video: tegra: dc: support disp mode override via boot args

Allows overidding the default disp mode without having to recompile
the kernel. Boot args can be specified in the following format:

disp_params=<rgb|hdmi|dsi>:pclk,h_active,v_active,h_ref_to_sync,
v_ref_to_sync,h_sync_width,v_sync_width,h_back_porch,v_back_porch,
h_front_porch,v_front_porch;<rgb|hdmi|dsi>:pclk,h_active,...

Bug 969088

Change-Id: Id0acf608de145493f6749d5b799d4bbb8162ba72
Signed-off-by: Nirav Patel <nipatel@nvidia.com>
Reviewed-on: http://git-master/r/104604
Reviewed-by: Rohan Somvanshi <rsomvanshi@nvidia.com>
Tested-by: Rohan Somvanshi <rsomvanshi@nvidia.com>

1 files changed, 94 insertions, 1 deletions

diff --git a/drivers/video/tegra/dc/dc.c b/drivers/video/tegra/dc/dc.c
index e0c4027656f9..77cd19e6f870 100644
--- a/drivers/video/tegra/dc/dc.c
+++ b/drivers/video/tegra/dc/dc.c
@@ -73,6 +73,8 @@ static struct fb_videomode tegra_dc_hdmi_fallback_mode = {
 	.sync = 0,
 };
 
+static struct tegra_dc_mode override_disp_mode[3];
+
 static void _tegra_dc_controller_disable(struct tegra_dc *dc);
 
 struct tegra_dc *tegra_dcs[TEGRA_MAX_DC];
@@ -712,11 +714,27 @@ void tegra_dc_set_out_pin_polars(struct tegra_dc *dc,
 	tegra_dc_writel(dc, pol3, DC_COM_PIN_OUTPUT_POLARITY3);
 }
 
+static struct tegra_dc_mode *tegra_dc_get_override_mode(struct tegra_dc *dc)
+{
+	if (dc->out->type == TEGRA_DC_OUT_RGB ||
+		dc->out->type == TEGRA_DC_OUT_HDMI ||
+		dc->out->type == TEGRA_DC_OUT_DSI)
+		return override_disp_mode[dc->out->type].pclk ?
+			&override_disp_mode[dc->out->type] : NULL;
+	else
+		return NULL;
+}
+
 static void tegra_dc_set_out(struct tegra_dc *dc, struct tegra_dc_out *out)
 {
+	struct tegra_dc_mode *mode;
+
 	dc->out = out;
+	mode = tegra_dc_get_override_mode(dc);
 
-	if (out->n_modes > 0)
+	if (mode)
+		tegra_dc_set_mode(dc, mode);
+	else if (out->n_modes > 0)
 		tegra_dc_set_mode(dc, &dc->out->modes[0]);
 
 	switch (out->type) {
@@ -1609,6 +1627,7 @@ static int tegra_dc_probe(struct nvhost_device *ndev,
 	struct nvhost_device_id *id_table)
 {
 	struct tegra_dc *dc;
+	struct tegra_dc_mode *mode;
 	struct clk *clk;
 	struct clk *emc_clk;
 	struct resource	*res;
@@ -1777,6 +1796,12 @@ static int tegra_dc_probe(struct nvhost_device *ndev,
 				tegra_dc_fmt_bpp(fmt);
 		}
 
+		mode = tegra_dc_get_override_mode(dc);
+		if (mode) {
+			dc->pdata->fb->xres = mode->h_active;
+			dc->pdata->fb->yres = mode->v_active;
+		}
+
 		dc->fb = tegra_fb_register(ndev, dc, dc->pdata->fb, fb_mem);
 		if (IS_ERR_OR_NULL(dc->fb))
 			dc->fb = NULL;
@@ -1955,6 +1980,74 @@ struct nvhost_driver tegra_dc_driver = {
 	.shutdown = tegra_dc_shutdown,
 };
 
+#ifndef MODULE
+static int __init parse_disp_params(char *options, struct tegra_dc_mode *mode)
+{
+	int i, params[11];
+	char *p;
+
+	for (i = 0; i < ARRAY_SIZE(params); i++) {
+		if ((p = strsep(&options, ",")) != NULL) {
+			if (*p)
+				params[i] = simple_strtoul(p, &p, 10);
+		} else
+			return -EINVAL;
+	}
+
+	if ((mode->pclk = params[0]) == 0)
+		return -EINVAL;
+
+	mode->h_active      = params[1];
+	mode->v_active      = params[2];
+	mode->h_ref_to_sync = params[3];
+	mode->v_ref_to_sync = params[4];
+	mode->h_sync_width  = params[5];
+	mode->v_sync_width  = params[6];
+	mode->h_back_porch  = params[7];
+	mode->v_back_porch  = params[8];
+	mode->h_front_porch = params[9];
+	mode->v_front_porch = params[10];
+
+	return 0;
+}
+
+static int __init tegra_dc_mode_override(char *str)
+{
+	char *p = str, *options;
+
+	if (!p || !*p)
+		return -EINVAL;
+
+	p = strstr(str, "hdmi:");
+	if (p) {
+		p += 5;
+		options = strsep(&p, ";");
+		if (parse_disp_params(options, &override_disp_mode[TEGRA_DC_OUT_HDMI]))
+			return -EINVAL;
+	}
+
+	p = strstr(str, "rgb:");
+	if (p) {
+		p += 4;
+		options = strsep(&p, ";");
+		if (parse_disp_params(options, &override_disp_mode[TEGRA_DC_OUT_RGB]))
+			return -EINVAL;
+	}
+
+	p = strstr(str, "dsi:");
+	if (p) {
+		p += 4;
+		options = strsep(&p, ";");
+		if (parse_disp_params(options, &override_disp_mode[TEGRA_DC_OUT_DSI]))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+__setup("disp_params=", tegra_dc_mode_override);
+#endif
+
 static int __init tegra_dc_module_init(void)
 {
 	int ret = tegra_dc_ext_module_init();