This value is only needed to set the bits per word for each transfer
of a message. There is no reason to set the value in ep93xx_spi_enable()
because ep93xx_spi_process_transfer() sets it again for each transfer.
Just pass the t->bits_per_word directly to ep93xx_spi_chip_setup() in
ep93xx_spi_process_transfer() and remove 'dss' from the per chip private
data.
Signed-off-by: H Hartley Sweeten <[email protected]>
Cc: Ryan Mallon <[email protected]>
Cc: Mika Westerberg <[email protected]>
Cc: Mark Brown <[email protected]>
Cc: Grant Likely <[email protected]>
---
drivers/spi/spi-ep93xx.c | 20 +++++++-------------
1 file changed, 7 insertions(+), 13 deletions(-)
diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c
index 4fab3bb..cb22c89 100644
--- a/drivers/spi/spi-ep93xx.c
+++ b/drivers/spi/spi-ep93xx.c
@@ -140,7 +140,6 @@ struct ep93xx_spi {
* @rate: max rate in hz this chip supports
* @div_cpsr: cpsr (pre-scaler) divider
* @div_scr: scr divider
- * @dss: bits per word (4 - 16 bits)
* @ops: private chip operations
*
* This structure is used to store hardware register specific settings for each
@@ -152,13 +151,9 @@ struct ep93xx_spi_chip {
unsigned long rate;
u8 div_cpsr;
u8 div_scr;
- u8 dss;
struct ep93xx_spi_chip_ops *ops;
};
-/* converts bits per word to CR0.DSS value */
-#define bits_per_word_to_dss(bpw) ((bpw) - 1)
-
static int ep93xx_spi_enable(const struct ep93xx_spi *espi)
{
u8 regval;
@@ -308,8 +303,6 @@ static int ep93xx_spi_setup(struct spi_device *spi)
chip->rate = spi->max_speed_hz;
}
- chip->dss = bits_per_word_to_dss(spi->bits_per_word);
-
ep93xx_spi_cs_control(spi, false);
return 0;
}
@@ -386,22 +379,25 @@ static void ep93xx_spi_cleanup(struct spi_device *spi)
* ep93xx_spi_chip_setup() - configures hardware according to given @chip
* @espi: ep93xx SPI controller struct
* @chip: chip specific settings
+ * @bits_per_word: transfer bits_per_word
*
* This function sets up the actual hardware registers with settings given in
* @chip. Note that no validation is done so make sure that callers validate
* settings before calling this.
*/
static void ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
- const struct ep93xx_spi_chip *chip)
+ const struct ep93xx_spi_chip *chip,
+ u8 bits_per_word)
{
u16 cr0;
cr0 = chip->div_scr << SSPCR0_SCR_SHIFT;
cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT;
- cr0 |= chip->dss;
+ cr0 |= (bits_per_word - 1);
dev_dbg(&espi->pdev->dev, "setup: mode %d, cpsr %d, scr %d, dss %d\n",
- chip->spi->mode, chip->div_cpsr, chip->div_scr, chip->dss);
+ chip->spi->mode, chip->div_cpsr, chip->div_scr,
+ bits_per_word - 1);
dev_dbg(&espi->pdev->dev, "setup: cr0 %#x", cr0);
writeb(chip->div_cpsr, espi->regs_base + SSPCPSR);
@@ -688,9 +684,7 @@ static void ep93xx_spi_process_transfer(struct ep93xx_spi *espi,
return;
}
- chip->dss = bits_per_word_to_dss(t->bits_per_word);
-
- ep93xx_spi_chip_setup(espi, chip);
+ ep93xx_spi_chip_setup(espi, chip, t->bits_per_word);
espi->word_xfer = (t->bits_per_word > 8) ? true : false;
espi->rx = 0;
--
1.8.1.4
On Fri, Jun 28, 2013 at 11:44:33AM -0700, H Hartley Sweeten wrote:
> This value is only needed to set the bits per word for each transfer
> of a message. There is no reason to set the value in ep93xx_spi_enable()
> because ep93xx_spi_process_transfer() sets it again for each transfer.
>
> Just pass the t->bits_per_word directly to ep93xx_spi_chip_setup() in
> ep93xx_spi_process_transfer() and remove 'dss' from the per chip private
> data.
>
> Signed-off-by: H Hartley Sweeten <[email protected]>
> Cc: Ryan Mallon <[email protected]>
> Cc: Mika Westerberg <[email protected]>
> Cc: Mark Brown <[email protected]>
> Cc: Grant Likely <[email protected]>
> ---
> drivers/spi/spi-ep93xx.c | 20 +++++++-------------
> 1 file changed, 7 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/spi/spi-ep93xx.c b/drivers/spi/spi-ep93xx.c
> index 4fab3bb..cb22c89 100644
> --- a/drivers/spi/spi-ep93xx.c
> +++ b/drivers/spi/spi-ep93xx.c
> @@ -140,7 +140,6 @@ struct ep93xx_spi {
> * @rate: max rate in hz this chip supports
> * @div_cpsr: cpsr (pre-scaler) divider
> * @div_scr: scr divider
> - * @dss: bits per word (4 - 16 bits)
> * @ops: private chip operations
> *
> * This structure is used to store hardware register specific settings for each
> @@ -152,13 +151,9 @@ struct ep93xx_spi_chip {
> unsigned long rate;
> u8 div_cpsr;
> u8 div_scr;
> - u8 dss;
> struct ep93xx_spi_chip_ops *ops;
> };
>
> -/* converts bits per word to CR0.DSS value */
> -#define bits_per_word_to_dss(bpw) ((bpw) - 1)
I think you should keep this macro...
> -
> static int ep93xx_spi_enable(const struct ep93xx_spi *espi)
> {
> u8 regval;
> @@ -308,8 +303,6 @@ static int ep93xx_spi_setup(struct spi_device *spi)
> chip->rate = spi->max_speed_hz;
> }
>
> - chip->dss = bits_per_word_to_dss(spi->bits_per_word);
> -
> ep93xx_spi_cs_control(spi, false);
> return 0;
> }
> @@ -386,22 +379,25 @@ static void ep93xx_spi_cleanup(struct spi_device *spi)
> * ep93xx_spi_chip_setup() - configures hardware according to given @chip
> * @espi: ep93xx SPI controller struct
> * @chip: chip specific settings
> + * @bits_per_word: transfer bits_per_word
> *
> * This function sets up the actual hardware registers with settings given in
> * @chip. Note that no validation is done so make sure that callers validate
> * settings before calling this.
> */
> static void ep93xx_spi_chip_setup(const struct ep93xx_spi *espi,
> - const struct ep93xx_spi_chip *chip)
> + const struct ep93xx_spi_chip *chip,
> + u8 bits_per_word)
> {
> u16 cr0;
>
> cr0 = chip->div_scr << SSPCR0_SCR_SHIFT;
> cr0 |= (chip->spi->mode & (SPI_CPHA|SPI_CPOL)) << SSPCR0_MODE_SHIFT;
> - cr0 |= chip->dss;
> + cr0 |= (bits_per_word - 1);
... and use it here. It makes things less confusing, at least to me.