diff options
| author | Geert Uytterhoeven <geert+renesas@linux-m68k.org> | 2014-02-20 15:43:04 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@linaro.org> | 2014-02-22 04:11:12 +0100 |
| commit | 8d19534a8d539bb2e598e56e017a423f205e909e (patch) | |
| tree | 3bfccab6e9f7fa585b31f88bec1cec8ebe19e98e /drivers/spi/spi-sh-msiof.c | |
| parent | spi: sh-msiof: Add more register documentation (diff) | |
| download | linux-8d19534a8d539bb2e598e56e017a423f205e909e.tar.xz linux-8d19534a8d539bb2e598e56e017a423f205e909e.zip | |
spi: sh-msiof: Use the core cs_gpio field, and make it optional
In current implementation, CS is controlled by GPIO, which is passed
through spi->controller_data. However, the MSIOF HW module has a function
to output CS by itself, which is already enabled and actual switch will be
done by pinmux.
Store the GPIO number in the core cs_gpio field, and ignore it if it is
an invalid (negative) GPIO number.
Loosely based on a patch from Takashi Yoshii <takasi-y@ops.dti.ne.jp>.
Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Diffstat (limited to 'drivers/spi/spi-sh-msiof.c')
| -rw-r--r-- | drivers/spi/spi-sh-msiof.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c index 7acbc4052757..6e2ba62ceb63 100644 --- a/drivers/spi/spi-sh-msiof.c +++ b/drivers/spi/spi-sh-msiof.c @@ -446,6 +446,21 @@ static int sh_msiof_spi_setup_transfer(struct spi_device *spi, return spi_bitbang_setup_transfer(spi, t); } +static int sh_msiof_spi_setup(struct spi_device *spi) +{ + struct device_node *np = spi->master->dev.of_node; + + if (!np) { + /* + * Use spi->controller_data for CS (same strategy as spi_gpio), + * if any. otherwise let HW control CS + */ + spi->cs_gpio = (uintptr_t)spi->controller_data; + } + + return spi_bitbang_setup(spi); +} + static void sh_msiof_spi_chipselect(struct spi_device *spi, int is_on) { struct sh_msiof_spi_priv *p = spi_master_get_devdata(spi->master); @@ -471,8 +486,8 @@ static void sh_msiof_spi_chipselect(struct spi_device *spi, int is_on) !!(spi->mode & SPI_CS_HIGH)); } - /* use spi->controller data for CS (same strategy as spi_gpio) */ - gpio_set_value((uintptr_t)spi->controller_data, value); + if (spi->cs_gpio >= 0) + gpio_set_value(spi->cs_gpio, value); if (is_on == BITBANG_CS_INACTIVE) { if (test_and_clear_bit(0, &p->flags)) { @@ -759,7 +774,7 @@ static int sh_msiof_spi_probe(struct platform_device *pdev) master->bus_num = pdev->id; master->dev.of_node = pdev->dev.of_node; master->num_chipselect = p->info->num_chipselect; - master->setup = spi_bitbang_setup; + master->setup = sh_msiof_spi_setup; master->cleanup = spi_bitbang_cleanup; p->bitbang.master = master; |