SPI controller drivers: check for unsupported modes

Minor SPI controller driver updates: make the setup() methods reject
spi->mode bits they don't support, by masking aginst the inverse of bits
they *do* support.  This insures against misbehavior later when new mode
bits get added.

Most controllers can't support SPI_LSB_FIRST; more handle SPI_CS_HIGH.
Support for all four SPI clock/transfer modes is routine.

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>

diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c
index 8b2601de36306e085d9a55481b0b777248db4946..7524a84bdd504212d03511a88e3284ed2f890ed6 100644 (file)
--- a/drivers/spi/atmel_spi.c
+++ b/drivers/spi/atmel_spi.c
@@ -350,6 +350,7 @@ atmel_spi_interrupt(int irq, void *dev_id)
        return ret;
 }
 
+/* the spi->mode bits understood by this driver: */
 #define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
 
 static int atmel_spi_setup(struct spi_device *spi)

diff --git a/drivers/spi/au1550_spi.c b/drivers/spi/au1550_spi.c
index ae2b1af0dba48a6f7975fcfcdec95b62e63090e2..c47a650183a14beeec627db2f439d47b7a08c401 100644 (file)
--- a/drivers/spi/au1550_spi.c
+++ b/drivers/spi/au1550_spi.c
@@ -280,6 +280,9 @@ static int au1550_spi_setupxfer(struct spi_device *spi, struct spi_transfer *t)
        return 0;
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST)
+
 static int au1550_spi_setup(struct spi_device *spi)
 {
        struct au1550_spi *hw = spi_master_get_devdata(spi->master);
@@ -292,6 +295,12 @@ static int au1550_spi_setup(struct spi_device *spi)
                return -EINVAL;
        }
 
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
+               return -EINVAL;
+       }
+
        if (spi->max_speed_hz == 0)
                spi->max_speed_hz = hw->freq_max;
        if (spi->max_speed_hz > hw->freq_max

diff --git a/drivers/spi/mpc52xx_psc_spi.c b/drivers/spi/mpc52xx_psc_spi.c
index 11f36bef3057493a6c7b0c3e79e5f270f220a601..d2a4b2bdb07b6cbae5f2a4b4d51727a813ed2596 100644 (file)
--- a/drivers/spi/mpc52xx_psc_spi.c
+++ b/drivers/spi/mpc52xx_psc_spi.c
@@ -270,6 +270,9 @@ static void mpc52xx_psc_spi_work(struct work_struct *work)
        spin_unlock_irq(&mps->lock);
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST)
+
 static int mpc52xx_psc_spi_setup(struct spi_device *spi)
 {
        struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
@@ -279,6 +282,12 @@ static int mpc52xx_psc_spi_setup(struct spi_device *spi)
        if (spi->bits_per_word%8)
                return -EINVAL;
 
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
+               return -EINVAL;
+       }
+
        if (!cs) {
                cs = kzalloc(sizeof *cs, GFP_KERNEL);
                if (!cs)

diff --git a/drivers/spi/omap_uwire.c b/drivers/spi/omap_uwire.c
index 95183e1df525c6a1a14ac6244d0f94f5fc3d05ea..d275c615a73ecb7a516689595c9c9c8dca322062 100644 (file)
--- a/drivers/spi/omap_uwire.c
+++ b/drivers/spi/omap_uwire.c
@@ -445,10 +445,19 @@ done:
        return status;
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
+
 static int uwire_setup(struct spi_device *spi)
 {
        struct uwire_state *ust = spi->controller_state;
 
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
+               return -EINVAL;
+       }
+
        if (ust == NULL) {
                ust = kzalloc(sizeof(*ust), GFP_KERNEL);
                if (ust == NULL)

diff --git a/drivers/spi/pxa2xx_spi.c b/drivers/spi/pxa2xx_spi.c
index 9f2c887ffa0466cf8d30105ed1ee6d5860fa29f4..e51311b2da0b05855d45f4beb076dda923610859 100644 (file)
--- a/drivers/spi/pxa2xx_spi.c
+++ b/drivers/spi/pxa2xx_spi.c
@@ -1067,6 +1067,9 @@ static int transfer(struct spi_device *spi, struct spi_message *msg)
        return 0;
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA)
+
 static int setup(struct spi_device *spi)
 {
        struct pxa2xx_spi_chip *chip_info = NULL;
@@ -1093,6 +1096,12 @@ static int setup(struct spi_device *spi)
                return -EINVAL;
        }
 
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
+               return -EINVAL;
+       }
+
        /* Only alloc on first setup */
        chip = spi_get_ctldata(spi);
        if (!chip) {

diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 88425e1af4d353fcc0ce14c0dd29c130c770f7f1..0c85c984ccb4fd53e5b243fbe1cd5d38d877d563 100644 (file)
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -187,12 +187,10 @@ int spi_bitbang_setup(struct spi_device *spi)
 
        bitbang = spi_master_get_devdata(spi->master);
 
-       /* REVISIT: some systems will want to support devices using lsb-first
-        * bit encodings on the wire.  In pure software that would be trivial,
-        * just bitbang_txrx_le_cphaX() routines shifting the other way, and
-        * some hardware controllers also have this support.
+       /* Bitbangers can support SPI_CS_HIGH, SPI_3WIRE, and so on;
+        * add those to master->flags, and provide the other support.
         */
-       if ((spi->mode & SPI_LSB_FIRST) != 0)
+       if ((spi->mode & ~(SPI_CPOL|SPI_CPHA|bitbang->flags)) != 0)
                return -EINVAL;
 
        if (!cs) {

diff --git a/drivers/spi/spi_imx.c b/drivers/spi/spi_imx.c
index 656be4a5094a68cfd1d6d10b5fb936e2dbf7a1e0..aee9ad6f633ca14e2619c78e0d36dd82df4ba34f 100644 (file)
--- a/drivers/spi/spi_imx.c
+++ b/drivers/spi/spi_imx.c
@@ -1163,6 +1163,9 @@ msg_rejected:
        return -EINVAL;
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
+
 /* On first setup bad values must free chip_data memory since will cause
    spi_new_device to fail. Bad value setup from protocol driver are simply not
    applied and notified to the calling driver. */
@@ -1174,6 +1177,12 @@ static int setup(struct spi_device *spi)
        u32 tmp;
        int status = 0;
 
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
+               return -EINVAL;
+       }
+
        /* Get controller data */
        chip_info = spi->controller_data;
 
@@ -1245,21 +1254,6 @@ static int setup(struct spi_device *spi)
 
        /* SPI mode */
        tmp = spi->mode;
-       if (tmp & SPI_LSB_FIRST) {
-               status = -EINVAL;
-               if (first_setup) {
-                       dev_err(&spi->dev,
-                               "setup - "
-                               "HW doesn't support LSB first transfer\n");
-                       goto err_first_setup;
-               } else {
-                       dev_err(&spi->dev,
-                               "setup - "
-                               "HW doesn't support LSB first transfer, "
-                               "default to MSB first\n");
-                       spi->mode &= ~SPI_LSB_FIRST;
-               }
-       }
        if (tmp & SPI_CS_HIGH) {
                u32_EDIT(chip->control,
                                SPI_CONTROL_SSPOL, SPI_CONTROL_SSPOL_ACT_HIGH);

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index e9798bf7b8c6a0dff43795edc1ec1ee36ade6c42..9cdbc12278e51ca55b4121920a675554da692dcb 100644 (file)
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -232,12 +232,21 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
        return 0;
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
+
 static int mpc83xx_spi_setup(struct spi_device *spi)
 {
        struct spi_bitbang *bitbang;
        struct mpc83xx_spi *mpc83xx_spi;
        int retval;
 
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
+               return -EINVAL;
+       }
+
        if (!spi->max_speed_hz)
                return -EINVAL;
 

diff --git a/drivers/spi/spi_s3c24xx.c b/drivers/spi/spi_s3c24xx.c
index d5a710f6e445cf3aa0bf64e1fb1c6f5f827f50eb..7071ff8da63e47328fc55bab105a3e11ca27932d 100644 (file)
--- a/drivers/spi/spi_s3c24xx.c
+++ b/drivers/spi/spi_s3c24xx.c
@@ -146,6 +146,9 @@ static int s3c24xx_spi_setupxfer(struct spi_device *spi,
        return 0;
 }
 
+/* the spi->mode bits understood by this driver: */
+#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
+
 static int s3c24xx_spi_setup(struct spi_device *spi)
 {
        int ret;
@@ -153,8 +156,11 @@ static int s3c24xx_spi_setup(struct spi_device *spi)
        if (!spi->bits_per_word)
                spi->bits_per_word = 8;
 
-       if ((spi->mode & SPI_LSB_FIRST) != 0)
+       if (spi->mode & ~MODEBITS) {
+               dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n",
+                       spi->mode & ~MODEBITS);
                return -EINVAL;
+       }
 
        ret = s3c24xx_spi_setupxfer(spi, NULL);
        if (ret < 0) {

diff --git a/include/linux/spi/spi_bitbang.h b/include/linux/spi/spi_bitbang.h
index 9dbca629dcfbfb2f401965e9a4ff87ddda38ce2c..b8db32cea1de535c4762abd9feabc82db8384381 100644 (file)
--- a/include/linux/spi/spi_bitbang.h
+++ b/include/linux/spi/spi_bitbang.h
@@ -26,6 +26,7 @@ struct spi_bitbang {
        struct list_head        queue;
        u8                      busy;
        u8                      use_dma;
+       u8                      flags;          /* extra spi->mode support */
 
        struct spi_master       *master;