From: Geert Uytterhoeven <geert+rene...@linux-m68k.org>
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 <takas...@ops.dti.ne.jp>.
Signed-off-by: Geert Uytterhoeven <geert+rene...@linux-m68k.org>
Cc: Takashi Yoshii <takas...@ops.dti.ne.jp>
---
drivers/spi/spi-sh-msiof.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)
diff --git a/drivers/spi/spi-sh-msiof.c b/drivers/spi/spi-sh-msiof.c
index 79e14586049b..92515c1ececa 100644
--- a/drivers/spi/spi-sh-msiof.c
+++ b/drivers/spi/spi-sh-msiof.c
@@ -445,6 +445,21 @@ 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);
@@ -470,8 +485,8 @@ 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)) {
@@ -758,7 +773,7 @@ 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;
--
1.7.9.5
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