spi: omap2-mcspi: disable other channels CHCONF_FORCE in prepare_message
PATCH v2 1/1 spi: omap2-mcspi: disable other channels CHCONF_FORCE in prepare_message
Since the "Switch driver to use transfer_one" change, the cs_change behavior has changed and a channel chip select can still be asserted when changing channel from a previous last transfer in a message having the cs_change attribute.
Since there is no sense having multiple chip select being asserted at the same time, disable all the remaining forced chip selects in a the prepare_message called right before a spi_transfer_one_message call. It ignores the current channel configuration in order to keep the possibility to leave the chip select asserted between messages.
It fixes this bug on a DM8168 SoC ES2.1 Soc and an OMAP4 ES2.1 SoC. It was hanging all the other channels transfers when a CHCONF_FORCE is present on the wrong channel.
--- drivers/spi/spi-omap2-mcspi.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)
Test code can be found on :
http://pastebin.com/0SrqbGP7
Before patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start [ 59.790069] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 60.798736] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 61.802032] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 62.807525] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 63.812042] spidev spi1.1: TXS timed out spidev1.1 ioctl success ...
After Patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success ...
v2: uses msg to leave asserted chip select for the current channel
This is a patch RFC following the bug report :
'McSPI hangs with cs_change after "Switch driver to use transfer_one" change'
http://permalink.gmane.org/gmane.linux.kernel/2056841
drivers/spi/spi-omap2-mcspi.c +28 -0
@@ -1217,6 +1217,33 @@ out:return status; } +static int omap2_mcspi_prepare_message (struct spi_master *master, +struct spi_message *msg) +{ +struct omap2_mcspi *mcspi =spi_master_get_devdata (master); +struct omap2_mcspi_regs *ctx = &mcspi->ctx; +struct omap2_mcspi_cs *cs; + +/* Only a single channel can have the FORCE bit enabled +* in its chconf0 register. +* Scan all channels and disable them except the current one. +* A FORCE can remain from a last transfer having cs_change enabled +*/ +list_for_each_entry (cs, &ctx->cs, node) { +if (msg->spi->controller_state == cs) +continue ; + +if ((cs->chconf0 &OMAP2_MCSPI_CHCONF_FORCE )) { + cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE ; +writel_relaxed (cs->chconf0, + cs->base +OMAP2_MCSPI_CHCONF0 ); +readl_relaxed (cs->base +OMAP2_MCSPI_CHCONF0 ); + } + } + +return 0 ; +} +static int omap2_mcspi_transfer_one (struct spi_master *master,struct spi_device *spi,struct spi_transfer *t) {
@@ -1344,6 +1371,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev) master->bits_per_word_mask =SPI_BPW_RANGE_MASK (4 ,32 ); master->setup = omap2_mcspi_setup; master->auto_runtime_pm = true; + master->prepare_message = omap2_mcspi_prepare_message; master->transfer_one = omap2_mcspi_transfer_one; master->set_cs = omap2_mcspi_set_cs; master->cleanup = omap2_mcspi_cleanup;
Signature · 1 line
1.9.1
Quoted 70 lines · Neil Armstrong
Since the "Switch driver to use
transfer_one" change, thecs_changebehavior has changed and a channel chip select can still be asserted when changing channel from a previous last transfer in a message having thecs_changeattribute.Since there is no sense having multiple chip select being asserted at the same time, disable all the remaining forced chip selects in a the
prepare_messagecalled right before aspi_transfer_one_messagecall. It ignores the current channel configuration in order to keep the possibility to leave the chip select asserted between messages.It fixes this bug on a DM8168 SoC ES2.1 Soc and an OMAP4 ES2.1 SoC. It was hanging all the other channels transfers when a
CHCONF_FORCEis present on the wrong channel.Fixes b28cb9414db9 ("spi: omap2-mcspi: Switch driver to use transfer_one")Signed-off-by Neil Armstrong <[email protected]>--- drivers/spi/spi-omap2-mcspi.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)Test code can be found on :
http://pastebin.com/0SrqbGP7Before patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start [ 59.790069] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 60.798736] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 61.802032] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 62.807525] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 63.812042] spidev spi1.1: TXS timed out spidev1.1 ioctl success ...After Patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success ...v2: uses msg to leave asserted chip select for the current channel
This is a patch RFC following the bug report :
'McSPI hangs withcs_changeafter "Switch driver to usetransfer_one" change'
http://permalink.gmane.org/gmane.linux.kernel/2056841drivers/spi/spi-omap2-mcspi.c +0
-0
drivers/spi/spi-omap2-mcspi.c out: · line 1226
Quoted 10 lines
drivers/spi/spi-omap2-mcspi.c +7
-0@@ -1217,6 +1217,33 @@ out:return status; } +static int omap2_mcspi_prepare_message (struct spi_master *master, +struct spi_message *msg) +{ +struct omap2_mcspi *mcspi =spi_master_get_devdata (master); +struct omap2_mcspi_regs *ctx = &mcspi->ctx; +struct omap2_mcspi_cs *cs; +
Do we need the pm_runtime_get_sync code here?
See previous commit.
Quoted 34 lines
drivers/spi/spi-omap2-mcspi.c +21
-0+/* Only a single channel can have the FORCE bit enabled +* in its chconf0 register. +* Scan all channels and disable them except the current one. +* A FORCE can remain from a last transfer having cs_change enabled +*/ +list_for_each_entry (cs, &ctx->cs, node) { +if (msg->spi->controller_state == cs) +continue ; + +if ((cs->chconf0 &OMAP2_MCSPI_CHCONF_FORCE )) { + cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE ; +writel_relaxed (cs->chconf0, + cs->base +OMAP2_MCSPI_CHCONF0 ); +readl_relaxed (cs->base +OMAP2_MCSPI_CHCONF0 ); + } + } + +return 0 ; +} +static int omap2_mcspi_transfer_one (struct spi_master *master,struct spi_device *spi,struct spi_transfer *t) {@@ -1344,6 +1371,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev) master->bits_per_word_mask =SPI_BPW_RANGE_MASK (4 ,32 ); master->setup = omap2_mcspi_setup; master->auto_runtime_pm = true; + master->prepare_message = omap2_mcspi_prepare_message; master->transfer_one = omap2_mcspi_transfer_one; master->set_cs = omap2_mcspi_set_cs; master->cleanup = omap2_mcspi_cleanup;Signature · 1 line
1.9.1
Quoted 74 lines · Michael Welling
Quoted 73 lines · Neil Armstrong
Since the "Switch driver to use
transfer_one" change, thecs_changebehavior has changed and a channel chip select can still be asserted when changing channel from a previous last transfer in a message having thecs_changeattribute.Since there is no sense having multiple chip select being asserted at the same time, disable all the remaining forced chip selects in a the
prepare_messagecalled right before aspi_transfer_one_messagecall. It ignores the current channel configuration in order to keep the possibility to leave the chip select asserted between messages.It fixes this bug on a DM8168 SoC ES2.1 Soc and an OMAP4 ES2.1 SoC. It was hanging all the other channels transfers when a
CHCONF_FORCEis present on the wrong channel.Fixes b28cb9414db9 ("spi: omap2-mcspi: Switch driver to use transfer_one")--- drivers/spi/spi-omap2-mcspi.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)Test code can be found on :
http://pastebin.com/0SrqbGP7Before patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start [ 59.790069] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 60.798736] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 61.802032] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 62.807525] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 63.812042] spidev spi1.1: TXS timed out spidev1.1 ioctl success ...After Patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success ...v2: uses msg to leave asserted chip select for the current channel
This is a patch RFC following the bug report :
'McSPI hangs withcs_changeafter "Switch driver to usetransfer_one" change'
http://permalink.gmane.org/gmane.linux.kernel/2056841drivers/spi/spi-omap2-mcspi.c +0
-0@@ -1217,6 +1217,33 @@ out:return status; }
Quoted 11 lines
drivers/spi/spi-omap2-mcspi.c out: · line 1226
Quoted 7 lines
drivers/spi/spi-omap2-mcspi.c +7
-0+static int omap2_mcspi_prepare_message (struct spi_master *master, +struct spi_message *msg) +{ +struct omap2_mcspi *mcspi =spi_master_get_devdata (master); +struct omap2_mcspi_regs *ctx = &mcspi->ctx; +struct omap2_mcspi_cs *cs; +Do we need the
pm_runtime_get_synccode here?
See previous commit.
I checked and prepare_message is only called after pm_rumtime_get_sync in __spi_pump_messages()
Neil
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Michael Welling
Reviewed-byQuoted 87 lines · Neil Armstrong
Quoted 74 lines · Michael Welling
Quoted 73 lines · Neil Armstrong
Since the "Switch driver to use
transfer_one" change, thecs_changebehavior has changed and a channel chip select can still be asserted when changing channel from a previous last transfer in a message having thecs_changeattribute.Since there is no sense having multiple chip select being asserted at the same time, disable all the remaining forced chip selects in a the
prepare_messagecalled right before aspi_transfer_one_messagecall. It ignores the current channel configuration in order to keep the possibility to leave the chip select asserted between messages.It fixes this bug on a DM8168 SoC ES2.1 Soc and an OMAP4 ES2.1 SoC. It was hanging all the other channels transfers when a
CHCONF_FORCEis present on the wrong channel.Fixes b28cb9414db9 ("spi: omap2-mcspi: Switch driver to use transfer_one")Signed-off-by Neil Armstrong <[email protected]>--- drivers/spi/spi-omap2-mcspi.c | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+)Test code can be found on :
http://pastebin.com/0SrqbGP7Before patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start [ 59.790069] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 60.798736] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 61.802032] spidev spi1.1: TXS timed out spidev1.1 ioctl success cs_change_command() start [ 62.807525] spidev spi1.3: RXS timed out spidev1.3 ioctl success no_dma_command() start [ 63.812042] spidev spi1.1: TXS timed out spidev1.1 ioctl success ...After Patch :
# ./test_spi cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success no_dma_command() start spidev1.1 ioctl success cs_change_command() start spidev1.3 ioctl success ...v2: uses msg to leave asserted chip select for the current channel
This is a patch RFC following the bug report :
'McSPI hangs withcs_changeafter "Switch driver to usetransfer_one" change'
http://permalink.gmane.org/gmane.linux.kernel/2056841drivers/spi/spi-omap2-mcspi.c +0
-0@@ -1217,6 +1217,33 @@ out:return status; }Quoted 11 lines
drivers/spi/spi-omap2-mcspi.c out: · line 1226
Quoted 7 lines
drivers/spi/spi-omap2-mcspi.c +7
-0+static int omap2_mcspi_prepare_message (struct spi_master *master, +struct spi_message *msg) +{ +struct omap2_mcspi *mcspi =spi_master_get_devdata (master); +struct omap2_mcspi_regs *ctx = &mcspi->ctx; +struct omap2_mcspi_cs *cs; +Do we need the
pm_runtime_get_synccode here?
See previous commit.
Quoted 1 line
I checked and
prepare_messageis only called afterpm_rumtime_get_syncin__spi_pump_messages()
Okay, I see it now.
Quoted 2 lines
Neil