Re: [PATCH v5 4/4] drm/mediatek: config mipitx impedance with calibration data

2020-04-10 Thread Chun-Kuang Hu
Hi, Jitao:

Jitao Shi  於 2020年4月10日 週五 下午12:33寫道:
>
> Read calibration data from nvmem, and config mipitx impedance with
> calibration data to make sure their impedance are 100ohm.
>
> Signed-off-by: Jitao Shi 
> ---
>  drivers/gpu/drm/mediatek/mtk_mipi_tx.c| 40 +++
>  drivers/gpu/drm/mediatek/mtk_mipi_tx.h|  3 ++
>  drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 21 ++
>  3 files changed, 64 insertions(+)
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c 
> b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
> index e301af64809e..5e91fc2c1318 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
> +++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
> @@ -88,6 +88,44 @@ static const struct phy_ops mtk_mipi_tx_ops = {
> .owner = THIS_MODULE,
>  };
>
> +static void mtk_mipi_tx_get_calibration_datal(struct mtk_mipi_tx *mipi_tx)
> +{
> +   struct nvmem_cell *cell;
> +   size_t len;
> +   u32 *buf;
> +
> +   memset(mipi_tx->rt_code, 0, sizeof(mipi_tx->rt_code));

You use kzalloc() to allocate mipi_tx, so this is already zero-initialized.

> +   cell = nvmem_cell_get(mipi_tx->dev, "calibration-data");
> +   if (IS_ERR(cell)) {
> +   dev_info(mipi_tx->dev, "can't get nvmem_cell_get, ignore 
> it\n");
> +   } else {

If you return when error, you could get rid of the 'else', so you
could reduce many 'tab' and reduce the probability of one line over 80
character.

> +   buf = (u32 *)nvmem_cell_read(cell, );
> +   nvmem_cell_put(cell);
> +
> +   if (IS_ERR(buf)) {
> +   dev_info(mipi_tx->dev, "can't get data, ignore it\n");
> +   } else {

Ditto.

Regards,
Chun-Kuang.

> +   if (len < 3 * sizeof(u32)) {
> +   dev_info(mipi_tx->dev, "invalid calibration 
> data\n");
> +   kfree(buf);
> +   return;
> +   }
> +
> +   mipi_tx->rt_code[0] = ((buf[0] >> 6 & 0x1f) << 5) |
> +  (buf[0] >> 11 & 0x1f);
> +   mipi_tx->rt_code[1] = ((buf[1] >> 27 & 0x1f) << 5) |
> +  (buf[0] >> 1 & 0x1f);
> +   mipi_tx->rt_code[2] = ((buf[1] >> 17 & 0x1f) << 5) |
> +  (buf[1] >> 22 & 0x1f);
> +   mipi_tx->rt_code[3] = ((buf[1] >> 7 & 0x1f) << 5) |
> +  (buf[1] >> 12 & 0x1f);
> +   mipi_tx->rt_code[4] = ((buf[2] >> 27 & 0x1f) << 5) |
> +  (buf[1] >> 2 & 0x1f);
> +   kfree(buf);
> +   }
> +   }
> +}
> +
>  static int mtk_mipi_tx_probe(struct platform_device *pdev)
>  {
> struct device *dev = >dev;
> @@ -174,6 +212,8 @@ static int mtk_mipi_tx_probe(struct platform_device *pdev)
>
> mipi_tx->dev = dev;
>
> +   mtk_mipi_tx_get_calibration_datal(mipi_tx);
> +
> return of_clk_add_provider(dev->of_node, of_clk_src_simple_get,
>mipi_tx->pll);
>  }
> diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h 
> b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> index eea44327fe9f..c76f07c3fdeb 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> +++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> @@ -12,9 +12,11 @@
>  #include 
>  #include 
>  #include 
> +#include 
>  #include 
>  #include 
>  #include 
> +#include 
>
>  struct mtk_mipitx_data {
> const u32 mppll_preserve;
> @@ -28,6 +30,7 @@ struct mtk_mipi_tx {
> void __iomem *regs;
> u32 data_rate;
> u32 mipitx_drive;
> +   u32 rt_code[5];
> 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 e4cc967750cb..9f3e55aeebb2 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> +++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> @@ -28,6 +28,7 @@
>  #define MIPITX_PLL_CON40x003c
>  #define RG_DSI_PLL_IBIAS   (3 << 10)
>
> +#define MIPITX_D2P_RTCODE  0x0100
>  #define MIPITX_D2_SW_CTL_EN0x0144
>  #define MIPITX_D0_SW_CTL_EN0x0244
>  #define MIPITX_CK_CKMODE_EN0x0328
> @@ -108,6 +109,24 @@ static const struct clk_ops mtk_mipi_tx_pll_ops = {
> .recalc_rate = mtk_mipi_tx_pll_recalc_rate,
>  };
>
> +static void mtk_mipi_tx_config_calibration_data(struct mtk_mipi_tx *mipi_tx)
> +{
> +   int i, j;
> +
> +   for (i = 0; i < 5; i++) {
> +   if ((mipi_tx->rt_code[i] & 0x1f) == 0)
> +   mipi_tx->rt_code[i] |= 0x10;
> +
> +   if ((mipi_tx->rt_code[i] >> 5 & 0x1f) == 0)
> +   mipi_tx->rt_code[i] |= 0x10 << 5;
> +
> +  

[PATCH v5 4/4] drm/mediatek: config mipitx impedance with calibration data

2020-04-09 Thread Jitao Shi
Read calibration data from nvmem, and config mipitx impedance with
calibration data to make sure their impedance are 100ohm.

Signed-off-by: Jitao Shi 
---
 drivers/gpu/drm/mediatek/mtk_mipi_tx.c| 40 +++
 drivers/gpu/drm/mediatek/mtk_mipi_tx.h|  3 ++
 drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 21 ++
 3 files changed, 64 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c 
b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
index e301af64809e..5e91fc2c1318 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
@@ -88,6 +88,44 @@ static const struct phy_ops mtk_mipi_tx_ops = {
.owner = THIS_MODULE,
 };
 
+static void mtk_mipi_tx_get_calibration_datal(struct mtk_mipi_tx *mipi_tx)
+{
+   struct nvmem_cell *cell;
+   size_t len;
+   u32 *buf;
+
+   memset(mipi_tx->rt_code, 0, sizeof(mipi_tx->rt_code));
+   cell = nvmem_cell_get(mipi_tx->dev, "calibration-data");
+   if (IS_ERR(cell)) {
+   dev_info(mipi_tx->dev, "can't get nvmem_cell_get, ignore it\n");
+   } else {
+   buf = (u32 *)nvmem_cell_read(cell, );
+   nvmem_cell_put(cell);
+
+   if (IS_ERR(buf)) {
+   dev_info(mipi_tx->dev, "can't get data, ignore it\n");
+   } else {
+   if (len < 3 * sizeof(u32)) {
+   dev_info(mipi_tx->dev, "invalid calibration 
data\n");
+   kfree(buf);
+   return;
+   }
+
+   mipi_tx->rt_code[0] = ((buf[0] >> 6 & 0x1f) << 5) |
+  (buf[0] >> 11 & 0x1f);
+   mipi_tx->rt_code[1] = ((buf[1] >> 27 & 0x1f) << 5) |
+  (buf[0] >> 1 & 0x1f);
+   mipi_tx->rt_code[2] = ((buf[1] >> 17 & 0x1f) << 5) |
+  (buf[1] >> 22 & 0x1f);
+   mipi_tx->rt_code[3] = ((buf[1] >> 7 & 0x1f) << 5) |
+  (buf[1] >> 12 & 0x1f);
+   mipi_tx->rt_code[4] = ((buf[2] >> 27 & 0x1f) << 5) |
+  (buf[1] >> 2 & 0x1f);
+   kfree(buf);
+   }
+   }
+}
+
 static int mtk_mipi_tx_probe(struct platform_device *pdev)
 {
struct device *dev = >dev;
@@ -174,6 +212,8 @@ static int mtk_mipi_tx_probe(struct platform_device *pdev)
 
mipi_tx->dev = dev;
 
+   mtk_mipi_tx_get_calibration_datal(mipi_tx);
+
return of_clk_add_provider(dev->of_node, of_clk_src_simple_get,
   mipi_tx->pll);
 }
diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h 
b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
index eea44327fe9f..c76f07c3fdeb 100644
--- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
+++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
@@ -12,9 +12,11 @@
 #include 
 #include 
 #include 
+#include 
 #include 
 #include 
 #include 
+#include 
 
 struct mtk_mipitx_data {
const u32 mppll_preserve;
@@ -28,6 +30,7 @@ struct mtk_mipi_tx {
void __iomem *regs;
u32 data_rate;
u32 mipitx_drive;
+   u32 rt_code[5];
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 e4cc967750cb..9f3e55aeebb2 100644
--- a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
+++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
@@ -28,6 +28,7 @@
 #define MIPITX_PLL_CON40x003c
 #define RG_DSI_PLL_IBIAS   (3 << 10)
 
+#define MIPITX_D2P_RTCODE  0x0100
 #define MIPITX_D2_SW_CTL_EN0x0144
 #define MIPITX_D0_SW_CTL_EN0x0244
 #define MIPITX_CK_CKMODE_EN0x0328
@@ -108,6 +109,24 @@ static const struct clk_ops mtk_mipi_tx_pll_ops = {
.recalc_rate = mtk_mipi_tx_pll_recalc_rate,
 };
 
+static void mtk_mipi_tx_config_calibration_data(struct mtk_mipi_tx *mipi_tx)
+{
+   int i, j;
+
+   for (i = 0; i < 5; i++) {
+   if ((mipi_tx->rt_code[i] & 0x1f) == 0)
+   mipi_tx->rt_code[i] |= 0x10;
+
+   if ((mipi_tx->rt_code[i] >> 5 & 0x1f) == 0)
+   mipi_tx->rt_code[i] |= 0x10 << 5;
+
+   for (j = 0; j < 10; j++)
+   mtk_mipi_tx_update_bits(mipi_tx,
+   MIPITX_D2P_RTCODE * (i + 1) + j * 4,
+   1, mipi_tx->rt_code[i] >> j & 1);
+   }
+}
+
 static void mtk_mipi_tx_power_on_signal(struct phy *phy)
 {
struct mtk_mipi_tx *mipi_tx = phy_get_drvdata(phy);
@@ -130,6 +149,8 @@ static void mtk_mipi_tx_power_on_signal(struct phy *phy)
RG_DSI_HSTX_LDO_REF_SEL,