diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-s3c2410.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-s3c2410.c | 40 |
1 files changed, 21 insertions, 19 deletions
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c index 4c6036920388..fe245dfdaf4d 100644 --- a/drivers/i2c/busses/i2c-s3c2410.c +++ b/drivers/i2c/busses/i2c-s3c2410.c @@ -233,8 +233,17 @@ static bool is_ack(struct s3c24xx_i2c *i2c) int tries; for (tries = 50; tries; --tries) { - if (readl(i2c->regs + S3C2410_IICCON) - & S3C2410_IICCON_IRQPEND) { + unsigned long tmp = readl(i2c->regs + S3C2410_IICCON); + + if (!(tmp & S3C2410_IICCON_ACKEN)) { + /* + * Wait a bit for the bus to stabilize, + * delay estimated experimentally. + */ + usleep_range(100, 200); + return true; + } + if (tmp & S3C2410_IICCON_IRQPEND) { if (!(readl(i2c->regs + S3C2410_IICSTAT) & S3C2410_IICSTAT_LASTBIT)) return true; @@ -287,16 +296,6 @@ static void s3c24xx_i2c_message_start(struct s3c24xx_i2c *i2c, stat |= S3C2410_IICSTAT_START; writel(stat, i2c->regs + S3C2410_IICSTAT); - - if (i2c->quirks & QUIRK_POLL) { - while ((i2c->msg_num != 0) && is_ack(i2c)) { - i2c_s3c_irq_nextbyte(i2c, stat); - stat = readl(i2c->regs + S3C2410_IICSTAT); - - if (stat & S3C2410_IICSTAT_ARBITR) - dev_err(i2c->dev, "deal with arbitration loss\n"); - } - } } static inline void s3c24xx_i2c_stop(struct s3c24xx_i2c *i2c, int ret) @@ -703,7 +702,7 @@ static void s3c24xx_i2c_wait_idle(struct s3c24xx_i2c *i2c) static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, struct i2c_msg *msgs, int num) { - unsigned long timeout; + unsigned long timeout = 0; int ret; if (i2c->suspended) @@ -726,16 +725,19 @@ static int s3c24xx_i2c_doxfer(struct s3c24xx_i2c *i2c, s3c24xx_i2c_message_start(i2c, msgs); if (i2c->quirks & QUIRK_POLL) { - ret = i2c->msg_idx; + while ((i2c->msg_num != 0) && is_ack(i2c)) { + unsigned long stat = readl(i2c->regs + S3C2410_IICSTAT); - if (ret != num) - dev_dbg(i2c->dev, "incomplete xfer (%d)\n", ret); + i2c_s3c_irq_nextbyte(i2c, stat); - goto out; + stat = readl(i2c->regs + S3C2410_IICSTAT); + if (stat & S3C2410_IICSTAT_ARBITR) + dev_err(i2c->dev, "deal with arbitration loss\n"); + } + } else { + timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); } - timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5); - ret = i2c->msg_idx; /* |