This patch implements probing for the bus and reporting the number of available expansion slots.
Signed-off-by: Sergei Ianovich <[email protected]> --- Documentation/misc-devices/lp8x4x_bus.txt | 30 ++++++ arch/arm/configs/lp8x4x_defconfig | 1 + arch/arm/mach-pxa/include/mach/lp8x4x.h | 1 + arch/arm/mach-pxa/lp8x4x.c | 18 ++++ drivers/misc/Kconfig | 12 +++ drivers/misc/Makefile | 1 + drivers/misc/lp8x4x_bus.c | 165 ++++++++++++++++++++++++++++++ 7 files changed, 228 insertions(+) create mode 100644 Documentation/misc-devices/lp8x4x_bus.txt create mode 100644 drivers/misc/lp8x4x_bus.c diff --git a/Documentation/misc-devices/lp8x4x_bus.txt b/Documentation/misc-devices/lp8x4x_bus.txt new file mode 100644 index 0000000..f5392b3 --- /dev/null +++ b/Documentation/misc-devices/lp8x4x_bus.txt @@ -0,0 +1,30 @@ +Kernel driver lpx8x4x_bus +====================== + +Supported hardare: +Custom parallel bus on ICP DAS LP-8x4x industrial computers + +Data sheet: +Not freely available + +Author: +Sergei Ianovich <[email protected]> + +Description +----------- + +http://www.icpdas.com/root/product/solutions/pac/linpac/lp-8x4x_hardware.html + +LP-8x4x is an ARM-based industrial computer with a custom parallel bus to +connect expansion modules with digital input/output, analog input/output, +serial, CAN and other types of ports. + +The bus is implemented by a FPGA. + +SYSFS +----- + +/sys/bus/icpdas/devices/backplane: + +slot_count + RO - shows total number of expansion slots on the device diff --git a/arch/arm/configs/lp8x4x_defconfig b/arch/arm/configs/lp8x4x_defconfig index d297a67..5f2b842 100644 --- a/arch/arm/configs/lp8x4x_defconfig +++ b/arch/arm/configs/lp8x4x_defconfig @@ -921,6 +921,7 @@ CONFIG_BLK_DEV_LOOP_MIN_COUNT=2 # CONFIG_BMP085_I2C is not set # CONFIG_USB_SWITCH_FSA9480 is not set # CONFIG_SRAM is not set +CONFIG_LP8X4X_BUS=m # CONFIG_C2PORT is not set # diff --git a/arch/arm/mach-pxa/include/mach/lp8x4x.h b/arch/arm/mach-pxa/include/mach/lp8x4x.h index 4d5474e..5d289bf 100644 --- a/arch/arm/mach-pxa/include/mach/lp8x4x.h +++ b/arch/arm/mach-pxa/include/mach/lp8x4x.h @@ -53,6 +53,7 @@ #define LP8X4X_TTYS0_QUIRK 0x17009030 #define LP8X4X_TTYS1_QUIRK 0x17009032 #define LP8X4X_TTYS2_QUIRK 0x17009034 +#define LP8X4X_MOD_NUM 0x17009046 #define LP8X4X_TTYS0_IOMEM 0x17009050 #define LP8X4X_TTYS1_IOMEM 0x17009060 #define LP8X4X_TTYS2_IOMEM 0x17009070 diff --git a/arch/arm/mach-pxa/lp8x4x.c b/arch/arm/mach-pxa/lp8x4x.c index 47a8776..38482d3 100644 --- a/arch/arm/mach-pxa/lp8x4x.c +++ b/arch/arm/mach-pxa/lp8x4x.c @@ -418,6 +418,23 @@ static struct platform_device lp8x4x_ds1302_device[] = { }, }; +static struct resource lp8x4x_bus_resources[] = { + [0] = { + .start = LP8X4X_MOD_NUM, + .end = LP8X4X_MOD_NUM, + .flags = IORESOURCE_MEM, + }, +}; + +static struct platform_device lp8x4x_bus_device[] = { + { + .name = "lp8x4x-bus", + .id = 0, + .resource = &lp8x4x_bus_resources[0], + .num_resources = 1, + }, +}; + static struct platform_device *lp8x4x_devices[] __initdata = { &lp8x4x_flash_device[0], &lp8x4x_flash_device[1], @@ -425,6 +442,7 @@ static struct platform_device *lp8x4x_devices[] __initdata = { &lp8x4x_dm9000_device[0], &lp8x4x_dm9000_device[1], &lp8x4x_ds1302_device[0], + &lp8x4x_bus_device[0], }; static struct pxaohci_platform_data lp8x4x_ohci_platform_data = { diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig index a3e291d..85676c4 100644 --- a/drivers/misc/Kconfig +++ b/drivers/misc/Kconfig @@ -515,6 +515,18 @@ config SRAM the genalloc API. It is supposed to be used for small on-chip SRAM areas found on many SoCs. +config LP8X4X_BUS + tristate "ICP DAS LP-8x4x industrial IO bus" + depends on MACH_LP8X4X && SYSFS + ---help--- + This is a driver for ICP DAS LP-8x4x programmable automation + controller. It exposes a custom parallel bus. The bus services + data acquisition and control modules. + + Say N, unless you plan to run this kernel on a LP-8x4x system. + + If you say M here, the module will be called lp8x4x_bus. + source "drivers/misc/c2port/Kconfig" source "drivers/misc/eeprom/Kconfig" source "drivers/misc/cb710/Kconfig" diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile index f45473e..7578cff 100644 --- a/drivers/misc/Makefile +++ b/drivers/misc/Makefile @@ -53,3 +53,4 @@ obj-$(CONFIG_VMWARE_VMCI) += vmw_vmci/ obj-$(CONFIG_LATTICE_ECP3_CONFIG) += lattice-ecp3-config.o obj-$(CONFIG_SRAM) += sram.o obj-y += mic/ +obj-$(CONFIG_LP8X4X_BUS) += lp8x4x_bus.o diff --git a/drivers/misc/lp8x4x_bus.c b/drivers/misc/lp8x4x_bus.c new file mode 100644 index 0000000..9cd840e --- /dev/null +++ b/drivers/misc/lp8x4x_bus.c @@ -0,0 +1,165 @@ +/* + * linux/misc/lp8x4x_bus.c + * + * Support for ICP DAS LP-8x4x programmable automation controller bus + * Copyright (C) 2013 Sergei Ianovich <[email protected]> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation or any later version. + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/list.h> +#include <linux/slab.h> +#include <linux/gpio.h> + +#include <mach/mfp-pxa27x.h> +#include <mach/lp8x4x.h> +#include <asm/system_info.h> + +#define MODULE_NAME "lp8x4x-bus" +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sergei Ianovich <[email protected]>"); +MODULE_DESCRIPTION("ICP DAS LP-8x4x parallel bus driver"); + +struct lp8x4x_master { + unsigned int slot_count; + void *count_addr; + struct device dev; +}; + +static int lp8x4x_match(struct device *dev, struct device_driver *drv) +{ + return 1; +} + +static struct bus_type lp8x4x_bus_type = { + .name = "icpdas", + .match = lp8x4x_match, +}; + +static void lp8x4x_master_release(struct device *dev) +{ + struct lp8x4x_master *m = container_of(dev, struct lp8x4x_master, dev); + BUG_ON(!dev); + + kfree(m); +} + +static ssize_t slot_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct lp8x4x_master *m = container_of(dev, struct lp8x4x_master, dev); + + return sprintf(buf, "%u\n", m->slot_count); +} + +static DEVICE_ATTR_RO(slot_count); + +static struct attribute *master_dev_attrs[] = { + &dev_attr_slot_count.attr, + NULL, +}; +ATTRIBUTE_GROUPS(master_dev); + + +static void devm_lp8x4x_bus_release(struct device *dev, void *res) +{ + struct lp8x4x_master *m = *(struct lp8x4x_master **)res; + void *mem = m->count_addr; + + dev_info(dev, "releasing devices\n"); + device_unregister(&m->dev); + bus_unregister(&lp8x4x_bus_type); + iounmap(mem); +} + +static int __init lp8x4x_bus_probe(struct platform_device *pdev) +{ + struct lp8x4x_master *m, **p; + struct resource *res; + int err = 0; + + m = kzalloc(sizeof(*m), GFP_KERNEL); + if (!m) + return -ENOMEM; + + p = devres_alloc(devm_lp8x4x_bus_release, sizeof(*p), GFP_KERNEL); + if (!m) { + err = -ENOMEM; + goto err1; + } + *p = m; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + err = -ENODEV; + goto err2; + } + + m->count_addr = ioremap(res->start, resource_size(res)); + if (!m->count_addr) { + dev_err(&pdev->dev, "Failed to ioremap %p\n", + m->count_addr); + err = -EFAULT; + goto err2; + } + + m->slot_count = ioread8(m->count_addr); + switch (m->slot_count) { + case 1: + case 4: + break; + case 7: + m->slot_count = 8; + break; + default: + dev_info(&pdev->dev, "unexpected slot number(%u)", + m->slot_count); + goto err3; + }; + + dev_info(&pdev->dev, "found bus with up to %u slots\n", m->slot_count); + + err = bus_register(&lp8x4x_bus_type); + if (err < 0) { + dev_err(&pdev->dev, "failed to register bus type\n"); + goto err3; + } + + m->dev.bus = &lp8x4x_bus_type; + dev_set_name(&m->dev, "backplane"); + m->dev.parent = &pdev->dev; + m->dev.release = lp8x4x_master_release; + m->dev.groups = master_dev_groups; + + err = device_register(&m->dev); + if (err < 0) { + dev_err(&pdev->dev, "failed to register backplane device\n"); + goto err4; + } + + devres_add(&pdev->dev, p); + return 0; + +err4: + bus_unregister(&lp8x4x_bus_type); +err3: + iounmap(m->count_addr); +err2: + devres_free(p); +err1: + kfree(m); + return err; +} + +static struct platform_driver lp8x4x_bus_driver = { + .driver = { + .name = MODULE_NAME, + .owner = THIS_MODULE, + }, +}; + +module_platform_driver_probe(lp8x4x_bus_driver, lp8x4x_bus_probe); -- 1.8.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
