linux/arch/arm/mach-u300/spi.c
Kevin Wells bde435a9ca spi/pl022: Add spi->mode support to AMBA SPI driver
This patch adds spi->mode support for the AMBA pl022 driver and
allows spidev to correctly alter SPI modes. Unused fields used in
the pl022 header file for the pl022_config_chip have been removed.

The ab8500 client driver selects the data transfer size instead
of the platform data.

For platforms that use the amba pl022 driver, the unused fields
in the controller data structure have been removed and the .mode
field in the SPI board info structure is used instead.

Signed-off-by: Kevin Wells <wellsk40@gmail.com>
Tested-by: Linus Walleij <linus.walleij@stericsson.com>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-10-12 21:37:37 -06:00

116 lines
3.2 KiB
C

/*
* arch/arm/mach-u300/spi.c
*
* Copyright (C) 2009 ST-Ericsson AB
* License terms: GNU General Public License (GPL) version 2
*
* Author: Linus Walleij <linus.walleij@stericsson.com>
*/
#include <linux/device.h>
#include <linux/amba/bus.h>
#include <linux/spi/spi.h>
#include <linux/amba/pl022.h>
#include <linux/err.h>
#include "padmux.h"
/*
* The following is for the actual devices on the SSP/SPI bus
*/
#ifdef CONFIG_MACH_U300_SPIDUMMY
static void select_dummy_chip(u32 chipselect)
{
pr_debug("CORE: %s called with CS=0x%x (%s)\n",
__func__,
chipselect,
chipselect ? "unselect chip" : "select chip");
/*
* Here you would write the chip select value to the GPIO pins if
* this was a real chip (but this is a loopback dummy).
*/
}
struct pl022_config_chip dummy_chip_info = {
/*
* available POLLING_TRANSFER and INTERRUPT_TRANSFER,
* DMA_TRANSFER does not work
*/
.com_mode = INTERRUPT_TRANSFER,
.iface = SSP_INTERFACE_MOTOROLA_SPI,
/* We can only act as master but SSP_SLAVE is possible in theory */
.hierarchy = SSP_MASTER,
/* 0 = drive TX even as slave, 1 = do not drive TX as slave */
.slave_tx_disable = 0,
.rx_lev_trig = SSP_RX_1_OR_MORE_ELEM,
.tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC,
.ctrl_len = SSP_BITS_12,
.wait_state = SSP_MWIRE_WAIT_ZERO,
.duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX,
/*
* This is where you insert a call to a function to enable CS
* (usually GPIO) for a certain chip.
*/
.cs_control = select_dummy_chip,
};
#endif
static struct spi_board_info u300_spi_devices[] = {
#ifdef CONFIG_MACH_U300_SPIDUMMY
{
/* A dummy chip used for loopback tests */
.modalias = "spi-dummy",
/* Really dummy, pass in additional chip config here */
.platform_data = NULL,
/* This defines how the controller shall handle the device */
.controller_data = &dummy_chip_info,
/* .irq - no external IRQ routed from this device */
.max_speed_hz = 1000000,
.bus_num = 0, /* Only one bus on this chip */
.chip_select = 0,
/* Means SPI_CS_HIGH, change if e.g low CS */
.mode = SPI_MODE_1 | SPI_LSB_FIRST | SPI_LOOP,
},
#endif
};
static struct pl022_ssp_controller ssp_platform_data = {
/* If you have several SPI buses this varies, we have only bus 0 */
.bus_id = 0,
/* Set this to 1 when we think we got DMA working */
.enable_dma = 0,
/*
* On the APP CPU GPIO 4, 5 and 6 are connected as generic
* chip selects for SPI. (Same on U330, U335 and U365.)
* TODO: make sure the GPIO driver can select these properly
* and do padmuxing accordingly too.
*/
.num_chipselect = 3,
};
void __init u300_spi_init(struct amba_device *adev)
{
struct pmx *pmx;
adev->dev.platform_data = &ssp_platform_data;
/*
* Setup padmuxing for SPI. Since this must always be
* compiled into the kernel, pmx is never released.
*/
pmx = pmx_get(&adev->dev, U300_APP_PMX_SPI_SETTING);
if (IS_ERR(pmx))
dev_warn(&adev->dev, "Could not get padmux handle\n");
else {
int ret;
ret = pmx_activate(&adev->dev, pmx);
if (IS_ERR_VALUE(ret))
dev_warn(&adev->dev, "Could not activate padmuxing\n");
}
}
void __init u300_spi_register_board_devices(void)
{
/* Register any SPI devices */
spi_register_board_info(u300_spi_devices, ARRAY_SIZE(u300_spi_devices));
}