[PATCH v3 1/6] drm: atmel-hlcdc: add config option for clock selection

[Claudiu.Beznea at microchip.com]

From: Claudiu Beznea <claudiu.beznea at microchip.com>

SAM9x60 LCD Controller has no option to select clock source as previous
controllers have. To be able to use the same driver even for this LCD
controller add a config option to know if controller supports this.

Signed-off-by: Claudiu Beznea <claudiu.beznea at microchip.com>
Reviewed-by: Sam Ravnborg <sam at ravnborg.org>
---
 drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c | 12 +++++++-----
 drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h   |  2 ++
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
index 8070a558d7b1..957e6d2fb00f 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_crtc.c
@@ -78,7 +78,8 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
 	unsigned long mode_rate;
 	struct videomode vm;
 	unsigned long prate;
-	unsigned int cfg;
+	unsigned int mask = ATMEL_HLCDC_CLKDIV_MASK | ATMEL_HLCDC_CLKPOL;
+	unsigned int cfg = 0;
 	int div;
 
 	vm.vfront_porch = adj->crtc_vsync_start - adj->crtc_vdisplay;
@@ -101,7 +102,10 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
 		     (adj->crtc_hdisplay - 1) |
 		     ((adj->crtc_vdisplay - 1) << 16));
 
-	cfg = ATMEL_HLCDC_CLKSEL;
+	if (!crtc->dc->desc->fixed_clksrc) {
+		cfg |= ATMEL_HLCDC_CLKSEL;
+		mask |= ATMEL_HLCDC_CLKSEL;
+	}
 
 	prate = 2 * clk_get_rate(crtc->dc->hlcdc->sys_clk);
 	mode_rate = adj->crtc_clock * 1000;
@@ -132,9 +136,7 @@ static void atmel_hlcdc_crtc_mode_set_nofb(struct drm_crtc *c)
 
 	cfg |= ATMEL_HLCDC_CLKDIV(div);
 
-	regmap_update_bits(regmap, ATMEL_HLCDC_CFG(0),
-			   ATMEL_HLCDC_CLKSEL | ATMEL_HLCDC_CLKDIV_MASK |
-			   ATMEL_HLCDC_CLKPOL, cfg);
+	regmap_update_bits(regmap, ATMEL_HLCDC_CFG(0), mask, cfg);
 
 	cfg = 0;
 
diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h
index 70bd540d644e..0155efb9c443 100644
--- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h
+++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_dc.h
@@ -328,6 +328,7 @@ atmel_hlcdc_layer_to_plane(struct atmel_hlcdc_layer *layer)
  * @max_hpw: maximum horizontal back/front porch width
  * @conflicting_output_formats: true if RGBXXX output formats conflict with
  *				each other.
+ * @fixed_clksrc: true if clock source is fixed
  * @layers: a layer description table describing available layers
  * @nlayers: layer description table size
  */
@@ -340,6 +341,7 @@ struct atmel_hlcdc_dc_desc {
 	int max_vpw;
 	int max_hpw;
 	bool conflicting_output_formats;
+	bool fixed_clksrc;
 	const struct atmel_hlcdc_layer_desc *layers;
 	int nlayers;
 };
-- 
2.7.4