Example #1
0
/**
 * i2c_pnx_master_rcv - receive data from slave
 * @adap:		pointer to I2C adapter structure
 *
 * Reads one byte data from the slave
 */
static int i2c_pnx_master_rcv(struct i2c_adapter *adap)
{
	struct i2c_pnx_algo_data *alg_data = adap->algo_data;
	unsigned int val = 0;
	u32 ctl = 0;

	dev_dbg(&adap->dev, "%s(): entering: stat = %04x.\n",
		__func__, ioread32(I2C_REG_STS(alg_data)));

	/* Check, whether there is already data,
	 * or we didn't 'ask' for it yet.
	 */
	if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
		dev_dbg(&adap->dev, "%s(): Write dummy data to fill "
			"Rx-fifo...\n", __func__);

		if (alg_data->mif.len == 1) {
			/* Last byte, do not acknowledge next rcv. */
			val |= stop_bit;
			if (!alg_data->last)
				val |= start_bit;

			/*
			 * Enable interrupt RFDAIE (data in Rx fifo),
			 * and disable DRMIE (need data for Tx)
			 */
			ctl = ioread32(I2C_REG_CTL(alg_data));
			ctl |= mcntrl_rffie | mcntrl_daie;
			ctl &= ~mcntrl_drmie;
			iowrite32(ctl, I2C_REG_CTL(alg_data));
		}

		/*
		 * Now we'll 'ask' for data:
		 * For each byte we want to receive, we must
		 * write a (dummy) byte to the Tx-FIFO.
		 */
		iowrite32(val, I2C_REG_TX(alg_data));

		return 0;
	}

	/* Handle data. */
	if (alg_data->mif.len > 0) {
		val = ioread32(I2C_REG_RX(alg_data));
		*alg_data->mif.buf++ = (u8) (val & 0xff);
		dev_dbg(&adap->dev, "%s(): rcv 0x%x [%d]\n", __func__, val,
			alg_data->mif.len);

		alg_data->mif.len--;
		if (alg_data->mif.len == 0) {
			if (alg_data->last)
				/* Wait until the STOP is seen. */
				if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
					dev_err(&adap->dev, "The bus is still "
						"active after timeout\n");

			/* Disable master interrupts */
			ctl = ioread32(I2C_REG_CTL(alg_data));
			ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
				 mcntrl_drmie | mcntrl_daie);
			iowrite32(ctl, I2C_REG_CTL(alg_data));

			/* Kill timer. */
			del_timer_sync(&alg_data->mif.timer);
			complete(&alg_data->mif.complete);
		}
	}

	dev_dbg(&adap->dev, "%s(): exiting: stat = %04x.\n",
		__func__, ioread32(I2C_REG_STS(alg_data)));

	return 0;
}
Example #2
0
/**
 * i2c_pnx_master_rcv - receive data from slave
 * @adap:		pointer to I2C adapter structure
 *
 * Reads one byte data from the slave
 */
static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data)
{
	unsigned int val = 0;
	u32 ctl = 0;

	dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
		__func__, ioread32(I2C_REG_STS(alg_data)));

	/* Check, whether there is already data,
	 * or we didn't 'ask' for it yet.
	 */
	if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
		/* 'Asking' is done asynchronously, e.g. dummy TX of several
		 * bytes is done before the first actual RX arrives in FIFO.
		 * Therefore, ordered bytes (via TX) are counted separately.
		 */
		if (alg_data->mif.order) {
			dev_dbg(&alg_data->adapter.dev,
				"%s(): Write dummy data to fill Rx-fifo...\n",
				__func__);

			if (alg_data->mif.order == 1) {
				/* Last byte, do not acknowledge next rcv. */
				val |= stop_bit;

				/*
				 * Enable interrupt RFDAIE (data in Rx fifo),
				 * and disable DRMIE (need data for Tx)
				 */
				ctl = ioread32(I2C_REG_CTL(alg_data));
				ctl |= mcntrl_rffie | mcntrl_daie;
				ctl &= ~mcntrl_drmie;
				iowrite32(ctl, I2C_REG_CTL(alg_data));
			}

			/*
			 * Now we'll 'ask' for data:
			 * For each byte we want to receive, we must
			 * write a (dummy) byte to the Tx-FIFO.
			 */
			iowrite32(val, I2C_REG_TX(alg_data));
			alg_data->mif.order--;
		}
		return 0;
	}

	/* Handle data. */
	if (alg_data->mif.len > 0) {
		val = ioread32(I2C_REG_RX(alg_data));
		*alg_data->mif.buf++ = (u8) (val & 0xff);
		dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n",
			__func__, val, alg_data->mif.len);

		alg_data->mif.len--;
		if (alg_data->mif.len == 0) {
			if (alg_data->last)
				/* Wait until the STOP is seen. */
				if (wait_timeout(alg_data))
					dev_err(&alg_data->adapter.dev,
						"The bus is still active after timeout\n");

			/* Disable master interrupts */
			ctl = ioread32(I2C_REG_CTL(alg_data));
			ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
				 mcntrl_drmie | mcntrl_daie);
			iowrite32(ctl, I2C_REG_CTL(alg_data));

			/* Kill timer. */
			del_timer_sync(&alg_data->mif.timer);
			complete(&alg_data->mif.complete);
		}
	}

	dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
		__func__, ioread32(I2C_REG_STS(alg_data)));

	return 0;
}
static int i2c_pnx_master_rcv(struct i2c_pnx_algo_data *alg_data)
{
	unsigned int val = 0;
	u32 ctl = 0;

	dev_dbg(&alg_data->adapter.dev, "%s(): entering: stat = %04x.\n",
		__func__, ioread32(I2C_REG_STS(alg_data)));

	/*                                      
                                  
  */
	if (ioread32(I2C_REG_STS(alg_data)) & mstatus_rfe) {
		dev_dbg(&alg_data->adapter.dev,
			"%s(): Write dummy data to fill Rx-fifo...\n",
			__func__);

		if (alg_data->mif.len == 1) {
			/*                                         */
			val |= stop_bit;

			/*
                                                
                                          
    */
			ctl = ioread32(I2C_REG_CTL(alg_data));
			ctl |= mcntrl_rffie | mcntrl_daie;
			ctl &= ~mcntrl_drmie;
			iowrite32(ctl, I2C_REG_CTL(alg_data));
		}

		/*
                              
                                              
                                         
   */
		iowrite32(val, I2C_REG_TX(alg_data));

		return 0;
	}

	/*              */
	if (alg_data->mif.len > 0) {
		val = ioread32(I2C_REG_RX(alg_data));
		*alg_data->mif.buf++ = (u8) (val & 0xff);
		dev_dbg(&alg_data->adapter.dev, "%s(): rcv 0x%x [%d]\n",
			__func__, val, alg_data->mif.len);

		alg_data->mif.len--;
		if (alg_data->mif.len == 0) {
			if (alg_data->last)
				/*                              */
				if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
					dev_err(&alg_data->adapter.dev,
						"The bus is still active after timeout\n");

			/*                           */
			ctl = ioread32(I2C_REG_CTL(alg_data));
			ctl &= ~(mcntrl_afie | mcntrl_naie | mcntrl_rffie |
				 mcntrl_drmie | mcntrl_daie);
			iowrite32(ctl, I2C_REG_CTL(alg_data));

			/*             */
			del_timer_sync(&alg_data->mif.timer);
			complete(&alg_data->mif.complete);
		}
	}

	dev_dbg(&alg_data->adapter.dev, "%s(): exiting: stat = %04x.\n",
		__func__, ioread32(I2C_REG_STS(alg_data)));

	return 0;
}