From: Ryan Harkin <ryan.harkin@linaro.org>
Date: Wed, 16 Apr 2014 17:08:01 +0000 (+0100)
Subject: amba-clcd: set video mode via module parameter on kernel commandline
X-Git-Tag: firefly_0821_release~3680^2~36^2~21^2~1
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6846e7822c4cab5a84672baace3b768c2d0db142;p=firefly-linux-kernel-4.4.55.git

amba-clcd: set video mode via module parameter on kernel commandline

Specifying the module parameter "amba-clcd.mode=<mode>" will over-ride
the default mode used when the driver is initialised.

Where <mode> can either be VGA or XVGA (the default).

Signed-off-by: Ryan Harkin <ryan.harkin@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
---

diff --git a/drivers/video/amba-clcd.c b/drivers/video/amba-clcd.c
index 94a1998338da..dba653f6badc 100644
--- a/drivers/video/amba-clcd.c
+++ b/drivers/video/amba-clcd.c
@@ -45,6 +45,8 @@
 
 /* This is limited to 16 characters when displayed by X startup */
 static const char *clcd_name = "CLCD FB";
+static char *def_mode;
+module_param_named(mode, def_mode, charp, 0);
 
 /*
  * Unfortunately, the enable/disable functions may be called either from
@@ -763,10 +765,18 @@ static int clcdfb_dt_init(struct clcd_fb *fb)
 	na = of_n_addr_cells(node);
 	ns = of_n_size_cells(node);
 
-	if (WARN_ON(of_property_read_string(node, "mode", &mode)))
-		return -ENODEV;
+	if (def_mode && strlen(def_mode) > 0) {
+		fb->panel = clcdfb_get_panel(def_mode);
+		if (!fb->panel)
+			printk(KERN_ERR "CLCD: invalid mode specified on the command line (%s)\n", def_mode);
+	}
+
+	if (!fb->panel) {
+		if (WARN_ON(of_property_read_string(node, "mode", &mode)))
+			return -ENODEV;
+		fb->panel = clcdfb_get_panel(mode);
+	}
 
-	fb->panel = clcdfb_get_panel(mode);
 	if (!fb->panel)
 		return -EINVAL;
 	fb->fb.fix.smem_len = fb->panel->mode.xres * fb->panel->mode.yres * 2;