drivers/media/dvb-frontends/dibx000_common.c - kernel/quantenna - Git at Google

 #include <linux/i2c.h>
 #include <linux/mutex.h>
 #include <linux/module.h>

 #include "dibx000_common.h"

 static int debug;
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");

 #define dprintk(args...) do { if (debug) { printk(KERN_DEBUG "DiBX000: "); printk(args); printk("\n"); } } while (0)

 static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
 {
 	int ret;

 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 		dprintk("could not acquire lock");
 		return -EINVAL;
 	}

 	mst->i2c_write_buffer[0] = (reg >> 8) & 0xff;
 	mst->i2c_write_buffer[1] = reg & 0xff;
 	mst->i2c_write_buffer[2] = (val >> 8) & 0xff;
 	mst->i2c_write_buffer[3] = val & 0xff;

 	memset(mst->msg, 0, sizeof(struct i2c_msg));
 	mst->msg[0].addr = mst->i2c_addr;
 	mst->msg[0].flags = 0;
 	mst->msg[0].buf = mst->i2c_write_buffer;
 	mst->msg[0].len = 4;

 	ret = i2c_transfer(mst->i2c_adap, mst->msg, 1) != 1 ? -EREMOTEIO : 0;
 	mutex_unlock(&mst->i2c_buffer_lock);

 	return ret;
 }

 static u16 dibx000_read_word(struct dibx000_i2c_master *mst, u16 reg)
 {
 	u16 ret;

 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 		dprintk("could not acquire lock");
 		return 0;
 	}

 	mst->i2c_write_buffer[0] = reg >> 8;
 	mst->i2c_write_buffer[1] = reg & 0xff;

 	memset(mst->msg, 0, 2 * sizeof(struct i2c_msg));
 	mst->msg[0].addr = mst->i2c_addr;
 	mst->msg[0].flags = 0;
 	mst->msg[0].buf = mst->i2c_write_buffer;
 	mst->msg[0].len = 2;
 	mst->msg[1].addr = mst->i2c_addr;
 	mst->msg[1].flags = I2C_M_RD;
 	mst->msg[1].buf = mst->i2c_read_buffer;
 	mst->msg[1].len = 2;

 	if (i2c_transfer(mst->i2c_adap, mst->msg, 2) != 2)
 		dprintk("i2c read error on %d", reg);

 	ret = (mst->i2c_read_buffer[0] << 8) | mst->i2c_read_buffer[1];
 	mutex_unlock(&mst->i2c_buffer_lock);

 	return ret;
 }

 static int dibx000_is_i2c_done(struct dibx000_i2c_master *mst)
 {
 	int i = 100;
 	u16 status;

 	while (((status = dibx000_read_word(mst, mst->base_reg + 2)) & 0x0100) == 0 && --i > 0)
 		;

 	/* i2c timed out */
 	if (i == 0)
 		return -EREMOTEIO;

 	/* no acknowledge */
 	if ((status & 0x0080) == 0)
 		return -EREMOTEIO;

 	return 0;
 }

 static int dibx000_master_i2c_write(struct dibx000_i2c_master *mst, struct i2c_msg *msg, u8 stop)
 {
 	u16 data;
 	u16 da;
 	u16 i;
 	u16 txlen = msg->len, len;
 	const u8 *b = msg->buf;

 	while (txlen) {
 		dibx000_read_word(mst, mst->base_reg + 2);

 		len = txlen > 8 ? 8 : txlen;
 		for (i = 0; i < len; i += 2) {
 			data = *b++ << 8;
 			if (i+1 < len)
 				data |= *b++;
 			dibx000_write_word(mst, mst->base_reg, data);
 		}
 		da = (((u8) (msg->addr))  << 9) |
 			(1           << 8) |
 			(1           << 7) |
 			(0           << 6) |
 			(0           << 5) |
 			((len & 0x7) << 2) |
 			(0           << 1) |
 			(0           << 0);

 		if (txlen == msg->len)
 			da |= 1 << 5; /* start */

 		if (txlen-len == 0 && stop)
 			da |= 1 << 6; /* stop */

 		dibx000_write_word(mst, mst->base_reg+1, da);

 		if (dibx000_is_i2c_done(mst) != 0)
 			return -EREMOTEIO;
 		txlen -= len;
 	}

 	return 0;
 }

 static int dibx000_master_i2c_read(struct dibx000_i2c_master *mst, struct i2c_msg *msg)
 {
 	u16 da;
 	u8 *b = msg->buf;
 	u16 rxlen = msg->len, len;

 	while (rxlen) {
 		len = rxlen > 8 ? 8 : rxlen;
 		da = (((u8) (msg->addr)) << 9) |
 			(1           << 8) |
 			(1           << 7) |
 			(0           << 6) |
 			(0           << 5) |
 			((len & 0x7) << 2) |
 			(1           << 1) |
 			(0           << 0);

 		if (rxlen == msg->len)
 			da |= 1 << 5; /* start */

 		if (rxlen-len == 0)
 			da |= 1 << 6; /* stop */
 		dibx000_write_word(mst, mst->base_reg+1, da);

 		if (dibx000_is_i2c_done(mst) != 0)
 			return -EREMOTEIO;

 		rxlen -= len;

 		while (len) {
 			da = dibx000_read_word(mst, mst->base_reg);
 			*b++ = (da >> 8) & 0xff;
 			len--;
 			if (len >= 1) {
 				*b++ =  da   & 0xff;
 				len--;
 			}
 		}
 	}

 	return 0;
 }

 int dibx000_i2c_set_speed(struct i2c_adapter *i2c_adap, u16 speed)
 {
 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);

 	if (mst->device_rev < DIB7000MC && speed < 235)
 		speed = 235;
 	return dibx000_write_word(mst, mst->base_reg + 3, (u16)(60000 / speed));

 }
 EXPORT_SYMBOL(dibx000_i2c_set_speed);

 static u32 dibx000_i2c_func(struct i2c_adapter *adapter)
 {
 	return I2C_FUNC_I2C;
 }

 static int dibx000_i2c_select_interface(struct dibx000_i2c_master *mst,
 					enum dibx000_i2c_interface intf)
 {
 	if (mst->device_rev > DIB3000MC && mst->selected_interface != intf) {
 		dprintk("selecting interface: %d", intf);
 		mst->selected_interface = intf;
 		return dibx000_write_word(mst, mst->base_reg + 4, intf);
 	}
 	return 0;
 }

 static int dibx000_i2c_master_xfer_gpio12(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
 {
 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 	int msg_index;
 	int ret = 0;

 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_1_2);
 	for (msg_index = 0; msg_index < num; msg_index++) {
 		if (msg[msg_index].flags & I2C_M_RD) {
 			ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
 			if (ret != 0)
 				return 0;
 		} else {
 			ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
 			if (ret != 0)
 				return 0;
 		}
 	}

 	return num;
 }

 static int dibx000_i2c_master_xfer_gpio34(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
 {
 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 	int msg_index;
 	int ret = 0;

 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_3_4);
 	for (msg_index = 0; msg_index < num; msg_index++) {
 		if (msg[msg_index].flags & I2C_M_RD) {
 			ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
 			if (ret != 0)
 				return 0;
 		} else {
 			ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
 			if (ret != 0)
 				return 0;
 		}
 	}

 	return num;
 }

 static struct i2c_algorithm dibx000_i2c_master_gpio12_xfer_algo = {
 	.master_xfer = dibx000_i2c_master_xfer_gpio12,
 	.functionality = dibx000_i2c_func,
 };

 static struct i2c_algorithm dibx000_i2c_master_gpio34_xfer_algo = {
 	.master_xfer = dibx000_i2c_master_xfer_gpio34,
 	.functionality = dibx000_i2c_func,
 };

 static int dibx000_i2c_gate_ctrl(struct dibx000_i2c_master *mst, u8 tx[4],
 				 u8 addr, int onoff)
 {
 	u16 val;


 	if (onoff)
 		val = addr << 8;	// bit 7 = use master or not, if 0, the gate is open
 	else
 		val = 1 << 7;

 	if (mst->device_rev > DIB7000)
 		val <<= 1;

 	tx[0] = (((mst->base_reg + 1) >> 8) & 0xff);
 	tx[1] = ((mst->base_reg + 1) & 0xff);
 	tx[2] = val >> 8;
 	tx[3] = val & 0xff;

 	return 0;
 }

 static int dibx000_i2c_gated_gpio67_xfer(struct i2c_adapter *i2c_adap,
 					struct i2c_msg msg[], int num)
 {
 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 	int ret;

 	if (num > 32) {
 		dprintk("%s: too much I2C message to be transmitted (%i).\
 				Maximum is 32", __func__, num);
 		return -ENOMEM;
 	}

 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_6_7);

 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 		dprintk("could not acquire lock");
 		return -EINVAL;
 	}

 	memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));

 	/* open the gate */
 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
 	mst->msg[0].addr = mst->i2c_addr;
 	mst->msg[0].buf = &mst->i2c_write_buffer[0];
 	mst->msg[0].len = 4;

 	memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);

 	/* close the gate */
 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
 	mst->msg[num + 1].addr = mst->i2c_addr;
 	mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
 	mst->msg[num + 1].len = 4;

 	ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
 			num : -EIO);

 	mutex_unlock(&mst->i2c_buffer_lock);
 	return ret;
 }

 static struct i2c_algorithm dibx000_i2c_gated_gpio67_algo = {
 	.master_xfer = dibx000_i2c_gated_gpio67_xfer,
 	.functionality = dibx000_i2c_func,
 };

 static int dibx000_i2c_gated_tuner_xfer(struct i2c_adapter *i2c_adap,
 					struct i2c_msg msg[], int num)
 {
 	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
 	int ret;

 	if (num > 32) {
 		dprintk("%s: too much I2C message to be transmitted (%i).\
 				Maximum is 32", __func__, num);
 		return -ENOMEM;
 	}

 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);

 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 		dprintk("could not acquire lock");
 		return -EINVAL;
 	}
 	memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));

 	/* open the gate */
 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
 	mst->msg[0].addr = mst->i2c_addr;
 	mst->msg[0].buf = &mst->i2c_write_buffer[0];
 	mst->msg[0].len = 4;

 	memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);

 	/* close the gate */
 	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
 	mst->msg[num + 1].addr = mst->i2c_addr;
 	mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
 	mst->msg[num + 1].len = 4;

 	ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
 			num : -EIO);
 	mutex_unlock(&mst->i2c_buffer_lock);
 	return ret;
 }

 static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {
 	.master_xfer = dibx000_i2c_gated_tuner_xfer,
 	.functionality = dibx000_i2c_func,
 };

 struct i2c_adapter *dibx000_get_i2c_adapter(struct dibx000_i2c_master *mst,
 						enum dibx000_i2c_interface intf,
 						int gating)
 {
 	struct i2c_adapter *i2c = NULL;

 	switch (intf) {
 	case DIBX000_I2C_INTERFACE_TUNER:
 		if (gating)
 			i2c = &mst->gated_tuner_i2c_adap;
 		break;
 	case DIBX000_I2C_INTERFACE_GPIO_1_2:
 		if (!gating)
 			i2c = &mst->master_i2c_adap_gpio12;
 		break;
 	case DIBX000_I2C_INTERFACE_GPIO_3_4:
 		if (!gating)
 			i2c = &mst->master_i2c_adap_gpio34;
 		break;
 	case DIBX000_I2C_INTERFACE_GPIO_6_7:
 		if (gating)
 			i2c = &mst->master_i2c_adap_gpio67;
 		break;
 	default:
 		printk(KERN_ERR "DiBX000: incorrect I2C interface selected\n");
 		break;
 	}

 	return i2c;
 }

 EXPORT_SYMBOL(dibx000_get_i2c_adapter);

 void dibx000_reset_i2c_master(struct dibx000_i2c_master *mst)
 {
 	/* initialize the i2c-master by closing the gate */
 	u8 tx[4];
 	struct i2c_msg m = {.addr = mst->i2c_addr,.buf = tx,.len = 4 };

 	dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
 	i2c_transfer(mst->i2c_adap, &m, 1);
 	mst->selected_interface = 0xff;	// the first time force a select of the I2C
 	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
 }

 EXPORT_SYMBOL(dibx000_reset_i2c_master);

 static int i2c_adapter_init(struct i2c_adapter *i2c_adap,
 				struct i2c_algorithm *algo, const char *name,
 				struct dibx000_i2c_master *mst)
 {
 	strncpy(i2c_adap->name, name, sizeof(i2c_adap->name));
 	i2c_adap->algo = algo;
 	i2c_adap->algo_data = NULL;
 	i2c_set_adapdata(i2c_adap, mst);
 	if (i2c_add_adapter(i2c_adap) < 0)
 		return -ENODEV;
 	return 0;
 }

 int dibx000_init_i2c_master(struct dibx000_i2c_master *mst, u16 device_rev,
 				struct i2c_adapter *i2c_adap, u8 i2c_addr)
 {
 	int ret;

 	mutex_init(&mst->i2c_buffer_lock);
 	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
 		dprintk("could not acquire lock");
 		return -EINVAL;
 	}
 	memset(mst->msg, 0, sizeof(struct i2c_msg));
 	mst->msg[0].addr = i2c_addr >> 1;
 	mst->msg[0].flags = 0;
 	mst->msg[0].buf = mst->i2c_write_buffer;
 	mst->msg[0].len = 4;

 	mst->device_rev = device_rev;
 	mst->i2c_adap = i2c_adap;
 	mst->i2c_addr = i2c_addr >> 1;

 	if (device_rev == DIB7000P || device_rev == DIB8000)
 		mst->base_reg = 1024;
 	else
 		mst->base_reg = 768;

 	mst->gated_tuner_i2c_adap.dev.parent = mst->i2c_adap->dev.parent;
 	if (i2c_adapter_init
 			(&mst->gated_tuner_i2c_adap, &dibx000_i2c_gated_tuner_algo,
 			 "DiBX000 tuner I2C bus", mst) != 0)
 		printk(KERN_ERR
 				"DiBX000: could not initialize the tuner i2c_adapter\n");

 	mst->master_i2c_adap_gpio12.dev.parent = mst->i2c_adap->dev.parent;
 	if (i2c_adapter_init
 			(&mst->master_i2c_adap_gpio12, &dibx000_i2c_master_gpio12_xfer_algo,
 			 "DiBX000 master GPIO12 I2C bus", mst) != 0)
 		printk(KERN_ERR
 				"DiBX000: could not initialize the master i2c_adapter\n");

 	mst->master_i2c_adap_gpio34.dev.parent = mst->i2c_adap->dev.parent;
 	if (i2c_adapter_init
 			(&mst->master_i2c_adap_gpio34, &dibx000_i2c_master_gpio34_xfer_algo,
 			 "DiBX000 master GPIO34 I2C bus", mst) != 0)
 		printk(KERN_ERR
 				"DiBX000: could not initialize the master i2c_adapter\n");

 	mst->master_i2c_adap_gpio67.dev.parent = mst->i2c_adap->dev.parent;
 	if (i2c_adapter_init
 			(&mst->master_i2c_adap_gpio67, &dibx000_i2c_gated_gpio67_algo,
 			 "DiBX000 master GPIO67 I2C bus", mst) != 0)
 		printk(KERN_ERR
 				"DiBX000: could not initialize the master i2c_adapter\n");

 	/* initialize the i2c-master by closing the gate */
 	dibx000_i2c_gate_ctrl(mst, mst->i2c_write_buffer, 0, 0);

 	ret = (i2c_transfer(i2c_adap, mst->msg, 1) == 1);
 	mutex_unlock(&mst->i2c_buffer_lock);

 	return ret;
 }

 EXPORT_SYMBOL(dibx000_init_i2c_master);

 void dibx000_exit_i2c_master(struct dibx000_i2c_master *mst)
 {
 	i2c_del_adapter(&mst->gated_tuner_i2c_adap);
 	i2c_del_adapter(&mst->master_i2c_adap_gpio12);
 	i2c_del_adapter(&mst->master_i2c_adap_gpio34);
 	i2c_del_adapter(&mst->master_i2c_adap_gpio67);
 }
 EXPORT_SYMBOL(dibx000_exit_i2c_master);


 u32 systime(void)
 {
 	struct timespec t;

 	t = current_kernel_time();
 	return (t.tv_sec * 10000) + (t.tv_nsec / 100000);
 }
 EXPORT_SYMBOL(systime);

 MODULE_AUTHOR("Patrick Boettcher <patrick.boettcher@posteo.de>");
 MODULE_DESCRIPTION("Common function the DiBcom demodulator family");
 MODULE_LICENSE("GPL");
	#include <linux/i2c.h>
	#include <linux/mutex.h>
	#include <linux/module.h>

	#include "dibx000_common.h"

	static int debug;
	module_param(debug, int, 0644);
	MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");

	#define dprintk(args...) do { if (debug) { printk(KERN_DEBUG "DiBX000: "); printk(args); printk("\n"); } } while (0)

	static int dibx000_write_word(struct dibx000_i2c_master *mst, u16 reg, u16 val)
	{
	int ret;

	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
	dprintk("could not acquire lock");
	return -EINVAL;
	}

	mst->i2c_write_buffer[0] = (reg >> 8) & 0xff;
	mst->i2c_write_buffer[1] = reg & 0xff;
	mst->i2c_write_buffer[2] = (val >> 8) & 0xff;
	mst->i2c_write_buffer[3] = val & 0xff;

	memset(mst->msg, 0, sizeof(struct i2c_msg));
	mst->msg[0].addr = mst->i2c_addr;
	mst->msg[0].flags = 0;
	mst->msg[0].buf = mst->i2c_write_buffer;
	mst->msg[0].len = 4;

	ret = i2c_transfer(mst->i2c_adap, mst->msg, 1) != 1 ? -EREMOTEIO : 0;
	mutex_unlock(&mst->i2c_buffer_lock);

	return ret;
	}

	static u16 dibx000_read_word(struct dibx000_i2c_master *mst, u16 reg)
	{
	u16 ret;

	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
	dprintk("could not acquire lock");
	return 0;
	}

	mst->i2c_write_buffer[0] = reg >> 8;
	mst->i2c_write_buffer[1] = reg & 0xff;

	memset(mst->msg, 0, 2 * sizeof(struct i2c_msg));
	mst->msg[0].addr = mst->i2c_addr;
	mst->msg[0].flags = 0;
	mst->msg[0].buf = mst->i2c_write_buffer;
	mst->msg[0].len = 2;
	mst->msg[1].addr = mst->i2c_addr;
	mst->msg[1].flags = I2C_M_RD;
	mst->msg[1].buf = mst->i2c_read_buffer;
	mst->msg[1].len = 2;

	if (i2c_transfer(mst->i2c_adap, mst->msg, 2) != 2)
	dprintk("i2c read error on %d", reg);

	ret = (mst->i2c_read_buffer[0] << 8) \| mst->i2c_read_buffer[1];
	mutex_unlock(&mst->i2c_buffer_lock);

	return ret;
	}

	static int dibx000_is_i2c_done(struct dibx000_i2c_master *mst)
	{
	int i = 100;
	u16 status;

	while (((status = dibx000_read_word(mst, mst->base_reg + 2)) & 0x0100) == 0 && --i > 0)
	;

	/* i2c timed out */
	if (i == 0)
	return -EREMOTEIO;

	/* no acknowledge */
	if ((status & 0x0080) == 0)
	return -EREMOTEIO;

	return 0;
	}

	static int dibx000_master_i2c_write(struct dibx000_i2c_master mst, struct i2c_msg msg, u8 stop)
	{
	u16 data;
	u16 da;
	u16 i;
	u16 txlen = msg->len, len;
	const u8 *b = msg->buf;

	while (txlen) {
	dibx000_read_word(mst, mst->base_reg + 2);

	len = txlen > 8 ? 8 : txlen;
	for (i = 0; i < len; i += 2) {
	data = *b++ << 8;
	if (i+1 < len)
	data \|= *b++;
	dibx000_write_word(mst, mst->base_reg, data);
	}
	da = (((u8) (msg->addr)) << 9) \|
	(1 << 8) \|
	(1 << 7) \|
	(0 << 6) \|
	(0 << 5) \|
	((len & 0x7) << 2) \|
	(0 << 1) \|
	(0 << 0);

	if (txlen == msg->len)
	da \|= 1 << 5; /* start */

	if (txlen-len == 0 && stop)
	da \|= 1 << 6; /* stop */

	dibx000_write_word(mst, mst->base_reg+1, da);

	if (dibx000_is_i2c_done(mst) != 0)
	return -EREMOTEIO;
	txlen -= len;
	}

	return 0;
	}

	static int dibx000_master_i2c_read(struct dibx000_i2c_master mst, struct i2c_msg msg)
	{
	u16 da;
	u8 *b = msg->buf;
	u16 rxlen = msg->len, len;

	while (rxlen) {
	len = rxlen > 8 ? 8 : rxlen;
	da = (((u8) (msg->addr)) << 9) \|
	(1 << 8) \|
	(1 << 7) \|
	(0 << 6) \|
	(0 << 5) \|
	((len & 0x7) << 2) \|
	(1 << 1) \|
	(0 << 0);

	if (rxlen == msg->len)
	da \|= 1 << 5; /* start */

	if (rxlen-len == 0)
	da \|= 1 << 6; /* stop */
	dibx000_write_word(mst, mst->base_reg+1, da);

	if (dibx000_is_i2c_done(mst) != 0)
	return -EREMOTEIO;

	rxlen -= len;

	while (len) {
	da = dibx000_read_word(mst, mst->base_reg);
	*b++ = (da >> 8) & 0xff;
	len--;
	if (len >= 1) {
	*b++ = da & 0xff;
	len--;
	}
	}
	}

	return 0;
	}

	int dibx000_i2c_set_speed(struct i2c_adapter *i2c_adap, u16 speed)
	{
	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);

	if (mst->device_rev < DIB7000MC && speed < 235)
	speed = 235;
	return dibx000_write_word(mst, mst->base_reg + 3, (u16)(60000 / speed));

	}
	EXPORT_SYMBOL(dibx000_i2c_set_speed);

	static u32 dibx000_i2c_func(struct i2c_adapter *adapter)
	{
	return I2C_FUNC_I2C;
	}

	static int dibx000_i2c_select_interface(struct dibx000_i2c_master *mst,
	enum dibx000_i2c_interface intf)
	{
	if (mst->device_rev > DIB3000MC && mst->selected_interface != intf) {
	dprintk("selecting interface: %d", intf);
	mst->selected_interface = intf;
	return dibx000_write_word(mst, mst->base_reg + 4, intf);
	}
	return 0;
	}

	static int dibx000_i2c_master_xfer_gpio12(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
	{
	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
	int msg_index;
	int ret = 0;

	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_1_2);
	for (msg_index = 0; msg_index < num; msg_index++) {
	if (msg[msg_index].flags & I2C_M_RD) {
	ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
	if (ret != 0)
	return 0;
	} else {
	ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
	if (ret != 0)
	return 0;
	}
	}

	return num;
	}

	static int dibx000_i2c_master_xfer_gpio34(struct i2c_adapter *i2c_adap, struct i2c_msg msg[], int num)
	{
	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
	int msg_index;
	int ret = 0;

	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_3_4);
	for (msg_index = 0; msg_index < num; msg_index++) {
	if (msg[msg_index].flags & I2C_M_RD) {
	ret = dibx000_master_i2c_read(mst, &msg[msg_index]);
	if (ret != 0)
	return 0;
	} else {
	ret = dibx000_master_i2c_write(mst, &msg[msg_index], 1);
	if (ret != 0)
	return 0;
	}
	}

	return num;
	}

	static struct i2c_algorithm dibx000_i2c_master_gpio12_xfer_algo = {
	.master_xfer = dibx000_i2c_master_xfer_gpio12,
	.functionality = dibx000_i2c_func,
	};

	static struct i2c_algorithm dibx000_i2c_master_gpio34_xfer_algo = {
	.master_xfer = dibx000_i2c_master_xfer_gpio34,
	.functionality = dibx000_i2c_func,
	};

	static int dibx000_i2c_gate_ctrl(struct dibx000_i2c_master *mst, u8 tx[4],
	u8 addr, int onoff)
	{
	u16 val;


	if (onoff)
	val = addr << 8; // bit 7 = use master or not, if 0, the gate is open
	else
	val = 1 << 7;

	if (mst->device_rev > DIB7000)
	val <<= 1;

	tx[0] = (((mst->base_reg + 1) >> 8) & 0xff);
	tx[1] = ((mst->base_reg + 1) & 0xff);
	tx[2] = val >> 8;
	tx[3] = val & 0xff;

	return 0;
	}

	static int dibx000_i2c_gated_gpio67_xfer(struct i2c_adapter *i2c_adap,
	struct i2c_msg msg[], int num)
	{
	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
	int ret;

	if (num > 32) {
	dprintk("%s: too much I2C message to be transmitted (%i).\
	Maximum is 32", __func__, num);
	return -ENOMEM;
	}

	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_GPIO_6_7);

	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
	dprintk("could not acquire lock");
	return -EINVAL;
	}

	memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));

	/* open the gate */
	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
	mst->msg[0].addr = mst->i2c_addr;
	mst->msg[0].buf = &mst->i2c_write_buffer[0];
	mst->msg[0].len = 4;

	memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);

	/* close the gate */
	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
	mst->msg[num + 1].addr = mst->i2c_addr;
	mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
	mst->msg[num + 1].len = 4;

	ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
	num : -EIO);

	mutex_unlock(&mst->i2c_buffer_lock);
	return ret;
	}

	static struct i2c_algorithm dibx000_i2c_gated_gpio67_algo = {
	.master_xfer = dibx000_i2c_gated_gpio67_xfer,
	.functionality = dibx000_i2c_func,
	};

	static int dibx000_i2c_gated_tuner_xfer(struct i2c_adapter *i2c_adap,
	struct i2c_msg msg[], int num)
	{
	struct dibx000_i2c_master *mst = i2c_get_adapdata(i2c_adap);
	int ret;

	if (num > 32) {
	dprintk("%s: too much I2C message to be transmitted (%i).\
	Maximum is 32", __func__, num);
	return -ENOMEM;
	}

	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);

	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
	dprintk("could not acquire lock");
	return -EINVAL;
	}
	memset(mst->msg, 0, sizeof(struct i2c_msg) * (2 + num));

	/* open the gate */
	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[0], msg[0].addr, 1);
	mst->msg[0].addr = mst->i2c_addr;
	mst->msg[0].buf = &mst->i2c_write_buffer[0];
	mst->msg[0].len = 4;

	memcpy(&mst->msg[1], msg, sizeof(struct i2c_msg) * num);

	/* close the gate */
	dibx000_i2c_gate_ctrl(mst, &mst->i2c_write_buffer[4], 0, 0);
	mst->msg[num + 1].addr = mst->i2c_addr;
	mst->msg[num + 1].buf = &mst->i2c_write_buffer[4];
	mst->msg[num + 1].len = 4;

	ret = (i2c_transfer(mst->i2c_adap, mst->msg, 2 + num) == 2 + num ?
	num : -EIO);
	mutex_unlock(&mst->i2c_buffer_lock);
	return ret;
	}

	static struct i2c_algorithm dibx000_i2c_gated_tuner_algo = {
	.master_xfer = dibx000_i2c_gated_tuner_xfer,
	.functionality = dibx000_i2c_func,
	};

	struct i2c_adapter dibx000_get_i2c_adapter(struct dibx000_i2c_master mst,
	enum dibx000_i2c_interface intf,
	int gating)
	{
	struct i2c_adapter *i2c = NULL;

	switch (intf) {
	case DIBX000_I2C_INTERFACE_TUNER:
	if (gating)
	i2c = &mst->gated_tuner_i2c_adap;
	break;
	case DIBX000_I2C_INTERFACE_GPIO_1_2:
	if (!gating)
	i2c = &mst->master_i2c_adap_gpio12;
	break;
	case DIBX000_I2C_INTERFACE_GPIO_3_4:
	if (!gating)
	i2c = &mst->master_i2c_adap_gpio34;
	break;
	case DIBX000_I2C_INTERFACE_GPIO_6_7:
	if (gating)
	i2c = &mst->master_i2c_adap_gpio67;
	break;
	default:
	printk(KERN_ERR "DiBX000: incorrect I2C interface selected\n");
	break;
	}

	return i2c;
	}

	EXPORT_SYMBOL(dibx000_get_i2c_adapter);

	void dibx000_reset_i2c_master(struct dibx000_i2c_master *mst)
	{
	/* initialize the i2c-master by closing the gate */
	u8 tx[4];
	struct i2c_msg m = {.addr = mst->i2c_addr,.buf = tx,.len = 4 };

	dibx000_i2c_gate_ctrl(mst, tx, 0, 0);
	i2c_transfer(mst->i2c_adap, &m, 1);
	mst->selected_interface = 0xff; // the first time force a select of the I2C
	dibx000_i2c_select_interface(mst, DIBX000_I2C_INTERFACE_TUNER);
	}

	EXPORT_SYMBOL(dibx000_reset_i2c_master);

	static int i2c_adapter_init(struct i2c_adapter *i2c_adap,
	struct i2c_algorithm algo, const char name,
	struct dibx000_i2c_master *mst)
	{
	strncpy(i2c_adap->name, name, sizeof(i2c_adap->name));
	i2c_adap->algo = algo;
	i2c_adap->algo_data = NULL;
	i2c_set_adapdata(i2c_adap, mst);
	if (i2c_add_adapter(i2c_adap) < 0)
	return -ENODEV;
	return 0;
	}

	int dibx000_init_i2c_master(struct dibx000_i2c_master *mst, u16 device_rev,
	struct i2c_adapter *i2c_adap, u8 i2c_addr)
	{
	int ret;

	mutex_init(&mst->i2c_buffer_lock);
	if (mutex_lock_interruptible(&mst->i2c_buffer_lock) < 0) {
	dprintk("could not acquire lock");
	return -EINVAL;
	}
	memset(mst->msg, 0, sizeof(struct i2c_msg));
	mst->msg[0].addr = i2c_addr >> 1;
	mst->msg[0].flags = 0;
	mst->msg[0].buf = mst->i2c_write_buffer;
	mst->msg[0].len = 4;

	mst->device_rev = device_rev;
	mst->i2c_adap = i2c_adap;
	mst->i2c_addr = i2c_addr >> 1;

	if (device_rev == DIB7000P \|\| device_rev == DIB8000)
	mst->base_reg = 1024;
	else
	mst->base_reg = 768;

	mst->gated_tuner_i2c_adap.dev.parent = mst->i2c_adap->dev.parent;
	if (i2c_adapter_init
	(&mst->gated_tuner_i2c_adap, &dibx000_i2c_gated_tuner_algo,
	"DiBX000 tuner I2C bus", mst) != 0)
	printk(KERN_ERR
	"DiBX000: could not initialize the tuner i2c_adapter\n");

	mst->master_i2c_adap_gpio12.dev.parent = mst->i2c_adap->dev.parent;
	if (i2c_adapter_init
	(&mst->master_i2c_adap_gpio12, &dibx000_i2c_master_gpio12_xfer_algo,
	"DiBX000 master GPIO12 I2C bus", mst) != 0)
	printk(KERN_ERR
	"DiBX000: could not initialize the master i2c_adapter\n");

	mst->master_i2c_adap_gpio34.dev.parent = mst->i2c_adap->dev.parent;
	if (i2c_adapter_init
	(&mst->master_i2c_adap_gpio34, &dibx000_i2c_master_gpio34_xfer_algo,
	"DiBX000 master GPIO34 I2C bus", mst) != 0)
	printk(KERN_ERR
	"DiBX000: could not initialize the master i2c_adapter\n");

	mst->master_i2c_adap_gpio67.dev.parent = mst->i2c_adap->dev.parent;
	if (i2c_adapter_init
	(&mst->master_i2c_adap_gpio67, &dibx000_i2c_gated_gpio67_algo,
	"DiBX000 master GPIO67 I2C bus", mst) != 0)
	printk(KERN_ERR
	"DiBX000: could not initialize the master i2c_adapter\n");

	/* initialize the i2c-master by closing the gate */
	dibx000_i2c_gate_ctrl(mst, mst->i2c_write_buffer, 0, 0);

	ret = (i2c_transfer(i2c_adap, mst->msg, 1) == 1);
	mutex_unlock(&mst->i2c_buffer_lock);

	return ret;
	}

	EXPORT_SYMBOL(dibx000_init_i2c_master);

	void dibx000_exit_i2c_master(struct dibx000_i2c_master *mst)
	{
	i2c_del_adapter(&mst->gated_tuner_i2c_adap);
	i2c_del_adapter(&mst->master_i2c_adap_gpio12);
	i2c_del_adapter(&mst->master_i2c_adap_gpio34);
	i2c_del_adapter(&mst->master_i2c_adap_gpio67);
	}
	EXPORT_SYMBOL(dibx000_exit_i2c_master);


	u32 systime(void)
	{
	struct timespec t;

	t = current_kernel_time();
	return (t.tv_sec * 10000) + (t.tv_nsec / 100000);
	}
	EXPORT_SYMBOL(systime);

	MODULE_AUTHOR("Patrick Boettcher <patrick.boettcher@posteo.de>");
	MODULE_DESCRIPTION("Common function the DiBcom demodulator family");
	MODULE_LICENSE("GPL");