Add c2 port support
C2port implements a two wire serial communication protocol (bit
banging) designed to enable in-system programming, debugging, and
boundary-scan testing on low pin-count Silicon Labs devices.
Currently this code supports only flash programming through sysfs
interface but extensions shoud be easy to add.
Signed-off-by: Rodolfo Giometti <giometti@linux.it>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/Documentation/ABI/testing/sysfs-c2port b/Documentation/ABI/testing/sysfs-c2port
new file mode 100644
index 0000000..716cffc
--- /dev/null
+++ b/Documentation/ABI/testing/sysfs-c2port
@@ -0,0 +1,88 @@
+What: /sys/class/c2port/
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/ directory will contain files and
+ directories that will provide a unified interface to
+ the C2 port interface.
+
+What: /sys/class/c2port/c2portX
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/ directory is related to X-th
+ C2 port into the system. Each directory will contain files to
+ manage and control its C2 port.
+
+What: /sys/class/c2port/c2portX/access
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/access file enable the access
+ to the C2 port from the system. No commands can be sent
+ till this entry is set to 0.
+
+What: /sys/class/c2port/c2portX/dev_id
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/dev_id file show the device ID
+ of the connected micro.
+
+What: /sys/class/c2port/c2portX/flash_access
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/flash_access file enable the
+ access to the on-board flash of the connected micro.
+ No commands can be sent till this entry is set to 0.
+
+What: /sys/class/c2port/c2portX/flash_block_size
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/flash_block_size file show
+ the on-board flash block size of the connected micro.
+
+What: /sys/class/c2port/c2portX/flash_blocks_num
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/flash_blocks_num file show
+ the on-board flash blocks number of the connected micro.
+
+What: /sys/class/c2port/c2portX/flash_data
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/flash_data file export
+ the content of the on-board flash of the connected micro.
+
+What: /sys/class/c2port/c2portX/flash_erase
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/flash_erase file execute
+ the "erase" command on the on-board flash of the connected
+ micro.
+
+What: /sys/class/c2port/c2portX/flash_erase
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/flash_erase file show the
+ on-board flash size of the connected micro.
+
+What: /sys/class/c2port/c2portX/reset
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/reset file execute a "reset"
+ command on the connected micro.
+
+What: /sys/class/c2port/c2portX/rev_id
+Date: October 2008
+Contact: Rodolfo Giometti <giometti@linux.it>
+Description:
+ The /sys/class/c2port/c2portX/rev_id file show the revision ID
+ of the connected micro.
diff --git a/Documentation/c2port.txt b/Documentation/c2port.txt
new file mode 100644
index 0000000..d9bf93e
--- /dev/null
+++ b/Documentation/c2port.txt
@@ -0,0 +1,90 @@
+ C2 port support
+ ---------------
+
+(C) Copyright 2007 Rodolfo Giometti <giometti@enneenne.com>
+
+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.
+
+
+
+Overview
+--------
+
+This driver implements the support for Linux of Silicon Labs (Silabs)
+C2 Interface used for in-system programming of micro controllers.
+
+By using this driver you can reprogram the in-system flash without EC2
+or EC3 debug adapter. This solution is also useful in those systems
+where the micro controller is connected via special GPIOs pins.
+
+References
+----------
+
+The C2 Interface main references are at (http://www.silabs.com)
+Silicon Laboratories site], see:
+
+- AN127: FLASH Programming via the C2 Interface at
+http://www.silabs.com/public/documents/tpub_doc/anote/Microcontrollers/Small_Form_Factor/en/an127.pdf, and
+
+- C2 Specification at
+http://www.silabs.com/public/documents/tpub_doc/spec/Microcontrollers/en/C2spec.pdf,
+
+however it implements a two wire serial communication protocol (bit
+banging) designed to enable in-system programming, debugging, and
+boundary-scan testing on low pin-count Silicon Labs devices. Currently
+this code supports only flash programming but extensions are easy to
+add.
+
+Using the driver
+----------------
+
+Once the driver is loaded you can use sysfs support to get C2port's
+info or read/write in-system flash.
+
+# ls /sys/class/c2port/c2port0/
+access flash_block_size flash_erase rev_id
+dev_id flash_blocks_num flash_size subsystem/
+flash_access flash_data reset uevent
+
+Initially the C2port access is disabled since you hardware may have
+such lines multiplexed with other devices so, to get access to the
+C2port, you need the command:
+
+# echo 1 > /sys/class/c2port/c2port0/access
+
+after that you should read the device ID and revision ID of the
+connected micro controller:
+
+# cat /sys/class/c2port/c2port0/dev_id
+8
+# cat /sys/class/c2port/c2port0/rev_id
+1
+
+However, for security reasons, the in-system flash access in not
+enabled yet, to do so you need the command:
+
+# echo 1 > /sys/class/c2port/c2port0/flash_access
+
+After that you can read the whole flash:
+
+# cat /sys/class/c2port/c2port0/flash_data > image
+
+erase it:
+
+# echo 1 > /sys/class/c2port/c2port0/flash_erase
+
+and write it:
+
+# cat image > /sys/class/c2port/c2port0/flash_data
+
+after writing you have to reset the device to execute the new code:
+
+# echo 1 > /sys/class/c2port/c2port0/reset
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index dcac7ca..fee7304 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -498,4 +498,6 @@
This option enables addition debugging code for the SGI GRU driver. If
you are unsure, say N.
+source "drivers/misc/c2port/Kconfig"
+
endif # MISC_DEVICES
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index bb14633..817f7f5 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -32,3 +32,4 @@
obj-$(CONFIG_SGI_XP) += sgi-xp/
obj-$(CONFIG_SGI_GRU) += sgi-gru/
obj-$(CONFIG_HP_ILO) += hpilo.o
+obj-$(CONFIG_C2PORT) += c2port/
diff --git a/drivers/misc/c2port/Kconfig b/drivers/misc/c2port/Kconfig
new file mode 100644
index 0000000..f1bad2b
--- /dev/null
+++ b/drivers/misc/c2port/Kconfig
@@ -0,0 +1,24 @@
+#
+# C2 port devices
+#
+
+menuconfig C2PORT
+ tristate "Silicon Labs C2 port support (EXPERIMENTAL)"
+ depends on EXPERIMENTAL
+ default no
+ help
+ This option enables support for Silicon Labs C2 port used to
+ program Silicon micro controller chips (and other 8051 compatible).
+
+ If your board have no such micro controllers you don't need this
+ interface at all.
+
+ To compile this driver as a module, choose M here: the module will
+ be called c2port_core. Note that you also need a client module
+ usually called c2port-*.
+
+ If you are not sure, say N here.
+
+if C2PORT
+
+endif # C2PORT
diff --git a/drivers/misc/c2port/Makefile b/drivers/misc/c2port/Makefile
new file mode 100644
index 0000000..3c610a2
--- /dev/null
+++ b/drivers/misc/c2port/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_C2PORT) += core.o
diff --git a/drivers/misc/c2port/core.c b/drivers/misc/c2port/core.c
new file mode 100644
index 0000000..976b35d
--- /dev/null
+++ b/drivers/misc/c2port/core.c
@@ -0,0 +1,1002 @@
+/*
+ * Silicon Labs C2 port core Linux support
+ *
+ * Copyright (c) 2007 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (c) 2007 Eurotech S.p.A. <info@eurotech.it>
+ *
+ * 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
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/idr.h>
+
+#include <linux/c2port.h>
+
+#define DRIVER_NAME "c2port"
+#define DRIVER_VERSION "0.51.0"
+
+static DEFINE_SPINLOCK(c2port_idr_lock);
+static DEFINE_IDR(c2port_idr);
+
+/*
+ * Local variables
+ */
+
+static struct class *c2port_class;
+
+/*
+ * C2 registers & commands defines
+ */
+
+/* C2 registers */
+#define C2PORT_DEVICEID 0x00
+#define C2PORT_REVID 0x01
+#define C2PORT_FPCTL 0x02
+#define C2PORT_FPDAT 0xB4
+
+/* C2 interface commands */
+#define C2PORT_GET_VERSION 0x01
+#define C2PORT_DEVICE_ERASE 0x03
+#define C2PORT_BLOCK_READ 0x06
+#define C2PORT_BLOCK_WRITE 0x07
+#define C2PORT_PAGE_ERASE 0x08
+
+/* C2 status return codes */
+#define C2PORT_INVALID_COMMAND 0x00
+#define C2PORT_COMMAND_FAILED 0x02
+#define C2PORT_COMMAND_OK 0x0d
+
+/*
+ * C2 port low level signal managements
+ */
+
+static void c2port_reset(struct c2port_device *dev)
+{
+ struct c2port_ops *ops = dev->ops;
+
+ /* To reset the device we have to keep clock line low for at least
+ * 20us.
+ */
+ local_irq_disable();
+ ops->c2ck_set(dev, 0);
+ udelay(25);
+ ops->c2ck_set(dev, 1);
+ local_irq_enable();
+
+ udelay(1);
+}
+
+static void c2port_strobe_ck(struct c2port_device *dev)
+{
+ struct c2port_ops *ops = dev->ops;
+
+ /* During hi-low-hi transition we disable local IRQs to avoid
+ * interructions since C2 port specification says that it must be
+ * shorter than 5us, otherwise the microcontroller may consider
+ * it as a reset signal!
+ */
+ local_irq_disable();
+ ops->c2ck_set(dev, 0);
+ udelay(1);
+ ops->c2ck_set(dev, 1);
+ local_irq_enable();
+
+ udelay(1);
+}
+
+/*
+ * C2 port basic functions
+ */
+
+static void c2port_write_ar(struct c2port_device *dev, u8 addr)
+{
+ struct c2port_ops *ops = dev->ops;
+ int i;
+
+ /* START field */
+ c2port_strobe_ck(dev);
+
+ /* INS field (11b, LSB first) */
+ ops->c2d_dir(dev, 0);
+ ops->c2d_set(dev, 1);
+ c2port_strobe_ck(dev);
+ ops->c2d_set(dev, 1);
+ c2port_strobe_ck(dev);
+
+ /* ADDRESS field */
+ for (i = 0; i < 8; i++) {
+ ops->c2d_set(dev, addr & 0x01);
+ c2port_strobe_ck(dev);
+
+ addr >>= 1;
+ }
+
+ /* STOP field */
+ ops->c2d_dir(dev, 1);
+ c2port_strobe_ck(dev);
+}
+
+static int c2port_read_ar(struct c2port_device *dev, u8 *addr)
+{
+ struct c2port_ops *ops = dev->ops;
+ int i;
+
+ /* START field */
+ c2port_strobe_ck(dev);
+
+ /* INS field (10b, LSB first) */
+ ops->c2d_dir(dev, 0);
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+ ops->c2d_set(dev, 1);
+ c2port_strobe_ck(dev);
+
+ /* ADDRESS field */
+ ops->c2d_dir(dev, 1);
+ *addr = 0;
+ for (i = 0; i < 8; i++) {
+ *addr >>= 1; /* shift in 8-bit ADDRESS field LSB first */
+
+ c2port_strobe_ck(dev);
+ if (ops->c2d_get(dev))
+ *addr |= 0x80;
+ }
+
+ /* STOP field */
+ c2port_strobe_ck(dev);
+
+ return 0;
+}
+
+static int c2port_write_dr(struct c2port_device *dev, u8 data)
+{
+ struct c2port_ops *ops = dev->ops;
+ int timeout, i;
+
+ /* START field */
+ c2port_strobe_ck(dev);
+
+ /* INS field (01b, LSB first) */
+ ops->c2d_dir(dev, 0);
+ ops->c2d_set(dev, 1);
+ c2port_strobe_ck(dev);
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+
+ /* LENGTH field (00b, LSB first -> 1 byte) */
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+
+ /* DATA field */
+ for (i = 0; i < 8; i++) {
+ ops->c2d_set(dev, data & 0x01);
+ c2port_strobe_ck(dev);
+
+ data >>= 1;
+ }
+
+ /* WAIT field */
+ ops->c2d_dir(dev, 1);
+ timeout = 20;
+ do {
+ c2port_strobe_ck(dev);
+ if (ops->c2d_get(dev))
+ break;
+
+ udelay(1);
+ } while (--timeout > 0);
+ if (timeout == 0)
+ return -EIO;
+
+ /* STOP field */
+ c2port_strobe_ck(dev);
+
+ return 0;
+}
+
+static int c2port_read_dr(struct c2port_device *dev, u8 *data)
+{
+ struct c2port_ops *ops = dev->ops;
+ int timeout, i;
+
+ /* START field */
+ c2port_strobe_ck(dev);
+
+ /* INS field (00b, LSB first) */
+ ops->c2d_dir(dev, 0);
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+
+ /* LENGTH field (00b, LSB first -> 1 byte) */
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+ ops->c2d_set(dev, 0);
+ c2port_strobe_ck(dev);
+
+ /* WAIT field */
+ ops->c2d_dir(dev, 1);
+ timeout = 20;
+ do {
+ c2port_strobe_ck(dev);
+ if (ops->c2d_get(dev))
+ break;
+
+ udelay(1);
+ } while (--timeout > 0);
+ if (timeout == 0)
+ return -EIO;
+
+ /* DATA field */
+ *data = 0;
+ for (i = 0; i < 8; i++) {
+ *data >>= 1; /* shift in 8-bit DATA field LSB first */
+
+ c2port_strobe_ck(dev);
+ if (ops->c2d_get(dev))
+ *data |= 0x80;
+ }
+
+ /* STOP field */
+ c2port_strobe_ck(dev);
+
+ return 0;
+}
+
+static int c2port_poll_in_busy(struct c2port_device *dev)
+{
+ u8 addr;
+ int ret, timeout = 20;
+
+ do {
+ ret = (c2port_read_ar(dev, &addr));
+ if (ret < 0)
+ return -EIO;
+
+ if (!(addr & 0x02))
+ break;
+
+ udelay(1);
+ } while (--timeout > 0);
+ if (timeout == 0)
+ return -EIO;
+
+ return 0;
+}
+
+static int c2port_poll_out_ready(struct c2port_device *dev)
+{
+ u8 addr;
+ int ret, timeout = 10000; /* erase flash needs long time... */
+
+ do {
+ ret = (c2port_read_ar(dev, &addr));
+ if (ret < 0)
+ return -EIO;
+
+ if (addr & 0x01)
+ break;
+
+ udelay(1);
+ } while (--timeout > 0);
+ if (timeout == 0)
+ return -EIO;
+
+ return 0;
+}
+
+/*
+ * sysfs methods
+ */
+
+static ssize_t c2port_show_name(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%s\n", c2dev->name);
+}
+
+static ssize_t c2port_show_flash_blocks_num(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ struct c2port_ops *ops = c2dev->ops;
+
+ return sprintf(buf, "%d\n", ops->blocks_num);
+}
+
+static ssize_t c2port_show_flash_block_size(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ struct c2port_ops *ops = c2dev->ops;
+
+ return sprintf(buf, "%d\n", ops->block_size);
+}
+
+static ssize_t c2port_show_flash_size(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ struct c2port_ops *ops = c2dev->ops;
+
+ return sprintf(buf, "%d\n", ops->blocks_num * ops->block_size);
+}
+
+static ssize_t c2port_show_access(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", c2dev->access);
+}
+
+static ssize_t c2port_store_access(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ struct c2port_ops *ops = c2dev->ops;
+ int status, ret;
+
+ ret = sscanf(buf, "%d", &status);
+ if (ret != 1)
+ return -EINVAL;
+
+ mutex_lock(&c2dev->mutex);
+
+ c2dev->access = !!status;
+
+ /* If access is "on" clock should be HIGH _before_ setting the line
+ * as output and data line should be set as INPUT anyway */
+ if (c2dev->access)
+ ops->c2ck_set(c2dev, 1);
+ ops->access(c2dev, c2dev->access);
+ if (c2dev->access)
+ ops->c2d_dir(c2dev, 1);
+
+ mutex_unlock(&c2dev->mutex);
+
+ return count;
+}
+
+static ssize_t c2port_store_reset(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+
+ /* Check the device access status */
+ if (!c2dev->access)
+ return -EBUSY;
+
+ mutex_lock(&c2dev->mutex);
+
+ c2port_reset(c2dev);
+ c2dev->flash_access = 0;
+
+ mutex_unlock(&c2dev->mutex);
+
+ return count;
+}
+
+static ssize_t __c2port_show_dev_id(struct c2port_device *dev, char *buf)
+{
+ u8 data;
+ int ret;
+
+ /* Select DEVICEID register for C2 data register accesses */
+ c2port_write_ar(dev, C2PORT_DEVICEID);
+
+ /* Read and return the device ID register */
+ ret = c2port_read_dr(dev, &data);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", data);
+}
+
+static ssize_t c2port_show_dev_id(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ ssize_t ret;
+
+ /* Check the device access status */
+ if (!c2dev->access)
+ return -EBUSY;
+
+ mutex_lock(&c2dev->mutex);
+ ret = __c2port_show_dev_id(c2dev, buf);
+ mutex_unlock(&c2dev->mutex);
+
+ if (ret < 0)
+ dev_err(dev, "cannot read from %s\n", c2dev->name);
+
+ return ret;
+}
+
+static ssize_t __c2port_show_rev_id(struct c2port_device *dev, char *buf)
+{
+ u8 data;
+ int ret;
+
+ /* Select REVID register for C2 data register accesses */
+ c2port_write_ar(dev, C2PORT_REVID);
+
+ /* Read and return the revision ID register */
+ ret = c2port_read_dr(dev, &data);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", data);
+}
+
+static ssize_t c2port_show_rev_id(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ ssize_t ret;
+
+ /* Check the device access status */
+ if (!c2dev->access)
+ return -EBUSY;
+
+ mutex_lock(&c2dev->mutex);
+ ret = __c2port_show_rev_id(c2dev, buf);
+ mutex_unlock(&c2dev->mutex);
+
+ if (ret < 0)
+ dev_err(c2dev->dev, "cannot read from %s\n", c2dev->name);
+
+ return ret;
+}
+
+static ssize_t c2port_show_flash_access(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%d\n", c2dev->flash_access);
+}
+
+static ssize_t __c2port_store_flash_access(struct c2port_device *dev,
+ int status)
+{
+ int ret;
+
+ /* Check the device access status */
+ if (!dev->access)
+ return -EBUSY;
+
+ dev->flash_access = !!status;
+
+ /* If flash_access is off we have nothing to do... */
+ if (dev->flash_access == 0)
+ return 0;
+
+ /* Target the C2 flash programming control register for C2 data
+ * register access */
+ c2port_write_ar(dev, C2PORT_FPCTL);
+
+ /* Write the first keycode to enable C2 Flash programming */
+ ret = c2port_write_dr(dev, 0x02);
+ if (ret < 0)
+ return ret;
+
+ /* Write the second keycode to enable C2 Flash programming */
+ ret = c2port_write_dr(dev, 0x01);
+ if (ret < 0)
+ return ret;
+
+ /* Delay for at least 20ms to ensure the target is ready for
+ * C2 flash programming */
+ mdelay(25);
+
+ return 0;
+}
+
+static ssize_t c2port_store_flash_access(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ int status;
+ ssize_t ret;
+
+ ret = sscanf(buf, "%d", &status);
+ if (ret != 1)
+ return -EINVAL;
+
+ mutex_lock(&c2dev->mutex);
+ ret = __c2port_store_flash_access(c2dev, status);
+ mutex_unlock(&c2dev->mutex);
+
+ if (ret < 0) {
+ dev_err(c2dev->dev, "cannot enable %s flash programming\n",
+ c2dev->name);
+ return ret;
+ }
+
+ return count;
+}
+
+static ssize_t __c2port_write_flash_erase(struct c2port_device *dev)
+{
+ u8 status;
+ int ret;
+
+ /* Target the C2 flash programming data register for C2 data register
+ * access.
+ */
+ c2port_write_ar(dev, C2PORT_FPDAT);
+
+ /* Send device erase command */
+ c2port_write_dr(dev, C2PORT_DEVICE_ERASE);
+
+ /* Wait for input acknowledge */
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Should check status before starting FLASH access sequence */
+
+ /* Wait for status information */
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Read flash programming interface status */
+ ret = c2port_read_dr(dev, &status);
+ if (ret < 0)
+ return ret;
+ if (status != C2PORT_COMMAND_OK)
+ return -EBUSY;
+
+ /* Send a three-byte arming sequence to enable the device erase.
+ * If the sequence is not received correctly, the command will be
+ * ignored.
+ * Sequence is: 0xde, 0xad, 0xa5.
+ */
+ c2port_write_dr(dev, 0xde);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+ c2port_write_dr(dev, 0xad);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+ c2port_write_dr(dev, 0xa5);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ return 0;
+}
+
+static ssize_t c2port_store_flash_erase(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct c2port_device *c2dev = dev_get_drvdata(dev);
+ int ret;
+
+ /* Check the device and flash access status */
+ if (!c2dev->access || !c2dev->flash_access)
+ return -EBUSY;
+
+ mutex_lock(&c2dev->mutex);
+ ret = __c2port_write_flash_erase(c2dev);
+ mutex_unlock(&c2dev->mutex);
+
+ if (ret < 0) {
+ dev_err(c2dev->dev, "cannot erase %s flash\n", c2dev->name);
+ return ret;
+ }
+
+ return count;
+}
+
+static ssize_t __c2port_read_flash_data(struct c2port_device *dev,
+ char *buffer, loff_t offset, size_t count)
+{
+ struct c2port_ops *ops = dev->ops;
+ u8 status, nread = 128;
+ int i, ret;
+
+ /* Check for flash end */
+ if (offset >= ops->block_size * ops->blocks_num)
+ return 0;
+
+ if (ops->block_size * ops->blocks_num - offset < nread)
+ nread = ops->block_size * ops->blocks_num - offset;
+ if (count < nread)
+ nread = count;
+ if (nread == 0)
+ return nread;
+
+ /* Target the C2 flash programming data register for C2 data register
+ * access */
+ c2port_write_ar(dev, C2PORT_FPDAT);
+
+ /* Send flash block read command */
+ c2port_write_dr(dev, C2PORT_BLOCK_READ);
+
+ /* Wait for input acknowledge */
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Should check status before starting FLASH access sequence */
+
+ /* Wait for status information */
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Read flash programming interface status */
+ ret = c2port_read_dr(dev, &status);
+ if (ret < 0)
+ return ret;
+ if (status != C2PORT_COMMAND_OK)
+ return -EBUSY;
+
+ /* Send address high byte */
+ c2port_write_dr(dev, offset >> 8);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Send address low byte */
+ c2port_write_dr(dev, offset & 0x00ff);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Send address block size */
+ c2port_write_dr(dev, nread);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Should check status before reading FLASH block */
+
+ /* Wait for status information */
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Read flash programming interface status */
+ ret = c2port_read_dr(dev, &status);
+ if (ret < 0)
+ return ret;
+ if (status != C2PORT_COMMAND_OK)
+ return -EBUSY;
+
+ /* Read flash block */
+ for (i = 0; i < nread; i++) {
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ ret = c2port_read_dr(dev, buffer+i);
+ if (ret < 0)
+ return ret;
+ }
+
+ return nread;
+}
+
+static ssize_t c2port_read_flash_data(struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buffer, loff_t offset, size_t count)
+{
+ struct c2port_device *c2dev =
+ dev_get_drvdata(container_of(kobj,
+ struct device, kobj));
+ ssize_t ret;
+
+ /* Check the device and flash access status */
+ if (!c2dev->access || !c2dev->flash_access)
+ return -EBUSY;
+
+ mutex_lock(&c2dev->mutex);
+ ret = __c2port_read_flash_data(c2dev, buffer, offset, count);
+ mutex_unlock(&c2dev->mutex);
+
+ if (ret < 0)
+ dev_err(c2dev->dev, "cannot read %s flash\n", c2dev->name);
+
+ return ret;
+}
+
+static ssize_t __c2port_write_flash_data(struct c2port_device *dev,
+ char *buffer, loff_t offset, size_t count)
+{
+ struct c2port_ops *ops = dev->ops;
+ u8 status, nwrite = 128;
+ int i, ret;
+
+ if (nwrite > count)
+ nwrite = count;
+ if (ops->block_size * ops->blocks_num - offset < nwrite)
+ nwrite = ops->block_size * ops->blocks_num - offset;
+
+ /* Check for flash end */
+ if (offset >= ops->block_size * ops->blocks_num)
+ return -EINVAL;
+
+ /* Target the C2 flash programming data register for C2 data register
+ * access */
+ c2port_write_ar(dev, C2PORT_FPDAT);
+
+ /* Send flash block write command */
+ c2port_write_dr(dev, C2PORT_BLOCK_WRITE);
+
+ /* Wait for input acknowledge */
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Should check status before starting FLASH access sequence */
+
+ /* Wait for status information */
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Read flash programming interface status */
+ ret = c2port_read_dr(dev, &status);
+ if (ret < 0)
+ return ret;
+ if (status != C2PORT_COMMAND_OK)
+ return -EBUSY;
+
+ /* Send address high byte */
+ c2port_write_dr(dev, offset >> 8);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Send address low byte */
+ c2port_write_dr(dev, offset & 0x00ff);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Send address block size */
+ c2port_write_dr(dev, nwrite);
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Should check status before writing FLASH block */
+
+ /* Wait for status information */
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ /* Read flash programming interface status */
+ ret = c2port_read_dr(dev, &status);
+ if (ret < 0)
+ return ret;
+ if (status != C2PORT_COMMAND_OK)
+ return -EBUSY;
+
+ /* Write flash block */
+ for (i = 0; i < nwrite; i++) {
+ ret = c2port_write_dr(dev, *(buffer+i));
+ if (ret < 0)
+ return ret;
+
+ ret = c2port_poll_in_busy(dev);
+ if (ret < 0)
+ return ret;
+
+ }
+
+ /* Wait for last flash write to complete */
+ ret = c2port_poll_out_ready(dev);
+ if (ret < 0)
+ return ret;
+
+ return nwrite;
+}
+
+static ssize_t c2port_write_flash_data(struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buffer, loff_t offset, size_t count)
+{
+ struct c2port_device *c2dev =
+ dev_get_drvdata(container_of(kobj,
+ struct device, kobj));
+ int ret;
+
+ /* Check the device access status */
+ if (!c2dev->access || !c2dev->flash_access)
+ return -EBUSY;
+
+ mutex_lock(&c2dev->mutex);
+ ret = __c2port_write_flash_data(c2dev, buffer, offset, count);
+ mutex_unlock(&c2dev->mutex);
+
+ if (ret < 0)
+ dev_err(c2dev->dev, "cannot write %s flash\n", c2dev->name);
+
+ return ret;
+}
+
+/*
+ * Class attributes
+ */
+
+static struct device_attribute c2port_attrs[] = {
+ __ATTR(name, 0444, c2port_show_name, NULL),
+ __ATTR(flash_blocks_num, 0444, c2port_show_flash_blocks_num, NULL),
+ __ATTR(flash_block_size, 0444, c2port_show_flash_block_size, NULL),
+ __ATTR(flash_size, 0444, c2port_show_flash_size, NULL),
+ __ATTR(access, 0644, c2port_show_access, c2port_store_access),
+ __ATTR(reset, 0200, NULL, c2port_store_reset),
+ __ATTR(dev_id, 0444, c2port_show_dev_id, NULL),
+ __ATTR(rev_id, 0444, c2port_show_rev_id, NULL),
+
+ __ATTR(flash_access, 0644, c2port_show_flash_access,
+ c2port_store_flash_access),
+ __ATTR(flash_erase, 0200, NULL, c2port_store_flash_erase),
+ __ATTR_NULL,
+};
+
+static struct bin_attribute c2port_bin_attrs = {
+ .attr = {
+ .name = "flash_data",
+ .mode = 0644
+ },
+ .read = c2port_read_flash_data,
+ .write = c2port_write_flash_data,
+ /* .size is computed at run-time */
+};
+
+/*
+ * Exported functions
+ */
+
+struct c2port_device *c2port_device_register(char *name,
+ struct c2port_ops *ops, void *devdata)
+{
+ struct c2port_device *c2dev;
+ int id, ret;
+
+ if (unlikely(!ops) || unlikely(!ops->access) || \
+ unlikely(!ops->c2d_dir) || unlikely(!ops->c2ck_set) || \
+ unlikely(!ops->c2d_get) || unlikely(!ops->c2d_set))
+ return ERR_PTR(-EINVAL);
+
+ c2dev = kmalloc(sizeof(struct c2port_device), GFP_KERNEL);
+ if (unlikely(!c2dev))
+ return ERR_PTR(-ENOMEM);
+
+ ret = idr_pre_get(&c2port_idr, GFP_KERNEL);
+ if (!ret) {
+ ret = -ENOMEM;
+ goto error_idr_get_new;
+ }
+
+ spin_lock_irq(&c2port_idr_lock);
+ ret = idr_get_new(&c2port_idr, c2dev, &id);
+ spin_unlock_irq(&c2port_idr_lock);
+
+ if (ret < 0)
+ goto error_idr_get_new;
+ c2dev->id = id;
+
+ c2dev->dev = device_create(c2port_class, NULL, 0, c2dev,
+ "c2port%d", id);
+ if (unlikely(!c2dev->dev)) {
+ ret = -ENOMEM;
+ goto error_device_create;
+ }
+ dev_set_drvdata(c2dev->dev, c2dev);
+
+ strncpy(c2dev->name, name, C2PORT_NAME_LEN);
+ c2dev->ops = ops;
+ mutex_init(&c2dev->mutex);
+
+ /* Create binary file */
+ c2port_bin_attrs.size = ops->blocks_num * ops->block_size;
+ ret = device_create_bin_file(c2dev->dev, &c2port_bin_attrs);
+ if (unlikely(ret))
+ goto error_device_create_bin_file;
+
+ /* By default C2 port access is off */
+ c2dev->access = c2dev->flash_access = 0;
+ ops->access(c2dev, 0);
+
+ dev_info(c2dev->dev, "C2 port %s added\n", name);
+ dev_info(c2dev->dev, "%s flash has %d blocks x %d bytes "
+ "(%d bytes total)\n",
+ name, ops->blocks_num, ops->block_size,
+ ops->blocks_num * ops->block_size);
+
+ return c2dev;
+
+error_device_create_bin_file:
+ device_destroy(c2port_class, 0);
+
+error_device_create:
+ spin_lock_irq(&c2port_idr_lock);
+ idr_remove(&c2port_idr, id);
+ spin_unlock_irq(&c2port_idr_lock);
+
+error_idr_get_new:
+ kfree(c2dev);
+
+ return ERR_PTR(ret);
+}
+EXPORT_SYMBOL(c2port_device_register);
+
+void c2port_device_unregister(struct c2port_device *c2dev)
+{
+ if (!c2dev)
+ return;
+
+ dev_info(c2dev->dev, "C2 port %s removed\n", c2dev->name);
+
+ device_remove_bin_file(c2dev->dev, &c2port_bin_attrs);
+ spin_lock_irq(&c2port_idr_lock);
+ idr_remove(&c2port_idr, c2dev->id);
+ spin_unlock_irq(&c2port_idr_lock);
+
+ device_destroy(c2port_class, c2dev->id);
+
+ kfree(c2dev);
+}
+EXPORT_SYMBOL(c2port_device_unregister);
+
+/*
+ * Module stuff
+ */
+
+static int __init c2port_init(void)
+{
+ printk(KERN_INFO "Silicon Labs C2 port support v. " DRIVER_VERSION
+ " - (C) 2007 Rodolfo Giometti\n");
+
+ c2port_class = class_create(THIS_MODULE, "c2port");
+ if (!c2port_class) {
+ printk(KERN_ERR "c2port: failed to allocate class\n");
+ return -ENOMEM;
+ }
+ c2port_class->dev_attrs = c2port_attrs;
+
+ return 0;
+}
+
+static void __exit c2port_exit(void)
+{
+ class_destroy(c2port_class);
+}
+
+module_init(c2port_init);
+module_exit(c2port_exit);
+
+MODULE_AUTHOR("Rodolfo Giometti <giometti@linux.it>");
+MODULE_DESCRIPTION("Silicon Labs C2 port support v. " DRIVER_VERSION);
+MODULE_LICENSE("GPL");
diff --git a/include/linux/c2port.h b/include/linux/c2port.h
new file mode 100644
index 0000000..7b5a238
--- /dev/null
+++ b/include/linux/c2port.h
@@ -0,0 +1,65 @@
+/*
+ * Silicon Labs C2 port Linux support
+ *
+ * Copyright (c) 2007 Rodolfo Giometti <giometti@linux.it>
+ * Copyright (c) 2007 Eurotech S.p.A. <info@eurotech.it>
+ *
+ * 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
+ */
+
+#include <linux/device.h>
+
+#define C2PORT_NAME_LEN 32
+
+/*
+ * C2 port basic structs
+ */
+
+/* Main struct */
+struct c2port_ops;
+struct c2port_device {
+ unsigned int access:1;
+ unsigned int flash_access:1;
+
+ int id;
+ char name[C2PORT_NAME_LEN];
+ struct c2port_ops *ops;
+ struct mutex mutex; /* prevent races during read/write */
+
+ struct device *dev;
+
+ void *private_data;
+};
+
+/* Basic operations */
+struct c2port_ops {
+ /* Flash layout */
+ unsigned short block_size; /* flash block size in bytes */
+ unsigned short blocks_num; /* flash blocks number */
+
+ /* Enable or disable the access to C2 port */
+ void (*access)(struct c2port_device *dev, int status);
+
+ /* Set C2D data line as input/output */
+ void (*c2d_dir)(struct c2port_device *dev, int dir);
+
+ /* Read/write C2D data line */
+ int (*c2d_get)(struct c2port_device *dev);
+ void (*c2d_set)(struct c2port_device *dev, int status);
+
+ /* Write C2CK clock line */
+ void (*c2ck_set)(struct c2port_device *dev, int status);
+};
+
+/*
+ * Exported functions
+ */
+
+#define to_class_dev(obj) container_of((obj), struct class_device, kobj)
+#define to_c2port_device(obj) container_of((obj), struct c2port_device, class)
+
+extern struct c2port_device *c2port_device_register(char *name,
+ struct c2port_ops *ops, void *devdata);
+extern void c2port_device_unregister(struct c2port_device *dev);