Commit 3f0e1e4b authored by Tang Yuantian's avatar Tang Yuantian Committed by Wolfram Sang
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i2c: mpc: Add support for SMBUS_READ_BLOCK_DATA 



Add support for SMBUS_READ_BLOCK_DATA to the i2c-mpc bus driver.

Signed-off-by: default avatarTang Yuantian <Yuantian.Tang@freescale.com>
Cc: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: default avatarWolfram Sang <w.sang@pengutronix.de>
parent 237ab406

drivers/i2c/busses/i2c-mpc.c

+49 −14
Original line number Diff line number Diff line
@@ -454,7 +454,7 @@ static int mpc_write(struct mpc_i2c *i2c, int target, 
}



static int mpc_read(struct mpc_i2c *i2c, int target,

		    u8 *data, int length, int restart)

		    u8 *data, int length, int restart, bool recv_len)

{

	unsigned timeout = i2c->adap.timeout;

	int i, result;
@@ -470,7 +470,7 @@ static int mpc_read(struct mpc_i2c *i2c, int target, 
		return result;



	if (length) {

		if (length == 1)

		if (length == 1 && !recv_len)

			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);

		else

			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA);
@@ -479,17 +479,46 @@ static int mpc_read(struct mpc_i2c *i2c, int target, 
	}



	for (i = 0; i < length; i++) {

		u8 byte;



		result = i2c_wait(i2c, timeout, 0);

		if (result < 0)

			return result;



		/*

		 * For block reads, we have to know the total length (1st byte)

		 * before we can determine if we are done.

		 */

		if (i || !recv_len) {

			/* Generate txack on next to last byte */

			if (i == length - 2)

			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);

				writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA

					 | CCR_TXAK);

			/* Do not generate stop on last byte */

			if (i == length - 1)

			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX);

		data[i] = readb(i2c->base + MPC_I2C_DR);

				writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA

					 | CCR_MTX);

		}



		byte = readb(i2c->base + MPC_I2C_DR);



		/*

		 * Adjust length if first received byte is length.

		 * The length is 1 length byte plus actually data length

		 */

		if (i == 0 && recv_len) {

			if (byte == 0 || byte > I2C_SMBUS_BLOCK_MAX)

				return -EPROTO;

			length += byte;

			/*

			 * For block reads, generate txack here if data length

			 * is 1 byte (total length is 2 bytes).

			 */

			if (length == 2)

				writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA

					 | CCR_TXAK);

		}

		data[i] = byte;

	}



	return length;
@@ -532,20 +561,26 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) 
			"Doing %s %d bytes to 0x%02x - %d of %d messages\n",

			pmsg->flags & I2C_M_RD ? "read" : "write",

			pmsg->len, pmsg->addr, i + 1, num);

		if (pmsg->flags & I2C_M_RD)

			ret =

			    mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);

		else

		if (pmsg->flags & I2C_M_RD) {

			bool recv_len = pmsg->flags & I2C_M_RECV_LEN;



			ret = mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i,

				       recv_len);

			if (recv_len && ret > 0)

				pmsg->len = ret;

		} else {

			ret =

			    mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);

		}

	}

	mpc_i2c_stop(i2c);

	return (ret < 0) ? ret : num;

}



static u32 mpc_functionality(struct i2c_adapter *adap)

{

	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;

	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL

	  | I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_FUNC_SMBUS_BLOCK_PROC_CALL;

}



static const struct i2c_algorithm mpc_algo = {