[ARM] msm: add /proc/last_radio_log when supported by the modem.

Signed-off-by: Iliyan Malchev <malchev@google.com>
Signed-off-by: Daniel Walker <dwalker@codeaurora.org>

arch/arm/mach-msm/Makefile

@@ -6,6 +6,7 @@ obj-y += acpuclock-arm11.o
 obj-y += clock.o clock-7x01a.o
 
 obj-$(CONFIG_MSM_SMD) += smd.o smd_debug.o
+obj-$(CONFIG_MSM_SMD) += last_radio_log.o
 
 obj-$(CONFIG_MACH_TROUT) += board-trout.o
 obj-$(CONFIG_MACH_HALIBUT) += board-halibut.o

arch/arm/mach-msm/last_radio_log.c

@@ -0,0 +1,82 @@
+/* arch/arm/mach-msm/last_radio_log.c
+ *
+ * Extract the log from a modem crash though SMEM
+ *
+ * Copyright (C) 2007 Google, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/uaccess.h>
+
+#include "smd_private.h"
+
+static void *radio_log_base;
+static size_t radio_log_size;
+
+extern void *smem_item(unsigned id, unsigned *size);
+
+static ssize_t last_radio_log_read(struct file *file, char __user *buf,
+			size_t len, loff_t *offset)
+{
+	loff_t pos = *offset;
+	ssize_t count;
+
+	if (pos >= radio_log_size)
+		return 0;
+
+	count = min(len, (size_t)(radio_log_size - pos));
+	if (copy_to_user(buf, radio_log_base + pos, count)) {
+		pr_err("%s: copy to user failed\n", __func__);
+		return -EFAULT;
+	}
+
+	*offset += count;
+	return count;
+}
+
+static struct file_operations last_radio_log_fops = {
+	.read = last_radio_log_read
+};
+
+void msm_init_last_radio_log(struct module *owner)
+{
+	struct proc_dir_entry *entry;
+
+	if (last_radio_log_fops.owner) {
+		pr_err("%s: already claimed\n", __func__);
+		return;
+	}
+
+	radio_log_base = smem_item(SMEM_CLKREGIM_BSP, &radio_log_size);
+	if (!radio_log_base) {
+		pr_err("%s: could not retrieve SMEM_CLKREGIM_BSP\n", __func__);
+		return;
+	}
+
+	entry = create_proc_entry("last_radio_log", S_IFREG | S_IRUGO, NULL);
+	if (!entry) {
+		pr_err("%s: could not create proc entry for radio log\n",
+				__func__);
+		return;
+	}
+
+	pr_err("%s: last radio log is %d bytes long\n", __func__,
+		radio_log_size);
+	last_radio_log_fops.owner = owner;
+	entry->proc_fops = &last_radio_log_fops;
+	entry->size = radio_log_size;
+}
+EXPORT_SYMBOL(msm_init_last_radio_log);

arch/arm/mach-msm/smd.c

@@ -1038,6 +1038,8 @@ int smd_core_init(void)
 	return 0;
 }
 
+extern void msm_init_last_radio_log(struct module *);
+
 static int __init msm_smd_probe(struct platform_device *pdev)
 {
 	pr_info("smd_init()\n");
@@ -1053,6 +1055,8 @@ static int __init msm_smd_probe(struct platform_device *pdev)
 
 	msm_check_for_modem_crash = check_for_modem_crash;
 
+	msm_init_last_radio_log(THIS_MODULE);
+
 	smd_initialized = 1;
 
 	return 0;