3 files changed, 33 insertions, 1 deletions

diff --git a/drivers/spi/spi-bitbang.c b/drivers/spi/spi-bitbang.c
index 76f1b534bdd7..f29176000b8d 100644
--- a/drivers/spi/spi-bitbang.c
+++ b/drivers/spi/spi-bitbang.c
@@ -243,7 +243,23 @@ static int spi_bitbang_bufs(struct spi_device *spi, struct spi_transfer *t)
 {
         struct spi_bitbang_cs   *cs = spi->controller_state;
         unsigned                nsecs = cs->nsecs;
+        struct spi_bitbang      *bitbang;
+
+        bitbang = spi_master_get_devdata(spi->master);
+        if (bitbang->set_line_direction) {
+                int err;
 
+                err = bitbang->set_line_direction(spi, !!(t->tx_buf));
+                if (err < 0)
+                        return err;
+        }
+
+        if (spi->mode & SPI_3WIRE) {
+                unsigned flags;
+
+                flags = t->tx_buf ? SPI_MASTER_NO_RX : SPI_MASTER_NO_TX;
+                return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, flags);
+        }
         return cs->txrx_bufs(spi, cs->txrx_word, nsecs, t, 0);
 }
 
diff --git a/drivers/spi/spi-gpio.c b/drivers/spi/spi-gpio.c
index be68298cbd9c..0626e6e3ea0c 100644
--- a/drivers/spi/spi-gpio.c
+++ b/drivers/spi/spi-gpio.c
@@ -121,7 +121,10 @@ static inline int getmiso(const struct spi_device *spi)
 {
         struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
 
-        return !!gpiod_get_value_cansleep(spi_gpio->miso);
+        if (spi->mode & SPI_3WIRE)
+                return !!gpiod_get_value_cansleep(spi_gpio->mosi);
+        else
+                return !!gpiod_get_value_cansleep(spi_gpio->miso);
 }
 
 /*
@@ -250,6 +253,16 @@ static int spi_gpio_setup(struct spi_device *spi)
         return status;
 }
 
+static int spi_gpio_set_direction(struct spi_device *spi, bool output)
+{
+        struct spi_gpio *spi_gpio = spi_to_spi_gpio(spi);
+
+        if (output)
+                return gpiod_direction_output(spi_gpio->mosi, 1);
+        else
+                return gpiod_direction_input(spi_gpio->mosi);
+}
+
 static void spi_gpio_cleanup(struct spi_device *spi)
 {
         spi_bitbang_cleanup(spi);
@@ -395,6 +408,7 @@ static int spi_gpio_probe(struct platform_device *pdev)
                 return status;
 
         master->bits_per_word_mask = SPI_BPW_RANGE_MASK(1, 32);
+        master->mode_bits = SPI_3WIRE | SPI_CPHA | SPI_CPOL;
         master->flags = master_flags;
         master->bus_num = pdev->id;
         /* The master needs to think there is a chipselect even if not connected */
@@ -407,6 +421,7 @@ static int spi_gpio_probe(struct platform_device *pdev)
 
         spi_gpio->bitbang.master = master;
         spi_gpio->bitbang.chipselect = spi_gpio_chipselect;
+        spi_gpio->bitbang.set_line_direction = spi_gpio_set_direction;
 
         if ((master_flags & (SPI_MASTER_NO_TX | SPI_MASTER_NO_RX)) == 0) {
                 spi_gpio->bitbang.txrx_word[SPI_MODE_0] = spi_gpio_txrx_word_mode0;
diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h
index 5847f00ef9cf..b7e021b274dc 100644
--- a/include/linux/spi/spi_bitbang.h
+++ b/include/linux/spi/spi_bitbang.h
@@ -31,6 +31,7 @@ struct spi_bitbang {
         u32     (*txrx_word[4])(struct spi_device *spi,
                         unsigned nsecs,
                         u32 word, u8 bits, unsigned flags);
+        int     (*set_line_direction)(struct spi_device *spi, bool output);
 };
 
 /* you can call these default bitbang->master methods from your custom