msm: smd_tty: Add IPC logging for smd_tty
IPC Logging infrastructure logs information about the SMD TTY module to a
dedicated internal buffer. This allows debugging the events leading up to
a crash and it allows debugging from userspace without the overhead of the
kernel log.
Change-Id: Ic1ccf4f342127405b26c75957401795702091c43
Signed-off-by: Zaheerulla Meer <zmeer@codeaurora.org>
diff --git a/arch/arm/mach-msm/smd_tty.c b/arch/arm/mach-msm/smd_tty.c
index 5969a3c..21e1bf4 100644
--- a/arch/arm/mach-msm/smd_tty.c
+++ b/arch/arm/mach-msm/smd_tty.c
@@ -32,13 +32,30 @@
#include <mach/msm_smd.h>
#include <mach/subsystem_restart.h>
#include <mach/socinfo.h>
+#include <mach/msm_ipc_logging.h>
#include "smd_private.h"
#define MAX_SMD_TTYS 37
#define MAX_TTY_BUF_SIZE 2048
#define MAX_RA_WAKE_LOCK_NAME_LEN 32
+#define SMD_TTY_LOG_PAGES 2
+#define SMD_TTY_INFO(buf...) \
+do { \
+ if (smd_tty_log_ctx) { \
+ ipc_log_string(smd_tty_log_ctx, buf); \
+ } \
+} while (0)
+
+#define SMD_TTY_ERR(buf...) \
+do { \
+ if (smd_tty_log_ctx) \
+ ipc_log_string(smd_tty_log_ctx, buf); \
+ pr_err(buf); \
+} while (0)
+
+static void *smd_tty_log_ctx;
static DEFINE_MUTEX(smd_tty_lock);
static uint smd_tty_modem_wait;
@@ -165,7 +182,9 @@
** context here and nobody else could 'steal' our
** characters.
*/
- printk(KERN_ERR "OOPS - smd_tty_buffer mismatch?!");
+ SMD_TTY_ERR(
+ "%s - Possible smd_tty_buffer mismatch for %s",
+ __func__, info->ch->name);
}
wake_lock_timeout(&info->wake_lock, HZ / 2);
@@ -299,14 +318,15 @@
1000));
if (res == 0) {
- pr_err("Timed out waiting for SMD"
- " channel\n");
+ SMD_TTY_INFO(
+ "Timed out waiting for SMD channel %s",
+ smd_tty[n].smd->port_name);
res = -ETIMEDOUT;
goto release_pil;
} else if (res < 0) {
- pr_err("Error waiting for SMD channel:"
- " %d\n",
- res);
+ SMD_TTY_INFO(
+ "Error waiting for SMD channel %s : %d\n",
+ smd_tty[n].smd->port_name, res);
goto release_pil;
}
@@ -329,8 +349,10 @@
&info->ch, info,
smd_tty_notify);
if (res < 0) {
- pr_err("%s: %s open failed %d\n", __func__,
- smd_tty[n].smd->port_name, res);
+ SMD_TTY_INFO(
+ "%s: %s open failed %d\n",
+ __func__, smd_tty[n].smd->port_name,
+ res);
goto release_pil;
}
@@ -340,12 +362,16 @@
if (res == 0)
res = -ETIMEDOUT;
if (res < 0) {
- pr_err("%s: wait for %s smd_open failed %d\n",
+ SMD_TTY_INFO(
+ "%s: wait for %s smd_open failed %d\n",
__func__, smd_tty[n].smd->port_name,
res);
goto release_pil;
}
res = 0;
+ SMD_TTY_INFO("%s with PID %u opened port %s",
+ current->comm, current->pid,
+ smd_tty[n].smd->port_name);
}
}
@@ -382,6 +408,9 @@
wake_lock_destroy(&info->wake_lock);
wake_lock_destroy(&info->ra_wake_lock);
}
+ SMD_TTY_INFO("%s with PID %u closed port %s",
+ current->comm, current->pid,
+ info->smd->port_name);
tty->driver_data = 0;
del_timer(&info->buf_req_timer);
if (info->ch) {
@@ -430,6 +459,8 @@
}
if (len > avail)
len = avail;
+ SMD_TTY_INFO("[WRITE]: PID %u -> port %s %x bytes",
+ current->pid, info->smd->port_name, len);
return smd_write(info->ch, buf, len);
}
@@ -480,6 +511,8 @@
tiocm |= TIOCM_OUT2;
info->in_reset_updated = 0;
}
+ SMD_TTY_INFO("PID %u --> %s TIOCM is %x ",
+ current->pid, __func__, tiocm);
spin_unlock_irqrestore(&info->reset_lock, flags);
return tiocm;
@@ -493,6 +526,8 @@
if (info->in_reset)
return -ENETRESET;
+ SMD_TTY_INFO("PID %u --> %s Set: %x Clear: %x",
+ current->pid, __func__, set, clear);
return smd_tiocmset(info->ch, set, clear);
}
@@ -540,11 +575,25 @@
return 0;
}
}
- pr_err("%s: unknown device '%s'\n", __func__, pdev->name);
+ SMD_TTY_ERR("[ERR]%s: unknown device '%s'\n", __func__, pdev->name);
return -ENODEV;
}
+/**
+ * smd_tty_log_init()- Init function for IPC logging
+ *
+ * Initialize the buffer that is used to provide the log information
+ * pertaining to the smd_tty module.
+ */
+static void smd_tty_log_init(void)
+{
+ smd_tty_log_ctx = ipc_log_context_create(SMD_TTY_LOG_PAGES,
+ "smd_tty");
+ if (!smd_tty_log_ctx)
+ pr_err("%s: Unable to create IPC log", __func__);
+}
+
static struct tty_driver *smd_tty_driver;
static int __init smd_tty_init(void)
@@ -554,9 +603,12 @@
int idx;
struct tty_port *port;
+ smd_tty_log_init();
smd_tty_driver = alloc_tty_driver(MAX_SMD_TTYS);
- if (smd_tty_driver == 0)
+ if (smd_tty_driver == 0) {
+ SMD_TTY_ERR("%s - Driver allocation failed", __func__);
return -ENOMEM;
+ }
smd_tty_driver->owner = THIS_MODULE;
smd_tty_driver->driver_name = "smd_tty_driver";
@@ -577,7 +629,7 @@
ret = tty_register_driver(smd_tty_driver);
if (ret) {
put_tty_driver(smd_tty_driver);
- pr_err("%s: driver registration failed %d\n", __func__, ret);
+ SMD_TTY_ERR("%s: driver registration failed %d", __func__, ret);
return ret;
}
@@ -628,7 +680,8 @@
ret = platform_driver_register(&smd_tty[idx].driver);
if (ret) {
- pr_err("%s: init failed %d (%d)\n", __func__, idx, ret);
+ SMD_TTY_ERR(
+ "%s: init failed %d (%d)", __func__, idx, ret);
smd_tty[idx].driver.probe = NULL;
goto out;
}