[people/ms/u-boot.git] / cpu / mpc5xxx / i2c.c

/*
 * (C) Copyright 2003
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * See file CREDITS for list of people who contributed to this
 * project.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 */

#include <common.h>

#ifdef CONFIG_HARD_I2C

#include <mpc5xxx.h>
#include <i2c.h>

#if (CFG_I2C_MODULE == 2)
#define I2C_BASE	MPC5XXX_I2C2
#elif (CFG_I2C_MODULE == 1)
#define I2C_BASE	MPC5XXX_I2C1
#else
#error CFG_I2C_MODULE is not properly configured
#endif

#define I2C_TIMEOUT	100
#define I2C_RETRIES	3

struct mpc5xxx_i2c_tap {
	int scl2tap;
	int tap2tap;
};

static int  mpc_reg_in    (volatile u32 *reg);
static void mpc_reg_out   (volatile u32 *reg, int val, int mask);
static int  wait_for_bb   (void);
static int  wait_for_pin  (int *status);
static int  do_address    (uchar chip, char rdwr_flag);
static int  send_bytes    (uchar chip, char *buf, int len);
static int  receive_bytes (uchar chip, char *buf, int len);
static int  mpc_get_fdr   (int);

static int mpc_reg_in(volatile u32 *reg)
{
	return *reg >> 24;
	__asm__ __volatile__ ("eieio");
}

static void mpc_reg_out(volatile u32 *reg, int val, int mask)
{
	int tmp;

	if (!mask) {
		*reg = val << 24;
	} else {
		tmp = mpc_reg_in(reg);
		*reg = ((tmp & ~mask) | (val & mask)) << 24;
	}
	__asm__ __volatile__ ("eieio");

	return;
}

static int wait_for_bb(void)
{
	struct mpc5xxx_i2c *regs    = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 timeout = I2C_TIMEOUT;
	int                 status;

	status = mpc_reg_in(&regs->msr);

	while (timeout-- && (status & I2C_BB)) {
#if 1
		volatile int temp;
		mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
		temp = mpc_reg_in(&regs->mdr);
		mpc_reg_out(&regs->mcr, 0, I2C_STA);
		mpc_reg_out(&regs->mcr, 0, 0);
		mpc_reg_out(&regs->mcr, I2C_EN, 0);
#endif
		udelay(1000);
		status = mpc_reg_in(&regs->msr);
	}

	return (status & I2C_BB);
}

static int wait_for_pin(int *status)
{
	struct mpc5xxx_i2c *regs    = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 timeout = I2C_TIMEOUT;

	*status = mpc_reg_in(&regs->msr);

	while (timeout-- && !(*status & I2C_IF)) {
		udelay(1000);
		*status = mpc_reg_in(&regs->msr);
	}

	if (!(*status & I2C_IF)) {
		return -1;
	}

	mpc_reg_out(&regs->msr, 0, I2C_IF);

	return 0;
}

static int do_address(uchar chip, char rdwr_flag)
{
	struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 status;

	chip <<= 1;

	if (rdwr_flag) {
		chip |= 1;
	}

	mpc_reg_out(&regs->mcr, I2C_TX, I2C_TX);
	mpc_reg_out(&regs->mdr, chip, 0);

	if (wait_for_pin(&status)) {
		return -2;
	}

	if (status & I2C_RXAK) {
		return -3;
	}

	return 0;
}

static int send_bytes(uchar chip, char *buf, int len)
{
	struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 wrcount;
	int                 status;

	for (wrcount = 0; wrcount < len; ++wrcount) {

		mpc_reg_out(&regs->mdr, buf[wrcount], 0);

		if (wait_for_pin(&status)) {
			break;
		}

		if (status & I2C_RXAK) {
			break;
		}

	}

	return !(wrcount == len);
}

static int receive_bytes(uchar chip, char *buf, int len)
{
	struct mpc5xxx_i2c *regs    = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 dummy   = 1;
	int                 rdcount = 0;
	int                 status;
	int                 i;

	mpc_reg_out(&regs->mcr, 0, I2C_TX);

	for (i = 0; i < len; ++i) {
		buf[rdcount] = mpc_reg_in(&regs->mdr);

		if (dummy) {
			dummy = 0;
		} else {
			rdcount++;
		}


		if (wait_for_pin(&status)) {
			return -4;
		}
	}

	mpc_reg_out(&regs->mcr, I2C_TXAK, I2C_TXAK);
	buf[rdcount++] = mpc_reg_in(&regs->mdr);

	if (wait_for_pin(&status)) {
		return -5;
	}

	mpc_reg_out(&regs->mcr, 0, I2C_TXAK);

	return 0;
}

/**************** I2C API ****************/

void i2c_init(int speed, int saddr)
{
	struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE;

	mpc_reg_out(&regs->mcr, 0, 0);
	mpc_reg_out(&regs->madr, saddr << 1, 0);

	/* Set clock
	 */
	mpc_reg_out(&regs->mfdr, mpc_get_fdr(speed), 0);

	/* Enable module
	 */
	mpc_reg_out(&regs->mcr, I2C_EN, I2C_INIT_MASK);
	mpc_reg_out(&regs->msr, 0, I2C_IF);

	return;
}

static int mpc_get_fdr(int speed)
{
	DECLARE_GLOBAL_DATA_PTR;
	static int fdr = -1;
	static int best_speed = 0;

	if (fdr == -1) {
		ulong ipb, scl;
		ulong bestmatch = 0xffffffffUL;
		int best_i = 0, best_j = 0, i, j;
		int SCL_Tap[] = { 9, 10, 12, 15, 5, 6, 7, 8};
		struct mpc5xxx_i2c_tap scltap[] = {
			{4, 1},
			{4, 2},
			{6, 4},
			{6, 8},
			{14, 16},
			{30, 32},
			{62, 64},
			{126, 128}
		};

		ipb = gd->ipb_clk;
		for (i = 7; i >= 0; i--) {
			for (j = 7; j >= 0; j--) {
				scl = 2 * (scltap[j].scl2tap +
					(SCL_Tap[i] - 1) * scltap[j].tap2tap + 2);
				if (ipb <= speed*scl) {
					if ((speed*scl - ipb) < bestmatch) {
						bestmatch = speed*scl - ipb;
						best_i = i;
						best_j = j;
						best_speed = ipb/scl;
					}
				}
			}
		}
		fdr = (best_i & 3) | ((best_i & 4) << 3) | (best_j << 2);
		printf("%d kHz, ", best_speed / 1000);
	}

	return fdr;
}

int i2c_probe(uchar chip)
{
	struct mpc5xxx_i2c *regs = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 i;

	for (i = 0; i < I2C_RETRIES; i++) {
		mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);

		if (! do_address(chip, 0)) {
			mpc_reg_out(&regs->mcr, 0, I2C_STA);
			break;
		}

		mpc_reg_out(&regs->mcr, 0, I2C_STA);
		udelay(500);
	}

	return (i == I2C_RETRIES);
}

int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
{
	uchar                xaddr[4];
	struct mpc5xxx_i2c * regs        = (struct mpc5xxx_i2c *)I2C_BASE;
	int                  ret         = -1;

	xaddr[0] = (addr >> 24) & 0xFF;
	xaddr[1] = (addr >> 16) & 0xFF;
	xaddr[2] = (addr >>  8) & 0xFF;
	xaddr[3] =  addr	& 0xFF;

	if (wait_for_bb()) {
		printf("i2c_read: bus is busy\n");
		goto Done;
	}

	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
	if (do_address(chip, 0)) {
		printf("i2c_read: failed to address chip\n");
		goto Done;
	}

	if (send_bytes(chip, &xaddr[4-alen], alen)) {
		printf("i2c_read: send_bytes failed\n");
		goto Done;
	}

	mpc_reg_out(&regs->mcr, I2C_RSTA, I2C_RSTA);
	if (do_address(chip, 1)) {
		printf("i2c_read: failed to address chip\n");
		goto Done;
	}

	if (receive_bytes(chip, buf, len)) {
		printf("i2c_read: receive_bytes failed\n");
		goto Done;
	}

	ret = 0;
Done:
	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	return ret;
}

int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
{
	uchar               xaddr[4];
	struct mpc5xxx_i2c *regs        = (struct mpc5xxx_i2c *)I2C_BASE;
	int                 ret         = -1;

	xaddr[0] = (addr >> 24) & 0xFF;
	xaddr[1] = (addr >> 16) & 0xFF;
	xaddr[2] = (addr >>  8) & 0xFF;
	xaddr[3] =  addr	& 0xFF;

	if (wait_for_bb()) {
		printf("i2c_write: bus is busy\n");
		goto Done;
	}

	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
	if (do_address(chip, 0)) {
		printf("i2c_write: failed to address chip\n");
		goto Done;
	}

	if (send_bytes(chip, &xaddr[4-alen], alen)) {
		printf("i2c_write: send_bytes failed\n");
		goto Done;
	}

	if (send_bytes(chip, buf, len)) {
		printf("i2c_write: send_bytes failed\n");
		goto Done;
	}

	ret = 0;
Done:
	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	return ret;
}

uchar i2c_reg_read(uchar chip, uchar reg)
{
	char buf;

	i2c_read(chip, reg, 1, &buf, 1);

	return buf;
}

void i2c_reg_write(uchar chip, uchar reg, uchar val)
{
	i2c_write(chip, reg, 1, &val, 1);

	return;
}

#endif	/* CONFIG_HARD_I2C */
Commit	Line	Data
531716e1 WD	1	/*
	2	* (C) Copyright 2003
	3	* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
	4	*
	5	* See file CREDITS for list of people who contributed to this
	6	* project.
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License as
	10	* published by the Free Software Foundation; either version 2 of
	11	* the License, or (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	21	* MA 02111-1307 USA
	22	*/
	23
	24	#include <common.h>
	25
	26	#ifdef CONFIG_HARD_I2C
	27
	28	#include <mpc5xxx.h>
	29	#include <i2c.h>
	30
ab209d51	31	#if (CFG_I2C_MODULE == 2)
531716e1	32	#define I2C_BASE MPC5XXX_I2C2
ab209d51	33	#elif (CFG_I2C_MODULE == 1)
531716e1	34	#define I2C_BASE MPC5XXX_I2C1
ab209d51	35	#else
ab209d51	36	#error CFG_I2C_MODULE is not properly configured
531716e1 WD	37	#endif
	38
	39	#define I2C_TIMEOUT 100
	40	#define I2C_RETRIES 3
	41
ab209d51	42	struct mpc5xxx_i2c_tap {
	43	int scl2tap;
	44	int tap2tap;
	45	};
	46
531716e1 WD	47	static int mpc_reg_in (volatile u32 *reg);
	48	static void mpc_reg_out (volatile u32 *reg, int val, int mask);
	49	static int wait_for_bb (void);
	50	static int wait_for_pin (int *status);
	51	static int do_address (uchar chip, char rdwr_flag);
	52	static int send_bytes (uchar chip, char *buf, int len);
	53	static int receive_bytes (uchar chip, char *buf, int len);
ab209d51	54	static int mpc_get_fdr (int);
531716e1 WD	55
	56	static int mpc_reg_in(volatile u32 *reg)
	57	{
	58	return *reg >> 24;
	59	__asm__ __volatile__ ("eieio");
	60	}
	61
	62	static void mpc_reg_out(volatile u32 *reg, int val, int mask)
	63	{
	64	int tmp;
	65
	66	if (!mask) {
	67	*reg = val << 24;
	68	} else {
	69	tmp = mpc_reg_in(reg);
	70	*reg = ((tmp & ~mask) \| (val & mask)) << 24;
	71	}
	72	__asm__ __volatile__ ("eieio");
	73
	74	return;
	75	}
	76
	77	static int wait_for_bb(void)
	78	{
	79	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
	80	int timeout = I2C_TIMEOUT;
	81	int status;
	82
	83	status = mpc_reg_in(&regs->msr);
	84
	85	while (timeout-- && (status & I2C_BB)) {
	86	#if 1
	87	volatile int temp;
	88	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
	89	temp = mpc_reg_in(&regs->mdr);
	90	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	91	mpc_reg_out(&regs->mcr, 0, 0);
	92	mpc_reg_out(&regs->mcr, I2C_EN, 0);
	93	#endif
	94	udelay(1000);
	95	status = mpc_reg_in(&regs->msr);
	96	}
	97
	98	return (status & I2C_BB);
	99	}
	100
	101	static int wait_for_pin(int *status)
	102	{
	103	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
	104	int timeout = I2C_TIMEOUT;
	105
	106	*status = mpc_reg_in(&regs->msr);
	107
	108	while (timeout-- && !(*status & I2C_IF)) {
	109	udelay(1000);
	110	*status = mpc_reg_in(&regs->msr);
	111	}
	112
	113	if (!(*status & I2C_IF)) {
	114	return -1;
	115	}
	116
	117	mpc_reg_out(&regs->msr, 0, I2C_IF);
	118
119	return 0;
120	}
121
122	static int do_address(uchar chip, char rdwr_flag)
123	{
124	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
125	int status;
126
127	chip <<= 1;
128
129	if (rdwr_flag) {
130	chip \|= 1;
131	}
132
133	mpc_reg_out(&regs->mcr, I2C_TX, I2C_TX);
134	mpc_reg_out(&regs->mdr, chip, 0);
135
42d1f039 WD	136	if (wait_for_pin(&status)) {
	137	return -2;
	138	}
531716e1	139
42d1f039 WD	140	if (status & I2C_RXAK) {
	141	return -3;
	142	}
531716e1 WD	143
	144	return 0;
	145	}
	146
	147	static int send_bytes(uchar chip, char *buf, int len)
	148	{
	149	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
	150	int wrcount;
	151	int status;
	152
	153	for (wrcount = 0; wrcount < len; ++wrcount) {
	154
	155	mpc_reg_out(&regs->mdr, buf[wrcount], 0);
	156
	157	if (wait_for_pin(&status)) {
	158	break;
	159	}
	160
	161	if (status & I2C_RXAK) {
	162	break;
	163	}
	164
	165	}
	166
	167	return !(wrcount == len);
	168	}
	169
	170	static int receive_bytes(uchar chip, char *buf, int len)
	171	{
	172	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
	173	int dummy = 1;
	174	int rdcount = 0;
	175	int status;
	176	int i;
	177
	178	mpc_reg_out(&regs->mcr, 0, I2C_TX);
	179
	180	for (i = 0; i < len; ++i) {
	181	buf[rdcount] = mpc_reg_in(&regs->mdr);
	182
	183	if (dummy) {
	184	dummy = 0;
	185	} else {
	186	rdcount++;
	187	}
	188
	189
	190	if (wait_for_pin(&status)) {
	191	return -4;
	192	}
	193	}
	194
	195	mpc_reg_out(&regs->mcr, I2C_TXAK, I2C_TXAK);
	196	buf[rdcount++] = mpc_reg_in(&regs->mdr);
	197
	198	if (wait_for_pin(&status)) {
	199	return -5;
	200	}
	201
	202	mpc_reg_out(&regs->mcr, 0, I2C_TXAK);
	203
	204	return 0;
	205	}
	206
207	/************** I2C API **************/
208
209	void i2c_init(int speed, int saddr)
210	{
211	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
212
213	mpc_reg_out(&regs->mcr, 0, 0);
214	mpc_reg_out(&regs->madr, saddr << 1, 0);
215
216	/* Set clock
217	*/
ab209d51	218	mpc_reg_out(&regs->mfdr, mpc_get_fdr(speed), 0);
531716e1 WD	219
	220	/* Enable module
	221	*/
	222	mpc_reg_out(&regs->mcr, I2C_EN, I2C_INIT_MASK);
	223	mpc_reg_out(&regs->msr, 0, I2C_IF);
	224
	225	return;
	226	}
	227
ab209d51	228	static int mpc_get_fdr(int speed)
	229	{
	230	DECLARE_GLOBAL_DATA_PTR;
	231	static int fdr = -1;
	232	static int best_speed = 0;
	233
	234	if (fdr == -1) {
	235	ulong ipb, scl;
	236	ulong bestmatch = 0xffffffffUL;
	237	int best_i = 0, best_j = 0, i, j;
	238	int SCL_Tap[] = { 9, 10, 12, 15, 5, 6, 7, 8};
	239	struct mpc5xxx_i2c_tap scltap[] = {
	240	{4, 1},
	241	{4, 2},
	242	{6, 4},
	243	{6, 8},
	244	{14, 16},
	245	{30, 32},
	246	{62, 64},
	247	{126, 128}
	248	};
	249
	250	ipb = gd->ipb_clk;
	251	for (i = 7; i >= 0; i--) {
	252	for (j = 7; j >= 0; j--) {
42d1f039	253	scl = 2 * (scltap[j].scl2tap +
ab209d51	254	(SCL_Tap[i] - 1) * scltap[j].tap2tap + 2);
	255	if (ipb <= speed*scl) {
	256	if ((speed*scl - ipb) < bestmatch) {
	257	bestmatch = speed*scl - ipb;
	258	best_i = i;
	259	best_j = j;
	260	best_speed = ipb/scl;
	261	}
	262	}
	263	}
	264	}
	265	fdr = (best_i & 3) \| ((best_i & 4) << 3) \| (best_j << 2);
	266	printf("%d kHz, ", best_speed / 1000);
	267	}
	268
	269	return fdr;
	270	}
	271
531716e1 WD	272	int i2c_probe(uchar chip)
	273	{
	274	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
	275	int i;
	276
	277	for (i = 0; i < I2C_RETRIES; i++) {
	278	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
	279
	280	if (! do_address(chip, 0)) {
	281	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	282	break;
	283	}
	284
	285	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	286	udelay(500);
	287	}
	288
	289	return (i == I2C_RETRIES);
	290	}
	291
	292	int i2c_read(uchar chip, uint addr, int alen, uchar *buf, int len)
	293	{
	294	uchar xaddr[4];
	295	struct mpc5xxx_i2c * regs = (struct mpc5xxx_i2c *)I2C_BASE;
	296	int ret = -1;
	297
	298	xaddr[0] = (addr >> 24) & 0xFF;
	299	xaddr[1] = (addr >> 16) & 0xFF;
	300	xaddr[2] = (addr >> 8) & 0xFF;
	301	xaddr[3] = addr & 0xFF;
	302
	303	if (wait_for_bb()) {
	304	printf("i2c_read: bus is busy\n");
	305	goto Done;
	306	}
	307
	308	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
	309	if (do_address(chip, 0)) {
	310	printf("i2c_read: failed to address chip\n");
	311	goto Done;
	312	}
	313
	314	if (send_bytes(chip, &xaddr[4-alen], alen)) {
	315	printf("i2c_read: send_bytes failed\n");
	316	goto Done;
	317	}
	318
	319	mpc_reg_out(&regs->mcr, I2C_RSTA, I2C_RSTA);
	320	if (do_address(chip, 1)) {
	321	printf("i2c_read: failed to address chip\n");
	322	goto Done;
	323	}
	324
	325	if (receive_bytes(chip, buf, len)) {
	326	printf("i2c_read: receive_bytes failed\n");
	327	goto Done;
	328	}
	329
	330	ret = 0;
	331	Done:
	332	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	333	return ret;
	334	}
	335
336	int i2c_write(uchar chip, uint addr, int alen, uchar *buf, int len)
337	{
338	uchar xaddr[4];
339	struct mpc5xxx_i2c regs = (struct mpc5xxx_i2c )I2C_BASE;
340	int ret = -1;
341
342	xaddr[0] = (addr >> 24) & 0xFF;
343	xaddr[1] = (addr >> 16) & 0xFF;
344	xaddr[2] = (addr >> 8) & 0xFF;
345	xaddr[3] = addr & 0xFF;
346
42d1f039	347	if (wait_for_bb()) {
531716e1 WD	348	printf("i2c_write: bus is busy\n");
	349	goto Done;
	350	}
	351
42d1f039 WD	352	mpc_reg_out(&regs->mcr, I2C_STA, I2C_STA);
42d1f039 WD	353	if (do_address(chip, 0)) {
531716e1 WD	354	printf("i2c_write: failed to address chip\n");
	355	goto Done;
	356	}
	357
	358	if (send_bytes(chip, &xaddr[4-alen], alen)) {
	359	printf("i2c_write: send_bytes failed\n");
	360	goto Done;
	361	}
	362
	363	if (send_bytes(chip, buf, len)) {
	364	printf("i2c_write: send_bytes failed\n");
	365	goto Done;
	366	}
	367
	368	ret = 0;
	369	Done:
	370	mpc_reg_out(&regs->mcr, 0, I2C_STA);
	371	return ret;
	372	}
	373
	374	uchar i2c_reg_read(uchar chip, uchar reg)
	375	{
	376	char buf;
	377
	378	i2c_read(chip, reg, 1, &buf, 1);
	379
	380	return buf;
	381	}
	382
	383	void i2c_reg_write(uchar chip, uchar reg, uchar val)
	384	{
	385	i2c_write(chip, reg, 1, &val, 1);
	386
	387	return;
	388	}
	389
	390	#endif /* CONFIG_HARD_I2C */