On Fri, Aug 03, 2007 at 04:29:48AM -0500, Kumar Gala wrote:
>
> On Aug 2, 2007, at 4:47 PM, David Brownell wrote:
>
> > On Thursday 02 August 2007, Anton Vorontsov wrote:
> >> Probably someday mpc83xx_spi->sysclk should be renamed to
> >> mpc83xx_spi->spiclk to be less confusing.
> >
> > Why not "today", with this patch? That would fix some of
> > the root cause of this bug...
>
> I'm fine with this as well. I just called it sysclk to start with
> since when I wrote the driver it was just for the MPC834x.
Ok, great.
Now I think that `spiclk' is the bad name either, because it's output
clock of the spi unit. `spibrg' should be the best name for this,
as it's input clock to the SPI unit. Patch below.
- - - -
From: Anton Vorontsov <[EMAIL PROTECTED]>
Subject: [PATCH] spi_mpc83xx: for SPI in QE spibrg's input is sysclk/2
For MPC8349E input to SPIBRG is SYSCLK, but it's SYSCLK/2 for
MPC8323E (SPI in QE).
Also mpc83xx_spi->sysclk renamed to mpc83xx_spi->spibrg.
Signed-off-by: Anton Vorontsov <[EMAIL PROTECTED]>
---
drivers/spi/spi_mpc83xx.c | 20 ++++++++++++--------
1 files changed, 12 insertions(+), 8 deletions(-)
diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 0c16a2b..446b624 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -86,7 +86,7 @@ struct mpc83xx_spi {
unsigned nsecs; /* (clock cycle time)/2 */
- u32 sysclk;
+ u32 spibrg; /* SPIBRG input clock */
u32 rx_shift; /* RX data reg shift when in qe mode */
u32 tx_shift; /* TX data reg shift when in qe mode */
@@ -169,17 +169,17 @@ static void mpc83xx_spi_chipselect(struct spi_device
*spi, int value)
regval |= SPMODE_LEN(len);
- if ((mpc83xx_spi->sysclk / spi->max_speed_hz) >= 64) {
- u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 64);
+ if ((mpc83xx_spi->spibrg / spi->max_speed_hz) >= 64) {
+ u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 64);
if (pm > 0x0f) {
- printk(KERN_WARNING "MPC83xx SPI: SPICLK can't
be less then a SYSCLK/1024!\n"
- "Requested SPICLK is %d Hz.
Will use %d Hz instead.\n",
- spi->max_speed_hz,
mpc83xx_spi->sysclk / 1024);
+ dev_warn(&spi->dev, "Requested speed is too "
+ "low: %d Hz. Will use %d Hz instead.\n",
+ spi->max_speed_hz, mpc83xx_spi->spibrg
/ 1024);
pm = 0x0f;
}
regval |= SPMODE_PM(pm) | SPMODE_DIV16;
} else {
- u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 4);
+ u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4);
regval |= SPMODE_PM(pm);
}
@@ -429,13 +429,17 @@ static int __init mpc83xx_spi_probe(struct
platform_device *dev)
mpc83xx_spi->bitbang.chipselect = mpc83xx_spi_chipselect;
mpc83xx_spi->bitbang.setup_transfer = mpc83xx_spi_setup_transfer;
mpc83xx_spi->bitbang.txrx_bufs = mpc83xx_spi_bufs;
- mpc83xx_spi->sysclk = pdata->sysclk;
mpc83xx_spi->activate_cs = pdata->activate_cs;
mpc83xx_spi->deactivate_cs = pdata->deactivate_cs;
mpc83xx_spi->qe_mode = pdata->qe_mode;
mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8;
mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8;
+ if (mpc83xx_spi->qe_mode)
+ mpc83xx_spi->spibrg = pdata->sysclk / 2;
+ else
+ mpc83xx_spi->spibrg = pdata->sysclk;
+
mpc83xx_spi->rx_shift = 0;
mpc83xx_spi->tx_shift = 0;
if (mpc83xx_spi->qe_mode) {
--
1.5.0.6
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