[MIPS] Yosemite: Fix warnings in i2c-yoesmite by deleting the unused code.

arch/mips/pmc-sierra/yosemite/i2c-yosemite.c: In function 'titan_i2c_xfer':
arch/mips/pmc-sierra/yosemite/i2c-yosemite.c:98: warning: 'data' may be used uninitialized in this function
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/pmc-sierra/yosemite/Makefile

@@ -2,7 +2,9 @@
 # Makefile for the PMC-Sierra Titan
 #
 
-obj-y    += irq.o i2c-yosemite.o prom.o py-console.o setup.o
+obj-y    += irq.o prom.o py-console.o setup.o
 
 obj-$(CONFIG_KGDB)		+= dbg_io.o
 obj-$(CONFIG_SMP)		+= smp.o
+
+EXTRA_CFLAGS += -Werror

arch/mips/pmc-sierra/yosemite/i2c-yosemite.c

-/*
- *  Copyright (C) 2003 PMC-Sierra Inc.
- *  Author: Manish Lachwani (lachwani@pmc-sierra.com)
- *
- *  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  SOFTWARE  IS PROVIDED   ``AS  IS'' AND   ANY  EXPRESS OR IMPLIED
- *  WARRANTIES,   INCLUDING, BUT NOT  LIMITED  TO, THE IMPLIED WARRANTIES OF
- *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN
- *  NO  EVENT  SHALL   THE AUTHOR  BE    LIABLE FOR ANY   DIRECT, INDIRECT,
- *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- *  NOT LIMITED   TO, PROCUREMENT OF  SUBSTITUTE GOODS  OR SERVICES; LOSS OF
- *  USE, DATA,  OR PROFITS; OR  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
- *  ANY THEORY OF LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT
- *  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- *  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- *  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.,
- *  675 Mass Ave, Cambridge, MA 02139, USA.
- */
-
-/*
- * Detailed Description:
- *
- * This block implements the I2C interface to the slave devices like the
- * Atmel 24C32 EEPROM and the MAX 1619 Sensors device. The I2C Master interface
- * can be controlled by the SCMB block. And the SCMB block kicks in only when
- * using the Ethernet Mode of operation and __not__ the SysAD mode
- *
- * The SCMB controls the two modes: MDIO and the I2C. The MDIO mode is used to
- * communicate with the Quad-PHY from Marvel. The I2C is used to communicate
- * with the I2C slave devices.  It seems that the driver does not explicitly
- * deal with the control of SDA and SCL serial lines. So, the driver will set
- * the slave address, drive the command and then the data.  The SCMB will then
- * control the two serial lines as required.
- *
- * It seems the documents are very unclear abt this. Hence, I took some time
- * out to write the desciption to have an idea of how the I2C can actually
- * work. Currently, this Linux driver wont be integrated into the generic Linux
- * I2C framework. And finally, the I2C interface is also known as the 2BI
- * interface. 2BI means 2-bit interface referring to SDA and SCL serial lines
- * respectively.
- *
- * - Manish Lachwani (12/09/2003)
- */
-
-#include "i2c-yosemite.h"
-
-/*
- * Poll the I2C interface for the BUSY bit.
- */
-static int titan_i2c_poll(void)
-{
-	int i = 0;
-	unsigned long val = 0;
-
-	for (i = 0; i < TITAN_I2C_MAX_POLL; i++) {
-		val = TITAN_I2C_READ(TITAN_I2C_COMMAND);
-
-		if (!(val & 0x8000))
-			return 0;
-	}
-
-	return TITAN_I2C_ERR_TIMEOUT;
-}
-
-/*
- * Execute the I2C command
- */
-int titan_i2c_xfer(unsigned int slave_addr, titan_i2c_command * cmd,
-		   int size, unsigned int *addr)
-{
-	int loop, bytes = 0, i;
-	unsigned int *write_data, data, *read_data;
-	unsigned long reg_val, val;
-
-	write_data = cmd->data;
-	read_data = addr;
-
-	TITAN_I2C_WRITE(TITAN_I2C_SLAVE_ADDRESS, slave_addr);
-
-	if (cmd->type == TITAN_I2C_CMD_WRITE)
-		loop = cmd->write_size;
-	else
-		loop = size;
-
-	while (loop > 0) {
-		if ((cmd->type == TITAN_I2C_CMD_WRITE) ||
-		    (cmd->type == TITAN_I2C_CMD_READ_WRITE)) {
-
-			reg_val = TITAN_I2C_DATA;
-			for (i = 0; i < TITAN_I2C_MAX_WORDS_PER_RW;
-			     ++i, write_data += 2, reg_val += 4) {
-				if (bytes < cmd->write_size) {
-					data = write_data[0];
-					++data;
-				}
-
-				if (bytes < cmd->write_size) {
-					data = write_data[1];
-					++data;
-				}
-
-				TITAN_I2C_WRITE(reg_val, data);
-			}
-		}
-
-		TITAN_I2C_WRITE(TITAN_I2C_COMMAND,
-				(unsigned int) (cmd->type << 13));
-		if (titan_i2c_poll() != TITAN_I2C_ERR_OK)
-			return TITAN_I2C_ERR_TIMEOUT;
-
-		if ((cmd->type == TITAN_I2C_CMD_READ) ||
-		    (cmd->type == TITAN_I2C_CMD_READ_WRITE)) {
-
-			reg_val = TITAN_I2C_DATA;
-			for (i = 0; i < TITAN_I2C_MAX_WORDS_PER_RW;
-			     ++i, read_data += 2, reg_val += 4) {
-				data = TITAN_I2C_READ(reg_val);
-
-				if (bytes < size) {
-					read_data[0] = data & 0xff;
-					++bytes;
-				}
-
-				if (bytes < size) {
-					read_data[1] =
-					    ((data >> 8) & 0xff);
-					++bytes;
-				}
-			}
-		}
-
-		loop -= (TITAN_I2C_MAX_WORDS_PER_RW * 2);
-	}
-
-	/*
-	 * Read the Interrupt status and then return the appropriate error code
-	 */
-
-	val = TITAN_I2C_READ(TITAN_I2C_INTERRUPTS);
-	if (val & 0x0020)
-		return TITAN_I2C_ERR_ARB_LOST;
-
-	if (val & 0x0040)
-		return TITAN_I2C_ERR_NO_RESP;
-
-	if (val & 0x0080)
-		return TITAN_I2C_ERR_DATA_COLLISION;
-
-	return TITAN_I2C_ERR_OK;
-}
-
-/*
- * Init the I2C subsystem of the PMC-Sierra Yosemite board
- */
-int titan_i2c_init(titan_i2c_config * config)
-{
-	unsigned int val;
-
-	/*
-	 * Reset the SCMB and program into the I2C mode
-	 */
-	TITAN_I2C_WRITE(TITAN_I2C_SCMB_CONTROL, 0xA000);
-	TITAN_I2C_WRITE(TITAN_I2C_SCMB_CONTROL, 0x2000);
-
-	/*
-	 * Configure the filtera and clka values
-	 */
-	val = TITAN_I2C_READ(TITAN_I2C_SCMB_CLOCK_A);
-	val |= ((val & ~(0xF000)) | ((config->filtera << 12) & 0xF000));
-	val |= ((val & ~(0x03FF)) | (config->clka & 0x03FF));
-	TITAN_I2C_WRITE(TITAN_I2C_SCMB_CLOCK_A, val);
-
-	/*
-	 * Configure the filterb and clkb values
-	 */
-	val = TITAN_I2C_READ(TITAN_I2C_SCMB_CLOCK_B);
-	val |= ((val & ~(0xF000)) | ((config->filterb << 12) & 0xF000));
-	val |= ((val & ~(0x03FF)) | (config->clkb & 0x03FF));
-	TITAN_I2C_WRITE(TITAN_I2C_SCMB_CLOCK_B, val);
-
-	return TITAN_I2C_ERR_OK;
-}