Re: [RFC V2 04/12] i2c: opal: make use of the new infrastructure for quirks
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: 2015-03-10 23:13:17
Also in:
linux-arm-kernel, linux-i2c, linux-mips, linuxppc-dev
On Tue, 2015-03-10 at 22:43 +0530, Neelesh Gupta wrote:
I tested the i2c opal driver after updating the patch as below.
Basically I think we can also support write-then-{read/write}
for the number of messages = 2.
Ben, any issues if we support both write plus read/write in the
opal driver ?Nope, in fact it's a good idea, I found myself having to expoes such an interface to some userspace tool of ours. However...
quoted hunk ↗ jump to hunk
diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c index 16f90b1..85412ba 100644 --- a/drivers/i2c/busses/i2c-opal.c +++ b/drivers/i2c/busses/i2c-opal.c@@ -104,18 +104,8 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); break; case 2: - /* For two messages, we basically support only simple - * smbus transactions of a write plus a read. We might - * want to allow also two writes but we'd have to bounce - * the data into a single buffer. - */ - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) - return -EOPNOTSUPP;
Don't we still want to enforce that the first message is a write ? Somebody may not be looking at the quirks...
- if (msgs[0].len > 4) - return -EOPNOTSUPP;
And that the len is supported...
- if (msgs[0].addr != msgs[1].addr) - return -EOPNOTSUPP;
Same... Ie, the quirk indicates to the callers what we support, but we should still check that we aren't called with something that doesn't match.
quoted hunk ↗ jump to hunk
- req.type = OPAL_I2C_SM_READ; + req.type = (msgs[1].flags & I2C_M_RD) ? + OPAL_I2C_SM_READ : OPAL_I2C_SM_WRITE; req.addr = cpu_to_be16(msgs[0].addr); req.subaddr_sz = msgs[0].len; for (i = 0; i < msgs[0].len; i++)@@ -210,6 +200,11 @@ static const struct i2c_algorithm i2c_opal_algo = { .functionality = i2c_opal_func, }; +static struct i2c_adapter_quirks i2c_opal_quirks = { + .flags = I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | I2C_AQ_COMB_SAME_ADDR, + .max_comb_1st_msg_len = 4, +}; + static int i2c_opal_probe(struct platform_device *pdev) { struct i2c_adapter *adapter;@@ -232,6 +227,7 @@ static int i2c_opal_probe(struct platform_device *pdev) adapter->algo = &i2c_opal_algo; adapter->algo_data = (void *)(unsigned long)opal_id; + adapter->quirks = &i2c_opal_quirks; adapter->dev.parent = &pdev->dev; adapter->dev.of_node = of_node_get(pdev->dev.of_node); pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);On 02/25/2015 09:31 PM, Wolfram Sang wrote:quoted
From: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> --- drivers/i2c/busses/i2c-opal.c | 22 +++++++++++----------- 1 file changed, 11 insertions(+), 11 deletions(-)diff --git a/drivers/i2c/busses/i2c-opal.c b/drivers/i2c/busses/i2c-opal.c index 16f90b1a750894..b2788ecad5b3cb 100644 --- a/drivers/i2c/busses/i2c-opal.c +++ b/drivers/i2c/busses/i2c-opal.c@@ -104,17 +104,6 @@ static int i2c_opal_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, req.buffer_ra = cpu_to_be64(__pa(msgs[0].buf)); break; case 2: - /* For two messages, we basically support only simple - * smbus transactions of a write plus a read. We might - * want to allow also two writes but we'd have to bounce - * the data into a single buffer. - */ - if ((msgs[0].flags & I2C_M_RD) || !(msgs[1].flags & I2C_M_RD)) - return -EOPNOTSUPP; - if (msgs[0].len > 4) - return -EOPNOTSUPP; - if (msgs[0].addr != msgs[1].addr) - return -EOPNOTSUPP; req.type = OPAL_I2C_SM_READ; req.addr = cpu_to_be16(msgs[0].addr); req.subaddr_sz = msgs[0].len;@@ -210,6 +199,16 @@ static const struct i2c_algorithm i2c_opal_algo = { .functionality = i2c_opal_func, }; +/* For two messages, we basically support only simple + * smbus transactions of a write plus a read. We might + * want to allow also two writes but we'd have to bounce + * the data into a single buffer. + */ +static struct i2c_adapter_quirks i2c_opal_quirks = { + .flags = I2C_AQ_COMB_WRITE_THEN_READ, + .max_comb_1st_msg_len = 4, +}; + static int i2c_opal_probe(struct platform_device *pdev) { struct i2c_adapter *adapter;@@ -232,6 +231,7 @@ static int i2c_opal_probe(struct platform_device *pdev) adapter->algo = &i2c_opal_algo; adapter->algo_data = (void *)(unsigned long)opal_id; + adapter->quirks = &i2c_opal_quirks; adapter->dev.parent = &pdev->dev; adapter->dev.of_node = of_node_get(pdev->dev.of_node); pname = of_get_property(pdev->dev.of_node, "ibm,port-name", NULL);