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| author | Heiner Kallweit <hkallweit1@gmail.com> | 2014-12-03 07:56:19 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2014-12-03 14:05:47 +0100 |
| commit | 75506d0e0084ee7f074be3c5da6d5de98ce347b6 (patch) | |
| tree | 61bb3916c2f3f04206bc0639e287b50ee23e2a0e /drivers/spi | |
| parent | spi: fsl-(e)spi: migrate to generic master queueing (diff) | |
| download | linux-75506d0e0084ee7f074be3c5da6d5de98ce347b6.tar.xz linux-75506d0e0084ee7f074be3c5da6d5de98ce347b6.zip | |
spi: fsl-espi: add (un)prepare_transfer_hardware calls to save power if SPI is not in use
Use (un)prepare_transfer_hardware calls to set fsl-espi to
low-power idle if not in use. Reference manual states:
"The eSPI is in a idle state and consumes minimal power.
The eSPI BRG is not functioning and the input clock is disabled"
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi-fsl-espi.c | 46 |
1 files changed, 35 insertions, 11 deletions
diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c index 90be6405e789..56cadf13519e 100644 --- a/drivers/spi/spi-fsl-espi.c +++ b/drivers/spi/spi-fsl-espi.c @@ -588,6 +588,38 @@ static void fsl_espi_remove(struct mpc8xxx_spi *mspi) iounmap(mspi->reg_base); } +static int fsl_espi_suspend(struct spi_master *master) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + u32 regval; + + mpc8xxx_spi = spi_master_get_devdata(master); + reg_base = mpc8xxx_spi->reg_base; + + regval = mpc8xxx_spi_read_reg(®_base->mode); + regval &= ~SPMODE_ENABLE; + mpc8xxx_spi_write_reg(®_base->mode, regval); + + return 0; +} + +static int fsl_espi_resume(struct spi_master *master) +{ + struct mpc8xxx_spi *mpc8xxx_spi; + struct fsl_espi_reg *reg_base; + u32 regval; + + mpc8xxx_spi = spi_master_get_devdata(master); + reg_base = mpc8xxx_spi->reg_base; + + regval = mpc8xxx_spi_read_reg(®_base->mode); + regval |= SPMODE_ENABLE; + mpc8xxx_spi_write_reg(®_base->mode, regval); + + return 0; +} + static struct spi_master * fsl_espi_probe(struct device *dev, struct resource *mem, unsigned int irq) { @@ -614,6 +646,8 @@ static struct spi_master * fsl_espi_probe(struct device *dev, master->setup = fsl_espi_setup; master->cleanup = fsl_espi_cleanup; master->transfer_one_message = fsl_espi_do_one_msg; + master->prepare_transfer_hardware = fsl_espi_resume; + master->unprepare_transfer_hardware = fsl_espi_suspend; mpc8xxx_spi = spi_master_get_devdata(master); mpc8xxx_spi->spi_remove = fsl_espi_remove; @@ -761,25 +795,15 @@ static int of_fsl_espi_remove(struct platform_device *dev) static int of_fsl_espi_suspend(struct device *dev) { struct spi_master *master = dev_get_drvdata(dev); - struct mpc8xxx_spi *mpc8xxx_spi; - struct fsl_espi_reg *reg_base; - u32 regval; int ret; - mpc8xxx_spi = spi_master_get_devdata(master); - reg_base = mpc8xxx_spi->reg_base; - ret = spi_master_suspend(master); if (ret) { dev_warn(dev, "cannot suspend master\n"); return ret; } - regval = mpc8xxx_spi_read_reg(®_base->mode); - regval &= ~SPMODE_ENABLE; - mpc8xxx_spi_write_reg(®_base->mode, regval); - - return 0; + return fsl_espi_suspend(master); } static int of_fsl_espi_resume(struct device *dev) |