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| author | Andi Shyti <andi.shyti@kernel.org> | 2026-07-14 16:41:14 +0200 |
|---|---|---|
| committer | Andi Shyti <andi.shyti@kernel.org> | 2026-07-14 16:41:14 +0200 |
| commit | e331df87241c01b517be49b6c04f034131d6d402 (patch) | |
| tree | 8013f2e3f3087a2f9da0c8017cb33828d8d295b2 | |
| parent | 897dbc887ac08b84cdc19d6b6b4ee3d0bc6d058c (diff) | |
| parent | 07fd9385f0d87dff4b34f355f68adf701080cb24 (diff) | |
| download | linux-next-e331df87241c01b517be49b6c04f034131d6d402.tar.gz linux-next-e331df87241c01b517be49b6c04f034131d6d402.zip | |
Merge branch 'i2c/i2c-fixes' into i2c/i2c-next
| -rw-r--r-- | drivers/i2c/busses/i2c-imx.c | 36 |
1 files changed, 33 insertions, 3 deletions
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index 28313d0fad37..d5e6e2eca3b3 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -1061,11 +1061,28 @@ static inline enum imx_i2c_state i2c_imx_isr_read_continue(struct imx_i2c_struct static inline void i2c_imx_isr_read_block_data_len(struct imx_i2c_struct *i2c_imx) { u8 len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); + unsigned int temp; if (len == 0 || len > I2C_SMBUS_BLOCK_MAX) { + /* + * SMBus 3.1 6.5.7: support count byte of 0. + * I2C_SMBUS_BLOCK_MAX case should not hold the SDA either. + * So NACK it (TXAK) to not hold the bus. + */ + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_TXAK; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + + if (len == 0) { + i2c_imx->msg->buf[i2c_imx->msg_buf_idx++] = 0; + i2c_imx->msg->len = 2; + return; + } + i2c_imx->isr_result = -EPROTO; i2c_imx->state = IMX_I2C_STATE_FAILED; wake_up(&i2c_imx->queue); + return; } i2c_imx->msg->len += len; i2c_imx->msg->buf[i2c_imx->msg_buf_idx++] = len; @@ -1415,6 +1432,7 @@ static int i2c_imx_atomic_read(struct imx_i2c_struct *i2c_imx, int i, result; unsigned int temp; int block_data = msgs->flags & I2C_M_RECV_LEN; + int block_err = 0; result = i2c_imx_prepare_read(i2c_imx, msgs, false); if (result) @@ -1436,8 +1454,20 @@ static int i2c_imx_atomic_read(struct imx_i2c_struct *i2c_imx, */ if ((!i) && block_data) { len = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); - if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) - return -EPROTO; + if ((len == 0) || (len > I2C_SMBUS_BLOCK_MAX)) { + /* + * SMBus 3.1 6.5.7: support count byte of 0. + * I2C_SMBUS_BLOCK_MAX case should not hold the SDA either. + */ + if (len > I2C_SMBUS_BLOCK_MAX) + block_err = -EPROTO; + temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + temp |= I2CR_TXAK; + imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR); + msgs->buf[0] = 0; + msgs->len = 2; + continue; + } dev_dbg(&i2c_imx->adapter.dev, "<%s> read length: 0x%X\n", __func__, len); @@ -1485,7 +1515,7 @@ static int i2c_imx_atomic_read(struct imx_i2c_struct *i2c_imx, "<%s> read byte: B%d=0x%X\n", __func__, i, msgs->buf[i]); } - return 0; + return block_err; } static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs, |