mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-12 21:57:43 +00:00
Code Issues Releases Wiki Activity

i2c: designware: Implement support for SMBus block read and write

Browse source 
Free and Open IPMI use SMBUS BLOCK Read/Write to support SSIF protocol.
However, I2C Designware Core Driver doesn't handle the case at the moment.
The below patch supports this feature.

Signed-off-by: Tin Huynh <tnhuynh@apm.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Tin Huynh 2016-11-10 09:56:33 +07:00 committed by Wolfram Sang
parent 379883cc67
commit c3ae106050
3 changed files with 45 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

46
drivers/i2c/busses/i2c-designware-core.c
View file

@ -554,6 +554,8 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
intr_mask = DW_IC_INTR_DEFAULT_MASK;
for (; dev->msg_write_idx < dev->msgs_num; dev->msg_write_idx++) {
u32 flags = msgs[dev->msg_write_idx].flags;
/*
* if target address has changed, we need to
* reprogram the target address in the i2c
@ -599,8 +601,15 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
* detected from the registers so we set it always
* when writing/reading the last byte.
*/
/*
* i2c-core.c always sets the buffer length of
* I2C_FUNC_SMBUS_BLOCK_DATA to 1. The length will
* be adjusted when receiving the first byte.
* Thus we can't stop the transaction here.
*/
if (dev->msg_write_idx == dev->msgs_num - 1 &&
buf_len == 1)
buf_len == 1 && !(flags & I2C_M_RECV_LEN))
cmd |= BIT(9);
if (need_restart) {
@ -625,7 +634,12 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
dev->tx_buf = buf;
dev->tx_buf_len = buf_len;
if (buf_len > 0) {
/*
* Because we don't know the buffer length in the
* I2C_FUNC_SMBUS_BLOCK_DATA case, we can't stop
* the transaction here.
*/
if (buf_len > 0 || flags & I2C_M_RECV_LEN) {
/* more bytes to be written */
dev->status |= STATUS_WRITE_IN_PROGRESS;
break;
@ -646,6 +660,24 @@ i2c_dw_xfer_msg(struct dw_i2c_dev *dev)
dw_writel(dev, intr_mask, DW_IC_INTR_MASK);
}
static u8
i2c_dw_recv_len(struct dw_i2c_dev *dev, u8 len)
{
struct i2c_msg *msgs = dev->msgs;
u32 flags = msgs[dev->msg_read_idx].flags;
/*
* Adjust the buffer length and mask the flag
* after receiving the first byte.
*/
len += (flags & I2C_CLIENT_PEC) ? 2 : 1;
dev->tx_buf_len = len - min_t(u8, len, dev->rx_outstanding);
msgs[dev->msg_read_idx].len = len;
msgs[dev->msg_read_idx].flags &= ~I2C_M_RECV_LEN;
return len;
}
static void
i2c_dw_read(struct dw_i2c_dev *dev)
{
@ -670,7 +702,15 @@ i2c_dw_read(struct dw_i2c_dev *dev)
rx_valid = dw_readl(dev, DW_IC_RXFLR);
for (; len > 0 && rx_valid > 0; len--, rx_valid--) {
*buf++ = dw_readl(dev, DW_IC_DATA_CMD);
u32 flags = msgs[dev->msg_read_idx].flags;
*buf = dw_readl(dev, DW_IC_DATA_CMD);
/* Ensure length byte is a valid value */
if (flags & I2C_M_RECV_LEN &&
*buf <= I2C_SMBUS_BLOCK_MAX && *buf > 0) {
len = i2c_dw_recv_len(dev, *buf);
}
buf++;
dev->rx_outstanding--;
}

1
drivers/i2c/busses/i2c-designware-pcidrv.c
View file

@ -75,6 +75,7 @@ struct dw_pci_controller {
I2C_FUNC_SMBUS_BYTE | \
I2C_FUNC_SMBUS_BYTE_DATA | \
I2C_FUNC_SMBUS_WORD_DATA | \
I2C_FUNC_SMBUS_BLOCK_DATA | \
I2C_FUNC_SMBUS_I2C_BLOCK)
/* Merrifield HCNT/LCNT/SDA hold time */

1
drivers/i2c/busses/i2c-designware-platdrv.c
View file

@ -220,6 +220,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
I2C_FUNC_SMBUS_BYTE |
I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_BLOCK_DATA |
I2C_FUNC_SMBUS_I2C_BLOCK;
dev->master_cfg = DW_IC_CON_MASTER | DW_IC_CON_SLAVE_DISABLE |