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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * This is a combined i2c adapter and algorithm driver for the
  4 * MPC107/Tsi107 PowerPC northbridge and processors that include
  5 * the same I2C unit (8240, 8245, 85xx).
  6 *
  7 * Copyright (C) 2003-2004 Humboldt Solutions Ltd, adrian@humboldt.co.uk
  8 * Copyright (C) 2021 Allied Telesis Labs
  9 */
 10
 11#include <linux/kernel.h>
 12#include <linux/module.h>
 13#include <linux/sched/signal.h>
 14#include <linux/of.h>
 15#include <linux/of_address.h>
 16#include <linux/of_irq.h>
 17#include <linux/platform_device.h>
 18#include <linux/property.h>
 19#include <linux/slab.h>
 20
 21#include <linux/clk.h>
 22#include <linux/io.h>
 23#include <linux/iopoll.h>
 24#include <linux/fsl_devices.h>
 25#include <linux/i2c.h>
 26#include <linux/interrupt.h>
 27#include <linux/delay.h>
 28
 29#include <asm/mpc52xx.h>
 30#include <asm/mpc85xx.h>
 31#include <sysdev/fsl_soc.h>
 32
 
 
 33#define MPC_I2C_CLOCK_LEGACY   0
 34#define MPC_I2C_CLOCK_PRESERVE (~0U)
 35
 36#define MPC_I2C_FDR   0x04
 37#define MPC_I2C_CR    0x08
 38#define MPC_I2C_SR    0x0c
 39#define MPC_I2C_DR    0x10
 40#define MPC_I2C_DFSRR 0x14
 41
 42#define CCR_MEN  0x80
 43#define CCR_MIEN 0x40
 44#define CCR_MSTA 0x20
 45#define CCR_MTX  0x10
 46#define CCR_TXAK 0x08
 47#define CCR_RSTA 0x04
 48#define CCR_RSVD 0x02
 49
 50#define CSR_MCF  0x80
 51#define CSR_MAAS 0x40
 52#define CSR_MBB  0x20
 53#define CSR_MAL  0x10
 54#define CSR_SRW  0x04
 55#define CSR_MIF  0x02
 56#define CSR_RXAK 0x01
 57
 58enum mpc_i2c_action {
 59	MPC_I2C_ACTION_START = 1,
 60	MPC_I2C_ACTION_RESTART,
 61	MPC_I2C_ACTION_READ_BEGIN,
 62	MPC_I2C_ACTION_READ_BYTE,
 63	MPC_I2C_ACTION_WRITE,
 64	MPC_I2C_ACTION_STOP,
 65
 66	__MPC_I2C_ACTION_CNT
 67};
 68
 69static const char * const action_str[] = {
 70	"invalid",
 71	"start",
 72	"restart",
 73	"read begin",
 74	"read",
 75	"write",
 76	"stop",
 77};
 78
 79static_assert(ARRAY_SIZE(action_str) == __MPC_I2C_ACTION_CNT);
 80
 81struct mpc_i2c {
 82	struct device *dev;
 83	void __iomem *base;
 84	u32 interrupt;
 85	wait_queue_head_t waitq;
 86	spinlock_t lock;
 87	struct i2c_adapter adap;
 88	int irq;
 89	u32 real_clk;
 90	u8 fdr, dfsrr;
 
 91	u32 cntl_bits;
 92	enum mpc_i2c_action action;
 93	struct i2c_msg *msgs;
 94	int num_msgs;
 95	int curr_msg;
 96	u32 byte_posn;
 97	u32 block;
 98	int rc;
 99	int expect_rxack;
100	bool has_errata_A004447;
101};
102
103struct mpc_i2c_divider {
104	u16 divider;
105	u16 fdr;	/* including dfsrr */
106};
107
108struct mpc_i2c_data {
109	void (*setup)(struct device_node *node, struct mpc_i2c *i2c, u32 clock);
110};
111
112static inline void writeccr(struct mpc_i2c *i2c, u32 x)
113{
114	writeb(x, i2c->base + MPC_I2C_CR);
115}
116
117/* Sometimes 9th clock pulse isn't generated, and target doesn't release
118 * the bus, because it wants to send ACK.
119 * Following sequence of enabling/disabling and sending start/stop generates
120 * the 9 pulses, each with a START then ending with STOP, so it's all OK.
121 */
122static void mpc_i2c_fixup(struct mpc_i2c *i2c)
123{
124	int k;
125	unsigned long flags;
126
127	for (k = 9; k; k--) {
128		writeccr(i2c, 0);
129		writeb(0, i2c->base + MPC_I2C_SR); /* clear any status bits */
130		writeccr(i2c, CCR_MEN | CCR_MSTA); /* START */
131		readb(i2c->base + MPC_I2C_DR); /* init xfer */
132		udelay(15); /* let it hit the bus */
133		local_irq_save(flags); /* should not be delayed further */
134		writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSTA); /* delay SDA */
135		readb(i2c->base + MPC_I2C_DR);
136		if (k != 1)
137			udelay(5);
138		local_irq_restore(flags);
139	}
140	writeccr(i2c, CCR_MEN); /* Initiate STOP */
141	readb(i2c->base + MPC_I2C_DR);
142	udelay(15); /* Let STOP propagate */
143	writeccr(i2c, 0);
144}
145
146static int i2c_mpc_wait_sr(struct mpc_i2c *i2c, int mask)
147{
148	void __iomem *addr = i2c->base + MPC_I2C_SR;
149	u8 val;
150
151	return readb_poll_timeout(addr, val, val & mask, 0, 100);
152}
153
154/*
155 * Workaround for Erratum A004447. From the P2040CE Rev Q
156 *
157 * 1.  Set up the frequency divider and sampling rate.
158 * 2.  I2CCR - a0h
159 * 3.  Poll for I2CSR[MBB] to get set.
160 * 4.  If I2CSR[MAL] is set (an indication that SDA is stuck low), then go to
161 *     step 5. If MAL is not set, then go to step 13.
162 * 5.  I2CCR - 00h
163 * 6.  I2CCR - 22h
164 * 7.  I2CCR - a2h
165 * 8.  Poll for I2CSR[MBB] to get set.
166 * 9.  Issue read to I2CDR.
167 * 10. Poll for I2CSR[MIF] to be set.
168 * 11. I2CCR - 82h
169 * 12. Workaround complete. Skip the next steps.
170 * 13. Issue read to I2CDR.
171 * 14. Poll for I2CSR[MIF] to be set.
172 * 15. I2CCR - 80h
173 */
174static void mpc_i2c_fixup_A004447(struct mpc_i2c *i2c)
175{
176	int ret;
177	u32 val;
178
179	writeccr(i2c, CCR_MEN | CCR_MSTA);
180	ret = i2c_mpc_wait_sr(i2c, CSR_MBB);
181	if (ret) {
182		dev_err(i2c->dev, "timeout waiting for CSR_MBB\n");
183		return;
184	}
185
186	val = readb(i2c->base + MPC_I2C_SR);
187
188	if (val & CSR_MAL) {
189		writeccr(i2c, 0x00);
190		writeccr(i2c, CCR_MSTA | CCR_RSVD);
191		writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSVD);
192		ret = i2c_mpc_wait_sr(i2c, CSR_MBB);
193		if (ret) {
194			dev_err(i2c->dev, "timeout waiting for CSR_MBB\n");
195			return;
196		}
197		val = readb(i2c->base + MPC_I2C_DR);
198		ret = i2c_mpc_wait_sr(i2c, CSR_MIF);
199		if (ret) {
200			dev_err(i2c->dev, "timeout waiting for CSR_MIF\n");
201			return;
202		}
203		writeccr(i2c, CCR_MEN | CCR_RSVD);
204	} else {
205		val = readb(i2c->base + MPC_I2C_DR);
206		ret = i2c_mpc_wait_sr(i2c, CSR_MIF);
207		if (ret) {
208			dev_err(i2c->dev, "timeout waiting for CSR_MIF\n");
209			return;
210		}
211		writeccr(i2c, CCR_MEN);
212	}
213}
214
215#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
216static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
217	{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
218	{28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
219	{36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28},
220	{52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a},
221	{68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09},
222	{96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81},
223	{128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30},
224	{176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32},
225	{240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10},
226	{320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a},
227	{448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14},
228	{640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17},
229	{1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d},
230	{1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c},
231	{2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f},
232	{4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e},
233	{7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c},
234	{10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f}
235};
236
237static int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
238					  u32 *real_clk)
239{
240	struct fwnode_handle *fwnode = of_fwnode_handle(node);
241	const struct mpc_i2c_divider *div = NULL;
242	unsigned int pvr = mfspr(SPRN_PVR);
243	u32 divider;
244	int i;
245
246	if (clock == MPC_I2C_CLOCK_LEGACY) {
247		/* see below - default fdr = 0x3f -> div = 2048 */
248		*real_clk = mpc5xxx_fwnode_get_bus_frequency(fwnode) / 2048;
249		return -EINVAL;
250	}
251
252	/* Determine divider value */
253	divider = mpc5xxx_fwnode_get_bus_frequency(fwnode) / clock;
254
255	/*
256	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
257	 * is equal to or lower than the requested speed.
258	 */
259	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) {
260		div = &mpc_i2c_dividers_52xx[i];
261		/* Old MPC5200 rev A CPUs do not support the high bits */
262		if (div->fdr & 0xc0 && pvr == 0x80822011)
263			continue;
264		if (div->divider >= divider)
265			break;
266	}
267
268	*real_clk = mpc5xxx_fwnode_get_bus_frequency(fwnode) / div->divider;
269	return (int)div->fdr;
270}
271
272static void mpc_i2c_setup_52xx(struct device_node *node,
273					 struct mpc_i2c *i2c,
274					 u32 clock)
275{
276	int ret, fdr;
277
278	if (clock == MPC_I2C_CLOCK_PRESERVE) {
279		dev_dbg(i2c->dev, "using fdr %d\n",
280			readb(i2c->base + MPC_I2C_FDR));
281		return;
282	}
283
284	ret = mpc_i2c_get_fdr_52xx(node, clock, &i2c->real_clk);
285	fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
286
287	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
288
289	if (ret >= 0)
290		dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk,
291			 fdr);
292}
293#else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
294static void mpc_i2c_setup_52xx(struct device_node *node,
295					 struct mpc_i2c *i2c,
296					 u32 clock)
297{
298}
299#endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
300
301#ifdef CONFIG_PPC_MPC512x
302static void mpc_i2c_setup_512x(struct device_node *node,
303					 struct mpc_i2c *i2c,
304					 u32 clock)
305{
 
306	void __iomem *ctrl;
 
307	u32 idx;
308
309	/* Enable I2C interrupts for mpc5121 */
310	struct device_node *node_ctrl __free(device_node) =
311		of_find_compatible_node(NULL, NULL, "fsl,mpc5121-i2c-ctrl");
312	if (node_ctrl) {
313		ctrl = of_iomap(node_ctrl, 0);
314		if (ctrl) {
315			u64 addr;
316			/* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */
317			of_property_read_reg(node, 0, &addr, NULL);
318			idx = (addr & 0xff) / 0x20;
319			setbits32(ctrl, 1 << (24 + idx * 2));
320			iounmap(ctrl);
321		}
 
322	}
323
324	/* The clock setup for the 52xx works also fine for the 512x */
325	mpc_i2c_setup_52xx(node, i2c, clock);
326}
327#else /* CONFIG_PPC_MPC512x */
328static void mpc_i2c_setup_512x(struct device_node *node,
329					 struct mpc_i2c *i2c,
330					 u32 clock)
331{
332}
333#endif /* CONFIG_PPC_MPC512x */
334
335#ifdef CONFIG_FSL_SOC
336static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
337	{160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123},
338	{288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102},
339	{416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127},
340	{544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105},
341	{672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106},
342	{800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107},
343	{1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07},
344	{1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a},
345	{1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b},
346	{2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e},
347	{3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133},
348	{4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136},
349	{7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115},
350	{12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b},
351	{18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e},
352	{30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d},
353	{49152, 0x011e}, {61440, 0x011f}
354};
355
356static u32 mpc_i2c_get_sec_cfg_8xxx(void)
357{
 
358	u32 __iomem *reg;
359	u32 val = 0;
360
361	struct device_node *node __free(device_node) =
362		of_find_node_by_name(NULL, "global-utilities");
363	if (node) {
364		const u32 *prop = of_get_property(node, "reg", NULL);
365		if (prop) {
366			/*
367			 * Map and check POR Device Status Register 2
368			 * (PORDEVSR2) at 0xE0014. Note than while MPC8533
369			 * and MPC8544 indicate SEC frequency ratio
370			 * configuration as bit 26 in PORDEVSR2, other MPC8xxx
371			 * parts may store it differently or may not have it
372			 * at all.
373			 */
374			reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
375			if (!reg)
376				printk(KERN_ERR
377				       "Error: couldn't map PORDEVSR2\n");
378			else
379				val = in_be32(reg) & 0x00000020; /* sec-cfg */
380			iounmap(reg);
381		}
382	}
 
383
384	return val;
385}
386
387static u32 mpc_i2c_get_prescaler_8xxx(void)
388{
389	/*
390	 * According to the AN2919 all MPC824x have prescaler 1, while MPC83xx
391	 * may have prescaler 1, 2, or 3, depending on the power-on
392	 * configuration.
393	 */
394	u32 prescaler = 1;
395
396	/* mpc85xx */
397	if (pvr_version_is(PVR_VER_E500V1) || pvr_version_is(PVR_VER_E500V2)
398		|| pvr_version_is(PVR_VER_E500MC)
399		|| pvr_version_is(PVR_VER_E5500)
400		|| pvr_version_is(PVR_VER_E6500)) {
401		unsigned int svr = mfspr(SPRN_SVR);
402
403		if ((SVR_SOC_VER(svr) == SVR_8540)
404			|| (SVR_SOC_VER(svr) == SVR_8541)
405			|| (SVR_SOC_VER(svr) == SVR_8560)
406			|| (SVR_SOC_VER(svr) == SVR_8555)
407			|| (SVR_SOC_VER(svr) == SVR_8610))
408			/* the above 85xx SoCs have prescaler 1 */
409			prescaler = 1;
410		else if ((SVR_SOC_VER(svr) == SVR_8533)
411			|| (SVR_SOC_VER(svr) == SVR_8544))
412			/* the above 85xx SoCs have prescaler 3 or 2 */
413			prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2;
414		else
415			/* all the other 85xx have prescaler 2 */
416			prescaler = 2;
417	}
418
419	return prescaler;
420}
421
422static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
423					  u32 *real_clk)
424{
425	const struct mpc_i2c_divider *div = NULL;
426	u32 prescaler = mpc_i2c_get_prescaler_8xxx();
427	u32 divider;
428	int i;
429
430	if (clock == MPC_I2C_CLOCK_LEGACY) {
431		/* see below - default fdr = 0x1031 -> div = 16 * 3072 */
432		*real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072);
433		return -EINVAL;
434	}
435
436	divider = fsl_get_sys_freq() / clock / prescaler;
437
438	pr_debug("I2C: src_clock=%d clock=%d divider=%d\n",
439		 fsl_get_sys_freq(), clock, divider);
440
441	/*
442	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
443	 * is equal to or lower than the requested speed.
444	 */
445	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) {
446		div = &mpc_i2c_dividers_8xxx[i];
447		if (div->divider >= divider)
448			break;
449	}
450
451	*real_clk = fsl_get_sys_freq() / prescaler / div->divider;
452	return (int)div->fdr;
453}
454
455static void mpc_i2c_setup_8xxx(struct device_node *node,
456					 struct mpc_i2c *i2c,
457					 u32 clock)
458{
459	int ret, fdr;
460
461	if (clock == MPC_I2C_CLOCK_PRESERVE) {
462		dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n",
463			readb(i2c->base + MPC_I2C_DFSRR),
464			readb(i2c->base + MPC_I2C_FDR));
465		return;
466	}
467
468	ret = mpc_i2c_get_fdr_8xxx(node, clock, &i2c->real_clk);
469	fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
470
471	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
472	writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR);
473
474	if (ret >= 0)
475		dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
476			 i2c->real_clk, fdr >> 8, fdr & 0xff);
477}
478
479#else /* !CONFIG_FSL_SOC */
480static void mpc_i2c_setup_8xxx(struct device_node *node,
481					 struct mpc_i2c *i2c,
482					 u32 clock)
483{
484}
485#endif /* CONFIG_FSL_SOC */
486
487static void mpc_i2c_finish(struct mpc_i2c *i2c, int rc)
488{
489	i2c->rc = rc;
490	i2c->block = 0;
491	i2c->cntl_bits = CCR_MEN;
492	writeccr(i2c, i2c->cntl_bits);
493	wake_up(&i2c->waitq);
494}
495
496static void mpc_i2c_do_action(struct mpc_i2c *i2c)
497{
498	struct i2c_msg *msg = NULL;
499	int dir = 0;
500	int recv_len = 0;
501	u8 byte;
502
503	dev_dbg(i2c->dev, "action = %s\n", action_str[i2c->action]);
504
505	i2c->cntl_bits &= ~(CCR_RSTA | CCR_MTX | CCR_TXAK);
506
507	if (i2c->action != MPC_I2C_ACTION_STOP) {
508		msg = &i2c->msgs[i2c->curr_msg];
509		if (msg->flags & I2C_M_RD)
510			dir = 1;
511		if (msg->flags & I2C_M_RECV_LEN)
512			recv_len = 1;
513	}
514
515	switch (i2c->action) {
516	case MPC_I2C_ACTION_RESTART:
517		i2c->cntl_bits |= CCR_RSTA;
518		fallthrough;
519
520	case MPC_I2C_ACTION_START:
521		i2c->cntl_bits |= CCR_MSTA | CCR_MTX;
522		writeccr(i2c, i2c->cntl_bits);
523		writeb((msg->addr << 1) | dir, i2c->base + MPC_I2C_DR);
524		i2c->expect_rxack = 1;
525		i2c->action = dir ? MPC_I2C_ACTION_READ_BEGIN : MPC_I2C_ACTION_WRITE;
526		break;
527
528	case MPC_I2C_ACTION_READ_BEGIN:
529		if (msg->len) {
530			if (msg->len == 1 && !(msg->flags & I2C_M_RECV_LEN))
531				i2c->cntl_bits |= CCR_TXAK;
532
533			writeccr(i2c, i2c->cntl_bits);
534			/* Dummy read */
535			readb(i2c->base + MPC_I2C_DR);
536		}
537		i2c->action = MPC_I2C_ACTION_READ_BYTE;
538		break;
539
540	case MPC_I2C_ACTION_READ_BYTE:
541		if (i2c->byte_posn || !recv_len) {
542			/* Generate Tx ACK on next to last byte */
543			if (i2c->byte_posn == msg->len - 2)
544				i2c->cntl_bits |= CCR_TXAK;
545			/* Do not generate stop on last byte */
546			if (i2c->byte_posn == msg->len - 1)
547				i2c->cntl_bits |= CCR_MTX;
548
549			writeccr(i2c, i2c->cntl_bits);
550		}
551
552		byte = readb(i2c->base + MPC_I2C_DR);
553
554		if (i2c->byte_posn == 0 && recv_len) {
555			if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) {
556				mpc_i2c_finish(i2c, -EPROTO);
557				return;
558			}
559			msg->len += byte;
560			/*
561			 * For block reads, generate Tx ACK here if data length
562			 * is 1 byte (total length is 2 bytes).
563			 */
564			if (msg->len == 2) {
565				i2c->cntl_bits |= CCR_TXAK;
566				writeccr(i2c, i2c->cntl_bits);
567			}
568		}
569
570		dev_dbg(i2c->dev, "%s %02x\n", action_str[i2c->action], byte);
571		msg->buf[i2c->byte_posn++] = byte;
572		break;
573
574	case MPC_I2C_ACTION_WRITE:
575		dev_dbg(i2c->dev, "%s %02x\n", action_str[i2c->action],
576			msg->buf[i2c->byte_posn]);
577		writeb(msg->buf[i2c->byte_posn++], i2c->base + MPC_I2C_DR);
578		i2c->expect_rxack = 1;
579		break;
580
581	case MPC_I2C_ACTION_STOP:
582		mpc_i2c_finish(i2c, 0);
583		break;
584
585	default:
586		WARN(1, "Unexpected action %d\n", i2c->action);
587		break;
588	}
589
590	if (msg && msg->len == i2c->byte_posn) {
591		i2c->curr_msg++;
592		i2c->byte_posn = 0;
593
594		if (i2c->curr_msg == i2c->num_msgs) {
595			i2c->action = MPC_I2C_ACTION_STOP;
596			/*
597			 * We don't get another interrupt on read so
598			 * finish the transfer now
599			 */
600			if (dir)
601				mpc_i2c_finish(i2c, 0);
602		} else {
603			i2c->action = MPC_I2C_ACTION_RESTART;
604		}
605	}
606}
607
608static void mpc_i2c_do_intr(struct mpc_i2c *i2c, u8 status)
609{
610	spin_lock(&i2c->lock);
611
612	if (!(status & CSR_MCF)) {
613		dev_dbg(i2c->dev, "unfinished\n");
614		mpc_i2c_finish(i2c, -EIO);
615		goto out;
616	}
617
618	if (status & CSR_MAL) {
619		dev_dbg(i2c->dev, "arbitration lost\n");
620		mpc_i2c_finish(i2c, -EAGAIN);
621		goto out;
622	}
623
624	if (i2c->expect_rxack && (status & CSR_RXAK)) {
625		dev_dbg(i2c->dev, "no Rx ACK\n");
626		mpc_i2c_finish(i2c, -ENXIO);
627		goto out;
628	}
629	i2c->expect_rxack = 0;
630
631	mpc_i2c_do_action(i2c);
632
633out:
634	spin_unlock(&i2c->lock);
635}
636
637static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
638{
639	struct mpc_i2c *i2c = dev_id;
640	u8 status;
641
642	status = readb(i2c->base + MPC_I2C_SR);
643	if (status & CSR_MIF) {
644		/* Wait up to 100us for transfer to properly complete */
645		readb_poll_timeout_atomic(i2c->base + MPC_I2C_SR, status, status & CSR_MCF, 0, 100);
646		writeb(0, i2c->base + MPC_I2C_SR);
647		mpc_i2c_do_intr(i2c, status);
648		return IRQ_HANDLED;
649	}
650	return IRQ_NONE;
651}
652
653static int mpc_i2c_wait_for_completion(struct mpc_i2c *i2c)
654{
655	long time_left;
656
657	time_left = wait_event_timeout(i2c->waitq, !i2c->block, i2c->adap.timeout);
658	if (!time_left)
659		return -ETIMEDOUT;
660	if (time_left < 0)
661		return time_left;
662
663	return 0;
664}
665
666static int mpc_i2c_execute_msg(struct mpc_i2c *i2c)
667{
668	unsigned long orig_jiffies;
669	unsigned long flags;
670	int ret;
671
672	spin_lock_irqsave(&i2c->lock, flags);
673
674	i2c->curr_msg = 0;
675	i2c->rc = 0;
676	i2c->byte_posn = 0;
677	i2c->block = 1;
678	i2c->action = MPC_I2C_ACTION_START;
679
680	i2c->cntl_bits = CCR_MEN | CCR_MIEN;
681	writeb(0, i2c->base + MPC_I2C_SR);
682	writeccr(i2c, i2c->cntl_bits);
683
684	mpc_i2c_do_action(i2c);
685
686	spin_unlock_irqrestore(&i2c->lock, flags);
687
688	ret = mpc_i2c_wait_for_completion(i2c);
689	if (ret)
690		i2c->rc = ret;
691
692	if (i2c->rc == -EIO || i2c->rc == -EAGAIN || i2c->rc == -ETIMEDOUT)
693		i2c_recover_bus(&i2c->adap);
694
695	orig_jiffies = jiffies;
696	/* Wait until STOP is seen, allow up to 1 s */
697	while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
698		if (time_after(jiffies, orig_jiffies + HZ)) {
699			u8 status = readb(i2c->base + MPC_I2C_SR);
700
701			dev_dbg(i2c->dev, "timeout\n");
702			if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
703				writeb(status & ~CSR_MAL,
704				       i2c->base + MPC_I2C_SR);
705				i2c_recover_bus(&i2c->adap);
706			}
707			return -EIO;
708		}
709		cond_resched();
710	}
711
712	return i2c->rc;
713}
714
715static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
716{
717	int rc, ret = num;
718	struct mpc_i2c *i2c = i2c_get_adapdata(adap);
719	int i;
720
721	dev_dbg(i2c->dev, "num = %d\n", num);
722	for (i = 0; i < num; i++)
723		dev_dbg(i2c->dev, "  addr = %02x, flags = %02x, len = %d, %*ph\n",
724			msgs[i].addr, msgs[i].flags, msgs[i].len,
725			msgs[i].flags & I2C_M_RD ? 0 : msgs[i].len,
726			msgs[i].buf);
727
728	WARN_ON(i2c->msgs != NULL);
729	i2c->msgs = msgs;
730	i2c->num_msgs = num;
731
732	rc = mpc_i2c_execute_msg(i2c);
733	if (rc < 0)
734		ret = rc;
735
736	i2c->num_msgs = 0;
737	i2c->msgs = NULL;
738
739	return ret;
740}
741
742static u32 mpc_functionality(struct i2c_adapter *adap)
743{
744	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
745	  | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
746}
747
748static int fsl_i2c_bus_recovery(struct i2c_adapter *adap)
749{
750	struct mpc_i2c *i2c = i2c_get_adapdata(adap);
751
752	if (i2c->has_errata_A004447)
753		mpc_i2c_fixup_A004447(i2c);
754	else
755		mpc_i2c_fixup(i2c);
756
757	return 0;
758}
759
760static const struct i2c_algorithm mpc_algo = {
761	.xfer = mpc_xfer,
762	.functionality = mpc_functionality,
763};
764
765static struct i2c_adapter mpc_ops = {
766	.owner = THIS_MODULE,
767	.algo = &mpc_algo,
 
768};
769
770static struct i2c_bus_recovery_info fsl_i2c_recovery_info = {
771	.recover_bus = fsl_i2c_bus_recovery,
772};
773
774static int fsl_i2c_probe(struct platform_device *op)
775{
776	const struct mpc_i2c_data *data;
777	struct mpc_i2c *i2c;
 
 
 
 
778	struct clk *clk;
779	int result;
780	u32 clock;
781
782	i2c = devm_kzalloc(&op->dev, sizeof(*i2c), GFP_KERNEL);
783	if (!i2c)
784		return -ENOMEM;
785
786	i2c->dev = &op->dev; /* for debug and error output */
787
788	init_waitqueue_head(&i2c->waitq);
789	spin_lock_init(&i2c->lock);
790
791	i2c->base = devm_platform_ioremap_resource(op, 0);
792	if (IS_ERR(i2c->base))
793		return PTR_ERR(i2c->base);
794
795	i2c->irq = platform_get_irq(op, 0);
796	if (i2c->irq < 0)
797		return i2c->irq;
798
799	result = devm_request_irq(&op->dev, i2c->irq, mpc_i2c_isr,
800			IRQF_SHARED, "i2c-mpc", i2c);
801	if (result < 0) {
802		dev_err(i2c->dev, "failed to attach interrupt\n");
803		return result;
804	}
805
806	/*
807	 * enable clock for the I2C peripheral (non fatal),
808	 * keep a reference upon successful allocation
809	 */
810	clk = devm_clk_get_optional_enabled(&op->dev, NULL);
811	if (IS_ERR(clk)) {
812		dev_err(&op->dev, "failed to enable clock\n");
813		return PTR_ERR(clk);
 
 
 
 
 
814	}
815
 
 
816	if (of_property_read_bool(op->dev.of_node, "fsl,preserve-clocking")) {
817		clock = MPC_I2C_CLOCK_PRESERVE;
818	} else {
819		result = of_property_read_u32(op->dev.of_node,
820					      "clock-frequency", &clock);
821		if (result)
822			clock = MPC_I2C_CLOCK_LEGACY;
823	}
824
825	data = device_get_match_data(&op->dev);
826	if (data) {
827		data->setup(op->dev.of_node, i2c, clock);
828	} else {
829		/* Backwards compatibility */
830		if (of_property_read_bool(op->dev.of_node, "dfsrr"))
831			mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock);
832	}
833
834	/* Sadly, we have to support two deprecated bindings here */
835	result = of_property_read_u32(op->dev.of_node,
836				      "i2c-transfer-timeout-us",
837				      &mpc_ops.timeout);
838	if (result == -EINVAL)
839		result = of_property_read_u32(op->dev.of_node,
840					      "i2c-scl-clk-low-timeout-us",
841					      &mpc_ops.timeout);
842	if (result == -EINVAL)
843		result = of_property_read_u32(op->dev.of_node,
844					      "fsl,timeout", &mpc_ops.timeout);
845
846	if (!result) {
847		mpc_ops.timeout *= HZ / 1000000;
848		if (mpc_ops.timeout < 5)
849			mpc_ops.timeout = 5;
850	} else {
851		mpc_ops.timeout = HZ;
852	}
853
854	dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ);
855
856	if (of_property_read_bool(op->dev.of_node, "fsl,i2c-erratum-a004447"))
857		i2c->has_errata_A004447 = true;
858
859	i2c->adap = mpc_ops;
860	scnprintf(i2c->adap.name, sizeof(i2c->adap.name),
861		  "MPC adapter (%s)", of_node_full_name(op->dev.of_node));
862	i2c->adap.dev.parent = &op->dev;
863	i2c->adap.nr = op->id;
864	i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
865	i2c->adap.bus_recovery_info = &fsl_i2c_recovery_info;
866	platform_set_drvdata(op, i2c);
867	i2c_set_adapdata(&i2c->adap, i2c);
868
869	result = i2c_add_numbered_adapter(&i2c->adap);
870	if (result)
871		return result;
872
873	return 0;
 
 
 
 
 
874};
875
876static void fsl_i2c_remove(struct platform_device *op)
877{
878	struct mpc_i2c *i2c = platform_get_drvdata(op);
879
880	i2c_del_adapter(&i2c->adap);
 
 
 
 
881};
882
883static int __maybe_unused mpc_i2c_suspend(struct device *dev)
884{
885	struct mpc_i2c *i2c = dev_get_drvdata(dev);
886
887	i2c->fdr = readb(i2c->base + MPC_I2C_FDR);
888	i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR);
889
890	return 0;
891}
892
893static int __maybe_unused mpc_i2c_resume(struct device *dev)
894{
895	struct mpc_i2c *i2c = dev_get_drvdata(dev);
896
897	writeb(i2c->fdr, i2c->base + MPC_I2C_FDR);
898	writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR);
899
900	return 0;
901}
902static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
903
904static const struct mpc_i2c_data mpc_i2c_data_512x = {
905	.setup = mpc_i2c_setup_512x,
906};
907
908static const struct mpc_i2c_data mpc_i2c_data_52xx = {
909	.setup = mpc_i2c_setup_52xx,
910};
911
912static const struct mpc_i2c_data mpc_i2c_data_8313 = {
913	.setup = mpc_i2c_setup_8xxx,
914};
915
916static const struct mpc_i2c_data mpc_i2c_data_8543 = {
917	.setup = mpc_i2c_setup_8xxx,
918};
919
920static const struct mpc_i2c_data mpc_i2c_data_8544 = {
921	.setup = mpc_i2c_setup_8xxx,
922};
923
924static const struct of_device_id mpc_i2c_of_match[] = {
925	{.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
926	{.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, },
927	{.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
928	{.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, },
929	{.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, },
930	{.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, },
931	{.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, },
932	/* Backward compatibility */
933	{.compatible = "fsl-i2c", },
934	{},
935};
936MODULE_DEVICE_TABLE(of, mpc_i2c_of_match);
937
938/* Structure for a device driver */
939static struct platform_driver mpc_i2c_driver = {
940	.probe		= fsl_i2c_probe,
941	.remove		= fsl_i2c_remove,
942	.driver = {
943		.name = "mpc-i2c",
944		.of_match_table = mpc_i2c_of_match,
945		.pm = &mpc_i2c_pm_ops,
946	},
947};
948
949module_platform_driver(mpc_i2c_driver);
950
951MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>");
952MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and "
953		   "MPC824x/83xx/85xx/86xx/512x/52xx processors");
954MODULE_LICENSE("GPL");
v6.2
  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * This is a combined i2c adapter and algorithm driver for the
  4 * MPC107/Tsi107 PowerPC northbridge and processors that include
  5 * the same I2C unit (8240, 8245, 85xx).
  6 *
  7 * Copyright (C) 2003-2004 Humboldt Solutions Ltd, adrian@humboldt.co.uk
  8 * Copyright (C) 2021 Allied Telesis Labs
  9 */
 10
 11#include <linux/kernel.h>
 12#include <linux/module.h>
 13#include <linux/sched/signal.h>
 
 14#include <linux/of_address.h>
 15#include <linux/of_irq.h>
 16#include <linux/of_platform.h>
 17#include <linux/property.h>
 18#include <linux/slab.h>
 19
 20#include <linux/clk.h>
 21#include <linux/io.h>
 22#include <linux/iopoll.h>
 23#include <linux/fsl_devices.h>
 24#include <linux/i2c.h>
 25#include <linux/interrupt.h>
 26#include <linux/delay.h>
 27
 28#include <asm/mpc52xx.h>
 29#include <asm/mpc85xx.h>
 30#include <sysdev/fsl_soc.h>
 31
 32#define DRV_NAME "mpc-i2c"
 33
 34#define MPC_I2C_CLOCK_LEGACY   0
 35#define MPC_I2C_CLOCK_PRESERVE (~0U)
 36
 37#define MPC_I2C_FDR   0x04
 38#define MPC_I2C_CR    0x08
 39#define MPC_I2C_SR    0x0c
 40#define MPC_I2C_DR    0x10
 41#define MPC_I2C_DFSRR 0x14
 42
 43#define CCR_MEN  0x80
 44#define CCR_MIEN 0x40
 45#define CCR_MSTA 0x20
 46#define CCR_MTX  0x10
 47#define CCR_TXAK 0x08
 48#define CCR_RSTA 0x04
 49#define CCR_RSVD 0x02
 50
 51#define CSR_MCF  0x80
 52#define CSR_MAAS 0x40
 53#define CSR_MBB  0x20
 54#define CSR_MAL  0x10
 55#define CSR_SRW  0x04
 56#define CSR_MIF  0x02
 57#define CSR_RXAK 0x01
 58
 59enum mpc_i2c_action {
 60	MPC_I2C_ACTION_START = 1,
 61	MPC_I2C_ACTION_RESTART,
 62	MPC_I2C_ACTION_READ_BEGIN,
 63	MPC_I2C_ACTION_READ_BYTE,
 64	MPC_I2C_ACTION_WRITE,
 65	MPC_I2C_ACTION_STOP,
 66
 67	__MPC_I2C_ACTION_CNT
 68};
 69
 70static const char * const action_str[] = {
 71	"invalid",
 72	"start",
 73	"restart",
 74	"read begin",
 75	"read",
 76	"write",
 77	"stop",
 78};
 79
 80static_assert(ARRAY_SIZE(action_str) == __MPC_I2C_ACTION_CNT);
 81
 82struct mpc_i2c {
 83	struct device *dev;
 84	void __iomem *base;
 85	u32 interrupt;
 86	wait_queue_head_t waitq;
 87	spinlock_t lock;
 88	struct i2c_adapter adap;
 89	int irq;
 90	u32 real_clk;
 91	u8 fdr, dfsrr;
 92	struct clk *clk_per;
 93	u32 cntl_bits;
 94	enum mpc_i2c_action action;
 95	struct i2c_msg *msgs;
 96	int num_msgs;
 97	int curr_msg;
 98	u32 byte_posn;
 99	u32 block;
100	int rc;
101	int expect_rxack;
102	bool has_errata_A004447;
103};
104
105struct mpc_i2c_divider {
106	u16 divider;
107	u16 fdr;	/* including dfsrr */
108};
109
110struct mpc_i2c_data {
111	void (*setup)(struct device_node *node, struct mpc_i2c *i2c, u32 clock);
112};
113
114static inline void writeccr(struct mpc_i2c *i2c, u32 x)
115{
116	writeb(x, i2c->base + MPC_I2C_CR);
117}
118
119/* Sometimes 9th clock pulse isn't generated, and slave doesn't release
120 * the bus, because it wants to send ACK.
121 * Following sequence of enabling/disabling and sending start/stop generates
122 * the 9 pulses, each with a START then ending with STOP, so it's all OK.
123 */
124static void mpc_i2c_fixup(struct mpc_i2c *i2c)
125{
126	int k;
127	unsigned long flags;
128
129	for (k = 9; k; k--) {
130		writeccr(i2c, 0);
131		writeb(0, i2c->base + MPC_I2C_SR); /* clear any status bits */
132		writeccr(i2c, CCR_MEN | CCR_MSTA); /* START */
133		readb(i2c->base + MPC_I2C_DR); /* init xfer */
134		udelay(15); /* let it hit the bus */
135		local_irq_save(flags); /* should not be delayed further */
136		writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSTA); /* delay SDA */
137		readb(i2c->base + MPC_I2C_DR);
138		if (k != 1)
139			udelay(5);
140		local_irq_restore(flags);
141	}
142	writeccr(i2c, CCR_MEN); /* Initiate STOP */
143	readb(i2c->base + MPC_I2C_DR);
144	udelay(15); /* Let STOP propagate */
145	writeccr(i2c, 0);
146}
147
148static int i2c_mpc_wait_sr(struct mpc_i2c *i2c, int mask)
149{
150	void __iomem *addr = i2c->base + MPC_I2C_SR;
151	u8 val;
152
153	return readb_poll_timeout(addr, val, val & mask, 0, 100);
154}
155
156/*
157 * Workaround for Erratum A004447. From the P2040CE Rev Q
158 *
159 * 1.  Set up the frequency divider and sampling rate.
160 * 2.  I2CCR - a0h
161 * 3.  Poll for I2CSR[MBB] to get set.
162 * 4.  If I2CSR[MAL] is set (an indication that SDA is stuck low), then go to
163 *     step 5. If MAL is not set, then go to step 13.
164 * 5.  I2CCR - 00h
165 * 6.  I2CCR - 22h
166 * 7.  I2CCR - a2h
167 * 8.  Poll for I2CSR[MBB] to get set.
168 * 9.  Issue read to I2CDR.
169 * 10. Poll for I2CSR[MIF] to be set.
170 * 11. I2CCR - 82h
171 * 12. Workaround complete. Skip the next steps.
172 * 13. Issue read to I2CDR.
173 * 14. Poll for I2CSR[MIF] to be set.
174 * 15. I2CCR - 80h
175 */
176static void mpc_i2c_fixup_A004447(struct mpc_i2c *i2c)
177{
178	int ret;
179	u32 val;
180
181	writeccr(i2c, CCR_MEN | CCR_MSTA);
182	ret = i2c_mpc_wait_sr(i2c, CSR_MBB);
183	if (ret) {
184		dev_err(i2c->dev, "timeout waiting for CSR_MBB\n");
185		return;
186	}
187
188	val = readb(i2c->base + MPC_I2C_SR);
189
190	if (val & CSR_MAL) {
191		writeccr(i2c, 0x00);
192		writeccr(i2c, CCR_MSTA | CCR_RSVD);
193		writeccr(i2c, CCR_MEN | CCR_MSTA | CCR_RSVD);
194		ret = i2c_mpc_wait_sr(i2c, CSR_MBB);
195		if (ret) {
196			dev_err(i2c->dev, "timeout waiting for CSR_MBB\n");
197			return;
198		}
199		val = readb(i2c->base + MPC_I2C_DR);
200		ret = i2c_mpc_wait_sr(i2c, CSR_MIF);
201		if (ret) {
202			dev_err(i2c->dev, "timeout waiting for CSR_MIF\n");
203			return;
204		}
205		writeccr(i2c, CCR_MEN | CCR_RSVD);
206	} else {
207		val = readb(i2c->base + MPC_I2C_DR);
208		ret = i2c_mpc_wait_sr(i2c, CSR_MIF);
209		if (ret) {
210			dev_err(i2c->dev, "timeout waiting for CSR_MIF\n");
211			return;
212		}
213		writeccr(i2c, CCR_MEN);
214	}
215}
216
217#if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
218static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] = {
219	{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
220	{28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
221	{36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28},
222	{52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a},
223	{68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09},
224	{96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81},
225	{128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30},
226	{176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32},
227	{240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10},
228	{320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a},
229	{448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14},
230	{640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17},
231	{1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d},
232	{1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c},
233	{2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f},
234	{4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e},
235	{7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c},
236	{10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f}
237};
238
239static int mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
240					  u32 *real_clk)
241{
242	struct fwnode_handle *fwnode = of_fwnode_handle(node);
243	const struct mpc_i2c_divider *div = NULL;
244	unsigned int pvr = mfspr(SPRN_PVR);
245	u32 divider;
246	int i;
247
248	if (clock == MPC_I2C_CLOCK_LEGACY) {
249		/* see below - default fdr = 0x3f -> div = 2048 */
250		*real_clk = mpc5xxx_fwnode_get_bus_frequency(fwnode) / 2048;
251		return -EINVAL;
252	}
253
254	/* Determine divider value */
255	divider = mpc5xxx_fwnode_get_bus_frequency(fwnode) / clock;
256
257	/*
258	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
259	 * is equal to or lower than the requested speed.
260	 */
261	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) {
262		div = &mpc_i2c_dividers_52xx[i];
263		/* Old MPC5200 rev A CPUs do not support the high bits */
264		if (div->fdr & 0xc0 && pvr == 0x80822011)
265			continue;
266		if (div->divider >= divider)
267			break;
268	}
269
270	*real_clk = mpc5xxx_fwnode_get_bus_frequency(fwnode) / div->divider;
271	return (int)div->fdr;
272}
273
274static void mpc_i2c_setup_52xx(struct device_node *node,
275					 struct mpc_i2c *i2c,
276					 u32 clock)
277{
278	int ret, fdr;
279
280	if (clock == MPC_I2C_CLOCK_PRESERVE) {
281		dev_dbg(i2c->dev, "using fdr %d\n",
282			readb(i2c->base + MPC_I2C_FDR));
283		return;
284	}
285
286	ret = mpc_i2c_get_fdr_52xx(node, clock, &i2c->real_clk);
287	fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
288
289	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
290
291	if (ret >= 0)
292		dev_info(i2c->dev, "clock %u Hz (fdr=%d)\n", i2c->real_clk,
293			 fdr);
294}
295#else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
296static void mpc_i2c_setup_52xx(struct device_node *node,
297					 struct mpc_i2c *i2c,
298					 u32 clock)
299{
300}
301#endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
302
303#ifdef CONFIG_PPC_MPC512x
304static void mpc_i2c_setup_512x(struct device_node *node,
305					 struct mpc_i2c *i2c,
306					 u32 clock)
307{
308	struct device_node *node_ctrl;
309	void __iomem *ctrl;
310	const u32 *pval;
311	u32 idx;
312
313	/* Enable I2C interrupts for mpc5121 */
314	node_ctrl = of_find_compatible_node(NULL, NULL,
315					    "fsl,mpc5121-i2c-ctrl");
316	if (node_ctrl) {
317		ctrl = of_iomap(node_ctrl, 0);
318		if (ctrl) {
 
319			/* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */
320			pval = of_get_property(node, "reg", NULL);
321			idx = (*pval & 0xff) / 0x20;
322			setbits32(ctrl, 1 << (24 + idx * 2));
323			iounmap(ctrl);
324		}
325		of_node_put(node_ctrl);
326	}
327
328	/* The clock setup for the 52xx works also fine for the 512x */
329	mpc_i2c_setup_52xx(node, i2c, clock);
330}
331#else /* CONFIG_PPC_MPC512x */
332static void mpc_i2c_setup_512x(struct device_node *node,
333					 struct mpc_i2c *i2c,
334					 u32 clock)
335{
336}
337#endif /* CONFIG_PPC_MPC512x */
338
339#ifdef CONFIG_FSL_SOC
340static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] = {
341	{160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123},
342	{288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102},
343	{416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127},
344	{544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105},
345	{672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106},
346	{800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107},
347	{1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07},
348	{1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a},
349	{1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b},
350	{2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e},
351	{3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133},
352	{4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136},
353	{7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115},
354	{12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b},
355	{18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e},
356	{30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d},
357	{49152, 0x011e}, {61440, 0x011f}
358};
359
360static u32 mpc_i2c_get_sec_cfg_8xxx(void)
361{
362	struct device_node *node;
363	u32 __iomem *reg;
364	u32 val = 0;
365
366	node = of_find_node_by_name(NULL, "global-utilities");
 
367	if (node) {
368		const u32 *prop = of_get_property(node, "reg", NULL);
369		if (prop) {
370			/*
371			 * Map and check POR Device Status Register 2
372			 * (PORDEVSR2) at 0xE0014. Note than while MPC8533
373			 * and MPC8544 indicate SEC frequency ratio
374			 * configuration as bit 26 in PORDEVSR2, other MPC8xxx
375			 * parts may store it differently or may not have it
376			 * at all.
377			 */
378			reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
379			if (!reg)
380				printk(KERN_ERR
381				       "Error: couldn't map PORDEVSR2\n");
382			else
383				val = in_be32(reg) & 0x00000020; /* sec-cfg */
384			iounmap(reg);
385		}
386	}
387	of_node_put(node);
388
389	return val;
390}
391
392static u32 mpc_i2c_get_prescaler_8xxx(void)
393{
394	/*
395	 * According to the AN2919 all MPC824x have prescaler 1, while MPC83xx
396	 * may have prescaler 1, 2, or 3, depending on the power-on
397	 * configuration.
398	 */
399	u32 prescaler = 1;
400
401	/* mpc85xx */
402	if (pvr_version_is(PVR_VER_E500V1) || pvr_version_is(PVR_VER_E500V2)
403		|| pvr_version_is(PVR_VER_E500MC)
404		|| pvr_version_is(PVR_VER_E5500)
405		|| pvr_version_is(PVR_VER_E6500)) {
406		unsigned int svr = mfspr(SPRN_SVR);
407
408		if ((SVR_SOC_VER(svr) == SVR_8540)
409			|| (SVR_SOC_VER(svr) == SVR_8541)
410			|| (SVR_SOC_VER(svr) == SVR_8560)
411			|| (SVR_SOC_VER(svr) == SVR_8555)
412			|| (SVR_SOC_VER(svr) == SVR_8610))
413			/* the above 85xx SoCs have prescaler 1 */
414			prescaler = 1;
415		else if ((SVR_SOC_VER(svr) == SVR_8533)
416			|| (SVR_SOC_VER(svr) == SVR_8544))
417			/* the above 85xx SoCs have prescaler 3 or 2 */
418			prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2;
419		else
420			/* all the other 85xx have prescaler 2 */
421			prescaler = 2;
422	}
423
424	return prescaler;
425}
426
427static int mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
428					  u32 *real_clk)
429{
430	const struct mpc_i2c_divider *div = NULL;
431	u32 prescaler = mpc_i2c_get_prescaler_8xxx();
432	u32 divider;
433	int i;
434
435	if (clock == MPC_I2C_CLOCK_LEGACY) {
436		/* see below - default fdr = 0x1031 -> div = 16 * 3072 */
437		*real_clk = fsl_get_sys_freq() / prescaler / (16 * 3072);
438		return -EINVAL;
439	}
440
441	divider = fsl_get_sys_freq() / clock / prescaler;
442
443	pr_debug("I2C: src_clock=%d clock=%d divider=%d\n",
444		 fsl_get_sys_freq(), clock, divider);
445
446	/*
447	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
448	 * is equal to or lower than the requested speed.
449	 */
450	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) {
451		div = &mpc_i2c_dividers_8xxx[i];
452		if (div->divider >= divider)
453			break;
454	}
455
456	*real_clk = fsl_get_sys_freq() / prescaler / div->divider;
457	return (int)div->fdr;
458}
459
460static void mpc_i2c_setup_8xxx(struct device_node *node,
461					 struct mpc_i2c *i2c,
462					 u32 clock)
463{
464	int ret, fdr;
465
466	if (clock == MPC_I2C_CLOCK_PRESERVE) {
467		dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n",
468			readb(i2c->base + MPC_I2C_DFSRR),
469			readb(i2c->base + MPC_I2C_FDR));
470		return;
471	}
472
473	ret = mpc_i2c_get_fdr_8xxx(node, clock, &i2c->real_clk);
474	fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
475
476	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
477	writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR);
478
479	if (ret >= 0)
480		dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
481			 i2c->real_clk, fdr >> 8, fdr & 0xff);
482}
483
484#else /* !CONFIG_FSL_SOC */
485static void mpc_i2c_setup_8xxx(struct device_node *node,
486					 struct mpc_i2c *i2c,
487					 u32 clock)
488{
489}
490#endif /* CONFIG_FSL_SOC */
491
492static void mpc_i2c_finish(struct mpc_i2c *i2c, int rc)
493{
494	i2c->rc = rc;
495	i2c->block = 0;
496	i2c->cntl_bits = CCR_MEN;
497	writeccr(i2c, i2c->cntl_bits);
498	wake_up(&i2c->waitq);
499}
500
501static void mpc_i2c_do_action(struct mpc_i2c *i2c)
502{
503	struct i2c_msg *msg = NULL;
504	int dir = 0;
505	int recv_len = 0;
506	u8 byte;
507
508	dev_dbg(i2c->dev, "action = %s\n", action_str[i2c->action]);
509
510	i2c->cntl_bits &= ~(CCR_RSTA | CCR_MTX | CCR_TXAK);
511
512	if (i2c->action != MPC_I2C_ACTION_STOP) {
513		msg = &i2c->msgs[i2c->curr_msg];
514		if (msg->flags & I2C_M_RD)
515			dir = 1;
516		if (msg->flags & I2C_M_RECV_LEN)
517			recv_len = 1;
518	}
519
520	switch (i2c->action) {
521	case MPC_I2C_ACTION_RESTART:
522		i2c->cntl_bits |= CCR_RSTA;
523		fallthrough;
524
525	case MPC_I2C_ACTION_START:
526		i2c->cntl_bits |= CCR_MSTA | CCR_MTX;
527		writeccr(i2c, i2c->cntl_bits);
528		writeb((msg->addr << 1) | dir, i2c->base + MPC_I2C_DR);
529		i2c->expect_rxack = 1;
530		i2c->action = dir ? MPC_I2C_ACTION_READ_BEGIN : MPC_I2C_ACTION_WRITE;
531		break;
532
533	case MPC_I2C_ACTION_READ_BEGIN:
534		if (msg->len) {
535			if (msg->len == 1 && !(msg->flags & I2C_M_RECV_LEN))
536				i2c->cntl_bits |= CCR_TXAK;
537
538			writeccr(i2c, i2c->cntl_bits);
539			/* Dummy read */
540			readb(i2c->base + MPC_I2C_DR);
541		}
542		i2c->action = MPC_I2C_ACTION_READ_BYTE;
543		break;
544
545	case MPC_I2C_ACTION_READ_BYTE:
546		if (i2c->byte_posn || !recv_len) {
547			/* Generate Tx ACK on next to last byte */
548			if (i2c->byte_posn == msg->len - 2)
549				i2c->cntl_bits |= CCR_TXAK;
550			/* Do not generate stop on last byte */
551			if (i2c->byte_posn == msg->len - 1)
552				i2c->cntl_bits |= CCR_MTX;
553
554			writeccr(i2c, i2c->cntl_bits);
555		}
556
557		byte = readb(i2c->base + MPC_I2C_DR);
558
559		if (i2c->byte_posn == 0 && recv_len) {
560			if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX) {
561				mpc_i2c_finish(i2c, -EPROTO);
562				return;
563			}
564			msg->len += byte;
565			/*
566			 * For block reads, generate Tx ACK here if data length
567			 * is 1 byte (total length is 2 bytes).
568			 */
569			if (msg->len == 2) {
570				i2c->cntl_bits |= CCR_TXAK;
571				writeccr(i2c, i2c->cntl_bits);
572			}
573		}
574
575		dev_dbg(i2c->dev, "%s %02x\n", action_str[i2c->action], byte);
576		msg->buf[i2c->byte_posn++] = byte;
577		break;
578
579	case MPC_I2C_ACTION_WRITE:
580		dev_dbg(i2c->dev, "%s %02x\n", action_str[i2c->action],
581			msg->buf[i2c->byte_posn]);
582		writeb(msg->buf[i2c->byte_posn++], i2c->base + MPC_I2C_DR);
583		i2c->expect_rxack = 1;
584		break;
585
586	case MPC_I2C_ACTION_STOP:
587		mpc_i2c_finish(i2c, 0);
588		break;
589
590	default:
591		WARN(1, "Unexpected action %d\n", i2c->action);
592		break;
593	}
594
595	if (msg && msg->len == i2c->byte_posn) {
596		i2c->curr_msg++;
597		i2c->byte_posn = 0;
598
599		if (i2c->curr_msg == i2c->num_msgs) {
600			i2c->action = MPC_I2C_ACTION_STOP;
601			/*
602			 * We don't get another interrupt on read so
603			 * finish the transfer now
604			 */
605			if (dir)
606				mpc_i2c_finish(i2c, 0);
607		} else {
608			i2c->action = MPC_I2C_ACTION_RESTART;
609		}
610	}
611}
612
613static void mpc_i2c_do_intr(struct mpc_i2c *i2c, u8 status)
614{
615	spin_lock(&i2c->lock);
616
617	if (!(status & CSR_MCF)) {
618		dev_dbg(i2c->dev, "unfinished\n");
619		mpc_i2c_finish(i2c, -EIO);
620		goto out;
621	}
622
623	if (status & CSR_MAL) {
624		dev_dbg(i2c->dev, "arbitration lost\n");
625		mpc_i2c_finish(i2c, -EAGAIN);
626		goto out;
627	}
628
629	if (i2c->expect_rxack && (status & CSR_RXAK)) {
630		dev_dbg(i2c->dev, "no Rx ACK\n");
631		mpc_i2c_finish(i2c, -ENXIO);
632		goto out;
633	}
634	i2c->expect_rxack = 0;
635
636	mpc_i2c_do_action(i2c);
637
638out:
639	spin_unlock(&i2c->lock);
640}
641
642static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
643{
644	struct mpc_i2c *i2c = dev_id;
645	u8 status;
646
647	status = readb(i2c->base + MPC_I2C_SR);
648	if (status & CSR_MIF) {
649		/* Wait up to 100us for transfer to properly complete */
650		readb_poll_timeout_atomic(i2c->base + MPC_I2C_SR, status, status & CSR_MCF, 0, 100);
651		writeb(0, i2c->base + MPC_I2C_SR);
652		mpc_i2c_do_intr(i2c, status);
653		return IRQ_HANDLED;
654	}
655	return IRQ_NONE;
656}
657
658static int mpc_i2c_wait_for_completion(struct mpc_i2c *i2c)
659{
660	long time_left;
661
662	time_left = wait_event_timeout(i2c->waitq, !i2c->block, i2c->adap.timeout);
663	if (!time_left)
664		return -ETIMEDOUT;
665	if (time_left < 0)
666		return time_left;
667
668	return 0;
669}
670
671static int mpc_i2c_execute_msg(struct mpc_i2c *i2c)
672{
673	unsigned long orig_jiffies;
674	unsigned long flags;
675	int ret;
676
677	spin_lock_irqsave(&i2c->lock, flags);
678
679	i2c->curr_msg = 0;
680	i2c->rc = 0;
681	i2c->byte_posn = 0;
682	i2c->block = 1;
683	i2c->action = MPC_I2C_ACTION_START;
684
685	i2c->cntl_bits = CCR_MEN | CCR_MIEN;
686	writeb(0, i2c->base + MPC_I2C_SR);
687	writeccr(i2c, i2c->cntl_bits);
688
689	mpc_i2c_do_action(i2c);
690
691	spin_unlock_irqrestore(&i2c->lock, flags);
692
693	ret = mpc_i2c_wait_for_completion(i2c);
694	if (ret)
695		i2c->rc = ret;
696
697	if (i2c->rc == -EIO || i2c->rc == -EAGAIN || i2c->rc == -ETIMEDOUT)
698		i2c_recover_bus(&i2c->adap);
699
700	orig_jiffies = jiffies;
701	/* Wait until STOP is seen, allow up to 1 s */
702	while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
703		if (time_after(jiffies, orig_jiffies + HZ)) {
704			u8 status = readb(i2c->base + MPC_I2C_SR);
705
706			dev_dbg(i2c->dev, "timeout\n");
707			if ((status & (CSR_MCF | CSR_MBB | CSR_RXAK)) != 0) {
708				writeb(status & ~CSR_MAL,
709				       i2c->base + MPC_I2C_SR);
710				i2c_recover_bus(&i2c->adap);
711			}
712			return -EIO;
713		}
714		cond_resched();
715	}
716
717	return i2c->rc;
718}
719
720static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
721{
722	int rc, ret = num;
723	struct mpc_i2c *i2c = i2c_get_adapdata(adap);
724	int i;
725
726	dev_dbg(i2c->dev, "num = %d\n", num);
727	for (i = 0; i < num; i++)
728		dev_dbg(i2c->dev, "  addr = %02x, flags = %02x, len = %d, %*ph\n",
729			msgs[i].addr, msgs[i].flags, msgs[i].len,
730			msgs[i].flags & I2C_M_RD ? 0 : msgs[i].len,
731			msgs[i].buf);
732
733	WARN_ON(i2c->msgs != NULL);
734	i2c->msgs = msgs;
735	i2c->num_msgs = num;
736
737	rc = mpc_i2c_execute_msg(i2c);
738	if (rc < 0)
739		ret = rc;
740
741	i2c->num_msgs = 0;
742	i2c->msgs = NULL;
743
744	return ret;
745}
746
747static u32 mpc_functionality(struct i2c_adapter *adap)
748{
749	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL
750	  | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
751}
752
753static int fsl_i2c_bus_recovery(struct i2c_adapter *adap)
754{
755	struct mpc_i2c *i2c = i2c_get_adapdata(adap);
756
757	if (i2c->has_errata_A004447)
758		mpc_i2c_fixup_A004447(i2c);
759	else
760		mpc_i2c_fixup(i2c);
761
762	return 0;
763}
764
765static const struct i2c_algorithm mpc_algo = {
766	.master_xfer = mpc_xfer,
767	.functionality = mpc_functionality,
768};
769
770static struct i2c_adapter mpc_ops = {
771	.owner = THIS_MODULE,
772	.algo = &mpc_algo,
773	.timeout = HZ,
774};
775
776static struct i2c_bus_recovery_info fsl_i2c_recovery_info = {
777	.recover_bus = fsl_i2c_bus_recovery,
778};
779
780static int fsl_i2c_probe(struct platform_device *op)
781{
782	const struct mpc_i2c_data *data;
783	struct mpc_i2c *i2c;
784	const u32 *prop;
785	u32 clock = MPC_I2C_CLOCK_LEGACY;
786	int result = 0;
787	int plen;
788	struct clk *clk;
789	int err;
 
790
791	i2c = devm_kzalloc(&op->dev, sizeof(*i2c), GFP_KERNEL);
792	if (!i2c)
793		return -ENOMEM;
794
795	i2c->dev = &op->dev; /* for debug and error output */
796
797	init_waitqueue_head(&i2c->waitq);
798	spin_lock_init(&i2c->lock);
799
800	i2c->base = devm_platform_ioremap_resource(op, 0);
801	if (IS_ERR(i2c->base))
802		return PTR_ERR(i2c->base);
803
804	i2c->irq = platform_get_irq(op, 0);
805	if (i2c->irq < 0)
806		return i2c->irq;
807
808	result = devm_request_irq(&op->dev, i2c->irq, mpc_i2c_isr,
809			IRQF_SHARED, "i2c-mpc", i2c);
810	if (result < 0) {
811		dev_err(i2c->dev, "failed to attach interrupt\n");
812		return result;
813	}
814
815	/*
816	 * enable clock for the I2C peripheral (non fatal),
817	 * keep a reference upon successful allocation
818	 */
819	clk = devm_clk_get_optional(&op->dev, NULL);
820	if (IS_ERR(clk))
 
821		return PTR_ERR(clk);
822
823	err = clk_prepare_enable(clk);
824	if (err) {
825		dev_err(&op->dev, "failed to enable clock\n");
826		return err;
827	}
828
829	i2c->clk_per = clk;
830
831	if (of_property_read_bool(op->dev.of_node, "fsl,preserve-clocking")) {
832		clock = MPC_I2C_CLOCK_PRESERVE;
833	} else {
834		prop = of_get_property(op->dev.of_node, "clock-frequency",
835					&plen);
836		if (prop && plen == sizeof(u32))
837			clock = *prop;
838	}
839
840	data = device_get_match_data(&op->dev);
841	if (data) {
842		data->setup(op->dev.of_node, i2c, clock);
843	} else {
844		/* Backwards compatibility */
845		if (of_get_property(op->dev.of_node, "dfsrr", NULL))
846			mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock);
847	}
848
849	prop = of_get_property(op->dev.of_node, "fsl,timeout", &plen);
850	if (prop && plen == sizeof(u32)) {
851		mpc_ops.timeout = *prop * HZ / 1000000;
 
 
 
 
 
 
 
 
 
 
 
852		if (mpc_ops.timeout < 5)
853			mpc_ops.timeout = 5;
 
 
854	}
 
855	dev_info(i2c->dev, "timeout %u us\n", mpc_ops.timeout * 1000000 / HZ);
856
857	if (of_property_read_bool(op->dev.of_node, "fsl,i2c-erratum-a004447"))
858		i2c->has_errata_A004447 = true;
859
860	i2c->adap = mpc_ops;
861	scnprintf(i2c->adap.name, sizeof(i2c->adap.name),
862		  "MPC adapter (%s)", of_node_full_name(op->dev.of_node));
863	i2c->adap.dev.parent = &op->dev;
864	i2c->adap.nr = op->id;
865	i2c->adap.dev.of_node = of_node_get(op->dev.of_node);
866	i2c->adap.bus_recovery_info = &fsl_i2c_recovery_info;
867	platform_set_drvdata(op, i2c);
868	i2c_set_adapdata(&i2c->adap, i2c);
869
870	result = i2c_add_numbered_adapter(&i2c->adap);
871	if (result)
872		goto fail_add;
873
874	return 0;
875
876 fail_add:
877	clk_disable_unprepare(i2c->clk_per);
878
879	return result;
880};
881
882static int fsl_i2c_remove(struct platform_device *op)
883{
884	struct mpc_i2c *i2c = platform_get_drvdata(op);
885
886	i2c_del_adapter(&i2c->adap);
887
888	clk_disable_unprepare(i2c->clk_per);
889
890	return 0;
891};
892
893static int __maybe_unused mpc_i2c_suspend(struct device *dev)
894{
895	struct mpc_i2c *i2c = dev_get_drvdata(dev);
896
897	i2c->fdr = readb(i2c->base + MPC_I2C_FDR);
898	i2c->dfsrr = readb(i2c->base + MPC_I2C_DFSRR);
899
900	return 0;
901}
902
903static int __maybe_unused mpc_i2c_resume(struct device *dev)
904{
905	struct mpc_i2c *i2c = dev_get_drvdata(dev);
906
907	writeb(i2c->fdr, i2c->base + MPC_I2C_FDR);
908	writeb(i2c->dfsrr, i2c->base + MPC_I2C_DFSRR);
909
910	return 0;
911}
912static SIMPLE_DEV_PM_OPS(mpc_i2c_pm_ops, mpc_i2c_suspend, mpc_i2c_resume);
913
914static const struct mpc_i2c_data mpc_i2c_data_512x = {
915	.setup = mpc_i2c_setup_512x,
916};
917
918static const struct mpc_i2c_data mpc_i2c_data_52xx = {
919	.setup = mpc_i2c_setup_52xx,
920};
921
922static const struct mpc_i2c_data mpc_i2c_data_8313 = {
923	.setup = mpc_i2c_setup_8xxx,
924};
925
926static const struct mpc_i2c_data mpc_i2c_data_8543 = {
927	.setup = mpc_i2c_setup_8xxx,
928};
929
930static const struct mpc_i2c_data mpc_i2c_data_8544 = {
931	.setup = mpc_i2c_setup_8xxx,
932};
933
934static const struct of_device_id mpc_i2c_of_match[] = {
935	{.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
936	{.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, },
937	{.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
938	{.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, },
939	{.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, },
940	{.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, },
941	{.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, },
942	/* Backward compatibility */
943	{.compatible = "fsl-i2c", },
944	{},
945};
946MODULE_DEVICE_TABLE(of, mpc_i2c_of_match);
947
948/* Structure for a device driver */
949static struct platform_driver mpc_i2c_driver = {
950	.probe		= fsl_i2c_probe,
951	.remove		= fsl_i2c_remove,
952	.driver = {
953		.name = DRV_NAME,
954		.of_match_table = mpc_i2c_of_match,
955		.pm = &mpc_i2c_pm_ops,
956	},
957};
958
959module_platform_driver(mpc_i2c_driver);
960
961MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>");
962MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and "
963		   "MPC824x/83xx/85xx/86xx/512x/52xx processors");
964MODULE_LICENSE("GPL");