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 --- Changes for v2: - new Changes for v3: - call i2c_finsih before returning i2c_{read,write} even if error occured.
drivers/i2c/sh_i2c.c | 50 ++++++++++++++++++++++++++++++++------------------ 1 file changed, 32 insertions(+), 18 deletions(-)
diff --git a/drivers/i2c/sh_i2c.c b/drivers/i2c/sh_i2c.c index 1f5104c..6a5ecba 100644 --- a/drivers/i2c/sh_i2c.c +++ b/drivers/i2c/sh_i2c.c @@ -150,29 +150,37 @@ 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
@@ -180,17 +188,19 @@ 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; @@ -302,10 +312,14 @@ 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; }
@@ -326,8 +340,8 @@ 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; }