#include "can/lpc17xx_can.h"
static void CAN_configPin();
-static void CAN_setBusTiming(struct canchip_t *chip);
-
-#define MAX_TRANSMIT_WAIT_LOOPS 20
-
-/*
- * CAN harware-dependent bit-timing constant
- *
- * Used for calculating and checking bit-timing parameters
- */
-
-struct can_bittiming_const {
- char name[16]; /* Name of the CAN controller hardware */
- uint32_t tseg1_min; /* Time segement 1 = prop_seg + phase_seg1 */
- uint32_t tseg1_max;
- uint32_t tseg2_min; /* Time segement 2 = phase_seg2 */
- uint32_t tseg2_max;
- uint32_t sjw_max; /* Synchronisation jump width */
- uint32_t brp_min; /* Bit-rate prescaler */
- uint32_t brp_max;
- uint32_t brp_inc;
-};
-
-static struct can_bittiming_const lpc17xx_can_bittiming_const = {
- .name = "lpc17xx_can",
- .tseg1_min = 1,
- .tseg1_max = 16,
- .tseg2_min = 1,
- .tseg2_max = 8,
- .sjw_max = 4,
- .brp_min = 1,
- .brp_max = 1024,
- .brp_inc = 1,
-};
-
-//---------------------------------------------------------------------------------
-//---------------------------------------------------------------------------------
// board can-lmc1 specific functions:
int can_lmc1_init_chip_data(struct candevice_t *candev, int chipnr){
+ struct can_lmc1_chip_data *chip_data;
+
// used CAN1 peripherial -> CAN1 registers base
candev->chip[chipnr]->chip_base_addr = CAN1_REGS_BASE;
+ // clock for CAN
candev->chip[chipnr]->clock = system_frequency / 4;
lpc17xx_fill_chipspecops(candev->chip[chipnr]);
if (candev->chip[chipnr]->chip_data==NULL)
return -ENOMEM;
+
+ chip_data = (struct can_lmc1_chip_data*) candev->chip[chipnr]->chip_data;
+ chip_data->flags = 0;
+
return 0;
}
int best_tseg=0, best_brp=0, best_rate=0, brp=0;
int tseg=0, tseg1=0, tseg2=0;
- struct can_bittiming_const *btc = &lpc17xx_can_bittiming_const;
+ struct can_bittiming_const btc_buff;
+ struct can_bittiming_const *btc = &btc_buff;
- // right ?
- //clock /=2;
+ chip->chipspecops->get_bittiming_const(chip, btc);
/* tseg even = round down, odd = round up */
for (tseg=(0+0+2)*2; tseg<=(btc->tseg2_max+btc->tseg1_max+2)*2+1; tseg++) {
(100*(best_tseg-tseg2)/(best_tseg+1)));
- CAN_set_bittiming(chip, best_brp, sjw, tseg1, tseg2);
-
+ if(chip->chipspecops->set_bittiming(chip, ++best_brp, ++sjw, ++tseg1, ++tseg2) < 0)
+ return -EINVAL;
return 0;
}
if (!chip->baudrate)
chip->baudrate=1000000;
- printf("CAN CHIP INIT, baudrate: %d\n", (int) chip->baudrate);
-
if (lpc17xx_baud_rate(chip,chip->baudrate,chip->clock,0,75,0))
return -ENODEV;
int lpc17xx_pre_write_config(struct canchip_t *chip, struct msgobj_t *obj,
struct canmsg_t *msg)
{
+ uint32_t i=0;
+ // check status of TB1
+ while (!(can_read_reg(chip, CAN_SR_o) & CAN_SR_TBS1)){
+ if(i++<MAX_TRANSMIT_WAIT_LOOPS)
+ continue;
+
+ // request command to abort transmission request
+ can_write_reg(chip, CAN_CMR_AT, CAN_CMR_o);
+ return 0;
+ }
+
CAN_send(chip, msg);
return 0;
if(i++<MAX_TRANSMIT_WAIT_LOOPS)
continue;
+ CANMSG("Abort transmission request\n");
+
// request command to abort transmission request
can_write_reg(chip, CAN_CMR_AT, CAN_CMR_o);
break;
uint32_t i;
struct msgobj_t *obj;
obj = chip->msgobj[0];
-
i = can_read_reg(chip, CAN_ICR_o);
}
+int lpc17xx_set_bittiming(struct canchip_t *chip, int brp, int sjw, int tseg1, int tseg2){
+
+ uint8_t SAM = 0; // 0 = the bus is sampled once
+
+ if((--brp)<0)
+ return -EINVAL;
+
+ if((--sjw)<0)
+ return -EINVAL;
+
+ if((--tseg1)<0)
+ return -EINVAL;
+
+ if((--tseg2)<0)
+ return -EINVAL;
+
+
+ //debug print
+ CANMSG("BRP: %d, SJW: %d, TSEG1: %d, TSEG2: %d \n", brp+1, sjw+1, tseg1+1, tseg2+1);
+
+ can_disable_irq(chip->chip_irq);
+
+ // enter reset mode
+ can_write_reg(chip, 1, CAN_MOD_o);
+
+ // set bittiming register
+ can_write_reg(chip, ((SAM<<23)|(tseg2<<20)|(tseg1<<16)|(sjw<<14)|(brp<<0)), CAN_BTR_o);
+
+ // return to normal operating
+ can_write_reg(chip, 0, CAN_MOD_o);
+
+ can_enable_irq(chip->chip_irq);
+
+ return 0;
+}
+
+int lpc17xx_get_bittiming_const(struct canchip_t *chip, struct can_bittiming_const *btc) {
+ btc->tseg1_min = 1;
+ btc->tseg1_max = 16;
+ btc->tseg2_min = 1;
+ btc->tseg2_max = 8;
+ btc->sjw_max = 4;
+ btc->brp_min = 1;
+ btc->brp_max = 1024;
+ btc->brp_inc = 1;
+
+ return 0;
+}
+
+
int lpc17xx_fill_chipspecops(struct canchip_t *chip){
chip->max_objects=1;
chipspecops->wakeup_tx = lpc17xx_wakeup_tx;
chipspecops->irq_handler = lpc17xx_irq_handler;
+ chipspecops->set_bittiming = lpc17xx_set_bittiming;
+ chipspecops->get_bittiming_const = lpc17xx_get_bittiming_const;
+
return 0;
}
volatile uint32_t can_tfi1;
uint32_t i=0;
- // check status of TB1
- while (!(can_read_reg(chip, CAN_SR_o) & CAN_SR_TBS1)){
- if(i++<MAX_TRANSMIT_WAIT_LOOPS)
- continue;
-
- // request command to abort transmission request
- can_write_reg(chip, CAN_CMR_AT, CAN_CMR_o);
- return;
- }
-
can_tfi1 = can_read_reg(chip, CAN_TFI1_o);
can_tfi1 &= ~0x000F0000;
}
-void CAN_set_bittiming(struct canchip_t *chip, uint32_t brp, uint32_t sjw, uint32_t tseg1, uint32_t tseg2){
-
- uint8_t SAM = 0; // 0 = the bus is sampled once
-
- //debug print
- printf("BRP: %d, SJW: %d, TSEG1: %d, TSEG2: %d \n", brp+1, sjw+1, tseg1+1, tseg2+1);
-
- can_disable_irq(chip->chip_irq);
- // enter reset mode
- can_write_reg(chip, 1, CAN_MOD_o);
-
-
- can_write_reg(chip, ((SAM<<23)|(tseg2<<20)|(tseg1<<16)|(sjw<<14)|(brp<<0)), CAN_BTR_o);
-
-
- // return to normal operating
- can_write_reg(chip, 0, CAN_MOD_o);
-
- can_enable_irq(chip->chip_irq);
-}
-
-
void CAN_init(struct canchip_t *chip){
uint32_t tmp;