diff options
Diffstat (limited to 'drivers/i2c/busses/i2c-xiic.c')
| -rw-r--r-- | drivers/i2c/busses/i2c-xiic.c | 62 |
1 files changed, 38 insertions, 24 deletions
diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c index 90c1c362394d..087b2951942e 100644 --- a/drivers/i2c/busses/i2c-xiic.c +++ b/drivers/i2c/busses/i2c-xiic.c @@ -46,34 +46,36 @@ enum xiic_endian { /** * struct xiic_i2c - Internal representation of the XIIC I2C bus - * @dev: Pointer to device structure - * @base: Memory base of the HW registers - * @wait: Wait queue for callers - * @adap: Kernel adapter representation - * @tx_msg: Messages from above to be sent - * @lock: Mutual exclusion - * @tx_pos: Current pos in TX message - * @nmsgs: Number of messages in tx_msg - * @state: See STATE_ - * @rx_msg: Current RX message - * @rx_pos: Position within current RX message + * @dev: Pointer to device structure + * @base: Memory base of the HW registers + * @wait: Wait queue for callers + * @adap: Kernel adapter representation + * @tx_msg: Messages from above to be sent + * @lock: Mutual exclusion + * @tx_pos: Current pos in TX message + * @nmsgs: Number of messages in tx_msg + * @rx_msg: Current RX message + * @rx_pos: Position within current RX message * @endianness: big/little-endian byte order - * @clk: Pointer to AXI4-lite input clock + * @clk: Pointer to AXI4-lite input clock + * @state: See STATE_ + * @singlemaster: Indicates bus is single master */ struct xiic_i2c { - struct device *dev; - void __iomem *base; - wait_queue_head_t wait; - struct i2c_adapter adap; - struct i2c_msg *tx_msg; - struct mutex lock; - unsigned int tx_pos; - unsigned int nmsgs; - enum xilinx_i2c_state state; - struct i2c_msg *rx_msg; - int rx_pos; - enum xiic_endian endianness; + struct device *dev; + void __iomem *base; + wait_queue_head_t wait; + struct i2c_adapter adap; + struct i2c_msg *tx_msg; + struct mutex lock; + unsigned int tx_pos; + unsigned int nmsgs; + struct i2c_msg *rx_msg; + int rx_pos; + enum xiic_endian endianness; struct clk *clk; + enum xilinx_i2c_state state; + bool singlemaster; }; @@ -526,6 +528,15 @@ static int xiic_busy(struct xiic_i2c *i2c) if (i2c->tx_msg) return -EBUSY; + /* In single master mode bus can only be busy, when in use by this + * driver. If the register indicates bus being busy for some reason we + * should ignore it, since bus will never be released and i2c will be + * stuck forever. + */ + if (i2c->singlemaster) { + return 0; + } + /* for instance if previous transfer was terminated due to TX error * it might be that the bus is on it's way to become available * give it at most 3 ms to wake @@ -811,6 +822,9 @@ static int xiic_i2c_probe(struct platform_device *pdev) goto err_clk_dis; } + i2c->singlemaster = + of_property_read_bool(pdev->dev.of_node, "single-master"); + /* * Detect endianness * Try to reset the TX FIFO. Then check the EMPTY flag. If it is not |