1 files changed, 76 insertions, 3 deletions

diff --git a/drivers/platform/x86/touchscreen_dmi.c b/drivers/platform/x86/touchscreen_dmi.c
index c6a10ec2c83f..b021fb9e579e 100644
--- a/drivers/platform/x86/touchscreen_dmi.c
+++ b/drivers/platform/x86/touchscreen_dmi.c
@@ -9,10 +9,13 @@
  */
 
 #include <linux/acpi.h>
+#include <linux/ctype.h>
 #include <linux/device.h>
 #include <linux/dmi.h>
 #include <linux/efi_embedded_fw.h>
 #include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/kstrtox.h>
 #include <linux/notifier.h>
 #include <linux/property.h>
 #include <linux/string.h>
@@ -1817,7 +1820,7 @@ const struct dmi_system_id touchscreen_dmi_table[] = {
 	{ }
 };
 
-static const struct ts_dmi_data *ts_data;
+static struct ts_dmi_data *ts_data;
 
 static void ts_dmi_add_props(struct i2c_client *client)
 {
@@ -1852,6 +1855,64 @@ static int ts_dmi_notifier_call(struct notifier_block *nb,
 	return 0;
 }
 
+#define MAX_CMDLINE_PROPS 16
+
+static struct property_entry ts_cmdline_props[MAX_CMDLINE_PROPS + 1];
+
+static struct ts_dmi_data ts_cmdline_data = {
+	.properties = ts_cmdline_props,
+};
+
+static int __init ts_parse_props(char *str)
+{
+	/* Save the original str to show it on syntax errors */
+	char orig_str[256];
+	char *name, *value;
+	u32 u32val;
+	int i, ret;
+
+	strscpy(orig_str, str, sizeof(orig_str));
+
+	/*
+	 * str is part of the static_command_line from init/main.c and poking
+	 * holes in that by writing 0 to it is allowed, as is taking long
+	 * lasting references to it.
+	 */
+	ts_cmdline_data.acpi_name = strsep(&str, ":");
+
+	for (i = 0; i < MAX_CMDLINE_PROPS; i++) {
+		name = strsep(&str, ":");
+		if (!name || !name[0])
+			break;
+
+		/* Replace '=' with 0 and make value point past '=' or NULL */
+		value = name;
+		strsep(&value, "=");
+		if (!value) {
+			ts_cmdline_props[i] = PROPERTY_ENTRY_BOOL(name);
+		} else if (isdigit(value[0])) {
+			ret = kstrtou32(value, 0, &u32val);
+			if (ret)
+				goto syntax_error;
+
+			ts_cmdline_props[i] = PROPERTY_ENTRY_U32(name, u32val);
+		} else {
+			ts_cmdline_props[i] = PROPERTY_ENTRY_STRING(name, value);
+		}
+	}
+
+	if (!i || str)
+		goto syntax_error;
+
+	ts_data = &ts_cmdline_data;
+	return 1;
+
+syntax_error:
+	pr_err("Invalid '%s' value for 'i2c_touchscreen_props='\n", orig_str);
+	return 1; /* "i2c_touchscreen_props=" is still a known parameter */
+}
+__setup("i2c_touchscreen_props=", ts_parse_props);
+
 static struct notifier_block ts_dmi_notifier = {
 	.notifier_call = ts_dmi_notifier_call,
 };
@@ -1859,13 +1920,25 @@ static struct notifier_block ts_dmi_notifier = {
 static int __init ts_dmi_init(void)
 {
 	const struct dmi_system_id *dmi_id;
+	struct ts_dmi_data *ts_data_dmi;
 	int error;
 
 	dmi_id = dmi_first_match(touchscreen_dmi_table);
-	if (!dmi_id)
+	ts_data_dmi = dmi_id ? dmi_id->driver_data : NULL;
+
+	if (ts_data) {
+		/*
+		 * Kernel cmdline provided data takes precedence, copy over
+		 * DMI efi_embedded_fw info if available.
+		 */
+		if (ts_data_dmi)
+			ts_data->embedded_fw = ts_data_dmi->embedded_fw;
+	} else if (ts_data_dmi) {
+		ts_data = ts_data_dmi;
+	} else {
 		return 0; /* Not an error */
+	}
 
-	ts_data = dmi_id->driver_data;
 	/* Some dmi table entries only provide an efi_embedded_fw_desc */
 	if (!ts_data->properties)
 		return 0;