* [PATCH v3] i2c: designware: Implement support for SMBus block read and write
@ 2016-10-31 6:51 tnhuynh
2016-10-31 12:05 ` Mika Westerberg
2016-11-07 14:11 ` Andy Shevchenko
0 siblings, 2 replies; 4+ messages in thread
From: tnhuynh @ 2016-10-31 6:51 UTC (permalink / raw)
To: Jarkko Nikula, Andy Shevchenko, Mika Westerberg, Wolfram Sang,
linux-i2c, linux-kernel
Cc: Loc Ho, Thang Nguyen, Phong Vo, patches, Tin Huynh
From: Tin Huynh <tnhuynh@apm.com>
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>
---
Change from V2:
- Change subject of email
- Add a helper function to handle
length byte receiving
Change from V1:
- Remove empty lines
- Add flags variable to make clean code
- Change DW_DEFAULT_FUNCTIONALITY
in i2c-designware-pcidrv.c
---
drivers/i2c/busses/i2c-designware-core.c | 45 +++++++++++++++++++++++++--
drivers/i2c/busses/i2c-designware-pcidrv.c | 1 +
drivers/i2c/busses/i2c-designware-platdrv.c | 1 +
3 files changed, 44 insertions(+), 3 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index 1fe93c4..69c7ab8 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -543,6 +543,7 @@ static void i2c_dw_xfer_init(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
@@ -588,8 +589,15 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
* detected from the registers so we set it always
* when writing/reading the last byte.
*/
+
+ /*
+ * i2c-core.c always set 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) {
@@ -614,7 +622,12 @@ static void i2c_dw_xfer_init(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;
@@ -635,6 +648,25 @@ static void i2c_dw_xfer_init(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) ? len + 2 : len + 1;
+ dev->tx_buf_len = len > dev->rx_outstanding ?
+ len - dev->rx_outstanding : 0;
+ 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)
{
@@ -659,7 +691,14 @@ static void i2c_dw_xfer_init(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--;
}
diff --git a/drivers/i2c/busses/i2c-designware-pcidrv.c b/drivers/i2c/busses/i2c-designware-pcidrv.c
index 96f8230..8ffe2da 100644
--- a/drivers/i2c/busses/i2c-designware-pcidrv.c
+++ b/drivers/i2c/busses/i2c-designware-pcidrv.c
@@ -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 */
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 0b42a12..886fb62 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -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 |
--
1.7.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH v3] i2c: designware: Implement support for SMBus block read and write
2016-10-31 6:51 [PATCH v3] i2c: designware: Implement support for SMBus block read and write tnhuynh
@ 2016-10-31 12:05 ` Mika Westerberg
2016-10-31 13:16 ` Jarkko Nikula
2016-11-07 14:11 ` Andy Shevchenko
1 sibling, 1 reply; 4+ messages in thread
From: Mika Westerberg @ 2016-10-31 12:05 UTC (permalink / raw)
To: tnhuynh
Cc: Jarkko Nikula, Andy Shevchenko, Wolfram Sang, linux-i2c,
linux-kernel, Loc Ho, Thang Nguyen, Phong Vo, patches
On Mon, Oct 31, 2016 at 01:51:17PM +0700, tnhuynh@apm.com wrote:
> From: Tin Huynh <tnhuynh@apm.com>
>
> 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>
Looks good to me,
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v3] i2c: designware: Implement support for SMBus block read and write
2016-10-31 12:05 ` Mika Westerberg
@ 2016-10-31 13:16 ` Jarkko Nikula
0 siblings, 0 replies; 4+ messages in thread
From: Jarkko Nikula @ 2016-10-31 13:16 UTC (permalink / raw)
To: Mika Westerberg, tnhuynh
Cc: Andy Shevchenko, Wolfram Sang, linux-i2c, linux-kernel, Loc Ho,
Thang Nguyen, Phong Vo, patches
On 10/31/2016 02:05 PM, Mika Westerberg wrote:
> On Mon, Oct 31, 2016 at 01:51:17PM +0700, tnhuynh@apm.com wrote:
>> From: Tin Huynh <tnhuynh@apm.com>
>>
>> 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>
>
> Looks good to me,
>
> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH v3] i2c: designware: Implement support for SMBus block read and write
2016-10-31 6:51 [PATCH v3] i2c: designware: Implement support for SMBus block read and write tnhuynh
2016-10-31 12:05 ` Mika Westerberg
@ 2016-11-07 14:11 ` Andy Shevchenko
1 sibling, 0 replies; 4+ messages in thread
From: Andy Shevchenko @ 2016-11-07 14:11 UTC (permalink / raw)
To: tnhuynh, Jarkko Nikula, Mika Westerberg, Wolfram Sang, linux-i2c,
linux-kernel
Cc: Loc Ho, Thang Nguyen, Phong Vo, patches
On Mon, 2016-10-31 at 13:51 +0700, tnhuynh@apm.com wrote:
> From: Tin Huynh <tnhuynh@apm.com>
>
> 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.
My comments below.
> @@ -543,6 +543,7 @@ static void i2c_dw_xfer_init(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;
+ empty line.
> /*
> * if target address has changed, we need to
> * reprogram the target address in the i2c
> @@ -588,8 +589,15 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev
> *dev)
> * detected from the registers so we set it
> always
> * when writing/reading the last byte.
> */
> +
> + /*
> + * i2c-core.c always set the buffer length of
set -> sets
> + * 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.
> + */
>
> @@ -635,6 +648,25 @@ static void i2c_dw_xfer_init(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
Add dot to the end, please.
> + */
> + len = (flags & I2C_CLIENT_PEC) ? len + 2 : len + 1;
len += flags & I2C_CLIENT_PEC ? 2 : 1;
> + dev->tx_buf_len = len > dev->rx_outstanding ?
> + len - dev->rx_outstanding : 0;
Can be len more than twice longer as rx_outstanding?
Would it be better to write as
tx_buf_len = len - min(len, 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)
> {
> @@ -659,7 +691,14 @@ static void i2c_dw_xfer_init(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;
+ empty line.
> + *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) {
Is it my mail client or indentation is wrong?
> + len = i2c_dw_recv_len(dev, *buf);
> + }
> + buf++;
> dev->rx_outstanding--;
> }
--
Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Intel Finland Oy
^ permalink raw reply [flat|nested] 4+ messages in thread
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2016-10-31 6:51 [PATCH v3] i2c: designware: Implement support for SMBus block read and write tnhuynh
2016-10-31 12:05 ` Mika Westerberg
2016-10-31 13:16 ` Jarkko Nikula
2016-11-07 14:11 ` Andy Shevchenko
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