1// SPDX-License-Identifier: GPL-2.0-only
2// Copyright (C) 2014 Broadcom Corporation
3
4#include <linux/clk.h>
5#include <linux/delay.h>
6#include <linux/device.h>
7#include <linux/i2c.h>
8#include <linux/interrupt.h>
9#include <linux/io.h>
10#include <linux/kernel.h>
11#include <linux/module.h>
12#include <linux/platform_device.h>
13#include <linux/sched.h>
14#include <linux/slab.h>
15
16#define N_DATA_REGS					8
17
18/*
19 * PER_I2C/BSC count register mask depends on 1 byte/4 byte data register
20 * size. Cable modem and DSL SoCs with Peripheral i2c cores use 1 byte per
21 * data register whereas STB SoCs use 4 byte per data register transfer,
22 * account for this difference in total count per transaction and mask to
23 * use.
24 */
25#define BSC_CNT_REG1_MASK(nb)	(nb == 1 ? GENMASK(3, 0) : GENMASK(5, 0))
26#define BSC_CNT_REG1_SHIFT	0
27
28/* BSC CTL register field definitions */
29#define BSC_CTL_REG_DTF_MASK				0x00000003
30#define BSC_CTL_REG_SCL_SEL_MASK			0x00000030
31#define BSC_CTL_REG_SCL_SEL_SHIFT			4
32#define BSC_CTL_REG_INT_EN_MASK				0x00000040
33#define BSC_CTL_REG_INT_EN_SHIFT			6
34#define BSC_CTL_REG_DIV_CLK_MASK			0x00000080
35
36/* BSC_IIC_ENABLE r/w enable and interrupt field definitions */
37#define BSC_IIC_EN_RESTART_MASK				0x00000040
38#define BSC_IIC_EN_NOSTART_MASK				0x00000020
39#define BSC_IIC_EN_NOSTOP_MASK				0x00000010
40#define BSC_IIC_EN_NOACK_MASK				0x00000004
41#define BSC_IIC_EN_INTRP_MASK				0x00000002
42#define BSC_IIC_EN_ENABLE_MASK				0x00000001
43
44/* BSC_CTLHI control register field definitions */
45#define BSC_CTLHI_REG_INPUT_SWITCHING_LEVEL_MASK	0x00000080
46#define BSC_CTLHI_REG_DATAREG_SIZE_MASK			0x00000040
47#define BSC_CTLHI_REG_IGNORE_ACK_MASK			0x00000002
48#define BSC_CTLHI_REG_WAIT_DIS_MASK			0x00000001
49
50#define I2C_TIMEOUT					100 /* msecs */
51
52/* Condition mask used for non combined transfer */
53#define COND_RESTART		BSC_IIC_EN_RESTART_MASK
54#define COND_NOSTART		BSC_IIC_EN_NOSTART_MASK
55#define COND_NOSTOP		BSC_IIC_EN_NOSTOP_MASK
56#define COND_START_STOP		(COND_RESTART | COND_NOSTART | COND_NOSTOP)
57
58/* BSC data transfer direction */
59#define DTF_WR_MASK		0x00000000
60#define DTF_RD_MASK		0x00000001
61/* BSC data transfer direction combined format */
62#define DTF_RD_WR_MASK		0x00000002
63#define DTF_WR_RD_MASK		0x00000003
64
65#define INT_ENABLE		true
66#define INT_DISABLE		false
67
68/* BSC block register map structure to cache fields to be written */
69struct bsc_regs {
70	u32	chip_address;           /* slave address */
71	u32	data_in[N_DATA_REGS];   /* tx data buffer*/
72	u32	cnt_reg;		/* rx/tx data length */
73	u32	ctl_reg;		/* control register */
74	u32	iic_enable;		/* xfer enable and status */
75	u32	data_out[N_DATA_REGS];  /* rx data buffer */
76	u32	ctlhi_reg;		/* more control fields */
77	u32	scl_param;		/* reserved */
78};
79
80struct bsc_clk_param {
81	u32 hz;
82	u32 scl_mask;
83	u32 div_mask;
84};
85
86enum bsc_xfer_cmd {
87	CMD_WR,
88	CMD_RD,
89	CMD_WR_NOACK,
90	CMD_RD_NOACK,
91};
92
93static char const *cmd_string[] = {
94	[CMD_WR] = "WR",
95	[CMD_RD] = "RD",
96	[CMD_WR_NOACK] = "WR NOACK",
97	[CMD_RD_NOACK] = "RD NOACK",
98};
99
100enum bus_speeds {
101	SPD_375K,
102	SPD_390K,
103	SPD_187K,
104	SPD_200K,
105	SPD_93K,
106	SPD_97K,
107	SPD_46K,
108	SPD_50K
109};
110
111static const struct bsc_clk_param bsc_clk[] = {
112	[SPD_375K] = {
113		.hz = 375000,
114		.scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT,
115		.div_mask = 0
116	},
117	[SPD_390K] = {
118		.hz = 390000,
119		.scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT,
120		.div_mask = 0
121	},
122	[SPD_187K] = {
123		.hz = 187500,
124		.scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT,
125		.div_mask = 0
126	},
127	[SPD_200K] = {
128		.hz = 200000,
129		.scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT,
130		.div_mask = 0
131	},
132	[SPD_93K]  = {
133		.hz = 93750,
134		.scl_mask = SPD_375K << BSC_CTL_REG_SCL_SEL_SHIFT,
135		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
136	},
137	[SPD_97K]  = {
138		.hz = 97500,
139		.scl_mask = SPD_390K << BSC_CTL_REG_SCL_SEL_SHIFT,
140		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
141	},
142	[SPD_46K]  = {
143		.hz = 46875,
144		.scl_mask = SPD_187K << BSC_CTL_REG_SCL_SEL_SHIFT,
145		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
146	},
147	[SPD_50K]  = {
148		.hz = 50000,
149		.scl_mask = SPD_200K << BSC_CTL_REG_SCL_SEL_SHIFT,
150		.div_mask = BSC_CTL_REG_DIV_CLK_MASK
151	}
152};
153
154struct brcmstb_i2c_dev {
155	struct device *device;
156	void __iomem *base;
157	int irq;
158	struct bsc_regs *bsc_regmap;
159	struct i2c_adapter adapter;
160	struct completion done;
161	u32 clk_freq_hz;
162	int data_regsz;
163	bool atomic;
164};
165
166/* register accessors for both be and le cpu arch */
167#ifdef CONFIG_CPU_BIG_ENDIAN
168#define __bsc_readl(_reg) ioread32be(_reg)
169#define __bsc_writel(_val, _reg) iowrite32be(_val, _reg)
170#else
171#define __bsc_readl(_reg) ioread32(_reg)
172#define __bsc_writel(_val, _reg) iowrite32(_val, _reg)
173#endif
174
175#define bsc_readl(_dev, _reg)						\
176	__bsc_readl(_dev->base + offsetof(struct bsc_regs, _reg))
177
178#define bsc_writel(_dev, _val, _reg)					\
179	__bsc_writel(_val, _dev->base + offsetof(struct bsc_regs, _reg))
180
181static inline int brcmstb_i2c_get_xfersz(struct brcmstb_i2c_dev *dev)
182{
183	return (N_DATA_REGS * dev->data_regsz);
184}
185
186static inline int brcmstb_i2c_get_data_regsz(struct brcmstb_i2c_dev *dev)
187{
188	return dev->data_regsz;
189}
190
191static void brcmstb_i2c_enable_disable_irq(struct brcmstb_i2c_dev *dev,
192					   bool int_en)
193{
194
195	if (int_en)
196		/* Enable BSC  CTL interrupt line */
197		dev->bsc_regmap->ctl_reg |= BSC_CTL_REG_INT_EN_MASK;
198	else
199		/* Disable BSC CTL interrupt line */
200		dev->bsc_regmap->ctl_reg &= ~BSC_CTL_REG_INT_EN_MASK;
201
202	barrier();
203	bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg);
204}
205
206static irqreturn_t brcmstb_i2c_isr(int irq, void *devid)
207{
208	struct brcmstb_i2c_dev *dev = devid;
209	u32 status_bsc_ctl = bsc_readl(dev, ctl_reg);
210	u32 status_iic_intrp = bsc_readl(dev, iic_enable);
211
212	dev_dbg(dev->device, "isr CTL_REG %x IIC_EN %x\n",
213		status_bsc_ctl, status_iic_intrp);
214
215	if (!(status_bsc_ctl & BSC_CTL_REG_INT_EN_MASK))
216		return IRQ_NONE;
217
218	brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
219	complete(&dev->done);
220
221	dev_dbg(dev->device, "isr handled");
222	return IRQ_HANDLED;
223}
224
225/* Wait for device to be ready */
226static int brcmstb_i2c_wait_if_busy(struct brcmstb_i2c_dev *dev)
227{
228	unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT);
229
230	while ((bsc_readl(dev, iic_enable) & BSC_IIC_EN_INTRP_MASK)) {
231		if (time_after(jiffies, timeout))
232			return -ETIMEDOUT;
233		cpu_relax();
234	}
235	return 0;
236}
237
238/* i2c xfer completion function, handles both irq and polling mode */
239static int brcmstb_i2c_wait_for_completion(struct brcmstb_i2c_dev *dev)
240{
241	int ret = 0;
242	unsigned long timeout = msecs_to_jiffies(I2C_TIMEOUT);
243
244	if (dev->irq >= 0 && !dev->atomic) {
245		if (!wait_for_completion_timeout(&dev->done, timeout))
246			ret = -ETIMEDOUT;
247	} else {
248		/* we are in polling mode */
249		u32 bsc_intrp;
250		unsigned long time_left = jiffies + timeout;
251
252		do {
253			bsc_intrp = bsc_readl(dev, iic_enable) &
254				BSC_IIC_EN_INTRP_MASK;
255			if (time_after(jiffies, time_left)) {
256				ret = -ETIMEDOUT;
257				break;
258			}
259			cpu_relax();
260		} while (!bsc_intrp);
261	}
262
263	if (dev->irq < 0 || ret == -ETIMEDOUT)
264		brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
265
266	return ret;
267}
268
269/* Set xfer START/STOP conditions for subsequent transfer */
270static void brcmstb_set_i2c_start_stop(struct brcmstb_i2c_dev *dev,
271				       u32 cond_flag)
272{
273	u32 regval = dev->bsc_regmap->iic_enable;
274
275	dev->bsc_regmap->iic_enable = (regval & ~COND_START_STOP) | cond_flag;
276}
277
278/* Send I2C request check completion */
279static int brcmstb_send_i2c_cmd(struct brcmstb_i2c_dev *dev,
280				enum bsc_xfer_cmd cmd)
281{
282	int rc = 0;
283	struct bsc_regs *pi2creg = dev->bsc_regmap;
284
285	/* Make sure the hardware is ready */
286	rc = brcmstb_i2c_wait_if_busy(dev);
287	if (rc < 0)
288		return rc;
289
290	/* only if we are in interrupt mode */
291	if (dev->irq >= 0 && !dev->atomic)
292		reinit_completion(&dev->done);
293
294	/* enable BSC CTL interrupt line */
295	brcmstb_i2c_enable_disable_irq(dev, INT_ENABLE);
296
297	/* initiate transfer by setting iic_enable */
298	pi2creg->iic_enable |= BSC_IIC_EN_ENABLE_MASK;
299	bsc_writel(dev, pi2creg->iic_enable, iic_enable);
300
301	/* Wait for transaction to finish or timeout */
302	rc = brcmstb_i2c_wait_for_completion(dev);
303	if (rc) {
304		dev_dbg(dev->device, "intr timeout for cmd %s\n",
305			cmd_string[cmd]);
306		goto cmd_out;
307	}
308
309	if ((cmd == CMD_RD || cmd == CMD_WR) &&
310	    bsc_readl(dev, iic_enable) & BSC_IIC_EN_NOACK_MASK) {
311		rc = -EREMOTEIO;
312		dev_dbg(dev->device, "controller received NOACK intr for %s\n",
313			cmd_string[cmd]);
314	}
315
316cmd_out:
317	bsc_writel(dev, 0, cnt_reg);
318	bsc_writel(dev, 0, iic_enable);
319
320	return rc;
321}
322
323/* Actual data transfer through the BSC master */
324static int brcmstb_i2c_xfer_bsc_data(struct brcmstb_i2c_dev *dev,
325				     u8 *buf, unsigned int len,
326				     struct i2c_msg *pmsg)
327{
328	int cnt, byte, i, rc;
329	enum bsc_xfer_cmd cmd;
330	u32 ctl_reg;
331	struct bsc_regs *pi2creg = dev->bsc_regmap;
332	int no_ack = pmsg->flags & I2C_M_IGNORE_NAK;
333	int data_regsz = brcmstb_i2c_get_data_regsz(dev);
334
335	/* see if the transaction needs to check NACK conditions */
336	if (no_ack) {
337		cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD_NOACK
338			: CMD_WR_NOACK;
339		pi2creg->ctlhi_reg |= BSC_CTLHI_REG_IGNORE_ACK_MASK;
340	} else {
341		cmd = (pmsg->flags & I2C_M_RD) ? CMD_RD : CMD_WR;
342		pi2creg->ctlhi_reg &= ~BSC_CTLHI_REG_IGNORE_ACK_MASK;
343	}
344	bsc_writel(dev, pi2creg->ctlhi_reg, ctlhi_reg);
345
346	/* set data transfer direction */
347	ctl_reg = pi2creg->ctl_reg & ~BSC_CTL_REG_DTF_MASK;
348	if (cmd == CMD_WR || cmd == CMD_WR_NOACK)
349		pi2creg->ctl_reg = ctl_reg | DTF_WR_MASK;
350	else
351		pi2creg->ctl_reg = ctl_reg | DTF_RD_MASK;
352
353	/* set the read/write length */
354	bsc_writel(dev, BSC_CNT_REG1_MASK(data_regsz) &
355		   (len << BSC_CNT_REG1_SHIFT), cnt_reg);
356
357	/* Write data into data_in register */
358
359	if (cmd == CMD_WR || cmd == CMD_WR_NOACK) {
360		for (cnt = 0, i = 0; cnt < len; cnt += data_regsz, i++) {
361			u32 word = 0;
362
363			for (byte = 0; byte < data_regsz; byte++) {
364				word >>= BITS_PER_BYTE;
365				if ((cnt + byte) < len)
366					word |= buf[cnt + byte] <<
367					(BITS_PER_BYTE * (data_regsz - 1));
368			}
369			bsc_writel(dev, word, data_in[i]);
370		}
371	}
372
373	/* Initiate xfer, the function will return on completion */
374	rc = brcmstb_send_i2c_cmd(dev, cmd);
375
376	if (rc != 0) {
377		dev_dbg(dev->device, "%s failure", cmd_string[cmd]);
378		return rc;
379	}
380
381	/* Read data from data_out register */
382	if (cmd == CMD_RD || cmd == CMD_RD_NOACK) {
383		for (cnt = 0, i = 0; cnt < len; cnt += data_regsz, i++) {
384			u32 data = bsc_readl(dev, data_out[i]);
385
386			for (byte = 0; byte < data_regsz &&
387				     (byte + cnt) < len; byte++) {
388				buf[cnt + byte] = data & 0xff;
389				data >>= BITS_PER_BYTE;
390			}
391		}
392	}
393
394	return 0;
395}
396
397/* Write a single byte of data to the i2c bus */
398static int brcmstb_i2c_write_data_byte(struct brcmstb_i2c_dev *dev,
399				       u8 *buf, unsigned int nak_expected)
400{
401	enum bsc_xfer_cmd cmd = nak_expected ? CMD_WR : CMD_WR_NOACK;
402
403	bsc_writel(dev, 1, cnt_reg);
404	bsc_writel(dev, *buf, data_in);
405
406	return brcmstb_send_i2c_cmd(dev, cmd);
407}
408
409/* Send i2c address */
410static int brcmstb_i2c_do_addr(struct brcmstb_i2c_dev *dev,
411			       struct i2c_msg *msg)
412{
413	unsigned char addr;
414
415	if (msg->flags & I2C_M_TEN) {
416		/* First byte is 11110XX0 where XX is upper 2 bits */
417		addr = 0xF0 | ((msg->addr & 0x300) >> 7);
418		bsc_writel(dev, addr, chip_address);
419
420		/* Second byte is the remaining 8 bits */
421		addr = msg->addr & 0xFF;
422		if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0)
423			return -EREMOTEIO;
424
425		if (msg->flags & I2C_M_RD) {
426			/* For read, send restart without stop condition */
427			brcmstb_set_i2c_start_stop(dev, COND_RESTART
428						   | COND_NOSTOP);
429			/* Then re-send the first byte with the read bit set */
430			addr = 0xF0 | ((msg->addr & 0x300) >> 7) | 0x01;
431			if (brcmstb_i2c_write_data_byte(dev, &addr, 0) < 0)
432				return -EREMOTEIO;
433
434		}
435	} else {
436		addr = i2c_8bit_addr_from_msg(msg);
437
438		bsc_writel(dev, addr, chip_address);
439	}
440
441	return 0;
442}
443
444/* Master transfer function */
445static int brcmstb_i2c_xfer(struct i2c_adapter *adapter,
446			    struct i2c_msg msgs[], int num)
447{
448	struct brcmstb_i2c_dev *dev = i2c_get_adapdata(adapter);
449	struct i2c_msg *pmsg;
450	int rc = 0;
451	int i;
452	int bytes_to_xfer;
453	u8 *tmp_buf;
454	int len = 0;
455	int xfersz = brcmstb_i2c_get_xfersz(dev);
456	u32 cond, cond_per_msg;
457
458	/* Loop through all messages */
459	for (i = 0; i < num; i++) {
460		pmsg = &msgs[i];
461		len = pmsg->len;
462		tmp_buf = pmsg->buf;
463
464		dev_dbg(dev->device,
465			"msg# %d/%d flg %x buf %x len %d\n", i,
466			num - 1, pmsg->flags,
467			pmsg->buf ? pmsg->buf[0] : '0', pmsg->len);
468
469		if (i < (num - 1) && (msgs[i + 1].flags & I2C_M_NOSTART))
470			cond = ~COND_START_STOP;
471		else
472			cond = COND_RESTART | COND_NOSTOP;
473
474		brcmstb_set_i2c_start_stop(dev, cond);
475
476		/* Send slave address */
477		if (!(pmsg->flags & I2C_M_NOSTART)) {
478			rc = brcmstb_i2c_do_addr(dev, pmsg);
479			if (rc < 0) {
480				dev_dbg(dev->device,
481					"NACK for addr %2.2x msg#%d rc = %d\n",
482					pmsg->addr, i, rc);
483				goto out;
484			}
485		}
486
487		cond_per_msg = cond;
488
489		/* Perform data transfer */
490		while (len) {
491			bytes_to_xfer = min(len, xfersz);
492
493			if (len <= xfersz) {
494				if (i == (num - 1))
495					cond_per_msg = cond_per_msg &
496						~(COND_RESTART | COND_NOSTOP);
497				else
498					cond_per_msg = cond;
499			} else {
500				cond_per_msg = (cond_per_msg & ~COND_RESTART) |
501					COND_NOSTOP;
502			}
503
504			brcmstb_set_i2c_start_stop(dev, cond_per_msg);
505
506			rc = brcmstb_i2c_xfer_bsc_data(dev, tmp_buf,
507						       bytes_to_xfer, pmsg);
508			if (rc < 0)
509				goto out;
510
511			len -=  bytes_to_xfer;
512			tmp_buf += bytes_to_xfer;
513
514			cond_per_msg = COND_NOSTART | COND_NOSTOP;
515		}
516	}
517
518	rc = num;
519out:
520	return rc;
521
522}
523
524static int brcmstb_i2c_xfer_atomic(struct i2c_adapter *adapter,
525				   struct i2c_msg msgs[], int num)
526{
527	struct brcmstb_i2c_dev *dev = i2c_get_adapdata(adapter);
528	int ret;
529
530	if (dev->irq >= 0)
531		disable_irq(dev->irq);
532	dev->atomic = true;
533	ret = brcmstb_i2c_xfer(adapter, msgs, num);
534	dev->atomic = false;
535	if (dev->irq >= 0)
536		enable_irq(dev->irq);
537
538	return ret;
539}
540
541static u32 brcmstb_i2c_functionality(struct i2c_adapter *adap)
542{
543	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR
544		| I2C_FUNC_NOSTART | I2C_FUNC_PROTOCOL_MANGLING;
545}
546
547static const struct i2c_algorithm brcmstb_i2c_algo = {
548	.master_xfer = brcmstb_i2c_xfer,
549	.master_xfer_atomic = brcmstb_i2c_xfer_atomic,
550	.functionality = brcmstb_i2c_functionality,
551};
552
553static void brcmstb_i2c_set_bus_speed(struct brcmstb_i2c_dev *dev)
554{
555	int i = 0, num_speeds = ARRAY_SIZE(bsc_clk);
556	u32 clk_freq_hz = dev->clk_freq_hz;
557
558	for (i = 0; i < num_speeds; i++) {
559		if (bsc_clk[i].hz == clk_freq_hz) {
560			dev->bsc_regmap->ctl_reg &= ~(BSC_CTL_REG_SCL_SEL_MASK
561						| BSC_CTL_REG_DIV_CLK_MASK);
562			dev->bsc_regmap->ctl_reg |= (bsc_clk[i].scl_mask |
563						     bsc_clk[i].div_mask);
564			bsc_writel(dev, dev->bsc_regmap->ctl_reg, ctl_reg);
565			break;
566		}
567	}
568
569	/* in case we did not get find a valid speed */
570	if (i == num_speeds) {
571		i = (bsc_readl(dev, ctl_reg) & BSC_CTL_REG_SCL_SEL_MASK) >>
572			BSC_CTL_REG_SCL_SEL_SHIFT;
573		dev_warn(dev->device, "leaving current clock-frequency @ %dHz\n",
574			bsc_clk[i].hz);
575	}
576}
577
578static void brcmstb_i2c_set_bsc_reg_defaults(struct brcmstb_i2c_dev *dev)
579{
580	if (brcmstb_i2c_get_data_regsz(dev) == sizeof(u32))
581		/* set 4 byte data in/out xfers  */
582		dev->bsc_regmap->ctlhi_reg = BSC_CTLHI_REG_DATAREG_SIZE_MASK;
583	else
584		dev->bsc_regmap->ctlhi_reg &= ~BSC_CTLHI_REG_DATAREG_SIZE_MASK;
585
586	bsc_writel(dev, dev->bsc_regmap->ctlhi_reg, ctlhi_reg);
587	/* set bus speed */
588	brcmstb_i2c_set_bus_speed(dev);
589}
590
591#define AUTOI2C_CTRL0		0x26c
592#define AUTOI2C_CTRL0_RELEASE_BSC	BIT(1)
593
594static int bcm2711_release_bsc(struct brcmstb_i2c_dev *dev)
595{
596	struct platform_device *pdev = to_platform_device(dev->device);
597	void __iomem *autoi2c;
598
599	/* Map hardware registers */
600	autoi2c = devm_platform_ioremap_resource_byname(pdev, "auto-i2c");
601	if (IS_ERR(autoi2c))
602		return PTR_ERR(autoi2c);
603
604	writel(AUTOI2C_CTRL0_RELEASE_BSC, autoi2c + AUTOI2C_CTRL0);
605	devm_iounmap(&pdev->dev, autoi2c);
606
607	/* We need to reset the controller after the release */
608	dev->bsc_regmap->iic_enable = 0;
609	bsc_writel(dev, dev->bsc_regmap->iic_enable, iic_enable);
610
611	return 0;
612}
613
614static int brcmstb_i2c_probe(struct platform_device *pdev)
615{
616	struct brcmstb_i2c_dev *dev;
617	struct i2c_adapter *adap;
618	const char *int_name;
619	int rc;
620
621	/* Allocate memory for private data structure */
622	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
623	if (!dev)
624		return -ENOMEM;
625
626	dev->bsc_regmap = devm_kzalloc(&pdev->dev, sizeof(*dev->bsc_regmap), GFP_KERNEL);
627	if (!dev->bsc_regmap)
628		return -ENOMEM;
629
630	platform_set_drvdata(pdev, dev);
631	dev->device = &pdev->dev;
632	init_completion(&dev->done);
633
634	/* Map hardware registers */
635	dev->base = devm_platform_ioremap_resource(pdev, 0);
636	if (IS_ERR(dev->base))
637		return PTR_ERR(dev->base);
638
639	if (of_device_is_compatible(dev->device->of_node,
640				    "brcm,bcm2711-hdmi-i2c")) {
641		rc = bcm2711_release_bsc(dev);
642		if (rc)
643			return rc;
644	}
645
646	rc = of_property_read_string(dev->device->of_node, "interrupt-names",
647				     &int_name);
648	if (rc < 0)
649		int_name = NULL;
650
651	/* Get the interrupt number */
652	dev->irq = platform_get_irq_optional(pdev, 0);
653
654	/* disable the bsc interrupt line */
655	brcmstb_i2c_enable_disable_irq(dev, INT_DISABLE);
656
657	/* register the ISR handler */
658	if (dev->irq >= 0) {
659		rc = devm_request_irq(&pdev->dev, dev->irq, brcmstb_i2c_isr,
660				      IRQF_SHARED,
661				      int_name ? int_name : pdev->name,
662				      dev);
663
664		if (rc) {
665			dev_dbg(dev->device, "falling back to polling mode");
666			dev->irq = -1;
667		}
668	}
669
670	if (of_property_read_u32(dev->device->of_node,
671				 "clock-frequency", &dev->clk_freq_hz)) {
672		dev_warn(dev->device, "setting clock-frequency@%dHz\n",
673			 bsc_clk[0].hz);
674		dev->clk_freq_hz = bsc_clk[0].hz;
675	}
676
677	/* set the data in/out register size for compatible SoCs */
678	if (of_device_is_compatible(dev->device->of_node,
679				    "brcm,brcmper-i2c"))
680		dev->data_regsz = sizeof(u8);
681	else
682		dev->data_regsz = sizeof(u32);
683
684	brcmstb_i2c_set_bsc_reg_defaults(dev);
685
686	/* Add the i2c adapter */
687	adap = &dev->adapter;
688	i2c_set_adapdata(adap, dev);
689	adap->owner = THIS_MODULE;
690	strscpy(adap->name, dev_name(&pdev->dev), sizeof(adap->name));
691	adap->algo = &brcmstb_i2c_algo;
692	adap->dev.parent = &pdev->dev;
693	adap->dev.of_node = pdev->dev.of_node;
694	rc = i2c_add_adapter(adap);
695	if (rc)
696		return rc;
697
698	dev_info(dev->device, "%s@%dhz registered in %s mode\n",
699		 int_name ? int_name : " ", dev->clk_freq_hz,
700		 (dev->irq >= 0) ? "interrupt" : "polling");
701
702	return 0;
703}
704
705static void brcmstb_i2c_remove(struct platform_device *pdev)
706{
707	struct brcmstb_i2c_dev *dev = platform_get_drvdata(pdev);
708
709	i2c_del_adapter(&dev->adapter);
710}
711
712static int brcmstb_i2c_suspend(struct device *dev)
713{
714	struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev);
715
716	i2c_mark_adapter_suspended(&i2c_dev->adapter);
717	return 0;
718}
719
720static int brcmstb_i2c_resume(struct device *dev)
721{
722	struct brcmstb_i2c_dev *i2c_dev = dev_get_drvdata(dev);
723
724	brcmstb_i2c_set_bsc_reg_defaults(i2c_dev);
725	i2c_mark_adapter_resumed(&i2c_dev->adapter);
726
727	return 0;
728}
729
730static DEFINE_SIMPLE_DEV_PM_OPS(brcmstb_i2c_pm, brcmstb_i2c_suspend,
731				brcmstb_i2c_resume);
732
733static const struct of_device_id brcmstb_i2c_of_match[] = {
734	{.compatible = "brcm,brcmstb-i2c"},
735	{.compatible = "brcm,brcmper-i2c"},
736	{.compatible = "brcm,bcm2711-hdmi-i2c"},
737	{},
738};
739MODULE_DEVICE_TABLE(of, brcmstb_i2c_of_match);
740
741static struct platform_driver brcmstb_i2c_driver = {
742	.driver = {
743		   .name = "brcmstb-i2c",
744		   .of_match_table = brcmstb_i2c_of_match,
745		   .pm = pm_sleep_ptr(&brcmstb_i2c_pm),
746		   },
747	.probe = brcmstb_i2c_probe,
748	.remove_new = brcmstb_i2c_remove,
749};
750module_platform_driver(brcmstb_i2c_driver);
751
752MODULE_AUTHOR("Kamal Dasu <kdasu@broadcom.com>");
753MODULE_DESCRIPTION("Broadcom Settop I2C Driver");
754MODULE_LICENSE("GPL v2");
755