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author | H. Nikolaus Schaller <hns@goldelico.com> | 2012-03-26 20:55:28 +0200 |
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committer | H. Nikolaus Schaller <hns@goldelico.com> | 2012-03-26 20:55:28 +0200 |
commit | 92988a21ad4c4c9504295ccb580c9f806134471b (patch) | |
tree | 5effc9f14170112450de05c67dafbe8d5034d595 /include/spi.h | |
parent | ca2b506783b676c95762c54ea24dcfdaae1947c9 (diff) | |
download | bootable_bootloader_goldelico_gta04-92988a21ad4c4c9504295ccb580c9f806134471b.zip bootable_bootloader_goldelico_gta04-92988a21ad4c4c9504295ccb580c9f806134471b.tar.gz bootable_bootloader_goldelico_gta04-92988a21ad4c4c9504295ccb580c9f806134471b.tar.bz2 |
added boot script files to repository
Diffstat (limited to 'include/spi.h')
-rw-r--r-- | include/spi.h | 200 |
1 files changed, 0 insertions, 200 deletions
diff --git a/include/spi.h b/include/spi.h deleted file mode 100644 index 320e50e..0000000 --- a/include/spi.h +++ /dev/null @@ -1,200 +0,0 @@ -/* - * (C) Copyright 2001 - * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com. - * - * See file CREDITS for list of people who contributed to this - * project. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of - * the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, - * MA 02111-1307 USA - */ - -#ifndef _SPI_H_ -#define _SPI_H_ - -/* Controller-specific definitions: */ - -/* CONFIG_HARD_SPI triggers SPI bus initialization in PowerPC */ -#ifdef CONFIG_MPC8XXX_SPI -# ifndef CONFIG_HARD_SPI -# define CONFIG_HARD_SPI -# endif -#endif - -/* SPI mode flags */ -#define SPI_CPHA 0x01 /* clock phase */ -#define SPI_CPOL 0x02 /* clock polarity */ -#define SPI_MODE_0 (0|0) /* (original MicroWire) */ -#define SPI_MODE_1 (0|SPI_CPHA) -#define SPI_MODE_2 (SPI_CPOL|0) -#define SPI_MODE_3 (SPI_CPOL|SPI_CPHA) -#define SPI_CS_HIGH 0x04 /* CS active high */ -#define SPI_LSB_FIRST 0x08 /* per-word bits-on-wire */ -#define SPI_3WIRE 0x10 /* SI/SO signals shared */ -#define SPI_LOOP 0x20 /* loopback mode */ - -/* SPI transfer flags */ -#define SPI_XFER_BEGIN 0x01 /* Assert CS before transfer */ -#define SPI_XFER_END 0x02 /* Deassert CS after transfer */ - -/*----------------------------------------------------------------------- - * Representation of a SPI slave, i.e. what we're communicating with. - * - * Drivers are expected to extend this with controller-specific data. - * - * bus: ID of the bus that the slave is attached to. - * cs: ID of the chip select connected to the slave. - */ -struct spi_slave { - unsigned int bus; - unsigned int cs; -}; - -/*----------------------------------------------------------------------- - * Initialization, must be called once on start up. - * - * TODO: I don't think we really need this. - */ -void spi_init(void); - -/*----------------------------------------------------------------------- - * Set up communications parameters for a SPI slave. - * - * This must be called once for each slave. Note that this function - * usually doesn't touch any actual hardware, it only initializes the - * contents of spi_slave so that the hardware can be easily - * initialized later. - * - * bus: Bus ID of the slave chip. - * cs: Chip select ID of the slave chip on the specified bus. - * max_hz: Maximum SCK rate in Hz. - * mode: Clock polarity, clock phase and other parameters. - * - * Returns: A spi_slave reference that can be used in subsequent SPI - * calls, or NULL if one or more of the parameters are not supported. - */ -struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs, - unsigned int max_hz, unsigned int mode); - -/*----------------------------------------------------------------------- - * Free any memory associated with a SPI slave. - * - * slave: The SPI slave - */ -void spi_free_slave(struct spi_slave *slave); - -/*----------------------------------------------------------------------- - * Claim the bus and prepare it for communication with a given slave. - * - * This must be called before doing any transfers with a SPI slave. It - * will enable and initialize any SPI hardware as necessary, and make - * sure that the SCK line is in the correct idle state. It is not - * allowed to claim the same bus for several slaves without releasing - * the bus in between. - * - * slave: The SPI slave - * - * Returns: 0 if the bus was claimed successfully, or a negative value - * if it wasn't. - */ -int spi_claim_bus(struct spi_slave *slave); - -/*----------------------------------------------------------------------- - * Release the SPI bus - * - * This must be called once for every call to spi_claim_bus() after - * all transfers have finished. It may disable any SPI hardware as - * appropriate. - * - * slave: The SPI slave - */ -void spi_release_bus(struct spi_slave *slave); - -/*----------------------------------------------------------------------- - * SPI transfer - * - * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks - * "bitlen" bits in the SPI MISO port. That's just the way SPI works. - * - * The source of the outgoing bits is the "dout" parameter and the - * destination of the input bits is the "din" parameter. Note that "dout" - * and "din" can point to the same memory location, in which case the - * input data overwrites the output data (since both are buffered by - * temporary variables, this is OK). - * - * spi_xfer() interface: - * slave: The SPI slave which will be sending/receiving the data. - * bitlen: How many bits to write and read. - * dout: Pointer to a string of bits to send out. The bits are - * held in a byte array and are sent MSB first. - * din: Pointer to a string of bits that will be filled in. - * flags: A bitwise combination of SPI_XFER_* flags. - * - * Returns: 0 on success, not 0 on failure - */ -int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout, - void *din, unsigned long flags); - -/*----------------------------------------------------------------------- - * Determine if a SPI chipselect is valid. - * This function is provided by the board if the low-level SPI driver - * needs it to determine if a given chipselect is actually valid. - * - * Returns: 1 if bus:cs identifies a valid chip on this board, 0 - * otherwise. - */ -int spi_cs_is_valid(unsigned int bus, unsigned int cs); - -/*----------------------------------------------------------------------- - * Activate a SPI chipselect. - * This function is provided by the board code when using a driver - * that can't control its chipselects automatically (e.g. - * common/soft_spi.c). When called, it should activate the chip select - * to the device identified by "slave". - */ -void spi_cs_activate(struct spi_slave *slave); - -/*----------------------------------------------------------------------- - * Deactivate a SPI chipselect. - * This function is provided by the board code when using a driver - * that can't control its chipselects automatically (e.g. - * common/soft_spi.c). When called, it should deactivate the chip - * select to the device identified by "slave". - */ -void spi_cs_deactivate(struct spi_slave *slave); - -/*----------------------------------------------------------------------- - * Write 8 bits, then read 8 bits. - * slave: The SPI slave we're communicating with - * byte: Byte to be written - * - * Returns: The value that was read, or a negative value on error. - * - * TODO: This function probably shouldn't be inlined. - */ -static inline int spi_w8r8(struct spi_slave *slave, unsigned char byte) -{ - unsigned char dout[2]; - unsigned char din[2]; - int ret; - - dout[0] = byte; - dout[1] = 0; - - ret = spi_xfer(slave, 16, dout, din, SPI_XFER_BEGIN | SPI_XFER_END); - return ret < 0 ? ret : din[1]; -} - -#endif /* _SPI_H_ */ |