| Message ID | 54725DE2.9090800@tul.cz (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Nov 23, 2014 at 11:21:22PM +0100, Petr Cvek wrote: > I created this patch by fixing both I2C controller and SCCB device, so > it seems I incorrectly used I2C_M_NOSTART instead I2C_M_STOP. Problem > with I2C_M_STOP is that it causes bus freeze when using userspace > utility "i2cget" on SCCB device (unfreeze can be done with i2c-pxa > module reload). But this can be probably repaired in i2cget. Please CC Jean Delvare, he maintains the I2C tools. > Patched kernel was from vanilla 3.18.0-rc5 commit fc14f9c1272f62c3e8d01300f52467c0d9af50f9 Thanks but all these paragraphs describing the updates should have gone below the "---" line. Your original commit message was more apropriate and should have stayed. > static u32 i2c_pxa_functionality(struct i2c_adapter *adap) > { > - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; > + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | > + I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART; Okay, so NOSTART was previously implemented but not advertised? Please update the commit log to say that this will be also fixed by your patch.
diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c index be671f7..f80df8f 100644 --- a/drivers/i2c/busses/i2c-pxa.c +++ b/drivers/i2c/busses/i2c-pxa.c @@ -885,7 +885,9 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr) return; /* ignore */ } - if (isr & ISR_BED) { + if ((isr & ISR_BED) && + (!((i2c->msg->flags & I2C_M_IGNORE_NAK) && + (isr & ISR_ACKNAK)))) { int ret = BUS_ERROR; /* @@ -919,12 +921,14 @@ static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr) icr |= ICR_ALDIE | ICR_TB; /* - * If this is the last byte of the last message, send - * a STOP. + * If this is the last byte of the last message or last byte + * of any message with I2C_M_STOP (e.g. SCCB), send a STOP. */ - if (i2c->msg_ptr == i2c->msg->len && - i2c->msg_idx == i2c->msg_num - 1) - icr |= ICR_STOP; + if ((i2c->msg_ptr == i2c->msg->len) && + ((i2c->msg->flags & I2C_M_STOP) || + (i2c->msg_idx == i2c->msg_num - 1))) + icr |= ICR_STOP; + } else if (i2c->msg_idx < i2c->msg_num - 1) { /* * Next segment of the message. @@ -1071,7 +1075,8 @@ static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num static u32 i2c_pxa_functionality(struct i2c_adapter *adap) { - return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; + return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | + I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART; } static const struct i2c_algorithm i2c_pxa_algorithm = {
I'm sorry for spacing, I didn't realize thunderbird automatically replaces tabs with spaces. Now it should be OK. I created this patch by fixing both I2C controller and SCCB device, so it seems I incorrectly used I2C_M_NOSTART instead I2C_M_STOP. Problem with I2C_M_STOP is that it causes bus freeze when using userspace utility "i2cget" on SCCB device (unfreeze can be done with i2c-pxa module reload). But this can be probably repaired in i2cget. Patched kernel was from vanilla 3.18.0-rc5 commit fc14f9c1272f62c3e8d01300f52467c0d9af50f9 Signed-off-by: Petr Cvek <petr.cvek@tul.cz> --- drivers/i2c/busses/i2c-pxa.c | 19 ++++++++++++------- 1 file changed, 12 insertions(+), 7 deletions(-)