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-rw-r--r--Documentation/spi/00-INDEX22
-rw-r--r--Documentation/spi/spi-summary17
-rw-r--r--Documentation/spi/spidev6
-rw-r--r--Documentation/spi/spidev_fdx.c8
-rw-r--r--Documentation/spi/spidev_test.c45
5 files changed, 87 insertions, 11 deletions
diff --git a/Documentation/spi/00-INDEX b/Documentation/spi/00-INDEX
new file mode 100644
index 0000000..a128fa8
--- /dev/null
+++ b/Documentation/spi/00-INDEX
@@ -0,0 +1,22 @@
+00-INDEX
+ - this file.
+Makefile
+ - Makefile for the example sourcefiles.
+butterfly
+ - AVR Butterfly SPI driver overview and pin configuration.
+ep93xx_spi
+ - Basic EP93xx SPI driver configuration.
+pxa2xx
+ - PXA2xx SPI master controller build by spi_message fifo wq
+spidev
+ - Intro to the userspace API for spi devices
+spidev_fdx.c
+ - spidev example file
+spi-lm70llp
+ - Connecting an LM70-LLP sensor to the kernel via the SPI subsys.
+spi-sc18is602
+ - NXP SC18IS602/603 I2C-bus to SPI bridge
+spi-summary
+ - (Linux) SPI overview. If unsure about SPI or SPI in Linux, start here.
+spidev_test.c
+ - SPI testing utility.
diff --git a/Documentation/spi/spi-summary b/Documentation/spi/spi-summary
index f72e0d1..7982bcc 100644
--- a/Documentation/spi/spi-summary
+++ b/Documentation/spi/spi-summary
@@ -543,7 +543,22 @@ SPI MASTER METHODS
queuing transfers that arrive in the meantime. When the driver is
finished with this message, it must call
spi_finalize_current_message() so the subsystem can issue the next
- transfer. This may sleep.
+ message. This may sleep.
+
+ master->transfer_one(struct spi_master *master, struct spi_device *spi,
+ struct spi_transfer *transfer)
+ The subsystem calls the driver to transfer a single transfer while
+ queuing transfers that arrive in the meantime. When the driver is
+ finished with this transfer, it must call
+ spi_finalize_current_transfer() so the subsystem can issue the next
+ transfer. This may sleep. Note: transfer_one and transfer_one_message
+ are mutually exclusive; when both are set, the generic subsystem does
+ not call your transfer_one callback.
+
+ Return values:
+ negative errno: error
+ 0: transfer is finished
+ 1: transfer is still in progress
DEPRECATED METHODS
diff --git a/Documentation/spi/spidev b/Documentation/spi/spidev
index ed2da5e..3d14035 100644
--- a/Documentation/spi/spidev
+++ b/Documentation/spi/spidev
@@ -85,6 +85,12 @@ settings for data transfer parameters:
SPI_MODE_0..SPI_MODE_3; or if you prefer you can combine SPI_CPOL
(clock polarity, idle high iff this is set) or SPI_CPHA (clock phase,
sample on trailing edge iff this is set) flags.
+ Note that this request is limited to SPI mode flags that fit in a
+ single byte.
+
+ SPI_IOC_RD_MODE32, SPI_IOC_WR_MODE32 ... pass a pointer to a uin32_t
+ which will return (RD) or assign (WR) the full SPI transfer mode,
+ not limited to the bits that fit in one byte.
SPI_IOC_RD_LSB_FIRST, SPI_IOC_WR_LSB_FIRST ... pass a pointer to a byte
which will return (RD) or assign (WR) the bit justification used to
diff --git a/Documentation/spi/spidev_fdx.c b/Documentation/spi/spidev_fdx.c
index 36ec077..0ea3e51 100644
--- a/Documentation/spi/spidev_fdx.c
+++ b/Documentation/spi/spidev_fdx.c
@@ -78,10 +78,10 @@ static void do_msg(int fd, int len)
static void dumpstat(const char *name, int fd)
{
- __u8 mode, lsb, bits;
- __u32 speed;
+ __u8 lsb, bits;
+ __u32 mode, speed;
- if (ioctl(fd, SPI_IOC_RD_MODE, &mode) < 0) {
+ if (ioctl(fd, SPI_IOC_RD_MODE32, &mode) < 0) {
perror("SPI rd_mode");
return;
}
@@ -98,7 +98,7 @@ static void dumpstat(const char *name, int fd)
return;
}
- printf("%s: spi mode %d, %d bits %sper word, %d Hz max\n",
+ printf("%s: spi mode 0x%x, %d bits %sper word, %d Hz max\n",
name, mode, bits, lsb ? "(lsb first) " : "", speed);
}
diff --git a/Documentation/spi/spidev_test.c b/Documentation/spi/spidev_test.c
index 16feda9..3a2f9d5 100644
--- a/Documentation/spi/spidev_test.c
+++ b/Documentation/spi/spidev_test.c
@@ -30,7 +30,7 @@ static void pabort(const char *s)
}
static const char *device = "/dev/spidev1.1";
-static uint8_t mode;
+static uint32_t mode;
static uint8_t bits = 8;
static uint32_t speed = 500000;
static uint16_t delay;
@@ -57,6 +57,21 @@ static void transfer(int fd)
.bits_per_word = bits,
};
+ if (mode & SPI_TX_QUAD)
+ tr.tx_nbits = 4;
+ else if (mode & SPI_TX_DUAL)
+ tr.tx_nbits = 2;
+ if (mode & SPI_RX_QUAD)
+ tr.rx_nbits = 4;
+ else if (mode & SPI_RX_DUAL)
+ tr.rx_nbits = 2;
+ if (!(mode & SPI_LOOP)) {
+ if (mode & (SPI_TX_QUAD | SPI_TX_DUAL))
+ tr.rx_buf = 0;
+ else if (mode & (SPI_RX_QUAD | SPI_RX_DUAL))
+ tr.tx_buf = 0;
+ }
+
ret = ioctl(fd, SPI_IOC_MESSAGE(1), &tr);
if (ret < 1)
pabort("can't send spi message");
@@ -81,7 +96,11 @@ static void print_usage(const char *prog)
" -O --cpol clock polarity\n"
" -L --lsb least significant bit first\n"
" -C --cs-high chip select active high\n"
- " -3 --3wire SI/SO signals shared\n");
+ " -3 --3wire SI/SO signals shared\n"
+ " -N --no-cs no chip select\n"
+ " -R --ready slave pulls low to pause\n"
+ " -2 --dual dual transfer\n"
+ " -4 --quad quad transfer\n");
exit(1);
}
@@ -101,11 +120,13 @@ static void parse_opts(int argc, char *argv[])
{ "3wire", 0, 0, '3' },
{ "no-cs", 0, 0, 'N' },
{ "ready", 0, 0, 'R' },
+ { "dual", 0, 0, '2' },
+ { "quad", 0, 0, '4' },
{ NULL, 0, 0, 0 },
};
int c;
- c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR", lopts, NULL);
+ c = getopt_long(argc, argv, "D:s:d:b:lHOLC3NR24", lopts, NULL);
if (c == -1)
break;
@@ -147,11 +168,23 @@ static void parse_opts(int argc, char *argv[])
case 'R':
mode |= SPI_READY;
break;
+ case '2':
+ mode |= SPI_TX_DUAL;
+ break;
+ case '4':
+ mode |= SPI_TX_QUAD;
+ break;
default:
print_usage(argv[0]);
break;
}
}
+ if (mode & SPI_LOOP) {
+ if (mode & SPI_TX_DUAL)
+ mode |= SPI_RX_DUAL;
+ if (mode & SPI_TX_QUAD)
+ mode |= SPI_RX_QUAD;
+ }
}
int main(int argc, char *argv[])
@@ -168,11 +201,11 @@ int main(int argc, char *argv[])
/*
* spi mode
*/
- ret = ioctl(fd, SPI_IOC_WR_MODE, &mode);
+ ret = ioctl(fd, SPI_IOC_WR_MODE32, &mode);
if (ret == -1)
pabort("can't set spi mode");
- ret = ioctl(fd, SPI_IOC_RD_MODE, &mode);
+ ret = ioctl(fd, SPI_IOC_RD_MODE32, &mode);
if (ret == -1)
pabort("can't get spi mode");
@@ -198,7 +231,7 @@ int main(int argc, char *argv[])
if (ret == -1)
pabort("can't get max speed hz");
- printf("spi mode: %d\n", mode);
+ printf("spi mode: 0x%x\n", mode);
printf("bits per word: %d\n", bits);
printf("max speed: %d Hz (%d KHz)\n", speed, speed/1000);
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