xref: /openbmc/linux/drivers/net/can/ti_hecc.c (revision 2e3df4a3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * TI HECC (CAN) device driver
4  *
5  * This driver supports TI's HECC (High End CAN Controller module) and the
6  * specs for the same is available at <http://www.ti.com>
7  *
8  * Copyright (C) 2009 Texas Instruments Incorporated - http://www.ti.com/
9  * Copyright (C) 2019 Jeroen Hofstee <jhofstee@victronenergy.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/kernel.h>
14 #include <linux/types.h>
15 #include <linux/interrupt.h>
16 #include <linux/errno.h>
17 #include <linux/ethtool.h>
18 #include <linux/netdevice.h>
19 #include <linux/skbuff.h>
20 #include <linux/platform_device.h>
21 #include <linux/clk.h>
22 #include <linux/io.h>
23 #include <linux/of.h>
24 #include <linux/regulator/consumer.h>
25 
26 #include <linux/can/dev.h>
27 #include <linux/can/error.h>
28 #include <linux/can/rx-offload.h>
29 
30 #define DRV_NAME "ti_hecc"
31 #define HECC_MODULE_VERSION     "0.7"
32 MODULE_VERSION(HECC_MODULE_VERSION);
33 #define DRV_DESC "TI High End CAN Controller Driver " HECC_MODULE_VERSION
34 
35 /* TX / RX Mailbox Configuration */
36 #define HECC_MAX_MAILBOXES	32	/* hardware mailboxes - do not change */
37 #define MAX_TX_PRIO		0x3F	/* hardware value - do not change */
38 
39 /* Important Note: TX mailbox configuration
40  * TX mailboxes should be restricted to the number of SKB buffers to avoid
41  * maintaining SKB buffers separately. TX mailboxes should be a power of 2
42  * for the mailbox logic to work.  Top mailbox numbers are reserved for RX
43  * and lower mailboxes for TX.
44  *
45  * HECC_MAX_TX_MBOX	HECC_MB_TX_SHIFT
46  * 4 (default)		2
47  * 8			3
48  * 16			4
49  */
50 #define HECC_MB_TX_SHIFT	2 /* as per table above */
51 #define HECC_MAX_TX_MBOX	BIT(HECC_MB_TX_SHIFT)
52 
53 #define HECC_TX_PRIO_SHIFT	(HECC_MB_TX_SHIFT)
54 #define HECC_TX_PRIO_MASK	(MAX_TX_PRIO << HECC_MB_TX_SHIFT)
55 #define HECC_TX_MB_MASK		(HECC_MAX_TX_MBOX - 1)
56 #define HECC_TX_MASK		((HECC_MAX_TX_MBOX - 1) | HECC_TX_PRIO_MASK)
57 
58 /* RX mailbox configuration
59  *
60  * The remaining mailboxes are used for reception and are delivered
61  * based on their timestamp, to avoid a hardware race when CANME is
62  * changed while CAN-bus traffic is being received.
63  */
64 #define HECC_MAX_RX_MBOX	(HECC_MAX_MAILBOXES - HECC_MAX_TX_MBOX)
65 #define HECC_RX_FIRST_MBOX	(HECC_MAX_MAILBOXES - 1)
66 #define HECC_RX_LAST_MBOX	(HECC_MAX_TX_MBOX)
67 
68 /* TI HECC module registers */
69 #define HECC_CANME		0x0	/* Mailbox enable */
70 #define HECC_CANMD		0x4	/* Mailbox direction */
71 #define HECC_CANTRS		0x8	/* Transmit request set */
72 #define HECC_CANTRR		0xC	/* Transmit request */
73 #define HECC_CANTA		0x10	/* Transmission acknowledge */
74 #define HECC_CANAA		0x14	/* Abort acknowledge */
75 #define HECC_CANRMP		0x18	/* Receive message pending */
76 #define HECC_CANRML		0x1C	/* Receive message lost */
77 #define HECC_CANRFP		0x20	/* Remote frame pending */
78 #define HECC_CANGAM		0x24	/* SECC only:Global acceptance mask */
79 #define HECC_CANMC		0x28	/* Master control */
80 #define HECC_CANBTC		0x2C	/* Bit timing configuration */
81 #define HECC_CANES		0x30	/* Error and status */
82 #define HECC_CANTEC		0x34	/* Transmit error counter */
83 #define HECC_CANREC		0x38	/* Receive error counter */
84 #define HECC_CANGIF0		0x3C	/* Global interrupt flag 0 */
85 #define HECC_CANGIM		0x40	/* Global interrupt mask */
86 #define HECC_CANGIF1		0x44	/* Global interrupt flag 1 */
87 #define HECC_CANMIM		0x48	/* Mailbox interrupt mask */
88 #define HECC_CANMIL		0x4C	/* Mailbox interrupt level */
89 #define HECC_CANOPC		0x50	/* Overwrite protection control */
90 #define HECC_CANTIOC		0x54	/* Transmit I/O control */
91 #define HECC_CANRIOC		0x58	/* Receive I/O control */
92 #define HECC_CANLNT		0x5C	/* HECC only: Local network time */
93 #define HECC_CANTOC		0x60	/* HECC only: Time-out control */
94 #define HECC_CANTOS		0x64	/* HECC only: Time-out status */
95 #define HECC_CANTIOCE		0x68	/* SCC only:Enhanced TX I/O control */
96 #define HECC_CANRIOCE		0x6C	/* SCC only:Enhanced RX I/O control */
97 
98 /* TI HECC RAM registers */
99 #define HECC_CANMOTS		0x80	/* Message object time stamp */
100 
101 /* Mailbox registers */
102 #define HECC_CANMID		0x0
103 #define HECC_CANMCF		0x4
104 #define HECC_CANMDL		0x8
105 #define HECC_CANMDH		0xC
106 
107 #define HECC_SET_REG		0xFFFFFFFF
108 #define HECC_CANID_MASK		0x3FF	/* 18 bits mask for extended id's */
109 #define HECC_CCE_WAIT_COUNT     100	/* Wait for ~1 sec for CCE bit */
110 
111 #define HECC_CANMC_SCM		BIT(13)	/* SCC compat mode */
112 #define HECC_CANMC_CCR		BIT(12)	/* Change config request */
113 #define HECC_CANMC_PDR		BIT(11)	/* Local Power down - for sleep mode */
114 #define HECC_CANMC_ABO		BIT(7)	/* Auto Bus On */
115 #define HECC_CANMC_STM		BIT(6)	/* Self test mode - loopback */
116 #define HECC_CANMC_SRES		BIT(5)	/* Software reset */
117 
118 #define HECC_CANTIOC_EN		BIT(3)	/* Enable CAN TX I/O pin */
119 #define HECC_CANRIOC_EN		BIT(3)	/* Enable CAN RX I/O pin */
120 
121 #define HECC_CANMID_IDE		BIT(31)	/* Extended frame format */
122 #define HECC_CANMID_AME		BIT(30)	/* Acceptance mask enable */
123 #define HECC_CANMID_AAM		BIT(29)	/* Auto answer mode */
124 
125 #define HECC_CANES_FE		BIT(24)	/* form error */
126 #define HECC_CANES_BE		BIT(23)	/* bit error */
127 #define HECC_CANES_SA1		BIT(22)	/* stuck at dominant error */
128 #define HECC_CANES_CRCE		BIT(21)	/* CRC error */
129 #define HECC_CANES_SE		BIT(20)	/* stuff bit error */
130 #define HECC_CANES_ACKE		BIT(19)	/* ack error */
131 #define HECC_CANES_BO		BIT(18)	/* Bus off status */
132 #define HECC_CANES_EP		BIT(17)	/* Error passive status */
133 #define HECC_CANES_EW		BIT(16)	/* Error warning status */
134 #define HECC_CANES_SMA		BIT(5)	/* suspend mode ack */
135 #define HECC_CANES_CCE		BIT(4)	/* Change config enabled */
136 #define HECC_CANES_PDA		BIT(3)	/* Power down mode ack */
137 
138 #define HECC_CANBTC_SAM		BIT(7)	/* sample points */
139 
140 #define HECC_BUS_ERROR		(HECC_CANES_FE | HECC_CANES_BE |\
141 				HECC_CANES_CRCE | HECC_CANES_SE |\
142 				HECC_CANES_ACKE)
143 #define HECC_CANES_FLAGS	(HECC_BUS_ERROR | HECC_CANES_BO |\
144 				HECC_CANES_EP | HECC_CANES_EW)
145 
146 #define HECC_CANMCF_RTR		BIT(4)	/* Remote transmit request */
147 
148 #define HECC_CANGIF_MAIF	BIT(17)	/* Message alarm interrupt */
149 #define HECC_CANGIF_TCOIF	BIT(16) /* Timer counter overflow int */
150 #define HECC_CANGIF_GMIF	BIT(15)	/* Global mailbox interrupt */
151 #define HECC_CANGIF_AAIF	BIT(14)	/* Abort ack interrupt */
152 #define HECC_CANGIF_WDIF	BIT(13)	/* Write denied interrupt */
153 #define HECC_CANGIF_WUIF	BIT(12)	/* Wake up interrupt */
154 #define HECC_CANGIF_RMLIF	BIT(11)	/* Receive message lost interrupt */
155 #define HECC_CANGIF_BOIF	BIT(10)	/* Bus off interrupt */
156 #define HECC_CANGIF_EPIF	BIT(9)	/* Error passive interrupt */
157 #define HECC_CANGIF_WLIF	BIT(8)	/* Warning level interrupt */
158 #define HECC_CANGIF_MBOX_MASK	0x1F	/* Mailbox number mask */
159 #define HECC_CANGIM_I1EN	BIT(1)	/* Int line 1 enable */
160 #define HECC_CANGIM_I0EN	BIT(0)	/* Int line 0 enable */
161 #define HECC_CANGIM_DEF_MASK	0x700	/* only busoff/warning/passive */
162 #define HECC_CANGIM_SIL		BIT(2)	/* system interrupts to int line 1 */
163 
164 /* CAN Bittiming constants as per HECC specs */
165 static const struct can_bittiming_const ti_hecc_bittiming_const = {
166 	.name = DRV_NAME,
167 	.tseg1_min = 1,
168 	.tseg1_max = 16,
169 	.tseg2_min = 1,
170 	.tseg2_max = 8,
171 	.sjw_max = 4,
172 	.brp_min = 1,
173 	.brp_max = 256,
174 	.brp_inc = 1,
175 };
176 
177 struct ti_hecc_priv {
178 	struct can_priv can;	/* MUST be first member/field */
179 	struct can_rx_offload offload;
180 	struct net_device *ndev;
181 	struct clk *clk;
182 	void __iomem *base;
183 	void __iomem *hecc_ram;
184 	void __iomem *mbx;
185 	bool use_hecc1int;
186 	spinlock_t mbx_lock; /* CANME register needs protection */
187 	u32 tx_head;
188 	u32 tx_tail;
189 	struct regulator *reg_xceiver;
190 };
191 
get_tx_head_mb(struct ti_hecc_priv * priv)192 static inline int get_tx_head_mb(struct ti_hecc_priv *priv)
193 {
194 	return priv->tx_head & HECC_TX_MB_MASK;
195 }
196 
get_tx_tail_mb(struct ti_hecc_priv * priv)197 static inline int get_tx_tail_mb(struct ti_hecc_priv *priv)
198 {
199 	return priv->tx_tail & HECC_TX_MB_MASK;
200 }
201 
get_tx_head_prio(struct ti_hecc_priv * priv)202 static inline int get_tx_head_prio(struct ti_hecc_priv *priv)
203 {
204 	return (priv->tx_head >> HECC_TX_PRIO_SHIFT) & MAX_TX_PRIO;
205 }
206 
hecc_write_lam(struct ti_hecc_priv * priv,u32 mbxno,u32 val)207 static inline void hecc_write_lam(struct ti_hecc_priv *priv, u32 mbxno, u32 val)
208 {
209 	__raw_writel(val, priv->hecc_ram + mbxno * 4);
210 }
211 
hecc_read_stamp(struct ti_hecc_priv * priv,u32 mbxno)212 static inline u32 hecc_read_stamp(struct ti_hecc_priv *priv, u32 mbxno)
213 {
214 	return __raw_readl(priv->hecc_ram + HECC_CANMOTS + mbxno * 4);
215 }
216 
hecc_write_mbx(struct ti_hecc_priv * priv,u32 mbxno,u32 reg,u32 val)217 static inline void hecc_write_mbx(struct ti_hecc_priv *priv, u32 mbxno,
218 				  u32 reg, u32 val)
219 {
220 	__raw_writel(val, priv->mbx + mbxno * 0x10 + reg);
221 }
222 
hecc_read_mbx(struct ti_hecc_priv * priv,u32 mbxno,u32 reg)223 static inline u32 hecc_read_mbx(struct ti_hecc_priv *priv, u32 mbxno, u32 reg)
224 {
225 	return __raw_readl(priv->mbx + mbxno * 0x10 + reg);
226 }
227 
hecc_write(struct ti_hecc_priv * priv,u32 reg,u32 val)228 static inline void hecc_write(struct ti_hecc_priv *priv, u32 reg, u32 val)
229 {
230 	__raw_writel(val, priv->base + reg);
231 }
232 
hecc_read(struct ti_hecc_priv * priv,int reg)233 static inline u32 hecc_read(struct ti_hecc_priv *priv, int reg)
234 {
235 	return __raw_readl(priv->base + reg);
236 }
237 
hecc_set_bit(struct ti_hecc_priv * priv,int reg,u32 bit_mask)238 static inline void hecc_set_bit(struct ti_hecc_priv *priv, int reg,
239 				u32 bit_mask)
240 {
241 	hecc_write(priv, reg, hecc_read(priv, reg) | bit_mask);
242 }
243 
hecc_clear_bit(struct ti_hecc_priv * priv,int reg,u32 bit_mask)244 static inline void hecc_clear_bit(struct ti_hecc_priv *priv, int reg,
245 				  u32 bit_mask)
246 {
247 	hecc_write(priv, reg, hecc_read(priv, reg) & ~bit_mask);
248 }
249 
hecc_get_bit(struct ti_hecc_priv * priv,int reg,u32 bit_mask)250 static inline u32 hecc_get_bit(struct ti_hecc_priv *priv, int reg, u32 bit_mask)
251 {
252 	return (hecc_read(priv, reg) & bit_mask) ? 1 : 0;
253 }
254 
ti_hecc_set_btc(struct ti_hecc_priv * priv)255 static int ti_hecc_set_btc(struct ti_hecc_priv *priv)
256 {
257 	struct can_bittiming *bit_timing = &priv->can.bittiming;
258 	u32 can_btc;
259 
260 	can_btc = (bit_timing->phase_seg2 - 1) & 0x7;
261 	can_btc |= ((bit_timing->phase_seg1 + bit_timing->prop_seg - 1)
262 			& 0xF) << 3;
263 	if (priv->can.ctrlmode & CAN_CTRLMODE_3_SAMPLES) {
264 		if (bit_timing->brp > 4)
265 			can_btc |= HECC_CANBTC_SAM;
266 		else
267 			netdev_warn(priv->ndev,
268 				    "WARN: Triple sampling not set due to h/w limitations");
269 	}
270 	can_btc |= ((bit_timing->sjw - 1) & 0x3) << 8;
271 	can_btc |= ((bit_timing->brp - 1) & 0xFF) << 16;
272 
273 	/* ERM being set to 0 by default meaning resync at falling edge */
274 
275 	hecc_write(priv, HECC_CANBTC, can_btc);
276 	netdev_info(priv->ndev, "setting CANBTC=%#x\n", can_btc);
277 
278 	return 0;
279 }
280 
ti_hecc_transceiver_switch(const struct ti_hecc_priv * priv,int on)281 static int ti_hecc_transceiver_switch(const struct ti_hecc_priv *priv,
282 				      int on)
283 {
284 	if (!priv->reg_xceiver)
285 		return 0;
286 
287 	if (on)
288 		return regulator_enable(priv->reg_xceiver);
289 	else
290 		return regulator_disable(priv->reg_xceiver);
291 }
292 
ti_hecc_reset(struct net_device * ndev)293 static void ti_hecc_reset(struct net_device *ndev)
294 {
295 	u32 cnt;
296 	struct ti_hecc_priv *priv = netdev_priv(ndev);
297 
298 	netdev_dbg(ndev, "resetting hecc ...\n");
299 	hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_SRES);
300 
301 	/* Set change control request and wait till enabled */
302 	hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_CCR);
303 
304 	/* INFO: It has been observed that at times CCE bit may not be
305 	 * set and hw seems to be ok even if this bit is not set so
306 	 * timing out with a timing of 1ms to respect the specs
307 	 */
308 	cnt = HECC_CCE_WAIT_COUNT;
309 	while (!hecc_get_bit(priv, HECC_CANES, HECC_CANES_CCE) && cnt != 0) {
310 		--cnt;
311 		udelay(10);
312 	}
313 
314 	/* Note: On HECC, BTC can be programmed only in initialization mode, so
315 	 * it is expected that the can bittiming parameters are set via ip
316 	 * utility before the device is opened
317 	 */
318 	ti_hecc_set_btc(priv);
319 
320 	/* Clear CCR (and CANMC register) and wait for CCE = 0 enable */
321 	hecc_write(priv, HECC_CANMC, 0);
322 
323 	/* INFO: CAN net stack handles bus off and hence disabling auto-bus-on
324 	 * hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_ABO);
325 	 */
326 
327 	/* INFO: It has been observed that at times CCE bit may not be
328 	 * set and hw seems to be ok even if this bit is not set so
329 	 */
330 	cnt = HECC_CCE_WAIT_COUNT;
331 	while (hecc_get_bit(priv, HECC_CANES, HECC_CANES_CCE) && cnt != 0) {
332 		--cnt;
333 		udelay(10);
334 	}
335 
336 	/* Enable TX and RX I/O Control pins */
337 	hecc_write(priv, HECC_CANTIOC, HECC_CANTIOC_EN);
338 	hecc_write(priv, HECC_CANRIOC, HECC_CANRIOC_EN);
339 
340 	/* Clear registers for clean operation */
341 	hecc_write(priv, HECC_CANTA, HECC_SET_REG);
342 	hecc_write(priv, HECC_CANRMP, HECC_SET_REG);
343 	hecc_write(priv, HECC_CANGIF0, HECC_SET_REG);
344 	hecc_write(priv, HECC_CANGIF1, HECC_SET_REG);
345 	hecc_write(priv, HECC_CANME, 0);
346 	hecc_write(priv, HECC_CANMD, 0);
347 
348 	/* SCC compat mode NOT supported (and not needed too) */
349 	hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_SCM);
350 }
351 
ti_hecc_start(struct net_device * ndev)352 static void ti_hecc_start(struct net_device *ndev)
353 {
354 	struct ti_hecc_priv *priv = netdev_priv(ndev);
355 	u32 cnt, mbxno, mbx_mask;
356 
357 	/* put HECC in initialization mode and set btc */
358 	ti_hecc_reset(ndev);
359 
360 	priv->tx_head = HECC_TX_MASK;
361 	priv->tx_tail = HECC_TX_MASK;
362 
363 	/* Enable local and global acceptance mask registers */
364 	hecc_write(priv, HECC_CANGAM, HECC_SET_REG);
365 
366 	/* Prepare configured mailboxes to receive messages */
367 	for (cnt = 0; cnt < HECC_MAX_RX_MBOX; cnt++) {
368 		mbxno = HECC_MAX_MAILBOXES - 1 - cnt;
369 		mbx_mask = BIT(mbxno);
370 		hecc_clear_bit(priv, HECC_CANME, mbx_mask);
371 		hecc_write_mbx(priv, mbxno, HECC_CANMID, HECC_CANMID_AME);
372 		hecc_write_lam(priv, mbxno, HECC_SET_REG);
373 		hecc_set_bit(priv, HECC_CANMD, mbx_mask);
374 		hecc_set_bit(priv, HECC_CANME, mbx_mask);
375 		hecc_set_bit(priv, HECC_CANMIM, mbx_mask);
376 	}
377 
378 	/* Enable tx interrupts */
379 	hecc_set_bit(priv, HECC_CANMIM, BIT(HECC_MAX_TX_MBOX) - 1);
380 
381 	/* Prevent message over-write to create a rx fifo, but not for
382 	 * the lowest priority mailbox, since that allows detecting
383 	 * overflows instead of the hardware silently dropping the
384 	 * messages.
385 	 */
386 	mbx_mask = ~BIT(HECC_RX_LAST_MBOX);
387 	hecc_write(priv, HECC_CANOPC, mbx_mask);
388 
389 	/* Enable interrupts */
390 	if (priv->use_hecc1int) {
391 		hecc_write(priv, HECC_CANMIL, HECC_SET_REG);
392 		hecc_write(priv, HECC_CANGIM, HECC_CANGIM_DEF_MASK |
393 			HECC_CANGIM_I1EN | HECC_CANGIM_SIL);
394 	} else {
395 		hecc_write(priv, HECC_CANMIL, 0);
396 		hecc_write(priv, HECC_CANGIM,
397 			   HECC_CANGIM_DEF_MASK | HECC_CANGIM_I0EN);
398 	}
399 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
400 }
401 
ti_hecc_stop(struct net_device * ndev)402 static void ti_hecc_stop(struct net_device *ndev)
403 {
404 	struct ti_hecc_priv *priv = netdev_priv(ndev);
405 
406 	/* Disable the CPK; stop sending, erroring and acking */
407 	hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_CCR);
408 
409 	/* Disable interrupts and disable mailboxes */
410 	hecc_write(priv, HECC_CANGIM, 0);
411 	hecc_write(priv, HECC_CANMIM, 0);
412 	hecc_write(priv, HECC_CANME, 0);
413 	priv->can.state = CAN_STATE_STOPPED;
414 }
415 
ti_hecc_do_set_mode(struct net_device * ndev,enum can_mode mode)416 static int ti_hecc_do_set_mode(struct net_device *ndev, enum can_mode mode)
417 {
418 	int ret = 0;
419 
420 	switch (mode) {
421 	case CAN_MODE_START:
422 		ti_hecc_start(ndev);
423 		netif_wake_queue(ndev);
424 		break;
425 	default:
426 		ret = -EOPNOTSUPP;
427 		break;
428 	}
429 
430 	return ret;
431 }
432 
ti_hecc_get_berr_counter(const struct net_device * ndev,struct can_berr_counter * bec)433 static int ti_hecc_get_berr_counter(const struct net_device *ndev,
434 				    struct can_berr_counter *bec)
435 {
436 	struct ti_hecc_priv *priv = netdev_priv(ndev);
437 
438 	bec->txerr = hecc_read(priv, HECC_CANTEC);
439 	bec->rxerr = hecc_read(priv, HECC_CANREC);
440 
441 	return 0;
442 }
443 
444 /* ti_hecc_xmit: HECC Transmit
445  *
446  * The transmit mailboxes start from 0 to HECC_MAX_TX_MBOX. In HECC the
447  * priority of the mailbox for transmission is dependent upon priority setting
448  * field in mailbox registers. The mailbox with highest value in priority field
449  * is transmitted first. Only when two mailboxes have the same value in
450  * priority field the highest numbered mailbox is transmitted first.
451  *
452  * To utilize the HECC priority feature as described above we start with the
453  * highest numbered mailbox with highest priority level and move on to the next
454  * mailbox with the same priority level and so on. Once we loop through all the
455  * transmit mailboxes we choose the next priority level (lower) and so on
456  * until we reach the lowest priority level on the lowest numbered mailbox
457  * when we stop transmission until all mailboxes are transmitted and then
458  * restart at highest numbered mailbox with highest priority.
459  *
460  * Two counters (head and tail) are used to track the next mailbox to transmit
461  * and to track the echo buffer for already transmitted mailbox. The queue
462  * is stopped when all the mailboxes are busy or when there is a priority
463  * value roll-over happens.
464  */
ti_hecc_xmit(struct sk_buff * skb,struct net_device * ndev)465 static netdev_tx_t ti_hecc_xmit(struct sk_buff *skb, struct net_device *ndev)
466 {
467 	struct ti_hecc_priv *priv = netdev_priv(ndev);
468 	struct can_frame *cf = (struct can_frame *)skb->data;
469 	u32 mbxno, mbx_mask, data;
470 	unsigned long flags;
471 
472 	if (can_dev_dropped_skb(ndev, skb))
473 		return NETDEV_TX_OK;
474 
475 	mbxno = get_tx_head_mb(priv);
476 	mbx_mask = BIT(mbxno);
477 	spin_lock_irqsave(&priv->mbx_lock, flags);
478 	if (unlikely(hecc_read(priv, HECC_CANME) & mbx_mask)) {
479 		spin_unlock_irqrestore(&priv->mbx_lock, flags);
480 		netif_stop_queue(ndev);
481 		netdev_err(priv->ndev,
482 			   "BUG: TX mbx not ready tx_head=%08X, tx_tail=%08X\n",
483 			   priv->tx_head, priv->tx_tail);
484 		return NETDEV_TX_BUSY;
485 	}
486 	spin_unlock_irqrestore(&priv->mbx_lock, flags);
487 
488 	/* Prepare mailbox for transmission */
489 	data = cf->len | (get_tx_head_prio(priv) << 8);
490 	if (cf->can_id & CAN_RTR_FLAG) /* Remote transmission request */
491 		data |= HECC_CANMCF_RTR;
492 	hecc_write_mbx(priv, mbxno, HECC_CANMCF, data);
493 
494 	if (cf->can_id & CAN_EFF_FLAG) /* Extended frame format */
495 		data = (cf->can_id & CAN_EFF_MASK) | HECC_CANMID_IDE;
496 	else /* Standard frame format */
497 		data = (cf->can_id & CAN_SFF_MASK) << 18;
498 	hecc_write_mbx(priv, mbxno, HECC_CANMID, data);
499 	hecc_write_mbx(priv, mbxno, HECC_CANMDL,
500 		       be32_to_cpu(*(__be32 *)(cf->data)));
501 	if (cf->len > 4)
502 		hecc_write_mbx(priv, mbxno, HECC_CANMDH,
503 			       be32_to_cpu(*(__be32 *)(cf->data + 4)));
504 	else
505 		*(u32 *)(cf->data + 4) = 0;
506 	can_put_echo_skb(skb, ndev, mbxno, 0);
507 
508 	spin_lock_irqsave(&priv->mbx_lock, flags);
509 	--priv->tx_head;
510 	if ((hecc_read(priv, HECC_CANME) & BIT(get_tx_head_mb(priv))) ||
511 	    (priv->tx_head & HECC_TX_MASK) == HECC_TX_MASK) {
512 		netif_stop_queue(ndev);
513 	}
514 	hecc_set_bit(priv, HECC_CANME, mbx_mask);
515 	spin_unlock_irqrestore(&priv->mbx_lock, flags);
516 
517 	hecc_write(priv, HECC_CANTRS, mbx_mask);
518 
519 	return NETDEV_TX_OK;
520 }
521 
522 static inline
rx_offload_to_priv(struct can_rx_offload * offload)523 struct ti_hecc_priv *rx_offload_to_priv(struct can_rx_offload *offload)
524 {
525 	return container_of(offload, struct ti_hecc_priv, offload);
526 }
527 
ti_hecc_mailbox_read(struct can_rx_offload * offload,unsigned int mbxno,u32 * timestamp,bool drop)528 static struct sk_buff *ti_hecc_mailbox_read(struct can_rx_offload *offload,
529 					    unsigned int mbxno, u32 *timestamp,
530 					    bool drop)
531 {
532 	struct ti_hecc_priv *priv = rx_offload_to_priv(offload);
533 	struct sk_buff *skb;
534 	struct can_frame *cf;
535 	u32 data, mbx_mask;
536 
537 	mbx_mask = BIT(mbxno);
538 
539 	if (unlikely(drop)) {
540 		skb = ERR_PTR(-ENOBUFS);
541 		goto mark_as_read;
542 	}
543 
544 	skb = alloc_can_skb(offload->dev, &cf);
545 	if (unlikely(!skb)) {
546 		skb = ERR_PTR(-ENOMEM);
547 		goto mark_as_read;
548 	}
549 
550 	data = hecc_read_mbx(priv, mbxno, HECC_CANMID);
551 	if (data & HECC_CANMID_IDE)
552 		cf->can_id = (data & CAN_EFF_MASK) | CAN_EFF_FLAG;
553 	else
554 		cf->can_id = (data >> 18) & CAN_SFF_MASK;
555 
556 	data = hecc_read_mbx(priv, mbxno, HECC_CANMCF);
557 	if (data & HECC_CANMCF_RTR)
558 		cf->can_id |= CAN_RTR_FLAG;
559 	cf->len = can_cc_dlc2len(data & 0xF);
560 
561 	data = hecc_read_mbx(priv, mbxno, HECC_CANMDL);
562 	*(__be32 *)(cf->data) = cpu_to_be32(data);
563 	if (cf->len > 4) {
564 		data = hecc_read_mbx(priv, mbxno, HECC_CANMDH);
565 		*(__be32 *)(cf->data + 4) = cpu_to_be32(data);
566 	}
567 
568 	*timestamp = hecc_read_stamp(priv, mbxno);
569 
570 	/* Check for FIFO overrun.
571 	 *
572 	 * All but the last RX mailbox have activated overwrite
573 	 * protection. So skip check for overrun, if we're not
574 	 * handling the last RX mailbox.
575 	 *
576 	 * As the overwrite protection for the last RX mailbox is
577 	 * disabled, the CAN core might update while we're reading
578 	 * it. This means the skb might be inconsistent.
579 	 *
580 	 * Return an error to let rx-offload discard this CAN frame.
581 	 */
582 	if (unlikely(mbxno == HECC_RX_LAST_MBOX &&
583 		     hecc_read(priv, HECC_CANRML) & mbx_mask))
584 		skb = ERR_PTR(-ENOBUFS);
585 
586  mark_as_read:
587 	hecc_write(priv, HECC_CANRMP, mbx_mask);
588 
589 	return skb;
590 }
591 
ti_hecc_error(struct net_device * ndev,int int_status,int err_status)592 static int ti_hecc_error(struct net_device *ndev, int int_status,
593 			 int err_status)
594 {
595 	struct ti_hecc_priv *priv = netdev_priv(ndev);
596 	struct can_frame *cf;
597 	struct sk_buff *skb;
598 	u32 timestamp;
599 	int err;
600 
601 	if (err_status & HECC_BUS_ERROR) {
602 		/* propagate the error condition to the can stack */
603 		skb = alloc_can_err_skb(ndev, &cf);
604 		if (!skb) {
605 			if (net_ratelimit())
606 				netdev_err(priv->ndev,
607 					   "%s: alloc_can_err_skb() failed\n",
608 					   __func__);
609 			return -ENOMEM;
610 		}
611 
612 		++priv->can.can_stats.bus_error;
613 		cf->can_id |= CAN_ERR_BUSERROR | CAN_ERR_PROT;
614 		if (err_status & HECC_CANES_FE)
615 			cf->data[2] |= CAN_ERR_PROT_FORM;
616 		if (err_status & HECC_CANES_BE)
617 			cf->data[2] |= CAN_ERR_PROT_BIT;
618 		if (err_status & HECC_CANES_SE)
619 			cf->data[2] |= CAN_ERR_PROT_STUFF;
620 		if (err_status & HECC_CANES_CRCE)
621 			cf->data[3] = CAN_ERR_PROT_LOC_CRC_SEQ;
622 		if (err_status & HECC_CANES_ACKE)
623 			cf->data[3] = CAN_ERR_PROT_LOC_ACK;
624 
625 		timestamp = hecc_read(priv, HECC_CANLNT);
626 		err = can_rx_offload_queue_timestamp(&priv->offload, skb,
627 						     timestamp);
628 		if (err)
629 			ndev->stats.rx_fifo_errors++;
630 	}
631 
632 	hecc_write(priv, HECC_CANES, HECC_CANES_FLAGS);
633 
634 	return 0;
635 }
636 
ti_hecc_change_state(struct net_device * ndev,enum can_state rx_state,enum can_state tx_state)637 static void ti_hecc_change_state(struct net_device *ndev,
638 				 enum can_state rx_state,
639 				 enum can_state tx_state)
640 {
641 	struct ti_hecc_priv *priv = netdev_priv(ndev);
642 	struct can_frame *cf;
643 	struct sk_buff *skb;
644 	u32 timestamp;
645 	int err;
646 
647 	skb = alloc_can_err_skb(priv->ndev, &cf);
648 	if (unlikely(!skb)) {
649 		priv->can.state = max(tx_state, rx_state);
650 		return;
651 	}
652 
653 	can_change_state(priv->ndev, cf, tx_state, rx_state);
654 
655 	if (max(tx_state, rx_state) != CAN_STATE_BUS_OFF) {
656 		cf->can_id |= CAN_ERR_CNT;
657 		cf->data[6] = hecc_read(priv, HECC_CANTEC);
658 		cf->data[7] = hecc_read(priv, HECC_CANREC);
659 	}
660 
661 	timestamp = hecc_read(priv, HECC_CANLNT);
662 	err = can_rx_offload_queue_timestamp(&priv->offload, skb, timestamp);
663 	if (err)
664 		ndev->stats.rx_fifo_errors++;
665 }
666 
ti_hecc_interrupt(int irq,void * dev_id)667 static irqreturn_t ti_hecc_interrupt(int irq, void *dev_id)
668 {
669 	struct net_device *ndev = (struct net_device *)dev_id;
670 	struct ti_hecc_priv *priv = netdev_priv(ndev);
671 	struct net_device_stats *stats = &ndev->stats;
672 	u32 mbxno, mbx_mask, int_status, err_status, stamp;
673 	unsigned long flags, rx_pending;
674 	u32 handled = 0;
675 
676 	int_status = hecc_read(priv,
677 			       priv->use_hecc1int ?
678 			       HECC_CANGIF1 : HECC_CANGIF0);
679 
680 	if (!int_status)
681 		return IRQ_NONE;
682 
683 	err_status = hecc_read(priv, HECC_CANES);
684 	if (unlikely(err_status & HECC_CANES_FLAGS))
685 		ti_hecc_error(ndev, int_status, err_status);
686 
687 	if (unlikely(int_status & HECC_CANGIM_DEF_MASK)) {
688 		enum can_state rx_state, tx_state;
689 		u32 rec = hecc_read(priv, HECC_CANREC);
690 		u32 tec = hecc_read(priv, HECC_CANTEC);
691 
692 		if (int_status & HECC_CANGIF_WLIF) {
693 			handled |= HECC_CANGIF_WLIF;
694 			rx_state = rec >= tec ? CAN_STATE_ERROR_WARNING : 0;
695 			tx_state = rec <= tec ? CAN_STATE_ERROR_WARNING : 0;
696 			netdev_dbg(priv->ndev, "Error Warning interrupt\n");
697 			ti_hecc_change_state(ndev, rx_state, tx_state);
698 		}
699 
700 		if (int_status & HECC_CANGIF_EPIF) {
701 			handled |= HECC_CANGIF_EPIF;
702 			rx_state = rec >= tec ? CAN_STATE_ERROR_PASSIVE : 0;
703 			tx_state = rec <= tec ? CAN_STATE_ERROR_PASSIVE : 0;
704 			netdev_dbg(priv->ndev, "Error passive interrupt\n");
705 			ti_hecc_change_state(ndev, rx_state, tx_state);
706 		}
707 
708 		if (int_status & HECC_CANGIF_BOIF) {
709 			handled |= HECC_CANGIF_BOIF;
710 			rx_state = CAN_STATE_BUS_OFF;
711 			tx_state = CAN_STATE_BUS_OFF;
712 			netdev_dbg(priv->ndev, "Bus off interrupt\n");
713 
714 			/* Disable all interrupts */
715 			hecc_write(priv, HECC_CANGIM, 0);
716 			can_bus_off(ndev);
717 			ti_hecc_change_state(ndev, rx_state, tx_state);
718 		}
719 	} else if (unlikely(priv->can.state != CAN_STATE_ERROR_ACTIVE)) {
720 		enum can_state new_state, tx_state, rx_state;
721 		u32 rec = hecc_read(priv, HECC_CANREC);
722 		u32 tec = hecc_read(priv, HECC_CANTEC);
723 
724 		if (rec >= 128 || tec >= 128)
725 			new_state = CAN_STATE_ERROR_PASSIVE;
726 		else if (rec >= 96 || tec >= 96)
727 			new_state = CAN_STATE_ERROR_WARNING;
728 		else
729 			new_state = CAN_STATE_ERROR_ACTIVE;
730 
731 		if (new_state < priv->can.state) {
732 			rx_state = rec >= tec ? new_state : 0;
733 			tx_state = rec <= tec ? new_state : 0;
734 			ti_hecc_change_state(ndev, rx_state, tx_state);
735 		}
736 	}
737 
738 	if (int_status & HECC_CANGIF_GMIF) {
739 		while (priv->tx_tail - priv->tx_head > 0) {
740 			mbxno = get_tx_tail_mb(priv);
741 			mbx_mask = BIT(mbxno);
742 			if (!(mbx_mask & hecc_read(priv, HECC_CANTA)))
743 				break;
744 			hecc_write(priv, HECC_CANTA, mbx_mask);
745 			spin_lock_irqsave(&priv->mbx_lock, flags);
746 			hecc_clear_bit(priv, HECC_CANME, mbx_mask);
747 			spin_unlock_irqrestore(&priv->mbx_lock, flags);
748 			stamp = hecc_read_stamp(priv, mbxno);
749 			stats->tx_bytes +=
750 				can_rx_offload_get_echo_skb_queue_timestamp(&priv->offload,
751 									    mbxno, stamp, NULL);
752 			stats->tx_packets++;
753 			--priv->tx_tail;
754 		}
755 
756 		/* restart queue if wrap-up or if queue stalled on last pkt */
757 		if ((priv->tx_head == priv->tx_tail &&
758 		     ((priv->tx_head & HECC_TX_MASK) != HECC_TX_MASK)) ||
759 		    (((priv->tx_tail & HECC_TX_MASK) == HECC_TX_MASK) &&
760 		     ((priv->tx_head & HECC_TX_MASK) == HECC_TX_MASK)))
761 			netif_wake_queue(ndev);
762 
763 		/* offload RX mailboxes and let NAPI deliver them */
764 		while ((rx_pending = hecc_read(priv, HECC_CANRMP))) {
765 			can_rx_offload_irq_offload_timestamp(&priv->offload,
766 							     rx_pending);
767 		}
768 	}
769 
770 	/* clear all interrupt conditions - read back to avoid spurious ints */
771 	if (priv->use_hecc1int) {
772 		hecc_write(priv, HECC_CANGIF1, handled);
773 		int_status = hecc_read(priv, HECC_CANGIF1);
774 	} else {
775 		hecc_write(priv, HECC_CANGIF0, handled);
776 		int_status = hecc_read(priv, HECC_CANGIF0);
777 	}
778 
779 	can_rx_offload_irq_finish(&priv->offload);
780 
781 	return IRQ_HANDLED;
782 }
783 
ti_hecc_open(struct net_device * ndev)784 static int ti_hecc_open(struct net_device *ndev)
785 {
786 	struct ti_hecc_priv *priv = netdev_priv(ndev);
787 	int err;
788 
789 	err = request_irq(ndev->irq, ti_hecc_interrupt, IRQF_SHARED,
790 			  ndev->name, ndev);
791 	if (err) {
792 		netdev_err(ndev, "error requesting interrupt\n");
793 		return err;
794 	}
795 
796 	ti_hecc_transceiver_switch(priv, 1);
797 
798 	/* Open common can device */
799 	err = open_candev(ndev);
800 	if (err) {
801 		netdev_err(ndev, "open_candev() failed %d\n", err);
802 		ti_hecc_transceiver_switch(priv, 0);
803 		free_irq(ndev->irq, ndev);
804 		return err;
805 	}
806 
807 	ti_hecc_start(ndev);
808 	can_rx_offload_enable(&priv->offload);
809 	netif_start_queue(ndev);
810 
811 	return 0;
812 }
813 
ti_hecc_close(struct net_device * ndev)814 static int ti_hecc_close(struct net_device *ndev)
815 {
816 	struct ti_hecc_priv *priv = netdev_priv(ndev);
817 
818 	netif_stop_queue(ndev);
819 	can_rx_offload_disable(&priv->offload);
820 	ti_hecc_stop(ndev);
821 	free_irq(ndev->irq, ndev);
822 	close_candev(ndev);
823 	ti_hecc_transceiver_switch(priv, 0);
824 
825 	return 0;
826 }
827 
828 static const struct net_device_ops ti_hecc_netdev_ops = {
829 	.ndo_open		= ti_hecc_open,
830 	.ndo_stop		= ti_hecc_close,
831 	.ndo_start_xmit		= ti_hecc_xmit,
832 	.ndo_change_mtu		= can_change_mtu,
833 };
834 
835 static const struct ethtool_ops ti_hecc_ethtool_ops = {
836 	.get_ts_info = ethtool_op_get_ts_info,
837 };
838 
839 static const struct of_device_id ti_hecc_dt_ids[] = {
840 	{
841 		.compatible = "ti,am3517-hecc",
842 	},
843 	{ }
844 };
845 MODULE_DEVICE_TABLE(of, ti_hecc_dt_ids);
846 
ti_hecc_probe(struct platform_device * pdev)847 static int ti_hecc_probe(struct platform_device *pdev)
848 {
849 	struct net_device *ndev = (struct net_device *)0;
850 	struct ti_hecc_priv *priv;
851 	struct device_node *np = pdev->dev.of_node;
852 	struct regulator *reg_xceiver;
853 	int err = -ENODEV;
854 
855 	if (!IS_ENABLED(CONFIG_OF) || !np)
856 		return -EINVAL;
857 
858 	reg_xceiver = devm_regulator_get(&pdev->dev, "xceiver");
859 	if (PTR_ERR(reg_xceiver) == -EPROBE_DEFER)
860 		return -EPROBE_DEFER;
861 	else if (IS_ERR(reg_xceiver))
862 		reg_xceiver = NULL;
863 
864 	ndev = alloc_candev(sizeof(struct ti_hecc_priv), HECC_MAX_TX_MBOX);
865 	if (!ndev) {
866 		dev_err(&pdev->dev, "alloc_candev failed\n");
867 		return -ENOMEM;
868 	}
869 	priv = netdev_priv(ndev);
870 
871 	/* handle hecc memory */
872 	priv->base = devm_platform_ioremap_resource_byname(pdev, "hecc");
873 	if (IS_ERR(priv->base)) {
874 		dev_err(&pdev->dev, "hecc ioremap failed\n");
875 		err = PTR_ERR(priv->base);
876 		goto probe_exit_candev;
877 	}
878 
879 	/* handle hecc-ram memory */
880 	priv->hecc_ram = devm_platform_ioremap_resource_byname(pdev,
881 							       "hecc-ram");
882 	if (IS_ERR(priv->hecc_ram)) {
883 		dev_err(&pdev->dev, "hecc-ram ioremap failed\n");
884 		err = PTR_ERR(priv->hecc_ram);
885 		goto probe_exit_candev;
886 	}
887 
888 	/* handle mbx memory */
889 	priv->mbx = devm_platform_ioremap_resource_byname(pdev, "mbx");
890 	if (IS_ERR(priv->mbx)) {
891 		dev_err(&pdev->dev, "mbx ioremap failed\n");
892 		err = PTR_ERR(priv->mbx);
893 		goto probe_exit_candev;
894 	}
895 
896 	ndev->irq = platform_get_irq(pdev, 0);
897 	if (ndev->irq < 0) {
898 		err = ndev->irq;
899 		goto probe_exit_candev;
900 	}
901 
902 	priv->ndev = ndev;
903 	priv->reg_xceiver = reg_xceiver;
904 	priv->use_hecc1int = of_property_read_bool(np, "ti,use-hecc1int");
905 
906 	priv->can.bittiming_const = &ti_hecc_bittiming_const;
907 	priv->can.do_set_mode = ti_hecc_do_set_mode;
908 	priv->can.do_get_berr_counter = ti_hecc_get_berr_counter;
909 	priv->can.ctrlmode_supported = CAN_CTRLMODE_3_SAMPLES;
910 
911 	spin_lock_init(&priv->mbx_lock);
912 	ndev->flags |= IFF_ECHO;
913 	platform_set_drvdata(pdev, ndev);
914 	SET_NETDEV_DEV(ndev, &pdev->dev);
915 	ndev->netdev_ops = &ti_hecc_netdev_ops;
916 	ndev->ethtool_ops = &ti_hecc_ethtool_ops;
917 
918 	priv->clk = clk_get(&pdev->dev, "hecc_ck");
919 	if (IS_ERR(priv->clk)) {
920 		dev_err(&pdev->dev, "No clock available\n");
921 		err = PTR_ERR(priv->clk);
922 		priv->clk = NULL;
923 		goto probe_exit_candev;
924 	}
925 	priv->can.clock.freq = clk_get_rate(priv->clk);
926 
927 	err = clk_prepare_enable(priv->clk);
928 	if (err) {
929 		dev_err(&pdev->dev, "clk_prepare_enable() failed\n");
930 		goto probe_exit_release_clk;
931 	}
932 
933 	priv->offload.mailbox_read = ti_hecc_mailbox_read;
934 	priv->offload.mb_first = HECC_RX_FIRST_MBOX;
935 	priv->offload.mb_last = HECC_RX_LAST_MBOX;
936 	err = can_rx_offload_add_timestamp(ndev, &priv->offload);
937 	if (err) {
938 		dev_err(&pdev->dev, "can_rx_offload_add_timestamp() failed\n");
939 		goto probe_exit_disable_clk;
940 	}
941 
942 	err = register_candev(ndev);
943 	if (err) {
944 		dev_err(&pdev->dev, "register_candev() failed\n");
945 		goto probe_exit_offload;
946 	}
947 
948 	dev_info(&pdev->dev, "device registered (reg_base=%p, irq=%u)\n",
949 		 priv->base, (u32)ndev->irq);
950 
951 	return 0;
952 
953 probe_exit_offload:
954 	can_rx_offload_del(&priv->offload);
955 probe_exit_disable_clk:
956 	clk_disable_unprepare(priv->clk);
957 probe_exit_release_clk:
958 	clk_put(priv->clk);
959 probe_exit_candev:
960 	free_candev(ndev);
961 
962 	return err;
963 }
964 
ti_hecc_remove(struct platform_device * pdev)965 static void ti_hecc_remove(struct platform_device *pdev)
966 {
967 	struct net_device *ndev = platform_get_drvdata(pdev);
968 	struct ti_hecc_priv *priv = netdev_priv(ndev);
969 
970 	unregister_candev(ndev);
971 	clk_disable_unprepare(priv->clk);
972 	clk_put(priv->clk);
973 	can_rx_offload_del(&priv->offload);
974 	free_candev(ndev);
975 }
976 
977 #ifdef CONFIG_PM
ti_hecc_suspend(struct platform_device * pdev,pm_message_t state)978 static int ti_hecc_suspend(struct platform_device *pdev, pm_message_t state)
979 {
980 	struct net_device *dev = platform_get_drvdata(pdev);
981 	struct ti_hecc_priv *priv = netdev_priv(dev);
982 
983 	if (netif_running(dev)) {
984 		netif_stop_queue(dev);
985 		netif_device_detach(dev);
986 	}
987 
988 	hecc_set_bit(priv, HECC_CANMC, HECC_CANMC_PDR);
989 	priv->can.state = CAN_STATE_SLEEPING;
990 
991 	clk_disable_unprepare(priv->clk);
992 
993 	return 0;
994 }
995 
ti_hecc_resume(struct platform_device * pdev)996 static int ti_hecc_resume(struct platform_device *pdev)
997 {
998 	struct net_device *dev = platform_get_drvdata(pdev);
999 	struct ti_hecc_priv *priv = netdev_priv(dev);
1000 	int err;
1001 
1002 	err = clk_prepare_enable(priv->clk);
1003 	if (err)
1004 		return err;
1005 
1006 	hecc_clear_bit(priv, HECC_CANMC, HECC_CANMC_PDR);
1007 	priv->can.state = CAN_STATE_ERROR_ACTIVE;
1008 
1009 	if (netif_running(dev)) {
1010 		netif_device_attach(dev);
1011 		netif_start_queue(dev);
1012 	}
1013 
1014 	return 0;
1015 }
1016 #else
1017 #define ti_hecc_suspend NULL
1018 #define ti_hecc_resume NULL
1019 #endif
1020 
1021 /* TI HECC netdevice driver: platform driver structure */
1022 static struct platform_driver ti_hecc_driver = {
1023 	.driver = {
1024 		.name    = DRV_NAME,
1025 		.of_match_table = ti_hecc_dt_ids,
1026 	},
1027 	.probe = ti_hecc_probe,
1028 	.remove_new = ti_hecc_remove,
1029 	.suspend = ti_hecc_suspend,
1030 	.resume = ti_hecc_resume,
1031 };
1032 
1033 module_platform_driver(ti_hecc_driver);
1034 
1035 MODULE_AUTHOR("Anant Gole <anantgole@ti.com>");
1036 MODULE_LICENSE("GPL v2");
1037 MODULE_DESCRIPTION(DRV_DESC);
1038 MODULE_ALIAS("platform:" DRV_NAME);
1039