[PATCH 1/2] can: kvaser_usb: kvaser_usb_leaf: Fix CAN clock frequency regression

[Jimmy Assarsson <extja@kvaser.com>]

The firmware of M32C based Leaf devices expects bittiming parameters
calculated for 16MHz clock.
Since we use the actual clock frequency of the device, the device may end
up with wrong bittiming parameters, depending on user requested parameters.

This regression affects M32C based Leaf devices with non-16MHz clock.

Fixes: fb12797ab1fe ("can: kvaser_usb: get CAN clock frequency from device")
Cc: stable@vger.kernel.org
Signed-off-by: Jimmy Assarsson <extja@kvaser.com>
---
 drivers/net/can/usb/kvaser_usb/kvaser_usb.h   |  4 +++
 .../net/can/usb/kvaser_usb/kvaser_usb_core.c  | 20 +++++++++++----
 .../net/can/usb/kvaser_usb/kvaser_usb_leaf.c  | 25 ++++++++++++-------
 3 files changed, 35 insertions(+), 14 deletions(-)

diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb.h b/drivers/net/can/usb/kvaser_usb/kvaser_usb.h
index 3a49257f9fa6..cb588228d7a1 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb.h
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb.h
@@ -44,6 +44,9 @@
 #define KVASER_USB_CAP_EXT_CAP			0x02
 #define KVASER_USB_HYDRA_CAP_EXT_CMD		0x04
 
+/* Quriks */
+#define KVASER_USB_QUIRK_IGNORE_CLK_FREQ BIT(0)
+
 struct kvaser_usb_dev_cfg;
 
 enum kvaser_usb_leaf_family {
@@ -65,6 +68,7 @@ struct kvaser_usb_dev_card_data_hydra {
 struct kvaser_usb_dev_card_data {
 	u32 ctrlmode_supported;
 	u32 capabilities;
+	u32 quirks;
 	union {
 		struct {
 			enum kvaser_usb_leaf_family family;
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
index e67658b53d02..5880e9719c9d 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_core.c
@@ -94,10 +94,14 @@
 
 static inline bool kvaser_is_leaf(const struct usb_device_id *id)
 {
-	return (id->idProduct >= USB_LEAF_DEVEL_PRODUCT_ID &&
-		id->idProduct <= USB_CAN_R_PRODUCT_ID) ||
-		(id->idProduct >= USB_LEAF_LITE_V2_PRODUCT_ID &&
-		 id->idProduct <= USB_LEAF_PRODUCT_ID_END);
+	return id->idProduct >= USB_LEAF_DEVEL_PRODUCT_ID &&
+	       id->idProduct <= USB_CAN_R_PRODUCT_ID;
+}
+
+static inline bool kvaser_is_leafimx(const struct usb_device_id *id)
+{
+	return id->idProduct >= USB_LEAF_LITE_V2_PRODUCT_ID &&
+	       id->idProduct <= USB_LEAF_PRODUCT_ID_END;
 }
 
 static inline bool kvaser_is_usbcan(const struct usb_device_id *id)
@@ -113,7 +117,7 @@ static inline bool kvaser_is_hydra(const struct usb_device_id *id)
 }
 
 static const struct usb_device_id kvaser_usb_table[] = {
-	/* Leaf USB product IDs */
+	/* Leaf M32C USB product IDs */
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_DEVEL_PRODUCT_ID) },
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_PRODUCT_ID) },
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_PRO_PRODUCT_ID),
@@ -161,6 +165,8 @@ static const struct usb_device_id kvaser_usb_table[] = {
 		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_CAN_R_PRODUCT_ID),
 		.driver_info = KVASER_USB_HAS_TXRX_ERRORS },
+
+	/* Leaf i.MX28 USB product IDs */
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LITE_V2_PRODUCT_ID) },
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_MINI_PCIE_HS_PRODUCT_ID) },
 	{ USB_DEVICE(KVASER_VENDOR_ID, USB_LEAF_LIGHT_HS_V2_OEM_PRODUCT_ID) },
@@ -737,6 +743,10 @@ static int kvaser_usb_probe(struct usb_interface *intf,
 	if (kvaser_is_leaf(id)) {
 		dev->card_data.leaf.family = KVASER_LEAF;
 		dev->ops = &kvaser_usb_leaf_dev_ops;
+		dev->card_data.quirks = KVASER_USB_QUIRK_IGNORE_CLK_FREQ;
+	} else if (kvaser_is_leafimx(id)) {
+		dev->card_data.leaf.family = KVASER_LEAF;
+		dev->ops = &kvaser_usb_leaf_dev_ops;
 	} else if (kvaser_is_usbcan(id)) {
 		dev->card_data.leaf.family = KVASER_USBCAN;
 		dev->ops = &kvaser_usb_leaf_dev_ops;
diff --git a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
index c805b999c543..68c698e3b2b2 100644
--- a/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
+++ b/drivers/net/can/usb/kvaser_usb/kvaser_usb_leaf.c
@@ -524,16 +524,23 @@ static void kvaser_usb_leaf_get_software_info_leaf(struct kvaser_usb *dev,
 	dev->fw_version = le32_to_cpu(softinfo->fw_version);
 	dev->max_tx_urbs = le16_to_cpu(softinfo->max_outstanding_tx);
 
-	switch (sw_options & KVASER_USB_LEAF_SWOPTION_FREQ_MASK) {
-	case KVASER_USB_LEAF_SWOPTION_FREQ_16_MHZ_CLK:
+	if (dev->card_data.quirks & KVASER_USB_QUIRK_IGNORE_CLK_FREQ) {
+		/* Firmware expects bittiming parameters calculated for 16MHz
+		 * clock, regardless of the actual clock
+		 */
 		dev->cfg = &kvaser_usb_leaf_dev_cfg_16mhz;
-		break;
-	case KVASER_USB_LEAF_SWOPTION_FREQ_24_MHZ_CLK:
-		dev->cfg = &kvaser_usb_leaf_dev_cfg_24mhz;
-		break;
-	case KVASER_USB_LEAF_SWOPTION_FREQ_32_MHZ_CLK:
-		dev->cfg = &kvaser_usb_leaf_dev_cfg_32mhz;
-		break;
+	} else {
+		switch (sw_options & KVASER_USB_LEAF_SWOPTION_FREQ_MASK) {
+		case KVASER_USB_LEAF_SWOPTION_FREQ_16_MHZ_CLK:
+			dev->cfg = &kvaser_usb_leaf_dev_cfg_16mhz;
+			break;
+		case KVASER_USB_LEAF_SWOPTION_FREQ_24_MHZ_CLK:
+			dev->cfg = &kvaser_usb_leaf_dev_cfg_24mhz;
+			break;
+		case KVASER_USB_LEAF_SWOPTION_FREQ_32_MHZ_CLK:
+			dev->cfg = &kvaser_usb_leaf_dev_cfg_32mhz;
+			break;
+		}
 	}
 }
 
-- 
2.36.1