diff options
author | Andreas Larsson <andreas@gaisler.com> | 2013-02-15 19:52:27 +0400 |
---|---|---|
committer | Grant Likely <grant.likely@secretlab.ca> | 2013-04-07 13:07:57 +0400 |
commit | 76a7498f691f4c315dba0747141eeee3ceb740dc (patch) | |
tree | 450b8f6c491a6801863767ea1d1e031476a6ee73 /drivers/spi | |
parent | 447b0c7b939f1d9e4024edf07a471ce7b1bcf002 (diff) | |
download | linux-76a7498f691f4c315dba0747141eeee3ceb740dc.tar.xz |
spi/spi-fsl-spi: Add support for gpio chipselects for GRLIB type cores
This relies upon of_spi_register_master to find out which gpios to use.
Acked-by: Anton Vorontsov <anton@enomsg.org>
Signed-off-by: Andreas Larsson <andreas@gaisler.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'drivers/spi')
-rw-r--r-- | drivers/spi/spi-fsl-lib.h | 1 | ||||
-rw-r--r-- | drivers/spi/spi-fsl-spi.c | 50 |
2 files changed, 46 insertions, 5 deletions
diff --git a/drivers/spi/spi-fsl-lib.h b/drivers/spi/spi-fsl-lib.h index d5c788b584df..52db6936778e 100644 --- a/drivers/spi/spi-fsl-lib.h +++ b/drivers/spi/spi-fsl-lib.h @@ -71,6 +71,7 @@ struct mpc8xxx_spi { #ifdef CONFIG_SPI_FSL_SPI int type; + int native_chipselects; u8 max_bits_per_word; void (*set_shifts)(u32 *rx_shift, u32 *tx_shift, diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c index 6846459e5c9d..14e202ee7036 100644 --- a/drivers/spi/spi-fsl-spi.c +++ b/drivers/spi/spi-fsl-spi.c @@ -456,12 +456,46 @@ static int fsl_spi_setup(struct spi_device *spi) return retval; } + if (mpc8xxx_spi->type == TYPE_GRLIB) { + if (gpio_is_valid(spi->cs_gpio)) { + int desel; + + retval = gpio_request(spi->cs_gpio, + dev_name(&spi->dev)); + if (retval) + return retval; + + desel = !(spi->mode & SPI_CS_HIGH); + retval = gpio_direction_output(spi->cs_gpio, desel); + if (retval) { + gpio_free(spi->cs_gpio); + return retval; + } + } else if (spi->cs_gpio != -ENOENT) { + if (spi->cs_gpio < 0) + return spi->cs_gpio; + return -EINVAL; + } + /* When spi->cs_gpio == -ENOENT, a hole in the phandle list + * indicates to use native chipselect if present, or allow for + * an always selected chip + */ + } + /* Initialize chipselect - might be active for SPI_CS_HIGH mode */ fsl_spi_chipselect(spi, BITBANG_CS_INACTIVE); return 0; } +static void fsl_spi_cleanup(struct spi_device *spi) +{ + struct mpc8xxx_spi *mpc8xxx_spi = spi_master_get_devdata(spi->master); + + if (mpc8xxx_spi->type == TYPE_GRLIB && gpio_is_valid(spi->cs_gpio)) + gpio_free(spi->cs_gpio); +} + static void fsl_spi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events) { struct fsl_spi_reg *reg_base = mspi->reg_base; @@ -529,9 +563,13 @@ static void fsl_spi_grlib_cs_control(struct spi_device *spi, bool on) u32 slvsel; u16 cs = spi->chip_select; - slvsel = mpc8xxx_spi_read_reg(®_base->slvsel); - slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs)); - mpc8xxx_spi_write_reg(®_base->slvsel, slvsel); + if (gpio_is_valid(spi->cs_gpio)) { + gpio_set_value(spi->cs_gpio, on); + } else if (cs < mpc8xxx_spi->native_chipselects) { + slvsel = mpc8xxx_spi_read_reg(®_base->slvsel); + slvsel = on ? (slvsel | (1 << cs)) : (slvsel & ~(1 << cs)); + mpc8xxx_spi_write_reg(®_base->slvsel, slvsel); + } } static void fsl_spi_grlib_probe(struct device *dev) @@ -550,11 +588,12 @@ static void fsl_spi_grlib_probe(struct device *dev) if (mbits) mpc8xxx_spi->max_bits_per_word = mbits + 1; - master->num_chipselect = 1; /* Allow for an always selected chip */ + mpc8xxx_spi->native_chipselects = 0; if (SPCAP_SSEN(capabilities)) { - master->num_chipselect = SPCAP_SSSZ(capabilities); + mpc8xxx_spi->native_chipselects = SPCAP_SSSZ(capabilities); mpc8xxx_spi_write_reg(®_base->slvsel, 0xffffffff); } + master->num_chipselect = mpc8xxx_spi->native_chipselects; pdata->cs_control = fsl_spi_grlib_cs_control; } @@ -581,6 +620,7 @@ static struct spi_master * fsl_spi_probe(struct device *dev, goto err_probe; master->setup = fsl_spi_setup; + master->cleanup = fsl_spi_cleanup; mpc8xxx_spi = spi_master_get_devdata(master); mpc8xxx_spi->spi_do_one_msg = fsl_spi_do_one_msg; |