diff mbox series

[v2,05/13] drm/bridge: lt9611: fix clock calculation

Message ID 20230108165656.136871-6-dmitry.baryshkov@linaro.org (mailing list archive)
State Superseded
Headers show
Series drm/bridge: lt9611: several fixes and improvements | expand

Commit Message

Dmitry Baryshkov Jan. 8, 2023, 4:56 p.m. UTC 
Instead of having several fixed values for the pcr register, calculate
it before programming. This allows the bridge to support most of the
display modes.

Fixes: 23278bf54afe ("drm/bridge: Introduce LT9611 DSI to HDMI bridge")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/bridge/lontium-lt9611.c | 32 +++++++++++--------------
 1 file changed, 14 insertions(+), 18 deletions(-)

Comments

Neil Armstrong Jan. 12, 2023, 9:28 a.m. UTC | #1 
On 08/01/2023 17:56, Dmitry Baryshkov wrote:
> Instead of having several fixed values for the pcr register, calculate
> it before programming. This allows the bridge to support most of the
> display modes.
> 
> Fixes: 23278bf54afe ("drm/bridge: Introduce LT9611 DSI to HDMI bridge")
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
> ---
>   drivers/gpu/drm/bridge/lontium-lt9611.c | 32 +++++++++++--------------
>   1 file changed, 14 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
> index f377052a45a4..e2799a0df8f8 100644
> --- a/drivers/gpu/drm/bridge/lontium-lt9611.c
> +++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
> @@ -192,8 +192,9 @@ static void lt9611_mipi_video_setup(struct lt9611 *lt9611,
>   	regmap_write(lt9611->regmap, 0x831b, (u8)(hsync_porch % 256));
>   }
>   
> -static void lt9611_pcr_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode)
> +static void lt9611_pcr_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode, unsigned int postdiv)
>   {
> +	unsigned int pcr_m = mode->clock * 5 * postdiv / 27000;
>   	const struct reg_sequence reg_cfg[] = {
>   		{ 0x830b, 0x01 },
>   		{ 0x830c, 0x10 },
> @@ -236,24 +237,14 @@ static void lt9611_pcr_setup(struct lt9611 *lt9611, const struct drm_display_mod
>   	else
>   		regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
>   
> -	switch (mode->hdisplay) {
> -	case 640:
> -		regmap_write(lt9611->regmap, 0x8326, 0x14);
> -		break;
> -	case 1920:
> -		regmap_write(lt9611->regmap, 0x8326, 0x37);
> -		break;
> -	case 3840:
> -		regmap_write(lt9611->regmap, 0x8326, 0x37);
> -		break;
> -	}
> +	regmap_write(lt9611->regmap, 0x8326, pcr_m);
>   
>   	/* pcr rst */
>   	regmap_write(lt9611->regmap, 0x8011, 0x5a);
>   	regmap_write(lt9611->regmap, 0x8011, 0xfa);
>   }
>   
> -static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode)
> +static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode, unsigned int *postdiv)
>   {
>   	unsigned int pclk = mode->clock;
>   	const struct reg_sequence reg_cfg[] = {
> @@ -271,12 +262,16 @@ static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode
>   
>   	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
>   
> -	if (pclk > 150000)
> +	if (pclk > 150000) {
>   		regmap_write(lt9611->regmap, 0x812d, 0x88);
> -	else if (pclk > 70000)
> +		*postdiv = 1;
> +	} else if (pclk > 70000) {
>   		regmap_write(lt9611->regmap, 0x812d, 0x99);
> -	else
> +		*postdiv = 2;
> +	} else {
>   		regmap_write(lt9611->regmap, 0x812d, 0xaa);
> +		*postdiv = 4;
> +	}
>   
>   	/*
>   	 * first divide pclk by 2 first
> @@ -895,14 +890,15 @@ static void lt9611_bridge_mode_set(struct drm_bridge *bridge,
>   {
>   	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
>   	struct hdmi_avi_infoframe avi_frame;
> +	unsigned int postdiv;
>   	int ret;
>   
>   	lt9611_bridge_pre_enable(bridge);
>   
>   	lt9611_mipi_input_digital(lt9611, mode);
> -	lt9611_pll_setup(lt9611, mode);
> +	lt9611_pll_setup(lt9611, mode, &postdiv);
>   	lt9611_mipi_video_setup(lt9611, mode);
> -	lt9611_pcr_setup(lt9611, mode);
> +	lt9611_pcr_setup(lt9611, mode, postdiv);
>   
>   	ret = drm_hdmi_avi_infoframe_from_display_mode(&avi_frame,
>   						       &lt9611->connector,


Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
index f377052a45a4..e2799a0df8f8 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
@@ -192,8 +192,9 @@  static void lt9611_mipi_video_setup(struct lt9611 *lt9611,
 	regmap_write(lt9611->regmap, 0x831b, (u8)(hsync_porch % 256));
 }
 
-static void lt9611_pcr_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode)
+static void lt9611_pcr_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode, unsigned int postdiv)
 {
+	unsigned int pcr_m = mode->clock * 5 * postdiv / 27000;
 	const struct reg_sequence reg_cfg[] = {
 		{ 0x830b, 0x01 },
 		{ 0x830c, 0x10 },
@@ -236,24 +237,14 @@  static void lt9611_pcr_setup(struct lt9611 *lt9611, const struct drm_display_mod
 	else
 		regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
 
-	switch (mode->hdisplay) {
-	case 640:
-		regmap_write(lt9611->regmap, 0x8326, 0x14);
-		break;
-	case 1920:
-		regmap_write(lt9611->regmap, 0x8326, 0x37);
-		break;
-	case 3840:
-		regmap_write(lt9611->regmap, 0x8326, 0x37);
-		break;
-	}
+	regmap_write(lt9611->regmap, 0x8326, pcr_m);
 
 	/* pcr rst */
 	regmap_write(lt9611->regmap, 0x8011, 0x5a);
 	regmap_write(lt9611->regmap, 0x8011, 0xfa);
 }
 
-static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode)
+static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode *mode, unsigned int *postdiv)
 {
 	unsigned int pclk = mode->clock;
 	const struct reg_sequence reg_cfg[] = {
@@ -271,12 +262,16 @@  static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode
 
 	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));
 
-	if (pclk > 150000)
+	if (pclk > 150000) {
 		regmap_write(lt9611->regmap, 0x812d, 0x88);
-	else if (pclk > 70000)
+		*postdiv = 1;
+	} else if (pclk > 70000) {
 		regmap_write(lt9611->regmap, 0x812d, 0x99);
-	else
+		*postdiv = 2;
+	} else {
 		regmap_write(lt9611->regmap, 0x812d, 0xaa);
+		*postdiv = 4;
+	}
 
 	/*
 	 * first divide pclk by 2 first
@@ -895,14 +890,15 @@  static void lt9611_bridge_mode_set(struct drm_bridge *bridge,
 {
 	struct lt9611 *lt9611 = bridge_to_lt9611(bridge);
 	struct hdmi_avi_infoframe avi_frame;
+	unsigned int postdiv;
 	int ret;
 
 	lt9611_bridge_pre_enable(bridge);
 
 	lt9611_mipi_input_digital(lt9611, mode);
-	lt9611_pll_setup(lt9611, mode);
+	lt9611_pll_setup(lt9611, mode, &postdiv);
 	lt9611_mipi_video_setup(lt9611, mode);
-	lt9611_pcr_setup(lt9611, mode);
+	lt9611_pcr_setup(lt9611, mode, postdiv);
 
 	ret = drm_hdmi_avi_infoframe_from_display_mode(&avi_frame,
 						       &lt9611->connector,