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authorLinus Torvalds <torvalds@linux-foundation.org>2011-05-23 12:23:20 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-05-23 12:23:20 -0700
commit99dff5856220a02b8711f2e8746413ea6e53ccf6 (patch)
treed8bae7ccdf8f7ad5221b053bb74a6220df996b3a /drivers/misc/pti.c
parentbb74e8ca352eecefdc5c1a9ebab01f18aa2f6f3c (diff)
parentd9a0fbfd7bc5d2c42f0fa9bcbdab62c4942d0388 (diff)
downloadlinux-99dff5856220a02b8711f2e8746413ea6e53ccf6.tar.bz2
Merge branch 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6
* 'tty-next' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty-2.6: (48 commits) serial: 8250_pci: add support for Cronyx Omega PCI multiserial board. tty/serial: Fix break handling for PORT_TEGRA tty/serial: Add explicit PORT_TEGRA type n_tracerouter and n_tracesink ldisc additions. Intel PTI implementaiton of MIPI 1149.7. Kernel documentation for the PTI feature. export kernel call get_task_comm(). tty: Remove to support serial for S5P6442 pch_phub: Support new device ML7223 8250_pci: Add support for the Digi/IBM PCIe 2-port Adapter ASoC: Update cx20442 for TTY API change pch_uart: Support new device ML7223 IOH parport: Use request_muxed_region for IT87 probe and lock tty/serial: add support for Xilinx PS UART n_gsm: Use print_hex_dump_bytes drivers/tty/moxa.c: Put correct tty value TTY: tty_io, annotate locking functions TTY: serial_core, remove superfluous set_task_state TTY: serial_core, remove invalid test Char: moxa, fix locking in moxa_write ... Fix up trivial conflicts in drivers/bluetooth/hci_ldisc.c and drivers/tty/serial/Makefile. I did the hci_ldisc thing as an evil merge, cleaning things up.
Diffstat (limited to 'drivers/misc/pti.c')
-rw-r--r--drivers/misc/pti.c980
1 files changed, 980 insertions, 0 deletions
diff --git a/drivers/misc/pti.c b/drivers/misc/pti.c
new file mode 100644
index 000000000000..bb6f9255c17c
--- /dev/null
+++ b/drivers/misc/pti.c
@@ -0,0 +1,980 @@
+/*
+ * pti.c - PTI driver for cJTAG data extration
+ *
+ * Copyright (C) Intel 2010
+ *
+ * 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.
+ *
+ * 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.
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * The PTI (Parallel Trace Interface) driver directs trace data routed from
+ * various parts in the system out through the Intel Penwell PTI port and
+ * out of the mobile device for analysis with a debugging tool
+ * (Lauterbach, Fido). This is part of a solution for the MIPI P1149.7,
+ * compact JTAG, standard.
+ */
+
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/console.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/pci.h>
+#include <linux/mutex.h>
+#include <linux/miscdevice.h>
+#include <linux/pti.h>
+
+#define DRIVERNAME "pti"
+#define PCINAME "pciPTI"
+#define TTYNAME "ttyPTI"
+#define CHARNAME "pti"
+#define PTITTY_MINOR_START 0
+#define PTITTY_MINOR_NUM 2
+#define MAX_APP_IDS 16 /* 128 channel ids / u8 bit size */
+#define MAX_OS_IDS 16 /* 128 channel ids / u8 bit size */
+#define MAX_MODEM_IDS 16 /* 128 channel ids / u8 bit size */
+#define MODEM_BASE_ID 71 /* modem master ID address */
+#define CONTROL_ID 72 /* control master ID address */
+#define CONSOLE_ID 73 /* console master ID address */
+#define OS_BASE_ID 74 /* base OS master ID address */
+#define APP_BASE_ID 80 /* base App master ID address */
+#define CONTROL_FRAME_LEN 32 /* PTI control frame maximum size */
+#define USER_COPY_SIZE 8192 /* 8Kb buffer for user space copy */
+#define APERTURE_14 0x3800000 /* offset to first OS write addr */
+#define APERTURE_LEN 0x400000 /* address length */
+
+struct pti_tty {
+ struct pti_masterchannel *mc;
+};
+
+struct pti_dev {
+ struct tty_port port;
+ unsigned long pti_addr;
+ unsigned long aperture_base;
+ void __iomem *pti_ioaddr;
+ u8 ia_app[MAX_APP_IDS];
+ u8 ia_os[MAX_OS_IDS];
+ u8 ia_modem[MAX_MODEM_IDS];
+};
+
+/*
+ * This protects access to ia_app, ia_os, and ia_modem,
+ * which keeps track of channels allocated in
+ * an aperture write id.
+ */
+static DEFINE_MUTEX(alloclock);
+
+static struct pci_device_id pci_ids[] __devinitconst = {
+ {PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x82B)},
+ {0}
+};
+
+static struct tty_driver *pti_tty_driver;
+static struct pti_dev *drv_data;
+
+static unsigned int pti_console_channel;
+static unsigned int pti_control_channel;
+
+/**
+ * pti_write_to_aperture()- The private write function to PTI HW.
+ *
+ * @mc: The 'aperture'. It's part of a write address that holds
+ * a master and channel ID.
+ * @buf: Data being written to the HW that will ultimately be seen
+ * in a debugging tool (Fido, Lauterbach).
+ * @len: Size of buffer.
+ *
+ * Since each aperture is specified by a unique
+ * master/channel ID, no two processes will be writing
+ * to the same aperture at the same time so no lock is required. The
+ * PTI-Output agent will send these out in the order that they arrived, and
+ * thus, it will intermix these messages. The debug tool can then later
+ * regroup the appropriate message segments together reconstituting each
+ * message.
+ */
+static void pti_write_to_aperture(struct pti_masterchannel *mc,
+ u8 *buf,
+ int len)
+{
+ int dwordcnt;
+ int final;
+ int i;
+ u32 ptiword;
+ u32 __iomem *aperture;
+ u8 *p = buf;
+
+ /*
+ * calculate the aperture offset from the base using the master and
+ * channel id's.
+ */
+ aperture = drv_data->pti_ioaddr + (mc->master << 15)
+ + (mc->channel << 8);
+
+ dwordcnt = len >> 2;
+ final = len - (dwordcnt << 2); /* final = trailing bytes */
+ if (final == 0 && dwordcnt != 0) { /* always need a final dword */
+ final += 4;
+ dwordcnt--;
+ }
+
+ for (i = 0; i < dwordcnt; i++) {
+ ptiword = be32_to_cpu(*(u32 *)p);
+ p += 4;
+ iowrite32(ptiword, aperture);
+ }
+
+ aperture += PTI_LASTDWORD_DTS; /* adding DTS signals that is EOM */
+
+ ptiword = 0;
+ for (i = 0; i < final; i++)
+ ptiword |= *p++ << (24-(8*i));
+
+ iowrite32(ptiword, aperture);
+ return;
+}
+
+/**
+ * pti_control_frame_built_and_sent()- control frame build and send function.
+ *
+ * @mc: The master / channel structure on which the function
+ * built a control frame.
+ *
+ * To be able to post process the PTI contents on host side, a control frame
+ * is added before sending any PTI content. So the host side knows on
+ * each PTI frame the name of the thread using a dedicated master / channel.
+ * The thread name is retrieved from the 'current' global variable.
+ * This function builds this frame and sends it to a master ID CONTROL_ID.
+ * The overhead is only 32 bytes since the driver only writes to HW
+ * in 32 byte chunks.
+ */
+
+static void pti_control_frame_built_and_sent(struct pti_masterchannel *mc)
+{
+ struct pti_masterchannel mccontrol = {.master = CONTROL_ID,
+ .channel = 0};
+ const char *control_format = "%3d %3d %s";
+ u8 control_frame[CONTROL_FRAME_LEN];
+
+ /*
+ * Since we access the comm member in current's task_struct,
+ * we only need to be as large as what 'comm' in that
+ * structure is.
+ */
+ char comm[TASK_COMM_LEN];
+
+ if (!in_interrupt())
+ get_task_comm(comm, current);
+ else
+ strncpy(comm, "Interrupt", TASK_COMM_LEN);
+
+ /* Absolutely ensure our buffer is zero terminated. */
+ comm[TASK_COMM_LEN-1] = 0;
+
+ mccontrol.channel = pti_control_channel;
+ pti_control_channel = (pti_control_channel + 1) & 0x7f;
+
+ snprintf(control_frame, CONTROL_FRAME_LEN, control_format, mc->master,
+ mc->channel, comm);
+ pti_write_to_aperture(&mccontrol, control_frame, strlen(control_frame));
+}
+
+/**
+ * pti_write_full_frame_to_aperture()- high level function to
+ * write to PTI.
+ *
+ * @mc: The 'aperture'. It's part of a write address that holds
+ * a master and channel ID.
+ * @buf: Data being written to the HW that will ultimately be seen
+ * in a debugging tool (Fido, Lauterbach).
+ * @len: Size of buffer.
+ *
+ * All threads sending data (either console, user space application, ...)
+ * are calling the high level function to write to PTI meaning that it is
+ * possible to add a control frame before sending the content.
+ */
+static void pti_write_full_frame_to_aperture(struct pti_masterchannel *mc,
+ const unsigned char *buf,
+ int len)
+{
+ pti_control_frame_built_and_sent(mc);
+ pti_write_to_aperture(mc, (u8 *)buf, len);
+}
+
+/**
+ * get_id()- Allocate a master and channel ID.
+ *
+ * @id_array: an array of bits representing what channel
+ * id's are allocated for writing.
+ * @max_ids: The max amount of available write IDs to use.
+ * @base_id: The starting SW channel ID, based on the Intel
+ * PTI arch.
+ *
+ * Returns:
+ * pti_masterchannel struct with master, channel ID address
+ * 0 for error
+ *
+ * Each bit in the arrays ia_app and ia_os correspond to a master and
+ * channel id. The bit is one if the id is taken and 0 if free. For
+ * every master there are 128 channel id's.
+ */
+static struct pti_masterchannel *get_id(u8 *id_array, int max_ids, int base_id)
+{
+ struct pti_masterchannel *mc;
+ int i, j, mask;
+
+ mc = kmalloc(sizeof(struct pti_masterchannel), GFP_KERNEL);
+ if (mc == NULL)
+ return NULL;
+
+ /* look for a byte with a free bit */
+ for (i = 0; i < max_ids; i++)
+ if (id_array[i] != 0xff)
+ break;
+ if (i == max_ids) {
+ kfree(mc);
+ return NULL;
+ }
+ /* find the bit in the 128 possible channel opportunities */
+ mask = 0x80;
+ for (j = 0; j < 8; j++) {
+ if ((id_array[i] & mask) == 0)
+ break;
+ mask >>= 1;
+ }
+
+ /* grab it */
+ id_array[i] |= mask;
+ mc->master = base_id;
+ mc->channel = ((i & 0xf)<<3) + j;
+ /* write new master Id / channel Id allocation to channel control */
+ pti_control_frame_built_and_sent(mc);
+ return mc;
+}
+
+/*
+ * The following three functions:
+ * pti_request_mastercahannel(), mipi_release_masterchannel()
+ * and pti_writedata() are an API for other kernel drivers to
+ * access PTI.
+ */
+
+/**
+ * pti_request_masterchannel()- Kernel API function used to allocate
+ * a master, channel ID address
+ * to write to PTI HW.
+ *
+ * @type: 0- request Application master, channel aperture ID write address.
+ * 1- request OS master, channel aperture ID write
+ * address.
+ * 2- request Modem master, channel aperture ID
+ * write address.
+ * Other values, error.
+ *
+ * Returns:
+ * pti_masterchannel struct
+ * 0 for error
+ */
+struct pti_masterchannel *pti_request_masterchannel(u8 type)
+{
+ struct pti_masterchannel *mc;
+
+ mutex_lock(&alloclock);
+
+ switch (type) {
+
+ case 0:
+ mc = get_id(drv_data->ia_app, MAX_APP_IDS, APP_BASE_ID);
+ break;
+
+ case 1:
+ mc = get_id(drv_data->ia_os, MAX_OS_IDS, OS_BASE_ID);
+ break;
+
+ case 2:
+ mc = get_id(drv_data->ia_modem, MAX_MODEM_IDS, MODEM_BASE_ID);
+ break;
+ default:
+ mc = NULL;
+ }
+
+ mutex_unlock(&alloclock);
+ return mc;
+}
+EXPORT_SYMBOL_GPL(pti_request_masterchannel);
+
+/**
+ * pti_release_masterchannel()- Kernel API function used to release
+ * a master, channel ID address
+ * used to write to PTI HW.
+ *
+ * @mc: master, channel apeture ID address to be released.
+ */
+void pti_release_masterchannel(struct pti_masterchannel *mc)
+{
+ u8 master, channel, i;
+
+ mutex_lock(&alloclock);
+
+ if (mc) {
+ master = mc->master;
+ channel = mc->channel;
+
+ if (master == APP_BASE_ID) {
+ i = channel >> 3;
+ drv_data->ia_app[i] &= ~(0x80>>(channel & 0x7));
+ } else if (master == OS_BASE_ID) {
+ i = channel >> 3;
+ drv_data->ia_os[i] &= ~(0x80>>(channel & 0x7));
+ } else {
+ i = channel >> 3;
+ drv_data->ia_modem[i] &= ~(0x80>>(channel & 0x7));
+ }
+
+ kfree(mc);
+ }
+
+ mutex_unlock(&alloclock);
+}
+EXPORT_SYMBOL_GPL(pti_release_masterchannel);
+
+/**
+ * pti_writedata()- Kernel API function used to write trace
+ * debugging data to PTI HW.
+ *
+ * @mc: Master, channel aperture ID address to write to.
+ * Null value will return with no write occurring.
+ * @buf: Trace debuging data to write to the PTI HW.
+ * Null value will return with no write occurring.
+ * @count: Size of buf. Value of 0 or a negative number will
+ * return with no write occuring.
+ */
+void pti_writedata(struct pti_masterchannel *mc, u8 *buf, int count)
+{
+ /*
+ * since this function is exported, this is treated like an
+ * API function, thus, all parameters should
+ * be checked for validity.
+ */
+ if ((mc != NULL) && (buf != NULL) && (count > 0))
+ pti_write_to_aperture(mc, buf, count);
+ return;
+}
+EXPORT_SYMBOL_GPL(pti_writedata);
+
+/**
+ * pti_pci_remove()- Driver exit method to remove PTI from
+ * PCI bus.
+ * @pdev: variable containing pci info of PTI.
+ */
+static void __devexit pti_pci_remove(struct pci_dev *pdev)
+{
+ struct pti_dev *drv_data;
+
+ drv_data = pci_get_drvdata(pdev);
+ if (drv_data != NULL) {
+ pci_iounmap(pdev, drv_data->pti_ioaddr);
+ pci_set_drvdata(pdev, NULL);
+ kfree(drv_data);
+ pci_release_region(pdev, 1);
+ pci_disable_device(pdev);
+ }
+}
+
+/*
+ * for the tty_driver_*() basic function descriptions, see tty_driver.h.
+ * Specific header comments made for PTI-related specifics.
+ */
+
+/**
+ * pti_tty_driver_open()- Open an Application master, channel aperture
+ * ID to the PTI device via tty device.
+ *
+ * @tty: tty interface.
+ * @filp: filp interface pased to tty_port_open() call.
+ *
+ * Returns:
+ * int, 0 for success
+ * otherwise, fail value
+ *
+ * The main purpose of using the tty device interface is for
+ * each tty port to have a unique PTI write aperture. In an
+ * example use case, ttyPTI0 gets syslogd and an APP aperture
+ * ID and ttyPTI1 is where the n_tracesink ldisc hooks to route
+ * modem messages into PTI. Modem trace data does not have to
+ * go to ttyPTI1, but ttyPTI0 and ttyPTI1 do need to be distinct
+ * master IDs. These messages go through the PTI HW and out of
+ * the handheld platform and to the Fido/Lauterbach device.
+ */
+static int pti_tty_driver_open(struct tty_struct *tty, struct file *filp)
+{
+ /*
+ * we actually want to allocate a new channel per open, per
+ * system arch. HW gives more than plenty channels for a single
+ * system task to have its own channel to write trace data. This
+ * also removes a locking requirement for the actual write
+ * procedure.
+ */
+ return tty_port_open(&drv_data->port, tty, filp);
+}
+
+/**
+ * pti_tty_driver_close()- close tty device and release Application
+ * master, channel aperture ID to the PTI device via tty device.
+ *
+ * @tty: tty interface.
+ * @filp: filp interface pased to tty_port_close() call.
+ *
+ * The main purpose of using the tty device interface is to route
+ * syslog daemon messages to the PTI HW and out of the handheld platform
+ * and to the Fido/Lauterbach device.
+ */
+static void pti_tty_driver_close(struct tty_struct *tty, struct file *filp)
+{
+ tty_port_close(&drv_data->port, tty, filp);
+}
+
+/**
+ * pti_tty_intstall()- Used to set up specific master-channels
+ * to tty ports for organizational purposes when
+ * tracing viewed from debuging tools.
+ *
+ * @driver: tty driver information.
+ * @tty: tty struct containing pti information.
+ *
+ * Returns:
+ * 0 for success
+ * otherwise, error
+ */
+static int pti_tty_install(struct tty_driver *driver, struct tty_struct *tty)
+{
+ int idx = tty->index;
+ struct pti_tty *pti_tty_data;
+ int ret = tty_init_termios(tty);
+
+ if (ret == 0) {
+ tty_driver_kref_get(driver);
+ tty->count++;
+ driver->ttys[idx] = tty;
+
+ pti_tty_data = kmalloc(sizeof(struct pti_tty), GFP_KERNEL);
+ if (pti_tty_data == NULL)
+ return -ENOMEM;
+
+ if (idx == PTITTY_MINOR_START)
+ pti_tty_data->mc = pti_request_masterchannel(0);
+ else
+ pti_tty_data->mc = pti_request_masterchannel(2);
+
+ if (pti_tty_data->mc == NULL)
+ return -ENXIO;
+ tty->driver_data = pti_tty_data;
+ }
+
+ return ret;
+}
+
+/**
+ * pti_tty_cleanup()- Used to de-allocate master-channel resources
+ * tied to tty's of this driver.
+ *
+ * @tty: tty struct containing pti information.
+ */
+static void pti_tty_cleanup(struct tty_struct *tty)
+{
+ struct pti_tty *pti_tty_data = tty->driver_data;
+ if (pti_tty_data == NULL)
+ return;
+ pti_release_masterchannel(pti_tty_data->mc);
+ kfree(tty->driver_data);
+ tty->driver_data = NULL;
+}
+
+/**
+ * pti_tty_driver_write()- Write trace debugging data through the char
+ * interface to the PTI HW. Part of the misc device implementation.
+ *
+ * @filp: Contains private data which is used to obtain
+ * master, channel write ID.
+ * @data: trace data to be written.
+ * @len: # of byte to write.
+ *
+ * Returns:
+ * int, # of bytes written
+ * otherwise, error
+ */
+static int pti_tty_driver_write(struct tty_struct *tty,
+ const unsigned char *buf, int len)
+{
+ struct pti_tty *pti_tty_data = tty->driver_data;
+ if ((pti_tty_data != NULL) && (pti_tty_data->mc != NULL)) {
+ pti_write_to_aperture(pti_tty_data->mc, (u8 *)buf, len);
+ return len;
+ }
+ /*
+ * we can't write to the pti hardware if the private driver_data
+ * and the mc address is not there.
+ */
+ else
+ return -EFAULT;
+}
+
+/**
+ * pti_tty_write_room()- Always returns 2048.
+ *
+ * @tty: contains tty info of the pti driver.
+ */
+static int pti_tty_write_room(struct tty_struct *tty)
+{
+ return 2048;
+}
+
+/**
+ * pti_char_open()- Open an Application master, channel aperture
+ * ID to the PTI device. Part of the misc device implementation.
+ *
+ * @inode: not used.
+ * @filp: Output- will have a masterchannel struct set containing
+ * the allocated application PTI aperture write address.
+ *
+ * Returns:
+ * int, 0 for success
+ * otherwise, a fail value
+ */
+static int pti_char_open(struct inode *inode, struct file *filp)
+{
+ struct pti_masterchannel *mc;
+
+ /*
+ * We really do want to fail immediately if
+ * pti_request_masterchannel() fails,
+ * before assigning the value to filp->private_data.
+ * Slightly easier to debug if this driver needs debugging.
+ */
+ mc = pti_request_masterchannel(0);
+ if (mc == NULL)
+ return -ENOMEM;
+ filp->private_data = mc;
+ return 0;
+}
+
+/**
+ * pti_char_release()- Close a char channel to the PTI device. Part
+ * of the misc device implementation.
+ *
+ * @inode: Not used in this implementaiton.
+ * @filp: Contains private_data that contains the master, channel
+ * ID to be released by the PTI device.
+ *
+ * Returns:
+ * always 0
+ */
+static int pti_char_release(struct inode *inode, struct file *filp)
+{
+ pti_release_masterchannel(filp->private_data);
+ kfree(filp->private_data);
+ return 0;
+}
+
+/**
+ * pti_char_write()- Write trace debugging data through the char
+ * interface to the PTI HW. Part of the misc device implementation.
+ *
+ * @filp: Contains private data which is used to obtain
+ * master, channel write ID.
+ * @data: trace data to be written.
+ * @len: # of byte to write.
+ * @ppose: Not used in this function implementation.
+ *
+ * Returns:
+ * int, # of bytes written
+ * otherwise, error value
+ *
+ * Notes: From side discussions with Alan Cox and experimenting
+ * with PTI debug HW like Nokia's Fido box and Lauterbach
+ * devices, 8192 byte write buffer used by USER_COPY_SIZE was
+ * deemed an appropriate size for this type of usage with
+ * debugging HW.
+ */
+static ssize_t pti_char_write(struct file *filp, const char __user *data,
+ size_t len, loff_t *ppose)
+{
+ struct pti_masterchannel *mc;
+ void *kbuf;
+ const char __user *tmp;
+ size_t size = USER_COPY_SIZE;
+ size_t n = 0;
+
+ tmp = data;
+ mc = filp->private_data;
+
+ kbuf = kmalloc(size, GFP_KERNEL);
+ if (kbuf == NULL) {
+ pr_err("%s(%d): buf allocation failed\n",
+ __func__, __LINE__);
+ return -ENOMEM;
+ }
+
+ do {
+ if (len - n > USER_COPY_SIZE)
+ size = USER_COPY_SIZE;
+ else
+ size = len - n;
+
+ if (copy_from_user(kbuf, tmp, size)) {
+ kfree(kbuf);
+ return n ? n : -EFAULT;
+ }
+
+ pti_write_to_aperture(mc, kbuf, size);
+ n += size;
+ tmp += size;
+
+ } while (len > n);
+
+ kfree(kbuf);
+ return len;
+}
+
+static const struct tty_operations pti_tty_driver_ops = {
+ .open = pti_tty_driver_open,
+ .close = pti_tty_driver_close,
+ .write = pti_tty_driver_write,
+ .write_room = pti_tty_write_room,
+ .install = pti_tty_install,
+ .cleanup = pti_tty_cleanup
+};
+
+static const struct file_operations pti_char_driver_ops = {
+ .owner = THIS_MODULE,
+ .write = pti_char_write,
+ .open = pti_char_open,
+ .release = pti_char_release,
+};
+
+static struct miscdevice pti_char_driver = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = CHARNAME,
+ .fops = &pti_char_driver_ops
+};
+
+/**
+ * pti_console_write()- Write to the console that has been acquired.
+ *
+ * @c: Not used in this implementaiton.
+ * @buf: Data to be written.
+ * @len: Length of buf.
+ */
+static void pti_console_write(struct console *c, const char *buf, unsigned len)
+{
+ static struct pti_masterchannel mc = {.master = CONSOLE_ID,
+ .channel = 0};
+
+ mc.channel = pti_console_channel;
+ pti_console_channel = (pti_console_channel + 1) & 0x7f;
+
+ pti_write_full_frame_to_aperture(&mc, buf, len);
+}
+
+/**
+ * pti_console_device()- Return the driver tty structure and set the
+ * associated index implementation.
+ *
+ * @c: Console device of the driver.
+ * @index: index associated with c.
+ *
+ * Returns:
+ * always value of pti_tty_driver structure when this function
+ * is called.
+ */
+static struct tty_driver *pti_console_device(struct console *c, int *index)
+{
+ *index = c->index;
+ return pti_tty_driver;
+}
+
+/**
+ * pti_console_setup()- Initialize console variables used by the driver.
+ *
+ * @c: Not used.
+ * @opts: Not used.
+ *
+ * Returns:
+ * always 0.
+ */
+static int pti_console_setup(struct console *c, char *opts)
+{
+ pti_console_channel = 0;
+ pti_control_channel = 0;
+ return 0;
+}
+
+/*
+ * pti_console struct, used to capture OS printk()'s and shift
+ * out to the PTI device for debugging. This cannot be
+ * enabled upon boot because of the possibility of eating
+ * any serial console printk's (race condition discovered).
+ * The console should be enabled upon when the tty port is
+ * used for the first time. Since the primary purpose for
+ * the tty port is to hook up syslog to it, the tty port
+ * will be open for a really long time.
+ */
+static struct console pti_console = {
+ .name = TTYNAME,
+ .write = pti_console_write,
+ .device = pti_console_device,
+ .setup = pti_console_setup,
+ .flags = CON_PRINTBUFFER,
+ .index = 0,
+};
+
+/**
+ * pti_port_activate()- Used to start/initialize any items upon
+ * first opening of tty_port().
+ *
+ * @port- The tty port number of the PTI device.
+ * @tty- The tty struct associated with this device.
+ *
+ * Returns:
+ * always returns 0
+ *
+ * Notes: The primary purpose of the PTI tty port 0 is to hook
+ * the syslog daemon to it; thus this port will be open for a
+ * very long time.
+ */
+static int pti_port_activate(struct tty_port *port, struct tty_struct *tty)
+{
+ if (port->tty->index == PTITTY_MINOR_START)
+ console_start(&pti_console);
+ return 0;
+}
+
+/**
+ * pti_port_shutdown()- Used to stop/shutdown any items upon the
+ * last tty port close.
+ *
+ * @port- The tty port number of the PTI device.
+ *
+ * Notes: The primary purpose of the PTI tty port 0 is to hook
+ * the syslog daemon to it; thus this port will be open for a
+ * very long time.
+ */
+static void pti_port_shutdown(struct tty_port *port)
+{
+ if (port->tty->index == PTITTY_MINOR_START)
+ console_stop(&pti_console);
+}
+
+static const struct tty_port_operations tty_port_ops = {
+ .activate = pti_port_activate,
+ .shutdown = pti_port_shutdown,
+};
+
+/*
+ * Note the _probe() call sets everything up and ties the char and tty
+ * to successfully detecting the PTI device on the pci bus.
+ */
+
+/**
+ * pti_pci_probe()- Used to detect pti on the pci bus and set
+ * things up in the driver.
+ *
+ * @pdev- pci_dev struct values for pti.
+ * @ent- pci_device_id struct for pti driver.
+ *
+ * Returns:
+ * 0 for success
+ * otherwise, error
+ */
+static int __devinit pti_pci_probe(struct pci_dev *pdev,
+ const struct pci_device_id *ent)
+{
+ int retval = -EINVAL;
+ int pci_bar = 1;
+
+ dev_dbg(&pdev->dev, "%s %s(%d): PTI PCI ID %04x:%04x\n", __FILE__,
+ __func__, __LINE__, pdev->vendor, pdev->device);
+
+ retval = misc_register(&pti_char_driver);
+ if (retval) {
+ pr_err("%s(%d): CHAR registration failed of pti driver\n",
+ __func__, __LINE__);
+ pr_err("%s(%d): Error value returned: %d\n",
+ __func__, __LINE__, retval);
+ return retval;
+ }
+
+ retval = pci_enable_device(pdev);
+ if (retval != 0) {
+ dev_err(&pdev->dev,
+ "%s: pci_enable_device() returned error %d\n",
+ __func__, retval);
+ return retval;
+ }
+
+ drv_data = kzalloc(sizeof(*drv_data), GFP_KERNEL);
+
+ if (drv_data == NULL) {
+ retval = -ENOMEM;
+ dev_err(&pdev->dev,
+ "%s(%d): kmalloc() returned NULL memory.\n",
+ __func__, __LINE__);
+ return retval;
+ }
+ drv_data->pti_addr = pci_resource_start(pdev, pci_bar);
+
+ retval = pci_request_region(pdev, pci_bar, dev_name(&pdev->dev));
+ if (retval != 0) {
+ dev_err(&pdev->dev,
+ "%s(%d): pci_request_region() returned error %d\n",
+ __func__, __LINE__, retval);
+ kfree(drv_data);
+ return retval;
+ }
+ drv_data->aperture_base = drv_data->pti_addr+APERTURE_14;
+ drv_data->pti_ioaddr =
+ ioremap_nocache((u32)drv_data->aperture_base,
+ APERTURE_LEN);
+ if (!drv_data->pti_ioaddr) {
+ pci_release_region(pdev, pci_bar);
+ retval = -ENOMEM;
+ kfree(drv_data);
+ return retval;
+ }
+
+ pci_set_drvdata(pdev, drv_data);
+
+ tty_port_init(&drv_data->port);
+ drv_data->port.ops = &tty_port_ops;
+
+ tty_register_device(pti_tty_driver, 0, &pdev->dev);
+ tty_register_device(pti_tty_driver, 1, &pdev->dev);
+
+ register_console(&pti_console);
+
+ return retval;
+}
+
+static struct pci_driver pti_pci_driver = {
+ .name = PCINAME,
+ .id_table = pci_ids,
+ .probe = pti_pci_probe,
+ .remove = pti_pci_remove,
+};
+
+/**
+ *
+ * pti_init()- Overall entry/init call to the pti driver.
+ * It starts the registration process with the kernel.
+ *
+ * Returns:
+ * int __init, 0 for success
+ * otherwise value is an error
+ *
+ */
+static int __init pti_init(void)
+{
+ int retval = -EINVAL;
+
+ /* First register module as tty device */
+
+ pti_tty_driver = alloc_tty_driver(1);
+ if (pti_tty_driver == NULL) {
+ pr_err("%s(%d): Memory allocation failed for ptiTTY driver\n",
+ __func__, __LINE__);
+ return -ENOMEM;
+ }
+
+ pti_tty_driver->owner = THIS_MODULE;
+ pti_tty_driver->magic = TTY_DRIVER_MAGIC;
+ pti_tty_driver->driver_name = DRIVERNAME;
+ pti_tty_driver->name = TTYNAME;
+ pti_tty_driver->major = 0;
+ pti_tty_driver->minor_start = PTITTY_MINOR_START;
+ pti_tty_driver->minor_num = PTITTY_MINOR_NUM;
+ pti_tty_driver->num = PTITTY_MINOR_NUM;
+ pti_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
+ pti_tty_driver->subtype = SYSTEM_TYPE_SYSCONS;
+ pti_tty_driver->flags = TTY_DRIVER_REAL_RAW |
+ TTY_DRIVER_DYNAMIC_DEV;
+ pti_tty_driver->init_termios = tty_std_termios;
+
+ tty_set_operations(pti_tty_driver, &pti_tty_driver_ops);
+
+ retval = tty_register_driver(pti_tty_driver);
+ if (retval) {
+ pr_err("%s(%d): TTY registration failed of pti driver\n",
+ __func__, __LINE__);
+ pr_err("%s(%d): Error value returned: %d\n",
+ __func__, __LINE__, retval);
+
+ pti_tty_driver = NULL;
+ return retval;
+ }
+
+ retval = pci_register_driver(&pti_pci_driver);
+
+ if (retval) {
+ pr_err("%s(%d): PCI registration failed of pti driver\n",
+ __func__, __LINE__);
+ pr_err("%s(%d): Error value returned: %d\n",
+ __func__, __LINE__, retval);
+
+ tty_unregister_driver(pti_tty_driver);
+ pr_err("%s(%d): Unregistering TTY part of pti driver\n",
+ __func__, __LINE__);
+ pti_tty_driver = NULL;
+ return retval;
+ }
+
+ return retval;
+}
+
+/**
+ * pti_exit()- Unregisters this module as a tty and pci driver.
+ */
+static void __exit pti_exit(void)
+{
+ int retval;
+
+ tty_unregister_device(pti_tty_driver, 0);
+ tty_unregister_device(pti_tty_driver, 1);
+
+ retval = tty_unregister_driver(pti_tty_driver);
+ if (retval) {
+ pr_err("%s(%d): TTY unregistration failed of pti driver\n",
+ __func__, __LINE__);
+ pr_err("%s(%d): Error value returned: %d\n",
+ __func__, __LINE__, retval);
+ }
+
+ pci_unregister_driver(&pti_pci_driver);
+
+ retval = misc_deregister(&pti_char_driver);
+ if (retval) {
+ pr_err("%s(%d): CHAR unregistration failed of pti driver\n",
+ __func__, __LINE__);
+ pr_err("%s(%d): Error value returned: %d\n",
+ __func__, __LINE__, retval);
+ }
+
+ unregister_console(&pti_console);
+ return;
+}
+
+module_init(pti_init);
+module_exit(pti_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Ken Mills, Jay Freyensee");
+MODULE_DESCRIPTION("PTI Driver");
+