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i2c: exynos5: fix arbitration lost handling

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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>
This commit is contained in:
Andrzej Hajda 2017-02-22 12:04:34 +01:00 committed by Wolfram Sang
parent fd1c9c8568
commit 7999eecb7e
1 changed files with 26 additions and 1 deletions
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27
drivers/i2c/busses/i2c-exynos5.c
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@ -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;