Re: [PATCH v1 2/2] drm/mediatek: add mipi_tx driver for mt8183

CK Hu
2019-02-20T08:34:18Z

Hi, Jitao:

On Tue, 2019-02-19 at 17:14 +0800, Jitao Shi wrote:
> This patch add mt8183 mipi_tx driver.
> And also support other chips that use the same binding and driver.
>
> Signed-off-by: Jitao Shi <jitao.shi@mediatek.com>
> ---
> drivers/gpu/drm/mediatek/mtk_mipi_tx.c | 2 +
> drivers/gpu/drm/mediatek/mtk_mipi_tx.h | 1 +
> drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c | 168 ++++++++++++++++++
> 3 files changed, 171 insertions(+)
> create mode 100644 drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
> index fa361c8be8d7..83fb7717d383 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
> +++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.c
> @@ -198,6 +198,8 @@ static const struct of_device_id mtk_mipi_tx_match[] = {
> .data = &mt2701_mipitx_data },
> { .compatible = "mediatek,mt8173-mipi-tx",
> .data = &mt8173_mipitx_data },
> + { .compatible = "mediatek,mt8183-mipi-tx",

This compatible string does not exist in [1], please add it.

[1]
https://www.kernel.org/doc/Documentation/devicetree/bindings/display/mediatek/mediatek%2Cdsi.txt

> + .data = &mt8183_mipitx_data },
> { },
> };
>
> diff --git a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> index 2d7f05b0d6a7..af83023e81cf 100644
> --- a/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> +++ b/drivers/gpu/drm/mediatek/mtk_mipi_tx.h
> @@ -47,5 +47,6 @@ unsigned long mtk_mipi_tx_pll_recalc_rate(struct clk_hw *hw,
>
> extern const struct mtk_mipitx_data mt2701_mipitx_data;
> extern const struct mtk_mipitx_data mt8173_mipitx_data;
> +extern const struct mtk_mipitx_data mt8183_mipitx_data;
>
> #endif
> diff --git a/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> new file mode 100644
> index 000000000000..07f70a3cad13
> --- /dev/null
> +++ b/drivers/gpu/drm/mediatek/mtk_mt8183_mipi_tx.c
> @@ -0,0 +1,168 @@
> +/*
> + * Copyright (c) 2015 MediaTek Inc.

2019

> + *
> + * This program is free software; you can redistribute it and/or modify
> + * it under the terms of the GNU General Public License version 2 as
> + * published by the Free Software Foundation.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */

Please follow the license rule [1].

[1] https://www.kernel.org/doc/html/v4.20/process/license-rules.html

> +
> +#include "mtk_mipi_tx.h"
> +
> +#define MIPITX_LANE_CON 0x000c
> +#define RG_DSI_CPHY_T1DRV_EN BIT(0)
> +#define RG_DSI_ANA_CK_SEL BIT(1)
> +#define RG_DSI_PHY_CK_SEL BIT(2)
> +#define RG_DSI_CPHY_EN BIT(3)
> +#define RG_DSI_PHYCK_INV_EN BIT(4)
> +#define RG_DSI_PWR04_EN BIT(5)
> +#define RG_DSI_BG_LPF_EN BIT(6)
> +#define RG_DSI_BG_CORE_EN BIT(7)
> +#define RG_DSI_PAD_TIEL_SEL BIT(8)

Aligned to mt8173_mipi_tx.c, bitwise definition would add one more
'tab'.

> +
> +#define MIPITX_PLL_PWR 0x0028
> +#define MIPITX_PLL_CON0 0x002c
> +#define MIPITX_PLL_CON1 0x0030
> +#define MIPITX_PLL_CON2 0x0034
> +#define MIPITX_PLL_CON3 0x0038
> +#define MIPITX_PLL_CON4 0x003c
> +#define RG_DSI_PLL_IBIAS (3 << 10)
> +
> +#define MIPITX_D2_SW_CTL_EN 0x0144
> +#define MIPITX_D0_SW_CTL_EN 0x0244
> +#define MIPITX_CK_CKMODE_EN 0x0328
> +#define DSI_CK_CKMODE_EN BIT(0)
> +#define MIPITX_CK_SW_CTL_EN 0x0344
> +#define MIPITX_D1_SW_CTL_EN 0x0444
> +#define MIPITX_D3_SW_CTL_EN 0x0544
> +#define DSI_SW_CTL_EN BIT(0)
> +#define AD_DSI_PLL_SDM_PWR_ON BIT(0)
> +#define AD_DSI_PLL_SDM_ISO_EN BIT(1)
> +
> +#define RG_DSI_PLL_EN BIT(4)
> +#define RG_DSI_PLL_POSDIV (0x7 << 8)
> +
> +static int mtk_mipi_tx_pll_prepare(struct clk_hw *hw)
> +{
> + struct mtk_mipi_tx *mipi_tx = mtk_mipi_tx_from_clk_hw(hw);
> + unsigned int txdiv, txdiv0, txdiv1;

txdiv1 is useless, so remove it.

> + u64 pcw;
> + int ret;
> +
> + dev_dbg(mipi_tx->dev, "prepare: %u bps\n", mipi_tx->data_rate);
> +
> + if (mipi_tx->data_rate >= 2000000000) {
> + txdiv = 1;
> + txdiv0 = 0;
> + txdiv1 = 0;
> + } else if (mipi_tx->data_rate >= 1000000000) {
> + txdiv = 2;
> + txdiv0 = 1;
> + txdiv1 = 0;
> + } else if (mipi_tx->data_rate >= 500000000) {
> + txdiv = 4;
> + txdiv0 = 2;
> + txdiv1 = 0;
> + } else if (mipi_tx->data_rate > 250000000) {
> + txdiv = 8;
> + txdiv0 = 3;
> + txdiv1 = 0;
> + } else if (mipi_tx->data_rate >= 125000000) {
> + txdiv = 16;
> + txdiv0 = 4;
> + txdiv1 = 0;
> + } else {
> + return -EINVAL;
> + }
> +
> + ret = clk_prepare_enable(mipi_tx->ref_clk);
> + if (ret < 0) {
> + dev_err(mipi_tx->dev, "can't mipi_tx ref_clk %d\n", ret);

"can't prepare and enable mipi_tx ref_clk...

> + return ret;
> + }
> +
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_PLL_CON4, RG_DSI_PLL_IBIAS);
> +
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_PLL_PWR, AD_DSI_PLL_SDM_PWR_ON);
> + usleep_range(30, 100);
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_PLL_PWR, AD_DSI_PLL_SDM_ISO_EN);
> + pcw = div_u64(((u64)mipi_tx->data_rate * txdiv) << 24, 26000000);
> + writel(pcw, mipi_tx->regs + MIPITX_PLL_CON0);
> + mtk_mipi_tx_update_bits(mipi_tx, MIPITX_PLL_CON1, RG_DSI_PLL_POSDIV,
> + txdiv0 << 8);
> + usleep_range(1000, 2000);
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_PLL_CON1, RG_DSI_PLL_EN);
> +
> + return 0;
> +}
> +
> +static void mtk_mipi_tx_pll_unprepare(struct clk_hw *hw)
> +{
> + struct mtk_mipi_tx *mipi_tx = mtk_mipi_tx_from_clk_hw(hw);
> +
> + dev_dbg(mipi_tx->dev, "unprepare\n");
> +
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_PLL_CON1, RG_DSI_PLL_EN);
> + /* step 1: SDM_RWR_ON / SDM_ISO_EN */

This comment to the code before it or after it?

> +
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_PLL_PWR, AD_DSI_PLL_SDM_ISO_EN);
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_PLL_PWR, AD_DSI_PLL_SDM_PWR_ON);
> + clk_disable_unprepare(mipi_tx->ref_clk);
> +}
> +
> +static const struct clk_ops mtk_mipi_tx_pll_ops = {
> + .prepare = mtk_mipi_tx_pll_prepare,
> + .unprepare = mtk_mipi_tx_pll_unprepare,
> + .round_rate = mtk_mipi_tx_pll_round_rate,
> + .set_rate = mtk_mipi_tx_pll_set_rate,
> + .recalc_rate = mtk_mipi_tx_pll_recalc_rate,
> +};
> +
> +static void mtk_mipi_tx_power_on_signal(struct phy *phy)
> +{
> + struct mtk_mipi_tx *mipi_tx = phy_get_drvdata(phy);
> +
> + /* BG_LPF_EN / BG_CORE_EN */
> + writel(RG_DSI_PAD_TIEL_SEL | RG_DSI_BG_CORE_EN,
> + mipi_tx->regs + MIPITX_LANE_CON);
> + usleep_range(30, 100);
> + writel(RG_DSI_BG_CORE_EN | RG_DSI_BG_LPF_EN,
> + mipi_tx->regs + MIPITX_LANE_CON);
> +
> + /* Switch OFF each Lane */
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_D0_SW_CTL_EN, DSI_SW_CTL_EN);
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_D1_SW_CTL_EN, DSI_SW_CTL_EN);
> + mtk_mipi_tx_clear_bits(mipi_tx, MIPITX_D2_SW_CTL_EN, DSI_SW_CTL_EN);
> + 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_set_bits(mipi_tx, MIPITX_CK_CKMODE_EN, DSI_CK_CKMODE_EN);
> +}
> +
> +static void mtk_mipi_tx_power_off_signal(struct phy *phy)
> +{
> + struct mtk_mipi_tx *mipi_tx = phy_get_drvdata(phy);
> +
> + /* Switch ON each Lane */
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_D0_SW_CTL_EN, DSI_SW_CTL_EN);
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_D1_SW_CTL_EN, DSI_SW_CTL_EN);
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_D2_SW_CTL_EN, DSI_SW_CTL_EN);
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_D3_SW_CTL_EN, DSI_SW_CTL_EN);
> + mtk_mipi_tx_set_bits(mipi_tx, MIPITX_CK_SW_CTL_EN, DSI_SW_CTL_EN);
> +
> + /* step 2 */

I would like the comment to give some information, but this comment does
not show any information. Make it more meaningful, otherwise, remove it.

> + writel(RG_DSI_PAD_TIEL_SEL | RG_DSI_BG_CORE_EN,
> + mipi_tx->regs + MIPITX_LANE_CON);
> + writel(RG_DSI_PAD_TIEL_SEL, mipi_tx->regs + MIPITX_LANE_CON);
> +}
> +
> +const struct mtk_mipitx_data mt8183_mipitx_data = {
> + .mipi_tx_clk_ops = &mtk_mipi_tx_pll_ops,
> + .mipi_tx_enable_signal = mtk_mipi_tx_power_on_signal,
> + .mipi_tx_disable_signal = mtk_mipi_tx_power_off_signal,
> +};
> +

Remove the latest blank line.

Regards,
CK