spi: move common spi_setup() functionality into core

Start moving some spi_setup() functionality into the SPI core from the
various spi_master controller drivers:

 - Make that function stop being an inline;

 - Move two common idioms from drivers into that new function:
    * Default bits_per_word to 8 if that field isn't set
    * Issue a standardized dev_dbg() message

This is a net minor source code shrink, and supports enhancments found in
some follow-up patches.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

14 files changed, 60 insertions, 56 deletions

diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c
index 12e443cc4ac9..9f9ff3af72d7 100644
--- a/drivers/spi/atmel_spi.c
+++ b/drivers/spi/atmel_spi.c
@@ -555,8 +555,6 @@ static int atmel_spi_setup(struct spi_device *spi)
                 return -EINVAL;
         }
 
-        if (bits == 0)
-                bits = 8;
         if (bits < 8 || bits > 16) {
                 dev_dbg(&spi->dev,
                                 "setup: invalid bits_per_word %u (8 to 16)\n",
diff --git a/drivers/spi/au1550_spi.c b/drivers/spi/au1550_spi.c
index b02f25c702fd..6a407e60f05b 100644
--- a/drivers/spi/au1550_spi.c
+++ b/drivers/spi/au1550_spi.c
@@ -291,8 +291,6 @@ static int au1550_spi_setup(struct spi_device *spi)
 {
         struct au1550_spi *hw = spi_master_get_devdata(spi->master);
 
-        if (spi->bits_per_word == 0)
-                spi->bits_per_word = 8;
         if (spi->bits_per_word < 4 || spi->bits_per_word > 24) {
                 dev_err(&spi->dev, "setup: invalid bits_per_word=%d\n",
                         spi->bits_per_word);
diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c
index d6d0c5d241ce..b4f3b753d0f4 100644
--- a/drivers/spi/omap2_mcspi.c
+++ b/drivers/spi/omap2_mcspi.c
@@ -619,9 +619,7 @@ static int omap2_mcspi_setup(struct spi_device *spi)
                 return -EINVAL;
         }
 
-        if (spi->bits_per_word == 0)
-                spi->bits_per_word = 8;
-        else if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
+        if (spi->bits_per_word < 4 || spi->bits_per_word > 32) {
                 dev_dbg(&spi->dev, "setup: unsupported %d bit words\n",
                         spi->bits_per_word);
                 return -EINVAL;
diff --git a/drivers/spi/omap_uwire.c b/drivers/spi/omap_uwire.c
index fe8b9ac0ccef..747d29be45d5 100644
--- a/drivers/spi/omap_uwire.c
+++ b/drivers/spi/omap_uwire.c
@@ -339,8 +339,6 @@ static int uwire_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
         bits = spi->bits_per_word;
         if (t != NULL && t->bits_per_word)
                 bits = t->bits_per_word;
-        if (!bits)
-                bits = 8;
 
         if (bits > 16) {
                 pr_debug("%s: wordsize %d?\n", dev_name(&spi->dev), bits);
diff --git a/drivers/spi/orion_spi.c b/drivers/spi/orion_spi.c
index c8b0babdc2a6..6d5e33bb4b4a 100644
--- a/drivers/spi/orion_spi.c
+++ b/drivers/spi/orion_spi.c
@@ -369,9 +369,6 @@ static int orion_spi_setup(struct spi_device *spi)
                 orion_spi_setbits(orion_spi, ORION_SPI_IF_CONFIG_REG,
                                   (1 << 14));
 
-        if (spi->bits_per_word == 0)
-                spi->bits_per_word = 8;
-
         if ((spi->max_speed_hz == 0)
                         || (spi->max_speed_hz > orion_spi->max_speed))
                 spi->max_speed_hz = orion_spi->max_speed;
diff --git a/drivers/spi/pxa2xx_spi.c b/drivers/spi/pxa2xx_spi.c
index 3f3c08c6ba4e..c7365e0b22dd 100644
--- a/drivers/spi/pxa2xx_spi.c
+++ b/drivers/spi/pxa2xx_spi.c
@@ -1236,9 +1236,6 @@ static int setup(struct spi_device *spi)
         uint tx_thres = TX_THRESH_DFLT;
         uint rx_thres = RX_THRESH_DFLT;
 
-        if (!spi->bits_per_word)
-                spi->bits_per_word = 8;
-
         if (drv_data->ssp_type != PXA25x_SSP
                 && (spi->bits_per_word < 4 || spi->bits_per_word > 32)) {
                 dev_err(&spi->dev, "failed setup: ssp_type=%d, bits/wrd=%d "
@@ -1328,18 +1325,14 @@ static int setup(struct spi_device *spi)
 
         /* NOTE:  PXA25x_SSP _could_ use external clocking ... */
         if (drv_data->ssp_type != PXA25x_SSP)
-                dev_dbg(&spi->dev, "%d bits/word, %ld Hz, mode %d, %s\n",
-                                spi->bits_per_word,
+                dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
                                 clk_get_rate(ssp->clk)
                                         / (1 + ((chip->cr0 & SSCR0_SCR) >> 8)),
-                                spi->mode & 0x3,
                                 chip->enable_dma ? "DMA" : "PIO");
         else
-                dev_dbg(&spi->dev, "%d bits/word, %ld Hz, mode %d, %s\n",
-                                spi->bits_per_word,
+                dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
                                 clk_get_rate(ssp->clk) / 2
                                         / (1 + ((chip->cr0 & SSCR0_SCR) >> 8)),
-                                spi->mode & 0x3,
                                 chip->enable_dma ? "DMA" : "PIO");
 
         if (spi->bits_per_word <= 8) {
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 8eba98c8ed1e..0276bc37e255 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -265,7 +265,7 @@ int spi_add_device(struct spi_device *spi)
          * normally rely on the device being setup.  Devices
          * using SPI_CS_HIGH can't coexist well otherwise...
          */
-        status = spi->master->setup(spi);
+        status = spi_setup(spi);
         if (status < 0) {
                 dev_err(dev, "can't %s %s, status %d\n",
                                 "setup", dev_name(&spi->dev), status);
@@ -583,6 +583,59 @@ EXPORT_SYMBOL_GPL(spi_busnum_to_master);
 
 /*-------------------------------------------------------------------------*/
 
+/* Core methods for SPI master protocol drivers.  Some of the
+ * other core methods are currently defined as inline functions.
+ */
+
+/**
+ * spi_setup - setup SPI mode and clock rate
+ * @spi: the device whose settings are being modified
+ * Context: can sleep, and no requests are queued to the device
+ *
+ * SPI protocol drivers may need to update the transfer mode if the
+ * device doesn't work with its default.  They may likewise need
+ * to update clock rates or word sizes from initial values.  This function
+ * changes those settings, and must be called from a context that can sleep.
+ * Except for SPI_CS_HIGH, which takes effect immediately, the changes take
+ * effect the next time the device is selected and data is transferred to
+ * or from it.  When this function returns, the spi device is deselected.
+ *
+ * Note that this call will fail if the protocol driver specifies an option
+ * that the underlying controller or its driver does not support.  For
+ * example, not all hardware supports wire transfers using nine bit words,
+ * LSB-first wire encoding, or active-high chipselects.
+ */
+int spi_setup(struct spi_device *spi)
+{
+        int             status;
+
+        if (!spi->bits_per_word)
+                spi->bits_per_word = 8;
+
+        status = spi->master->setup(spi);
+
+        dev_dbg(&spi->dev, "setup mode %d, %s%s%s%s"
+                                "%u bits/w, %u Hz max --> %d\n",
+                        (int) (spi->mode & (SPI_CPOL | SPI_CPHA)),
+                        (spi->mode & SPI_CS_HIGH) ? "cs_high, " : "",
+                        (spi->mode & SPI_LSB_FIRST) ? "lsb, " : "",
+                        (spi->mode & SPI_3WIRE) ? "3wire, " : "",
+                        (spi->mode & SPI_LOOP) ? "loopback, " : "",
+                        spi->bits_per_word, spi->max_speed_hz,
+                        status);
+
+        return status;
+}
+EXPORT_SYMBOL_GPL(spi_setup);
+
+
+/*-------------------------------------------------------------------------*/
+
+/* Utility methods for SPI master protocol drivers, layered on
+ * top of the core.  Some other utility methods are defined as
+ * inline functions.
+ */
+
 static void spi_complete(void *arg)
 {
         complete(arg);
diff --git a/drivers/spi/spi_bfin5xx.c b/drivers/spi/spi_bfin5xx.c
index 2e5fd0977334..d54058a903be 100644
--- a/drivers/spi/spi_bfin5xx.c
+++ b/drivers/spi/spi_bfin5xx.c
@@ -1016,10 +1016,6 @@ static int bfin_spi_setup(struct spi_device *spi)
                 return -EINVAL;
         }
 
-        /* Zero (the default) here means 8 bits */
-        if (!spi->bits_per_word)
-                spi->bits_per_word = 8;
-
         if (spi->bits_per_word != 8 && spi->bits_per_word != 16)
                 return -EINVAL;
 
diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 85e61f451218..855b0b06e625 100644
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -201,9 +201,6 @@ int spi_bitbang_setup(struct spi_device *spi)
                 spi->controller_state = cs;
         }
 
-        if (!spi->bits_per_word)
-                spi->bits_per_word = 8;
-
         /* per-word shift register access, in hardware or bitbanging */
         cs->txrx_word = bitbang->txrx_word[spi->mode & (SPI_CPOL|SPI_CPHA)];
         if (!cs->txrx_word)
@@ -213,9 +210,7 @@ int spi_bitbang_setup(struct spi_device *spi)
         if (retval < 0)
                 return retval;
 
-        dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u nsec/bit\n",
-                        __func__, spi->mode & (SPI_CPOL | SPI_CPHA),
-                        spi->bits_per_word, 2 * cs->nsecs);
+        dev_dbg(&spi->dev, "%s, %u nsec/bit\n", __func__, 2 * cs->nsecs);
 
         /* NOTE we _need_ to call chipselect() early, ideally with adapter
          * setup, unless the hardware defaults cooperate to avoid confusion
diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c
index 0671aeef5792..26d5ef06dbd9 100644
--- a/drivers/spi/spi_imx.c
+++ b/drivers/spi/spi_imx.c
@@ -1286,10 +1286,7 @@ static int setup(struct spi_device *spi)
 
         /* SPI word width */
         tmp = spi->bits_per_word;
-        if (tmp == 0) {
-                tmp = 8;
-                spi->bits_per_word = 8;
-        } else if (tmp > 16) {
+        if (tmp > 16) {
                 status = -EINVAL;
                 dev_err(&spi->dev,
                         "setup - "
diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index a32ccb44065e..0926a3e293e0 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -447,9 +447,6 @@ static int mpc83xx_spi_setup(struct spi_device *spi)
         }
         mpc83xx_spi = spi_master_get_devdata(spi->master);
 
-        if (!spi->bits_per_word)
-                spi->bits_per_word = 8;
-
         hw_mode = cs->hw_mode; /* Save orginal settings */
         cs->hw_mode = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
         /* mask out bits we are going to set */
@@ -471,9 +468,6 @@ static int mpc83xx_spi_setup(struct spi_device *spi)
                 return retval;
         }
 
-        dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u Hz\n",
-                __func__, spi->mode & (SPI_CPOL | SPI_CPHA),
-                spi->bits_per_word, spi->max_speed_hz);
 #if 0 /* Don't think this is needed */
         /* NOTE we _need_ to call chipselect() early, ideally with adapter
          * setup, unless the hardware defaults cooperate to avoid confusion
diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c
index b3ebc1d0f85f..18a4c7f54380 100644
--- a/drivers/spi/spi_s3c24xx.c
+++ b/drivers/spi/spi_s3c24xx.c
@@ -153,9 +153,6 @@ static int s3c24xx_spi_setup(struct spi_device *spi)
 {
         int ret;
 
-        if (!spi->bits_per_word)
-                spi->bits_per_word = 8;
-
         if (spi->mode & ~MODEBITS) {
                 dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
                         spi->mode & ~MODEBITS);
@@ -168,10 +165,6 @@ static int s3c24xx_spi_setup(struct spi_device *spi)
                 return ret;
         }
 
-        dev_dbg(&spi->dev, "%s: mode %d, %u bpw, %d hz\n",
-                __func__, spi->mode, spi->bits_per_word,
-                spi->max_speed_hz);
-
         return 0;
 }
 
diff --git a/drivers/spi/spi_txx9.c b/drivers/spi/spi_txx9.c
index 29cbb065618a..8e36b2153d9a 100644
--- a/drivers/spi/spi_txx9.c
+++ b/drivers/spi/spi_txx9.c
@@ -126,7 +126,7 @@ static int txx9spi_setup(struct spi_device *spi)
                         || spi->max_speed_hz < c->min_speed_hz)
                 return -EINVAL;
 
-        bits_per_word = spi->bits_per_word ? : 8;
+        bits_per_word = spi->bits_per_word;
         if (bits_per_word != 8 && bits_per_word != 16)
                 return -EINVAL;
 
diff --git a/drivers/spi/xilinx_spi.c b/drivers/spi/xilinx_spi.c
index 494d3f756e29..2d7e6b81fb4a 100644
--- a/drivers/spi/xilinx_spi.c
+++ b/drivers/spi/xilinx_spi.c
@@ -170,9 +170,6 @@ static int xilinx_spi_setup(struct spi_device *spi)
         xspi = spi_master_get_devdata(spi->master);
         bitbang = &xspi->bitbang;
 
-        if (!spi->bits_per_word)
-                spi->bits_per_word = 8;
-
         if (spi->mode & ~MODEBITS) {
                 dev_err(&spi->dev, "%s, unsupported mode bits %x\n",
                         __func__, spi->mode & ~MODEBITS);
@@ -183,9 +180,6 @@ static int xilinx_spi_setup(struct spi_device *spi)
         if (retval < 0)
                 return retval;
 
-        dev_dbg(&spi->dev, "%s, mode %d, %u bits/w, %u nsec/bit\n",
-                __func__, spi->mode & MODEBITS, spi->bits_per_word, 0);
-
         return 0;
 }