Changes in v5:
---------------
- Added missing "Tested-By" tags.
Changes in v4:
---------------
- Extend comment (W1C vs. W0C)
Changes in v3:
---------------
- dedicated function for clearing an irq
Changes in v2:
---------------
- Don't accidently clear additional status flags on Vybrid
(reported by Uwe Kleine-Koenig)
If arbitration is lost, the master automatically changes to slave mode.
I2SR_IBB may or may not be reset by hardware. Raising a STOP condition
by resetting I2CR_MSTA has no effect and will not clear I2SR_IBB.
So calling i2c_imx_bus_busy() is not required and would busy-wait until
timeout.
Signed-off-by: Christian Eggers <[email protected]>
Tested (not extensively) on Vybrid VF500 (Toradex VF50):
Tested-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Oleksij Rempel <[email protected]>
Cc: [email protected] # Requires trivial backporting, simple remove
# the 3rd argument from the calls to
# i2c_imx_bus_busy().
---
drivers/i2c/busses/i2c-imx.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 69ce5eea9b5a..e98356f3db84 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -615,6 +615,8 @@ static void i2c_imx_stop(struct imx_i2c_struct *i2c_imx, bool atomic)
/* Stop I2C transaction */
dev_dbg(&i2c_imx->adapter.dev, "<%s>\n", __func__);
temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
temp &= ~(I2CR_MSTA | I2CR_MTX);
if (i2c_imx->dma)
temp &= ~I2CR_DMAEN;
@@ -778,9 +780,12 @@ static int i2c_imx_dma_read(struct imx_i2c_struct *i2c_imx,
*/
dev_dbg(dev, "<%s> clear MSTA\n", __func__);
temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
temp &= ~(I2CR_MSTA | I2CR_MTX);
imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
- i2c_imx_bus_busy(i2c_imx, 0, false);
+ if (!i2c_imx->stopped)
+ i2c_imx_bus_busy(i2c_imx, 0, false);
} else {
/*
* For i2c master receiver repeat restart operation like:
@@ -905,9 +910,12 @@ static int i2c_imx_read(struct imx_i2c_struct *i2c_imx, struct i2c_msg *msgs,
dev_dbg(&i2c_imx->adapter.dev,
"<%s> clear MSTA\n", __func__);
temp = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR);
+ if (!(temp & I2CR_MSTA))
+ i2c_imx->stopped = 1;
temp &= ~(I2CR_MSTA | I2CR_MTX);
imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2CR);
- i2c_imx_bus_busy(i2c_imx, 0, atomic);
+ if (!i2c_imx->stopped)
+ i2c_imx_bus_busy(i2c_imx, 0, atomic);
} else {
/*
* For i2c master receiver repeat restart operation like:
--
Christian Eggers
Embedded software developer
Arnold & Richter Cine Technik GmbH & Co. Betriebs KG
Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRA 57918
Persoenlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH
Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRB 54477
Geschaeftsfuehrer: Dr. Michael Neuhaeuser; Stephan Schenk; Walter Trauninger; Markus Zeiler
According to the "VFxxx Controller Reference Manual" (and the comment
block starting at line 97), Vybrid requires writing a one for clearing
an interrupt flag. Syncing the method for clearing I2SR_IIF in
i2c_imx_isr().
Signed-off-by: Christian Eggers <[email protected]>
Fixes: 4b775022f6fd ("i2c: imx: add struct to hold more configurable quirks")
Reviewed-by: Uwe Kleine-König <[email protected]>
Acked-by: Oleksij Rempel <[email protected]>
Cc: [email protected]
---
drivers/i2c/busses/i2c-imx.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c
index 0ab5381aa012..028f8a626410 100644
--- a/drivers/i2c/busses/i2c-imx.c
+++ b/drivers/i2c/busses/i2c-imx.c
@@ -412,6 +412,19 @@ static void i2c_imx_dma_free(struct imx_i2c_struct *i2c_imx)
dma->chan_using = NULL;
}
+static void i2c_imx_clear_irq(struct imx_i2c_struct *i2c_imx, unsigned int bits)
+{
+ unsigned int temp;
+
+ /*
+ * i2sr_clr_opcode is the value to clear all interrupts. Here we want to
+ * clear only <bits>, so we write ~i2sr_clr_opcode with just <bits>
+ * toggled. This is required because i.MX needs W0C and Vybrid uses W1C.
+ */
+ temp = ~i2c_imx->hwdata->i2sr_clr_opcode ^ bits;
+ imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
+}
+
static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool atomic)
{
unsigned long orig_jiffies = jiffies;
@@ -424,8 +437,7 @@ static int i2c_imx_bus_busy(struct imx_i2c_struct *i2c_imx, int for_busy, bool a
/* check for arbitration lost */
if (temp & I2SR_IAL) {
- temp &= ~I2SR_IAL;
- imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
+ i2c_imx_clear_irq(i2c_imx, I2SR_IAL);
return -EAGAIN;
}
@@ -469,7 +481,7 @@ static int i2c_imx_trx_complete(struct imx_i2c_struct *i2c_imx, bool atomic)
*/
readb_poll_timeout_atomic(addr, regval, regval & I2SR_IIF, 5, 1000 + 100);
i2c_imx->i2csr = regval;
- imx_i2c_write_reg(0, i2c_imx, IMX_I2C_I2SR);
+ i2c_imx_clear_irq(i2c_imx, I2SR_IIF | I2SR_IAL);
} else {
wait_event_timeout(i2c_imx->queue, i2c_imx->i2csr & I2SR_IIF, HZ / 10);
}
@@ -623,9 +635,7 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id)
if (temp & I2SR_IIF) {
/* save status register */
i2c_imx->i2csr = temp;
- temp &= ~I2SR_IIF;
- temp |= (i2c_imx->hwdata->i2sr_clr_opcode & I2SR_IIF);
- imx_i2c_write_reg(temp, i2c_imx, IMX_I2C_I2SR);
+ i2c_imx_clear_irq(i2c_imx, I2SR_IIF);
wake_up(&i2c_imx->queue);
return IRQ_HANDLED;
}
--
Christian Eggers
Embedded software developer
Arnold & Richter Cine Technik GmbH & Co. Betriebs KG
Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRA 57918
Persoenlich haftender Gesellschafter: Arnold & Richter Cine Technik GmbH
Sitz: Muenchen - Registergericht: Amtsgericht Muenchen - Handelsregisternummer: HRB 54477
Geschaeftsfuehrer: Dr. Michael Neuhaeuser; Stephan Schenk; Walter Trauninger; Markus Zeiler
On Fri, Oct 09, 2020 at 01:03:18PM +0200, Christian Eggers wrote:
> According to the "VFxxx Controller Reference Manual" (and the comment
> block starting at line 97), Vybrid requires writing a one for clearing
> an interrupt flag. Syncing the method for clearing I2SR_IIF in
> i2c_imx_isr().
>
> Signed-off-by: Christian Eggers <[email protected]>
> Fixes: 4b775022f6fd ("i2c: imx: add struct to hold more configurable quirks")
> Reviewed-by: Uwe Kleine-König <[email protected]>
> Acked-by: Oleksij Rempel <[email protected]>
> Cc: [email protected]
Applied to for-next, thanks!
On Fri, Oct 09, 2020 at 01:03:20PM +0200, Christian Eggers wrote:
> If arbitration is lost, the master automatically changes to slave mode.
> I2SR_IBB may or may not be reset by hardware. Raising a STOP condition
> by resetting I2CR_MSTA has no effect and will not clear I2SR_IBB.
>
> So calling i2c_imx_bus_busy() is not required and would busy-wait until
> timeout.
>
> Signed-off-by: Christian Eggers <[email protected]>
> Tested (not extensively) on Vybrid VF500 (Toradex VF50):
> Tested-by: Krzysztof Kozlowski <[email protected]>
> Acked-by: Oleksij Rempel <[email protected]>
> Cc: [email protected] # Requires trivial backporting, simple remove
> # the 3rd argument from the calls to
> # i2c_imx_bus_busy().
Applied to for-next, thanks!
> Changes in v5:
Changes in v6 were missing... Because patch 1 was updated, I reverted it
from for-current and will apply this series to for-next instead to give
it some more time for testing.
Hi Wolfram,
On Saturday, 10 October 2020, 13:06:58 CEST, Wolfram Sang wrote:
> > Changes in v5:
> Changes in v6 were missing... Because patch 1 was updated, I reverted it
> from for-current and will apply this series to for-next instead to give
> it some more time for testing.
can may patches be merged into for-current for -RC2 or RC3?
Best regards
Christian
On Saturday, 10 October 2020, 13:09:20 CET, Wolfram Sang wrote:
> On Fri, Oct 09, 2020 at 01:03:18PM +0200, Christian Eggers wrote:
> > According to the "VFxxx Controller Reference Manual" (and the comment
> > block starting at line 97), Vybrid requires writing a one for clearing
> > an interrupt flag. Syncing the method for clearing I2SR_IIF in
> > i2c_imx_isr().
> >
> > Signed-off-by: Christian Eggers <[email protected]>
> > Fixes: 4b775022f6fd ("i2c: imx: add struct to hold more configurable quirks")
> > Reviewed-by: Uwe Kleine-K?nig <[email protected]>
> > Acked-by: Oleksij Rempel <[email protected]>
> > Cc: [email protected]
>
> Applied to for-next, thanks!
>
I cannot find my patches in kernel/git/wsa/linux.git, branch "for-next".
Did they get lost?
regards
Christian
> > Applied to for-next, thanks!
> >
> I cannot find my patches in kernel/git/wsa/linux.git, branch "for-next".
> Did they get lost?
It seems like it :( I seem to have forgotten to push out and then
continued to to work on another computer with an older state. It is
highly embarassing but I can't find out what exactly happened. I hope I
didn't lose more patches. I am really sorry!
Pushed to for-next again.