7000"
-- reg : Should specify the SPI chip select
-- interrupts : The first cell should specify the index of the source interrupt
-  and the second cell should specify the trigger type as rising edge
-- spi-cpha : Must be set
-- spi-cpol: Must be set
+- compatible	    : Should be "qca,qca7000"
+- reg		    : Should specify the SPI chip select
+- interrupts	    : The first cell should specify the index of the source
+		      interrupt and the second cell should specify the trigger
+		      type as rising edge
+- spi-cpha	    : Must be set
+- spi-cpol	    : Must be set
 
 Optional properties:
-- interrupt-parent : Specify the pHandle of the source interrupt
+- interrupt-parent  : Specify the pHandle of the source interrupt
 - spi-max-frequency : Maximum frequency of the SPI bus the chip can operate at.
-  Numbers smaller than 1000000 or greater than 16000000 are invalid. Missing
-  the property will set the SPI frequency to 8000000 Hertz.
-- local-mac-address: 6 bytes, MAC address
-- qca,legacy-mode : Set the SPI data transfer of the QCA7000 to legacy mode.
-  In this mode the SPI master must toggle the chip select between each data
-  word. In burst mode these gaps aren't necessary, which is faster.
-  This setting depends on how the QCA7000 is setup via GPIO pin strapping.
-  If the property is missing the driver defaults to burst mode.
-
-Example:
+		      Numbers smaller than 1000000 or greater than 16000000
+		      are invalid. Missing the property will set the SPI
+		      frequency to 8000000 Hertz.
+- local-mac-address : see ./ethernet.txt
+- qca,legacy-mode   : Set the SPI data transfer of the QCA7000 to legacy mode.
+		      In this mode the SPI master must toggle the chip select
+		      between each data word. In burst mode these gaps aren't
+		      necessary, which is faster. This setting depends on how
+		      the QCA7000 is setup via GPIO pin strapping. If the
+		      property is missing the driver defaults to burst mode.
+
+SPI Example:
 
 /* Freescale i.MX28 SPI master*/
 ssp2: spi@80014000 {
-- 
2.1.4

[PATCH v5 13/17] dt-bindings: qca7000: rename binding

[Stefan Wahren]

Before we can merge the QCA7000 UART binding the document needs to be
renamed.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 .../devicetree/bindings/net/{qca-qca7000-spi.txt => qca-qca7000.txt}      | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 rename Documentation/devicetree/bindings/net/{qca-qca7000-spi.txt => qca-qca7000.txt} (100%)

diff --git a/Documentation/devicetree/bindings/net/qca-qca7000-spi.txt b/Documentation/devicetree/bindings/net/qca-qca7000.txt
similarity index 100%
rename from Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
rename to Documentation/devicetree/bindings/net/qca-qca7000.txt
-- 
2.1.4

Re: [PATCH v5 13/17] dt-bindings: qca7000: rename binding

[Michael Heimpold]

Hi,

Am Mittwoch, 10. Mai 2017, 10:53:24 CEST schrieb Stefan Wahren:
> Before we can merge the QCA7000 UART binding the document needs to be
> renamed.
> 
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> ---
>  .../devicetree/bindings/net/{qca-qca7000-spi.txt => qca-qca7000.txt}      |
> 0 1 file changed, 0 insertions(+), 0 deletions(-)
>  rename Documentation/devicetree/bindings/net/{qca-qca7000-spi.txt =>
> qca-qca7000.txt} (100%)
> 
> diff --git a/Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
> b/Documentation/devicetree/bindings/net/qca-qca7000.txt similarity index
> 100%
> rename from Documentation/devicetree/bindings/net/qca-qca7000-spi.txt
> rename to Documentation/devicetree/bindings/net/qca-qca7000.txt

I was told here [1], that it is prefered when the filename matchs the
compatible string, so using "qca,qca7000.txt" should be better.

Regards,
Michael


[1]
https://www.spinics.net/lists/devicetree/msg124088.html

[PATCH v5 14/17] dt-bindings: slave-device: add current-speed property

[Stefan Wahren]

This adds a new DT property to define the current baud rate of the
slave device.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 Documentation/devicetree/bindings/serial/slave-device.txt | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/Documentation/devicetree/bindings/serial/slave-device.txt b/Documentation/devicetree/bindings/serial/slave-device.txt
index f660379..40110e0 100644
--- a/Documentation/devicetree/bindings/serial/slave-device.txt
+++ b/Documentation/devicetree/bindings/serial/slave-device.txt
@@ -21,6 +21,15 @@ Optional Properties:
 		  can support. For example, a particular board has some signal
 		  quality issue or the host processor can't support higher
 		  baud rates.
+- current-speed	: The current baud rate the device operates at. This should
+		  only be present in case a driver has no chance to know
+		  the baud rate of the slave device.
+		  Examples:
+		    * device supports auto-baud
+		    * the rate is setup by a bootloader and there is no
+		      way to reset the device
+		    * device baud rate is configured by its firmware but
+		      there is no way to request the actual settings
 
 Example:
 
-- 
2.1.4

Re: [PATCH v5 14/17] dt-bindings: slave-device: add current-speed property

[Rob Herring]

On Wed, May 10, 2017 at 10:53:25AM +0200, Stefan Wahren wrote:
> This adds a new DT property to define the current baud rate of the
> slave device.
> 
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> ---
>  Documentation/devicetree/bindings/serial/slave-device.txt | 9 +++++++++
>  1 file changed, 9 insertions(+)

Reviewed-by: Rob Herring <robh@kernel.org>

[PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Stefan Wahren]

This merges the serdev binding for the QCA7000 UART driver (Ethernet over
UART) into the existing document.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 .../devicetree/bindings/net/qca-qca7000.txt        | 32 ++++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt b/Documentation/devicetree/bindings/net/qca-qca7000.txt
index a37f656..08364c3 100644
--- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
+++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
@@ -54,3 +54,35 @@ ssp2: spi@80014000 {
 		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
 	};
 };
+
+(b) Ethernet over UART
+
+In order to use the QCA7000 as UART slave it must be defined as a child of a
+UART master in the device tree. It is possible to preconfigure the UART
+settings of the QCA7000 firmware, but it's not possible to change them during
+runtime.
+
+Required properties:
+- compatible        : Should be "qca,qca7000-uart"
+
+Optional properties:
+- local-mac-address : see ./ethernet.txt
+- current-speed     : current baud rate of QCA7000 which defaults to 115200
+		      if absent, see also ../serial/slave-device.txt
+
+UART Example:
+
+/* Freescale i.MX28 UART */
+auart0: serial@8006a000 {
+	compatible = "fsl,imx28-auart", "fsl,imx23-auart";
+	reg = <0x8006a000 0x2000>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&auart0_2pins_a>;
+	status = "okay";
+
+	qca7000: ethernet {
+		compatible = "qca,qca7000-uart";
+		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
+		current-speed = <38400>;
+	};
+};
-- 
2.1.4

Re: [PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Michael Heimpold]

Hi,

Am Mittwoch, 10. Mai 2017, 10:53:26 CEST schrieb Stefan Wahren:
> This merges the serdev binding for the QCA7000 UART driver (Ethernet over
> UART) into the existing document.
> 
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> ---
>  .../devicetree/bindings/net/qca-qca7000.txt        | 32
> ++++++++++++++++++++++ 1 file changed, 32 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt
> b/Documentation/devicetree/bindings/net/qca-qca7000.txt index
> a37f656..08364c3 100644
> --- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
> +++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
> @@ -54,3 +54,35 @@ ssp2: spi@80014000 {
>  		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
>  	};
>  };
> +
> +(b) Ethernet over UART
> +
> +In order to use the QCA7000 as UART slave it must be defined as a child of
> a +UART master in the device tree. It is possible to preconfigure the UART
> +settings of the QCA7000 firmware, but it's not possible to change them
> during +runtime.
> +
> +Required properties:
> +- compatible        : Should be "qca,qca7000-uart"

I already discussed this with Stefan off-list a little bit, but I would like
to bring this to a broader audience: I'm not sure whether the compatible 
should contain the "-uart" suffix, because the hardware chip is the very same
QCA7000 chip which can also be used with SPI protocol.
The only difference is the loaded firmware within the chip which can either
speak SPI or UART protocol (but not both at the same time - due to shared 
pins). So the hardware design decides which interface type is used.

At the moment, this patch series adds a dedicated driver for the UART 
protocol, in parallel to the existing SPI driver. So a different compatible
string is needed here to match against the new driver.

An alternative approach would be to re-use the existing compatible string
"qca,qca7000" for both, the SPI and UART protocol, because a "smarter" 
(combined) driver would detect which protocol to use. For example the driver 
could check for spi-cpha and/or spi-cpol which are required for SPI protocol: 
if these exists the driver could assume that SPI must be used, if both are 
missing then UART protocol should be used.
(This way it would not be necessary to check whether the node is a child of
a SPI or UART master node - but maybe this is even easier - I don't know)

Or in shorter words: my concern is that while "qca7000-uart" describes the 
hardware, it's too closely coupled to the driver implementation. Having
some feedback of the experts would be nice :-)

Thanks,
Michael

> +
> +Optional properties:
> +- local-mac-address : see ./ethernet.txt
> +- current-speed     : current baud rate of QCA7000 which defaults to 115200
> +		      if absent, see also ../serial/slave-device.txt
> +
> +UART Example:
> +
> +/* Freescale i.MX28 UART */
> +auart0: serial@8006a000 {
> +	compatible = "fsl,imx28-auart", "fsl,imx23-auart";
> +	reg = <0x8006a000 0x2000>;
> +	pinctrl-names = "default";
> +	pinctrl-0 = <&auart0_2pins_a>;
> +	status = "okay";
> +
> +	qca7000: ethernet {
> +		compatible = "qca,qca7000-uart";
> +		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
> +		current-speed = <38400>;
> +	};
> +};

Re: [PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Jakub Kicinski]

On Thu, 11 May 2017 21:12:22 +0200, Michael Heimpold wrote:
> Am Mittwoch, 10. Mai 2017, 10:53:26 CEST schrieb Stefan Wahren:
> > This merges the serdev binding for the QCA7000 UART driver (Ethernet over
> > UART) into the existing document.
> > 
> > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> > ---
> >  .../devicetree/bindings/net/qca-qca7000.txt        | 32
> > ++++++++++++++++++++++ 1 file changed, 32 insertions(+)
> > 
> > diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt
> > b/Documentation/devicetree/bindings/net/qca-qca7000.txt index
> > a37f656..08364c3 100644
> > --- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
> > +++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
> > @@ -54,3 +54,35 @@ ssp2: spi@80014000 {
> >  		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
> >  	};
> >  };
> > +
> > +(b) Ethernet over UART
> > +
> > +In order to use the QCA7000 as UART slave it must be defined as a child of
> > a +UART master in the device tree. It is possible to preconfigure the UART
> > +settings of the QCA7000 firmware, but it's not possible to change them
> > during +runtime.
> > +
> > +Required properties:
> > +- compatible        : Should be "qca,qca7000-uart"  
> 
> I already discussed this with Stefan off-list a little bit, but I would like
> to bring this to a broader audience: I'm not sure whether the compatible 
> should contain the "-uart" suffix, because the hardware chip is the very same
> QCA7000 chip which can also be used with SPI protocol.
> The only difference is the loaded firmware within the chip which can either
> speak SPI or UART protocol (but not both at the same time - due to shared 
> pins). So the hardware design decides which interface type is used.
> 
> At the moment, this patch series adds a dedicated driver for the UART 
> protocol, in parallel to the existing SPI driver. So a different compatible
> string is needed here to match against the new driver.
> 
> An alternative approach would be to re-use the existing compatible string
> "qca,qca7000" for both, the SPI and UART protocol, because a "smarter" 
> (combined) driver would detect which protocol to use. For example the driver 
> could check for spi-cpha and/or spi-cpol which are required for SPI protocol: 
> if these exists the driver could assume that SPI must be used, if both are 
> missing then UART protocol should be used.
> (This way it would not be necessary to check whether the node is a child of
> a SPI or UART master node - but maybe this is even easier - I don't know)
> 
> Or in shorter words: my concern is that while "qca7000-uart" describes the 
> hardware, it's too closely coupled to the driver implementation. Having
> some feedback of the experts would be nice :-)

I'm no expert, but devices which can do both I2C and SPI are quite
common, and they usually have the same compatible string for both
buses.

Re: [PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Michael Heimpold]

Hi,

Zitat von Jakub Kicinski <kubakici@wp.pl>:

> On Thu, 11 May 2017 21:12:22 +0200, Michael Heimpold wrote:
>> Am Mittwoch, 10. Mai 2017, 10:53:26 CEST schrieb Stefan Wahren:
>> > This merges the serdev binding for the QCA7000 UART driver (Ethernet over
>> > UART) into the existing document.
>> >
>> > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
>> > ---
>> >  .../devicetree/bindings/net/qca-qca7000.txt        | 32
>> > ++++++++++++++++++++++ 1 file changed, 32 insertions(+)
>> >
>> > diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt
>> > b/Documentation/devicetree/bindings/net/qca-qca7000.txt index
>> > a37f656..08364c3 100644
>> > --- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
>> > +++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
>> > @@ -54,3 +54,35 @@ ssp2: spi@80014000 {
>> >  		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
>> >  	};
>> >  };
>> > +
>> > +(b) Ethernet over UART
>> > +
>> > +In order to use the QCA7000 as UART slave it must be defined as  
>> a child of
>> > a +UART master in the device tree. It is possible to preconfigure the UART
>> > +settings of the QCA7000 firmware, but it's not possible to change them
>> > during +runtime.
>> > +
>> > +Required properties:
>> > +- compatible        : Should be "qca,qca7000-uart"
>>
>> I already discussed this with Stefan off-list a little bit, but I would like
>> to bring this to a broader audience: I'm not sure whether the compatible
>> should contain the "-uart" suffix, because the hardware chip is the  
>> very same
>> QCA7000 chip which can also be used with SPI protocol.
>> The only difference is the loaded firmware within the chip which can either
>> speak SPI or UART protocol (but not both at the same time - due to shared
>> pins). So the hardware design decides which interface type is used.
>>
>> At the moment, this patch series adds a dedicated driver for the UART
>> protocol, in parallel to the existing SPI driver. So a different compatible
>> string is needed here to match against the new driver.
>>
>> An alternative approach would be to re-use the existing compatible string
>> "qca,qca7000" for both, the SPI and UART protocol, because a "smarter"
>> (combined) driver would detect which protocol to use. For example the driver
>> could check for spi-cpha and/or spi-cpol which are required for SPI  
>> protocol:
>> if these exists the driver could assume that SPI must be used, if both are
>> missing then UART protocol should be used.
>> (This way it would not be necessary to check whether the node is a child of
>> a SPI or UART master node - but maybe this is even easier - I don't know)
>>
>> Or in shorter words: my concern is that while "qca7000-uart" describes the
>> hardware, it's too closely coupled to the driver implementation. Having
>> some feedback of the experts would be nice :-)
>
> I'm no expert, but devices which can do both I2C and SPI are quite
> common, and they usually have the same compatible string for both
> buses.

do you have an example driver at hand? I only found GPIO mcp23s08 driver,
which can handle both I2C and SPI chips, but there are different compatible
strings used to distinguish several chip models.

Regards,
Michael

Re: [PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Jakub Kicinski]

On Fri, 12 May 2017 06:15:52 +0000, Michael Heimpold wrote:
> Hi,
> 
> Zitat von Jakub Kicinski <kubakici@wp.pl>:
> 
> > On Thu, 11 May 2017 21:12:22 +0200, Michael Heimpold wrote:  
> >> Am Mittwoch, 10. Mai 2017, 10:53:26 CEST schrieb Stefan Wahren:  
> >> > This merges the serdev binding for the QCA7000 UART driver (Ethernet over
> >> > UART) into the existing document.
> >> >
> >> > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> >> > ---
> >> >  .../devicetree/bindings/net/qca-qca7000.txt        | 32
> >> > ++++++++++++++++++++++ 1 file changed, 32 insertions(+)
> >> >
> >> > diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt
> >> > b/Documentation/devicetree/bindings/net/qca-qca7000.txt index
> >> > a37f656..08364c3 100644
> >> > --- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
> >> > +++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
> >> > @@ -54,3 +54,35 @@ ssp2: spi@80014000 {
> >> >  		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
> >> >  	};
> >> >  };
> >> > +
> >> > +(b) Ethernet over UART
> >> > +
> >> > +In order to use the QCA7000 as UART slave it must be defined as    
> >> a child of  
> >> > a +UART master in the device tree. It is possible to preconfigure the UART
> >> > +settings of the QCA7000 firmware, but it's not possible to change them
> >> > during +runtime.
> >> > +
> >> > +Required properties:
> >> > +- compatible        : Should be "qca,qca7000-uart"  
> >>
> >> I already discussed this with Stefan off-list a little bit, but I would like
> >> to bring this to a broader audience: I'm not sure whether the compatible
> >> should contain the "-uart" suffix, because the hardware chip is the  
> >> very same
> >> QCA7000 chip which can also be used with SPI protocol.
> >> The only difference is the loaded firmware within the chip which can either
> >> speak SPI or UART protocol (but not both at the same time - due to shared
> >> pins). So the hardware design decides which interface type is used.
> >>
> >> At the moment, this patch series adds a dedicated driver for the UART
> >> protocol, in parallel to the existing SPI driver. So a different compatible
> >> string is needed here to match against the new driver.
> >>
> >> An alternative approach would be to re-use the existing compatible string
> >> "qca,qca7000" for both, the SPI and UART protocol, because a "smarter"
> >> (combined) driver would detect which protocol to use. For example the driver
> >> could check for spi-cpha and/or spi-cpol which are required for SPI  
> >> protocol:
> >> if these exists the driver could assume that SPI must be used, if both are
> >> missing then UART protocol should be used.
> >> (This way it would not be necessary to check whether the node is a child of
> >> a SPI or UART master node - but maybe this is even easier - I don't know)
> >>
> >> Or in shorter words: my concern is that while "qca7000-uart" describes the
> >> hardware, it's too closely coupled to the driver implementation. Having
> >> some feedback of the experts would be nice :-)  
> >
> > I'm no expert, but devices which can do both I2C and SPI are quite
> > common, and they usually have the same compatible string for both
> > buses.  
> 
> do you have an example driver at hand? I only found GPIO mcp23s08 driver,
> which can handle both I2C and SPI chips, but there are different compatible
> strings used to distinguish several chip models.

I think drivers/tty/serial/sc16is7xx.c has the same strings, and some
Kconfig magic to work when either bus is enabled in .config.

Quick grep shows there are couple more potential ones to look at:

$ find . -name Kconfig | xargs grep -n 'SPI_MASTER.* I2C' 
./drivers/tty/serial/Kconfig:1208:        depends on (SPI_MASTER && !I2C) || I2C
./drivers/mfd/Kconfig:327:	depends on (SPI_MASTER || I2C)
./drivers/iio/dac/Kconfig:10:	depends on (SPI_MASTER && I2C!=m) || I2C
./drivers/iio/dac/Kconfig:34:	depends on (SPI_MASTER && I2C!=m) || I2C
./drivers/iio/dac/Kconfig:57:	depends on (SPI_MASTER && I2C!=m) || I2C
./drivers/gpio/Kconfig:1231:	depends on (SPI_MASTER && !I2C) || I2C
$ find . -name Kconfig | xargs grep -n 'I2C.*||.*SPI_MASTER' 
./drivers/mfd/Kconfig:1094:	depends on (I2C=y || SPI_MASTER=y)
./drivers/iio/gyro/Kconfig:55:	depends on (I2C || SPI_MASTER)
./drivers/iio/gyro/Kconfig:107:	depends on (I2C || SPI_MASTER) && SYSFS
./drivers/iio/accel/Kconfig:153:	depends on (I2C || SPI_MASTER) && SYSFS
./drivers/iio/pressure/Kconfig:20:	depends on (I2C || SPI_MASTER)
./drivers/iio/pressure/Kconfig:161:	depends on (I2C || SPI_MASTER) && SYSFS
./drivers/iio/magnetometer/Kconfig:118:	depends on (I2C || SPI_MASTER) && SYSFS

drivers/mfd/mc13xxx-*.c seems to have the same strings.  The iio/dac drivers
don't support DT but do share names.  The MCP GPIO chip you mention indeed has
different product names based on the bus it's made for (0 vs s in the middle 
of the name), so I gather less relevant case?  drivers/iio/pressure/bmp280-*.c 
has the same strings, if I'm looking correctly... I didn't look at the others.

Re: [PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Stefan Wahren]

Hi Rob,

Am 12.05.2017 um 08:43 schrieb Jakub Kicinski:
> On Fri, 12 May 2017 06:15:52 +0000, Michael Heimpold wrote:
>> Hi,
>>
>> Zitat von Jakub Kicinski <kubakici@wp.pl>:
>>
>>> On Thu, 11 May 2017 21:12:22 +0200, Michael Heimpold wrote:  
>>>> Am Mittwoch, 10. Mai 2017, 10:53:26 CEST schrieb Stefan Wahren:  
>>>>> This merges the serdev binding for the QCA7000 UART driver (Ethernet over
>>>>> UART) into the existing document.
>>>>>
>>>>> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
>>>>> ---
>>>>>  .../devicetree/bindings/net/qca-qca7000.txt        | 32
>>>>> ++++++++++++++++++++++ 1 file changed, 32 insertions(+)
>>>>>
>>>>> diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt
>>>>> b/Documentation/devicetree/bindings/net/qca-qca7000.txt index
>>>>> a37f656..08364c3 100644
>>>>> --- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
>>>>> +++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
>>>>> @@ -54,3 +54,35 @@ ssp2: spi@80014000 {
>>>>>  		local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
>>>>>  	};
>>>>>  };
>>>>> +
>>>>> +(b) Ethernet over UART
>>>>> +
>>>>> +In order to use the QCA7000 as UART slave it must be defined as    
>>>> a child of  
>>>>> a +UART master in the device tree. It is possible to preconfigure the UART
>>>>> +settings of the QCA7000 firmware, but it's not possible to change them
>>>>> during +runtime.
>>>>> +
>>>>> +Required properties:
>>>>> +- compatible        : Should be "qca,qca7000-uart"  
>>>> I already discussed this with Stefan off-list a little bit, but I would like
>>>> to bring this to a broader audience: I'm not sure whether the compatible
>>>> should contain the "-uart" suffix, because the hardware chip is the  
>>>> very same
>>>> QCA7000 chip which can also be used with SPI protocol.
>>>> The only difference is the loaded firmware within the chip which can either
>>>> speak SPI or UART protocol (but not both at the same time - due to shared
>>>> pins). So the hardware design decides which interface type is used.
>>>>
>>>> At the moment, this patch series adds a dedicated driver for the UART
>>>> protocol, in parallel to the existing SPI driver. So a different compatible
>>>> string is needed here to match against the new driver.
>>>>
>>>> An alternative approach would be to re-use the existing compatible string
>>>> "qca,qca7000" for both, the SPI and UART protocol, because a "smarter"
>>>> (combined) driver would detect which protocol to use. For example the driver
>>>> could check for spi-cpha and/or spi-cpol which are required for SPI  
>>>> protocol:
>>>> if these exists the driver could assume that SPI must be used, if both are
>>>> missing then UART protocol should be used.
>>>> (This way it would not be necessary to check whether the node is a child of
>>>> a SPI or UART master node - but maybe this is even easier - I don't know)
>>>>
>>>> Or in shorter words: my concern is that while "qca7000-uart" describes the
>>>> hardware, it's too closely coupled to the driver implementation. Having
>>>> some feedback of the experts would be nice :-)  
>>> I'm no expert, but devices which can do both I2C and SPI are quite
>>> common, and they usually have the same compatible string for both
>>> buses.  
>> do you have an example driver at hand? I only found GPIO mcp23s08 driver,
>> which can handle both I2C and SPI chips, but there are different compatible
>> strings used to distinguish several chip models.
> I think drivers/tty/serial/sc16is7xx.c has the same strings, and some
> Kconfig magic to work when either bus is enabled in .config.
>
> Quick grep shows there are couple more potential ones to look at:
>
> $ find . -name Kconfig | xargs grep -n 'SPI_MASTER.* I2C' 
> ./drivers/tty/serial/Kconfig:1208:        depends on (SPI_MASTER && !I2C) || I2C
> ./drivers/mfd/Kconfig:327:	depends on (SPI_MASTER || I2C)
> ./drivers/iio/dac/Kconfig:10:	depends on (SPI_MASTER && I2C!=m) || I2C
> ./drivers/iio/dac/Kconfig:34:	depends on (SPI_MASTER && I2C!=m) || I2C
> ./drivers/iio/dac/Kconfig:57:	depends on (SPI_MASTER && I2C!=m) || I2C
> ./drivers/gpio/Kconfig:1231:	depends on (SPI_MASTER && !I2C) || I2C
> $ find . -name Kconfig | xargs grep -n 'I2C.*||.*SPI_MASTER' 
> ./drivers/mfd/Kconfig:1094:	depends on (I2C=y || SPI_MASTER=y)
> ./drivers/iio/gyro/Kconfig:55:	depends on (I2C || SPI_MASTER)
> ./drivers/iio/gyro/Kconfig:107:	depends on (I2C || SPI_MASTER) && SYSFS
> ./drivers/iio/accel/Kconfig:153:	depends on (I2C || SPI_MASTER) && SYSFS
> ./drivers/iio/pressure/Kconfig:20:	depends on (I2C || SPI_MASTER)
> ./drivers/iio/pressure/Kconfig:161:	depends on (I2C || SPI_MASTER) && SYSFS
> ./drivers/iio/magnetometer/Kconfig:118:	depends on (I2C || SPI_MASTER) && SYSFS
>
> drivers/mfd/mc13xxx-*.c seems to have the same strings.  The iio/dac drivers
> don't support DT but do share names.  The MCP GPIO chip you mention indeed has
> different product names based on the bus it's made for (0 vs s in the middle 
> of the name), so I gather less relevant case?  drivers/iio/pressure/bmp280-*.c 
> has the same strings, if I'm looking correctly... I didn't look at the others.

are you okay with the suggestion to use the compatible "qca,qca7000" for
both drivers?

Should we mark "qca,qca7000-spi" as deprecated?

Regards
Stefan

Re: [PATCH v5 15/17] dt-bindings: qca7000: append UART interface to binding

[Rob Herring]

On Fri, May 19, 2017 at 2:13 AM, Stefan Wahren <stefan.wahren@i2se.com> wrote:
> Hi Rob,
>
> Am 12.05.2017 um 08:43 schrieb Jakub Kicinski:
>> On Fri, 12 May 2017 06:15:52 +0000, Michael Heimpold wrote:
>>> Hi,
>>>
>>> Zitat von Jakub Kicinski <kubakici@wp.pl>:
>>>
>>>> On Thu, 11 May 2017 21:12:22 +0200, Michael Heimpold wrote:
>>>>> Am Mittwoch, 10. Mai 2017, 10:53:26 CEST schrieb Stefan Wahren:
>>>>>> This merges the serdev binding for the QCA7000 UART driver (Ethernet over
>>>>>> UART) into the existing document.
>>>>>>
>>>>>> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
>>>>>> ---
>>>>>>  .../devicetree/bindings/net/qca-qca7000.txt        | 32
>>>>>> ++++++++++++++++++++++ 1 file changed, 32 insertions(+)
>>>>>>
>>>>>> diff --git a/Documentation/devicetree/bindings/net/qca-qca7000.txt
>>>>>> b/Documentation/devicetree/bindings/net/qca-qca7000.txt index
>>>>>> a37f656..08364c3 100644
>>>>>> --- a/Documentation/devicetree/bindings/net/qca-qca7000.txt
>>>>>> +++ b/Documentation/devicetree/bindings/net/qca-qca7000.txt
>>>>>> @@ -54,3 +54,35 @@ ssp2: spi@80014000 {
>>>>>>           local-mac-address = [ A0 B0 C0 D0 E0 F0 ];
>>>>>>   };
>>>>>>  };
>>>>>> +
>>>>>> +(b) Ethernet over UART
>>>>>> +
>>>>>> +In order to use the QCA7000 as UART slave it must be defined as
>>>>> a child of
>>>>>> a +UART master in the device tree. It is possible to preconfigure the UART
>>>>>> +settings of the QCA7000 firmware, but it's not possible to change them
>>>>>> during +runtime.
>>>>>> +
>>>>>> +Required properties:
>>>>>> +- compatible        : Should be "qca,qca7000-uart"
>>>>> I already discussed this with Stefan off-list a little bit, but I would like
>>>>> to bring this to a broader audience: I'm not sure whether the compatible
>>>>> should contain the "-uart" suffix, because the hardware chip is the
>>>>> very same
>>>>> QCA7000 chip which can also be used with SPI protocol.
>>>>> The only difference is the loaded firmware within the chip which can either
>>>>> speak SPI or UART protocol (but not both at the same time - due to shared
>>>>> pins). So the hardware design decides which interface type is used.
>>>>>
>>>>> At the moment, this patch series adds a dedicated driver for the UART
>>>>> protocol, in parallel to the existing SPI driver. So a different compatible
>>>>> string is needed here to match against the new driver.
>>>>>
>>>>> An alternative approach would be to re-use the existing compatible string
>>>>> "qca,qca7000" for both, the SPI and UART protocol, because a "smarter"
>>>>> (combined) driver would detect which protocol to use. For example the driver
>>>>> could check for spi-cpha and/or spi-cpol which are required for SPI
>>>>> protocol:
>>>>> if these exists the driver could assume that SPI must be used, if both are
>>>>> missing then UART protocol should be used.
>>>>> (This way it would not be necessary to check whether the node is a child of
>>>>> a SPI or UART master node - but maybe this is even easier - I don't know)
>>>>>
>>>>> Or in shorter words: my concern is that while "qca7000-uart" describes the
>>>>> hardware, it's too closely coupled to the driver implementation. Having
>>>>> some feedback of the experts would be nice :-)
>>>> I'm no expert, but devices which can do both I2C and SPI are quite
>>>> common, and they usually have the same compatible string for both
>>>> buses.
>>> do you have an example driver at hand? I only found GPIO mcp23s08 driver,
>>> which can handle both I2C and SPI chips, but there are different compatible
>>> strings used to distinguish several chip models.
>> I think drivers/tty/serial/sc16is7xx.c has the same strings, and some
>> Kconfig magic to work when either bus is enabled in .config.
>>
>> Quick grep shows there are couple more potential ones to look at:
>>
>> $ find . -name Kconfig | xargs grep -n 'SPI_MASTER.* I2C'
>> ./drivers/tty/serial/Kconfig:1208:        depends on (SPI_MASTER && !I2C) || I2C
>> ./drivers/mfd/Kconfig:327:    depends on (SPI_MASTER || I2C)
>> ./drivers/iio/dac/Kconfig:10: depends on (SPI_MASTER && I2C!=m) || I2C
>> ./drivers/iio/dac/Kconfig:34: depends on (SPI_MASTER && I2C!=m) || I2C
>> ./drivers/iio/dac/Kconfig:57: depends on (SPI_MASTER && I2C!=m) || I2C
>> ./drivers/gpio/Kconfig:1231:  depends on (SPI_MASTER && !I2C) || I2C
>> $ find . -name Kconfig | xargs grep -n 'I2C.*||.*SPI_MASTER'
>> ./drivers/mfd/Kconfig:1094:   depends on (I2C=y || SPI_MASTER=y)
>> ./drivers/iio/gyro/Kconfig:55:        depends on (I2C || SPI_MASTER)
>> ./drivers/iio/gyro/Kconfig:107:       depends on (I2C || SPI_MASTER) && SYSFS
>> ./drivers/iio/accel/Kconfig:153:      depends on (I2C || SPI_MASTER) && SYSFS
>> ./drivers/iio/pressure/Kconfig:20:    depends on (I2C || SPI_MASTER)
>> ./drivers/iio/pressure/Kconfig:161:   depends on (I2C || SPI_MASTER) && SYSFS
>> ./drivers/iio/magnetometer/Kconfig:118:       depends on (I2C || SPI_MASTER) && SYSFS
>>
>> drivers/mfd/mc13xxx-*.c seems to have the same strings.  The iio/dac drivers
>> don't support DT but do share names.  The MCP GPIO chip you mention indeed has
>> different product names based on the bus it's made for (0 vs s in the middle
>> of the name), so I gather less relevant case?  drivers/iio/pressure/bmp280-*.c
>> has the same strings, if I'm looking correctly... I didn't look at the others.
>
> are you okay with the suggestion to use the compatible "qca,qca7000" for
> both drivers?

I believe I said I was fine either way.

> Should we mark "qca,qca7000-spi" as deprecated?

Yes.

Rob

[PATCH v5 16/17] tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrate

[Stefan Wahren]

Instead of returning the requested baudrate, we better return the
actual one because it isn't always the same.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Rob Herring <robh@kernel.org>
---
 drivers/tty/serdev/serdev-ttyport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c
index 487c88f..2cfdf34 100644
--- a/drivers/tty/serdev/serdev-ttyport.c
+++ b/drivers/tty/serdev/serdev-ttyport.c
@@ -151,7 +151,7 @@ static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigne
 
 	/* tty_set_termios() return not checked as it is always 0 */
 	tty_set_termios(tty, &ktermios);
-	return speed;
+	return ktermios.c_ospeed;
 }
 
 static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
-- 
2.1.4

Re: [PATCH v5 16/17] tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrate

[Stefan Wahren]

Hi Greg,

Am 10.05.2017 um 10:53 schrieb Stefan Wahren:
> Instead of returning the requested baudrate, we better return the
> actual one because it isn't always the same.
>
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> Acked-by: Rob Herring <robh@kernel.org>
> ---
>  drivers/tty/serdev/serdev-ttyport.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c
> index 487c88f..2cfdf34 100644
> --- a/drivers/tty/serdev/serdev-ttyport.c
> +++ b/drivers/tty/serdev/serdev-ttyport.c
> @@ -151,7 +151,7 @@ static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigne
>  
>  	/* tty_set_termios() return not checked as it is always 0 */
>  	tty_set_termios(tty, &ktermios);
> -	return speed;
> +	return ktermios.c_ospeed;
>  }
>  
>  static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)

there is no dependency to this series. I would be happy if this could be
applied, so i don't have to carry it for the next version.

Thanks
Stefan

Re: [PATCH v5 16/17] tty: serdev-ttyport: return actual baudrate from ttyport_set_baudrate

[Greg Kroah-Hartman]

On Wed, May 17, 2017 at 01:58:05PM +0200, Stefan Wahren wrote:
> Hi Greg,
> 
> Am 10.05.2017 um 10:53 schrieb Stefan Wahren:
> > Instead of returning the requested baudrate, we better return the
> > actual one because it isn't always the same.
> >
> > Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> > Acked-by: Rob Herring <robh@kernel.org>
> > ---
> >  drivers/tty/serdev/serdev-ttyport.c | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/tty/serdev/serdev-ttyport.c b/drivers/tty/serdev/serdev-ttyport.c
> > index 487c88f..2cfdf34 100644
> > --- a/drivers/tty/serdev/serdev-ttyport.c
> > +++ b/drivers/tty/serdev/serdev-ttyport.c
> > @@ -151,7 +151,7 @@ static unsigned int ttyport_set_baudrate(struct serdev_controller *ctrl, unsigne
> >  
> >  	/* tty_set_termios() return not checked as it is always 0 */
> >  	tty_set_termios(tty, &ktermios);
> > -	return speed;
> > +	return ktermios.c_ospeed;
> >  }
> >  
> >  static void ttyport_set_flow_control(struct serdev_controller *ctrl, bool enable)
> 
> there is no dependency to this series. I would be happy if this could be
> applied, so i don't have to carry it for the next version.

Ok, I'll take it now.

thanks,

greg k-h

[PATCH v5 17/17] net: qualcomm: add QCA7000 UART driver

[Stefan Wahren]

This patch adds the Ethernet over UART driver for the
Qualcomm QCA7000 HomePlug GreenPHY.

Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
---
 drivers/net/ethernet/qualcomm/Kconfig         |  16 +
 drivers/net/ethernet/qualcomm/Makefile        |   2 +
 drivers/net/ethernet/qualcomm/qca_7k_common.h |   6 +
 drivers/net/ethernet/qualcomm/qca_uart.c      | 423 ++++++++++++++++++++++++++
 4 files changed, 447 insertions(+)
 create mode 100644 drivers/net/ethernet/qualcomm/qca_uart.c

diff --git a/drivers/net/ethernet/qualcomm/Kconfig b/drivers/net/ethernet/qualcomm/Kconfig
index b4c369d..877675a 100644
--- a/drivers/net/ethernet/qualcomm/Kconfig
+++ b/drivers/net/ethernet/qualcomm/Kconfig
@@ -30,6 +30,22 @@ config QCA7000_SPI
 	  To compile this driver as a module, choose M here. The module
 	  will be called qcaspi.
 
+config QCA7000_UART
+	tristate "Qualcomm Atheros QCA7000 UART support"
+	select QCA7000
+	depends on SERIAL_DEV_BUS && OF
+	---help---
+	  This UART protocol driver supports the Qualcomm Atheros QCA7000.
+
+	  Currently the driver assumes these device UART settings:
+	    Data bits: 8
+	    Parity: None
+	    Stop bits: 1
+	    Flow control: None
+
+	  To compile this driver as a module, choose M here. The module
+	  will be called qcauart.
+
 config QCOM_EMAC
 	tristate "Qualcomm Technologies, Inc. EMAC Gigabit Ethernet support"
 	depends on HAS_DMA && HAS_IOMEM
diff --git a/drivers/net/ethernet/qualcomm/Makefile b/drivers/net/ethernet/qualcomm/Makefile
index 65556ca..92fa7c4 100644
--- a/drivers/net/ethernet/qualcomm/Makefile
+++ b/drivers/net/ethernet/qualcomm/Makefile
@@ -5,5 +5,7 @@
 obj-$(CONFIG_QCA7000) += qca_7k_common.o
 obj-$(CONFIG_QCA7000_SPI) += qcaspi.o
 qcaspi-objs := qca_7k.o qca_debug.o qca_spi.o
+obj-$(CONFIG_QCA7000_UART) += qcauart.o
+qcauart-objs := qca_uart.o
 
 obj-y += emac/
diff --git a/drivers/net/ethernet/qualcomm/qca_7k_common.h b/drivers/net/ethernet/qualcomm/qca_7k_common.h
index 07bdd6c..928554f 100644
--- a/drivers/net/ethernet/qualcomm/qca_7k_common.h
+++ b/drivers/net/ethernet/qualcomm/qca_7k_common.h
@@ -122,6 +122,12 @@ static inline void qcafrm_fsm_init_spi(struct qcafrm_handle *handle)
 	handle->state = handle->init;
 }
 
+static inline void qcafrm_fsm_init_uart(struct qcafrm_handle *handle)
+{
+	handle->init = QCAFRM_WAIT_AA1;
+	handle->state = handle->init;
+}
+
 /*   Gather received bytes and try to extract a full Ethernet frame
  *   by following a simple state machine.
  *
diff --git a/drivers/net/ethernet/qualcomm/qca_uart.c b/drivers/net/ethernet/qualcomm/qca_uart.c
new file mode 100644
index 0000000..1f6514c
--- /dev/null
+++ b/drivers/net/ethernet/qualcomm/qca_uart.c
@@ -0,0 +1,423 @@
+/*
+ *   Copyright (c) 2011, 2012, Qualcomm Atheros Communications Inc.
+ *   Copyright (c) 2017, I2SE GmbH
+ *
+ *   Permission to use, copy, modify, and/or distribute this software
+ *   for any purpose with or without fee is hereby granted, provided
+ *   that the above copyright notice and this permission notice appear
+ *   in all copies.
+ *
+ *   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+ *   WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+ *   WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL
+ *   THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+ *   CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ *   LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+ *   NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ *   CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/*   This module implements the Qualcomm Atheros UART protocol for
+ *   kernel-based UART device; it is essentially an Ethernet-to-UART
+ *   serial converter;
+ */
+
+#include <linux/errno.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/if_ether.h>
+#include <linux/init.h>
+#include <linux/jiffies.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_net.h>
+#include <linux/sched.h>
+#include <linux/serdev.h>
+#include <linux/skbuff.h>
+#include <linux/types.h>
+
+#include "qca_7k_common.h"
+
+#define QCAUART_DRV_VERSION "0.1.0"
+#define QCAUART_DRV_NAME "qcauart"
+#define QCAUART_TX_TIMEOUT (1 * HZ)
+
+struct qcauart {
+	struct net_device *net_dev;
+	spinlock_t lock;			/* transmit lock */
+	struct work_struct tx_work;		/* Flushes transmit buffer   */
+
+	struct serdev_device *serdev;
+	struct qcafrm_handle frm_handle;
+	struct sk_buff *rx_skb;
+
+	unsigned char *tx_head;			/* pointer to next XMIT byte */
+	int tx_left;				/* bytes left in XMIT queue  */
+	unsigned char *tx_buffer;
+};
+
+static int
+qca_tty_receive(struct serdev_device *serdev, const unsigned char *data,
+		size_t count)
+{
+	struct qcauart *qca = serdev_device_get_drvdata(serdev);
+	struct net_device *netdev = qca->net_dev;
+	struct net_device_stats *n_stats = &netdev->stats;
+	size_t i;
+
+	if (!qca->rx_skb) {
+		qca->rx_skb = netdev_alloc_skb_ip_align(netdev,
+							netdev->mtu +
+							VLAN_ETH_HLEN);
+		if (!qca->rx_skb) {
+			n_stats->rx_errors++;
+			n_stats->rx_dropped++;
+			return 0;
+		}
+	}
+
+	for (i = 0; i < count; i++) {
+		s32 retcode;
+
+		retcode = qcafrm_fsm_decode(&qca->frm_handle,
+					    qca->rx_skb->data,
+					    skb_tailroom(qca->rx_skb),
+					    data[i]);
+
+		switch (retcode) {
+		case QCAFRM_GATHER:
+		case QCAFRM_NOHEAD:
+			break;
+		case QCAFRM_NOTAIL:
+			netdev_dbg(netdev, "recv: no RX tail\n");
+			n_stats->rx_errors++;
+			n_stats->rx_dropped++;
+			break;
+		case QCAFRM_INVLEN:
+			netdev_dbg(netdev, "recv: invalid RX length\n");
+			n_stats->rx_errors++;
+			n_stats->rx_dropped++;
+			break;
+		default:
+			n_stats->rx_packets++;
+			n_stats->rx_bytes += retcode;
+			skb_put(qca->rx_skb, retcode);
+			qca->rx_skb->protocol = eth_type_trans(
+						qca->rx_skb, qca->rx_skb->dev);
+			qca->rx_skb->ip_summed = CHECKSUM_UNNECESSARY;
+			netif_rx_ni(qca->rx_skb);
+			qca->rx_skb = netdev_alloc_skb_ip_align(netdev,
+								netdev->mtu +
+								VLAN_ETH_HLEN);
+			if (!qca->rx_skb) {
+				netdev_dbg(netdev, "recv: out of RX resources\n");
+				n_stats->rx_errors++;
+				return i;
+			}
+		}
+	}
+
+	return i;
+}
+
+/* Write out any remaining transmit buffer. Scheduled when tty is writable */
+static void qcauart_transmit(struct work_struct *work)
+{
+	struct qcauart *qca = container_of(work, struct qcauart, tx_work);
+	struct net_device_stats *n_stats = &qca->net_dev->stats;
+	int written;
+
+	spin_lock_bh(&qca->lock);
+
+	/* First make sure we're connected. */
+	if (!netif_running(qca->net_dev)) {
+		spin_unlock_bh(&qca->lock);
+		return;
+	}
+
+	if (qca->tx_left <= 0)  {
+		/* Now serial buffer is almost free & we can start
+		 * transmission of another packet
+		 */
+		n_stats->tx_packets++;
+		spin_unlock_bh(&qca->lock);
+		netif_wake_queue(qca->net_dev);
+		return;
+	}
+
+	written = serdev_device_write_buf(qca->serdev, qca->tx_head,
+					  qca->tx_left);
+	if (written > 0) {
+		qca->tx_left -= written;
+		qca->tx_head += written;
+	}
+	spin_unlock_bh(&qca->lock);
+}
+
+/* Called by the driver when there's room for more data.
+ * Schedule the transmit.
+ */
+static void qca_tty_wakeup(struct serdev_device *serdev)
+{
+	struct qcauart *qca = serdev_device_get_drvdata(serdev);
+
+	schedule_work(&qca->tx_work);
+}
+
+static struct serdev_device_ops qca_serdev_ops = {
+	.receive_buf = qca_tty_receive,
+	.write_wakeup = qca_tty_wakeup,
+};
+
+static int qcauart_netdev_open(struct net_device *dev)
+{
+	struct qcauart *qca = netdev_priv(dev);
+
+	netif_start_queue(qca->net_dev);
+
+	return 0;
+}
+
+static int qcauart_netdev_close(struct net_device *dev)
+{
+	struct qcauart *qca = netdev_priv(dev);
+
+	spin_lock_bh(&qca->lock);
+	netif_stop_queue(dev);
+	qca->tx_left = 0;
+	spin_unlock_bh(&qca->lock);
+
+	return 0;
+}
+
+static netdev_tx_t
+qcauart_netdev_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct net_device_stats *n_stats = &dev->stats;
+	struct qcauart *qca = netdev_priv(dev);
+	u8 pad_len = 0;
+	int written;
+	u8 *pos;
+
+	spin_lock(&qca->lock);
+
+	WARN_ON(qca->tx_left);
+
+	if (!netif_running(dev))  {
+		spin_unlock(&qca->lock);
+		netdev_warn(qca->net_dev, "xmit: iface is down\n");
+		goto out;
+	}
+
+	pos = qca->tx_buffer;
+
+	if (skb->len < QCAFRM_MIN_LEN)
+		pad_len = QCAFRM_MIN_LEN - skb->len;
+
+	pos += qcafrm_create_header(pos, skb->len + pad_len);
+
+	memcpy(pos, skb->data, skb->len);
+	pos += skb->len;
+
+	if (pad_len) {
+		memset(pos, 0, pad_len);
+		pos += pad_len;
+	}
+
+	pos += qcafrm_create_footer(pos);
+
+	netif_stop_queue(qca->net_dev);
+
+	written = serdev_device_write_buf(qca->serdev, qca->tx_buffer,
+					  pos - qca->tx_buffer);
+	if (written > 0) {
+		qca->tx_left = (pos - qca->tx_buffer) - written;
+		qca->tx_head = qca->tx_buffer + written;
+		n_stats->tx_bytes += written;
+	}
+	spin_unlock(&qca->lock);
+
+	netif_trans_update(dev);
+out:
+	kfree_skb(skb);
+	return NETDEV_TX_OK;
+}
+
+static void qcauart_netdev_tx_timeout(struct net_device *dev)
+{
+	struct qcauart *qca = netdev_priv(dev);
+
+	netdev_info(qca->net_dev, "Transmit timeout at %ld, latency %ld\n",
+		    jiffies, dev_trans_start(dev));
+	dev->stats.tx_errors++;
+	dev->stats.tx_dropped++;
+}
+
+static int qcauart_netdev_init(struct net_device *dev)
+{
+	struct qcauart *qca = netdev_priv(dev);
+	size_t len;
+
+	/* Finish setting up the device info. */
+	dev->mtu = QCAFRM_MAX_MTU;
+	dev->type = ARPHRD_ETHER;
+
+	qca->rx_skb = netdev_alloc_skb_ip_align(qca->net_dev,
+						qca->net_dev->mtu +
+						VLAN_ETH_HLEN);
+	if (!qca->rx_skb)
+		return -ENOBUFS;
+
+	len = QCAFRM_HEADER_LEN + QCAFRM_MAX_LEN + QCAFRM_FOOTER_LEN;
+	qca->tx_buffer = kmalloc(len, GFP_KERNEL);
+	if (!qca->tx_buffer)
+		return -ENOBUFS;
+
+	return 0;
+}
+
+static void qcauart_netdev_uninit(struct net_device *dev)
+{
+	struct qcauart *qca = netdev_priv(dev);
+
+	kfree(qca->tx_buffer);
+	if (qca->rx_skb)
+		dev_kfree_skb(qca->rx_skb);
+}
+
+static const struct net_device_ops qcauart_netdev_ops = {
+	.ndo_init = qcauart_netdev_init,
+	.ndo_uninit = qcauart_netdev_uninit,
+	.ndo_open = qcauart_netdev_open,
+	.ndo_stop = qcauart_netdev_close,
+	.ndo_start_xmit = qcauart_netdev_xmit,
+	.ndo_set_mac_address = eth_mac_addr,
+	.ndo_tx_timeout = qcauart_netdev_tx_timeout,
+	.ndo_validate_addr = eth_validate_addr,
+};
+
+static void qcauart_netdev_setup(struct net_device *dev)
+{
+	struct qcauart *qca;
+
+	dev->netdev_ops = &qcauart_netdev_ops;
+	dev->watchdog_timeo = QCAUART_TX_TIMEOUT;
+	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
+	dev->tx_queue_len = 100;
+
+	/* MTU range: 46 - 1500 */
+	dev->min_mtu = QCAFRM_MIN_MTU;
+	dev->max_mtu = QCAFRM_MAX_MTU;
+
+	qca = netdev_priv(dev);
+	memset(qca, 0, sizeof(struct qcauart));
+}
+
+static const struct of_device_id qca_uart_of_match[] = {
+	{
+	 .compatible = "qca,qca7000-uart",
+	},
+	{}
+};
+MODULE_DEVICE_TABLE(of, qca_uart_of_match);
+
+static int qca_uart_probe(struct serdev_device *serdev)
+{
+	struct net_device *qcauart_dev = alloc_etherdev(sizeof(struct qcauart));
+	struct qcauart *qca;
+	const char *mac;
+	u32 speed = 115200;
+	int ret;
+
+	if (!qcauart_dev)
+		return -ENOMEM;
+
+	qcauart_netdev_setup(qcauart_dev);
+
+	qca = netdev_priv(qcauart_dev);
+	if (!qca) {
+		pr_err("qca_uart: Fail to retrieve private structure\n");
+		ret = -ENOMEM;
+		goto free;
+	}
+	qca->net_dev = qcauart_dev;
+	qca->serdev = serdev;
+	qcafrm_fsm_init_uart(&qca->frm_handle);
+
+	spin_lock_init(&qca->lock);
+	INIT_WORK(&qca->tx_work, qcauart_transmit);
+
+	of_property_read_u32(serdev->dev.of_node, "current-speed", &speed);
+
+	mac = of_get_mac_address(serdev->dev.of_node);
+
+	if (mac)
+		ether_addr_copy(qca->net_dev->dev_addr, mac);
+
+	if (!is_valid_ether_addr(qca->net_dev->dev_addr)) {
+		eth_hw_addr_random(qca->net_dev);
+		dev_info(&serdev->dev, "Using random MAC address: %pM\n",
+			 qca->net_dev->dev_addr);
+	}
+
+	netif_carrier_on(qca->net_dev);
+	serdev_device_set_drvdata(serdev, qca);
+	serdev_device_set_client_ops(serdev, &qca_serdev_ops);
+
+	ret = serdev_device_open(serdev);
+	if (ret) {
+		dev_err(&serdev->dev, "Unable to open device %s\n",
+			qcauart_dev->name);
+		goto free;
+	}
+
+	speed = serdev_device_set_baudrate(serdev, speed);
+	dev_info(&serdev->dev, "Using baudrate: %u\n", speed);
+
+	serdev_device_set_flow_control(serdev, false);
+
+	ret = register_netdev(qcauart_dev);
+	if (ret) {
+		dev_err(&serdev->dev, "Unable to register net device %s\n",
+			qcauart_dev->name);
+		goto free;
+	}
+
+	return 0;
+
+free:
+	free_netdev(qcauart_dev);
+	return ret;
+}
+
+static void qca_uart_remove(struct serdev_device *serdev)
+{
+	struct qcauart *qca = serdev_device_get_drvdata(serdev);
+
+	/* Flush any pending characters in the driver. */
+	serdev_device_close(serdev);
+
+	netif_carrier_off(qca->net_dev);
+	unregister_netdev(qca->net_dev);
+	free_netdev(qca->net_dev);
+}
+
+static struct serdev_device_driver qca_uart_driver = {
+	.probe = qca_uart_probe,
+	.remove = qca_uart_remove,
+	.driver = {
+		.name = QCAUART_DRV_NAME,
+		.of_match_table = of_match_ptr(qca_uart_of_match),
+	},
+};
+
+module_serdev_device_driver(qca_uart_driver);
+
+MODULE_DESCRIPTION("Qualcomm Atheros QCA7000 UART Driver");
+MODULE_AUTHOR("Qualcomm Atheros Communications");
+MODULE_AUTHOR("Stefan Wahren <stefan.wahren@i2se.com>");
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_VERSION(QCAUART_DRV_VERSION);
-- 
2.1.4

Re: [PATCH v5 17/17] net: qualcomm: add QCA7000 UART driver

[Lino Sanfilippo]

Hi,

On 10.05.2017 10:53, Stefan Wahren wrote:

> +static int qcauart_netdev_init(struct net_device *dev)
> +{
> +	struct qcauart *qca = netdev_priv(dev);
> +	size_t len;
> +
> +	/* Finish setting up the device info. */
> +	dev->mtu = QCAFRM_MAX_MTU;
> +	dev->type = ARPHRD_ETHER;
> +
> +	qca->rx_skb = netdev_alloc_skb_ip_align(qca->net_dev,
> +						qca->net_dev->mtu +
> +						VLAN_ETH_HLEN);
> +	if (!qca->rx_skb)
> +		return -ENOBUFS;
> +
> +	len = QCAFRM_HEADER_LEN + QCAFRM_MAX_LEN + QCAFRM_FOOTER_LEN;
> +	qca->tx_buffer = kmalloc(len, GFP_KERNEL);
> +	if (!qca->tx_buffer)
> +		return -ENOBUFS;

Freeing the rx_skb is missing here.

> +
> +static void qcauart_netdev_setup(struct net_device *dev)
> +{
> +	struct qcauart *qca;
> +
> +	dev->netdev_ops = &qcauart_netdev_ops;
> +	dev->watchdog_timeo = QCAUART_TX_TIMEOUT;
> +	dev->priv_flags &= ~IFF_TX_SKB_SHARING;
> +	dev->tx_queue_len = 100;
> +
> +	/* MTU range: 46 - 1500 */
> +	dev->min_mtu = QCAFRM_MIN_MTU;
> +	dev->max_mtu = QCAFRM_MAX_MTU;
> +
> +	qca = netdev_priv(dev);
> +	memset(qca, 0, sizeof(struct qcauart));

Zeroing the private data is not necessary since it is already done
at device allocation.


> +
> +static int qca_uart_probe(struct serdev_device *serdev)
> +{
> +	struct net_device *qcauart_dev = alloc_etherdev(sizeof(struct qcauart));
> +	struct qcauart *qca;
> +	const char *mac;
> +	u32 speed = 115200;
> +	int ret;
> +
> +	if (!qcauart_dev)
> +		return -ENOMEM;
> +
> +	qcauart_netdev_setup(qcauart_dev);
> +
> +	qca = netdev_priv(qcauart_dev);
> +	if (!qca) {
> +		pr_err("qca_uart: Fail to retrieve private structure\n");
> +		ret = -ENOMEM;
> +		goto free;
> +	}
> +	qca->net_dev = qcauart_dev;
> +	qca->serdev = serdev;
> +	qcafrm_fsm_init_uart(&qca->frm_handle);
> +
> +	spin_lock_init(&qca->lock);
> +	INIT_WORK(&qca->tx_work, qcauart_transmit);
> +
> +	of_property_read_u32(serdev->dev.of_node, "current-speed", &speed);
> +
> +	mac = of_get_mac_address(serdev->dev.of_node);
> +
> +	if (mac)
> +		ether_addr_copy(qca->net_dev->dev_addr, mac);
> +
> +	if (!is_valid_ether_addr(qca->net_dev->dev_addr)) {
> +		eth_hw_addr_random(qca->net_dev);
> +		dev_info(&serdev->dev, "Using random MAC address: %pM\n",
> +			 qca->net_dev->dev_addr);
> +	}
> +
> +	netif_carrier_on(qca->net_dev);
> +	serdev_device_set_drvdata(serdev, qca);
> +	serdev_device_set_client_ops(serdev, &qca_serdev_ops);
> +
> +	ret = serdev_device_open(serdev);
> +	if (ret) {
> +		dev_err(&serdev->dev, "Unable to open device %s\n",
> +			qcauart_dev->name);
> +		goto free;
> +	}
> +
> +	speed = serdev_device_set_baudrate(serdev, speed);
> +	dev_info(&serdev->dev, "Using baudrate: %u\n", speed);
> +
> +	serdev_device_set_flow_control(serdev, false);
> +
> +	ret = register_netdev(qcauart_dev);
> +	if (ret) {
> +		dev_err(&serdev->dev, "Unable to register net device %s\n",
> +			qcauart_dev->name);

	serdev_device_close() ?

> +		goto free;
> +	}
> +
> +	return 0;
> +
> +free:
> +	free_netdev(qcauart_dev);
> +	return ret;
> +}
> +
> +static void qca_uart_remove(struct serdev_device *serdev)
> +{
> +	struct qcauart *qca = serdev_device_get_drvdata(serdev);

	Here you should make sure that the tx_work is not running/pending any
	more (e.g by calling cancel_delayed_work_sync()).

> +	/* Flush any pending characters in the driver. */
> +	serdev_device_close(serdev);
> +
> +	netif_carrier_off(qca->net_dev);
> +	unregister_netdev(qca->net_dev);
> +	free_netdev(qca->net_dev);
> +}

Regards,
Lino