From ea8b33bde76c8fcef347b9b9cf15649fe41a5a6e Mon Sep 17 00:00:00 2001 From: Stephane Grosjean Date: Fri, 6 Dec 2019 16:38:03 +0100 Subject: [PATCH] can: pcan_usb: add support of rxerr/txerr counters This patch adds the support of the rx/tx errors CAN counters to the driver of the PCAN-USB PC-CAN interface from PEAK-System GmbH. The PCAN-USB is capable of giving back the values of the rx/tx errors counters, to provide more details and statistics to the linux-can layer. Getting these values allows the driver to better tune CAN_ERR_CRTL_TX_xxx and CAN_ERR_CRTL_RX_xxx bits in case of the interface enters any CAN_STATE_ERROR_xxx state. Signed-off-by: Stephane Grosjean Link: https://lore.kernel.org/r/20191206153803.17725-3-s.grosjean@peak-system.com Signed-off-by: Marc Kleine-Budde --- drivers/net/can/usb/peak_usb/pcan_usb.c | 133 ++++++++++++++++++++++++++++---- 1 file changed, 117 insertions(+), 16 deletions(-) diff --git a/drivers/net/can/usb/peak_usb/pcan_usb.c b/drivers/net/can/usb/peak_usb/pcan_usb.c index 76468250cabf..63bd2ed96697 100644 --- a/drivers/net/can/usb/peak_usb/pcan_usb.c +++ b/drivers/net/can/usb/peak_usb/pcan_usb.c @@ -41,6 +41,7 @@ MODULE_SUPPORTED_DEVICE("PEAK-System PCAN-USB adapter"); #define PCAN_USB_CMD_SN 6 #define PCAN_USB_CMD_REGISTER 9 #define PCAN_USB_CMD_EXT_VCC 10 +#define PCAN_USB_CMD_ERR_FR 11 /* PCAN_USB_CMD_SET_BUS number arg */ #define PCAN_USB_BUS_XCVER 2 @@ -82,6 +83,10 @@ MODULE_SUPPORTED_DEVICE("PEAK-System PCAN-USB adapter"); #define PCAN_USB_ERROR_QOVR 0x40 #define PCAN_USB_ERROR_TXQFULL 0x80 +#define PCAN_USB_ERROR_BUS (PCAN_USB_ERROR_BUS_LIGHT | \ + PCAN_USB_ERROR_BUS_HEAVY | \ + PCAN_USB_ERROR_BUS_OFF) + /* SJA1000 modes */ #define SJA1000_MODE_NORMAL 0x00 #define SJA1000_MODE_INIT 0x01 @@ -101,11 +106,25 @@ MODULE_SUPPORTED_DEVICE("PEAK-System PCAN-USB adapter"); #define PCAN_USB_REC_TS 4 #define PCAN_USB_REC_BUSEVT 5 +/* CAN bus events notifications selection mask */ +#define PCAN_USB_ERR_RXERR 0x02 /* ask for rxerr counter */ +#define PCAN_USB_ERR_TXERR 0x04 /* ask for txerr counter */ + +/* This mask generates an usb packet each time the state of the bus changes. + * In other words, its interest is to know which side among rx and tx is + * responsible of the change of the bus state. + */ +#define PCAN_USB_BERR_MASK (PCAN_USB_ERR_RXERR | PCAN_USB_ERR_TXERR) + +/* identify bus event packets with rx/tx error counters */ +#define PCAN_USB_ERR_CNT 0x80 + /* private to PCAN-USB adapter */ struct pcan_usb { struct peak_usb_device dev; struct peak_time_ref time_ref; struct timer_list restart_timer; + struct can_berr_counter bec; }; /* incoming message context for decoding */ @@ -212,6 +231,16 @@ static int pcan_usb_set_silent(struct peak_usb_device *dev, u8 onoff) PCAN_USB_BUS_SILENT_MODE, args); } +/* send the cmd to be notified from bus errors */ +static int pcan_usb_set_err_frame(struct peak_usb_device *dev, u8 err_mask) +{ + u8 args[PCAN_USB_CMD_ARGS_LEN] = { + [0] = err_mask, + }; + + return pcan_usb_send_cmd(dev, PCAN_USB_CMD_ERR_FR, PCAN_USB_SET, args); +} + static int pcan_usb_set_ext_vcc(struct peak_usb_device *dev, u8 onoff) { u8 args[PCAN_USB_CMD_ARGS_LEN] = { @@ -445,7 +474,7 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n, new_state = CAN_STATE_BUS_OFF; break; } - if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) { + if (n & ~PCAN_USB_ERROR_BUS) { /* * trick to bypass next comparison and process other * errors @@ -469,7 +498,7 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n, new_state = CAN_STATE_ERROR_WARNING; break; } - if (n & (PCAN_USB_ERROR_RXQOVR | PCAN_USB_ERROR_QOVR)) { + if (n & ~PCAN_USB_ERROR_BUS) { /* * trick to bypass next comparison and process other * errors @@ -508,29 +537,50 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n, case CAN_STATE_ERROR_PASSIVE: cf->can_id |= CAN_ERR_CRTL; - cf->data[1] |= CAN_ERR_CRTL_TX_PASSIVE | - CAN_ERR_CRTL_RX_PASSIVE; + cf->data[1] = (mc->pdev->bec.txerr > mc->pdev->bec.rxerr) ? + CAN_ERR_CRTL_TX_PASSIVE : + CAN_ERR_CRTL_RX_PASSIVE; + cf->data[6] = mc->pdev->bec.txerr; + cf->data[7] = mc->pdev->bec.rxerr; + mc->pdev->dev.can.can_stats.error_passive++; break; case CAN_STATE_ERROR_WARNING: cf->can_id |= CAN_ERR_CRTL; - cf->data[1] |= CAN_ERR_CRTL_TX_WARNING | - CAN_ERR_CRTL_RX_WARNING; + cf->data[1] = (mc->pdev->bec.txerr > mc->pdev->bec.rxerr) ? + CAN_ERR_CRTL_TX_WARNING : + CAN_ERR_CRTL_RX_WARNING; + cf->data[6] = mc->pdev->bec.txerr; + cf->data[7] = mc->pdev->bec.rxerr; + mc->pdev->dev.can.can_stats.error_warning++; break; case CAN_STATE_ERROR_ACTIVE: cf->can_id |= CAN_ERR_CRTL; cf->data[1] = CAN_ERR_CRTL_ACTIVE; + + /* sync local copies of rxerr/txerr counters */ + mc->pdev->bec.txerr = 0; + mc->pdev->bec.rxerr = 0; break; default: /* CAN_STATE_MAX (trick to handle other errors) */ - cf->can_id |= CAN_ERR_CRTL; - cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW; - mc->netdev->stats.rx_over_errors++; - mc->netdev->stats.rx_errors++; + if (n & PCAN_USB_ERROR_TXQFULL) + netdev_dbg(mc->netdev, "device Tx queue full)\n"); + + if (n & PCAN_USB_ERROR_RXQOVR) { + netdev_dbg(mc->netdev, "data overrun interrupt\n"); + cf->can_id |= CAN_ERR_CRTL; + cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW; + mc->netdev->stats.rx_over_errors++; + mc->netdev->stats.rx_errors++; + } + + cf->data[6] = mc->pdev->bec.txerr; + cf->data[7] = mc->pdev->bec.rxerr; new_state = mc->pdev->dev.can.state; break; @@ -552,6 +602,30 @@ static int pcan_usb_decode_error(struct pcan_usb_msg_context *mc, u8 n, return 0; } +/* decode bus event usb packet: first byte contains rxerr while 2nd one contains + * txerr. + */ +static int pcan_usb_handle_bus_evt(struct pcan_usb_msg_context *mc, u8 ir) +{ + struct pcan_usb *pdev = mc->pdev; + + /* acccording to the content of the packet */ + switch (ir) { + case PCAN_USB_ERR_CNT: + + /* save rx/tx error counters from in the device context */ + pdev->bec.rxerr = mc->ptr[0]; + pdev->bec.txerr = mc->ptr[1]; + break; + + default: + /* reserved */ + break; + } + + return 0; +} + /* * decode non-data usb message */ @@ -606,9 +680,10 @@ static int pcan_usb_decode_status(struct pcan_usb_msg_context *mc, break; case PCAN_USB_REC_BUSEVT: - /* error frame/bus event */ - if (n & PCAN_USB_ERROR_TXQFULL) - netdev_dbg(mc->netdev, "device Tx queue full)\n"); + /* bus event notifications (get rxerr/txerr) */ + err = pcan_usb_handle_bus_evt(mc, n); + if (err) + return err; break; default: netdev_err(mc->netdev, "unexpected function %u\n", f); @@ -792,20 +867,44 @@ static int pcan_usb_encode_msg(struct peak_usb_device *dev, struct sk_buff *skb, return 0; } +/* socket callback used to copy berr counters values received through USB */ +static int pcan_usb_get_berr_counter(const struct net_device *netdev, + struct can_berr_counter *bec) +{ + struct peak_usb_device *dev = netdev_priv(netdev); + struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev); + + *bec = pdev->bec; + + /* must return 0 */ + return 0; +} + /* * start interface */ static int pcan_usb_start(struct peak_usb_device *dev) { struct pcan_usb *pdev = container_of(dev, struct pcan_usb, dev); + int err; /* number of bits used in timestamps read from adapter struct */ peak_usb_init_time_ref(&pdev->time_ref, &pcan_usb); + pdev->bec.rxerr = 0; + pdev->bec.txerr = 0; + + /* be notified on error counter changes (if requested by user) */ + if (dev->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING) { + err = pcan_usb_set_err_frame(dev, PCAN_USB_BERR_MASK); + if (err) + netdev_warn(dev->netdev, + "Asking for BERR reporting error %u\n", + err); + } + /* if revision greater than 3, can put silent mode on/off */ if (dev->device_rev > 3) { - int err; - err = pcan_usb_set_silent(dev, dev->can.ctrlmode & CAN_CTRLMODE_LISTENONLY); if (err) @@ -892,7 +991,8 @@ const struct peak_usb_adapter pcan_usb = { .name = "PCAN-USB", .device_id = PCAN_USB_PRODUCT_ID, .ctrl_count = 1, - .ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY, + .ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES | CAN_CTRLMODE_LISTENONLY | + CAN_CTRLMODE_BERR_REPORTING, .clock = { .freq = PCAN_USB_CRYSTAL_HZ / 2 , }, @@ -925,4 +1025,5 @@ const struct peak_usb_adapter pcan_usb = { .dev_encode_msg = pcan_usb_encode_msg, .dev_start = pcan_usb_start, .dev_restart_async = pcan_usb_restart_async, + .do_get_berr_counter = pcan_usb_get_berr_counter, }; -- 2.11.0