On 02-04-22, 13:24, Liu Ying wrote:
> i.MX8qxp SoC embeds a Mixel MIPI DPHY + LVDS PHY combo which supports
> either a MIPI DSI display or a LVDS display.  The PHY mode is controlled
> by SCU firmware and the driver would call a SCU firmware function to
> configure the PHY mode.  The single LVDS PHY has 4 data lanes to support
> a LVDS display.  Also, with a master LVDS PHY and a slave LVDS PHY, they
> may work together to support a LVDS display with 8 data lanes(usually, dual
> LVDS link display).  Note that this patch supports the LVDS PHY mode only
> for the i.MX8qxp Mixel combo PHY, i.e., the MIPI DPHY mode is yet to be
> supported, so for now error would be returned from ->set_mode() if MIPI
> DPHY mode is passed over to it for the combo PHY.
> 
> Cc: Guido Günther <a...@sigxcpu.org>
> Cc: Robert Chiras <robert.chi...@nxp.com>
> Cc: Kishon Vijay Abraham I <kis...@ti.com>
> Cc: Vinod Koul <vk...@kernel.org>
> Cc: Shawn Guo <shawn...@kernel.org>
> Cc: Sascha Hauer <s.ha...@pengutronix.de>
> Cc: Pengutronix Kernel Team <ker...@pengutronix.de>
> Cc: Fabio Estevam <feste...@gmail.com>
> Cc: NXP Linux Team <linux-...@nxp.com>
> Reviewed-by: Guido Günther <a...@sigxcpu.org>
> Signed-off-by: Liu Ying <victor....@nxp.com>
> ---
> v5->v6:
> * No change.
> 
> v4->v5:
> * No change.
> 
> v3->v4:
> * Add Guido's R-b tag.
> 
> v2->v3:
> * Improve readability of mixel_dphy_set_mode(). (Guido)
> 
> v1->v2:
> * Print invalid PHY mode in dmesg. (Guido)
> 
>  .../phy/freescale/phy-fsl-imx8-mipi-dphy.c    | 269 +++++++++++++++++-
>  1 file changed, 258 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c 
> b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> index a95572b397ca..af1ecda091c7 100644
> --- a/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> +++ b/drivers/phy/freescale/phy-fsl-imx8-mipi-dphy.c
> @@ -4,17 +4,31 @@
>   * Copyright 2019 Purism SPC
>   */
>  
> +#include <linux/bitfield.h>
>  #include <linux/clk.h>
>  #include <linux/clk-provider.h>
>  #include <linux/delay.h>
> +#include <linux/firmware/imx/ipc.h>
> +#include <linux/firmware/imx/svc/misc.h>
>  #include <linux/io.h>
>  #include <linux/kernel.h>
> +#include <linux/mfd/syscon.h>
>  #include <linux/module.h>
>  #include <linux/of.h>
>  #include <linux/of_platform.h>
>  #include <linux/phy/phy.h>
>  #include <linux/platform_device.h>
>  #include <linux/regmap.h>
> +#include <dt-bindings/firmware/imx/rsrc.h>
> +
> +/* Control and Status Registers(CSR) */
> +#define PHY_CTRL                     0x00
> +#define  CCM_MASK                    GENMASK(7, 5)
> +#define  CCM(n)                              FIELD_PREP(CCM_MASK, (n))
> +#define  CA_MASK                     GENMASK(4, 2)
> +#define  CA(n)                               FIELD_PREP(CA_MASK, (n))
> +#define  RFB                         BIT(1)
> +#define  LVDS_EN                     BIT(0)
>  
>  /* DPHY registers */
>  #define DPHY_PD_DPHY                 0x00
> @@ -55,8 +69,15 @@
>  #define PWR_ON       0
>  #define PWR_OFF      1
>  
> +#define MIN_VCO_FREQ 640000000
> +#define MAX_VCO_FREQ 1500000000
> +
> +#define MIN_LVDS_REFCLK_FREQ 24000000
> +#define MAX_LVDS_REFCLK_FREQ 150000000
> +
>  enum mixel_dphy_devtype {
>       MIXEL_IMX8MQ,
> +     MIXEL_IMX8QXP,
>  };
>  
>  struct mixel_dphy_devdata {
> @@ -65,6 +86,7 @@ struct mixel_dphy_devdata {
>       u8 reg_rxlprp;
>       u8 reg_rxcdrp;
>       u8 reg_rxhs_settle;
> +     bool is_combo;  /* MIPI DPHY and LVDS PHY combo */
>  };
>  
>  static const struct mixel_dphy_devdata mixel_dphy_devdata[] = {
> @@ -74,6 +96,10 @@ static const struct mixel_dphy_devdata 
> mixel_dphy_devdata[] = {
>               .reg_rxlprp = 0x40,
>               .reg_rxcdrp = 0x44,
>               .reg_rxhs_settle = 0x48,
> +             .is_combo = false,
> +     },
> +     [MIXEL_IMX8QXP] = {
> +             .is_combo = true,
>       },
>  };
>  
> @@ -95,8 +121,12 @@ struct mixel_dphy_cfg {
>  struct mixel_dphy_priv {
>       struct mixel_dphy_cfg cfg;
>       struct regmap *regmap;
> +     struct regmap *lvds_regmap;
>       struct clk *phy_ref_clk;
>       const struct mixel_dphy_devdata *devdata;
> +     struct imx_sc_ipc *ipc_handle;
> +     bool is_slave;
> +     int id;
>  };
>  
>  static const struct regmap_config mixel_dphy_regmap_config = {
> @@ -317,7 +347,8 @@ static int mixel_dphy_set_pll_params(struct phy *phy)
>       return 0;
>  }
>  
> -static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts 
> *opts)
> +static int
> +mixel_dphy_configure_mipi_dphy(struct phy *phy, union phy_configure_opts 
> *opts)

Please dont change things like this.. A patch should do only one thing :)

>  {
>       struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
>       struct mixel_dphy_cfg cfg = { 0 };
> @@ -345,15 +376,121 @@ static int mixel_dphy_configure(struct phy *phy, union 
> phy_configure_opts *opts)
>       return 0;
>  }
>  
> +static int
> +mixel_dphy_configure_lvds_phy(struct phy *phy, union phy_configure_opts 
> *opts)
> +{
> +     struct mixel_dphy_priv *priv = phy_get_drvdata(phy);
> +     struct phy_configure_opts_lvds *lvds_opts = &opts->lvds;
> +     unsigned long data_rate;
> +     unsigned long fvco;
> +     u32 rsc;
> +     u32 co;
> +     int ret;
> +
> +     priv->is_slave = lvds_opts->is_slave;

I think you should check if lvds_opts is valid before dereferencing it..

> +
> +     /* LVDS interface pins */
> +     regmap_write(priv->lvds_regmap, PHY_CTRL, CCM(0x5) | CA(0x4) | RFB);

can we avoid magic numbers?

> +
> +     /* enable MODE8 only for slave LVDS PHY */
> +     rsc = priv->id ? IMX_SC_R_MIPI_1 : IMX_SC_R_MIPI_0;
> +     ret = imx_sc_misc_set_control(priv->ipc_handle, rsc, IMX_SC_C_DUAL_MODE,
> +                                   lvds_opts->is_slave);
> +     if (ret) {
> +             dev_err(&phy->dev, "Failed to configure MODE8: %d\n", ret);
> +             return ret;
> +     }
> +
> +     /*
> +      * Choose an appropriate divider ratio to meet the requirement of
> +      * PLL VCO frequency range.
> +      *
> +      *  -----  640MHz ~ 1500MHz   ------------      ---------------
> +      * | VCO | ----------------> | CO divider | -> | LVDS data rate|
> +      *  -----       FVCO          ------------      ---------------
> +      *                            1/2/4/8 div     7 * differential_clk_rate
> +      */
> +     data_rate = 7 * lvds_opts->differential_clk_rate;
> +     for (co = 1; co <= 8; co *= 2) {
> +             fvco = data_rate * co;
> +
> +             if (fvco >= MIN_VCO_FREQ)
> +                     break;
> +     }
> +
> +     if (fvco < MIN_VCO_FREQ || fvco > MAX_VCO_FREQ) {
> +             dev_err(&phy->dev, "VCO frequency %lu is out of range\n", fvco);
> +             return -ERANGE;
> +     }
> +
> +     /*
> +      * CO is configurable, while CN and CM are not,
> +      * as fixed ratios 1 and 7 are applied respectively.
> +      */
> +     phy_write(phy, __ffs(co), DPHY_CO);
> +
> +     /* set reference clock rate */
> +     clk_set_rate(priv->phy_ref_clk, lvds_opts->differential_clk_rate);
> +
> +     return ret;
> +}
> +
> +static int mixel_dphy_configure(struct phy *phy, union phy_configure_opts 
> *opts)
> +{
> +     if (phy->attrs.mode == PHY_MODE_MIPI_DPHY)
> +             return mixel_dphy_configure_mipi_dphy(phy, opts);
> +     else if (phy->attrs.mode == PHY_MODE_LVDS)
> +             return mixel_dphy_configure_lvds_phy(phy, opts);
> +
> +     dev_err(&phy->dev,
> +             "Failed to configure PHY with invalid PHY mode: %d\n",
> +                                                     phy->attrs.mode);

single line for this please

> +     return -EINVAL;
> +}
> +
> +static int
> +mixel_dphy_validate_lvds_phy(struct phy *phy, union phy_configure_opts *opts)
> +{
> +     struct phy_configure_opts_lvds *lvds_cfg = &opts->lvds;
> +
> +     if (lvds_cfg->bits_per_lane_and_dclk_cycle != 7) {
> +             dev_err(&phy->dev, "Invalid bits per LVDS data lane: %u\n",
> +                                     lvds_cfg->bits_per_lane_and_dclk_cycle);
> +             return -EINVAL;
> +     }
> +
> +     if (lvds_cfg->lanes != 4) {
> +             dev_err(&phy->dev, "Invalid LVDS data lanes: %u\n",
> +                                             lvds_cfg->lanes);

here too, make it better read

> +             return -EINVAL;
> +     }
> +
> +     if (lvds_cfg->differential_clk_rate < MIN_LVDS_REFCLK_FREQ ||
> +         lvds_cfg->differential_clk_rate > MAX_LVDS_REFCLK_FREQ) {
> +             dev_err(&phy->dev,
> +                     "Invalid LVDS differential clock rate: %lu\n",
> +                                     lvds_cfg->differential_clk_rate);
> +             return -EINVAL;
> +     }
> +
> +     return 0;
> +}
> +
>  static int mixel_dphy_validate(struct phy *phy, enum phy_mode mode, int 
> submode,
>                              union phy_configure_opts *opts)
>  {
> -     struct mixel_dphy_cfg cfg = { 0 };
> +     if (mode == PHY_MODE_MIPI_DPHY) {
> +             struct mixel_dphy_cfg mipi_dphy_cfg = { 0 };
>  
> -     if (mode != PHY_MODE_MIPI_DPHY)
> -             return -EINVAL;
> +             return mixel_dphy_config_from_opts(phy, &opts->mipi_dphy,
> +                                                     &mipi_dphy_cfg);

the line should be justified to previos line open brace (checkpatch
--strict will warn you about this style miss)

-- 
~Vinod

Reply via email to