| Message ID | 201306281144.34074.hartleys@visionengravers.com (mailing list archive) |
|---|---|
| State | Superseded, archived |
| Headers | show |
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 <hsweeten@visionengravers.com> > Cc: Ryan Mallon <rmallon@gmail.com> > Cc: Mika Westerberg <mika.westerberg@iki.fi> > Cc: Mark Brown <broonie@kernel.org> > Cc: Grant Likely <grant.likely@linaro.org> > --- > 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. ------------------------------------------------------------------------------ This SF.net email is sponsored by Windows: Build for Windows Store. http://p.sf.net/sfu/windows-dev2dev
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;
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 <hsweeten@visionengravers.com> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Mika Westerberg <mika.westerberg@iki.fi> Cc: Mark Brown <broonie@kernel.org> Cc: Grant Likely <grant.likely@linaro.org> --- drivers/spi/spi-ep93xx.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-)