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can: xilinx_can: fix RX loop if RXNEMP is asserted without RXOK
[linux-block.git] / drivers / net / can / xilinx_can.c
CommitLineData
b1201e44
KA		 1/* Xilinx CAN device driver
2 *
3 * Copyright (C) 2012 - 2014 Xilinx, Inc.
4 * Copyright (C) 2009 PetaLogix. All rights reserved.
5 *
6 * Description:
7 * This driver is developed for Axi CAN IP and for Zynq CANPS Controller.
8 * This program is free software: you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation, either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 */
18
19#include <linux/clk.h>
20#include <linux/errno.h>
21#include <linux/init.h>
22#include <linux/interrupt.h>
23#include <linux/io.h>
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/netdevice.h>
27#include <linux/of.h>
28#include <linux/platform_device.h>
29#include <linux/skbuff.h>
30#include <linux/string.h>
31#include <linux/types.h>
32#include <linux/can/dev.h>
33#include <linux/can/error.h>
34#include <linux/can/led.h>
4716620d 35#include <linux/pm_runtime.h>
b1201e44
KA		 36
37#define DRIVER_NAME "xilinx_can"
38
39/* CAN registers set */
40enum xcan_reg {
41 XCAN_SRR_OFFSET = 0x00, /* Software reset */
42 XCAN_MSR_OFFSET = 0x04, /* Mode select */
43 XCAN_BRPR_OFFSET = 0x08, /* Baud rate prescaler */
44 XCAN_BTR_OFFSET = 0x0C, /* Bit timing */
45 XCAN_ECR_OFFSET = 0x10, /* Error counter */
46 XCAN_ESR_OFFSET = 0x14, /* Error status */
47 XCAN_SR_OFFSET = 0x18, /* Status */
48 XCAN_ISR_OFFSET = 0x1C, /* Interrupt status */
49 XCAN_IER_OFFSET = 0x20, /* Interrupt enable */
50 XCAN_ICR_OFFSET = 0x24, /* Interrupt clear */
51 XCAN_TXFIFO_ID_OFFSET = 0x30,/* TX FIFO ID */
52 XCAN_TXFIFO_DLC_OFFSET = 0x34, /* TX FIFO DLC */
53 XCAN_TXFIFO_DW1_OFFSET = 0x38, /* TX FIFO Data Word 1 */
54 XCAN_TXFIFO_DW2_OFFSET = 0x3C, /* TX FIFO Data Word 2 */
55 XCAN_RXFIFO_ID_OFFSET = 0x50, /* RX FIFO ID */
56 XCAN_RXFIFO_DLC_OFFSET = 0x54, /* RX FIFO DLC */
57 XCAN_RXFIFO_DW1_OFFSET = 0x58, /* RX FIFO Data Word 1 */
58 XCAN_RXFIFO_DW2_OFFSET = 0x5C, /* RX FIFO Data Word 2 */
59};
60
61/* CAN register bit masks - XCAN_<REG>_<BIT>_MASK */
62#define XCAN_SRR_CEN_MASK 0x00000002 /* CAN enable */
63#define XCAN_SRR_RESET_MASK 0x00000001 /* Soft Reset the CAN core */
64#define XCAN_MSR_LBACK_MASK 0x00000002 /* Loop back mode select */
65#define XCAN_MSR_SLEEP_MASK 0x00000001 /* Sleep mode select */
66#define XCAN_BRPR_BRP_MASK 0x000000FF /* Baud rate prescaler */
67#define XCAN_BTR_SJW_MASK 0x00000180 /* Synchronous jump width */
68#define XCAN_BTR_TS2_MASK 0x00000070 /* Time segment 2 */
69#define XCAN_BTR_TS1_MASK 0x0000000F /* Time segment 1 */
70#define XCAN_ECR_REC_MASK 0x0000FF00 /* Receive error counter */
71#define XCAN_ECR_TEC_MASK 0x000000FF /* Transmit error counter */
72#define XCAN_ESR_ACKER_MASK 0x00000010 /* ACK error */
73#define XCAN_ESR_BERR_MASK 0x00000008 /* Bit error */
74#define XCAN_ESR_STER_MASK 0x00000004 /* Stuff error */
75#define XCAN_ESR_FMER_MASK 0x00000002 /* Form error */
76#define XCAN_ESR_CRCER_MASK 0x00000001 /* CRC error */
77#define XCAN_SR_TXFLL_MASK 0x00000400 /* TX FIFO is full */
78#define XCAN_SR_ESTAT_MASK 0x00000180 /* Error status */
79#define XCAN_SR_ERRWRN_MASK 0x00000040 /* Error warning */
80#define XCAN_SR_NORMAL_MASK 0x00000008 /* Normal mode */
81#define XCAN_SR_LBACK_MASK 0x00000002 /* Loop back mode */
82#define XCAN_SR_CONFIG_MASK 0x00000001 /* Configuration mode */
83#define XCAN_IXR_TXFEMP_MASK 0x00004000 /* TX FIFO Empty */
84#define XCAN_IXR_WKUP_MASK 0x00000800 /* Wake up interrupt */
85#define XCAN_IXR_SLP_MASK 0x00000400 /* Sleep interrupt */
86#define XCAN_IXR_BSOFF_MASK 0x00000200 /* Bus off interrupt */
87#define XCAN_IXR_ERROR_MASK 0x00000100 /* Error interrupt */
88#define XCAN_IXR_RXNEMP_MASK 0x00000080 /* RX FIFO NotEmpty intr */
89#define XCAN_IXR_RXOFLW_MASK 0x00000040 /* RX FIFO Overflow intr */
90#define XCAN_IXR_RXOK_MASK 0x00000010 /* Message received intr */
91#define XCAN_IXR_TXFLL_MASK 0x00000004 /* Tx FIFO Full intr */
92#define XCAN_IXR_TXOK_MASK 0x00000002 /* TX successful intr */
93#define XCAN_IXR_ARBLST_MASK 0x00000001 /* Arbitration lost intr */
94#define XCAN_IDR_ID1_MASK 0xFFE00000 /* Standard msg identifier */
95#define XCAN_IDR_SRR_MASK 0x00100000 /* Substitute remote TXreq */
96#define XCAN_IDR_IDE_MASK 0x00080000 /* Identifier extension */
97#define XCAN_IDR_ID2_MASK 0x0007FFFE /* Extended message ident */
98#define XCAN_IDR_RTR_MASK 0x00000001 /* Remote TX request */
99#define XCAN_DLCR_DLC_MASK 0xF0000000 /* Data length code */
100
101#define XCAN_INTR_ALL (XCAN_IXR_TXOK_MASK | XCAN_IXR_BSOFF_MASK |\
102 XCAN_IXR_WKUP_MASK | XCAN_IXR_SLP_MASK | \
103 XCAN_IXR_RXNEMP_MASK | XCAN_IXR_ERROR_MASK | \
32852c56 104 XCAN_IXR_ARBLST_MASK)
b1201e44
KA		 105
106/* CAN register bit shift - XCAN_<REG>_<BIT>_SHIFT */
107#define XCAN_BTR_SJW_SHIFT 7 /* Synchronous jump width */
108#define XCAN_BTR_TS2_SHIFT 4 /* Time segment 2 */
109#define XCAN_IDR_ID1_SHIFT 21 /* Standard Messg Identifier */
110#define XCAN_IDR_ID2_SHIFT 1 /* Extended Message Identifier */
111#define XCAN_DLCR_DLC_SHIFT 28 /* Data length code */
112#define XCAN_ESR_REC_SHIFT 8 /* Rx Error Count */
113
114/* CAN frame length constants */
115#define XCAN_FRAME_MAX_DATA_LEN 8
116#define XCAN_TIMEOUT (1 * HZ)
117
118/**
119 * struct xcan_priv - This definition define CAN driver instance
120 * @can: CAN private data structure.
121 * @tx_head: Tx CAN packets ready to send on the queue
122 * @tx_tail: Tx CAN packets successfully sended on the queue
123 * @tx_max: Maximum number packets the driver can send
124 * @napi: NAPI structure
125 * @read_reg: For reading data from CAN registers
126 * @write_reg: For writing data to CAN registers
127 * @dev: Network device data structure
128 * @reg_base: Ioremapped address to registers
129 * @irq_flags: For request_irq()
130 * @bus_clk: Pointer to struct clk
131 * @can_clk: Pointer to struct clk
132 */
133struct xcan_priv {
134 struct can_priv can;
135 unsigned int tx_head;
136 unsigned int tx_tail;
137 unsigned int tx_max;
138 struct napi_struct napi;
139 u32 (*read_reg)(const struct xcan_priv *priv, enum xcan_reg reg);
140 void (*write_reg)(const struct xcan_priv *priv, enum xcan_reg reg,
141 u32 val);
4716620d 142 struct device *dev;
b1201e44
KA		 143 void __iomem *reg_base;
144 unsigned long irq_flags;
145 struct clk *bus_clk;
146 struct clk *can_clk;
147};
148
149/* CAN Bittiming constants as per Xilinx CAN specs */
150static const struct can_bittiming_const xcan_bittiming_const = {
151 .name = DRIVER_NAME,
152 .tseg1_min = 1,
153 .tseg1_max = 16,
154 .tseg2_min = 1,
155 .tseg2_max = 8,
156 .sjw_max = 4,
157 .brp_min = 1,
158 .brp_max = 256,
159 .brp_inc = 1,
160};
161
162/**
163 * xcan_write_reg_le - Write a value to the device register little endian
164 * @priv: Driver private data structure
165 * @reg: Register offset
166 * @val: Value to write at the Register offset
167 *
168 * Write data to the paricular CAN register
169 */
170static void xcan_write_reg_le(const struct xcan_priv *priv, enum xcan_reg reg,
171 u32 val)
172{
173 iowrite32(val, priv->reg_base + reg);
174}
175
176/**
177 * xcan_read_reg_le - Read a value from the device register little endian
178 * @priv: Driver private data structure
179 * @reg: Register offset
180 *
181 * Read data from the particular CAN register
182 * Return: value read from the CAN register
183 */
184static u32 xcan_read_reg_le(const struct xcan_priv *priv, enum xcan_reg reg)
185{
186 return ioread32(priv->reg_base + reg);
187}
188
189/**
190 * xcan_write_reg_be - Write a value to the device register big endian
191 * @priv: Driver private data structure
192 * @reg: Register offset
193 * @val: Value to write at the Register offset
194 *
195 * Write data to the paricular CAN register
196 */
197static void xcan_write_reg_be(const struct xcan_priv *priv, enum xcan_reg reg,
198 u32 val)
199{
200 iowrite32be(val, priv->reg_base + reg);
201}
202
203/**
204 * xcan_read_reg_be - Read a value from the device register big endian
205 * @priv: Driver private data structure
206 * @reg: Register offset
207 *
208 * Read data from the particular CAN register
209 * Return: value read from the CAN register
210 */
211static u32 xcan_read_reg_be(const struct xcan_priv *priv, enum xcan_reg reg)
212{
213 return ioread32be(priv->reg_base + reg);
214}
215
216/**
217 * set_reset_mode - Resets the CAN device mode
218 * @ndev: Pointer to net_device structure
219 *
220 * This is the driver reset mode routine.The driver
221 * enters into configuration mode.
222 *
223 * Return: 0 on success and failure value on error
224 */
225static int set_reset_mode(struct net_device *ndev)
226{
227 struct xcan_priv *priv = netdev_priv(ndev);
228 unsigned long timeout;
229
230 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
231
232 timeout = jiffies + XCAN_TIMEOUT;
233 while (!(priv->read_reg(priv, XCAN_SR_OFFSET) & XCAN_SR_CONFIG_MASK)) {
234 if (time_after(jiffies, timeout)) {
235 netdev_warn(ndev, "timed out for config mode\n");
236 return -ETIMEDOUT;
237 }
238 usleep_range(500, 10000);
239 }
240
241 return 0;
242}
243
244/**
245 * xcan_set_bittiming - CAN set bit timing routine
246 * @ndev: Pointer to net_device structure
247 *
248 * This is the driver set bittiming routine.
249 * Return: 0 on success and failure value on error
250 */
251static int xcan_set_bittiming(struct net_device *ndev)
252{
253 struct xcan_priv *priv = netdev_priv(ndev);
254 struct can_bittiming *bt = &priv->can.bittiming;
255 u32 btr0, btr1;
256 u32 is_config_mode;
257
258 /* Check whether Xilinx CAN is in configuration mode.
259 * It cannot set bit timing if Xilinx CAN is not in configuration mode.
260 */
261 is_config_mode = priv->read_reg(priv, XCAN_SR_OFFSET) &
262 XCAN_SR_CONFIG_MASK;
263 if (!is_config_mode) {
264 netdev_alert(ndev,
265 "BUG! Cannot set bittiming - CAN is not in config mode\n");
266 return -EPERM;
267 }
268
269 /* Setting Baud Rate prescalar value in BRPR Register */
270 btr0 = (bt->brp - 1);
271
272 /* Setting Time Segment 1 in BTR Register */
273 btr1 = (bt->prop_seg + bt->phase_seg1 - 1);
274
275 /* Setting Time Segment 2 in BTR Register */
276 btr1 |= (bt->phase_seg2 - 1) << XCAN_BTR_TS2_SHIFT;
277
278 /* Setting Synchronous jump width in BTR Register */
279 btr1 |= (bt->sjw - 1) << XCAN_BTR_SJW_SHIFT;
280
281 priv->write_reg(priv, XCAN_BRPR_OFFSET, btr0);
282 priv->write_reg(priv, XCAN_BTR_OFFSET, btr1);
283
284 netdev_dbg(ndev, "BRPR=0x%08x, BTR=0x%08x\n",
285 priv->read_reg(priv, XCAN_BRPR_OFFSET),
286 priv->read_reg(priv, XCAN_BTR_OFFSET));
287
288 return 0;
289}
290
291/**
292 * xcan_chip_start - This the drivers start routine
293 * @ndev: Pointer to net_device structure
294 *
295 * This is the drivers start routine.
296 * Based on the State of the CAN device it puts
297 * the CAN device into a proper mode.
298 *
299 * Return: 0 on success and failure value on error
300 */
301static int xcan_chip_start(struct net_device *ndev)
302{
303 struct xcan_priv *priv = netdev_priv(ndev);
fb3ec7ba
SM		 304 u32 reg_msr, reg_sr_mask;
305 int err;
b1201e44
KA		 306 unsigned long timeout;
307
308 /* Check if it is in reset mode */
309 err = set_reset_mode(ndev);
310 if (err < 0)
311 return err;
312
313 err = xcan_set_bittiming(ndev);
314 if (err < 0)
315 return err;
316
317 /* Enable interrupts */
318 priv->write_reg(priv, XCAN_IER_OFFSET, XCAN_INTR_ALL);
319
320 /* Check whether it is loopback mode or normal mode */
321 if (priv->can.ctrlmode & CAN_CTRLMODE_LOOPBACK) {
322 reg_msr = XCAN_MSR_LBACK_MASK;
323 reg_sr_mask = XCAN_SR_LBACK_MASK;
324 } else {
325 reg_msr = 0x0;
326 reg_sr_mask = XCAN_SR_NORMAL_MASK;
327 }
328
329 priv->write_reg(priv, XCAN_MSR_OFFSET, reg_msr);
330 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_CEN_MASK);
331
332 timeout = jiffies + XCAN_TIMEOUT;
333 while (!(priv->read_reg(priv, XCAN_SR_OFFSET) & reg_sr_mask)) {
334 if (time_after(jiffies, timeout)) {
335 netdev_warn(ndev,
336 "timed out for correct mode\n");
337 return -ETIMEDOUT;
338 }
339 }
340 netdev_dbg(ndev, "status:#x%08x\n",
341 priv->read_reg(priv, XCAN_SR_OFFSET));
342
343 priv->can.state = CAN_STATE_ERROR_ACTIVE;
344 return 0;
345}
346
347/**
348 * xcan_do_set_mode - This sets the mode of the driver
349 * @ndev: Pointer to net_device structure
350 * @mode: Tells the mode of the driver
351 *
352 * This check the drivers state and calls the
353 * the corresponding modes to set.
354 *
355 * Return: 0 on success and failure value on error
356 */
357static int xcan_do_set_mode(struct net_device *ndev, enum can_mode mode)
358{
359 int ret;
360
361 switch (mode) {
362 case CAN_MODE_START:
363 ret = xcan_chip_start(ndev);
364 if (ret < 0) {
365 netdev_err(ndev, "xcan_chip_start failed!\n");
366 return ret;
367 }
368 netif_wake_queue(ndev);
369 break;
370 default:
371 ret = -EOPNOTSUPP;
372 break;
373 }
374
375 return ret;
376}
377
378/**
379 * xcan_start_xmit - Starts the transmission
380 * @skb: sk_buff pointer that contains data to be Txed
381 * @ndev: Pointer to net_device structure
382 *
383 * This function is invoked from upper layers to initiate transmission. This
384 * function uses the next available free txbuff and populates their fields to
385 * start the transmission.
386 *
387 * Return: 0 on success and failure value on error
388 */
389static int xcan_start_xmit(struct sk_buff *skb, struct net_device *ndev)
390{
391 struct xcan_priv *priv = netdev_priv(ndev);
392 struct net_device_stats *stats = &ndev->stats;
393 struct can_frame *cf = (struct can_frame *)skb->data;
394 u32 id, dlc, data[2] = {0, 0};
395
396 if (can_dropped_invalid_skb(ndev, skb))
397 return NETDEV_TX_OK;
398
399 /* Check if the TX buffer is full */
400 if (unlikely(priv->read_reg(priv, XCAN_SR_OFFSET) &
401 XCAN_SR_TXFLL_MASK)) {
402 netif_stop_queue(ndev);
403 netdev_err(ndev, "BUG!, TX FIFO full when queue awake!\n");
404 return NETDEV_TX_BUSY;
405 }
406
407 /* Watch carefully on the bit sequence */
408 if (cf->can_id & CAN_EFF_FLAG) {
409 /* Extended CAN ID format */
410 id = ((cf->can_id & CAN_EFF_MASK) << XCAN_IDR_ID2_SHIFT) &
411 XCAN_IDR_ID2_MASK;
412 id |= (((cf->can_id & CAN_EFF_MASK) >>
413 (CAN_EFF_ID_BITS-CAN_SFF_ID_BITS)) <<
414 XCAN_IDR_ID1_SHIFT) & XCAN_IDR_ID1_MASK;
415
416 /* The substibute remote TX request bit should be "1"
417 * for extended frames as in the Xilinx CAN datasheet
418 */
419 id |= XCAN_IDR_IDE_MASK | XCAN_IDR_SRR_MASK;
420
421 if (cf->can_id & CAN_RTR_FLAG)
422 /* Extended frames remote TX request */
423 id |= XCAN_IDR_RTR_MASK;
424 } else {
425 /* Standard CAN ID format */
426 id = ((cf->can_id & CAN_SFF_MASK) << XCAN_IDR_ID1_SHIFT) &
427 XCAN_IDR_ID1_MASK;
428
429 if (cf->can_id & CAN_RTR_FLAG)
430 /* Standard frames remote TX request */
431 id |= XCAN_IDR_SRR_MASK;
432 }
433
434 dlc = cf->can_dlc << XCAN_DLCR_DLC_SHIFT;
435
436 if (cf->can_dlc > 0)
437 data[0] = be32_to_cpup((__be32 *)(cf->data + 0));
438 if (cf->can_dlc > 4)
439 data[1] = be32_to_cpup((__be32 *)(cf->data + 4));
440
441 can_put_echo_skb(skb, ndev, priv->tx_head % priv->tx_max);
442 priv->tx_head++;
443
444 /* Write the Frame to Xilinx CAN TX FIFO */
445 priv->write_reg(priv, XCAN_TXFIFO_ID_OFFSET, id);
446 /* If the CAN frame is RTR frame this write triggers tranmission */
447 priv->write_reg(priv, XCAN_TXFIFO_DLC_OFFSET, dlc);
448 if (!(cf->can_id & CAN_RTR_FLAG)) {
449 priv->write_reg(priv, XCAN_TXFIFO_DW1_OFFSET, data[0]);
450 /* If the CAN frame is Standard/Extended frame this
451 * write triggers tranmission
452 */
453 priv->write_reg(priv, XCAN_TXFIFO_DW2_OFFSET, data[1]);
454 stats->tx_bytes += cf->can_dlc;
455 }
456
457 /* Check if the TX buffer is full */
458 if ((priv->tx_head - priv->tx_tail) == priv->tx_max)
459 netif_stop_queue(ndev);
460
461 return NETDEV_TX_OK;
462}
463
464/**
465 * xcan_rx - Is called from CAN isr to complete the received
466 * frame processing
467 * @ndev: Pointer to net_device structure
468 *
469 * This function is invoked from the CAN isr(poll) to process the Rx frames. It
470 * does minimal processing and invokes "netif_receive_skb" to complete further
471 * processing.
472 * Return: 1 on success and 0 on failure.
473 */
474static int xcan_rx(struct net_device *ndev)
475{
476 struct xcan_priv *priv = netdev_priv(ndev);
477 struct net_device_stats *stats = &ndev->stats;
478 struct can_frame *cf;
479 struct sk_buff *skb;
480 u32 id_xcan, dlc, data[2] = {0, 0};
481
482 skb = alloc_can_skb(ndev, &cf);
483 if (unlikely(!skb)) {
484 stats->rx_dropped++;
485 return 0;
486 }
487
488 /* Read a frame from Xilinx zynq CANPS */
489 id_xcan = priv->read_reg(priv, XCAN_RXFIFO_ID_OFFSET);
490 dlc = priv->read_reg(priv, XCAN_RXFIFO_DLC_OFFSET) >>
491 XCAN_DLCR_DLC_SHIFT;
492
493 /* Change Xilinx CAN data length format to socketCAN data format */
494 cf->can_dlc = get_can_dlc(dlc);
495
496 /* Change Xilinx CAN ID format to socketCAN ID format */
497 if (id_xcan & XCAN_IDR_IDE_MASK) {
498 /* The received frame is an Extended format frame */
499 cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >> 3;
500 cf->can_id |= (id_xcan & XCAN_IDR_ID2_MASK) >>
501 XCAN_IDR_ID2_SHIFT;
502 cf->can_id |= CAN_EFF_FLAG;
503 if (id_xcan & XCAN_IDR_RTR_MASK)
504 cf->can_id |= CAN_RTR_FLAG;
505 } else {
506 /* The received frame is a standard format frame */
507 cf->can_id = (id_xcan & XCAN_IDR_ID1_MASK) >>
508 XCAN_IDR_ID1_SHIFT;
509 if (id_xcan & XCAN_IDR_SRR_MASK)
510 cf->can_id |= CAN_RTR_FLAG;
511 }
512
5793affe
JLP		 513 /* DW1/DW2 must always be read to remove message from RXFIFO */
514 data[0] = priv->read_reg(priv, XCAN_RXFIFO_DW1_OFFSET);
515 data[1] = priv->read_reg(priv, XCAN_RXFIFO_DW2_OFFSET);
b1201e44 516
5793affe 517 if (!(cf->can_id & CAN_RTR_FLAG)) {
b1201e44
KA		 518 /* Change Xilinx CAN data format to socketCAN data format */
519 if (cf->can_dlc > 0)
520 *(__be32 *)(cf->data) = cpu_to_be32(data[0]);
521 if (cf->can_dlc > 4)
522 *(__be32 *)(cf->data + 4) = cpu_to_be32(data[1]);
523 }
524
525 stats->rx_bytes += cf->can_dlc;
526 stats->rx_packets++;
527 netif_receive_skb(skb);
528
529 return 1;
530}
531
532/**
533 * xcan_err_interrupt - error frame Isr
534 * @ndev: net_device pointer
535 * @isr: interrupt status register value
536 *
537 * This is the CAN error interrupt and it will
538 * check the the type of error and forward the error
539 * frame to upper layers.
540 */
541static void xcan_err_interrupt(struct net_device *ndev, u32 isr)
542{
543 struct xcan_priv *priv = netdev_priv(ndev);
544 struct net_device_stats *stats = &ndev->stats;
545 struct can_frame *cf;
546 struct sk_buff *skb;
547 u32 err_status, status, txerr = 0, rxerr = 0;
548
549 skb = alloc_can_err_skb(ndev, &cf);
550
551 err_status = priv->read_reg(priv, XCAN_ESR_OFFSET);
552 priv->write_reg(priv, XCAN_ESR_OFFSET, err_status);
553 txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK;
554 rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) &
555 XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT);
556 status = priv->read_reg(priv, XCAN_SR_OFFSET);
557
558 if (isr & XCAN_IXR_BSOFF_MASK) {
559 priv->can.state = CAN_STATE_BUS_OFF;
560 priv->can.can_stats.bus_off++;
561 /* Leave device in Config Mode in bus-off state */
562 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
563 can_bus_off(ndev);
564 if (skb)
565 cf->can_id |= CAN_ERR_BUSOFF;
566 } else if ((status & XCAN_SR_ESTAT_MASK) == XCAN_SR_ESTAT_MASK) {
567 priv->can.state = CAN_STATE_ERROR_PASSIVE;
568 priv->can.can_stats.error_passive++;
569 if (skb) {
570 cf->can_id |= CAN_ERR_CRTL;
571 cf->data[1] = (rxerr > 127) ?
572 CAN_ERR_CRTL_RX_PASSIVE :
573 CAN_ERR_CRTL_TX_PASSIVE;
574 cf->data[6] = txerr;
575 cf->data[7] = rxerr;
576 }
577 } else if (status & XCAN_SR_ERRWRN_MASK) {
578 priv->can.state = CAN_STATE_ERROR_WARNING;
579 priv->can.can_stats.error_warning++;
580 if (skb) {
581 cf->can_id |= CAN_ERR_CRTL;
582 cf->data[1] |= (txerr > rxerr) ?
583 CAN_ERR_CRTL_TX_WARNING :
584 CAN_ERR_CRTL_RX_WARNING;
585 cf->data[6] = txerr;
586 cf->data[7] = rxerr;
587 }
588 }
589
590 /* Check for Arbitration lost interrupt */
591 if (isr & XCAN_IXR_ARBLST_MASK) {
592 priv->can.can_stats.arbitration_lost++;
593 if (skb) {
594 cf->can_id |= CAN_ERR_LOSTARB;
595 cf->data[0] = CAN_ERR_LOSTARB_UNSPEC;
596 }
597 }
598
599 /* Check for RX FIFO Overflow interrupt */
600 if (isr & XCAN_IXR_RXOFLW_MASK) {
601 stats->rx_over_errors++;
602 stats->rx_errors++;
b1201e44
KA		 603 if (skb) {
604 cf->can_id |= CAN_ERR_CRTL;
605 cf->data[1] |= CAN_ERR_CRTL_RX_OVERFLOW;
606 }
607 }
608
609 /* Check for error interrupt */
610 if (isr & XCAN_IXR_ERROR_MASK) {
a2ec19f8 611 if (skb)
b1201e44 612 cf->can_id |= CAN_ERR_PROT | CAN_ERR_BUSERROR;
b1201e44
KA		 613
614 /* Check for Ack error interrupt */
615 if (err_status & XCAN_ESR_ACKER_MASK) {
616 stats->tx_errors++;
617 if (skb) {
618 cf->can_id |= CAN_ERR_ACK;
ffd461f8 619 cf->data[3] = CAN_ERR_PROT_LOC_ACK;
b1201e44
KA		 620 }
621 }
622
623 /* Check for Bit error interrupt */
624 if (err_status & XCAN_ESR_BERR_MASK) {
625 stats->tx_errors++;
626 if (skb) {
627 cf->can_id |= CAN_ERR_PROT;
628 cf->data[2] = CAN_ERR_PROT_BIT;
629 }
630 }
631
632 /* Check for Stuff error interrupt */
633 if (err_status & XCAN_ESR_STER_MASK) {
634 stats->rx_errors++;
635 if (skb) {
636 cf->can_id |= CAN_ERR_PROT;
637 cf->data[2] = CAN_ERR_PROT_STUFF;
638 }
639 }
640
641 /* Check for Form error interrupt */
642 if (err_status & XCAN_ESR_FMER_MASK) {
643 stats->rx_errors++;
644 if (skb) {
645 cf->can_id |= CAN_ERR_PROT;
646 cf->data[2] = CAN_ERR_PROT_FORM;
647 }
648 }
649
650 /* Check for CRC error interrupt */
651 if (err_status & XCAN_ESR_CRCER_MASK) {
652 stats->rx_errors++;
653 if (skb) {
654 cf->can_id |= CAN_ERR_PROT;
ffd461f8 655 cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
b1201e44
KA		 656 }
657 }
658 priv->can.can_stats.bus_error++;
659 }
660
661 if (skb) {
662 stats->rx_packets++;
663 stats->rx_bytes += cf->can_dlc;
664 netif_rx(skb);
665 }
666
667 netdev_dbg(ndev, "%s: error status register:0x%x\n",
668 __func__, priv->read_reg(priv, XCAN_ESR_OFFSET));
669}
670
671/**
672 * xcan_state_interrupt - It will check the state of the CAN device
673 * @ndev: net_device pointer
674 * @isr: interrupt status register value
675 *
676 * This will checks the state of the CAN device
677 * and puts the device into appropriate state.
678 */
679static void xcan_state_interrupt(struct net_device *ndev, u32 isr)
680{
681 struct xcan_priv *priv = netdev_priv(ndev);
682
683 /* Check for Sleep interrupt if set put CAN device in sleep state */
684 if (isr & XCAN_IXR_SLP_MASK)
685 priv->can.state = CAN_STATE_SLEEPING;
686
687 /* Check for Wake up interrupt if set put CAN device in Active state */
688 if (isr & XCAN_IXR_WKUP_MASK)
689 priv->can.state = CAN_STATE_ERROR_ACTIVE;
690}
691
692/**
693 * xcan_rx_poll - Poll routine for rx packets (NAPI)
694 * @napi: napi structure pointer
695 * @quota: Max number of rx packets to be processed.
696 *
697 * This is the poll routine for rx part.
698 * It will process the packets maximux quota value.
699 *
700 * Return: number of packets received
701 */
702static int xcan_rx_poll(struct napi_struct *napi, int quota)
703{
704 struct net_device *ndev = napi->dev;
705 struct xcan_priv *priv = netdev_priv(ndev);
706 u32 isr, ier;
707 int work_done = 0;
708
709 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
710 while ((isr & XCAN_IXR_RXNEMP_MASK) && (work_done < quota)) {
32852c56 711 work_done += xcan_rx(ndev);
b1201e44
KA		 712 priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_RXNEMP_MASK);
713 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
714 }
715
716 if (work_done)
717 can_led_event(ndev, CAN_LED_EVENT_RX);
718
719 if (work_done < quota) {
6ad20165 720 napi_complete_done(napi, work_done);
b1201e44 721 ier = priv->read_reg(priv, XCAN_IER_OFFSET);
32852c56 722 ier |= XCAN_IXR_RXNEMP_MASK;
b1201e44
KA		 723 priv->write_reg(priv, XCAN_IER_OFFSET, ier);
724 }
725 return work_done;
726}
727
728/**
729 * xcan_tx_interrupt - Tx Done Isr
730 * @ndev: net_device pointer
731 * @isr: Interrupt status register value
732 */
733static void xcan_tx_interrupt(struct net_device *ndev, u32 isr)
734{
735 struct xcan_priv *priv = netdev_priv(ndev);
736 struct net_device_stats *stats = &ndev->stats;
737
738 while ((priv->tx_head - priv->tx_tail > 0) &&
739 (isr & XCAN_IXR_TXOK_MASK)) {
740 priv->write_reg(priv, XCAN_ICR_OFFSET, XCAN_IXR_TXOK_MASK);
741 can_get_echo_skb(ndev, priv->tx_tail %
742 priv->tx_max);
743 priv->tx_tail++;
744 stats->tx_packets++;
745 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
746 }
747 can_led_event(ndev, CAN_LED_EVENT_TX);
748 netif_wake_queue(ndev);
749}
750
751/**
752 * xcan_interrupt - CAN Isr
753 * @irq: irq number
754 * @dev_id: device id poniter
755 *
756 * This is the xilinx CAN Isr. It checks for the type of interrupt
757 * and invokes the corresponding ISR.
758 *
759 * Return:
760 * IRQ_NONE - If CAN device is in sleep mode, IRQ_HANDLED otherwise
761 */
762static irqreturn_t xcan_interrupt(int irq, void *dev_id)
763{
764 struct net_device *ndev = (struct net_device *)dev_id;
765 struct xcan_priv *priv = netdev_priv(ndev);
766 u32 isr, ier;
767
768 /* Get the interrupt status from Xilinx CAN */
769 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
770 if (!isr)
771 return IRQ_NONE;
772
773 /* Check for the type of interrupt and Processing it */
774 if (isr & (XCAN_IXR_SLP_MASK | XCAN_IXR_WKUP_MASK)) {
775 priv->write_reg(priv, XCAN_ICR_OFFSET, (XCAN_IXR_SLP_MASK |
776 XCAN_IXR_WKUP_MASK));
777 xcan_state_interrupt(ndev, isr);
778 }
779
780 /* Check for Tx interrupt and Processing it */
781 if (isr & XCAN_IXR_TXOK_MASK)
782 xcan_tx_interrupt(ndev, isr);
783
784 /* Check for the type of error interrupt and Processing it */
785 if (isr & (XCAN_IXR_ERROR_MASK | XCAN_IXR_RXOFLW_MASK |
786 XCAN_IXR_BSOFF_MASK | XCAN_IXR_ARBLST_MASK)) {
787 priv->write_reg(priv, XCAN_ICR_OFFSET, (XCAN_IXR_ERROR_MASK |
788 XCAN_IXR_RXOFLW_MASK | XCAN_IXR_BSOFF_MASK |
789 XCAN_IXR_ARBLST_MASK));
790 xcan_err_interrupt(ndev, isr);
791 }
792
793 /* Check for the type of receive interrupt and Processing it */
32852c56 794 if (isr & XCAN_IXR_RXNEMP_MASK) {
b1201e44 795 ier = priv->read_reg(priv, XCAN_IER_OFFSET);
32852c56 796 ier &= ~XCAN_IXR_RXNEMP_MASK;
b1201e44
KA		 797 priv->write_reg(priv, XCAN_IER_OFFSET, ier);
798 napi_schedule(&priv->napi);
799 }
800 return IRQ_HANDLED;
801}
802
803/**
804 * xcan_chip_stop - Driver stop routine
805 * @ndev: Pointer to net_device structure
806 *
807 * This is the drivers stop routine. It will disable the
808 * interrupts and put the device into configuration mode.
809 */
810static void xcan_chip_stop(struct net_device *ndev)
811{
812 struct xcan_priv *priv = netdev_priv(ndev);
813 u32 ier;
814
815 /* Disable interrupts and leave the can in configuration mode */
816 ier = priv->read_reg(priv, XCAN_IER_OFFSET);
817 ier &= ~XCAN_INTR_ALL;
818 priv->write_reg(priv, XCAN_IER_OFFSET, ier);
819 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
820 priv->can.state = CAN_STATE_STOPPED;
821}
822
823/**
824 * xcan_open - Driver open routine
825 * @ndev: Pointer to net_device structure
826 *
827 * This is the driver open routine.
828 * Return: 0 on success and failure value on error
829 */
830static int xcan_open(struct net_device *ndev)
831{
832 struct xcan_priv *priv = netdev_priv(ndev);
833 int ret;
834
4716620d
KA		 835 ret = pm_runtime_get_sync(priv->dev);
836 if (ret < 0) {
837 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
838 __func__, ret);
839 return ret;
840 }
841
b1201e44
KA		 842 ret = request_irq(ndev->irq, xcan_interrupt, priv->irq_flags,
843 ndev->name, ndev);
844 if (ret < 0) {
845 netdev_err(ndev, "irq allocation for CAN failed\n");
846 goto err;
847 }
848
b1201e44
KA		 849 /* Set chip into reset mode */
850 ret = set_reset_mode(ndev);
851 if (ret < 0) {
852 netdev_err(ndev, "mode resetting failed!\n");
4716620d 853 goto err_irq;
b1201e44
KA		 854 }
855
856 /* Common open */
857 ret = open_candev(ndev);
858 if (ret)
4716620d 859 goto err_irq;
b1201e44
KA		 860
861 ret = xcan_chip_start(ndev);
862 if (ret < 0) {
863 netdev_err(ndev, "xcan_chip_start failed!\n");
864 goto err_candev;
865 }
866
867 can_led_event(ndev, CAN_LED_EVENT_OPEN);
868 napi_enable(&priv->napi);
869 netif_start_queue(ndev);
870
871 return 0;
872
873err_candev:
874 close_candev(ndev);
b1201e44
KA		 875err_irq:
876 free_irq(ndev->irq, ndev);
877err:
4716620d
KA		 878 pm_runtime_put(priv->dev);
879
b1201e44
KA		 880 return ret;
881}
882
883/**
884 * xcan_close - Driver close routine
885 * @ndev: Pointer to net_device structure
886 *
887 * Return: 0 always
888 */
889static int xcan_close(struct net_device *ndev)
890{
891 struct xcan_priv *priv = netdev_priv(ndev);
892
893 netif_stop_queue(ndev);
894 napi_disable(&priv->napi);
895 xcan_chip_stop(ndev);
b1201e44
KA		 896 free_irq(ndev->irq, ndev);
897 close_candev(ndev);
898
899 can_led_event(ndev, CAN_LED_EVENT_STOP);
4716620d 900 pm_runtime_put(priv->dev);
b1201e44
KA		 901
902 return 0;
903}
904
905/**
906 * xcan_get_berr_counter - error counter routine
907 * @ndev: Pointer to net_device structure
908 * @bec: Pointer to can_berr_counter structure
909 *
910 * This is the driver error counter routine.
911 * Return: 0 on success and failure value on error
912 */
913static int xcan_get_berr_counter(const struct net_device *ndev,
914 struct can_berr_counter *bec)
915{
916 struct xcan_priv *priv = netdev_priv(ndev);
917 int ret;
918
4716620d
KA		 919 ret = pm_runtime_get_sync(priv->dev);
920 if (ret < 0) {
921 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
922 __func__, ret);
923 return ret;
924 }
b1201e44
KA		 925
926 bec->txerr = priv->read_reg(priv, XCAN_ECR_OFFSET) & XCAN_ECR_TEC_MASK;
927 bec->rxerr = ((priv->read_reg(priv, XCAN_ECR_OFFSET) &
928 XCAN_ECR_REC_MASK) >> XCAN_ESR_REC_SHIFT);
929
4716620d 930 pm_runtime_put(priv->dev);
b1201e44
KA		 931
932 return 0;
b1201e44
KA		 933}
934
935
936static const struct net_device_ops xcan_netdev_ops = {
937 .ndo_open = xcan_open,
938 .ndo_stop = xcan_close,
939 .ndo_start_xmit = xcan_start_xmit,
92593a03 940 .ndo_change_mtu = can_change_mtu,
b1201e44
KA		 941};
942
943/**
944 * xcan_suspend - Suspend method for the driver
4716620d 945 * @dev: Address of the device structure
b1201e44
KA		 946 *
947 * Put the driver into low power mode.
4716620d 948 * Return: 0 on success and failure value on error
b1201e44
KA		 949 */
950static int __maybe_unused xcan_suspend(struct device *dev)
951{
4716620d
KA		 952 if (!device_may_wakeup(dev))
953 return pm_runtime_force_suspend(dev);
954
955 return 0;
956}
957
958/**
959 * xcan_resume - Resume from suspend
960 * @dev: Address of the device structure
961 *
962 * Resume operation after suspend.
963 * Return: 0 on success and failure value on error
964 */
965static int __maybe_unused xcan_resume(struct device *dev)
966{
967 if (!device_may_wakeup(dev))
968 return pm_runtime_force_resume(dev);
969
970 return 0;
971
972}
973
974/**
975 * xcan_runtime_suspend - Runtime suspend method for the driver
976 * @dev: Address of the device structure
977 *
978 * Put the driver into low power mode.
979 * Return: 0 always
980 */
981static int __maybe_unused xcan_runtime_suspend(struct device *dev)
982{
983 struct net_device *ndev = dev_get_drvdata(dev);
b1201e44
KA		 984 struct xcan_priv *priv = netdev_priv(ndev);
985
986 if (netif_running(ndev)) {
987 netif_stop_queue(ndev);
988 netif_device_detach(ndev);
989 }
990
991 priv->write_reg(priv, XCAN_MSR_OFFSET, XCAN_MSR_SLEEP_MASK);
992 priv->can.state = CAN_STATE_SLEEPING;
993
4716620d
KA		 994 clk_disable_unprepare(priv->bus_clk);
995 clk_disable_unprepare(priv->can_clk);
b1201e44
KA		 996
997 return 0;
998}
999
1000/**
4716620d
KA		 1001 * xcan_runtime_resume - Runtime resume from suspend
1002 * @dev: Address of the device structure
b1201e44
KA		 1003 *
1004 * Resume operation after suspend.
1005 * Return: 0 on success and failure value on error
1006 */
4716620d 1007static int __maybe_unused xcan_runtime_resume(struct device *dev)
b1201e44 1008{
4716620d 1009 struct net_device *ndev = dev_get_drvdata(dev);
b1201e44
KA		 1010 struct xcan_priv *priv = netdev_priv(ndev);
1011 int ret;
4716620d 1012 u32 isr, status;
b1201e44 1013
4716620d 1014 ret = clk_prepare_enable(priv->bus_clk);
b1201e44
KA		 1015 if (ret) {
1016 dev_err(dev, "Cannot enable clock.\n");
1017 return ret;
1018 }
4716620d 1019 ret = clk_prepare_enable(priv->can_clk);
b1201e44
KA		 1020 if (ret) {
1021 dev_err(dev, "Cannot enable clock.\n");
1022 clk_disable_unprepare(priv->bus_clk);
1023 return ret;
1024 }
1025
4716620d
KA		 1026 priv->write_reg(priv, XCAN_SRR_OFFSET, XCAN_SRR_RESET_MASK);
1027 isr = priv->read_reg(priv, XCAN_ISR_OFFSET);
1028 status = priv->read_reg(priv, XCAN_SR_OFFSET);
b1201e44
KA		 1029
1030 if (netif_running(ndev)) {
4716620d
KA		 1031 if (isr & XCAN_IXR_BSOFF_MASK) {
1032 priv->can.state = CAN_STATE_BUS_OFF;
1033 priv->write_reg(priv, XCAN_SRR_OFFSET,
1034 XCAN_SRR_RESET_MASK);
1035 } else if ((status & XCAN_SR_ESTAT_MASK) ==
1036 XCAN_SR_ESTAT_MASK) {
1037 priv->can.state = CAN_STATE_ERROR_PASSIVE;
1038 } else if (status & XCAN_SR_ERRWRN_MASK) {
1039 priv->can.state = CAN_STATE_ERROR_WARNING;
1040 } else {
1041 priv->can.state = CAN_STATE_ERROR_ACTIVE;
1042 }
b1201e44
KA		 1043 netif_device_attach(ndev);
1044 netif_start_queue(ndev);
1045 }
1046
1047 return 0;
1048}
1049
4716620d
KA		 1050static const struct dev_pm_ops xcan_dev_pm_ops = {
1051 SET_SYSTEM_SLEEP_PM_OPS(xcan_suspend, xcan_resume)
1052 SET_RUNTIME_PM_OPS(xcan_runtime_suspend, xcan_runtime_resume, NULL)
1053};
b1201e44
KA		 1054
1055/**
1056 * xcan_probe - Platform registration call
1057 * @pdev: Handle to the platform device structure
1058 *
1059 * This function does all the memory allocation and registration for the CAN
1060 * device.
1061 *
1062 * Return: 0 on success and failure value on error
1063 */
1064static int xcan_probe(struct platform_device *pdev)
1065{
1066 struct resource *res; /* IO mem resources */
1067 struct net_device *ndev;
1068 struct xcan_priv *priv;
1069 void __iomem *addr;
1070 int ret, rx_max, tx_max;
1071
1072 /* Get the virtual base address for the device */
1073 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1074 addr = devm_ioremap_resource(&pdev->dev, res);
1075 if (IS_ERR(addr)) {
1076 ret = PTR_ERR(addr);
1077 goto err;
1078 }
1079
1080 ret = of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth", &tx_max);
1081 if (ret < 0)
1082 goto err;
1083
1084 ret = of_property_read_u32(pdev->dev.of_node, "rx-fifo-depth", &rx_max);
1085 if (ret < 0)
1086 goto err;
1087
1088 /* Create a CAN device instance */
1089 ndev = alloc_candev(sizeof(struct xcan_priv), tx_max);
1090 if (!ndev)
1091 return -ENOMEM;
1092
1093 priv = netdev_priv(ndev);
4716620d 1094 priv->dev = &pdev->dev;
b1201e44
KA		 1095 priv->can.bittiming_const = &xcan_bittiming_const;
1096 priv->can.do_set_mode = xcan_do_set_mode;
1097 priv->can.do_get_berr_counter = xcan_get_berr_counter;
1098 priv->can.ctrlmode_supported = CAN_CTRLMODE_LOOPBACK |
1099 CAN_CTRLMODE_BERR_REPORTING;
1100 priv->reg_base = addr;
1101 priv->tx_max = tx_max;
1102
1103 /* Get IRQ for the device */
1104 ndev->irq = platform_get_irq(pdev, 0);
1105 ndev->flags |= IFF_ECHO; /* We support local echo */
1106
1107 platform_set_drvdata(pdev, ndev);
1108 SET_NETDEV_DEV(ndev, &pdev->dev);
1109 ndev->netdev_ops = &xcan_netdev_ops;
1110
1111 /* Getting the CAN can_clk info */
1112 priv->can_clk = devm_clk_get(&pdev->dev, "can_clk");
1113 if (IS_ERR(priv->can_clk)) {
1114 dev_err(&pdev->dev, "Device clock not found.\n");
1115 ret = PTR_ERR(priv->can_clk);
1116 goto err_free;
1117 }
1118 /* Check for type of CAN device */
1119 if (of_device_is_compatible(pdev->dev.of_node,
1120 "xlnx,zynq-can-1.0")) {
1121 priv->bus_clk = devm_clk_get(&pdev->dev, "pclk");
1122 if (IS_ERR(priv->bus_clk)) {
1123 dev_err(&pdev->dev, "bus clock not found\n");
1124 ret = PTR_ERR(priv->bus_clk);
1125 goto err_free;
1126 }
1127 } else {
1128 priv->bus_clk = devm_clk_get(&pdev->dev, "s_axi_aclk");
1129 if (IS_ERR(priv->bus_clk)) {
1130 dev_err(&pdev->dev, "bus clock not found\n");
1131 ret = PTR_ERR(priv->bus_clk);
1132 goto err_free;
1133 }
1134 }
1135
b1201e44
KA		 1136 priv->write_reg = xcan_write_reg_le;
1137 priv->read_reg = xcan_read_reg_le;
1138
4716620d
KA		 1139 pm_runtime_enable(&pdev->dev);
1140 ret = pm_runtime_get_sync(&pdev->dev);
1141 if (ret < 0) {
1142 netdev_err(ndev, "%s: pm_runtime_get failed(%d)\n",
1143 __func__, ret);
1144 goto err_pmdisable;
1145 }
1146
b1201e44
KA		 1147 if (priv->read_reg(priv, XCAN_SR_OFFSET) != XCAN_SR_CONFIG_MASK) {
1148 priv->write_reg = xcan_write_reg_be;
1149 priv->read_reg = xcan_read_reg_be;
1150 }
1151
1152 priv->can.clock.freq = clk_get_rate(priv->can_clk);
1153
1154 netif_napi_add(ndev, &priv->napi, xcan_rx_poll, rx_max);
1155
1156 ret = register_candev(ndev);
1157 if (ret) {
1158 dev_err(&pdev->dev, "fail to register failed (err=%d)\n", ret);
4716620d 1159 goto err_disableclks;
b1201e44
KA		 1160 }
1161
1162 devm_can_led_init(ndev);
4716620d
KA		 1163
1164 pm_runtime_put(&pdev->dev);
1165
b1201e44
KA		 1166 netdev_dbg(ndev, "reg_base=0x%p irq=%d clock=%d, tx fifo depth:%d\n",
1167 priv->reg_base, ndev->irq, priv->can.clock.freq,
1168 priv->tx_max);
1169
1170 return 0;
1171
4716620d
KA		 1172err_disableclks:
1173 pm_runtime_put(priv->dev);
1174err_pmdisable:
1175 pm_runtime_disable(&pdev->dev);
b1201e44
KA		 1176err_free:
1177 free_candev(ndev);
1178err:
1179 return ret;
1180}
1181
1182/**
1183 * xcan_remove - Unregister the device after releasing the resources
1184 * @pdev: Handle to the platform device structure
1185 *
1186 * This function frees all the resources allocated to the device.
1187 * Return: 0 always
1188 */
1189static int xcan_remove(struct platform_device *pdev)
1190{
1191 struct net_device *ndev = platform_get_drvdata(pdev);
1192 struct xcan_priv *priv = netdev_priv(ndev);
1193
b1201e44 1194 unregister_candev(ndev);
4716620d 1195 pm_runtime_disable(&pdev->dev);
b1201e44
KA		 1196 netif_napi_del(&priv->napi);
1197 free_candev(ndev);
1198
1199 return 0;
1200}
1201
1202/* Match table for OF platform binding */
486e9570 1203static const struct of_device_id xcan_of_match[] = {
b1201e44
KA		 1204 { .compatible = "xlnx,zynq-can-1.0", },
1205 { .compatible = "xlnx,axi-can-1.00.a", },
1206 { /* end of list */ },
1207};
1208MODULE_DEVICE_TABLE(of, xcan_of_match);
1209
1210static struct platform_driver xcan_driver = {
1211 .probe = xcan_probe,
1212 .remove = xcan_remove,
1213 .driver = {
b1201e44
KA		 1214 .name = DRIVER_NAME,
1215 .pm = &xcan_dev_pm_ops,
1216 .of_match_table = xcan_of_match,
1217 },
1218};
1219
1220module_platform_driver(xcan_driver);
1221
1222MODULE_LICENSE("GPL");
1223MODULE_AUTHOR("Xilinx Inc");
1224MODULE_DESCRIPTION("Xilinx CAN interface");
Linux 6.x block layer and io_uring tree(s)