--- /dev/null
+#
+# Makefile for the Linux WWAN device drivers.
+#
+# NOTE: This make file can serve as both an external Makefile (launched
+# directly by the user), or as the sub-dir Makefile used by the kernel
+# build system.
+
+# If CONFIG_SPI_TTY isn't set, we'll assume the user has never configured
+# their kernel to include this module and set up some defaults.
+#
+# NOTE: If you have previously added the SPI_TTY project to your kernel
+# and configured it for inclusion, these settings will be
+# overridden by your kernel configuration.
+ifndef CONFIG_SPI_TTY
+EXTERNAL_BUILD=y
+CONFIG_SPI_TTY=m
+CONFIG_SPI_TTY_DEBUG=n
+endif
+
+
+ifeq ($(CONFIG_SPI_TTY_DEBUG),y)
+ EXTRA_CFLAGS += -g -Wa,-adhlms=$@.lst
+endif
+
+ifdef KBUILD_EXTMOD
+ EXTRA_CFLAGS += -I$(KBUILD_EXTMOD)
+endif
+
+
+list-m :=
+list-$(CONFIG_SPI_TTY) += spi_tty
+obj-$(CONFIG_SPI_TTY) += spi_tty.o
+
+#
+# Begin dual Makefile mode here. First we provide support for when we
+# are being invoked by the kernel build system
+#
+ifneq ($(KERNELRELEASE),)
+
+EXTRA_CFLAGS += -DCONFIG_PM
+
+ifeq ($(EXTERNAL_BUILD),y)
+ifeq ($(CONFIG_SPI_TTY_DEBUG),y)
+EXTRA_CFLAGS += -DCONFIG_SPI_TTY_DEBUG
+endif
+endif
+
+else
+# Here we begin the portion that is executed if the user invoked this Makefile
+# directly.
+
+# KSRC should be set to the path to your sources
+KVER := $(shell uname -r)
+KSRC := /lib/modules/$(KVER)/build
+INSTALLDIR:=/lib/modules/$(KVER)/kernel/drivers/net/wwan/
+
+# KSRC_OUTPUT should be overridden if you are using a 2.6 kernel that
+# has it's output sent elsewhere via KBUILD_OUTPUT= or O=
+KSRC_OUTPUT := $(KSRC)
+
+PWD=$(shell pwd)
+
+VERFILE := $(KSRC_OUTPUT)/include/linux/version.h
+KERNELRELEASE := $(shell \
+ if [ -r $(VERFILE) ]; then \
+ (cat $(VERFILE); echo UTS_RELEASE) | \
+ $(CC) -I$(KSRC_OUTPUT) $(CFLAGS) -E - | \
+ tail -n 1 | \
+ xargs echo; \
+ else \
+ uname -r; \
+ fi)
+
+MODPATH := $(DESTDIR)/lib/modules/$(KERNELRELEASE)
+
+all: modules
+
+clean:
+ $(RM) -f *.mod.* *.mod *.o *.ko .*.o.cmd .*.ko.cmd *.flags .lst *.lst Module*.symvers
+ $(RM) -rf $(PWD)/tmp
+ $(RM) -rf .tmp_versions
+
+distclean: clean
+ rm -f tags TAGS
+
+TMP=$(PWD)/tmp
+MODVERDIR=$(TMP)/.tmp_versions
+
+modules:
+ mkdir -p $(MODVERDIR)
+ifdef ($(KSRC_OUTPUT)/.tmp_versions)
+ -cp $(KSRC_OUTPUT)/.tmp_versions/*.mod $(MODVERDIR)
+endif
+ifeq ($(KSRC),$(KSRC_OUTPUT)) # We're not outputting elsewhere
+ifdef ($(KSRC)/.tmp_versions)
+ -cp $(KSRC)/.tmp_versions/*.mod $(MODVERDIR)
+endif
+ $(MAKE) -C $(KSRC) M=$(PWD) MODVERDIR=$(MODVERDIR) modules
+else # We've got a kernel with seperate output, copy the config, and use O=
+ mkdir -p $(TMP)
+ cp $(KSRC_OUTPUT)/.config $(TMP)
+ $(MAKE) -C $(KSRC) M=$(PWD) MODVERDIR=$(MODVERDIR)) O=$(PWD)/tmp modules
+endif
+
+install: modules
+ modprobe -r spi_tty || true
+ install -d $(INSTALLDIR)
+ install -m 644 -c $(addsuffix .ko,$(list-m)) $(INSTALLDIR)
+ /sbin/depmod -a ${KVER}
+
+uninstall:
+ rm -rf $(addprefix $(INSTALLDIR),$(addsuffix .ko,$(list-m)))
+ /sbin/depmod -a ${KVER}
+
+endif # End of internal build
+
+.PHONY: TAGS tags
+
+RCS_FIND_IGNORE := \( -name SCCS -o -name BitKeeper -o -name .svn -o -name CVS \) -prune -o
+define all-sources
+ ( find . $(RCS_FIND_IGNORE) -name '*.[chS]' -print )
+endef
+
+TAGS:
+ $(all-sources) | etags -
+tags:
+ $(RM) -f $@
+ CTAGSF=`ctags --version | grep -i exuberant >/dev/null && echo "-I __initdata,__exitdata,EXPORT_SYMBOL,EXPORT_SYMBOL_NOVERS"`; \
+ $(all-sources) | xargs ctags $$CTAGSF -a
+
--- /dev/null
+/*
+ * spi_butterfly.c - parport-to-butterfly adapter
+ *
+ * Copyright (C) 2005 David Brownell
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/parport.h>
+
+#include <linux/sched.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi_bitbang.h>
+
+
+
+/*
+ * This uses SPI to talk with an "AVR Butterfly", which is a $US20 card
+ * with a battery powered AVR microcontroller and lots of goodies. You
+ * can use GCC to develop firmware for this.
+ *
+ * See Documentation/spi/butterfly for information about how to build
+ * and use this custom parallel port cable.
+ */
+
+/*
+ * spi_device
+ * todo:
+ * - implement SPI mode 1,2,3 is yet missing
+ * - prevent ugly handling of global butterfly structure
+ * - use serial subsystem
+ * - make stuff module configurable during runtime
+ */
+
+/* DATA output bits (pins 2..9 == D0..D7) */
+#define butterfly_nreset (1 << 1) /* pin 3 */
+
+#define spi_sck_bit (1 << 0) /* pin 2 */
+#define spi_mosi_bit (1 << 7) /* pin 9 */
+
+#define vcc_bits ((1 << 6) | (1 << 5)) /* pins 7, 8 */
+
+/* STATUS input bits */
+#define spi_miso_bit PARPORT_STATUS_BUSY /* pin 11 */
+
+/* CONTROL output bits */
+#define spi_cs_bit PARPORT_CONTROL_SELECT /* pin 17 */
+
+
+
+static inline struct butterfly *spidev_to_pp(struct spi_device *spi)
+{
+ return spi->controller_data;
+}
+
+
+struct butterfly {
+ /* REVISIT ... for now, this must be first */
+ struct spi_bitbang bitbang;
+
+ struct parport *port;
+ struct pardevice *pd;
+
+ u8 lastbyte;
+
+ struct spi_message *msg;
+ struct spi_device *butterfly;
+ struct spi_board_info info[2];
+
+};
+
+/*----------------------------------------------------------------------*/
+
+static inline void
+setsck(struct spi_device *spi, int is_on)
+{
+ struct butterfly *pp = spidev_to_pp(spi);
+ u8 bit, byte = pp->lastbyte;
+
+ bit = spi_sck_bit;
+
+ if (is_on)
+ byte |= bit;
+ else
+ byte &= ~bit;
+ parport_write_data(pp->port, byte);
+ pp->lastbyte = byte;
+}
+
+static inline void
+setmosi(struct spi_device *spi, int is_on)
+{
+ struct butterfly *pp = spidev_to_pp(spi);
+ u8 bit, byte = pp->lastbyte;
+
+ bit = spi_mosi_bit;
+
+ if (is_on)
+ byte |= bit;
+ else
+ byte &= ~bit;
+ parport_write_data(pp->port, byte);
+ pp->lastbyte = byte;
+}
+
+static inline int getmiso(struct spi_device *spi)
+{
+ struct butterfly *pp = spidev_to_pp(spi);
+ int value;
+ u8 bit;
+
+ bit = spi_miso_bit;
+
+ /* only STATUS_BUSY is NOT negated */
+ value = !(parport_read_status(pp->port) & bit);
+ return (bit == PARPORT_STATUS_BUSY) ? value : !value;
+}
+
+static void butterfly_chipselect(struct spi_device *spi, int value)
+{
+ struct butterfly *pp = spidev_to_pp(spi);
+
+ /* set default clock polarity */
+ if (value != BITBANG_CS_INACTIVE)
+ setsck(spi, spi->mode & SPI_CPOL);
+
+ /* here, value == "activate or not";
+ * most PARPORT_CONTROL_* bits are negated, so we must
+ * morph it to value == "bit value to write in control register"
+ */
+ if (spi_cs_bit == PARPORT_CONTROL_INIT)
+ value = !value;
+
+ parport_frob_control(pp->port, spi_cs_bit, value ? spi_cs_bit : 0);
+}
+
+
+/* we only needed to implement one mode here, and choose SPI_MODE_0 */
+
+#define spidelay(X) do{}while(0)
+//#define spidelay ndelay
+
+#define EXPAND_BITBANG_TXRX
+#include <linux/spi/spi_bitbang.h>
+
+static u32
+butterfly_txrx_word_mode0(struct spi_device *spi,
+ unsigned nsecs,
+ u32 word, u8 bits)
+{
+ return bitbang_txrx_be_cpha0(spi, nsecs, 0, word, bits);
+}
+
+/*----------------------------------------------------------------------*/
+
+/* REVISIT remove this ugly global and its "only one" limitation */
+static struct butterfly *butterfly;
+
+static void butterfly_attach(struct parport *p)
+{
+ struct pardevice *pd;
+ int status;
+ struct butterfly *pp;
+ struct spi_master *master;
+ struct device *dev = p->physport->dev;
+
+ if (butterfly || !dev)
+ return;
+
+ /* REVISIT: this just _assumes_ a butterfly is there ... no probe,
+ * and no way to be selective about what it binds to.
+ */
+
+ master = spi_alloc_master(dev, sizeof *pp);
+ if (!master) {
+ status = -ENOMEM;
+ goto done;
+ }
+ pp = spi_master_get_devdata(master);
+
+ /*
+ * SPI and bitbang hookup
+ *
+ * use default setup(), cleanup(), and transfer() methods; and
+ * only bother implementing mode 0. Start it later.
+ */
+ master->bus_num = 42; // hard coded?!?
+ master->num_chipselect = 2; // hard coded?!?
+
+ pp->bitbang.master = spi_master_get(master);
+ pp->bitbang.chipselect = butterfly_chipselect;
+ pp->bitbang.txrx_word[SPI_MODE_0] = butterfly_txrx_word_mode0;
+
+ /*
+ * parport hookup
+ */
+ pp->port = p;
+ pd = parport_register_device(p, "spi_butterfly",
+ NULL, NULL, NULL,
+ 0 /* FLAGS */, pp);
+ if (!pd) {
+ status = -ENOMEM;
+ goto clean0;
+ }
+ pp->pd = pd;
+
+ status = parport_claim(pd);
+ if (status < 0)
+ goto clean1;
+
+ /*
+ * Butterfly reset, powerup, run firmware
+ */
+ pr_debug("%s: powerup/reset Butterfly\n", p->name);
+
+ /* nCS for dataflash (this bit is inverted on output) */
+ parport_frob_control(pp->port, spi_cs_bit, 0);
+
+ /* stabilize power with chip in reset (nRESET), and
+ * spi_sck_bit clear (CPOL=0)
+ */
+ pp->lastbyte |= vcc_bits;
+ parport_write_data(pp->port, pp->lastbyte);
+ msleep(5);
+
+ /* take it out of reset; assume long reset delay */
+ pp->lastbyte |= butterfly_nreset;
+ parport_write_data(pp->port, pp->lastbyte);
+ msleep(100);
+
+
+ /*
+ * Start SPI ... for now, hide that we're two physical busses.
+ */
+ status = spi_bitbang_start(&pp->bitbang);
+ if (status < 0)
+ goto clean2;
+
+ /* Bus 1 lets us talk to at45db041b (firmware disables AVR SPI), AVR
+ * (firmware resets at45, acts as spi slave) or neither (we ignore
+ * both, AVR uses AT45). Here we expect firmware for the first option.
+ */
+
+ pp->info[0].max_speed_hz = 15 * 1000 * 1000;
+
+ strcpy(pp->info[0].modalias, "spi_tty"); // name length check ! < KOBJ_NAME_LEN
+ pp->info[0].platform_data = NULL; // here we should add data structures for subsystem driver ???
+ pp->info[0].chip_select = 1; // 0: .. 1:
+ pp->info[0].controller_data = pp; /* save my structure for later use */
+ pp->butterfly = spi_new_device(pp->bitbang.master, &pp->info[0]);
+ if (pp->butterfly)
+ pr_debug("%s: dataflash at %s\n", p->name,
+ pp->butterfly->dev.bus_id);
+
+ // dev_info(_what?_, ...)
+ pr_info("%s: AVR Butterfly\n", p->name);
+
+
+ /* get spi_bitbang_transfer either via global Symbol, or better
+ * ask it from the driver structure
+ */
+ pp->msg = spi_message_alloc(1, GFP_KERNEL);
+ if (master) { /* the same address is also saved in pp->bitbang.master or pp->butterfly->master */
+ struct spi_message *spi_msg;
+ spi_msg = pp->msg;
+ if (spi_msg) {
+ // spi_message_init(spi_msg);
+ pr_info("Alloc SPI message buffer\n");
+ spi_msg->spi = pp->butterfly;
+ spi_msg->actual_length = 1;
+#if 0
+ spi_msg->list_head ... Addresse der ersten SPI transfer struct
+
+
+ spi_msg->tx_buf = ;
+ spi_msg->len = 1;
+ spi_msg->cs_change = 1;
+ spi_msg->delay_usecs = 0;
+
+ /* fill up message */
+ master->transfer(pp->butterfly, spi_msg);
+#endif
+ }
+ }
+ butterfly = pp;
+ return;
+
+clean2:
+ /* turn off VCC */
+ parport_write_data(pp->port, 0);
+
+ parport_release(pp->pd);
+clean1:
+ parport_unregister_device(pd);
+clean0:
+ (void) spi_master_put(pp->bitbang.master);
+done:
+ pr_debug("%s: butterfly probe, fail %d\n", p->name, status);
+}
+
+static void butterfly_detach(struct parport *p)
+{
+ struct butterfly *pp;
+ int status;
+
+ /* FIXME this global is ugly ... but, how to quickly get from
+ * the parport to the "struct butterfly" associated with it?
+ * "old school" driver-internal device lists?
+ */
+ if (!butterfly || butterfly->port != p)
+ return;
+ pp = butterfly;
+ if (pp->msg) {
+ spi_message_free(pp->msg);
+ pr_info("Dealloc SPI message buffer\n");
+ }
+ butterfly = NULL;
+
+ /* stop() unregisters child devices too */
+ status = spi_bitbang_stop(&pp->bitbang);
+
+ /* turn off VCC */
+ parport_write_data(pp->port, 0);
+ msleep(10);
+
+ parport_release(pp->pd);
+ parport_unregister_device(pp->pd);
+
+ (void) spi_master_put(pp->bitbang.master);
+}
+
+static struct parport_driver butterfly_driver = {
+ .name = "spi_butterfly",
+ .attach = butterfly_attach,
+ .detach = butterfly_detach,
+};
+
+
+static int __init butterfly_init(void)
+{
+ return parport_register_driver(&butterfly_driver);
+}
+device_initcall(butterfly_init);
+
+static void __exit butterfly_exit(void)
+{
+ parport_unregister_driver(&butterfly_driver);
+}
+module_exit(butterfly_exit);
+
+MODULE_DESCRIPTION("Parport Adapter driver for SPI tty Butterfly");
+MODULE_LICENSE("GPL");
projects / pub / spi-gpio-pp.git / commitdiff