[PATCH 0/4] Few spi_mpc83xx.c fixes and improvements

[PATCH 0/4] Few spi_mpc83xx.c fixes and improvements

[Anton Vorontsov]

Hi all,

These patches based on Linus' tree, as of today.

-- 
Anton Vorontsov
email: cbou@mail.ru
backup email: ya-cbou@yandex.ru
irc://irc.freenode.net/bd2

[PATCH 1/4] [POWERPC][SPI] spi_mpc83xx.c: should turn off SPI unit while switching any mode.

[Anton Vorontsov]

Documentation clearly states, that mode should not be changed
till SPMODE_ENABLE bit set. I've seen hangs w/o this patch.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
---
 drivers/spi/spi_mpc83xx.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 3295cfc..0b99fd9 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -176,6 +176,8 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
 			regval |= SPMODE_PM(pm);
 		}
 
+		/* Turn off SPI unit prior changing mode */
+		mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
 		mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
 		if (mpc83xx_spi->activate_cs)
 			mpc83xx_spi->activate_cs(spi->chip_select, pol);
@@ -249,6 +251,8 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 	regval &= 0xff0fffff;
 	regval |= SPMODE_LEN(bits_per_word);
 
+	/* Turn off SPI unit prior changing mode */
+	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
 	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval);
 
 	return 0;
-- 
1.5.0.6

Re: [spi-devel-general] [PATCH 1/4] [POWERPC][SPI] spi_mpc83xx.c: should turn off SPI unit while switching any mode.

[Kumar Gala]

On Jul 26, 2007, at 8:13 AM, Anton Vorontsov wrote:

> Documentation clearly states, that mode should not be changed
> till SPMODE_ENABLE bit set. I've seen hangs w/o this patch.

Out of interest what board/part do you see the hang on?

- k

Re: [spi-devel-general] [PATCH 1/4] [POWERPC][SPI] spi_mpc83xx.c: should turn off SPI unit while switching any mode.

[Anton Vorontsov]

On Fri, Jul 27, 2007 at 01:32:27AM -0500, Kumar Gala wrote:
>
> On Jul 26, 2007, at 8:13 AM, Anton Vorontsov wrote:
>
>> Documentation clearly states, that mode should not be changed
>> till SPMODE_ENABLE bit set. I've seen hangs w/o this patch.
>
> Out of interest what board/part do you see the hang on?

It's MPC8323E-RDB.

Using spidev_test utility:

root@10.0.0.99:~# ./a.out -D /dev/spidev1.0
spi mode: 0
bits per word: 8
max speed: Hz (kHz): 500000 (500)
...
root@10.0.0.99:~#


Then trying change bits per word to 32:

root@10.0.0.99:~# ./a.out -D /dev/spidev1.0 -b 32
spi mode: 0
bits per word: 32
max speed: Hz (kHz): 500000 (500)
<---- hang

Board is still alive, but SPI isn't.

Though, there are various steps to reproduce the same.
So SPI unit should be really turned off to change mode.

Thanks,

-- 
Anton Vorontsov
email: cbou@mail.ru
backup email: ya-cbou@yandex.ru
irc://irc.freenode.net/bd2

[PATCH 2/4] [POWERPC][SPI] spi_mpc83xx: get rid of magic numbers

[Anton Vorontsov]

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
---
 drivers/spi/spi_mpc83xx.c |    5 +++--
 1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 0b99fd9..e2d8dbc 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -153,7 +153,8 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
 			len = len - 1;
 
 		/* mask out bits we are going to set */
-		regval &= ~0x38ff0000;
+		regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH |
+			    SPMODE_LEN(0xF) | SPMODE_DIV16 | SPMODE_PM(0xF));
 
 		if (spi->mode & SPI_CPHA)
 			regval |= SPMODE_CP_BEGIN_EDGECLK;
@@ -248,7 +249,7 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 	regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
 
 	/* Mask out bits_per_wordgth */
-	regval &= 0xff0fffff;
+	regval &= ~SPMODE_LEN(0xF);
 	regval |= SPMODE_LEN(bits_per_word);
 
 	/* Turn off SPI unit prior changing mode */
-- 
1.5.0.6

[PATCH 3/4] [POWERPC][SPI] spi_mpc83xx: support for lsb mode switching

[Anton Vorontsov]

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
---
 drivers/spi/spi_mpc83xx.c |   13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index e2d8dbc..7e17c8b 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -154,12 +154,15 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
 
 		/* mask out bits we are going to set */
 		regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH |
-			    SPMODE_LEN(0xF) | SPMODE_DIV16 | SPMODE_PM(0xF));
+			    SPMODE_LEN(0xF) | SPMODE_DIV16 | SPMODE_PM(0xF) | \
+			    SPMODE_REV);
 
 		if (spi->mode & SPI_CPHA)
 			regval |= SPMODE_CP_BEGIN_EDGECLK;
 		if (spi->mode & SPI_CPOL)
 			regval |= SPMODE_CI_INACTIVEHIGH;
+		if (!(spi->mode & SPI_LSB_FIRST))
+			regval |= SPMODE_REV;
 
 		regval |= SPMODE_LEN(len);
 
@@ -248,9 +251,11 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 
 	regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
 
-	/* Mask out bits_per_wordgth */
-	regval &= ~SPMODE_LEN(0xF);
+	/* mask out bits we are going to set */
+	regval &= ~(SPMODE_LEN(0xF) | SPMODE_REV);
 	regval |= SPMODE_LEN(bits_per_word);
+	if (!(spi->mode & SPI_LSB_FIRST))
+		regval |= SPMODE_REV;
 
 	/* Turn off SPI unit prior changing mode */
 	mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
@@ -260,7 +265,7 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 }
 
 /* the spi->mode bits understood by this driver: */
-#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST)
 
 static int mpc83xx_spi_setup(struct spi_device *spi)
 {
-- 
1.5.0.6

[PATCH 4/4] [POWERPC][SPI] spi_mpc83xx: fix LSB mode shifts

[Anton Vorontsov]

spi_mpc83xx should use other shifts when running in QE+LSB mode.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
---
 drivers/spi/spi_mpc83xx.c |    8 ++++++++
 1 files changed, 8 insertions(+), 0 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 7e17c8b..458075a 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -237,6 +237,14 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
 	} else
 		return -EINVAL;
 
+	if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) {
+		mpc83xx_spi->tx_shift = 0;
+		if (bits_per_word <= 8)
+			mpc83xx_spi->rx_shift = 8;
+		else
+			mpc83xx_spi->rx_shift = 0;
+	}
+
 	/* nsecs = (clock period)/2 */
 	if (!hz)
 		hz = spi->max_speed_hz;
-- 
1.5.0.6

Re: [spi-devel-general] [PATCH 0/4] Few spi_mpc83xx.c fixes and improvements

[David Brownell]

On Thursday 26 July 2007, Anton Vorontsov wrote:
> Hi all,
> 
> These patches based on Linus' tree, as of today.

I don't know mpc83xx ... are there any PPC folk who can see
any reason not to just merge these patches?  They look OK
to me, but in this case that doesn't mean much.  :)

If I don't hear otherwise, I'll forward all four of these
patches upstream on Monday.

(Anton, thanks for these updates!)

- Dave

Re: [spi-devel-general] [PATCH 0/4] Few spi_mpc83xx.c fixes and improvements

[Kumar Gala]

On Jul 26, 2007, at 9:58 PM, David Brownell wrote:

> On Thursday 26 July 2007, Anton Vorontsov wrote:
>> Hi all,
>>
>> These patches based on Linus' tree, as of today.
>
> I don't know mpc83xx ... are there any PPC folk who can see
> any reason not to just merge these patches?  They look OK
> to me, but in this case that doesn't mean much.  :)
>
> If I don't hear otherwise, I'll forward all four of these
> patches upstream on Monday.
>
> (Anton, thanks for these updates!)

These all look good to me for upstream.

Acked-off-by: Kumar Gala <galak@kernel.crashing.org>

- k