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authorLinus Torvalds <torvalds@linux-foundation.org>2010-05-25 12:04:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-25 12:04:17 -0700
commit702c0b04978ce316ec05f4d0a9c148fac124335b (patch)
tree3908c5821221d950a6b1a7e2e898899e63e7d437 /Documentation
parentc19eb8f0d1bd442ed1aff0b413dd822620771c29 (diff)
parentbf6a67ee3427ab142136e03e90d0b67ecbca5ff2 (diff)
Merge branch 'next-spi' of git://git.secretlab.ca/git/linux-2.6
* 'next-spi' of git://git.secretlab.ca/git/linux-2.6: spi/xilinx: Fix compile error spi/davinci: Fix clock prescale factor computation spi: move bitbang txrx utility functions to private header spi/mpc5121: Add SPI master driver for MPC5121 PSC powerpc/mpc5121: move PSC FIFO memory init to platform code spi/ep93xx: implemented driver for Cirrus EP93xx SPI controller Documentation/spi/* compile warning fix spi/omap2_mcspi: Check params before dereference or use spi/omap2_mcspi: add turbo mode support spi/omap2_mcspi: change default DMA_MIN_BYTES value to 160 spi/pl022: fix stop queue procedure spi/pl022: add support for the PL023 derivate spi/pl022: fix up differences between ARM and ST versions spi/spi_mpc8xxx: Do not use map_tx_dma to unmap rx_dma spi/spi_mpc8xxx: Fix QE mode Litte Endian spi/spi_mpc8xxx: fix potential memory corruption.
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/spi/ep93xx_spi95
-rw-r--r--Documentation/spi/spidev_fdx.c4
2 files changed, 97 insertions, 2 deletions
diff --git a/Documentation/spi/ep93xx_spi b/Documentation/spi/ep93xx_spi
new file mode 100644
index 00000000000..6325f5b4863
--- /dev/null
+++ b/Documentation/spi/ep93xx_spi
@@ -0,0 +1,95 @@
+Cirrus EP93xx SPI controller driver HOWTO
+=========================================
+
+ep93xx_spi driver brings SPI master support for EP93xx SPI controller. Chip
+selects are implemented with GPIO lines.
+
+NOTE: If possible, don't use SFRMOUT (SFRM1) signal as a chip select. It will
+not work correctly (it cannot be controlled by software). Use GPIO lines
+instead.
+
+Sample configuration
+====================
+
+Typically driver configuration is done in platform board files (the files under
+arch/arm/mach-ep93xx/*.c). In this example we configure MMC over SPI through
+this driver on TS-7260 board. You can adapt the code to suit your needs.
+
+This example uses EGPIO9 as SD/MMC card chip select (this is wired in DIO1
+header on the board).
+
+You need to select CONFIG_MMC_SPI to use mmc_spi driver.
+
+arch/arm/mach-ep93xx/ts72xx.c:
+
+...
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+
+#include <mach/ep93xx_spi.h>
+
+/* this is our GPIO line used for chip select */
+#define MMC_CHIP_SELECT_GPIO EP93XX_GPIO_LINE_EGPIO9
+
+static int ts72xx_mmc_spi_setup(struct spi_device *spi)
+{
+ int err;
+
+ err = gpio_request(MMC_CHIP_SELECT_GPIO, spi->modalias);
+ if (err)
+ return err;
+
+ gpio_direction_output(MMC_CHIP_SELECT_GPIO, 1);
+
+ return 0;
+}
+
+static void ts72xx_mmc_spi_cleanup(struct spi_device *spi)
+{
+ gpio_set_value(MMC_CHIP_SELECT_GPIO, 1);
+ gpio_direction_input(MMC_CHIP_SELECT_GPIO);
+ gpio_free(MMC_CHIP_SELECT_GPIO);
+}
+
+static void ts72xx_mmc_spi_cs_control(struct spi_device *spi, int value)
+{
+ gpio_set_value(MMC_CHIP_SELECT_GPIO, value);
+}
+
+static struct ep93xx_spi_chip_ops ts72xx_mmc_spi_ops = {
+ .setup = ts72xx_mmc_spi_setup,
+ .cleanup = ts72xx_mmc_spi_cleanup,
+ .cs_control = ts72xx_mmc_spi_cs_control,
+};
+
+static struct spi_board_info ts72xx_spi_devices[] __initdata = {
+ {
+ .modalias = "mmc_spi",
+ .controller_data = &ts72xx_mmc_spi_ops,
+ /*
+ * We use 10 MHz even though the maximum is 7.4 MHz. The driver
+ * will limit it automatically to max. frequency.
+ */
+ .max_speed_hz = 10 * 1000 * 1000,
+ .bus_num = 0,
+ .chip_select = 0,
+ .mode = SPI_MODE_0,
+ },
+};
+
+static struct ep93xx_spi_info ts72xx_spi_info = {
+ .num_chipselect = ARRAY_SIZE(ts72xx_spi_devices),
+};
+
+static void __init ts72xx_init_machine(void)
+{
+ ...
+ ep93xx_register_spi(&ts72xx_spi_info, ts72xx_spi_devices,
+ ARRAY_SIZE(ts72xx_spi_devices));
+}
+
+Thanks to
+=========
+Martin Guy, H. Hartley Sweeten and others who helped me during development of
+the driver. Simplemachines.it donated me a Sim.One board which I used testing
+the driver on EP9307.
diff --git a/Documentation/spi/spidev_fdx.c b/Documentation/spi/spidev_fdx.c
index fc354f76038..36ec0774ca0 100644
--- a/Documentation/spi/spidev_fdx.c
+++ b/Documentation/spi/spidev_fdx.c
@@ -58,10 +58,10 @@ static void do_msg(int fd, int len)
len = sizeof buf;
buf[0] = 0xaa;
- xfer[0].tx_buf = (__u64) buf;
+ xfer[0].tx_buf = (unsigned long)buf;
xfer[0].len = 1;
- xfer[1].rx_buf = (__u64) buf;
+ xfer[1].rx_buf = (unsigned long) buf;
xfer[1].len = len;
status = ioctl(fd, SPI_IOC_MESSAGE(2), xfer);