i2c: sh_i2c.c: check error in i2c_read and i2c_write

Before this patch, i2c_{read,write} always returned 0.
Check TACK in i2c_raw_{read,write} so that i2c_{read,write} return non-zero when error.

Acked-by: Nobuhiro Iwamatsu <nobuhiro.iwamatsu.yj@renesas.com>
Signed-off-by: Tetsuyuki Kobayashi <koba@kmckk.co.jp>
This commit is contained in:
Tetsuyuki Kobayashi 2012-09-13 19:08:01 +00:00 committed by Heiko Schocher
parent d042d7121b
commit 0e5fb33cf7

View file

@ -134,29 +134,37 @@ static void i2c_finish(struct sh_i2c *base)
writeb(readb(&base->iccr) & ~SH_I2C_ICCR_ICE, &base->iccr);
}
static void i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 val)
static int i2c_raw_write(struct sh_i2c *base, u8 id, u8 reg, u8 val)
{
i2c_set_addr(base, id, reg, 0);
int ret = -1;
if (i2c_set_addr(base, id, reg, 0) != 0)
goto exit0;
udelay(10);
writeb(val, &base->icdr);
irq_dte(base);
if (irq_dte_with_tack(base) != 0)
goto exit0;
writeb((SH_I2C_ICCR_ICE | SH_I2C_ICCR_RTS), &base->iccr);
irq_dte(base);
if (irq_dte_with_tack(base) != 0)
goto exit0;
irq_busy(base);
ret = 0;
exit0:
i2c_finish(base);
return ret;
}
static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
static int i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
{
u8 ret;
int ret = -1;
#if defined(CONFIG_SH73A0)
i2c_set_addr(base, id, reg, 0);
if (i2c_set_addr(base, id, reg, 0) != 0)
goto exit0;
#else
i2c_set_addr(base, id, reg, 1);
if (i2c_set_addr(base, id, reg, 1) != 0)
goto exit0;
udelay(100);
#endif
@ -164,17 +172,19 @@ static u8 i2c_raw_read(struct sh_i2c *base, u8 id, u8 reg)
irq_dte(base);
writeb(id << 1 | 0x01, &base->icdr);
irq_dte(base);
if (irq_dte_with_tack(base) != 0)
goto exit0;
writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_SCP), &base->iccr);
irq_dte(base);
if (irq_dte_with_tack(base) != 0)
goto exit0;
ret = readb(&base->icdr);
ret = readb(&base->icdr) & 0xff;
writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_RACK), &base->iccr);
readb(&base->icdr); /* Dummy read */
irq_busy(base);
exit0:
i2c_finish(base);
return ret;
@ -286,10 +296,14 @@ void i2c_init(int speed, int slaveaddr)
*/
int i2c_read(u8 chip, u32 addr, int alen, u8 *buffer, int len)
{
int ret;
int i = 0;
for (i = 0 ; i < len ; i++)
buffer[i] = i2c_raw_read(base, chip, addr + i);
for (i = 0 ; i < len ; i++) {
ret = i2c_raw_read(base, chip, addr + i);
if (ret < 0)
return -1;
buffer[i] = ret & 0xff;
}
return 0;
}
@ -310,8 +324,8 @@ int i2c_write(u8 chip, u32 addr, int alen, u8 *buffer, int len)
{
int i = 0;
for (i = 0; i < len ; i++)
i2c_raw_write(base, chip, addr + i, buffer[i]);
if (i2c_raw_write(base, chip, addr + i, buffer[i]) != 0)
return -1;
return 0;
}