diff options
author | Linus Walleij <linus.walleij@stericsson.com> | 2009-08-14 10:59:05 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2009-08-15 15:36:29 +0100 |
commit | c7c8c78fdf6e9bd65d8ee879115dc2cd5d9fd0dc (patch) | |
tree | 91f59159fed1c22277c72e2529317561778657b9 /arch/arm | |
parent | df1e0520f9434b5b771c854a13dd928727d8673a (diff) | |
download | linux-c7c8c78fdf6e9bd65d8ee879115dc2cd5d9fd0dc.tar.bz2 |
ARM: 5667/3: U300 SSP/SPI board setup and test
This adds a U300 board configuration for the PL022 SSP/SPI
PrimeCell driver recently merged to the 2.6.31-rc series.
Further it adds a dummy loopback SPI chip that can be used
for testing the SPI functionality on a running system using
the loopback mode of PL022.
Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'arch/arm')
-rw-r--r-- | arch/arm/mach-u300/Kconfig | 12 | ||||
-rw-r--r-- | arch/arm/mach-u300/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/mach-u300/core.c | 6 | ||||
-rw-r--r-- | arch/arm/mach-u300/dummyspichip.c | 290 | ||||
-rw-r--r-- | arch/arm/mach-u300/spi.c | 124 | ||||
-rw-r--r-- | arch/arm/mach-u300/spi.h | 26 |
6 files changed, 460 insertions, 0 deletions
diff --git a/arch/arm/mach-u300/Kconfig b/arch/arm/mach-u300/Kconfig index 337b9aabce49..801b21e7f677 100644 --- a/arch/arm/mach-u300/Kconfig +++ b/arch/arm/mach-u300/Kconfig @@ -81,6 +81,18 @@ config MACH_U300_SEMI_IS_SHARED Memory Interface) from both from access and application side. +config MACH_U300_SPIDUMMY + bool "SSP/SPI dummy chip" + select SPI + select SPI_MASTER + select SPI_PL022 + help + This creates a small kernel module that creates a dummy + SPI device to be used for loopback tests. Regularly used + to test reference designs. If you're not testing SPI, + you don't need it. Selecting this will activate the + SPI framework and ARM PL022 support. + comment "All the settings below must match the bootloader's settings" config MACH_U300_ACCESS_MEM_SIZE diff --git a/arch/arm/mach-u300/Makefile b/arch/arm/mach-u300/Makefile index 24950e0df4b4..4941f89ea798 100644 --- a/arch/arm/mach-u300/Makefile +++ b/arch/arm/mach-u300/Makefile @@ -9,3 +9,5 @@ obj- := obj-$(CONFIG_ARCH_U300) += u300.o obj-$(CONFIG_MMC) += mmc.o +obj-$(CONFIG_SPI_PL022) += spi.o +obj-$(CONFIG_MACH_U300_SPIDUMMY) += dummyspichip.o diff --git a/arch/arm/mach-u300/core.c b/arch/arm/mach-u300/core.c index 89b3ccf35e1b..38d08a1c25d0 100644 --- a/arch/arm/mach-u300/core.c +++ b/arch/arm/mach-u300/core.c @@ -32,6 +32,7 @@ #include "clock.h" #include "mmc.h" +#include "spi.h" /* * Static I/O mappings that are needed for booting the U300 platforms. The @@ -611,6 +612,8 @@ void __init u300_init_devices(void) /* Wait for the PLL208 to lock if not locked in yet */ while (!(readw(U300_SYSCON_VBASE + U300_SYSCON_CSR) & U300_SYSCON_CSR_PLL208_LOCK_IND)); + /* Initialize SPI device with some board specifics */ + u300_spi_init(&pl022_device); /* Register the AMBA devices in the AMBA bus abstraction layer */ u300_clock_primecells(); @@ -622,6 +625,9 @@ void __init u300_init_devices(void) u300_assign_physmem(); + /* Register subdevices on the SPI bus */ + u300_spi_register_board_devices(); + /* Register the platform devices */ platform_add_devices(platform_devs, ARRAY_SIZE(platform_devs)); diff --git a/arch/arm/mach-u300/dummyspichip.c b/arch/arm/mach-u300/dummyspichip.c new file mode 100644 index 000000000000..962f9de454de --- /dev/null +++ b/arch/arm/mach-u300/dummyspichip.c @@ -0,0 +1,290 @@ +/* + * arch/arm/mach-u300/dummyspichip.c + * + * Copyright (C) 2007-2009 ST-Ericsson AB + * License terms: GNU General Public License (GPL) version 2 + * This is a dummy loopback SPI "chip" used for testing SPI. + * Author: Linus Walleij <linus.walleij@stericsson.com> + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/device.h> +#include <linux/err.h> +#include <linux/sysfs.h> +#include <linux/mutex.h> +#include <linux/spi/spi.h> +#include <linux/dma-mapping.h> +/* + * WARNING! Do not include this pl022-specific controller header + * for any generic driver. It is only done in this dummy chip + * because we alter the chip configuration in order to test some + * different settings on the loopback device. Normal chip configs + * shall be STATIC and not altered by the driver! + */ +#include <linux/amba/pl022.h> + +struct dummy { + struct device *dev; + struct mutex lock; +}; + +#define DMA_TEST_SIZE 2048 + +/* When we cat /sys/bus/spi/devices/spi0.0/looptest this will be triggered */ +static ssize_t dummy_looptest(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct spi_device *spi = to_spi_device(dev); + struct dummy *p_dummy = dev_get_drvdata(&spi->dev); + + /* + * WARNING! Do not dereference the chip-specific data in any normal + * driver for a chip. It is usually STATIC and shall not be read + * or written to. Your chip driver should NOT depend on fields in this + * struct, this is just used here to alter the behaviour of the chip + * in order to perform tests. + */ + struct pl022_config_chip *chip_info = spi->controller_data; + int status; + u8 txbuf[14] = {0xDE, 0xAD, 0xBE, 0xEF, 0x2B, 0xAD, + 0xCA, 0xFE, 0xBA, 0xBE, 0xB1, 0x05, + 0xF0, 0x0D}; + u8 rxbuf[14]; + u8 *bigtxbuf_virtual; + u8 *bigrxbuf_virtual; + + if (mutex_lock_interruptible(&p_dummy->lock)) + return -ERESTARTSYS; + + bigtxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL); + if (bigtxbuf_virtual == NULL) { + status = -ENOMEM; + goto out; + } + bigrxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL); + + /* Fill TXBUF with some happy pattern */ + memset(bigtxbuf_virtual, 0xAA, DMA_TEST_SIZE); + + /* + * Force chip to 8 bit mode + * WARNING: NEVER DO THIS IN REAL DRIVER CODE, THIS SHOULD BE STATIC! + */ + chip_info->data_size = SSP_DATA_BITS_8; + /* You should NOT DO THIS EITHER */ + spi->master->setup(spi); + + /* Now run the tests for 8bit mode */ + pr_info("Simple test 1: write 0xAA byte, read back garbage byte " + "in 8bit mode\n"); + status = spi_w8r8(spi, 0xAA); + if (status < 0) + pr_warning("Siple test 1: FAILURE: spi_write_then_read " + "failed with status %d\n", status); + else + pr_info("Simple test 1: SUCCESS!\n"); + + pr_info("Simple test 2: write 8 bytes, read back 8 bytes garbage " + "in 8bit mode (full FIFO)\n"); + status = spi_write_then_read(spi, &txbuf[0], 8, &rxbuf[0], 8); + if (status < 0) + pr_warning("Simple test 2: FAILURE: spi_write_then_read() " + "failed with status %d\n", status); + else + pr_info("Simple test 2: SUCCESS!\n"); + + pr_info("Simple test 3: write 14 bytes, read back 14 bytes garbage " + "in 8bit mode (see if we overflow FIFO)\n"); + status = spi_write_then_read(spi, &txbuf[0], 14, &rxbuf[0], 14); + if (status < 0) + pr_warning("Simple test 3: FAILURE: failed with status %d " + "(probably FIFO overrun)\n", status); + else + pr_info("Simple test 3: SUCCESS!\n"); + + pr_info("Simple test 4: write 8 bytes with spi_write(), read 8 " + "bytes garbage with spi_read() in 8bit mode\n"); + status = spi_write(spi, &txbuf[0], 8); + if (status < 0) + pr_warning("Simple test 4 step 1: FAILURE: spi_write() " + "failed with status %d\n", status); + else + pr_info("Simple test 4 step 1: SUCCESS!\n"); + status = spi_read(spi, &rxbuf[0], 8); + if (status < 0) + pr_warning("Simple test 4 step 2: FAILURE: spi_read() " + "failed with status %d\n", status); + else + pr_info("Simple test 4 step 2: SUCCESS!\n"); + + pr_info("Simple test 5: write 14 bytes with spi_write(), read " + "14 bytes garbage with spi_read() in 8bit mode\n"); + status = spi_write(spi, &txbuf[0], 14); + if (status < 0) + pr_warning("Simple test 5 step 1: FAILURE: spi_write() " + "failed with status %d (probably FIFO overrun)\n", + status); + else + pr_info("Simple test 5 step 1: SUCCESS!\n"); + status = spi_read(spi, &rxbuf[0], 14); + if (status < 0) + pr_warning("Simple test 5 step 2: FAILURE: spi_read() " + "failed with status %d (probably FIFO overrun)\n", + status); + else + pr_info("Simple test 5: SUCCESS!\n"); + + pr_info("Simple test 6: write %d bytes with spi_write(), " + "read %d bytes garbage with spi_read() in 8bit mode\n", + DMA_TEST_SIZE, DMA_TEST_SIZE); + status = spi_write(spi, &bigtxbuf_virtual[0], DMA_TEST_SIZE); + if (status < 0) + pr_warning("Simple test 6 step 1: FAILURE: spi_write() " + "failed with status %d (probably FIFO overrun)\n", + status); + else + pr_info("Simple test 6 step 1: SUCCESS!\n"); + status = spi_read(spi, &bigrxbuf_virtual[0], DMA_TEST_SIZE); + if (status < 0) + pr_warning("Simple test 6 step 2: FAILURE: spi_read() " + "failed with status %d (probably FIFO overrun)\n", + status); + else + pr_info("Simple test 6: SUCCESS!\n"); + + + /* + * Force chip to 16 bit mode + * WARNING: NEVER DO THIS IN REAL DRIVER CODE, THIS SHOULD BE STATIC! + */ + chip_info->data_size = SSP_DATA_BITS_16; + /* You should NOT DO THIS EITHER */ + spi->master->setup(spi); + + pr_info("Simple test 7: write 0xAA byte, read back garbage byte " + "in 16bit bus mode\n"); + status = spi_w8r8(spi, 0xAA); + if (status == -EIO) + pr_info("Simple test 7: SUCCESS! (expected failure with " + "status EIO)\n"); + else if (status < 0) + pr_warning("Siple test 7: FAILURE: spi_write_then_read " + "failed with status %d\n", status); + else + pr_warning("Siple test 7: FAILURE: spi_write_then_read " + "succeeded but it was expected to fail!\n"); + + pr_info("Simple test 8: write 8 bytes, read back 8 bytes garbage " + "in 16bit mode (full FIFO)\n"); + status = spi_write_then_read(spi, &txbuf[0], 8, &rxbuf[0], 8); + if (status < 0) + pr_warning("Simple test 8: FAILURE: spi_write_then_read() " + "failed with status %d\n", status); + else + pr_info("Simple test 8: SUCCESS!\n"); + + pr_info("Simple test 9: write 14 bytes, read back 14 bytes garbage " + "in 16bit mode (see if we overflow FIFO)\n"); + status = spi_write_then_read(spi, &txbuf[0], 14, &rxbuf[0], 14); + if (status < 0) + pr_warning("Simple test 9: FAILURE: failed with status %d " + "(probably FIFO overrun)\n", status); + else + pr_info("Simple test 9: SUCCESS!\n"); + + pr_info("Simple test 10: write %d bytes with spi_write(), " + "read %d bytes garbage with spi_read() in 16bit mode\n", + DMA_TEST_SIZE, DMA_TEST_SIZE); + status = spi_write(spi, &bigtxbuf_virtual[0], DMA_TEST_SIZE); + if (status < 0) + pr_warning("Simple test 10 step 1: FAILURE: spi_write() " + "failed with status %d (probably FIFO overrun)\n", + status); + else + pr_info("Simple test 10 step 1: SUCCESS!\n"); + + status = spi_read(spi, &bigrxbuf_virtual[0], DMA_TEST_SIZE); + if (status < 0) + pr_warning("Simple test 10 step 2: FAILURE: spi_read() " + "failed with status %d (probably FIFO overrun)\n", + status); + else + pr_info("Simple test 10: SUCCESS!\n"); + + status = sprintf(buf, "loop test complete\n"); + kfree(bigrxbuf_virtual); + kfree(bigtxbuf_virtual); + out: + mutex_unlock(&p_dummy->lock); + return status; +} + +static DEVICE_ATTR(looptest, S_IRUGO, dummy_looptest, NULL); + +static int __devinit pl022_dummy_probe(struct spi_device *spi) +{ + struct dummy *p_dummy; + int status; + + dev_info(&spi->dev, "probing dummy SPI device\n"); + + p_dummy = kzalloc(sizeof *p_dummy, GFP_KERNEL); + if (!p_dummy) + return -ENOMEM; + + dev_set_drvdata(&spi->dev, p_dummy); + mutex_init(&p_dummy->lock); + + /* sysfs hook */ + status = device_create_file(&spi->dev, &dev_attr_looptest); + if (status) { + dev_dbg(&spi->dev, "device_create_file looptest failure.\n"); + goto out_dev_create_looptest_failed; + } + + return 0; + +out_dev_create_looptest_failed: + dev_set_drvdata(&spi->dev, NULL); + kfree(p_dummy); + return status; +} + +static int __devexit pl022_dummy_remove(struct spi_device *spi) +{ + struct dummy *p_dummy = dev_get_drvdata(&spi->dev); + + dev_info(&spi->dev, "removing dummy SPI device\n"); + device_remove_file(&spi->dev, &dev_attr_looptest); + dev_set_drvdata(&spi->dev, NULL); + kfree(p_dummy); + + return 0; +} + +static struct spi_driver pl022_dummy_driver = { + .driver = { + .name = "spi-dummy", + .owner = THIS_MODULE, + }, + .probe = pl022_dummy_probe, + .remove = __devexit_p(pl022_dummy_remove), +}; + +static int __init pl022_init_dummy(void) +{ + return spi_register_driver(&pl022_dummy_driver); +} + +static void __exit pl022_exit_dummy(void) +{ + spi_unregister_driver(&pl022_dummy_driver); +} + +module_init(pl022_init_dummy); +module_exit(pl022_exit_dummy); + +MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>"); +MODULE_DESCRIPTION("PL022 SSP/SPI DUMMY Linux driver"); +MODULE_LICENSE("GPL"); diff --git a/arch/arm/mach-u300/spi.c b/arch/arm/mach-u300/spi.c new file mode 100644 index 000000000000..307d007ea7f3 --- /dev/null +++ b/arch/arm/mach-u300/spi.c @@ -0,0 +1,124 @@ +/* + * 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 = { + /* Nominally this is LOOPBACK_DISABLED, but this is our dummy chip! */ + .lbm = LOOPBACK_ENABLED, + /* + * 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, + /* LSB first */ + .endian_tx = SSP_TX_LSB, + .endian_rx = SSP_RX_LSB, + .data_size = SSP_DATA_BITS_8, /* used to be 12 in some default */ + .rx_lev_trig = SSP_RX_1_OR_MORE_ELEM, + .tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC, + .clk_phase = SSP_CLK_FALLING_EDGE, + .clk_pol = SSP_CLK_POL_IDLE_LOW, + .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 = 0, + }, +#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)); +} diff --git a/arch/arm/mach-u300/spi.h b/arch/arm/mach-u300/spi.h new file mode 100644 index 000000000000..bd3d867e240f --- /dev/null +++ b/arch/arm/mach-u300/spi.h @@ -0,0 +1,26 @@ +/* + * arch/arm/mach-u300/spi.h + * + * Copyright (C) 2009 ST-Ericsson AB + * License terms: GNU General Public License (GPL) version 2 + * + * Author: Linus Walleij <linus.walleij@stericsson.com> + */ +#ifndef SPI_H +#define SPI_H +#include <linux/amba/bus.h> + +#ifdef CONFIG_SPI_PL022 +void __init u300_spi_init(struct amba_device *adev); +void __init u300_spi_register_board_devices(void); +#else +/* Compile out SPI support if PL022 is not selected */ +static inline void __init u300_spi_init(struct amba_device *adev) +{ +} +static inline void __init u300_spi_register_board_devices(void) +{ +} +#endif + +#endif |