diff options
| author | Laxman Dewangan <ldewangan@nvidia.com> | 2012-03-27 18:57:11 +0530 |
|---|---|---|
| committer | Simone Willett <swillett@nvidia.com> | 2012-04-18 18:36:31 -0700 |
| commit | 28adfa50e474f5a35c720e043575d9f66252de7d (patch) | |
| tree | d7c027dece168b032234255ca22524e514236fba /drivers | |
| parent | 3069e6a7179f77469274112a94d8556445ee63e4 (diff) | |
i2c: tegra: support for I2C_M_NOSTART protocol mangling
Adding support for protocol mangling I2C_M_NOSTART.
Change-Id: I6cc0c96b3c374d452ea886a0f983dc5d31c4575c
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/92573
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/i2c/busses/i2c-tegra.c | 30 |
1 files changed, 26 insertions, 4 deletions
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c index a4c1e0d82939..25ad6dca3884 100644 --- a/drivers/i2c/busses/i2c-tegra.c +++ b/drivers/i2c/busses/i2c-tegra.c @@ -106,13 +106,26 @@ #define I2C_HEADER_10BIT_ADDR (1<<18) #define I2C_HEADER_IE_ENABLE (1<<17) #define I2C_HEADER_REPEAT_START (1<<16) +#define I2C_HEADER_CONTINUE_XFER (1<<15) #define I2C_HEADER_MASTER_ADDR_SHIFT 12 #define I2C_HEADER_SLAVE_ADDR_SHIFT 1 #define SL_ADDR1(addr) (addr & 0xff) #define SL_ADDR2(addr) ((addr >> 8) & 0xff) +/* + * msg_end_type: The bus control which need to be send at end of transfer. + * @MSG_END_STOP: Send stop pulse at end of transfer. + * @MSG_END_REPEAT_START: Send repeat start at end of transfer. + * @MSG_END_CONTINUE: The following on message is coming and so do not send + * stop or repeat start. + */ +enum msg_end_type { + MSG_END_STOP, + MSG_END_REPEAT_START, + MSG_END_CONTINUE, +}; struct tegra_i2c_dev; @@ -621,7 +634,7 @@ err: } static int tegra_i2c_xfer_msg(struct tegra_i2c_bus *i2c_bus, - struct i2c_msg *msg, int stop) + struct i2c_msg *msg, enum msg_end_type end_state) { struct tegra_i2c_dev *i2c_dev = i2c_bus->dev; u32 int_mask; @@ -654,8 +667,11 @@ static int tegra_i2c_xfer_msg(struct tegra_i2c_bus *i2c_bus, i2c_writel(i2c_dev, i2c_dev->payload_size, I2C_TX_FIFO); i2c_dev->io_header = I2C_HEADER_IE_ENABLE; - if (!stop) + if (end_state == MSG_END_CONTINUE) + i2c_dev->io_header |= I2C_HEADER_CONTINUE_XFER; + else if (end_state == MSG_END_REPEAT_START) i2c_dev->io_header |= I2C_HEADER_REPEAT_START; + if (msg->flags & I2C_M_TEN) { i2c_dev->io_header |= msg->addr; i2c_dev->io_header |= I2C_HEADER_10BIT_ADDR; @@ -772,8 +788,14 @@ static int tegra_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], tegra_i2c_clock_enable(i2c_dev); for (i = 0; i < num; i++) { - int stop = (i == (num - 1)) ? 1 : 0; - ret = tegra_i2c_xfer_msg(i2c_bus, &msgs[i], stop); + enum msg_end_type end_type = MSG_END_STOP; + if (i < (num - 1)) { + if (msgs[i + 1].flags & I2C_M_NOSTART) + end_type = MSG_END_CONTINUE; + else + end_type = MSG_END_REPEAT_START; + } + ret = tegra_i2c_xfer_msg(i2c_bus, &msgs[i], end_type); if (ret) break; } |