[PATCH v6 3/4] drm/mediatek: add the mipitx driving control

From: Jitao Shi
Date: Sat Apr 11 2020 - 03:44:40 EST


Add a property in device tree to control the driving by different
board.

Reviewed-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
Reviewed-by: Matthias Brugger <matthias.bgg@xxxxxxxxx>
Signed-off-by: Jitao Shi <jitao.shi@xxxxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_mipi_tx.c | 14 ++++++++++++++
drivers/gpu/drm/mediatek/mtk_mipi_tx.h | 1 +
drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 7 +++++++
3 files changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
index e4d34484ecc8..e301af64809e 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
@@ -125,6 +125,20 @@ static int mtk_mipi_tx_probe(struct platform_device *pdev)
return ret;
}

+ ret = of_property_read_u32(dev->of_node, "drive-strength-microamp",
+ &mipi_tx->mipitx_drive);
+ /* If can't get the "mipi_tx->mipitx_drive", set it default 0x8 */
+ if (ret < 0)
+ mipi_tx->mipitx_drive = 4600;
+
+ /* check the mipitx_drive valid */
+ if (mipi_tx->mipitx_drive > 6000 || mipi_tx->mipitx_drive < 3000) {
+ dev_warn(dev, "drive-strength-microamp is invalid %d, not in 3000 ~ 6000\n",
+ mipi_tx->mipitx_drive);
+ mipi_tx->mipitx_drive = clamp_val(mipi_tx->mipitx_drive, 3000,
+ 6000);
+ }
+
ref_clk_name = __clk_get_name(ref_clk);

ret = of_property_read_string(dev->of_node, "clock-output-names",
diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
index 413f35d86219..eea44327fe9f 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
@@ -27,6 +27,7 @@ struct mtk_mipi_tx {
struct device *dev;
void __iomem *regs;
u32 data_rate;
+ u32 mipitx_drive;
const struct mtk_mipitx_data *driver_data;
struct clk_hw pll_hw;
struct clk *pll;
diff --git a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
index 91f08a351fd0..e4cc967750cb 100644
--- a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
@@ -17,6 +17,9 @@
#define RG_DSI_BG_CORE_EN BIT(7)
#define RG_DSI_PAD_TIEL_SEL BIT(8)

+#define MIPITX_VOLTAGE_SEL 0x0010
+#define RG_DSI_HSTX_LDO_REF_SEL (0xf << 6)
+
#define MIPITX_PLL_PWR 0x0028
#define MIPITX_PLL_CON0 0x002c
#define MIPITX_PLL_CON1 0x0030
@@ -123,6 +126,10 @@ static void mtk_mipi_tx_power_on_signal(struct phy *phy)
mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_D3_SW_CTL_EN, DSI_SW_CTL_EN);
mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_CK_SW_CTL_EN, DSI_SW_CTL_EN);

+ mtk_mipi_tx_update_bits(mipi_tx, MIPITX_VOLTAGE_SEL,
+ RG_DSI_HSTX_LDO_REF_SEL,
+ (mipi_tx->mipitx_drive - 3000) / 200 << 6);
+
mtk_mipi_tx_set_bits(mipi_tx, MIPITX_CK_CKMODE_EN, DSI_CK_CKMODE_EN);
}

--
2.21.0