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| author | Andrzej Hajda <a.hajda@samsung.com> | 2017-02-22 12:04:34 +0100 |
|---|---|---|
| committer | Wolfram Sang <wsa@the-dreams.de> | 2017-02-23 13:01:22 +0100 |
| commit | 7999eecb7e5675c3c7c2981a3ba9be6fc8e2ee27 (patch) | |
| tree | 0a5e7525ac2dc8de763b273c8940918cac241f93 /drivers/i2c | |
| parent | fd1c9c8568439198a66f42108a9b01854e25346e (diff) | |
| download | linux-rpi-7999eecb7e5675c3c7c2981a3ba9be6fc8e2ee27.tar.gz linux-rpi-7999eecb7e5675c3c7c2981a3ba9be6fc8e2ee27.tar.bz2 linux-rpi-7999eecb7e5675c3c7c2981a3ba9be6fc8e2ee27.zip | |
i2c: exynos5: fix arbitration lost handling
In case of arbitration lost adequate interrupt sometimes is not signaled.
As a result transfer timeouts and is not retried, as it should. To avoid
such cases code is added to check transaction status in case of every
interrupt.
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Tested-by: Andi Shyti <andi.shyti@samsung.com>
Reviewed-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Diffstat (limited to 'drivers/i2c')
| -rw-r--r-- | drivers/i2c/busses/i2c-exynos5.c | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c index 00e81e3564ff..cbd93ce0661f 100644 --- a/drivers/i2c/busses/i2c-exynos5.c +++ b/drivers/i2c/busses/i2c-exynos5.c @@ -130,12 +130,32 @@ /* I2C_TRANS_STATUS register bits */ #define HSI2C_MASTER_BUSY (1u << 17) #define HSI2C_SLAVE_BUSY (1u << 16) + +/* I2C_TRANS_STATUS register bits for Exynos5 variant */ #define HSI2C_TIMEOUT_AUTO (1u << 4) #define HSI2C_NO_DEV (1u << 3) #define HSI2C_NO_DEV_ACK (1u << 2) #define HSI2C_TRANS_ABORT (1u << 1) #define HSI2C_TRANS_DONE (1u << 0) +/* I2C_TRANS_STATUS register bits for Exynos7 variant */ +#define HSI2C_MASTER_ST_MASK 0xf +#define HSI2C_MASTER_ST_IDLE 0x0 +#define HSI2C_MASTER_ST_START 0x1 +#define HSI2C_MASTER_ST_RESTART 0x2 +#define HSI2C_MASTER_ST_STOP 0x3 +#define HSI2C_MASTER_ST_MASTER_ID 0x4 +#define HSI2C_MASTER_ST_ADDR0 0x5 +#define HSI2C_MASTER_ST_ADDR1 0x6 +#define HSI2C_MASTER_ST_ADDR2 0x7 +#define HSI2C_MASTER_ST_ADDR_SR 0x8 +#define HSI2C_MASTER_ST_READ 0x9 +#define HSI2C_MASTER_ST_WRITE 0xa +#define HSI2C_MASTER_ST_NO_ACK 0xb +#define HSI2C_MASTER_ST_LOSE 0xc +#define HSI2C_MASTER_ST_WAIT 0xd +#define HSI2C_MASTER_ST_WAIT_CMD 0xe + /* I2C_ADDR register bits */ #define HSI2C_SLV_ADDR_SLV(x) ((x & 0x3ff) << 0) #define HSI2C_SLV_ADDR_MAS(x) ((x & 0x3ff) << 10) @@ -437,6 +457,7 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) int_status = readl(i2c->regs + HSI2C_INT_STATUS); writel(int_status, i2c->regs + HSI2C_INT_STATUS); + trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); /* handle interrupt related to the transfer status */ if (i2c->variant->hw == HSI2C_EXYNOS7) { @@ -460,8 +481,12 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id) i2c->state = -ETIMEDOUT; goto stop; } + + if ((trans_status & HSI2C_MASTER_ST_MASK) == HSI2C_MASTER_ST_LOSE) { + i2c->state = -EAGAIN; + goto stop; + } } else if (int_status & HSI2C_INT_I2C) { - trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS); if (trans_status & HSI2C_NO_DEV_ACK) { dev_dbg(i2c->dev, "No ACK from device\n"); i2c->state = -ENXIO; |