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.
Signed-off-by: Tetsuyuki Kobayashi koba@kmckk.co.jp --- Changes for v2: - new
drivers/i2c/sh_i2c.c | 44 ++++++++++++++++++++++++++++---------------- 1 file changed, 28 insertions(+), 16 deletions(-)
diff --git a/drivers/i2c/sh_i2c.c b/drivers/i2c/sh_i2c.c index 25dbc43..e3ee804 100644 --- a/drivers/i2c/sh_i2c.c +++ b/drivers/i2c/sh_i2c.c @@ -151,29 +151,35 @@ 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); + if (i2c_set_addr(base, id, reg, 0) != 0) + return -1; udelay(10);
writeb(val, &base->icdr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + return -1;
writeb((SH_I2C_ICCR_ICE | SH_I2C_ICCR_RTS), &base->iccr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + return -1; irq_busy(base);
i2c_finish(base); + return 0; }
-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;
#if defined(CONFIG_SH73A0) - i2c_set_addr(base, id, reg, 0); + if (i2c_set_addr(base, id, reg, 0) != 0) + return -1; #else - i2c_set_addr(base, id, reg, 1); + if (i2c_set_addr(base, id, reg, 1) != 0) + return -1; udelay(100); #endif
@@ -181,12 +187,14 @@ 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) + return -1;
writeb((SH_I2C_ICCR_ICE|SH_I2C_ICCR_SCP), &base->iccr); - irq_dte(base); + if (irq_dte_with_tack(base) != 0) + return -1;
- 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 */ @@ -303,10 +311,14 @@ 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; }
@@ -327,8 +339,8 @@ 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; }